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Rare earth(Eu^(2+),Ce^(3+)) activated BaAl_2si_2O_8 blue emitting phosphor

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journal of Rare Earths 2014年第7期32卷 593-597页

作者： V.B.Pawade N.s.Dhoble s.j.Dhoble Department of Applied-Physics Laxminarayan Institute of Technology Department of Chemistry Sevadal Mahila Mahavidyalay Department of Physics RTM Nagpur University

Blue emitting rare earth（Eu2＋,Ce3＋） doped BaAl2si2O8 phosphors were synthesized by combustion methods at 600 oC. BaAl2si2O8： Eu2＋ phosphor showed isolated broad blue emission band at 455 nm, when it was excited with the wavelength of 329 nm. Whereas BaAl2si2O8：Ce3＋ phosphor exhibited blue emission band at 442 nm, under 303 nm excitation wavelength. These observed emission bands of Eu2＋ and Ce3＋ ions corresponded to 5d-4f allowed transitions. The position of emission band was calculated by using the equationE=Q[1-〔V/4〕^1/V）]× 10 （nEar/80）Also the spin orbit splitting difference in the ground state levels of Ce3＋ ion was studied by Gaussian curve fitting. Broad absorption and emission bands in blue regions made prepared phosphors a promising blue host for the white-LEDs.

关键词： optical materials spectroscopy luminescence crystal fields rare earths

C_c(X)spaces with X Locally Compact

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Acta Mathematica sinica,English series 2007年第9期23卷 1593-1600页

作者： j.C.FERRANDO s.MOLL Centro de Investigación Operativa Universidad Miquel Hernández Departamento de Matemática Aplicada Universidad Politécnica

In this paper, we show, among other results, that if X is a [separable] locally compact space X [satisfying the first countability axiom] then the space Cc （X） has countable tightness [if and only if it has bounding tightness] if and only if it is Frechet-Urysohn, if and only if Cc （X） contains a dense （LM） subspace and if and only if X is a-compact.

关键词： Frechet-Urysohn space countable [bounding] tightness (LM)-space

ON A CLAss OF ANALYTIC FUNCTIONs RELATED TO CONIC DOMAINs AND AssOCIATED WITH CARLsON-sHAFFER OPERATOR

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Acta Mathematica scientia 2012年第4期32卷 1399-1407页

作者： s.Hussain j.sokól Mathematics Department COMSATS Institute of Information TechnologyAbbottabadPakistan Department of Mathematics Rzeszów University of Technologyul.W.Pola 235-959 RzeszówPoland

Making use of the Carlson-shaffer convolution operator, we introduce and study a new class of analytic functions related to conic domains. The main object of this paper is to investigate inclusion relations, coefficient bound for this class. We also show that this class is closed under convolution with a convex function. some applications are also discussed.

关键词： Hadamard product (or convolution) differential subordination Carlson-shaffer operator k-starlike functions k-uniformly convex function

Land use effects on climate in China as simulated by a regional climate model

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science China Earth sciences 2007年第4期50卷 620-628页

作者： j.s.PAL F.GIORGI The Abdus salam International Center for Theoretical Physics Trieste 34100 Italy

A regional climate model (RegCM3) nested within ERA40 re-analyzed data is used to investigate the climate effects of land use change over China. Two 15-year simulations (1987―2001), one with current land use and the other with potential vegetation cover without human intervention, are conducted for a domain encompassing China. The climate impacts of land use change are assessed from the difference between the two simulations. Results show that the current land use (modified by anthropogenic ac- tivities) influences local climate as simulated by the model through the reinforcement of the monsoon circulation in both the winter and summer seasons and through changes of the surface energy budget. In winter, land use change leads to reduced precipitation and decreased surface air temperature south of the Yangtze River, and increased precipitation north of the Yangtze River. Land use change signifi- cantly affects summer climate in southern China, yielding increased precipitation over the region, de- creased temperature along the Yangtze River and increased temperature in the south China area (south-end of China). In summer, a reduction of precipitation over northern China and a temperature rise over Northwest China are also simulated. Both daily maximum and minimum temperatures are affected in the simulations. In general, the current land use in China leads to enhanced mean annual precipitation and decreased annual temperature over south China along with decreased precipitation over North China.

关键词： land use China simulation regional climate model regional climate change

Tsallis holographic dark energy under complex form of quintessence model

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Communications in Theoretical Physics 2023年第2期75卷 157-167页

作者： j sadeghi s Noori Gashti T Azizi Department of Physics Faculty of Basic SciencesUniversity of Mazandaran P.O.Box 47416-95447BabolsarIran

In this paper,we use a Tsallis holographic dark energy model in two forms,interacting and noninteracting cases,to acquire some parameters as the equation of state for the energy density of the Tsallis model in the FRW Universe concerning the complex form of quintessence *** will study the cosmology of complex quintessence by revamping the potential and investigating the scalar field *** we analyze(w-w’)and stability in two cases,*** and *** will explore whether these cases describe a real Universe by calculating fractional energy densityΩ_(D)and concerning two parts of the quintessence field effect(complex and real part)by considering the real part of this field to be a slow-roll *** know that the part in which the fractional energy density(Ω_(D)>1)does not describe a real ***,we specified an interacting coupling parameter b2that depends on the constant parameter of the Tsallis holographic model(δ)with respect to fractional energy density(0.73).Unlike independence between the fractional energy density and interacting coupling in the real quintessence model,we determine a relationship among these parameters in this ***,by plotting some figures,we specify the features of(w-w’)and(ν^(2)_(s))in two cases and compare the result with each other.

