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Calculating the thermal properties of 93,94,95Mo using the BCS model with an average value gap parameter

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Nuclear Science and Techniques 2017年第9期28卷 81-86页

作者： V. Dehghani Gh. Forozani kh. Benam Physics Department Faculty of Sciences University of Sistan and Baluchestan Zahedan Iran Physics Department Bu-Ali Sina University Hamedan Iran

The gap parameter of the standard BCS model is replaced by the order parameter of the modified Ginzburg–Landau theory. Using this new form of the BCS model, the energy, entropy, and heat capacity of ^(93,94,95)Mo nuclei are calculated. The results are compared with the experimental data and standard BCS results. Since the order parameter does not drop to zero at a critical temperature, our results for thermal properties are free of singularities. We have shown that the heat capacity as a function of temperature behaves smoothly and it is highly in agreement with the experimental heat capacity, while heat capacity behaves singularly and discontinuously in the standard BCS model.A smooth peak in the heat capacity is observed which is interpreted as a signature of the transition from the superfluid to the normal phase.

关键词： BCS模型模型参数计算热性能平均值金兹堡-朗道理论差距实验数据

Synthesis of thiopyrano[4″,3″:4′,5′]pyrido[3′,2′:4,5]furo[3,2-d]pyrimidines

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Chinese Chemical Letters 2010年第6期21卷 669-673页

作者： Essam kh. Ahmed Mohamed A. Ameen Chemistry Department Faculty of ScienceEl Minia UniversityEl Minia 61519Egypt

Reactions of the 6-hydroxy-thiopyrano[3,4-c]pyridine-5-carbonitrile derivative 1 withα-halo-carbonyl compounds gave the ortho-substituted intermediates 2a-c which were converted into furo[2,3-b]thiopyrano[4,3-d]pyridines 3a-c by fusion of a furan moiety under basic *** cyclization of 3a-c led to a fusion of a pyrimidine ring,yielding the tetracyclic products 6,7 and *** addition,condensation of 6 with various aromatic aldehydes afforded the corresponding imines 9a,*** reaction of 7 gave products 10a,b.

关键词： S N-Heterocycles S N O-Heterocyles Furo[2 3-b]thiopyrano[4 3-d]pyridine Thiopyranopyridofuropyrimidines

It is Time for a Change： oPetri Dishes Weaken Cells

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Journal of Bionic Engineering 2012年第3期9卷 353-357页

作者： Andrei P. Sommer Mike kh. Haddad Hans-Joerg Fecht Institute of Micro and Nanomaterials University of Ulm 89081 Ulm Germany Institute for Nanotechnology Karlsruhe Institute for Technology 76344 Eggenstein-Leopoldshafen Germany

We wish to draw the attention to a potential deficiency in the biocompatibility of polystyrene cell culture dishes which is caused by a softening of the material under relevant culture conditions. The finding confirms the central hypothesis of our previous model study. In it we assumed a local increase in pH at the interface between the hydrophilic polymer and liquid. The finding is of considerable biological interest. Polystyrene tissue culture dishes are now in use for 50 years. To the best of our knowledge their biocompatibility has never been challenged. Here we report the first experimental proof that exposure to water softens the surface of polystyrene Petri dishes. We expect that our results will stimulate the development of a new generation of cell culture devices, including Petri dishes and culture flasks, and the establishment of improved biomimetic settings for tissue engineering and stem cell research. New non-swelling biomaterials or nanocoatings designed to reduce the swelling of polymer ct, lture dishes could improve cell performance. The need for further study is clear.

关键词： Petri dish polystyrene biomimetic triangle nanoindentation stem cells diamond

Electrical Characteristics of A1/CNT/NiPc/PEPC/Ag Surface-Type Cell

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Chinese Physics Letters 2010年第10期27卷 164-167页

作者： Mutabar Shah kh. S. Karimov Zubair Ahmad M. H. Sayyad Ghulam Ishaq kh.n Institute of Engineering Sciences and Technology Topi-23640 Swabi N.W.F.P Pakistan Physical Technical Institute of Academy of Sciences Rudaki Ave.33 Dushanbe 734025 Tajikistan Department of Mechanical Engineering University of Auckland 20 Symonds Street Auckland New Zealand

