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CaMoO_4:Dy^(3+),K^+ near White Light Emitting phosphor:structural,Optical and Dielectric properties

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Journal of Materials science & Technology 2013年第7期29卷 633-638页

作者： s.K.sharma s.Dutta s.som p.s.Mandal Department of Applied physics Indian School of MinesDhanbad 826004India

Undoped, Dy^3＋ doped and Dy^3＋, K^＋ codoped calcium molybdate phosphors have been synthesized by solid-state reaction method. X-ray diffraction studies reveal the tetragonal structure of the prepared phosphors having crystallite size 15-50 nm. scanning electron microscopy （sEM） studies reveal the morphology and crystallite size of the prepared phosphors. photoluminescence studies indicate that there are blue and yellow emissions at 489 and 576 nm, respectively corresponding to Dy^3＋ ion. The introduction of K＋ ion significantly influences the blue and yellow emissions which causes the near white light emission from this codoped phosphor. The intense absorption peak of the codoped phosphor at 210 nm is attributed to the band gap and a shoulder at 240 nm appears due to charge transfer from oxygen ions to neighbouring molybdenum ions. The band gap of the codoped phosphor is calculated as 5.5 eV from the absorption studies. The dielectric properties such as permittivity and dielectric loss are studied as a function of *** The authors are thankful to the Department of science and Technology, New Delhi （Government of India） for funding this work under the project sR/FTp/ps-087/2010.

关键词： X-ray diffraction photoluminescence Absorption Dielectric

Light Hadron production in proton-proton Collisions at Different LHC Energies： Measured Data versus a Model

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Chinese physics Letters 2014年第8期31卷 38-41页

作者： p.Guptaroy s.Guptaroy Departmentofphysics RaghunathpurCollegeRaghunathpur723133India Departmentofphysics BasantideviCollegeKolkata700029India

Experiments involving proton-proton collisions at energies √sNN=0.9, 2. 76 and 7 Te V in the large hadron collider produce a vast amount of high-precision data. In this work, we analyze two aspects of the measured data, viz., （i） the pT-spectra of pions, kaons, proton-antiproton at the above-mentioned energies, and （ii） some of their very important ratio behaviors, in the light of a version of the sequential chain model. The agreements between the measured data and the model-based results are generally found to be modestly satisfactory.

关键词： pROTON-proton interactions REsEARCH COLLIsIONs (Nuclear physics) -- Research COLLIDERs (Nuclear physics) -- Research HADRON colliders pIONs KAONs

Direct photon production at RHIC and LHC-Energies:Measured Data Versus a Model

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Chinese physics Letters 2013年第6期30卷 76-79页

作者： p.Guptaroy s.Guptaroy Department of physics Raghunathpur CollegeP.O.Raghunathpur 723133Purulia(WB)India Department of physics Basantidevi College147B Rashbehari AvenueKolkata 700029 India

We attempt to deal with the direct photon production phenomena in p+p,d+Au and Au+Au collisions at RHIC energy,√sNN=200 GeV and in pb+pb-collisions at LHC energy,√sNN=2.76 TeV on the basis of a non-standard framework outlined in the *** of the model-based results with the measured data on some observables reveal fair agreement and they are modestly consistent with the results obtained by some other models of'standard'framework.

关键词： observable energy LHC

Navigating the complexities of perianal Crohn’s disease:Diagnostic strategies,treatment approaches,and future perspectives

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World Journal of Gastroenterology 2024年第44期30卷 4745-4753页

作者： Jai p singh Maryam Aleissa Ernesto R Drelichman Vijay K Mittal Jasneet s Bhullar Department of surgery-Colon and Rectal surgery Ascension Providence HospitalSouthfieldMI 48075United States Department of surgery-Colon and Rectal surgery Ascension Providence HospitalMichigan State University College of Human MedicineSouthfieldMI 48075United States Department of surgery Ascension Providence HospitalMichigan State University College of Human MedicineSouthfieldMI 48075United States

This article discusses the literature review article by pacheco et al published in July 2024;the authors provided good reviews of perianal Crohn’s disease(CD),and challenges faced by clinicians in the ***,characterized by its chronic and relapsing nature,is an idiopathic condition that can involve any segment of the gastrointestinal *** disease impacts up to 40%of patients with CD,with perianal fistulas constituting up to 80%of perianal *** CD can be highly incapacitating and profoundly diminish the overall well-being of *** management focuses on controlling the perianal sepsis and treating luminal *** are crucial to the treatment approach,and results have been *** surgery focuses on controlling the sepsis,with more definitive treatments being fistula surgery,fecal diversion,and proctectomy as the last *** manuscript briefly describes the burden of CD,the challenges posed by perianal CD,and the role of different treatment modalities from colorectal surgeon’s perspective.

关键词： Crohn’s disease perianal Fistula Fistulotomy Biologics stem cell therapy

An investigation into flow mode transition and pressure fluctuations for fluidized dense-phase pneumatic conveying of fine powders

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particuology 2014年第5期12卷 187-195页

作者： A.Mittal s.s.Mallick p.W.Wypych Department of Mechanical Engineering Thapar UniversityPatialaPunjab 147004India Faculty of Engineering and Information sciences University of WollongongWollongongNSW 2500Australia