关键词： Tsallis holographic model complex form of quintessence model stability

Gene-environment interactions in male reproductive health： special reference to the aryl hydrocarbon receptor signaling pathway

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Asian journal of Andrology 2014年第1期16卷 89-96页

作者： Leon j s Brokken Yvonne Lundberg Giwercman Department of Clinical sciences Molecular Genetic Reproductive Medicine Lund University MalmO Sweden

Over the last few decades, there have been numerous reports of adverse effects on the reproductive health of wildlife and laboratory animals caused by exposure to endocrine disrupting chemicals （EDCs）. The increasing trends in human male reproductive disorders and the mounting evidence for causative environmental factors have therefore sparked growing interest in the health threat posed to humans by EDCs, which are substances in our food, environment and consumer items that interfere with hormone action, biosynthesis or metabolism, resulting in disrupted tissue homeostasis or reproductive function. The mechanisms of EDCs involve a wide array of actions and pathways. Examples include the estrogenic, androgenic, thyroid and retinoid pathways, in which the EDCs may act directly as agonists or antagonists, or indirectly via other nuclear receptors. Dioxins and dioxin-like EDCs exert their biological and toxicological actions through activation of the aryl hydrocarbon-receptor, which besides inducing transcription of detoxifying enzymes also regulates transcriptional activity of other nuclear receptors. There is increasing evidence that genetic predispositions may modify the susceptibility to adverse effects of toxic chemicals. In this review, potential consequences of hereditary predisposition and EDCs are discussed, with a special focus on the currently available publications on interactions between dioxin and androgen signaling.

关键词： androgen receptor aryl hydrocarbon receptor endocrine disrupter

A modified TreePM code

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Research in Astronomy and Astrophysics 2009年第8期9卷 861-873页

作者： Nishikanta Khandai j. s. Bagla Harish-Chandra Research Institute

We discuss the performance characteristics of using the modification of the tree code suggested by Barnes in the context of the TreePM code. The optimization involves identifying groups of particles and using only one tree walk to compute the force for all the particles in the group. This modification has been in use in our implementation of the TreePM code for some time, and has also been used by others in codes that make use of tree structures. We present the first detailed study of the performance characteristics of this optimization. We show that the modification, if tuned properly, can speed up the TreePM code by a significant amount. We also combine this modification with the use of individual time steps and indicate how to combine these two schemes in an optimal fashion. We find that the combination is at least a factor of two faster than the modified TreePM without individual time steps. Overall performance is often faster by a larger factor because the scheme for the groups optimizes the use of cache for large simulations.

关键词： cosmology large-scale structure of universe -- gravitation -- methods numerical

Peristaltic transport of rheological fluid:model for movement of food bolus through esophagus

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Applied Mathematics and Mechanics(English Edition) 2012年第3期33卷 315-332页

作者： j.C.MIsRA s.MAITI Department of Mathematics Institute of Technical Education and ResearchSiksha 'O' Anusandhan UniversityBhubaneswar 751030India school of Medical science and Technology & Center for Theoretical studies Indian Institute of TechnologyKharagpur 721302India

Fluid mechanical peristaltic transport through esophagus is studied in the paper. A mathematical model has been developed to study the peristaltic transport of a rheological fluid for arbitrary wave shapes and tube lengths. The Ostwald-de Waele power law of a viscous fluid is considered here to depict the non-Newtonian behaviour of the fluid. The model is formulated and analyzed specifically to explore some important information concerning the movement of food bolus through esophagus. The analysis is carried out by using the lubrication theory. The study is particularly suitable for the cases where the Reynolds number is small. The esophagus is treated as a circular tube through which the transport of food bolus takes place by periodic contraction of the esophageal wall. Variation of different variables concerned with the transport phenomena such as pressure, flow velocities, particle trajectory, and reflux is investigated for a single wave as well as a train of periodic peristaltic waves. The locally variable pressure is seen to be highly sensitive to the flow index ＂n＂. The study clearly shows that continuous fluid transport for Newtonian/rheological fluids by wave train propagation is more effective than widely spaced single wave propagation in the case of peristaltic movement of food bolus in the esophagus.

关键词： non-Newtonian fluid food bolus esophagus peristaltic transport flow reversal single wave wave train particle trajectory

Particle size Distribution and Characterization of High siliceous and Microporous Materials

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journal of Materials science & Technology 2005年第4期21卷 563-570页

作者： s.KDurrani j.Akhtar M.Ahmad M.j.Moughal Nuclear Materials Division Pakistan Institute of Nuclear Science and Technology P.O. Nilore Islamabad PakistanNuclear Materials Division Pakistan Institute of Nuclear Science and Technology P.O. Nilore Islamabad PakistanNuclear Physics Divisions Pakistan Institute of Nuclear Science and Technology P.O. Nilore Islamaad PakistanNuclear Materials Division Pakistan Institute of Nuclear Science and Technology P.O. Nilore. Islamabad. Pakistan

Particle size, textural and surface characteristics influence some major technological properties of high siliceous aluminosilicate zeolite and sillicoaluminophosphate （sAPO） microporous materials. A comparative study was furnished for measuring surface characteristics, particle size and particle size distribution using particle size analyzer （PsA） and scanning electron microscope （sEM）. The PsA is capable of measuring particle diameter in micron range. The results of these techniques for estimation of particle size were compared and correlated statistically. student t-test and variance ratio test （F-test） methods were performed for the significance of results by the analysis of variance （ANONA） and multiple-range tests. Textural and surface characteristics were evaluated by Brunauer, Emmett ＆ Teller （BET） volumetric technique and v-αs plotting method. The textural results shows that the external surface area and micropore volume of microporous materials were higher than those of the high siliceous zeolites and its zeotype materials.

关键词： synthesis High siliceous zeolites Microporous materials Particle size distribution Micropore volume sEM