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Fe^(3+)-substitution effect on the thermal variation of J-E characteristics and Dc resistivity of quadruple perovskite cacu_(3)Ti_(4)O_(12)

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Journal of Semiconductors 2022年第3期43卷 47-56页

作者： Kunal B.Modi Pooja y.Raval Dolly J.Parekh Shrey K.Modi Niketa P.joshi Akshay R.Makadiya Nimish H.Vasoya Utpal S.joshi Department of Physics Saurashtra UniversityRajkot 360005India Department of Physics C.U.Shah UniversityWadhwan CitySurendranagar 363030India Department of Environment Engineering L.D.Engineering CollegeAhmedabad 380015India Department of Balbhavan Children´s UniversitySector-20Gandhinagar 382015India Department of Physics University School of SciencesGujarat UniversityAhmedabad 380009India

The electrical properties of cubic perovskite series,cacu_(3-x)Ti_(4-x)Fe_(2x)O_(12)with x=0.0,0.1,0.3,0.5,and 0.7,have been studied by employing current density as a function of electric field characteristics registered at different temperatures and thermal variations of direct current electrical resistivity *** of the compositions exhibit strong non-ohmic *** concentration dependence of breakdown field,the temperature at which switching action takes place,and maximum value of current density(J_(max))has been explained on account of structural,microstructural,and positron lifetime *** highest ever reported value of J_(max)=327 mA/cm^(2)has been observed for pristine *** values of the nonlinear coefficient advise the suitability of ceramics for low-voltage varistor *** Arrhenius plots show typical semiconducting *** activation energy values indicate that electric conduction proceeds through electrons with deformation in the system.

关键词： perovskites magnetic materials J-E characteristics capacitor

catalytic effects of cu-co~* on the thermal decomposition of AN and AN/KDN based green oxidizer and propellant samples

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Defence Technology（防务技术） 2018年第3期14卷 250-260页

作者： Pratim Kumar Puran chandra joshi Rajiv Kumar Shelly Biswas Department of Space Engineering & Rocketry Birla Institute of Technology Department of Mechanical Engineering Vidya Vihar Institute of Technology

This paper presents the catalytic effects of cu-co~* catalyst on the decomposition of AN and AN/KDN based oxidizer and propellant samples. Ozawa-Flynn-Wall(OFW) iso-conversional method was used for the kinetic studies and to compute the activation energy(Ea) values for various decomposition steps of the prepared oxidizer and propellant samples in the temperature range of 50 e500c. TG-DTG experiments were carried out for both oxidizer and propellant samples at the heating rates of 3, 5, and 10c/min. AN/KDN based oxidizer samples were prepared by an evaporative co-crystallization method. citric acid sol-gel method was used for the synthesis of cu-co~* catalyst. The propellant sample contains HTPB as the fuel binder along with other ingredients such as TDI, DOA, and Glycerol. The cu-co~* catalyst was used as 2% by weight to the total weight of catalyzed oxidizer and propellant samples. It was observed from the present study that, cu-co~* catalyst helps in reducing the Ea values for AN and AN based propellant samples. However, with the percentage increment of KDN in the AN crystals, Ea value ***, it was observed that cu-co~* catalyst stabilizes the initial partial decomposition of KDN.

关键词：催化氧化剂催化效果热分解 cu 燃料取样 TG-DTG 催化剂

Abscisic Acid Signal off the STARTing Block

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Molecular Plant 2011年第4期4卷 562-580页

作者： Archana joshi-Saha christiane Valon Jeffrey Leung Institut des Sciences du Vegetal Centre National de la Recherche Scientifique UPR2355 1 Avenue de la Terrasse Bat. 23 91198 Gif-sur-Yvette France

