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اثـر التدريس بالمنظمات التخطيطية وبابعاد التــعلم في تحصيل مادة علم الاحياء وعادات العقل عند طلاب الصف الرابع العلمي == The Effect of teaching by Graph Organizers and Dimensional learning in the Achievement of Biology and Habits of mind among Fourth Class Science Student male

اسم المؤلف: قصي قاسم جايد فليح الركابي
اسم المشرف: نادية حسين يونس | اسماعيل ابراهيم علي
الموضوع العام: العلوم التربوية
السنة: 2015
الموضوع الدقيق: طرائق تدريس علوم الحياة
الدرجة: دكتوراه
الجامعة: جامعة بغداد
اللغة: العربية
مكان الجامعة: بغداد
الصفحات الاولى:

دراسة بعض المعالم المناعية لمرضى التصلب المتعدد العراقيين == Study of Some Immunological Parameters in Iraqi Patients with Multiple Scler

اسم المؤلف: هند قصي اسماعیل الفرضي
اسم المشرف: حازمة موسى خلیل العباسي
الموضوع العام: علوم الحياة
السنة: 2015
الموضوع الدقيق: الحيوان - المناعة
الدرجة: ماجستير
الجامعة: جامعة بغداد
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: Multiple sclerosis (MS) is an inflammatory condition that affects central nervous system (CNS) causing neurological dysfunction. The current study aim was the evaluation of the role of Methylprednisolone (MP), Interferon Beta (IFN - β) as disease treatments, and to investigate their influence on CD25+ FoxP3 T regulatory cells (it was counted by flow cytometry technique), IL - 8, IL - 17 (pro - inflammatory cytokines), IL - 12 (inflammatory cytokine (T cells differentiation Factor)), IL - 10, TGF - β (anti - Inflammatory cytokines) it estimated by ELISA technique, also the total and differential WBC count, ESR, CRP (inflammatory indicators), patient characteristics, clinical manifestation and life style characteristics. Forty - five Iraqi MS patients (15 untreated as early onset patients, 15 MP treated patients and 15 IFN - β treated patients), in addition to 15 apparently healthy individuals as control. For patients treated with MP, samples collected after treatment period, while patients treated with IFN - β samples were collected in remission status.The study revealed the following results : 1. Patient general characteristics showed that according to gender distribution female : male ratio was 2 : 1 (66.67% : 33.33%), according to the age of onset, (< 30 years) group of patients were the highest frequency in study sample (37.9%), 57 years was the maximum age of onset and 13 years was the minimum, with mean (34.93), Baghdad was the highest governorate in MS onset (73.33%). 2. Total WBC count showed that patients treated with MP (10.38*103μl) increases significantly (P≤0.002), (P≤0.001) as compared with both patients treated with IFN - β (7.45*103μl) and control (7.33*103μl) respectively. Lymphocytes were decrease significantly (P≤0.013), (P≤0.030) patients treated with MP and INF - β respectively (1.82), (1.92) as compared to control (2.58) and there were a significant decrease (P≤0.03) in patients treated with MP (1.82*103μl) as compared to untreated patients (2.47*103μl).Neutrophils was increase significantly (P≤0.016) and (P≤0.000) in patients treated with MP and untreated patients respectively (7.81), (5.99) as compared to control (3.82), there were also a significant increase in patients treated with MP (P≤0.04), (P≤0.001) ascompared with untreated patients (5.99*103μl) and patients treated with IFN - β (4.73*103μl) respectively. Basophils decrease significantly (P≤0.001), (P≤0.014) in both patients treated with MP and INF - β respectively (0.05), (0.06) as compared to control (0.08).3. CD25+ FoxP3+ Tregs counting showed a significant increase (P≤0.002) in untreated patients (28.01%) as compared to control 14.06%), while there were a significant decrease (P≤0.016), (P≤0.007) in both patients treated with MP and IFN - β respectively(3.70%), (2.44%) as compared to control, also there were a significant increase (P≤0.000), (P≤0.000) in untreated patients (28.01%) as compared with patients treated with MP (3.70%) and patients treated with IFN - β (2.44%) respectively.4. Serum cytokines estimation showed that IL - 8 decreased significantly (P≤0.026) in untreated patients (0.003pg/ml) as compared to control (0.016), while IL - 10, IL - 12, IL - 17 showed no significances and TGF - β increased significantly (P≤0.028) inpatients treated with MP (700.27) as compared to control (392.13), while there were a significant increasing (P≤0.001), (P≤0.001) in patients treated with MP (700.27pg/ml) as compared with untreated patients (235pg/ml) and patients treated with IFN - β (484.67pg/ml) respectively. Saliva cytokines estimation showed that IL - 8 was increased significantly (P≤0.023) in patients treated with IFN - β (0.578) as compared to control (0.223), IL - 10 increased significantly (P≤0.017) in patients treated with MP (0.023) as compared to control(0.00), IL - 12 decreased significantly (P≤0.003) in patients treated with IFN - β (4.93) as compared to control (24.07), IL - 17 increased significantly (P≤0.018) in patients treated with MP (19.17) as compared to control (0.00).

الممرضات الداخلية المسببة لحالات الاسهال لدى الاعمار من 1 - 15 سنة في مدينة بغداد

اسم المؤلف: مروة محمد نصري التميمي
اسم المشرف: سلوى صبر محسن
الموضوع العام: علوم الحياة
السنة: 2015
الدرجة: ماجستير
الجامعة: جامعة بغداد
اللغة: العربية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: The diarrhea is Enteropathy characterized liquidity abnormal,because of the increases by the movement of colon in the general way, may be represent a good sign to the Enteropathy like the Entamoeba histolytica disease, viruses Enteropathogen and bacteria,The diarrhea and associated of droughts state remains the major problem to the job of medial health in the medial east especially in the age under 5 years old.This study design to study the reason of the diarrhea and diagnosis and the effect result of it in the children under 15 years old, theirs patient from (learn hospital of alemamenalkadoman) in the city of Baghdad from 25/4/2014 to 1/10/2014 period of time, the study represent 103 sample of Stool and blood from children between (>1 - 15)years wasSufferers from diarrhea state, this state diagnose with infection of parasite (E.histolytica, G.lamblia, and others), Rotaviruses and bacteria E.coli.It use the general stool examination direct (by eyes) and in direct (by microscope) to diagnose the antigen of rotaviruses in stool, Either the blood sample store in two tube one of it contain EDTA use to CBC, Pcv, Hb, w.b.c, ABO group measure, and the second one is empty from the EDTA use to ayanlsys serum to measure (CRP) and Interleukin in the patient diarrhea.From summation of 103 found that 50 (48.54%) infected by intestinal protozoa, 41 (39.80%) infected by Rotaviruses, 9 (8.73%) infected by mixed (Parasite + Rotavirus), 3 (2.91%) infected by bacteria E.coli.50 sample infected by intestinal protozoa (42 sample is infected with one Species of parasite and 8 sample of stool continue two type of the parasite), the highest ration of infection was E.histolytica 50%, G.lamblia 38.10%, Blastocystis hominis 7.14%, and the lowestBalantidium coli 4.76%, the study recode the highest ration of mixed infected (Parasite + Rotavirus) was between G.lamblia + Rotavirus 33.33%.In This study present we found highest deference between male and female in the infection of parasite and rotavirus, male record (62 - 60)% and female (38 - 40)% on series, mixed infected (parasite + Rotavirus) Reached to the female 55.56% and this is the highest ration infection from the male 44.44%, notice that there is high Significant difference in the ratio of infection between the Age groups of the groups studied at the probability of p<0.01, where recording rotavirus infection IIhigher ratio infection in the Age groups (1 - 5) year 66,67% and less ratio 11,11% where age groups less than year, but the parasite infection only was more age group infected liable (more than 5) year with ratio 56% and smallest ratio for age group (less than year) 18%. And in the result media use (L.E) to culture E.histolytica and discover from the study , this media don’t provide good environment to maintain the parasite and resolve it for a limited period without multiplication or increase in number is it, in the case of trophzoite stage culture it stay with out - increases in the number is for one day only and after bass 24 hour transfer to the cyst stage and remain bass 3 day only and despair in the fourth day, while in culture of cyst stage Found that Noway to transform to the trophzoite stage like it happen in the human body but stay in the case of cyst stage on states. With condition E.histolytica that the Stool samples continue blood and mucous only to contain a lot off mass from the trophzoite stage and this stage only can be increases causes increase in number.Noted that this culture never dedicated only to the cultivation E.histolytica but noted the trophzoite stage exist for parasite B.coli in this stage and when culture sample from Stool contain B.coli and remain this stage Governor of the trophozoite stage for a period of two days.Either for the blood type test has been shown by the study, the highest percentage recorded rotaviruses injury in people living with antigen type A 39.59%, 39% and 44.44% for parasitic and rotavirus infections and joint respectively.And gave a hemoglobin level of Hb and size precipitation of red blood cells PCV lowest level at co - infection (parasit + rotavirus), followed by rotaviral and parasitic infection compared with control group P <0.05. Showed parasitic infection and joint significant difference in the total number of white blood cells when the probability of P <0.05, either rotaviral infection did not give a significant difference with the control group.The results of the present study about differential count of white blood cells, showed no significant difference comparing with study groups, but showed significant difference within the three groups with control group that remain the value of the Moral difference p<0.05 When all of the (Neutrophil ،Basophile ،Eosenophil)However, it did not register significant difference when cells Lymphocyte.When statistical analysis when studying some immunological changes associated with injuries intestinal regarding the number of days that lasted the case of diarrhea, and by which they can determine if the injury was severe diarrhea or chronic, and that gave significant difference (1 - 2) day P <0.01 when (3 - 4) day and (more than 4) on the value of the differences P <0.05.log CRP level of rotavirus infections 31.70%, 0.52% for infections with parasite, 88.89% of the common injuries (parasitic + viral) gave at P <0.01 probability asignificant differences.The results of the study of some of the dynamics of cellular aggregates of the study and its relationship to the immune response. Observed statistically significant at the use of IL - 10 three of its study groups recorded a significant P <0.05 was higher at 1.22% viral infection compared to the control group. Parasitic infection and did not record any significant difference.And log IL - 17A highest percentage increase at the joint injury, and there is no significant difference between the incidence of parasitic and viral infection.For IL - 33 infection joint highest recorded percentage of injury followed by a parasitic infection and finally viral. and IL - 4 infection shared the highest rate, followed by injury viral recorded and finally parasitic and gave moral difference P <0.05 and finally INF - gama, which did not record any significant differences when comparing the groups study together but gave at P <0.01probability moral differences with group of control when compared recorded the highest common injury is also high.

