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Ion-Acoustic Rogue Waves in multi-ion Plasmas

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Communications in Theoretical Physics 2019年第8期71卷 1017-1023页

作者： m.hassan m.H.Rahman N.A.Chowdhury A.mannan A.A.mamun Department of Physics Jahangirnagar University Savar Dhaka-1342 Bangladesh Wazed miah Science Research Center Jahangirnagar University Savar Dhaka-1342 Bangladesh Institut fur mathematik Martin Luther Universitat Halle-Wittenberg Halle Germany

The basic properties of nonlinear ion-acoustic(IA) waves(IAWs), particularly finite amplitude IA rogue waves(IARWs) in a plasma medium(containing pair ions, iso-thermal positrons, and non-thermal electrons) are theoretically investigated by deriving the nonlinear Schr¨odinger equation(NLSE).The criteria for the modulational instability of IAWs, and the basic features of finite amplitude IARWs are *** modulationally stable and unstable regions are determined by the sign of the ratio of the dispersive coefficient to the nonlinear coefficient of *** latter is analyzed to obtain the region for the existence of the IARWs, which corresponds to the unstable *** shape of the profile of the rogue waves depends on the non-thermal parameter α and the ratio of electron temperature to positron *** is found that the increase in the value of the non-thermal parameter enhances both the amplitude and width of IARWs, and that the enhancement of electron(positron) temperature reduces(enhances) the amplitude and width of *** is worth to mention that our present investigation may be useful for understanding the salient features of IARWs in space(viz., upper region of Titan’s atmosphere, cometary comae, and Earth’s ionosphere, etc.)and laboratory(viz., plasma processing reactor and neutral beam sources, etc.) plasmas.

关键词： pair ions modulational instability rogue waves

Liver stiffness as a predictor of hepatocellular carcinoma behavior in patients with hepatitis C related liver cirrhosis

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Hepatobiliary & Pancreatic Diseases International 2020年第1期19卷 22-28页

作者： Sameh A Lashen mohamed m Elshafei Fahmy H Hablass Eman A Alsayed Asmaa A hassan Department of Internal medicine Faculty of MedicineUniversity of AlexandriaAlexandriaEgypt Department of Radiology Faculty of MedicineUniversity of AlexandriaAlexandriaEgypt Department of Biomedical Informatics and medical Statistics Medical Research InstituteUniversity of AlexandriaAlexandriaEgypt

Background: Risk strati cation and prognostication of hepatocellular carcinoma (HCC) help to improve patient outcome. Herein we investigated the role of liver stiffness measurement (LSm) in the prediction of HCC behavior. methods: Totally 121 na ve patients with HCC were included. HCC radiological evaluation and staging were done. LSm was measured using virtual touch quanti cation. Patients were divided into early to intermediate HCC (BCLC-0, A and B) and late HCC (BCLCC and D). HCC was treated according to the BCLC stage. HCC recurrence-free interval was estimated. Results: The mean LSm inside the tumor was signi cantly lower than the peri-tumoral area and the cirrhotic non-cancerous liver parts (Pmean LSm inside the tumor and in the peri-tumoral tissue was lower than the corresponding values in the early to intermediate HCCs stage (Pm inside the tumor and in the peri-tumoral tissue negatively correlated with serum AFP, tumor vascular invasion, and stage (Pm inside the tumor and inversely to LSm in cirrhotic non tumorous liver part. Kaplan-meier analysis showed that the recurrence-free interval was signi cantly longer in patients with LSm inside the tumor of ≥1.25m/s compared to those with LSm inside the tumor ofm/s. Conclusions: LSm can serve as a potential non-invasive predictor for HCC clinical behavior and the recurrence-free interval following loco-regional treatments.

关键词： Fibrosis Hepatitis C Hepatocellular carcinoma Point shear wave Liver cirrhosis

metal Contamination in Nullah Dek Water and Accumulation in Rice

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Pedosphere 2007年第1期17卷 130-136页

作者： m.SARFRAZ S.m.mEHDI G.hassan S.T.ABBAS Plant Nutrition Division Soil Salinity Research InstitutePindi Bhattian(Pakistan) Crop Sciences Institute National Agricultural Research Centre(NARC)Islamabad (Pakistan)