The year 2009 marked a real turnaround in our understanding of the mode of abscisic acid （ABA） action. Nearly 25 years had elapsed since the first biochemical detection of ABA-binding proteins in the plasmalemma of Vicia guard cells was reported. This recent--and laudable--achievement is owed largely to the discovery of the soluble ABA receptors whose major interacting proteins happen to be some of the most well-established components of earliest steps in ABA signaling. These soluble receptors, with the double name of PyRABAcTIN RESISTANcE （PyR） or REGULATORy.c.MPONENT OF ABA REcEPTOR （RcAR）, are a family of Arabidopsis proteins of about 150-200 amino acids that share a conserved START domain. The ABA signal transduction circuitry under non-stress conditions is muted by the clade A protein phosphatases 2c （PP2c）（notably HAB1, ABI1, and ABI2）. During the initial steps of ABA signaling, the binding of the hormone to the receptor induces a conformational change in the latter that allows it to sequester the PP2cs. This excludes them from the negative regulation of the downstream ABA-activated kinases （OST1/SnRK2.6/SRK2E, SnRK2.2, and SnRK2.3）, thus unleashing the pathway by freeing them to phosphorylate downstream targets that now include several b-ZIP transcription factors, ion channels （SLAc1, KAT1）, and a NADPH oxidase （AtrbohF）. The discovery of this family of soluble receptors and the rich insight already gained from structural studies of their complexes with different isoforms of ABA, PP2c, and the synthetic agonist pyrabactin lay the foundation towards rational design of chemical switches that can bolster drought hardiness in plants.

关键词： Abiotic/environmental stress hormone biology signal transduction.

Implications of climate change on Streamflow of a Snow-Fed River System of the Northwest Himalaya

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Journal of Mountain Science 2013年第4期10卷 574-587页

作者： Vaibhav SHARMA Varunendra Dutta MISHRA Pawan Kumar joshi Snow and Avalanche Study Establishment Chandigarh 160036 India TERI University Institutional AreaDelhi 110070 India

Air temperature and snow cover variability are sensitive indicators of climate change. This study was undertaken to forecast and quantify the potential streamflow response to climate change in the Jhelum River basin. The implications of air temperature trends （＋0.11℃decade） reported for the entire north-west Himalaya for past century and the regional warming （＋0.7℃/decade） trends of three observatories analyzed between last two decades were used for future projection of snow cover depletion and stream flow. The streamflow was simulated and validated for the year 2007-2008 using snowmelt runoff model （SRM） based on in-situ temperature and precipitation with remotely sensed snow cover area. The simulation was repeated using higher values of temperature and modified snow cover depletion curves according to the assumed future climate. Early snow cover depletion was observed in the basin in response to warmer climate. The results show that with the increase in air temperature, streamfiow pattern of Jhelum will be severely affected. Significant redistribution of streamflow was observed in both the scenarios. Higher discharge was observed during spring-summer months due to early snowmelt contribution with water deficit during monsoon months. Discharge increased by 5%-40% during the months of March to May in 2030 and 2050. The magnitude of impact of air temperature is higher in the scenario-2 based on regional warming. The inferences pertaining to change in future streamflow pattern can facilitate long term decisions and planning concerning hydro-power potential, waterresource management and flood hazard mapping in the region.

关键词： Snowmelt Snow cover depletion curve(ScDc) climate change Global warming Streamflow SRM Jhelum

Scavenging Action of Zinc and Green Tea Polyphenol on cisplatin and Nickel Induced Nitric Oxide Generation and Lipid Peroxidation in Rats

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Biomedical and Environmental Sciences 2004年第4期17卷 402-409页

作者： SEEMA joshi S. K. HASAN RAMESH cHANDRA M. M. HUSAIN R. c. SRIVASTAVA Isabella Thoburn P. G. college Faizabad Road Lucknow 226 007 IndiaIndustrial Toxicology Research Centre P. O. Box. 80 M. G. Marg Lucknow 226 001 IndiaIndustrial Toxicology Research Centre P. O. Box. 80 M. G. Marg Lucknow 226 001 IndiaIndustrial Toxicology Research Centre P. O. Box. 80 M. G. Marg Lucknow 226 001 IndiaR.C.Srivastava Scientist 'F'and Area Coordinator Analytical Toxicology Industrial Toxicology Research Centre P.O.Box80M.G.Marg Lucknow226001UP.INDIA