تعدد الاشكال الوراثية لبعض انظمة مجاميع الدم في مرضى ابيضاض الدم النيقياني == Genetic Polymorphism of Some Blood Group Systems in Myelogenous Leukemic Patients

اسم المؤلف: رشا حسن صدام السوداني
اسم المشرف: نصر فرحان عبد الله
الموضوع العام: علوم الحياة
السنة: 2015
الدرجة: ماجستير
الجامعة: جامعة بغداد
اللغة: العربية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: Assay has been made for ABO, Rh, Lewis, MNS and Duffy blood groups in a sample consisted of 80 affected individuals with chronic myelogenous leukemia (CML) and other sample consisted of 65 individuals affected with acute myelogenous leukemia (AML). Comparison have been made between each of the Leukemia sample with the control samples which consisted of 100 Healthy individuals.The results of the various comparisons were as follows : 1 - There is insignificant difference in frequency of ABO blood group in chronic and acute leukemia as compared with the control sample.2 - There are significant differences for Rh system patterns due to diminish of CcDee and ccDEe phenotypic patterns in both chronic and acute myelogenous leukemia, Moreover, there is an increase in CCDee pattern in CML and also an increase in CcDEe pattern in AML.3 - There are significant differences (P <0.001) for Lewis group blood in CML as compared with the control samples, also there is significant difference (P <0.05) in AML due to decrease in Le (a - b +) phenotype which resistant to the disease, and an increase in Le (a - b - ) phenotype.4 - There are significant differences (P <0.001) for MN blood group in both types of the disease (CML and AML), due to an increase in M + N + phenotype and decrease in M + N - phenotype. Also there is significant difference for Ss blood group in (AML), because of the increase in S + s + phenotype and decrease in S - s+ phenotype.5 - There is significant difference for Duffy group blood in CML, since the Fy (a + b - ) phenotype was decreased and the Fy (a - b +) was increased. But there is no significant difference in (AML).6 - There is no existence of disturbance or deviation in Hardy - Weinberg equilibrium for ABO, Rh and Lewis.7 - There is disturbance in Hardy - Weinberg equilibrium apparently existing for the MN blood group in both types of Leukemia as compared with the control sample . There is an increase in frequency of (N) allele in the patients and a decrease in frequency of (M) allele. There is also deviation (P <0.001) for Ss blood group in AML since allele S was increased ,but allele s was decreased in the patients as compared with the control sample .Moreover , there is deviation from this equilibrium for Duffy group blood in the overall Leukemia sample. The higher frequency of Fy ͣ allele was found in AML, while the higher frequency of Fyb and Fy alleles were found in CML . Such deviations from Hardy - Weinberg equilibrium in hematological malignancies and not deviated in the control sample may give attention about the etiology of the disease concerned.

الوصف التشكليائي والتركيب النسجي للبنكرياس المعثكلة في الخفاش الكحلي (Kuhl, 1817) Pipistrellus kuhlii == Morphological Description and Histological Structure of the Pancreas in Al - Kuhlii Bat Pipistrellus kuhlii (Kuhl, 1817)

اسم المؤلف: خالدة محمد عليوي العوادي
اسم المشرف: بيداء حسين مطلك
الموضوع العام: علوم الحياة
السنة: 2015
الموضوع الدقيق: الحيوان - الانسجة
الدرجة: ماجستير
الجامعة: جامعة بغداد
اللغة: العربية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: The present study was designed to investigate the morphological description and histological structure of the pancreas gland in Bat Pipistrellus kuhlii.A total number of (20) ,10 male and 10 female bats were used in this study after taking out the pancreas gland it was fixed with fixative solutions their the sequent steps of preparing histological slides were done after that they were stained by using routine and special stains. These stains were represented by (Heamtoxylin - Eosin, Periodic acid Schiff, Chrom alum heamtoxylin, Modified aldehyde Fuchsin and Masson’s trichrome).The morphological study showed that the pancreas gland in Kuhli's bat is represented by a compact type of pancreatic tissue it is white to yellowish color divided into three divisions head, body and tail. The pancreatic tissue lies in the abdominal cavity near the mass of intestine at the mesentery network which is connected with the coiled region of the duodenum from one side and the extended mesenteries between the dorsal part of stomach and the ventral part of spleen from the other side. The pancreas gland has only one duct that originated from the pancreatic body which is opened in the upper part of the duodenum.The pancreas gland is surrounded by loose connective tissue it extend trabeculae that divides the gland into many lobules that differs in size and shape. The pancreatic tissue is characterized into two portions, the exocrine portion and endocrine portion, the exocrine portion is represented by a compound tubule - acinar gland which consists of a large number of acini and the ductal system, each acini represented by a serous secretory unit which consists of many pyramidal cells that surround a small lumen,the apics of narrow cells are headed towards the acinar lumen while their bases are wide and based on the basement membrane. The acinar sizes are variable some acini are large others are small. The acinr cells number range from (6 to 9) cells. The ductal system which eliminate the products of secretory units to the duodenum it is initiate with centroacinar cells, these cells are connected with intercalary ducts which connected with intralobular duct, these ducts lead to the interlobular duct, which their diameter is larger than the diameter of intralobular ducts. The inter lobular ducts eliminate their secretory contents in the main duct which opened in the upper part of the duodenum.The endocrine portion is represented by clusters of cells known as islets of Langerhans which appeared as masses of cells diffused among the exocrine portion units, they're separated from each other by a thin layer of connective tissue.The islets are randomly distributed within the pancreatic tissue, it is obvious that these islets are massively concentrated in the body part of pancreas inside the lobules and around the ducts as in the pancreas head. The study also revealed that there were difference in the diameters and numbers of the islets, the mean diameters of the islets was reached (1.86) micrometer with range (1 - 2.75) micrometer whereas the mean number of islets was (1.6) islet per millimeter with rang of (1 - 3) islet.Each islet consists of three types of cells arranged as irregular clusters, they are separated from each other with blood capillary network. They were differentiated by using routine and special stains, these cells are Alpha cells they have rounded shape with oval nucleus they lies at the peripheral part of the islet. Beta cells they’re oval shaped with spherical nucleus they lies at the center of the islet, while delta cells are irregular shaped, with pale color lies between Alpha and Beta cells they’re less in number and they may appear as single cell or as small clusters and mostly lies at the peripheral part of the islet.The islet stained with faint blue in routine stains (Heamtoxylin and Eosin), and they were stained with faint blue when using special stains (Chrome alum phloxine) while the nucleus of Alpha cells stained with dark red and the Beta cells nucleus stained blue whereas Delta cells nucleus appeared in pink to pale red color. When using modified aldehyde Fuchsin the islets stained with greenish blue, alpha cells stained with orang, beta cells were blueish green and delta cells stained with green

استعمال الهائمات النباتية ادلة احيائية لتقييم تاثير الانشطة البشرية على نوعية مياه نهر بيت زوينة محافظة ديالى == Use of Phytoplankton as Biological Indicator to Evaluate the Anthropogenic Impact on Water Quality of Beat - Zwana River - Diyala

اسم المؤلف: انتصار كريم عبد الحسن الدراجي
اسم المشرف: ابراهيم مهدي عزوز السلمان
الموضوع العام: علوم الحياة
السنة: 2015
الموضوع الدقيق: النبات - الاحياء المائية
الدرجة: ماجستير
الجامعة: جامعة بغداد
اللغة: العربية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: The current study was conducted in five selected positions variety of human activities along the agricultural project named (Beat zwana River) located in Jadedat - alshat, within the province of Diyala, for the period from October 2013 until June 2014, the study included measurement of twenty - two physiochemical factors of river water environment, as well as to study the quality and quantity of community phytoplankton, has also been applied in the study a number of environmental indexes.The range of studied properties were : 10.83 - 38.75°C and 9.17 - 28.5°C for air and water temperature, water depth (16.50 - 284.33 cm), light penetration (14.50 - 152cm) , turbidity (0.27 - 106.98) NTU, electrical conductivity, EC,(514.83 - 1027.5) μS/cm , salinity (1.15 - 4.88 part per thousand), total dissolved solids, TDS (287.83 - 861.6) mg/l and total suspended solids TSS (2 - 49.87) mg/l, pH (6.25 - 7.98), dissolved oxygen, DO (3.65 - 11.25)mg/l and Biological Oxygen Demand. BOD5 (1.07 - 4.35) mg /l, total alkalinity, TA (115.33 - 178.5 ) mg /l, total hardness, TH ( 221.83 - 338.83) mg/l, Calcium, Ca (52.08 - 101.36) mg CaCO3/l, and Magnesium ,Mg (74.62 - 177.89) mg CaCO3 /l, Nitrate NO3(1.55 - 6.55) mg /l, effective phosphate PO4 (0.02 - 4.16) mg/l, Sulfate, SO4 (131.5 - 283) mg/l ,effective Silicate (4 - 2.10) mg/l, , Chlorophyll - a, ( 0.12 - 28.02) and Phaeophytin - a, (0.85 - 25.93). mg/l, respectively.Results of the present study showed that most of the studied characteristics and private (Salinity, EC, TH, PO4, BOD5, Turbidity, TDS , Ca and Mg) were of an influential or higher rates when comparing the permissible limits environmentally overall used properties of water for irrigation or aquaculture or for human consumption, according to recommendations of WHO, FAO Organization, as well as the Iraqi specifications for the river water, which shows that human activities in the region significant effect on water and environment of project.The number of phytoplankton algae that have been diagnosed in this study reached 200 species belong to 72 genera, within nine classes of the following basic algae Bacillariophyceae, Chlorophyceae, Cyanophyceae, Euglenophyceae, Raphidophyceae, Dinophyceae, Chrysophyceae, Xanthophyceae, and Cryptophyceae. The diatoms algae formed the largest percentage, as record them 131 species belong to 28 genus, and consisting 65.5%, followed by chlorophyceae 30 species belonging to 22 genus and 15%, then Cyanophyceae,22 species, to 10 genus and 11%, followed by algae Euglenophyceae 8 species belonging to 3 genus and 4%, then Cryptophyceae 3species ,to 3 genus and 1.5%, while all of the Xanthophyceae and Dinophyceae recorded 2species belonging to 2 genus and 1%, and finally the Chrysophyceae and Raphidophyceae, found them 1 species belong to 1 genus and 0.5%. Also the results showed that the distribution and biodiversity of diagnosed phytoplankton at the level of the sites, It was found that there is different for each classes from the ranks of the algae, as recorded presence in the first site 90 species belonging to 43 genus, and at the site - 2, 50 and 35 genus, and in site - 3, 68 species and 38 genus, 66 species belonging to 38 genus in site - 4, while presence 127 species belonging to 45 genus at site - 5.The quantitative study of phytoplankton in the lower and the higher ranges at the five sites ( S1, S2, S3,S4 and S5) of the study area respectively recorded the following values, (1780 - 7246 , 300 - 8180 , 220 - 2950, 560 - 3020 and 540 - 6860 cells /ml, and rates generally each site respectively, as well as 2923.6, 2027.0, 871.1, 1344.4 and 2324.6 cells/ml. when comparing the amount of algae that have been counted, we find that the highest 2923.6 rate cells/ml scored St - 1 and less than the rate of 871.1 cells/ml record in S3.In the current study we were able to record six new genus and species after checking with (Checklist of algal flora in Iraq, 2014) and consisted of these algae to : Westella linearis G. M. Smith, Navicula goppertiama Bourrelly .1981, Oedogonium minus (Wittr.) Witrock 1875. Gonyostomum seme Geitler,Gomphoniuma capitum. Bourrelly .1981, Phcus tourus (lemm.) skvortzow 1928.Also in the current study, many ecological indices were used and represented as follows : Richens index (Marglef index (1968), Similarity index (Sorenson index - 1942), Difference index (Bray and Curtis index, 1957), Presence index depended on (Chandler, 1970) and Shannon Weaver index for diversity, To evaluate the relationship between the sites and the quantity and quality of algae studied and water quality. The highest value for richness 16.246, recorded ta S5 and the highest value of the similarity 0.849 was between S1 and S5, the highest value of the difference 0.491 recorded among of S4 and S5, the highest amount of the presence of his record genus Navicula spp from pennales diatoms, feather at the level of individuals in the sample, as recorded following him to the species N. goppertiana and N. cryptocephala 3200 and 2356 cell/ml in October and November in 2013, while the highest value of diversity 1.878, by Shannon Weaver index recorded in S4. This gives an indication of the variation in the quality of water and nutrients and a physiochemical factors that lead to growth provides supportive conditions andthe spread of some species and a specific one for some of phytoplankton during the months of the year and different locations.On the basis of diversity index values, that was between 1.03 - 1.878 as less and higher, can be considered waters of the five sites between light pollution to medium pollution, and classified all within the second water category according (Wilhm guide - 1975). And this gives a conclusion no matter what the view that the water agricultural project environment (Beat - Zwana River) may be directly affected by human activities practiced by the population as well as other environmental impacts experienced by the entire region from various external and internal factors pollutants.