The blend of nickel phthalocyanine （NiPc）（2 wt. %） poly-N-epoxypropylcarbazole （PEPC）, （1 wt. %） and carbon nano-tube （CNT） powder （2 wt. %） in benzole is deposited by drop-casting on glass substrates with pre-deposited metallic electrodes to fabricate Ag/CNT/NiPc/PEPC/A1 surface type cell. It is assumed that the high nonlinearity of the I — V characteristics is related to deep traps in the nano-scale depletion region in NiPc that is observed experimentally. The values of ideality factor and barrier height are determined from the I — V curve and they are found to be 8.4 and 1.05eV, respectively. The values of mobility and conductivity are calculated to be 7.94 × 10？8 cm/Vs and 3.5 × 10？6 Ω？1 cm？1. The values of ideality factor and series resistance are also calculated by using Cheung＇s functions, which are in good agreement with the values calculated from the I — V curve.

关键词： Elderly Silver Aging Lymphocytes Curium Computers

Influence of monovalent cations and CuO nanoparticles on X-nanozeolite in uranium anionic species separation from contaminated drinking water

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Chinese Journal of Chemical Engineering 2017年第6期25卷 782-792页

作者： H.R. Shakur kh. Rezaee Ebrahim Saraee M.R. Abdi G. Azimi Department of Nuclear Engineering Faculty of Advance Sciences and Technologies University of lsfahan Isfahan 81746-73441 lran Department of Physics Faculty of science University of lsfahan lsfahan 81747-73441 Iran Department of Chemistry University of lsfahan lsfahan 81747-73441 Iran

The main purpose of this work was the modification of NaX nanozeolite using copper oxide nanoparticles and various monovalent cations such as K^+, Cs^+, and Ag^+in order to make the negatively charged zeolite surface accessible for anionic forms of uranium which are the most dominant species of uranium in the contaminated radioactive waters at natural p H. Various methods such as the X-ray fluorescence(XRF), X-ray powder diffraction(XRD), field emission scanning electron microscopy(FE-SEM), transmission electron microscopy(TEM), Fourier transform infrared spectroscopy(FT-IR), and atomic absorption spectroscopy(AAS) were used to characterize the final synthesized absorbents. Batch technique was used to study the adsorption behavior of uranium ions from polluted drinking water by Na X nanozeolite and its modified forms. In order to better understand the performance of them, the results were compared with those that were obtained for synthesizing bulk NaX zeolite and Na-form of clinoptilolite natural zeolite. Preliminary results indicated that uranium sorption increased as the loading level of CuO nanoparticles on NaX nanozeolite increased from 2.1 wt% to 11.2 wt%. In addition,from the obtained data, an increase in uranium removal efficiency resulted as charge/ionic radius ratio of exchanged cation decreased. Also, the effect of contact time, solid–liquid ratio, initial concentration and temperature on the adsorption process was studied. It is worth mentioning that, in this study, the sorption of uranium was performed under natural conditions of pH and the presence of competing cations and anions which are available in drinking waters.

关键词： Zeolite Monovalent cation NaX/CuO nanocomposite Uranium anions Separation Waste water

PARTICULATE SUSPENSION FLOW INDUCED BY SINUSOIDAL PERISTALTIC WAVES THROUGH ECCENTRIC CYLINDERS： THREAD ANNULAR

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International Journal of Biomathematics 2013年第4期6卷 113-137页

作者： kh. S. MEkh.IMER Y. ABD ELMABOUD A. I. ABDELLATEEF Mathematics Department Faculty of Science Al-Azhar University Nasr City 11448 Cairo Egypt Mathematics Department Faculty of Science Tail University Hawia (888) Tail Saudi Arabia Mathematics Department Faculty of Science and Arts Khulais King Abdulaziz University (KAU) Saudi Arabia Mathematics Department Faculty of Science Al-Azhar University (Assiut Branch) Assiut Egypt Basic Science Department Higher Institute of Engineering Shorouk City Cairo Egypt

This paper describes a new model for obtaining analytical solutions of peristaltic flow through eccentric annuli. A mathematical model of peristaltic pumping of a fluid mixture （as blood model） in a circular eccentric cylinders is presented and it is motivated due to the fact that thread injection is a promising method for placing medical implants within the human body with minimum surgical trauma. For the eccentric annuli, the inner cylinder is rigid and moving with a constant velocity V, and the outer one is hollow flexible cylinder that has a sinusoidal wave traveling down its wall. The coupled differential equations for both the fluid and the particle phases have been solved by using two methods and the expressions for the velocity distribution of fluid and particle phase, flow rate, pressure drop, friction forces at the inner and outer cylinders have been derived. The results obtained are discussed in brief. The significance of the particle concentration and the eccentricity parameter as well as the nature of the basic flow has been well explained.

