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Acta Geologica Sinica(English Edition) 2019年第6期93卷 1755-1772页

作者： Davood RAEISI hassan MRNEJAD Department of Geology Faculty of ScienceUniversity of TehranTehranIran Department of Geology and Environmental Earth Sciences Miami UniversityOxfordOhioUSA

The Tafresh granitoids are located at the central part of the Urumieh-Dokhtar Magmatic Arc(UDMA)in *** rocks,mainly consisting of diorite and granodiorite,were emplaced during the Early *** are composed of varying proportions of plagioclase+K-feldspar+hornblende±quartz±*** diagrams and chemical indices of amphibole phases reveal a calc-alkaline affinity and fall clearly in the crust-mantle mixed source *** estimated pressure,derived from Al in amphibole barometry,is approximately 3 *** granitoids are I-type,metaluminous and belong to the calc-alkaline *** are all enriched in light rare earth elements and large ion lithophile elements,depleted in high field strength elements and display geochemical features typical of subduction-related calc-alkaline arc *** crystal size distribution(CSD)line patterns from the granitoids show a non-straight trend which points to the effect of physical processes during *** presence of numerous mafic enclaves,sieve texture and oscillatory zoning along with the CSD results show that magma mixing in the magma chamber had an important role in the petrogenesis of Tafresh ***,the CSD analysis suggests that the plagioclase crystals were crystallized in a time span of less than 1000 years,which is indicative of shallow depth magma crystallization.

关键词： crust-mantle mixed source I-type subduction crystal size distribution magma mixing Urumieh-Dokhtar Magmatic Arc

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

New Exact Solutions of Two Nonlinear Physical Models

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Communications in Theoretical Physics 2010年第4期53卷 596-604页

作者： M.M.hassan Mathematics Department Faculty of Science Minia University

Abundant new exact solutions of the Schamel-Korteweg-de Vries （S-KdV） equation and modified Zakharov- Kuznetsov equation arising in plasma and dust plasma are presented by using the extended mapping method and the availability of symbolic computation. These solutions include the Jacobi elliptic function solutions, hyperbolic function solutions, rational solutions, and periodic wave solutions. In the limiting cases, the solitary wave solutions are obtained and some known solutions are also recovered.

关键词： modified Zakharov-Kuznetsov equation Schamel-Korteweg-de Vries equation traveling and periodic wave solutions extended mapping method

On Generalized Douglas–Weyl(α, β)-Metrics

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Acta Mathematica Sinica,English Series 2015年第10期31卷 1611-1620页

作者： Akbar TAYEBI hassan SADEGHI Department of Mathematics Faculty of Science University of Qom

In this paper, we study generalized Douglas-Weyl （α,β）-metrics. Suppose that a regular （α,β）-metric F is not of Randers type. We prove that F is a generalized Douglas-Weyl metric with vanishing S-curvature if and only if it is a Berwald metric. Moreover, by ignoring the regularity, if F is not a Berwald metric, then we find a family of almost regular Finsler metrics which is not Douglas nor Weyl. As its application, we show that generalized Douglas-Weyl square metric or Matsumoto metric with isotropic mean Berwald curvature are Berwald metrics.

关键词： Generalized Douglas Weyl metric Weyl metric Douglas metric S-curvature

Impact of Drain Effluent on Surficial Sediments in the Mediterranean Coastal Wetland: Sedimentological Characteristics and Metal Pollution Status at Lake Manzala, Egypt

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Journal of Ocean University of China 2019年第4期18卷 834-848页

作者： FARHAT hassan I. Geology Department Faculty of Science Suez University

Surface sediments were collected from Lake Manzala, the Mediterranean coastal wetland located to the east of the Nile Delta, Egypt, to assess the effect of drain effluent on the spatial variations of sedimentary characteristics and heavy metal pollution. Grain-size compositions, textures, and heavy metal distribution patterns in sediments are presented using GIS technique. Results of the analysis of the sediment showed a clear effect of drain effluent, with an increase in fine fractions and homogeneous suspensions in transportation mode. Lake sediments were dominated by sandy mud textures, and mode of transportation was homogeneous sus- pension and rolling. Spatial distribution of heavy metals (Fe, Mn, Zn, Cu, Ni, Cr, and Pb) was studied in the lake’s surficial sediments, along with their relationship to drain effluent and their contamination status in the ecological system. Heavy metal pollution status was assessed by means of accepted sediment quality guidelines and contamination assessment methods (contamination factor, con- tamination degree, modified contamination degree, geo-accumulation, and enrichment factor). Among the determined heavy metals, Pb had the most ecological risk. Generally, the heavy metals in the surface sediments indicated pollution risk ranging from moderate to considerable, particularly, in those sites facing drains and inlets that had the highest toxic effluent. The results were interpreted by statistical means. A cluster analysis defined areas facing drain discharge and inlets as separated groups. ANOVA indicated that most of the sedimentation and studied metals directed this clustering.

关键词： Lake Manzala Mediterranean wetland metal pollution sedimentological characteristics

Amelioration of altered antioxidant enzyme activity by Satureja khuzistanica essential oil in alloxan-induced diabetic rats

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Chinese Journal of Natural Medicines 2014年第9期12卷 672-676页

作者： hassan Ahmadv Razi Herbal Researches Center Lorestan University of Medical Sciences Department of Biochemistry Faculty of Medicine Lorestan University of Medical Sciences

AIM: To examine the possible protective effect of Satureja khuzistanica essential oil(SKE) on antioxidant enzyme activity in alloxan-induced Type 1 diabetic rats. METHOD: Thirty Sprague-Dawley male rats were divided into three groups randomly; group one as control, group two diabetic, with no treatment, and group three treatment with SKE at 500 ppm in drinking water, respectively. Diabetes was induced in the second and third groups by alloxan injection subcutaneously. After eight weeks, animals were anaesthetized. Blood samples were also collected before killing to measure antioxidant enzymes activity. RESULTS: SKE significantly increased the serum level of glutathione and the serum activity of glutathione peroxidase, superoxide dismutase, and catalase in the treated group compared with the diabetic untreated group. CONCLUSION: The findings showed that SKE exerts beneficial effects on the antioxidant enzymes activity in alloxan-induced Type 1 diabetic rats.