طرق تكرارية موثوقة لحساب تراكيز ثنائي اوكسيد الكاربون الممتص بواسطة فينيل غلايسيدل الايثر == Reliable Iterative Methods for Calculating the Concentrations of Carbon Dioxide Absorbed into Phenyl Glycidyl Ether

اسم المؤلف: غسان حسن محمود راضي
اسم المشرف: مجيد احمد ولي
الموضوع العام: علوم الرياضيات
السنة: 2015
الموضوع الدقيق: الرياضيات
الدرجة: ماجستير
الجامعة: جامعة بغداد
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: In this thesis, two reliable iterative methods are used to calculate the concentrations of carbon dioxide CO2 and phenyl glycidyl ether PGE. The first one is the variational iteration method. It is used to get an approximate solution for a system of two coupled nonlinear ordinary differential equations which represent the concentrations of CO2 and PGE. The other method is the standard homotopy analysis method which is implemented on this system. Formerly, this system has been solved by the Adomiandecomposition method. In solving this system by Adomian’s method, the nonlinearity needs calculating the Adomian’s polynomials. On the other hand, the two methods do not require any assumptions like the calculating of the Adomian’s polynomials. In this system there are boundary conditions of Dirichlet type and the other is a mix of Neumann and Dirichlet type. Our calculations are evidenced by tables and figures for the analysis of the maximal error remainder values. The variational iteration method givesapproximate solutions with fast convergence. Comparison with the results obtained by the Adomian decomposition method shows that the numerical solutions obtained by the variational iteration method converge faster than those of Adomian's method. Also, the homotopy analysis method which is implemented on this system has a very fast convergence in giving approximate solutions. Moreover, the numerical solutions resulted from the homotopy analysis method converge faster than those of Adomian's methodwhich has been implemented previously for the same problem. The numerical results also show high rates of convergence which are obtained at the increasing of the iterations. The used software of the contained calculations in our study is Mathematica 9.

تصميم شبكات عـصبية ملائمة لحل مسائل القيم الذاتية وتطبيقاتها == Design Suitable Neural Networks to Solve Eigen Value Problems and It?s Application

اسم المؤلف: عثمان مهدي صالح
اسم المشرف: عثمان مهدي صالح
الموضوع العام: علوم الرياضيات
السنة: 2015
الموضوع الدقيق: الرياضيات التطبيقية
الدرجة: ماجستير
الجامعة: جامعة بغداد
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: الهدف من هذه الرسالة هو تصميم شبكات عصبية ملائمة ذات تغذية تقدمية كطريقة لحل مسائل القيم الذاتية للمعادلات التفاضلية الاعتيادية الشاذة وغير الشاذة ذات الشروط الحدودية. الشبكة المقترحة تتعلق بحساب القيم الذاتية والدالة الذاتية المرافقة لها والتي تمثل الحل الغير صفري لنموذج المسالة.ايضا ناقشنا عدد من خوارزميات الاداء ذات المستوى العالي المستخدمة في خوارزميات تدريب الانتشار المرتد للشبكات العصبية ذات التغذية التقدمية وعرض نتائج المقارنة الحاصلة من تطبيق MATLAB مثل ﻟﻴفنبرﻙ - ماركواردت , شبيه نيوتن, تنظيم بيزن, ومن ثم تسريع اداء الشبكات المقترحة من خلال تعديل خوارزميات التدريب هذه, حيث ان بعضها يمتلك نسبة تقارب سريعة جدا لشبكات ذات احجام معقولة.الهدف الاخر لهذه الرسالة هو تحسين خوارزمية التدريب ﻟﻴفنبرﻙ - ماركوارت من خلال الاختيار المناسب للمعامل μk والذي يضمن التقارب لخوارزمية التدريب هذه.ايضا عالجنا عدة مشاكل واجهتنا اثناء تقنية التدريب مثل : التوقف المبكر, خزن الذاكرة , التنظيم وحساب مصفوفة هيسين ومعكوسها.اخيرا تم توضيح الشبكات المقترحة من خلال حل مسائل متنوعة ومقارنتها مع حلول بطرق مختلفة اخرى لاثبات سرعة , دقة وفاعلية استخدام تقنية الشبكات في حل هذا النوع من المعادلات. | The aim of this thesis is to design suitable feed forward neural networks to present a method to solve eigenvalue problems for non - singular ordinary differential equations with boundary conditions. The suggested networks concerned with the computation of eigenvalues and associated eigenfunction which represent the nontrivial solution of the problem model. Also, we will discuss several high performance algorithms used in back propagation training of the feed forward neural networks and present comparative results obtained in MATLAB implementation such as : Levenberg - Marquardt, quasi - Newton and Bayesian regularization, update procedure, then speeding suggested networks by modification these training algorithms, many of them have a very fast convergence rate for reasonable size networks.Other aims of this thesis is to modify Levenberg - Marquardt training algorithm by suitable choice of the parameter μk which guarantee super linearly convergence for this training algorithm. Also, we treat many problems that confront during the training technique such as : early stopping, memory storage, regularization and calculating of Hessian matrix and its inverse.Finally, illustrate the suggested networks by solving a variety of model problems and present comparisons with solutions obtained using other different methods to show speed, accuracy and effectiveness of using the networks technique for solving this type of equations

المقاسات الجزيئة المقاسات المستحوذة على 2 وبعض اعماماتها == 2 - Absorbing Submdules (Modules) and Some of Their Generalizations

اسم المؤلف: عبد الرحمن عبد الله حرفش
اسم المشرف: انعام محمد علي هادي
الموضوع العام: علوم الرياضيات
السنة: 2015
الموضوع الدقيق: الرياضيات
الدرجة: ماجستير
الجامعة: جامعة بغداد
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: Let R be a commutative ring with identity, and let M be a unitary left Rmodule. Prime ideals one of the main concepts in ring theory and many generalizations of this concept are introduced such as strongly prime ideals, almost prime ideals, weakly prime ideals, semi - prime ideals, weakly semiprime ideals and 2 - absorbing ideals. Moreover each of the above concepts generalized to submodules. Main goals in this work :  Presenting a comprehensive study of 2 - absorbing submodules and giving many new characterizations and properties related with this concept. Also we use this concept to define and study a new class of modules which is called 2 - absorbing modules.  Introducing and studying many generalizations of 2 - absorbing submodules, 2 - absorbing modules. In fact we introduce and study semi - 2 - absorbing submodules, semi - 2 - absorbing modules, Endo 2 - absorbing submodules, Endo semi - 2 - absorbing submodules, Endo 2 - absorbing modules and Endo semi - 2 - absorbing modules.  Presenting other kinds of 2 - absorbing submodules(resp.2 - absorbing modules) namely small 2 - absorbing submodules (resp. small 2 - absorbing modules ). Then Endo small 2 - absorbing submodules (resp. Endo small 2absorbing modules) are introduced and studied.

استخدام النمذجة الرياضية والشبكات العصبية للسرطان : نمو الورم والعلاج == Employ Mathematical Modeling and Neural Networks for Cancer : Tumor Growth and Treatment

اسم المؤلف: سجى عبد الرحمن عبد الجبار
اسم المشرف: لمى ناجي محمد توفيق
الموضوع العام: علوم الرياضيات
السنة: 2015
الموضوع الدقيق: الرياضيات
الدرجة: ماجستير
الجامعة: جامعة بغداد
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: تهدف الرسالة الى ما يلي : ان الهدف الاول هو تقديم وتطوير نموذج رياضي يصف نمو الورم السرطاني , والذي يمكن استخدامه لتحديد معدل نمو السرطان .والهدف الثاني للرسالة هو تصميم شبكة عصبية ذات تغذية تقدمية كتقنية دقيقة متداولة لتحديد معدل نمو السرطان, والذي يمكن استخدامه لحل معادلة النموذج. والشبكة المقترحة تحاكي اولا لتحديد معلمات معادلة النموذج, ومن ثم تحاكى لتقدير معدل النمو السرطاني .واما الهدف الثالث هو تطوير الجانب النظري لمرحلة التدريب للشبكة العصبية من خلال تحسين خوارزمية شبه نيوتن, وتحسين تعميم الشبكة المقترحة ومعالجة التوقف المبكر للشبكة ومشاكل الحدود الدنيا المحلية ايضا.واخيرا الهدف الرابع هو اختبار اداء التصميم المقترح والخوارزميات في تشخيص السرطان وعلى وجه الخصوص تشخيص سرطان المثانة, وكذلك كيفية استخدام معمارية الشبكة العصبية الاصطناعية ذات التغذية التقدمية للمساعدة في تشخيص السرطان في مرحلة مبكرة. | There are many aims of this thesis : The first aim is to introduce and develop a model equation that describes the tumor growth of cancer, which can be used to determine the rate of growth for cancer. The second aim of this thesis is to design feed forward neural network as an alternative accurate technique to predict the rate of the tumor growth for cancer which can be used to solve the model equation. The suggested network is simulating firstly to estimate the parameters of model equation, and then simulates to estimate the rate of the tumor growth. The third aim is to develop a conceptual theory of training stage for neural networks from suggested improvement of quasi Newton algorithm also improve the generalization of suggested networks and treating the early stopping and local minima problems. Finally, the fourth aim is testing the performance of the suggested design and algorithms in diagnosis of cancer with special reference to bladder cancer detection, also provides how the utilization of FFNN technique helps for diagnosis of cancer in early stages.

استخدام التقنية شبه التحليلية في حل مسائل القيم الذاتية متعددة المعلمات

اسم المؤلف: دعاء رحيم عبود
اسم المشرف: لمى ناجي محمد توفيق
الموضوع العام: علوم الرياضيات
السنة: 2015
الموضوع الدقيق: الرياضيات
الدرجة: ماجستير
الجامعة: جامعة بغداد
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: This thesis is concerned with a semi - analytic technique to find the solution of two parameters, quadratic and MPEVPs for ODE.The technique finds the two parameters, quadratic, multi parameter eigenvalue and the corresponding nonzero eigenvector which represent the solution of the problems in a certain domain.Illustration examples is presented, which provided to demonstrate the efficiency and accuracy of the proposed technique where the suggested solution compared with other methods. Many applications in mathematical physics and electromagnetic or elastic wave equations, chemical reaction theory and nanotechnology such as Mathieu differential equation are solved.Also, we give an observations for control of error, control of residual and we proposed a new formula developed to estimate the error which help to reduces the accounts processes and improve the results are improved.The existing code bvpsuite designed for the estimate the error of solution of boundary value problems was extended by a model for the computation the estimate error for the solution of the problems in thesis

تاثير اضافة مادة البايركس على بعض الخصائص الفيزيائية لمادة البورسيلن == Influence of Pyrex Addition on Some Physical Properties of Porcelain Material

اسم المؤلف: عمر عدنان جاسم
اسم المشرف: كريم علي جاسم | سوسن عبد الحسين مهدي
الموضوع العام: علوم الفيزياء
السنة: 2015
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: This study was carried out to prepare a porcelain samples of raw material 50 wt % kaolin dukhla, 25 wt % erzma sand glass and 25 wt% feldspar, boro silicate glass (Pyrex) used as a flux in the porcelain (ceramic) body, instead of feldspar, yielding a new material which has new properties with grain size equal to 53μ.Pyrex which was added to the porcelain to get the mixtures of sample. The all mixtures prepared and 10 wt % of distilled water was added, the resulting blends were die pressed of 25 MPa, to produce specimens with diameter of 25 mm and thickness of 5 mm, then they were dried and sintered for different temperatures (1200, 1250, and 1300) C° for 1 hour in an electric furnace. Physical properties measurements such as density, porosity, water absorption and length shrinkage percentage, were carried out, also mechanical properties (compression strength) and thermal properties. (Thermal conductivity and heat capacity) were measured The result of the physical properties measurement are found to be improved at increasing the ratio of Pyrex mixture, such as increase in density and shrinkage which a company with the decrease of porosity and water absorption, also the same changes were happened for these properties with increasing sintering temperature for all mixtures, and the highest increment in shrinkage have been shown at 1250 C°.The thermal conductivity and heat capacity have increased the ratio of Pyrex mixture, and there are small increment in these measurements, at increasing temperature for mixtures 3 and 4, but the increment is high for mixture no. (2).The results of mechanical properties measurements (diametrical strength) are found to be improved and increased at the increase of the ratio of Pyrex mixture and the mixture no. (3) have a highest strength. Also this improvement and increment in strength was continued for mixtures 2 and 3, with the increase of the sintering temperature whereas decreases for mixture (4) improvement in physical and mechanical properties for a new porcelain make suit usage in brick walls industry (porcelain tiles).

