The ceramic compound Mg1-xSixAl2O4 (x= 0, 0.1, 0.2, 0.3, 0.4) was prepared from nano powder of Al2O3 and MgO doped with Nano powder of SiO2 at different molar ratios. The specimens were prepared by standard chemical solid reaction technique and sintered at 1450 oC. Structure of the specimens was analyzed by using X-ray diffraction (XRD). The X-ray patterns of the specimens showed the formation of pure simple cubic spinel structure MgAl2O4 phase with space group of ̅ . The average grain size and surface topology were studied by atomic force microscopy. The results showed that the average grain size was about 73-90 nm. The DC electrical properties of the specimen were measured. The apparent density was found to increase and the porosity and water absorption were found to decrease with increase of Si addition. Mechanical properties were characterized by Vicker’s micro hardness and Brazilian fracture test to measure the fracture toughness of the samples. The micro hardness decreased with Si addition increase. Fracture toughness increased with the increase in Si addition.
In this study light elements 10B , 10Be for 10B(n,p)10Be reaction as well as proton energy from 0.987 MeV to 2.028 MeV with threshold energy (1.04MeV) are used according to the available data of reaction cross sections. The more recent cross sections data of 10Be(p,n)10B reaction is reproduced in fin steps in the specified energy range , as well as cross section (p,n) values were derived from the published data of (n,p) as a function of energy in the same fine energy steps by using the reciprocity theory of principle inverse reaction . This calculation involves only the first excited state of 10B , 10Be in the reactions 10Be(p,n)10B and 10B(n,p)10Be.
RESRAD is a computer model designed to estimate risks and radiation doses from residual radioactive materials in soil. Thirty seven soil samples were collected from the area around the berms of Al-Tuwaitha site and two samples as background taken from an area about 3 km north of the site. The samples were measured by gamma-ray spectrometry system using high purity germanium (HPGe) detector. The results of samples measurements showed that three contaminated area with 238U and 235U found in the study area. Two scenarios were applied for each contaminated area to estimate the dose using RESRAD (onsite) version 7.0 code. The total dose of resident farmer scenario for area A, B and C are 0.854, 0.033 and 2.15×10-3 mSv.yr-1, respectively. Whi
... Show MoreThe aim of this research is to estimate the area unit function of productivity for the potato crop in Anbar province for the autumn season (2008 / 2009) Anbar province has been chosen as an applied model for the study due to its well known in cultivating potato crop , and the data were collected through a random sample about (10%) from the study society with a (150) farmers, The results indicated that the double logarithmic formula was the best representative of the relationship between crop productivity and independent variables (quantity of potato tubers , quantity of herbicides stuffs, quantity of fertilizer , hours of mechanical labour
... Show MoreThe imposition of (state) policy on the South Kuril Islands.In the Pacific was a subject
of borders dispute between Japan and Soviet Union which appeared clearly afterthe second
Great War and during the cold war. Despite the end of the Cold War and the collapse of the
Soviet Union in 1991, this conflict has continued, thus both countries had to made a historic
and legitimate claims to demand the rights of sovereignty and ownership of four islands
occupied by the Soviet Union after World War II under the international conventions and
treaties, but these claims are proven failures through the continuation of the regional conflict.
At the beginning of 1935 theMinistry of (Yasin AL-Hashimi) was formed which was the result of the (Sulayikh)Conference .The new ministys policy was towards the authority of the one party and the exclusivity of power.The policy of (Yasin AL-Hashemi)has faced severe campaigns from the AL-Ekhaa and AL-Ahaly newspapers.The new ministry like its predecessor ministries . When it faces criticism from opposition newspapers .its shutting down newspapers and not accepting requests for them. Some opposition newspapers named Yassin AL-Hashemi (the dictator).Iraqi opposition newspapers have been neglected and deprived of press freedom although they were the main factor in educating the community and representing the public opinion of people . Lt appe
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The current research variables have received increasing attention in the recent period because they are one of the important issues affecting the future of organizations, as a result of the speed of environmental variables that have greatly affected organizations and for the purpose of explaining the relationships and links between research variables, as this research presents a test "the type and direction of the relationship between strategic foresight capabilities As an independent variable and green creativity "as a respondent variable. A set of questions has arisen about the basic research problem, including what is the nature and level of interest in the research variables (strategic foresight capabilities an
... Show MoreThe present paper stresses the direct effect of the situational dimension termed as “reality” on the authors’ thoughts and attitudes. Every text is placed within a particular situation which has to be correctly identified by the translator as the first and the most important step for a good translation. Hence, the content of any word production reflects some part of reality. Comprehending any text includes comprehending the reality’s different dimensions as reflected in the text and, thus illuminating the connection of reality features.
Аннотация
Исследование под названием ((«Понимание реальности» средство полно
... Show MoreThis study has been performed to study the inhibitory effects of crude plant extracts of Bay (laurus nobilis) leaves against some bacterial isolates represented by Staphylococcus aureus, Staphylococcus epidermids, Proteus vulgaris, Bacillus subtilis, Escherichia coli, and Pseudomonas aeroginosa in vitro. The results showed that percentages of essential chemical of laurus nobilis leaves which represented by moisture, total oil, total ash, crude protein, crude fibers, carbohydrites and caloric values in dry weight are 5.96, 4.28, 14.2, 8.75, 24.8, 76.99%, and 284.92 kcal/100g respectively, the percentages of some major and minor mineral elements of laurus nobilis leaves powder which represented by Mg, Fe, Cu, Pb, Cd and As, are: 0.211, 0.1
... Show MoreThis study is a numerical analysis of the transition process from the second to the third mode in transformer oil. In this study, it was determined how to change from the second to the third mode, which is thought to be a precursor to the process of electrical breakdown, which results in a significant loss of electrical energy and harm to electrical devices and equipment. The initiation time, length, rate of propagation velocity, and radius of the streamer discharge were determined. The transition from the second to the third mode during the electrical discharge process may lead to the occurrence of an electrical breakdown, which is one of the greatest challenges facing scientists and engineers who deal with the
... Show MoreWheat straw was modified with malonic acid in order to get low cost adsorbent have a good ability to remove copper and ferric ions from aqueous solutions, chemical modification temperature was 120°C and the time was 12 h. Parameters that affect the adsorption experiments were studied and found the optimum pH were 6 and 5 for copper and iron respectively and the time interval was 120 min and the adsorbent mass was 0.1 g. The values for adsorption isotherms parameters were determined according to Langmuir [qmax were 54.64 and 61.7 mg/g while b values were 0.234 and 0.22 mg/l] , Freundlich [Kf were 16.07 and 18.89 mg/g and n were 2.77 and 3.16], Temkin [B were 0.063 and 0.074 j/mol and At were 0.143 and 1.658 l/g] and for Dubinin-Radushkev
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