关键词： Diabetes Antioxidant enzyme activity Satureja khuzistanica Essential oil

SOME RESULTS ON CONTROLLED FRAMES IN HILBERT SPACES

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Acta Mathematica Scientia 2016年第3期36卷 655-665页

作者： Kamran MUSAZADEH hassan KHANDANI Department of Mathematics College of ScienceMahabad BranchIslamic Azad University

We use two appropriate bounded invertible operators to define a controlled frame with optimal frame bounds. We characterize those operators that produces Parseval controlled frames also we state a way to construct nearly Parseval controlled frames. We intro- duce a new perturbation of controlled frames to obtain new frames from a given one. Also we reduce the distance of frames by appropriate operators and produce nearly dual frames from two given frames which are not dual frames for each other.

关键词： frames Parseval frames dual frames controlled frames reconstruction formula perturbation

Composition Dependence of Surface Phonon Polariton Mode in Wurtzite InxGa1-xN （0 ≤ x ≤ 1） Ternary Alloy

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Chinese Physics Letters 2008年第12期25卷 4378-4380页

作者： S. S. Ng Z. hassan H. Abu hassan Nano-Optoelectronics Research and Technology Laboratory School of Physics Universiti Sains Malaysia 11800 Minden Pulau Pinang Malaysia

We present a theoretical study on the composition dependence of the surface phonon polariton （SPP） mode in wurtzite structure α-InxGa1-xN ternary alloy over the whole composition range. The SPP modes are obtained by the theoretical simulations by means of an anisotropy model. The results reveal that the SPP mode of α-InxGa1-xN semiconductors exhibits one-mode behaviour. From these data, composition dependence of the SPP mode with bowing parameter of-28.9 cm^-1 is theoretically obtained.

关键词： field emission molybdenum dioxide enhancement factor

Naturally Occurring Self-Reactive CD4^+CD25^+ Regulatory T Cells: Universal Immune Code

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Cellular & Molecular Immunology 2007年第3期4卷 197-201页

作者： Nafiseh Pakravan Agheel Tabar Molla hassan Zuhair Muhammad hassan Department of Immunology Faculty of Medical Sciences Tarbiat Modares University Tehran Iran Faculty of Sciences Tarbiat Moallem University Tehran Iran Department of Immunology Faculty of Medical Sciences Tarbiat Modares University Tehran Iran

Naturally occurring thymus-arisen CD4^＋CD25^＋ regulatory T （Treg） cells are considered to play a central role in self-tolerance. Precise signals that promote the development of Treg cells remain elusive, but considerable evidence suggests that costimulatory molecules, cytokines, the nature of the TCR and the niche or the context in which the T cell encounters antigen in the thymus play important roles. Analysis of TCR from Treg cells has demonstrated that a large proportion of this population has a higher avidity to self-antigen in comparison with TCR from CD4^＋CD25^＋ cells and that peripheral antigen is required for their development, maintenance, or expansion. Treg cells have been shown to undergo expansion in the periphery, likely regulated by the presence of self-antigen. Many studies have shown that the involvement of Treg cells in the tolerance induction is antigen-specific, even with MHC-mismatched, in transplantation/graft versus host disease （GVHD）, autoimmunity, cancer, and pregnancy. Theses studies concluded a vital role for self-reactive Treg cells in maintenance of the body integrity. Based on those studies, we hypothesize that self-reactive Treg cells are shared among all healthy individuals and recognize same self-antigens and their TCR encodes for few dominant antigens of each organ which defines the healthy self. These dominant self antigens can be regarded as ＂universal immune code＂. Cellular ＆ Molecular Immunology.

关键词： regulatory T cell pregnancy GVHD autoimmunity dominant self-antigen

Statistical Inference of Chen Distribution Based on Two Progressive Type-II Censoring Schemes

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Computers, Materials & Continua 2021年第3期66卷 2797-2814页

作者： hassan M.Aljohani Department of Mathematics&Statistics Faculty of ScienceTaif UniversityTaif21944Saudi Arabia

An inverse problemin practical scientific investigations is the process of computing unknown parameters from a set of observations where the observations are only recorded indirectly,such as monitoring and controlling quality in industrial process *** regression can be thought of as linear inverse *** other words,the procedure of unknown estimation parameters can be expressed as an inverse ***,maximum likelihood provides an unstable solution,and the problembecomes more complicated if unknown parameters are estimated from different ***,researchers search for better *** study two joint censoring schemes for lifetime products in industrial process *** practice,this type of data can be collected in fields such as the medical industry and industrial *** this study,statistical inference for the Chen lifetime products is considered and analyzed to estimate underlying *** likelihood and Bayes’rule are both studied for model *** asymptotic distribution of maximumlikelihood estimators and the empirical distributions obtained withMarkov chainMonte Carlo algorithms are utilized to build the interval *** results using tables and figures are adopted through simulation studies and verified in an analysis of the lifetime *** briefly describe the performance of developed methods.

关键词： Chen distributions progressive type-II censoring maximum likelihood mean posterior Bayesian estimation MCMC