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Cobalt in alluvial Egyptian soils as affected by industrial activities

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Journal of Environmental Sciences 2002年第1期14卷 34-38页

作者： Ensegam A.m. Zohny (Physics Department, faculty of Science, Cairo University, Beni Swif Branch, Egypt) Physics Department Faculty of Science Cairo University Beni-Swif branch Egypt

Twenty five surface (0—20 cm) soil samples were collected from different locations in Egypt representing non polluted, moderately and highly polluted soils. The aim of this study was to evaluate total Co content in alluvial soils of Delta in Egypt using the delayed neturen activation analysis technique (DNAA). The two prominent gamma ray lines at 1173 2 and 1332 5 keV was efficiently used for 60 Co determination. Co content in non polluted soil samples ranged between 13 12 to 23 20 ppm Co with an average of 18 16±4.38 ppm. Cobalt content in moderately polluted soils ranged between 26 5 to 30 00 ppm with an average of 28 3±1.3 ppm. The highest Co levels (ranged from 36 to 64 69 ppm with an average of 51 9±9.5); were observed in soil samples collected from, either highly polluted agricultural soils due to prolonged irrigation with industrial wastewater or surface soil samples from industrial sites.

关键词： cobalt neturen activation analysis technique (DNAA) surface soil sample industrial activities

LOCAL AND GLOBAL EXPOSED POINTS

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Acta mathematica Scientia 1995年第3期15卷 335-341页

作者： m.Beltagy(mathematics Department,faculty of Science Tanta University,Egypt.) TANTA UNIV FAC SCIDEPT MATHTANTAEGYPT

In this paper we derive sufficient conditions for strict convexity of subsets in a complete simply connected smooth Riemanian manifold without focal points in terms of local and global exposed points.

关键词： exposed points strict convexity focal points.

Kinetic Study of Cementation of Copper on Zinc metal in Ethanol-Water mixtures

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Journal of materials Science & Technology 1996年第1期12卷 41-45页

作者： A.A.Zaghloul G.m.EI-Subruiti and A.m.Ahmed(Chemistry Depatment, faculty of Science, Alexandria University Alexandria, Egypt) Chemistry Department Faculty of Science Alexandria University Alexandria Egypt

The cementation reaction of copper on zinc metal in solutions of different concentrations ofcopper sulphate, at 25℃, has been studied and it is found to be a first order reaction. moreover,the rates of this reaction at 0.15 mol'L-1 copper sulphate solution have been measured in a varietyof ethanol-water media at temperatures from 20℃ to 40℃. The correlation between the masstransfer coefficient and the dielectric constant has been investigated. Also, the thermodynamicparameters of activation have been calculated. The isokinetic relationship reveals the existenceof compensation effect, where the solute-solvent interactions play an important role.

关键词： Figure Kinetic Study of Cementation of Copper on Zinc metal in Ethanol-Water mixtures

NUmERICAL AND EXPERImENTAL INVESTIGATION OF BEVELED TRAILING EDGE FLOW FIELDS

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Journal of Hydrodynamics 2008年第3期20卷 273-279页

作者： mOSALLEm m.m. Department of mechanical Power Engineering and Energy Faculty of EngineeringMinia University

The characteristics of flow past beveled trailing edges attached to flat plates have been investigated numerically and experimentally. The test models used in the present study were two 2D blunt-faced flat plates having asymmetric beveled trailing edges of angles 27° and 60°. The numerical simulation results display an asymmetric wake behind the 27° beveled trailing edge and von karmen street vortices behind the 60° beveled trailing edge. The flow visualization using cavitation technique showed the same observations of the numerical simulation. Therefore, it is obvious that the trailing edge geometry has a pronounced effect on the wake development and vortex shedding. Also, it is concluded that the cavitation phenomenon can be used as a visualization technique at high flow velocities.

关键词： cavitation technique visualization beveled trailing edge vortex shedding

Atom–field entanglement in the Jaynes Cummings model without rotating wave approximation

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Chinese Physics B 2015年第4期24卷 70-75页

作者： m.mirzaee m.Batavani Department of Physics Faculty of Science Arak University

In this paper, we present a structure for obtaining the exact eigenfunctions and eigenvalues of the Jaynes-Cummings model （JCm） without the rotating wave approximation （RWA）. We study the evolution of the system in the strong coupling region using the time evolution operator without RWA. The entanglement of the system without RWA is investigated using the Von Neumann entropy as an entanglement measure. It is interesting that in the weak coupling regime, the population of the atomic levels and Von Neumann entropy without RWA model shows a good agreement with the RWA whereas in strong coupling domain, the results of these two models are quite different.