السليكون العشوائي للثنائي الباعث للضوء من النقاط الكميه == Amorphous silicon Light Emitting Diode Quantum Dots

اسم المؤلف: ولاء خليل جميل خليل
اسم المشرف: موفق كاظم عبد الرضا
الموضوع العام: علوم الفيزياء
السنة: 2015
الموضوع الدقيق: الفيزياء
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: في هذه الدراسة استخدمت الحسابات النظرية لنبيطة ثنائي الباعث للضوء للنقاط الكميه من السيليكون العشوائي. وعن طريق هذه الحسابات فقد تبنينا فكرة التقيد الكمي. وقد وجد ان الانبعاث الكمي الضوئي يظهر اعتمادا مهما لحجم النقاط الكمية والتي تتراوح من (١ - ٤) نانومتر. ان الكفاءة الكمية الداخلية تتاثر بدرجة الحرارة حيث تكون اكثر كفاءة عند درجة حرارة الغرفة. يمكن لفجوة الطاقة ان تتناغم وفقا للتحكم بحجم النقاط الكمية من السليكون العشوائي. وقد اظهرت النتائج الازاحة نحو الطاقا العاليه في تاثير حالة التقييد الكمي, لهيكل النقاط الكمية للسيليكون العشوائي. وهذا التقييد الكمي يجعل السليكون مرشح للعرض بكامل الوان الطيف البصري. مما يقودنا هذا السلوك البصري الى تفسير تغير مادة النقاط الكمية للسيليكون العشوائي لتصبح مادة ذات فجوة حزمية مباشرة بعد ان كانت غير مباشرة في طبيعتها الحجمية. تمت دراسة الكفاءة الكمية الداخلية بوصفها دالة الى الطول الموجي وتيار الحقن. لقد وجدنا ان النتائج المستحصلة متفقه اتفاقا جيدا مع النتائج التجريبية المنشورة. لذا, فاننا نؤكد على ان مادة النقاط الكمية من السليكون العشوائي هي خيار واعد لنبائط انبعاث الضوء المرئي والقابلة للتناغم الطاقي وذات انجازية عاليه | In this work, theoretical calculations were used by considering the amorphous silicon quantum dots light emitting diode (a - SiQDs LED) as the device of investigation. By these calculations, the effect of quantum confinement was a doped. It is found that the light emission shows significant size dependence in the range (1 - 4) nm of the quantum dots. The internal quantum efficiency is affected by temperature and it is more efficient at room temperature. The energy gap can be tuned by controlling the size of a - SiQDs. The blue shift is attributed to quantum confinement effect in a - SiQDs structure, where quantum confinements make silicon like candidate for full - color display. It led to the interpretation that the a - SiQDs material has been changed to be a direct band gap material. Internal quantum efficiency as a function of wavelength and injection current has been studied. It is found that the obtained results are in good agreement with the experimental published data. Therefore, a - SiQDs material was asserted to be a promising candidate for visible, tunable and high performance light emitting devices.

دراسة نظرية لطيف مستويات الطاقة الواطئة ولنوى خفيفة باستعمال انموذج القشرة النووي 3016S14,3014Si16,188Ne10 == Theoretical Study Of Low Lying Spectrum For Light Nuclei By Using Nuclear Shell Model 3016S14,3014Si16,188Ne10

اسم المؤلف: هدى بطرس بهنام مقادسي
اسم المشرف: هادي جبار مجبل العكيلي
الموضوع العام: علوم الفيزياء
السنة: 2015
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: ان طاقات الربط والتهيج حسبت لنوى (_8^18)Ne_10 , (_16^30)S_14 , (_14^30)Si_16 وللمستويات الدنيا باستعمال حسابات انموذج القشرة النووي ولبروتونين في القشرة S,dلنوى (_16^30)S_14 بينما لنيوترونين لنواة (_14^30)Si_(16 ) ,(_8^18)Ne_10 ولمدارات خارج القلب المغلق .عناصر مصفوفة التفاعل تم الحصول عليها من خلال استخدام جهد تفاعل USD,USDA ,USDBنتائج الحسابات النظرية لطاقات الربط والتهيج والمحسوبة باستعمال عناصر المصفوفة النظرية اظهرت تطابقا مع النتائج العملية .حسابات انموذج القشرة استعملت لفهم ودراسة خصائص المستويات الدنيا ولعدد الكتلة لنوى A=18,30 .استعمل القلب المغلق مع التفاعل المتبقي للجسمين ما بين النكليونات الخارجية O8816 ,14 14Si28 .لحالات التماثل الموجبة فان جميع التشكيلات لقشرة S,d اخذت بالحساب باعتبار ان هناك قشرة مغلقة مع جسيمين في مستويات القشرة .S,dتفاعل الجسمين الفعال للنوى اختير على اساس جهد USD,USDA,USDB .اظهرت قيم طاقات الربط والتهيج تطابق جيد مع القيم العملية .واعتبرت الجهود USD,USDA,USDB هي المدخلات الاساسية لحساب الطاقات النووية والتي تتضمن تفاعل نكليون - نكليون .الحسابات اظهرت لنا امكانية اكبر لفضاء تفاعل النكليونات كون طاقات الحالات الارضية متقاربة . | Binding and excitation energies have been calculated at low lying levels for (_8^18)Ne_10 , (_16^30)S_14 and (_14^30)Si_16 nuclei using shell - model calculation with two protons in the S - d shell for (_8^18)Ne_10 , and (_16^30)S_14 while two neutrons for (_14^30)Si_16 in orbits outside the closed core. The effective two - body matrix elements are obtained from the USDA, USDB and (USD) potential interaction. Results of calculated binding and excitation energies are show a good agreement with experimental data with calculated by using theoretical matrix elements . The shell model calculation is used to investigate properties of levels at low lying in the mass number of nuclei A =18 and 30. An inert core with a residual two - particle interaction between the outer nucleons of (_8^16)O_8 , and (_14^28)Si_14 as summed. For the positive parity states all configurations in the s - d shell are taken into account are described by a closed shell, two nucleons in the S - d shell . The effective two - particle interaction is chosen to be a described by the USD,USDA ,and USDB potential. Good agreement with experiment is obtained for the binding and excitation energies. It is considered USDA , USDB and USD potential for two - body matrix element interaction as the most input parameters to the calculation is the nuclear energies, which contains realistic two (N - N) interactions. Provided the calculation is performed in a large enough basis space, the ground - state energy will converge

دراسة خصائص التفاعل النووي (?,n) للنوى الفردية - الزوجية Z?29) ? 21) == Studying the Properties of Nuclear Reaction (?,n) for Odd - even Nucleus (21?Z?29)

اسم المؤلف: نور عادل محمد
اسم المشرف: فاطمة عبد الامير | سميرة احمد
الموضوع العام: علوم الفيزياء
السنة: 2015
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: الدراسة الحالية تركزت على دراسة الخواص النووية للتفاعل النووي (الفا, نيوترون ) لنويات الهدف ذات الاعداد الذرية الفردية وللتفاعلات ( (_21^45)Sc(α,n)(_23^48)V, (_23^51)V (α,n) (_25^54)Mn , (_25^55)Mn(α,n)(_27^58)Co , (_27^59)Co(α,n)(_29^62)C , (_29^63)Cu(α,n)(_31^66)Ga (من خلال حساب المقاطع العرضية لتفاعلات (الفا , نيوترون ) للتفاعلات المذكورة اعلاه والمنشورة في الادبيات العالمية ( EXFOR , ENDF , JEF , JEFF , GENDL) لانتقاء الطاقات الملائمة في حساب التفاعل للمستوى الارضي باستعمال على برنامج الحاسوب ( (Matlab - 7.6 وبخطوات طاقية معينة . تم رسم وجدولت النتائج المستحصلة من تطبيق المعادلات شبه التجريبية لتمثيل جميع التفاعلات التي تربط بين تغير المقطع العرضي مع مدى الطاقة المعين . بالاضافة الى حساب وجدولت بعض الخواص النووية للنظائر الموجودة في هذه التفاعلات كما وتم حساب وجدولت كل من طاقة التفاعل وطاقة العتبة لكل تفاعل ومقارنتها مع النتائج الموجودة في مركز الدراسات النووية (NNDC) وهي متوافقة معها بشكل جيد جدا . وكذلك تم حساب قدرة الايقاف باستعمال برنامج SRIMو تم حساب الحاصل النيوتروني وفقا لصيغة زكلر لكل تفاعل بالاستعانة بقدرة الايقاف . وقد استعملت قيم المقاطع العرضية لتفاعلات (الفا ، نيوترون) في حساب المقاطع العرضية لتفاعلات العكسية (نيوترون ،الفا) وللمستوى الارضي وذلك باشتقاق المعادلة شبه التجريبية لقيم المقاطع العرضية العكسية لكل من التفاعلات الاتية (_23^48)V(n,α) (_21^45)Sc , (_25^54)Mn(n,α)(_23^51)V , (_27^58)Co(n,α)(_25^55)Mn , (_29^62)Cu(n,α)(_27^59)Co , (_31^66)Ga(n,α)(_29^63)Cu وايجاد الثوابت لكل تفاعل. تم رسم وجدولت النتائج المستحصله وايجاد معادلة ملائمة للرسم التي يمكن من خلالها الحصول على مقاطع عرضية بطريقة مباشرة وسريعة وبسيطة وموثوقة | This work was concerned on study the properties of (alpha, neutron) reactions for nuclei that’s have odd atomic number in nuclear reactions [(_21^45)Sc(α,n)(_23^48)V,(_23^51)V (α,n),(_ 25^54)Mn (α,n)(_27^58)Co, (_27^59)Co(α,n)(_29^62)Cu ,(_29^63)Cu(α,n)(_31^66)Ga] , by calculating the cross sections of (alpha, neutron) reactions. The nuclear reactions were published in the world libraries (EXFOR , ENDF , JEF , JEFF , GENDL) most recent to select the suitable energies in calculating reverse nuclear reactions for ground state. In the present work, the cross sections were calculated from semi - empirical formula which were obtained and listed in tables using computer programs(matlab 7.7R2008). These formulas represent the variation of the cross section with energy, which could be used to predict the values of uncalculated cross sections. The stopping power according to Zeigler formula was used in order to obtain the neutron yield for each nuclear reaction. Neutron yield is very important to determine the best way to produce specific isotopes. The evaluated cross sections for (α,n) are used to calculate the cross sections for inverse reactions (n,α) using empirical formula of the inverse cross sections .The values of neutron energy and inverse cross sections have been drown and listed in tables. Qo - value, threshold energy, reduced mass and binding energy have been calculated and listed in tables for each reaction