A research study was carried out to determine the electrical conductivity （EC）, residual sodium carbonate （RSC）, sodium adsorption ratio （SAR）, pH and metals in metal-polluted irrigation water from a nullah and those in soils over a period of time, and the effect of metals on rice yield and metal concentrations in rice grain and straw. Two sites （I and If） were selected on the bank of Nullah Dek at Thatta Wasiran in Sheikhupura District （Pakistan）, with two rice varieties, Super Basmati and Basmati 385, at both sites. Water samples were collected during rice crop growth at 15-day intervals from August 3 to November 1, 2002. The results showed that Nullah Dek water had an EC 〉1.0 dS m^-1 and RSC of 2.78-4.11 mmolc L^-1, which was hazardous for crops, but the SAR was within the safe limit. Cu, mn Cd and Sr were also within safe limits. The soil analysis showed that Site Ⅱ was free from salinity/sodicity, whereas Site Ⅰ was saline sodic. Among metals, Zn was sometimes deficient, Cu, mn and Fe were adequate, and St, Ni and Cd were within safe limits in the soil at both the sites. After the rice crop harvest, concentrations of all metals tested were usually slightly increased, being higher in the upper soil layer than the lower. In addition, Basmati 385 produced higher rice grain and straw yield than Super Basmati. Chemical analysis of rice grain indicated the presence of Zn, Cu, Fe, mn, Pb and Sr, whereas rice straw contained Zn, Cu, Fe, mn and Sr, with Cd and Ni both being found in minute quantities.

关键词： contaminated water metal accumulation rice salinity and sodicity

Local Energy Dissipation/Transition in Field Effect molecular Nanoelectronic Systems:a Quantum mechanical methodology

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Communications in Theoretical Physics 2019年第4期71卷 441-454页

作者： Reza Safari hassan Sabzyan Department of Chemistry Faculty of Science University of Qom Department of Chemistry University of Isfahan

Electronic and vibrational intra-molecular thermoelectric-like ?gures of merit(ZT_γ~m) are introduced for single molecule nanoelectronic system, using quantum theory of atoms in molecule. These ?gures of merit are used to describe intra-molecular or local energy dissipation/transition(as in Joule-like, Peltier-like, and Thomson-like effects) in?eld effect molecular devices. The ZT_γ~m?gures of merit are computed for two proposed molecular devices. Analysis of the results shows that ZT_γ~mdepends almost non-linearly on the electric ?eld(EF) strength. Also, the intra-molecular Joule-like heating plays a dominant role in the local energy dissipation, and intra-molecular Thomson-like heating is generally larger than the intra-molecular Peltier-like heating. Introduction of ZT_γ~mcan be applied to extend the analysis of thermoelectric heating down to molecular and intra-molecular levels, and thus can be used to predict characteristics and performance of any candidate multi-terminal or multi-pole molecular systems prior to their application in real nanoelectronic circuits.

关键词： intra-molecularheattransfer local energy dissipation fieldeffect molecular device nanoelectronic devices QTAIm

A Novel Investigation on Using Strain in Barriers of 1.3 μm AlGaInAs-InP Uncooled multiple Quantum Well Lasers

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Communications in Theoretical Physics 2010年第9期54卷 529-535页

作者： Vahid BahramiYekta hassan Kaatuzian Photonics Research Laboratory(P.R.L) Department of Electrical EngineeringAmirkabir University of Technology

In this study we investigate strain effect in barriers of 1.3 μm AlCalnAs-InP uncooled multiple quantum well lasers. Single effective mass and Kohn-Luttinger Harniltonian equations have been solved to obtain quantum states and envelope wave functions in the structure. In the case of unstrained barriers, our simulations results have good agreement with a real device fabricated and presented in one of the references. Our main work is proposal of 0.2% compressive strain in the structure Barriers that causes significant reduction in Leakage current density and Auger current density characteristics in 85 ℃. 20% improvement in mode gain-current density characteristic is also obtained in 85 ℃.

关键词： multiple quantum well laser semiconductor laser strain in barrier uncooled

Robust Switch Selection in Radial Distribution Systems Using Combinatorial Optimization

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CSEE Journal of Power and Energy Systems 2022年第3期8卷 933-940页

作者： Hani mavalizadeh Omid Homaee Reza Dashti Josep m.Guerrero hassan Haes Alhelou Pierluigi Siano Fanavaran moj Khatam Tehran 16844Iran School of Electrical Engineering Iran University of Science and TechnologyTehran 16844Iran School of Advanced Technologies Iran University of Science and TechnologyTehran 16844Iran Department of Energy Technology Aalborg UniversityAalborg 9220Denmark Department of Electrical Power Engineering Faculty of Mechanical and Electrical EngineeringTishreen UniversityLattakia 2230Syria Department of management&Innovation Systems University of SalernoFisciano 84084Italy

Selecting the best type of equipment among available switches with different prices and reliability levels is a significant challenge in distribution system *** this paper,the optimal type of switches in a radial distribution system is selected by considering the total cost and reliability criterion and using the weighted augmented epsilon constraint method and combinatorial optimization.A new index is calculated to assess the robustness of each Pareto ***,for each failure,repair time is considered based on historical *** Carlo simulations are used to consider the switch failure uncertainty and fault repair time uncertainty in the *** proposed framework is applied to an RTBS Bus-2 test ***,the model is also applied to an industrial system to verify the proposed method’s excellent performance in larger practical engineering problems.