关键词： Eccentric annulus flows particle fluid suspension peristalsis endoscope

Low temperature properties of organicinorganic Ag/p-CuPc/n-GaAs/Ag photoelectric sensor

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Science China(Technological Sciences) 2008年第2期51卷 153-161页

作者： kh. S. KARIMOV I. QAZI T. A. kh.N M. I. FEDOROV Physical Technical Institute of Academy of Sciences GIK Institute of Engineering Science and Technology State Technical University

A thin organic film of p-type semiconducting copper phthalocynanine (CuPc) was deposited by vacuum evaporation on an n-type GaAs single-crystal semiconductor substrate. The fabricated Ag/p-CuPc/n-GaAs/Ag sensor was carried through an ageing process to stabilize the parameters. Voltage-current characteristics and photoelectrical response of the sensor were investigated at a wide temperature range of 82 to 350 K. Photoelectric characteristics were measured under non-modulated filament-lamp illumination. It was observed that such sensor parameters as rectification ratio,threshold voltage,junction,shunt and series resistances,open-circuit voltage and short circuit current are temperature-dependent. It was found that wide-range voltage-current characteristics of the sensor may be de-scribed similarly to that of a Schottky barrier diode. Using the experimental data on voltage-current characteristics and absorbance of the CuPc films,the energy-band diagram of the p-CuPc/n-GaAs heterojunction was developed. It was shown that data obtained from simulation of an equivalent circuit of photoelectric sensor agreed with experimental results.

关键词： organic solar cell organic-inorganic heterojunction temperature dependent I-V characteristics

The Impact of Energy Produced by Civilization on Global Warming

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Open Journal of Ecology 2022年第6期12卷 325-332页

作者： Vladimir kh. Dobruskin Independent Researcher Beer Yacov Israel

The thermodynamic approach to the evolution of human society shows that the energy generated by civilization disrupts the thermal balance of the Earth. This energy did not exist before the advent of civilization;it practically does not affect the thermal radiation of the planet and dissipates in the atmosphere in the form of heat, increasing the kinetic energy of gas molecules and, consequently, their temperature. Since air molecules cannot leave the Earth due to gravity, excess heat accumulates on the planet and contributes to global warming. A quantitative assessment of the effect is given. An analogy can be made: the energy generated by humanity heats the atmosphere, as a furnace heats a dwelling.

关键词： Thermodynamics Global Warming Energy of Civilization Climate

Simulation of Dose Assessment for Special Environmental Radioactivity Distribution Using Monte Carlo Technique

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Open Journal of Modelling and Simulation 2014年第3期2卷 91-96页

作者： kh. Allam Nuclear Law department Nuclear and Radiological Regulatory Authority (NRRA) Cairo Egypt

Many researchers use the estimation method of exposure doses due to natural radioactivity adopted by UNSCEAR equation, which is based on an infinite plan source modeling. The results in most cases are acceptable within acceptable accuracy and error. However, in many cases, this approach cannot be applied e.g., for more complicated source geometry, composition, radioactivity distribution and so on. In previous situations, simulation and modeling are needed for exposure dose calculation to get more acceptable and accurate results. In the present work, modeling and recalculation of exposure dose rate are performed for an important previous published study about Hammam Pharaon. The study is selected because of its special physical characterization parameters and possible effects on Egyptian tourism. The effects of radionuclides distribution with soils and source composition, density, and geometry as recommended by NCRP 129 have been taken into consideration. The results for depth profile calculation show the conformation with the NCRP 129, which indicates a reduction in the free air exposure dose due to the fact that the above soil covered the active slab by 20% - 25% for 1 cm cover-up to 95% - 100% for 30 cm cover. In addition, the effect of density variation in dose rate is studied. A comparison with previous results has been performed.

关键词： Dose Rate Calculation Monte Carlo Simulation Environmental Radioactivity