تحضير ودراسة متراكبات بوليمرية مدعمة من نوع PMMA/Graphene وPMMA/ZnO النانوية == Preparation and Studying of Polymeric Reinforced Composites Type PMMA/Graphene and PMMA/ZnO Nanoparticles

اسم المؤلف: مصطفى عبد الكريم جهاد الاوجي
اسم المشرف: تغريد مسلم مريوش الساعدي
الموضوع العام: علوم الفيزياء
السنة: 2015
الدرجة: ماجستير
اللغة: العربية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: تم تحضير مساحيق نانوية بطريقة هامر وطريقة الصول - جل , اذ تم تحضير رقائق الكرافين باختزال اوكسيد الكرافين المحضر بطريقة هامر باستعمال مسحوق وقضبان الكرافيت , بينما حضر اوكسيد الزنك النانوي بطريقة الصول - جل . كما تم تحضير متراكبات بوليمرية نانوية بهياة اغشية سميكة بسمك نحو (0.206mm) وبهياة (Bulk) بطريقة الخلط والصب اليدوي (Hand lay - up) باستعمال راتنج بولي ميثيل ميثاكرليت (PMMA) كمادة اساس ورقائق الكرافين او اوكسيد الزنك كمادة تدعيم وبنسب وزنية (0.1,0.3,0.5,1,2)% .تم اجراء الفحوص التشخيصية للمساحيق النانوية والاغشية النقية والمدعمة باستخدام تقنيات (XRD,SEM,EDX,DLS) . اظهرت نتائج قياسات حيود الاشعة السينية ان جميع المساحيق النانوية المحضرة ذات تركيب بلوري متعدد التبلور ومن النوع السداسي , واظهرت انماط حيود الاشعة السينية ذروتين بالنسبة لاوكسيد ورقائق الكرافين بالمدى الزاوي (5 - 70)ᵒ للسطح (001) لاوكسيد الكرافين و(002) , (100) لرقائق الكرافين , بينما اوكسيد الزنك اذ ظهرت له ثمان ذروات عند المدى الزاوي (20 - 80)ᵒ للسطوح الثلاثة الاكثر شدة هي (100),(002),(101), كما اظهرت نتائج الحيود ان للاغشية النقية والمدعمة هيمنة الاتجاه (002) بالنسبة للاغشية المدعمة برقائق الكرافين ، بينما يهيمن الاتجاه (100) بالنسبة لاغشية المدعمة باوكسيد الزنك النانوي , كما اظهرت حسابات الحجم الحبيبي ان هناك تناقصا واضحا بزيادة نسب التدعيم .اوضحت نتائج فحوصات (DLS) ان الحجم الحبيبي لرقائق الكرافين كان بحدود 200nm , بينما كان الحجم لاوكسيد الكرافين 20nm واوكسيد الزنك بحدود 15.8nm , اما صور (SEM) فقد اظهرت اوكسيد الكرافين بشكل تكتل زغبي بينما الكرافين بشكل رقائق او صفائح اما اوكسيد الزنك بشكل شبه كروي وقضبان نانوية ذات اطوال مختلفة . اما بالنسبة لفحص (EDX) فقد ظهرت قمة عالية للكاربون عند (1.8 KeV) لمسحوق الكرافين واوكسيد الكرافين كما ظهرت قمة للاوكسجين (0.53KeV) تعود لاوكسيد الكرافين , اما اوكسيد الزنك فقد اظهر قمة عالية عند (1.1KeV) تعود للزنك وقمة عند (0.53KeV) تعود للاوكسجين .كما تضمن البحث دراسة الخواص البصرية للاغشية المحضرة منها قيمة فجوة الطاقة البصرية للانتقالات الالكترونية المباشرة المسموحة , وكذلك تم حساب معامل الامتصاص والانعكاسية ودراستها من خلال طيفي الامتصاصية والنفاذية ضمن مدى الاطوال الموجية (300 - 1100)nm , واظهرت النتائج ان قيم فجوة الطاقة البصرية تقل مع زيادة نسب التدعيم بالنسبة للكرافين واوكسيد الزنك ZnO.شملت نتائج القياسات البصرية ايضا حساب الثوابت البصرية المتمثلة (معامل الانكسار , ومعامل الخمود , وثابت العزل الكهربائي بجزايه الحقيقي والخيالي ) , ووجد ان هناك زيادة في قيم معامل الخمود ومعامل الانكسار بزيادة نسبة التدعيم .كما تم دراسة الخواص الحرارية والميكانيكية للمتراكب البوليمري المدعم بالمواد النانوية , ولوحظ ان الصلادة ودرجة الانتقال الزجاجي تزدادان بزيادة نسبة التدعيم . | In this study , nanopowders prepared by using Hummer's and Sol - Gel methods , Graphene was prepared by Hummer's method using graphite powder and rods graphite , while zinc oxide was prepared using Sol - Gel method. Nanocomposites were prepared in form of thick films with thickness (0.206)mm and (Bulk) by blend and (Hand lay - up) methods using resin (PMMA) as a matrix and graphene flakes or zinc oxide as reinforced materials . The nanopowders , pure and reinforced films were characterized by using the techniques (XRD,SEM,EDX,DLS) , the results of XRD exhibit in the angular range (5 - 70)ᵒ grahene oxide with surface (001) while graphene flakes have two peaks in (002) and (100) , zinc oxide in angular range (20 - 80)ᵒ exhibits eight peaks with three high intensity surfaces (101) , (002) and (100). While XRD results showed the pure and reinforced films with dominance of (002) surface in films reinforced by flakes and dominance of (100) surface in films reinforced by nano zinc oxide . DLS test showed that the particles size of graphene flakes is in the range 200nm and graphne oxide is in 20nm while zinc oxide is 15.8nm . SEM images showed graphen oxide has the form of agglomerated and graphene like flakes or plates while ZnO has semispherical and nanorods form with different lengths. EDX test showed that all powders have strong peaks , high carbon peak exhibits at (1.8KeV) while zinc exhibits at (1.1 KeV) with oxygen peak at (0.53KeV) for both graphene oxide and ZnO , and we saw other small peaks represent impurities with small weight percentages that exhibited during the preparation . Optical properties was studied for preparing thick films from absorptance and transmittance spectrum for the range (300 - 1100)nm. Results showed the energy gap is decreased by the increase of the concentration of reinforced material , the reflectance and the absorption coefficient were calculated by this spectrum .And we calculated other optical constants like refractive index, extinction coefficient and dielectric constant in its two parts .Also we saw the extinction coefficient and refractive index increase with the increase of the concentration.This work included thermal and mechanical properties. The results showed the hardness and the degree of glass transition which increased with the increase of the concentration .

نماء وميزات بلورات K2SO4 المطعمة بايونات النحاس Cu+2والحديدFe+2 == Crystal Growth and Characterization of Doping K2SO4with Copper Cu+2and Ferrite Fe+2 ions

اسم المؤلف: مريم عيسى فيصل
اسم المشرف: طارق عبد الرضا علوان الظاهر
الموضوع العام: علوم الفيزياء
السنة: 2015
الموضوع الدقيق: الفيزياء
الدرجة: ماجستير
اللغة: العربية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: نماء بلورات احادية لكبريتات البوتاسيوم النقية والمطعمة بايون النحاس (Cu+2) وايون الحديد (Fe+2) الناتجة عن كبريتات البوتاسيوم K2SO4 بوصفها مادة اساس وباضافات محددة من كبريتات النحاس CuSO4.5H2O وكبريتات الحديدوز FeSO4.7H2O بنسب وزنية (1% ,2% ,3% ,5%)بوساطة تقنية التبخر البطيء للمحلول المائي في درجة حرارة الغرفة لكونها سهلة وتعطي نتائج ذات جودة مقبولة , وبمولاريةM=1 وبابعاد (9x3x2)mm3 لبلورة K2SO4 النقية وبابعاد (28x18x4)mm3 بعد اعادة التبلور , ودراسة اثر التطعيم في النماء البلوري والخصائص التركيبية , ففي حالة التطعيم بكبريتات النحاس اذ كانت ابعاد اكبر بلورة بعد اعادة التبلور عند التطعيم بنسبة 3% ,2%)) وهي (14x12x9) mm3 (12x11x12)mm3 على التوالي , اما في حالة التطعيم بكبريتات الحديدوز المائية كانت ابعاد اكبر بلورة بعد اعادة التبلور هي في النسبة 3%, اذ اظهرت الدراسة اهمية اعادة نماء البلورات لمرة اولى وثانية ومدى تحسن الخصائص البلورية الناتجة عن هذه العملية من حيث النقاوة والحجم والهيئة , فنلاحظ ان المادة في الحالة النقية تكون اكبر حجما بالابعاد , وتم التاكد من التركيب البلوري للبلورة النقية , وللبلورات المطعمة اعتمادا على مخططات حيود الشعاع السيني وتحليل بنية البلورات بوساطة مقياس حيود الاشعة السينية للمسحوق واستخدام تصفية ريتفيلد لحساب معلمات خلية الوحدة unit cell وثوابت الشبيكة للبلورات المنماة. تمتلك بلورة K2SO4 النقية قبل التطعيم النظام البلوري المعيني المتعامد المحاور (Orthorhombic) وثوابت خلية الوحدة المطابقة تقريبا لبطاقة JCPDSوالدراسات السابقة , اما للبلورات المطعمة تشير مخططات XRDالى تعرضها لبعض التغيرات في البناء البلوري وتحول النظام من المعيني المتعامد المحاور الى احادي الميل (Monoclinic) في حالة التطعيم بالنحاس بنسبتي 2% ,3% , ودراسة الانماط الاهتزازية للبلورات المنماة بتقنية FTIR اذ نلاحظ حدوث امتصاص للحزمة العريضة عند القيمة 1097 cm - 1 للبلورة النقية K2SO4 والمطعمة بتزحزح قليل يتراوح بين 3 ± عن قيمة العدد الموجي في الحالة النقية وهو ما يميز انماط الاهتزاز للمجموعة الكبريتية , واخيرا درست الانتقالات الطورية من اختبار مسعرية المسح التفاضلي DSC اذ لوحظ تغير الطور لبلورة K2SO4 في درجة الحرارة 581˚C اما العينات المطعمة فنلاحظ حدوث تزحزح بمقدار ±2 عن العينة النقية , وحساب السعة الحرارية لهذه البلورات من مخططات اختبار DSC . | Single Crystal of Pure and Cu+2 , Fe+2 doped potassium sulfate a rising from potassium sulfate as a material basis and additions specific of copper sulfate CuSO4.5H2O and ferrous sulfate FeSO4.7H2O proportions by weight (1% ,2% ,3% ,5% ) were grown from aqueous solutions by the slow evaporation technique at room temperature, for easy being and give acceptable quality results with Normality M=1 , with dimension of (11x9x4) mm3(9x3x2) mm3 and dimensions (28x18x4) mm3 after re - crystallization to crystallize pure K2SO4 , and study The influence of doping on crystal growth and synthetic properties crystalline, after doping ,in the case of doping of copper sulfate it was the biggest dimensions of crystal doped by 3% 2% after re - crystallization was (14x12x9)mm3 (12x11x12)mm3, respectively , also in the case of dopants ferrous sulfate was larger dimensions crystal after re - crystallization at in the ratio of 3% , as the study showed the importance of re - crystallization of crystals - time first and second and the extent of improvement in characteristics of crystalline resulting from this process in terms of purity, size and body , We note that the Crystal in the pure case be larger dimensions, Structure analysis of the grown crystals were obtained and confirmed by X - Ray powder diffraction measurements. The diffraction patterns were analyzed by the Rietveld refinement method to calculate the unit cell parameters of these crystals , XRD measurements show the crystal system of orthorhombic, Space group (Pnma) and constants of the unit cell, the agreement to the card JCPDS and previous studies, XRD schemes indicate to occur some of the changes in the construction of crystal Structure for dopant crystal and transformation from Orthorhombic to Monoclinic system at the case of dopante copper 2%, 3%, and study the vibrational patterns for the grown crystals by technology FTIR , where we note the occur uptake of broadband at the value of number wave 1097 cm - 1 for pure Crystal K2SO4 , and dopants Crystals occur few Shift about 3 ± from the value of the wave number from the pure case. It was that distinguishes the vibration patterns of the group sulfur, finally studied phase transitions by test Calorimetry differential scanning DSC , a change phase was observed to crystal K2SO4 at temperature 581˚C and dopants Crystals we note the occur Shift about ± 2 for the pure sample , calculate the heat capacity for these Crystal from DSC analysis schemes.

