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Journal of Advanced Dielectrics 2016年第4期6卷 45-52页

作者： T.Sreenivasu P.Tirupathi k.Prabahar B.Suryanarayana k.chandra mouli Department of Engineering Physics Andhra University College of Engineering Visakhapatnam-530003India Department of Physics Rajiv Gandhi University of knowledge Technologies(AP-IIIT)Rk Valley-516330 India Advanced Magnetic Group Defense Metallurgical Research Laboratory Hyderabad-500058 India

The solid solutions of(1-x)LaFeO_(3–x)BaTiO_(3)(0.0≤x≤0.25)have been synthesized successfully by the conventional solid-state reaction *** temperature(RT)X-ray diffraction studies reveal the stabilization of orthorhombic phase with Pbnm space *** solubility in the perovskite series was demonstrated up to x=*** dielectric permittivity shows colossal dielectric constant(CDC)at *** doping of BaTiO_(3)in LaFeO_(3)exhibit pronounced CDC up to a composition x=0.15,further it starts to *** frequency-dependent dielectric loss exhibits polaronic conduction,which can attribute to presence of multiple valence of *** relaxation frequency and polaronic conduction mechanism was shifted towards RT as function of ***,large magnetic moment with weak ferromagnetic behavior is observed in doped LaFeO_(3) solid solution,which might be the destruction of spin cycloid structure due to insertion of Ti in Fe–O–Fe network of LaFeO_(3).

关键词： Multiferroic ferromagnetic ceramics.

Graphene derivatives as efficient hole transport materials for lead-free double perovskite（Cs2SnI6） solar cells: a numerical study

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Optoelectronics Letters 2025年第3期21卷 155-159页

作者： Sarita YADAV Saral k.GUPTA chandra Mohan Singh NEGI Department of Physical Science Banasthali Vidyapith

The double perovskite Cs2SnI6has notable optical and electrical characteristics, rendering it a highly prospective candidate for deployment as the absorber layer in perovskite solar cells （PSCs）. We simulated the performance of PSCs using lead-free Cs2SnI6double perovskite absorber layer and graphene derivatives, namely graphene oxide （GO） and reduced graphene oxide （rGO）, as hole transport layers （HTLs）. Our findings show that r GO offers an excellent hole extraction property with minimal interfacial recombination compared to GO.

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A review on perovskite solar cells (PSCs),materials and applications

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Journal of Materiomics 2021年第5期7卷 940-956页

作者： N.Suresh kumar k.chandra Babu Naidu Department of Physics JNTUA College of EngineeringAnantapuramu515002A.PIndia Dept.of Physics GITAM Deemed to be UniversityBangalore562163KarnatakaIndia

In recent years,the perovskite solar cells have gained much attention because of their ever-increasing power conversion efficiency(PCE),simple solution fabrication process,flyable,light-weight wearable and deployable for ultra-lightweight space and low-cost materials constituents *** the last few years,the efficiency of perovskite solar cells has surpassed 25%due to high-quality perovskite-film accomplished through low-temperature synthesis techniques along with developing suitable interface and ***,the stability of perovskite solar cells has attracted much well-deserved *** this article we have focused on recent progress of the perovskite solar cells regarding their crystallinity,morphology and synthesis ***,demonstrated different layers such as electron transport-layers(ETLs),hole transport-layers(HTLs)and buffer-layers utilized in perovskite solar-cells,considering their band gap,carrier mobility,transmittance *** of various tin(Sn),carbon and polymer-based perovskite solar cells and their potential of commercialization feasibility has also been discussed.

关键词： Perovskite solar-cells Power conversion efficiency Hole transport layer Electron transport layer Buffer layer Photovoltaic devices

The present status and future prospects of forest vegetation in part of Nanda Devi Biosphere Reserve(a World Heritage Site),India

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Journal of Forestry Research 2015年第4期26卷 897-904页

作者： Balwant Rawat Sanjay Gairola k.chandra Sekar Ranbeer S.Rawal G.B.Pant Institute of Himalayan Environment and Development Kosi-KatarmalAlmoraUttarakhand 263643India Forest Ecology and Environment Division Forest Research InstituteDehradunUttarakhand 248006India Society for the Conservation of Nature Parnkuti Anantpur University RoadRewaMadhya PradeshIndia

We studied forest vegetation at Lata-Tolma- Phagti, a protected area and part of Nanda Devi Biosphere Reserve in the western Himalaya. We analyzed community composition, population structure, regeneration patterns, and projected development of future compositional patterns. We sampled ten 10 x 10 m quadrat for tree species in each of 30 forest stands. We sampled shrubs in ten 5 x 5 m quadrat, and herbs in twenty 1 x 1 m quadrat within each forest stand. We recorded 248 plant species from 8 forest communities. Broadly the demographic profiles at study sites exhibited progressive structures suggesting long term persistence of the communities/species. Density--diameter distribution revealed greater proportions of seedlings and a significant decline （P 〈 0.05） in the proportion of trees in older age/size classes. Of the 23 recorded tree species, 13.0 % showed good, 52.2 % fair, 26.1% poor and 8.7 % no regeneration. Differences in regeneration by species are indicative of future foreststructure and dynamics. Assessment of changes in structure of forest types provides baseline data for development of priorities for conservation of other representative land- scapes in the reserve as well as in the Himalaya.