This paper presents the results of an ongoing investigation into the fluctuations of pressure signals due to solids-gas flows for dense-phase pneumatic conveying of fine powders. pressure signals were obtained from pressure transducers installed along different locations of a pipeline for the fluidized dense-phase pneumatic conveying of fly ash （median particle diameter 30μm; particle density 2300 kg/m^3; loose- poured bulk density 700 kg/m^3） and white powder （median particle diameter 55 p.m; particle density 1600 kg/m^3 ; loose-poured bulk density 620 kg/m^3） from dilute to fluidized dense-phase. standard deviation and shannon entropy were employed to investigate the pressure signal fluctuations. It was found that there is an increase in the values of shannon entropy and standard deviation for both of the prod- ucts along the flow direction through the straight pipe sections. However, both the shannon entropy and standard deviation values tend to decrease after the flow through bend（s）, This result could be attributed to the deceleration of particles while flowing through the bends, resulting in dampened particle fluctua- tion and turbulence. Lower values of shannon entropy in the early parts of the pipeline could be due to the non-suspension nature of flow （dense-phase）, i.e., there is a higher probability that the particles are concentrated toward the bottom of pipe, compared with dilute-phase or suspension flow （high velocity）, where the particles could be expected to be distributed homogenously throughout the pipe bore （as the flow is in suspension）. Changes in straight-pipe pneumatic conveying characteristics along the flow direction also indicate a change in the flow regime along the flow.

关键词： Fluidized dense-phase pneumatic conveying Fine powders shannon entropy Flow transition particle turbulence

Interfacial Reactions and Cubic Neodymium Oxide Formation in Low Dispersed Nd203-siO2 system by Wet Chemical Method

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Chinese physics Letters 2009年第1期26卷 202-204页

作者： s. Duhan p. Aghamkar Materials science Lab Department of Applied Physics G. J. University of Science and Technology Hisar-125001 India Department of physics Chaudhary Devi Lal University Sirsa-125055 India

Neodymium （binary oxide） powders are synthesized by a solgel technique. prepared powders are heat treated under different temperature/or different time duration and obtained nanostructure of Nd. Metal particle have diameters in the range 7.8-1.6 nm. It is found that the heat treatment plays an important role to produce different structure of Nd-doped silica matrix. The peak position shifts to lower angle as the size of the nano metal oxide particles size increases.

关键词： INTERFACEs (physical sciences) NEODYMIUM METALLIC oxides METALs -- Heat treatment NANOsTRUCTUREs sILICA

Non-spherical Gravitational Collapse of strange Quark Matter

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Chinese physics Letters 2008年第5期25卷 1568-1570页

作者： Zade s s patil K D Mulkalwar p N Department of Mathematics J. B. College of Science Wardha India Department of Mathematics B. D. College of Engineering Sewagram Wardha India Department of Computer science Amolakchand Mahavidyalaya Yavatmal India

We study the non-spherical gravitational collapse of the strange quark null fluid. The interesting feature which emerges is that the non-spherical collapse of charged strange quark matter leads to a naked singularity whereas the gravitational collapse of neutral quark matter proceeds to form a black hole. We extend the earlier work of Harko and Cheng [phys. Lett. A 266 （2000） 249] to the non-spherical case.

关键词： NAKED sINGULARITIEs COsMIC CENsORsHIp spACETIMEs

Multi-year MODIs active fire type classification over the Brazilian Tropical Moist Forest Biome

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International Journal of Digital Earth 2017年第1期10卷 54-84页

作者： D.p.Roy s.s.Kumar Geospatial sciences Center of Excellence South Dakota State UniversityBrookingsSDUSA

The Brazilian Tropical Moist Forest Biome(BTMFB)spans almost 4 million km^(2) and is subject to extensive annual fires that have been categorized into deforestation,maintenance,and forest fire *** on fire types is important as they have different atmospheric emissions and ecological impacts.A supervised classification methodology is presented to classify the fire type of MODerate resolution Imaging spectroradiometer(MODIs)active fire detections using training data defined by consideration of Brazilian government forest monitoring program annual land cover maps,and using predictor variables concerned with fuel flammability,fuel load,fire behavior,fire seasonality,fire annual frequency,proximity to surface transportation,and local *** fire seasonality,local temperature,and fuel flammability were the most influential on the *** fire type results for all 1.6 million MODIs Terra and Aqua BTMFB active fire detections over eight years(2003–2010)are presented with an overall fire type classification accuracy of 90.9%(kappa 0.824).The fire type user’s and producer’s classification accuracies were respectively 92.4%and 94.4%(maintenance fires),88.4%and 87.5%(forest fires),and,88.7%and 75.0%(deforestation fires).The spatial and temporal distribution of the classified fire types are presented and are similar to patterns reported in the available recent literature.

关键词： Earth observation land cover remote sensing

Rock mechanical investigation of strata loading characteristics to assess caving and requirement of support resistance in a mechanized powered support longwall face

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International Journal of Mining science and Technology 2016年第6期26卷 1081-1087页

作者： Aveek Mangal p.s.paul Department of Mining Engineering Indian Institute of Technology(Indian School of Mines)Dhanbad826004JharkhandIndia

Longwall mining is one of the most acclaimed and widely used in underground method for coal extraction. The interaction of powered supports with the roof is the key issue in strata mechanics of longwall mining. Controlled caving of rock mass is a prerequisite pro thriving exploitation of coal deposits by longwall retreat with caving technique and support resistance has evolved as the most promising and effective scientific tool to predict various aspects related to strata mechanics of such workings. Load density,height of caving block, distance of fractured zone ahead of the face, overhang of goaf and mechanical strength of the debris above and below the support base have been found to influence the magnitude of load on supports. Designing powered support has been attempted at the different countries in different methods. This paper reviews the mechanism of roof caving and the conventional approaches of caving behaviour and support resistance requirement in the context of major strata control experiences gained worldwide. The theoretical explanation of the mechanism of roof caving is still continuing with consistently improved understanding through growing field experiences in the larger domain of geo-mining conditions and state-of-art strata mechanics analysis and monitoring techniques.

关键词： Longwall mining Geo-mechanics Caving behaviour support resistance