تحضير SnO2 النانوي ودراسة تاثير التشويب على الخواص التركيبية والبصرية == Preparation SnO2 nanoparticles and Study the Effect of Doping on Structure and Optical Properties

اسم المؤلف: كرار امين قدوري محمد
اسم المشرف: طارق عبد الرضا علوان الظاهر
الموضوع العام: علوم الفيزياء
السنة: 2015
الدرجة: ماجستير
اللغة: العربية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: تم في هذا البحث تحضير مسحوق SnO2 النانوي النقي المحضر من املاح القصدير المتمثلة بملح SnCl4.5H2O بطريقة الصول - جل بثلاثة مذيبات مختلفة وهي الماء، والميثانول، والايثانول، وتم اجراء عملية التلدين عند درجة حرارة (400°C) .تم اختيار المذيب الايثانول لاعطائه اكبر كمية من المسحوق ومطابقته للملف ذي الرقم (JCPDS : 41 - 1445) لتحضير العينات المشوبة (بالنيكل والمغنيسيوم والكادميوم) كل على انفراد وبثلاثة تراكيز (5, 10 و%15) من كل عنصر ثم اجريت عملية تلدين لهذه العينات لدرجة (700°C).اظــهرت نتائج حـيود الشعاع السيني ان جــميـع العينات المحـضـرة تمتلك نظاما رباعيا متعددة التبلور وفحصت العينات للمدى الزاوي (°20 - °100)، وظهرت السطوح الاربعة الاعلى شدة وهي ((110, (101), (200), 211))، تم حساب الحجم الحبيبي بطريقة ديباي - شيرر وبطريقة وليامسون - هول، وبينت النتائج ان حجم الحبيبات يقل بزيادة نسبة التشويب، كما تم حساب العديد من المعلمات التركيبية كثوابت الشبيكة وفسحة السطوح، والكثافة، والمساحة السطحية النوعية، وعدد خلايا الوحدة، وكثافة الانخلاعات، والاجهادات المجهرية وعامل التشكيل وعامل طبيعة السطح. اوضحت نتائج فحوص (AFM) طبيعة السطح للعينات المحضرة، وقد تم حساب معدل الحجم الحبيبي، ومعدل الخشونة، وقيمة جذر مربع المعدل(RMS) وكانت مختلفة من حيث معدل خشونة السطح. حيث تقل الخشونة بزيادة نسبة التشويب، ويقل معدل قطر الحبيبات بزيادة نسبة التشويب التي اتفقت مع نتائج حيود الشعاع السيني وكانت تتراوح ما بين (127.71 - 69.64) nm، وقد اظهرت صور (SEM) ان اشكال الحبيبات النانوية للنماذج (P4,N3,M3,C3) كروية او شبه كروية متجمعة بهياة عناقيد وظهر البعض منها بشكل متكتل. اما بالنسبة لفحص (EDX) فقد اظهرت جميع العينات قمة عالية عند ~3.5) keV) للقصدير مع ظهور قمم صغيرة لعنصر الكلور والبوتاسيوم التي عدت كشوائب بنسب وزنية ضئيلة جدا نتيجة عملية التحضير للعينة النقية، اما العينات المشوبة فقد اظهرت قمم مادة التشويب بالاضافة الى القصدير الا ان الاوكسجين لم يظهر في فحص (EDX).ومن خلال تسجيل طيـف الامتصاص لمحلول SnO2 وضـمن مــدى الاطــوال الموجـية (300 - 900 nm)، اوضحت النتائج ان الامتصاصية تزداد بزيادة نسبة التشويب لجميع العينات، اما فـجـوة الـطاقة البصرية للانتقال الالكتروني المباشر الـمـسـمـوح باستعمال معادلة (Tauc) وباستخدام معادلة (Kubelka - Munk) فقد وجد انها تقل بزيادة نسبة التشويب. | In this research, pure SnO2 Nanopowders were prepared from tin salt (SnCl4.5H2O) by sol - gel method using three different solvents; water, methanol and ethanol. The preparered powders annealed at temperature (400°C). according to the result of prepared powder, the sample of ethanol as a solvent is taken into consideration due to the greater amount of the powder is produced and it’s in a good agreement with the File No. (JCPDS : 41 - 1445). The preparation of doped samples is performed using ethanol as a solvent with each one of the dopants (Nickel, Magnesium and Cadmium) with three percentages (5, 10 and 15)% of each element. Then nine prepared doped samples as well as the pure one were annealing at (700°C).XRD results show, all prepared samples have polycrystalline tetragonal crystal system. The scan of x - ray in the range of Bragg’s angle (20 - 100)° which revealed the four highest intensity peaks, (110),( 101),( 200) and ( 211)planes. From the diffraction pattern of each sample, the crystallite size is calculated by Debye - Sherrer and Williamson - Hall methods. Their results showed that grain size decreases with increasing ratio of doping concentration, also there has been many parameter likes; lattice constants, interplanar distance, specific surface area, number of unit cells, intensity, dislocations density and macrostrain which are calculated. AFM test revealed the morphology of the prepared samples. Their grain size, roughness and average root mean square value (RMS) are different for each sample. Surface roughness decreased with the increase of the dopant percentage. The average grain size was ranging between (69.64 - 127.71) nm and is decreased with the increase of dopant percentage and this show a good agreement with the XRD results. SEM for the sample (P4, N3, M3 and C3) revealed spherical or semi - spherical nanoparticles agglomerate in the form of a cluster. While EDX test shows a high peak at (~ 3.5)KeV of the Tin, with small peaks of chlorine and potassium which are considered as impurity and that is due to its small quantity which is resulted from the process of preparation of pure sample. In the doped samples, the peaks of dopant elements appeared in addition to that of tin, but the oxygen does not appear.UV spectra for all samples are performed by dissolving some amount of the powder in the double distilled water in the range (300 - 900) nm, their results show the absorbance increases with the proportion of dopant concentration of all samples. The optical energy gap for allowed direct transition are calculated by using Tauc and Kubelka - Munk equations, which decrease with the increase of dopant percentage.

دراسة الخصائص التركيبية والكهربائية والمغناطيسية للفرايت النانوي ذي التركيب المغزلي المحضر بطريقة السول (NixCu0.2Zn0.8 - xFe2O4) - جل ذات الا حتراق التلقائي == Studying Structural , Electrical and Magnetic Properties for Nano Spinel Ferrite of (NixCu0.2Zn0.8 - xFe2O4) Prepared by Sol - Gel Auto Combustion Method

اسم المؤلف: عمار عيسى عباس نجم الربيعي
اسم المشرف: احمد رفيق عبد المجيد
الموضوع العام: علوم الفيزياء
السنة: 2015
الدرجة: ماجستير
اللغة: العربية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: In this research , Nano spinel ferrite (NixCu0.2Zn0.8 - xFe2O4) was synthesized using sol - gel auto - combustion and flash combustion methods .Nineteen samples were prepared and their studies were divided into three parts. Study the effect of citric acid in preparation of Nano ferrite (Ni0.1Cu0.2Zn0.7Fe2O4) by changing the molar ratio of adding fuel to any sample and the five samples were prepared from (C series). The structural properties of samples were studied using x - ray diffraction technique (XRD) and scanning electron microscope (SEM) which showed that the obtained ferrite possesses spinel cubic phase for all used molar ratios , besides when the concentration of adding fuel was increased leads to decrease in grain size and theoretical density , increase in dislocation density and the surface area. Then the molar ratio (1 : 1 M) was chosen as the best adding ratio due to that the obtained ferrite at this ratio possesses best texture coefficient with small grain size and best internal strain by comparing with the other ratios.  Study the influence of substitute (Zn+2) ion by (Ni+2) ion on the structural , electrical and magnetic properties of Nano ferrite powder (NixCu0.2Zn0.8 - xFe2O4)(0.1≤X≤0.7) synthesized using sol - gel auto - combustion method , there are seven samples were prepared (A) series and tested by two types of structural test included analyzer x - ray diffraction and scanning electron microscope, the results exhibited forming the spinel phase for all samples in spite of the substitute of (Zn+2) ion by (Ni+2) ion, and the increase of (Zn+2) ions concentration leads to decrease in the grain size and increase in theoretical density. Then the ferrite powder was divided in two groups, the first was pressed into the pellet shape which was used in electrical tests and the second group was pressed into the rings shape which was used in magnetic tests. The two faces of the pellets in first group polished by silver paste material in case to obtain a ceramic capacitors that subjected to electrical tests which included the measurement of dielectric constant , dielectric loss coefficient, alternating electrical conductivity and direct electrical conductivity ,and the study of magnetic properties for the rings samples included measurement of hysteresis loop , selfinduction, initial permeability and the relative loss factor. The results of electrical tests exhibited decrease in dielectric constant with frequency increase at room temperature , and dielectric constant increases at certain ratios of adding (Zn+2) ions and decreases at other ratios. However , the dielectric loss coefficient its fall when increasing frequency until reaches its lowest value at the high frequencies values and so it is various when the concentrations of (Zn+2) ion were changed .and the measurement of alternating electrical conductivity displaying it increases with the increasein frequency and it values disparity with the change of (Zn+2)ion concentration , in other hand the direct electrical conductivity increase with substituting (Zn+2) ion concentration increases. The magnetic tests results exhibited that the ratio (X=0.3) with chemical formula (Ni0.3Cu0.2Zn0.5Fe2O4) possesses a significant magnetic properties when compared with other samples because it has the highest initial permeability with lowest relative loss factor and it has best hysteresis loop so that it realized conditions for using it as a cores in transducers and electrical motors. Study the influence of substituting (Zn+2)ion by (Ni+2) ion on the structural properties of Nano ferrite (NixCu0.2Zn0.8 - xFe2O4)(0.1≤ X≤ 0.7) synthesized using flash combustion method, there are seven samples were prepared (F) series tested by two types of structural tests included xray diffraction and scanning electron microscope tests , and the results exhibited form the spinel phase for all samples and no other phases were presented and observed that structural results were agreed with these obtained from sol - gel auto - combustion method.