关键词： Regeneration pattern Population structure Compositional changes

Seasonal changes in TC and WSOC and their ^13C isotope ratios in Northeast Asian aerosols： land surface–biosphere–atmosphere interactions

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Acta Geochimica 2017年第3期36卷 355-358页

作者： chandra mouli Pavuluri kimitaka kawamura Institute of Surface-Earth System Science Tianjin University Tianjin 300072 China Institute of Low Temperature Science Hokkaido UniversitySapporo 060-0819 Japan Chubu Institute for Advanced Studies Chubu University Kasugai 487-8501 Japan

In order to understand the relative importance of anthropogenic and biological sources of carbonaceous aerosols in Northeast Asia,we measured total carbon(TC)and water-soluble organic carbon(WSOC)and their stable carbon isotope ratios(d^(13)C)in total suspended particulates collected from Sapporo,northern Japan(43.07°N,141.36°E)over a 1-year period(during 2 September 2009and 5 October 2010).Temporal variations of TC showed a gradual decrease from mid-autumn to winter followed by a gradual increase to growing season with a peak in early *** d^(13)C_(TC)and d^(13)C_(WSOC)showed very similar temporal trends with a gradual enrichment of^(13)C from mid-autumn to winter followed by a depletion in the^(13)C to early summer and thereafter it remained stable,except for few *** on the results obtained together with the air mass trajectories,we found that biogenic emissions including biological particles(e.g.,pollen)and secondary organic aerosol formation from biogenic volatile organic compounds are the important sources of carbonaceous aerosols in spring/summer whereas fungal spores from soil and biomass burning and enhanced fossil fuel combustion contribute significantly in autumn/winter and in winter,respectively,in Northeast Asia.

关键词： Carbonaceous aerosols Stable carbon isotope ratios Sources Northeast Asia

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数据库查询理论

计算机科学 1992年第5期19卷 71-77页

作者： Ashok k.chandra 范明

一、引言从 Codd 引进关系数据库开始,在理解怎样才能从数据库中提取数据方面已做了大量工作。已经提出和开发了许多数据库系统和查询语言,包括 SQL,QBE,QUEL,L-DL 等。与此同时,数据库的查询理论已成长为一个丰满的技术领域,这一发展... 详细信息

一、引言从 Codd 引进关系数据库开始,在理解怎样才能从数据库中提取数据方面已做了大量工作。已经提出和开发了许多数据库系统和查询语言,包括 SQL,QBE,QUEL,L-DL 等。与此同时,数据库的查询理论已成长为一个丰满的技术领域,这一发展把更重实效的开发建立在对问题的全面理解之上。确实,现在逻辑程序设计方面开展的研究就是这种情况。本文的目的不是全面地综述数据库查询理论,而是指出随着该领域的发展,使得该领域成型的一些思想。二、一阶查询和关系代数第一个重要的思想来自 Codd。

关键词：数据库查询

SYNTHESIS, CHARACTERIZATION AND ION TRANSPORT PROPERTIES OF HOT-PRESSED SOLID POLYMER ELECTROLYTES (1-x) PEO:x kI

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Chinese Journal of Polymer Science 2013年第2期31卷 302-308页

作者： Angesh chandra Archana chandra k. Thakur Department of Applied Physics Shri Shankaracharya Institute of Prof. Manag. & Tech.Raipur 492015 C.G. India Department of Applied Chemistry Raipur Institute of TechnologyRaipur 492101 C.G. India

Synthesis and ion transport properties of hot-pressed solid polymer electrolytes （SPEs）, （l-x） PEO： x kI, where x is the content of kI in wt%, are reported. A hot-press technique has been used for the formation of the polymeric membranes in place of the usual solution cast method. The composition （80 PEO：20 kI） was identified as the highest conducting polymer electrolyte on the basis of compositional dependent conductivity studies of PEO：kI films. A conductivity enhancement of more than two orders of magnitude from that of the pure PEO was achieved. Materials characterization and ion transport mechanism were explained by using various experimental techniques.

关键词： Solid polymer electrolyte Hot-press technique Ionic conductivity Ionic mobility XRD Polymeric battery.