关键词： atom-photon interaction Jaynes--Cummings model quantum entanglement

Insights from an academic endeavor into central nervous system drug discovery

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Neural Regeneration Research 2025年第6期20卷 1717-1718页

作者： Lieve van Veggel An m.Voets Tim Vanmierlo Rudy Schreiber BIOmED Biomedical Research Institute Faculty of Medicine and Life SciencesHasselt UniversityHasseltBelgium Department of Psychiatry and Neuropsychology Division of Translational NeuroscienceEuropean Graduate School of NeuroscienceSchool for Mental Health and NeuroscienceMaastricht UniversityMaastrichtThe Netherlands Section of Psychopharmacology Neuropsychology and PsychopharmacologyFaculty of Psychology and NeuroscienceMaastricht UniversityMaastrichtThe Netherlands University mS Center(UmSC) Hasselt-PeltBelgium

Historically,"big pharma"did most central nervous system drug discovery R&D ***,in modern times their"management reductionism"resulted in disappointing pipelines and pharma resided to(late)development,regulatory approval,and marketing(Thong,2015).This had significant consequences for financing and executing research,resulting in a larger role for funding by governments and patient-organizations and a shift of research to academia(mazzucato,2013).

关键词： academic approval consequences

NO Level and Endothelial NO Synthase Gene Polymorphism (Glu298Asp) in the Patients with Coronary Artery Disease from the Turkish Population

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Acta Biochimica et Biophysica Sinica 2004年第10期36卷 661-666页

作者： Lale AFRASYAPDepartment of Biochemistry, faculty of Health, mugla University, mugla, Turkey ,Guler OZTURK Department of Physiology faculty of m.dicine maltepe University maltepe-Istanbul Turkey

Nitric oxide is synthesized from L-arginine by endothelial nitric oxide synthase encoded by eNOS gene. This study was performed to investigate the relationship between the serum nitric oxide level and eNOS gene polymorphism in the Turkish population with angiographically diagnosed coronary artery disease (63.47 ± 9.10 years old, n=250) and control subjects without any history and/or risk factors of coronary artery disease (60.71 ± 9.14 years old, n=150). Griess assay and PCR-RFLP analysis were used to measure the serum nitric oxide metabolites and genotypes, respectively. It was found that Glu/Glu, Glu/Asp and Asp/ Asp genotype frequencies of the eNOS were 49.3%, 41.3% and 9.3% respectively in the control group, and 45.6%, 41.2% and 13.2% in the patient group. Serum nitric oxide levels were (32.56 ± 17.26) μm in controls and (29.84 ± 11.88) μm in patients. Neither the frequencies of the Glu298Asp genotypes nor the serum nitric oxide levels showed a significant difference between the groups. There was also no correlation between serum nitric oxide levels and the frequencies of the eNOS genotypes. Result showed that the coronary artery disease of the Turkish population seemed to develop without any alterations in eNOS Glu298Asp genotype frequency and the serum nitric oxide level.

关键词： coronary artery disease genetics nitric oxide polymorphism population

EPR of Irradiation Induced Centers in Some Vitreousmatrices Containing Copper

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Journal of materials Science & Technology 1995年第4期11卷 299-303页

作者： m.Peteanu L.Cociu and I.Ardelean (faculty of Physics, Babes-Bolyai University, 3400 Cluj-Napoca, Romania) Babes-Bolyai Univ Cluj-Napoca Romania

Boro-germanate glasses containing copper, i.e., xCuO(1-x)[GeO2·B2O3] subjected to gamma irradiation, were studied by means of EPR. Comparisons were made with the xCuO·(1-x)[Na2B4O7] system. Irradiation induced centers were detected. These are: electron trapped at a hydrogen compensated germanium ion centers; boron oxygen hole centers and electron trapped at an oxygen vacancy centers. Strong dependence of the paramagnetic irradiation-induced centers concentration on the CuO content of the sample was evidenced.

关键词： EPR of Irradiation Induced Centers in Some Vitreousmatrices Containing Copper

Kinetics and Thermodynamic Parameters of the CopperExchange on Na-montmorillonite Clay mineral inSelected Solvents

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Journal of materials Science & Technology 1995年第4期11卷 265-268页

作者： A.A.Zaghlou m.EI-Batouty and Sh.A.Shazly (Chemistry Dept., faculty of Science, Alexandria University, Alexandria, Egypt) Alexandria Univ Alexandria Egypt

The kinetics of Cu ion exchange on Na-montmorillonite clay mineral has been investigated at three temperatures, in three solvents: H2O, ethylene glycol and glycerol. Solvent effects on the reaction rate have been discussed. The thermodynamic activation parameters were calculated and discussed in terms of solvation effects. The determined isokinetic temperature indicates that the reaction is enthalpy controlled where the interaction between solvent and clay surface plays an important role. A reaction mechanism which describes the solvent effect on the rate of Cu ion exchange is proposed.

关键词： Na Kinetics and Thermodynamic Parameters of the CopperExchange on Na-montmorillonite Clay mineral inSelected Solvents