关键词： Combinatorial optimization monte Carlo Simulation multi-objective optimization radial distribution system reliability robustness

Rapid sequence induction(RSI) in trauma patients: Insights from healthcare providers

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World Journal of Emergency medicine 2019年第1期10卷 19-26页

作者： Bianca m.Wahlen Ayman El-menyar mohammad Asim hassan Al-Thani Department of Anesthesia Hamad General Hospital Clinical Research Trauma & Vascular Surgery Hamad General Hospital Clinical medicine Weill Cornell Medical College Department of Surgery Trauma Surgery Hamad General Hospital

BACKGROUND: We aimed to describe the current practice of emergency physicians and anaesthesiologists in the selection of drugs for rapid-sequence induction(RSI) among trauma ***: A prospective survey audit was conducted based on a self-administered questionnaire among two intubating specialties. The preferred type and dose of hypnotics, opioids, and muscle relaxants used for RSI in trauma patients were sought in the questionnaire. Data were compared for the use of induction agent, opioid use and muscle relaxant among stable and unstable trauma patients by the intubating ***: A total of 102 participants were included; 47 were anaesthetists and 55 were emergency physicians. Propofol(74.5%) and Etomidate(50.0%) were the most frequently used induction agents. Significantly higher proportion of anesthesiologist used Propofol whereas, Etomidate was commonly used by emergency physicians in stable patients(P=0.001). Emergency physicians preferred Etomidate(63.6%) and Ketamine(20.0%) in unstable patients. The two groups were comparable for opioid use for stable patients. In unstable patients, use of opioid differed significantly by intubating specialties. The relation between rocuronium and suxamethonium use did change among the anaesthetists. Emergency physicians used more suxamethonium(55.6% vs. 27.7%, P=0.01) in stable as well as unstable(43.4 % vs. 27.7%, P=0.08) ***: There is variability in the use of drugs for RSI in trauma patients amongst emergency physicians and anaesthesiologists. There is a need to develop an RSI protocol using standardized types and dose of these agents to deliver an effective airway management for trauma patients.

关键词： Rapid-sequence induction Trauma Emergency physicians Anaesthetists Drugs

Synthesis of a New Class of Highly Functionalized Phosphorus Ylides Containing Heterocyclic Compounds

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Chinese Journal of Chemistry 2012年第8期30卷 1893-1900页

作者： Shaabani Ahmad Keshipour Sajjad Aghaei morteza Khodabandeh m. hassan Zahedi mansour Department of Chemistry Shahid Beheshti University G. C. P. O. Box 19396-4716 Tehran Iran

The zwitterionic intermediate generated from the reaction of triphenylphosphine with electron deficient acety- lenic compounds was trapped by various NH acids. The synthesis resulted in a new class of highly functionalized heterocyclic compounds. Some of the reactions produced E and Z isomers. And the stability and transformation of them were studied by dynamic 1H NmR and density functional theory （DFT） calculations.

关键词： highly functionalized heterocyclic compounds phosphorus ylides triphenylphosphine DFT dynamic 1H NmR

Elemental analysis of some Egyptian ores and industrial iron samples by neutron activation analysis

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Journal of Environmental Sciences 2001年第1期13卷 115-118页

作者： A.Srror N.Abdel Basset A.S.Abdel Haleem A.m.hassan Nuclear Physics Lab. Physics DepartmentFaculty of GirlsAin Shams UniversityCairoEgypt Environmental Radioative Pollution Department Hot Laboratories CentreAEACairoEgypt

Elemental analysis of iron ore samples and first industrial iron production prepared by the Egyptian Iron and Steel Company of Helwan near Cairo were determined by instrumental neutron activation analysis technique. Five samples from each kind were irradiated for a 48 hours at a thermal neutron flux of 4×10 12 n/(cm 2.s) in the first Egyptian research reactor ET RR 1. Also the Pneumatic irradiation Rabbit system (PIRS) attached to the reactor in Inshass, was used to measure the elements of short life time. The gamma ray spectra were recorded by means of the hyper pure germanium detection system. The concentration percentage values of major, minor and trace elements are presented. The long and short lived isotopes were considered. A comparative study and a discussion on the elemental concentration values are given.

关键词： elemental analysis Egyptian iron samples neutron activation analysis