Simulation and Optimization of Energy Efficiency and Total Enthalpy Analysis of Sand Based Packed Bed Solar Thermal Energy Storage

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Frontiers in Heat and Mass Transfer 2024年第4期22卷 1043-1070页

作者： Matiewos Mekonen Abera Venkata Ramayya Ancha Balewgize Amare L.Syam Sundar kotturu V.V.chandra mouli Sambasivam Sangaraju Faculty of Mechanical Engineering Jimma Institute of TechnologyJimma UniversityP.O.Box 378JimmaEthiopia Aksum University Shire CampusAksumP.O.Box 1010Ethiopia Department of Mechanical Engineering College of EngineeringPrince Mohammad Bin Fahd UniversityAl-Khobar31952Saudi Arabia Department of Mechanical and Industrial Engineering College of EngineeringMajmaah UniversityAl-Majmaah11952Saudi Arabia NationalWater and Energy Center United Arab Emirates UniversityAl Ain15551United Arab Emirates

This study is focused on the simulation and optimization of packed-bed solar thermal energy storage by using sand as a storage material and hot-water is used as a heat transfer fluid and storage as *** analysis has been done by using the COMSOL multi-physics software and used to compute an optimization charging time of the *** that control this optimization are storage height,storage diameter,heat transfer fluid flow rate,and sand bed particle *** result of COMSOL multi-physics optimized thermal storage has been validated with Taguchi ***,the optimized parameters of storage are:storage height of 1.4m,storage diameter of 0.4 m,flow rate of 0.02 kg/s,and sand particle size 12 *** these parameters,the storage diameter result is the highest influenced optimized parameter of the thermal storage fromthe ANOVA *** nominal packed bed thermal storage,the charging time needed to attain about 520 k temperature is more than 3500 s,while it needs only about 2000 s for the optimized storage which is very significant *** charging energy efficiency of the optimized is greater than the nominal and previous concrete-based storage by 13.7%,and 13.1%,respectively in the charging time of 2700 s.

关键词： Optimization solar thermal energy storage Taguchimethod COMSOLmultiphysics packed bed thermal storage charging time

On uniform nonintegrability for a sequence of random variables

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On uniform nonintegrability for a sequence of random variabl...

Influence of local stiffeners and cutout shapes on the vibration and stability characteristics of quasi-isotropic laminates under hygro-thermo-mechanical loadings

第十届海峡两岸统计与概率研讨会

作者： Tapas k.chandra 胡殿中 Andrew Rosalsky Applied Statistics Division Indian Statistical Institute Department of Mathematics “National Tsing Hua University” Department of Statistics University of Florida

In this correspondence, we introduce the notion of a sequence of random variables being uniformly nonintegrable. Sets of sufficient and, separately, necessary conditions for uniform nonintegrablility are presented and we also establish two equivalent characterizations of uniform nonintegrablility, one of which is a uniform nonintegrablility analogue to the celebrated de La Vallee Poussin criterion for uniform integrablility. Several illustrative examples are presented.

关键词： de La Vallee Poussin criterion for uniform integrability nonintegrable random variables sequence of uniformly nonintegrable random variables

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Defence Technology（防务技术） 2022年第12期18卷 2107-2124页

作者： T.Rajanna k.S.Subash chandra k.Venkata Rao Department of Civil Engineering B.M.S College of EngineeringBengaluru560019India Research Scholar B.M.S College of EngineeringBengaluru560019India Department of Mechanical Engineering B.M.S Evening College of EngineeringBengaluru560019India Department of Mechanical Engineering Government PolytechnicBagepalli561207India

The perforated stiffened panel is generally found as a sub-component of sophisticated *** fundamental purpose of this panel is to withstand against buckling under complicated loading and environmental ***,an accurate knowledge of critical buckling behaviour of stiffened panels is very much essential for a reliable and lightweight structural *** this paper,the focus is on quasi-laminated panels with different cutout shapes of various sizes and their responses to hygrothermal environments under nonlinearly varying edge loads and is compared with the locally stiffened *** this,the modelling of the panel and stiffener is done by adopting nine-noded heterosis plate elements and three noded beam elements *** stiffener formulation is suitably modified in order to take the torsional effect also into consideration along with the effect of shear ***,the plate and the stiffener elements are treated separately,and then the displacement compatibility is maintained between them by using the transformation *** a given loading and geometric discontinuity,the stress distribution within the perforated panel is highly non-uniform in nature and hence a dynamic approach has been used to calculate buckling loads by adopting two sets of boundary conditions,one set for pre-buckling stress analysis and the second set for buckling *** different quasi-isotropic stacking sequences are deliberated in this work by varying different ply-orientation in each *** study also addresses the effect of various parameters such as nonlinear loads,hygro-thermal loads,cutout size and shapes,position of cutout,stiffener parameters,stacking sequences,thickness of plate and boundary conditions.

关键词： Locally stiffened panels Buckling Vibration Cutouts Heterosis Hygrothermal environment