الخواص الكهربائية والتركيب الدقيق لمقاوم اوكسيد الخارصين السيراميكي المتغير المطعم بالاتربة النادرة == Electrical Properties & Microstructure Of ZnO - Based Varistor Ceramics Doped With Rare Earth

اسم المؤلف: عادل اسماعيل كاظم
اسم المشرف: ايسر جمعة ابراهيم | عبد الحميد رحيم مهدي
الموضوع العام: علوم الفيزياء
السنة: 2015
الموضوع الدقيق: الفيزياء
الدرجة: دكتوراه
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: يعد اوكسيد الخارصين (ZnO) السيراميكي مادة شبه موصلة نوع - n، ويلعب دورا هاما في مدى واسع من العمليات الصناعية والمنتجات التجارية.ان من اكثر الاستعمالات اهمية استعماله لحماية الدوائر الكهربائية والمعدات الالكترونية من الجهد الزائد المدمر نتيجة البرق او الناتج من الارتفاع الكبير والمفاجيء في قيم الجهد الكهربائي, وتسمى المقاوم المتغير المعدني (Metal Oxide Varistor MOV) . يعد المقاوم المتغير نبيطة ذات سلوك غير اومي وخواصه الكهربائية تشبه تقريبا في عملها ثنائي زينر. لغرض دراسة وتوصيف مركبات مقوم اوكسيد الخارصين السيراميكي المتغير وتحسين خواصه الكهربائية, تم تحضير مركباته باضافة بعض الاكاسيد المعدنية وهي Bi2O3، Sb2O3، Co3O4، Cr2O3، وMnO2, حيث تم اختبار تاثيرها لوحدها اولا, وثانيا تم اضافة اكاسيد الاتربة النادرة (M2O3) مع الاكاسيد المذكورة اعلاه واختبار تاثيرها على المقاوم المتغير, حيث ان (M=Dy, La,Y) وبتراكيز مولية ( *10 - 3(1,5,10)).تمت عمليات التحضير والسيطرة على التركيب الدقيق عن طريق التحكم بظروف عمليات الحرق بدءا من عملية الاعداد بخلط اوكسيد الزنك مع الاكاسيد المضافة ومن ثم الحرق في درجة حرارة 600℃ وبمعدل 5 ℃⁄min في الفرن ولمدة ساعتين للعينات جميعها وذلك لازالة الغازات والرطوبة من المساحيق. بعد عملية الحرق تم كبس المساحيق بشكل اقراص بقطر 15mm وسمك 2mm تقريبا تحت ضغط يساوي 25MP.بعد عملية الكبس اجريت عملية التلبيد (تفاعلات الاطوار الصلبة والاطوار السائلة) بدرجات حرارة مختلفة ( 1050, 1100, 1150 ℃ ) وزمن ثابت للعينات جميعها مقداره ساعتين للحصول على الاشكال النهائية والوصول الى الخصائص المطلوبة.تمت دراسة بعض الخواص الفيزيائية للعينات المحضرة وهي الكثافة والمسامية والخواص التركيبية وذلك لغرض تقييم تاثير الاكاسيد المضافة وظروف التحضير على سلوك التطبيق الصناعي للعينات.وقد تبين ان مقدار الكثافة النسبية والمسامية تتاثر بدرجة حرارة التلبيد وبنسب تراكيز اكاسيد الاتربة النادرة المضافة ونوعها,فقد ازداد مقدار الكثافة بازدياد درجة حرارة التلبيد ونسبة او تركيز اكاسيد الاتربة النادرة المضافة ونتيجة لذلك فقد نقص مقدار المسامية.لقد اعطى اختبار التركيب المجهري للمادة المحضرة رؤية واضحة عن الانتشار والنمو الحبيبي , وان نتائج اختبار الاشعة السينية (XRD) اوضحت ان التركيب البلوري لها معيني قائم كما ان قيم (a, b, c) وحجم خلية الوحد قد ازداد بزيادة درجة حرارة التلبيد ونسب تراكيز الاكاسيد المضافة ونوعها.اظهرت الحبيبات النانوية والميكروية ضمن البحث الحالي تاثيرا كبيرا على الخصائص الكهربائية المدروسة والتي صممت لها اداة في المختبر لقياس معامل السلوك اللاخطي, مقدار جهد الانهيار , تيار التسرب, قابلية امتصاص الطاقة , انحدار الجهد وجهد الحدود الحبيبية.حيث تبين ان معامل السلوك اللاخطي يزداد بازدياد تركيز الاكاسيد المضافة وارتفاع درجة حرارة التلبيد ومن ثم يبدا بالنقصان بعد درجة (1100℃) بسبب تطاير وتبخر اوكسيد البزموث وطور(. (Zn7Sb2O12 بينما نقص مقدار جهد الانهيار وقابلية امتصاص الطاقة وانحدار الجهد بازدياد درجة حرارة التلبيد,اما تيار التسرب فقد ازداد مقداره بازدياد درجة حرارة التلبيد, وكذلك بالنسبة لجهد الحدود الحبيبية فقد ازدادت قيمها بازدياد درجة حرارة التلبيد. | ZnO is a ceramic material which tends to intrinsically form as an n - type semiconductor material, which plays an important role in a wide range of industrial processes and commercial products.One of most important usages is a Surge protection device which used to protect power and electronic equipment from the destructive transient overvoltage which arises from lightning or other large - magnitude surge, this device is called metal oxide varistor (MOV).Varistors are voltage dependent, non - ohmic devices whose electrical characteristics are almost similar to back - to - back Zener diodes.Improvement ZnO varistor performance accomplished by doping it by some metal oxides, Bi2O3, Sb2O3, Co3O4, Cr2O3, and MnO2, where they were testing their effect alone first, and second was added rare earth oxides (M2O3) with oxides mentioned above and test their effect on varistor, where (M = Dy, La, Y) and molar concentrations (10 - 3, 5*10 - 3, 10*10 - 3)The preparation process starts from mixing ZnO with additives, calcination at 600℃ in a furnace to remove the gases and the humidity from the powders. Then the calcined powders uniaxially pressed into discs (pellets) of 15 mm in diameter and 2 mm in thickness under a pressure equals to 25MP. After pressing the green pellets sintered under different temperatures (1050, 1100, 1150℃) and a fixed time to accomplish the final shapes and reach the desired properties of the samples.Then the densities of the samples were measured by using Archimedes Principle with mercury liquid to calculate the relative density and the porosity of each sample, and to study the effect of the sintering temperature and REO concentration, which already be obvious the effect of them. The microstructure test of the material prepared gave a clear vision for the diffusion and grain growth, although the results of XRD test showed that the crystal structure is an orthorhombic, and the values of (a, b, c) and the size of a the unit cell has been increased with increase the sintering temperature and ratios of the concentration of oxides added and kind.Micro and nano grains within the present research showed a significant effect on the studied electrical characteristics, which designed a tool in the laboratory for it and to measure the nonlinear coefficient, the amount breakdown voltage, leakage current, the potential gradient, the energy absorption capability, and the voltage per grain boundary. It was found that the nonlinear coefficient increases with the increasing of REO concentration added and increasing sintering temperature and then starts decreased after degree (1100℃ ) due to volatilization and evaporation of bismuth oxide and spinel phase (Zn7Sb2O12).The amount of breakdown voltage, potential gradient, energy absorption capability decreased with rising the sintering temperature, while the leakage current has been increased with increasing the sintering temperature, as well as the voltage per grain boundary has been increased with increasing of the sintering temperature.

دراسة الصفات الحرارية والميكانيكية وعمر الاداء PVC لبوليمر == Study of the Thermal, Mechanical Properties and Lifetime of PVC Polymer

اسم المؤلف: صهيب صباح احمد
اسم المشرف: وداد حمدي جاسم | محمد عبد النبي ثجيل
الموضوع العام: علوم الفيزياء
السنة: 2015
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: In this work, mechanical behavior of PVC product like pipes with different origins (K.S.A and Egypt) and Turkey doors with different manufacturing (Nova and Firat) which are used in Iraqi markets were studied.The objective of this work was to study the mechanical properties like ultimate tensile strength, Young's modulus, elongation at Max., elongation at break, impact strength, flexural strength and hardness of the pipes and doors.The experimental results show that K.S.A pipes exhibited maximum ultimate tensile strength and Young's modulus than that the Egypt pipes.However, the Egypt pipes exhibited maximum elongation at Max. and elongation at break when compared with K.S.A pipes.All the tensile properties of Firat doors are greater than that of Nova doors.Comparison of the flexural strength of pipes and doors. The pipes have the same flexural strength but the Firat doors have maximum value than Nova doors.Egypt pipes have a higher impact strength than K.S.A pipes. While the Firat doors have a higher impact strength than Nova doors. The experimental results of hardness Shore D indicated that K.S.A pipes exhibited maximum hardness number (83.7) than Egypt one, while the Firat and Nova doors have the same values.In this study, thermal properties of Firat and Nova have been evaluated, firstly by thermal conductivity and second by thermal stability and degradation. The Firat doors have better thermal conductivity than that of Nova doors. From the thermogravimetric analysis at different heating rates (2, 5, 10, 20 and 40 °C/min). The Firat doors have a higher thermal stability than Nova one.The Egypt pipes exhibited more thermal stability than the K.S.A pipes.From the TGA curves the activation energy of pipes and doors are determined at different conversion levels. At 30% conversion level when the mechanism of degradation would be stable and the value of activation energy of Egypt pipes and Firat doors is (108.35 KJ/mole) when it is (101.39 KJ/mole) for K.S.A pipes and (98.35 KJ/mole) for Nova doors. Thermogravimetric analysis (TGA) provides a method for accelerating the lifetime testing of polymers so that short - term experiments can be used to predict in use lifetime.The lifetime is decreased with increase of the temperature, at fixed temperature like 70 °C the lifetime of Egypt pipes is (≈100 years) while lifetime of K.S.A pipes is (≈21 years). At the same temperature (70 °C) the lifetime of Firat doors is (≈72 years) while the lifetime of Nova doors is (≈21 years).Thermomechanical analysis (TMA) test showed the glass transition temperature (Tg) and softening point (Ts) for pipes and doors. The K.S.A pipes have value for Tg and Ts higher than that of Egypt pipes, while the Firat and Nova doors have the same values.

الخواص التركيبية والبصرية والكهربائية لاغشية اوكسيد النيكل المحضرة بطريقة الترذيذ كمتحسس غازي == The structural, optical and electrical properties of NiO films prepared by RF - Sputtering as gas sensor

اسم المؤلف: زينب طارق عبد الحميد
اسم المشرف: قاسم عزيز محمد | محمد عبد النبي
الموضوع العام: علوم الفيزياء
السنة: 2015
الدرجة: دكتوراه
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: The structural, optical, electrical, and gas sensing properties of nickel oxide have been studied. The structural properties of the deposited films were made using XRD, SEM and AFM. The NiO films have been prepared with different thicknesses (100, 150 and 200) nm on glass, Si and Al2O3 substrates, using RF - sputtering at 100°C substrate temperature. The electrical and optical parameters of the NiO films were characterized using Hall Effect and transmittance measurements.The X - ray diffraction result indicates that the films are of polycrystalline in nature with cubic structure. The grain size of the nanoparticales observed at the surface depended of films thicknesses, where 200 nm has smallest average grain size 85.5 nm and RMS increased with increasing of thicknesses.The optical characterization shows that the film has band gap that ranged in between 3.6 eV to 3.9 eV, the average transmittance of films was found to be ranged of 60% to 85% in the VIS - IR regions. The dark conductivity of NiO films has been studied as a function of film thickness, crystal structure transformation and temperature with particular regard to gas sensitivity in CO2, NO2, CO, NO and the ethanol vapor. The electrical properties were found to be dependent on the film thickness.I - V characteristics for NiO films at (air, vacuum, N2, O2andCO2) gases before and after annealing were investigation. It would appear from our result that the diminution of the dark conductivity after annealing may be due to the surface contaminations adsorbed on the surface of the NiO film during film preparation or from ordinary atmospheric air.The resistivity of the NiO thin films decreased with increasing of thicknesses, from 1.5x105 to 5.4x104 (Ω.cm), which is related to the increase of carrier concentration with film thickness. The results of measurements of NiO thin films show that these films have good conductivities and results obtained from Hall Effect indicate that the NiO films were (p - type).It was found that the sensitivity to other gases differs for different film thicknesses and working temperature. Furthermore, NiO films exhibits high and fast response to NO2 gas at 200°C, which makes it a promising candidate for a poisonous gas sensing.

تقييم المقاطع العرضية لليورانيوم للتفاعلات المستحثة بالنيوترون == Cross Sections Evaluation of Uranium for Neutron Induced Reactions

اسم المؤلف: روناك اكرام علي
اسم المشرف: ايمان طارق العلوي
الموضوع العام: علوم الفيزياء
السنة: 2015
الموضوع الدقيق: الفيزياء
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: لقد تم في هذا البحث حساب قيم المقاطع العرضية لنظائر اليورانيوم (A=230 - 238) للتفاعلات المستحثة بالنيوترونات التالية ,,,(n,f), (n,tot), (n,el), (n,inl), (n,2n), (n,3n), (n,γ), (n,p), (n,t), (n,d), (n,α), (n,2α),and (n,2p)المقاسة بفترات مختلفة من الطاقة حيث ان هذه القراءات تم اخذها من الوكالة الدولية للطاقة الذرية (IAEA ) ومن المكتبات المشهورة عالميا مثل EXFOR, CINDA, ENDF, JEFF, JENDL,ROSFOND,CENDL,WIND, TENDL, BROND, IRDF, EAF وقد تم قياسها في الفترة الاولى من منتصف القرن الماضي وحتى اخر سنوات الماضية .لقد تم تحليل المديات الكاملة للطاقة لكل تفاعل وقد تم اعادة حساب وتقييم المقاطع العرضية ضمن فترات صغيرة مختلفة حسب مديات الطاقة للنيوترون القاصف مع الاخطاء المرافقة لها. قد تم وضع صيغ رياضية لمتعددة الحدود في معظم التفاعلات والتي تربط بين تغيير المقطع العرضي مع الطاقة والتي يمكن استخدامها للتنبىء بقيم المقاطع العرضية غير المحسوبة. لقد تم حساب قيمة Q - للتفاعل وطاقة الربط وطاقة العتبة وفرق الكتلة وعامل الرص لكل تفاعل ولكل عنصر هدف. ان التقييمات اعتمدت بشكل رئيسي على حسابات نموذج الجهد البصري لقد اعتمدت الحسابات على معاملات الجهد البصري النووي حيث تم اختيار وجمع المعلومات من مكتبة (RIPL) التابعة للوكالة الدولية للطاقة الذرية. لقد قمنا بدراسة صيغتين مختلفتين لنموذج الجهد البصري حيث ان الصيغة الاولى تسمى نموذج الجهد البصري القياسي والمعاملات ماخوذة من مكتبة Beijing والصيغة الثانية لنموذج الجهد البصري قد تم حسابها بتحديد ثلاث مديات طاقية. لقد قمنا بدراسة نسبة التفاعل (n,f) لكل نظير من نظائر اليورانيوم نسبة الى يورانيوم - 235 والذي يعتبر نموذج قياسي. لقد قمنا بحساب هذه النسبة لجميع التفاعلات المتوفرة لدينا وليس فقط تفاعل الانشطار واحتسبناها نسبة الى يورانيوم - 235.حساب اخر تم اضافته الى هذه الدراسة وهو دراسة تاثير التلوث لوليدة اليورانيوم - 237 والتي هي نبتونيوم - 237 بعمر نصفي 6.8 يوم وكذلك حساب الفيض النيوتروني لكل منهما. | The cross sections of Uranium isotopes (A=230 - 238) for the (n,f), (n,tot), (n,el), (n,inl), (n,2n), (n,3n), (n,γ), (n,p), (n,t), (n,d), (n,α), (n,2α),and (n,2p) reactions are calculated with different energy intervals which are collected from International Atomic Energy Agency (IAEA). The available cross sections data for the reactions mentioned above are collected from the well known international libraries like EXFOR, CINDA, ENDF, JEFF, JENDL, ROSFOND, CENDL, WIND, TENDL, BROND, IRDF, EAF and measured during the period from the middle of the last century up to several years ago.The cross sections are reproduced in fine steps of incident neutron energy in different intervals with the corresponding errors. The recommended cross sections for all available experimental data have been calculated for all considered reactions mathematical representative equations for all these reactions are formulated. These equations represent the variation of the cross section with energy, which could be used to predict the values of uncalculated cross sections.Q - value, threshold energy, binding energy, mass excess, and packing fraction for each reaction and target element have been also calculated.The evaluations are based mainly on the calculations of the optical model potential. The calculations are based on the nuclear optical potential, where the relevant parameters are collected and selected from Reference Input Parameter Library (RIPL) which is being developed under the international project coordinated by the International Atomic Energy Agency (IAEA). We study two different formula for optical model potential the first formula is the standard optical potential model and its parameters are taken from Beijing library. The second formula is the optical potential with different energy ranges. We study the ratio of the (n,f) cross sections for each Uranium isotopes relative to (n,f) cross section for U - 235 which could be considered as a standard sample. We have done the ratio not for the (n,f) cross sections only but also for other reactions like ,(n,f), (n,tot), (n,el), (n,inl), (n,2n), (n,3n), and (n,γ) relative to U - 235 reactions cross sections.Another evaluation is added to cross sections is the effect of the contamination of the daughter of U - 237 which the daughter is Np - 237 6.8day and their relative flux

دراسة تاثير المعاملة الحرارية على الخواص التركيبية والميكانيكية لبوليمر (بولي تيترافلورواثيلين) == Study the Effect of Heat Treatment on the Structural and Mechanical Properties for poly (tetrafluoroethylene

اسم المؤلف: رند باسم لطفي الكرخي
اسم المشرف: مي عبد الستار محمد نجيب
الموضوع العام: علوم الفيزياء
السنة: 2015
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: درس في هذا العمل نوعين من بولي تيترافلورواثيلين ( النقيين ولكن باختلاف الشركة المصنعة PTFE) (صيني _اماراتي ) بطريقه صب المحلول كافلام رقيقه واشرطة , بواسطه الخواص التركيبيه (حيود الاشعه السينيه ومسعريه المسح التفاضلي ) والخصائص الميكانيكية بدلاله درجات حراره مختلفة للدوره الحرارية . يبين كلا النوعين تغير في الشده المستطاره من المستوى القاعدي (100) عند تغير درجه حرارة الدورة الحرارية واظهر النوعين زيادة في التبلورية مع زياة درجة الحرارة .كذلك اختلاف في الانثالبي عند اختلاف درجات الحرارة حيث لوحظ زياة الانثالبي بزيادة درجة الحرارة واختلاف في الخصائص الميكانيكيه ( الاجهاد والانفعال عند نقطة الخضوع ونقطه الكسر ومعامل يونك) للبوليمر حيث اظهرت المعالجة الحرارية للبوليمر بدرجات حرارة مختلفة من اجل معرفة خصائصه ومقاومته الى الظروف البيئية ان الخواص الميكانيكية تزداد زيادة خطيا مع زيادة درجة الحرارة .لوحظ بان انتاج الشركه المصنعة الصينية افضل من ناحية النتائج لايجاد درجة التبلورية والخصائص الميكانيكيه عن انتاج الشركة المصنعة الاماراتية لنفس المادة البوليمرية | In this study two modifications of pure polytetrafluoroethylene (PTFE) [C2F4]n. China_UAE source prepared from solution cast as film and strip have been studied by structural (X - ray diffraction (XRD), Differential Scanning Calorimetry (DSC)) and mechanical properties .subjected to different temperature heating cycle. Both modifications show variation in the scattered X - ray intensity of the basal plane (100) as the temperature of heating cycle is changed and show increasing in crystallinity with the increase of temperature .Moreover, the Enthalpy of each kind is changed with difference of heat treatment where the enthalpy increase with the increase of temperature, and two modifications show different in mechanical properties for PTFE (young's modulus, stress at break, stress at yield, elongation at yield. And elongation at break) when the temperature is change ,The heat treatment of polymer to different temperatures in order to know its properties and resistance to environmental conditions results showed that the mechanical properties increase linearly with the increase of temperature.It seems that the product company of china is better than the product company of UAE in degree of crystallinity and mechanical properties for this polymer.

دراسة التركيب المتهيج للنوى زوجية - زوجية ذات العدد الذري Z= 50, 48, 46 في المستوى المتهيج الاول == Study of Excited Structure for Even - Even Nuclides of Z = 50, 48, 46 in The First Excited State

اسم المؤلف: رسل سعد هادي
اسم المشرف: فاطمة عبد الامير جاسم
الموضوع العام: علوم الفيزياء
السنة: 2015
الموضوع الدقيق: الفيزياء
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: درست الخواص الكهرومغناطيسية للنظائر زوجية - زوجية للنوى 48Cd , 50Sn و46Pd الغنية بالنيوترونات من خلال قوى الانتقال لرباعي القطب الكهربائي |M(E2)|2 W.u ↓ واحتمالية الانتقال المختزل B(E2)W.u ↓ لانتقال اشعة كاما من المستوى المتهيج الاول الى المستوى الارضي. حيث تم حساب قوى الانتقال لرباعي القطب الكهربائي |M(E2)|2 W.u ↓ بالاستعانة بمعدل العمر للمستوى المتهيج الاول والشدة النسبية لاشعة كاما المنبعثة من ذلك المستوى, بينما قيم احتمالية الانتقال المختزل B(E2)W.u ↓ استخرجت من خلال عمر النصف للمستوى المتهيج الاول المصحح لمعامل التحول الداخلي.وللحصول على قيمة دقيقة لانتقال رباعي القطب الكهربائي ↓ E2, تم حساب ورسم القيم المتبناة لكل من |M(E2)|2 W.u ↓ وB(E2)W.u ↓ كدالة لعدد النيوترونات.في هذا البحث, تم تحويل القيم المتبناة لانتقال ↓E2 الى قيم احتمالية الانتقال المختزل B(E2) ↑ e2b2 والتي افادتنا في دراسة تركيب النوى من حيث الاختلاف في الشكل لان عامل التشوه β تم استخراجه من B(E2) ↑ e2b2, كما ان دراسة تاثير عدد النيوترونات على سلوك كل من B(E2) ↑ e2b2 وβ في المتسلسلات الايزوتونية لنوى 48Cd , 50Sn و46Pd يعطي معلومات جيدة حول التشوه في النوى.تركزت دراستنا على ثلاث انواع مختلفة من النوى, الاول بعدد ذري سحري50 , والثاني بعدد ذري شبه سحري 48, والثالث بعدد ذري بين القشرات المغلقة 46.في نهاية العمل الحالي تم عمل مقارنة جيدة للحسابات الحالية لقيم احتمالية الانتقال المختزل B(E2) ↑ e2b2 وعامل التشوه β مع معظم القيم العملية والنظرية الحديثة. | Electromagnetic properties for even - even nuclides in neutron - rich nuclei such 50Sn, 48Cd and 46Pd have been studied through the electric quadruple transition strength |M(E2)|2 W.u ↓ and the reduced transition probability B(E2)W.u ↓for γ0 - transition from first excited state to the ground state. The electric quadruple transition strength |M(E2)|2 W.u ↓ is calculated by using life - time for excited state with the intensity of γ0 - transition, while B(E2)W.u ↓ is extracted from half - life time to state corrected for internal conversion coefficient. To obtain precise value for the transition of E2↓, the adopted value for |M(E2)|2 W.u ↓ and B(E2)W.u ↓ was calculated and plotted as a function for neutron number. In present work, the adopted values for the transition of E2↓ are converted to B(E2)exp ↑ e2b2 which helped us to study the structure for nucleus, such as the variation in shape, because the deformation parameter β is extracted from B(E2) ↑ e2b2 and the study for behavior of each of B(E2) ↑ e2b2 and β versus neutron number in isotonic chains to 50Sn, 48Cd and 46Pd gives good information about the deformation in nuclei. Our study focused on the three different types of nuclei, the first with atomic magic number 50, the second with semi - magic atomic number 48 and the third nucleus with atomic number between closed shells 46. At the end of the present work, the good comparisons for the present calculation to the values of the B(E2) ↑ e2b2 and β with most recent values of experimental and theoretical was done.
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