Objective Toxic metal ions have been implicated in the generation of reactive oxygen species (ROS) and nitric oxide (NO). Metallothionines (MT) and plant flavonoids have been reported in the intervention against oxidative damage. We investigated the effect of zinc induced MT and green tea polyphenol (GTP) in reducing the oxidative responses induced by nickel and platinum. Methods Zinc (10 mg/kg b. wt, sc) was administered to rats twice at a gap of 24hrs and GTP (10 mg/100 mL in drinking water) was fed ad libitum for 8 days. Nickel chloride (150 umol/***, ip) and cisplatin (50 mmol/kg ***, sc) was administered to rats 24 h after Zn or GTP pre-treatment. Animals of all the groups were sacrificed 16 hrs after treatment and biochemical markers for toxicity were monitored. Results Zinc or GTP pre-treatment caused significant protection against nickel or cisplatin enhanced mortality in rats, and reduction in lipid peroxidation and NO. conclusion It is proposed that inhibition of ROS and NO by GTP and zinc may prove useful as a selective pharmacological agent in the amelioration of metal toxicity.

关键词： Green tea polyphenol Zinc Nitric oxide Lipid Peroxidation Nickel cisplatin

Quality of spring water used for irrigation in the Almora District of Uttarakhand, India

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chinese Journal Of Geochemistry 2013年第2期32卷 130-136页

作者： Bhandari N. S. Hemant K. joshi Department of chemistry Kumaun University S. S. J. Campus Almora-263601 Uttarakhand India

This paper aims to propose a quality profile of springs of the study area for irrigation. In the present study, fifty-four springs in Almora have been identified from rural as well as urban localities for calculation of irriga- tional water quality parameters during pre-monsoon, monsoon and post-monsoon, 2008. Spring water samples are collected and analyzed for pH, electrical conductivity (Ec), total dissolved solids (TDS), Na+ , K+ , ca2+ , Mg2+ , HcO3- , cl- , and SO42- . Different irrigation quality parameters viz. salinity, sodium adsorption ratio (SAR), soluble sodium percentage (SSP), residual sodium carbonate (RSc), magnesium hazards (MH) and permeability index (PI) are calculated for the evaluation of spring water quality for irrigation purposes. All springs are found excellent to good based on irrigation quality parameters. Based on Wilcox diagram, about 98% of the water resources are grouped as c1S1 (low-low) and c2S1 (medium-low) classes, so springs are suitable for normal irrigation.

关键词：质量档案灌溉泉水印度钠吸附比水质参数总溶解固体研究区域

Tectonochemistry and p-t conditions of Ramgarh and Almora Gneisses from Askot Klippe,Kumaun Lesser Himalaya

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Acta Geologica Sinica(English Edition) 2019年第2期93卷 322-343页

作者： Biraja P.DAS Mallickarjvm joshi Ashutosh KUM AR centre of Advanced Study in Geology Institute of Science Banaras Hindu University

The chemical and petrological correlation of metamorphic nappes and klippes overlying the Proterozoic sedimentary units in the Kumaun Himalaya is still debated. The Ramgarh and Almora gneisses, not previously distinguished in the Askot Klippe, show distinct field, petrological and chemical signatures markedly similar to the tectonostratigraphic disposition of the Almora Nappe. A negative Eu anomaly in the Ramgarh granitic gneisses indicates lesser plagioclase fractionation while the Eu anomaly in the Almora pelitic gneisses is likely to have been controlled by feldspar crystallization in restites. During the anatexis at > 776°c temperature and >6.6 kbar pressure, the melt moved slightly away to its crystallization sites. The Rb/Sr ratio ?0.54 and Nb ?10 ppm is consistent with the granodioritic composition. The negative Sr anomaly in the underlying Ramgarh granitic gneisses indicates a distinct mantle derived source/plagioclase fractionation with a notable correspondence to other late orogenic granites, particularly the basement Ulleri gneisses from the Nepal Himalaya. Ramgarh gneisses plot in the late-and post-cOLG field. The Askot ensemble is likely to be the tectonometamorphically reworked basement, viz. the Ramgarh Group along with its metapelitic cover o f the Almora Group, together comprising southward thrust remnants of the leading edge of the Indian Plate that collided with Tibet during the Tertiary Himalayan orogeny.

关键词： geochemistry thermobarometry Almora gneiss Ramgarh gneiss Almora Nappe Askot Klippe

Optimization of Die Heating for Pultrusion Processes

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Optimization of Die Heating for Pultrusion Processes

基于离散滑模控制的通信网络拥塞控制(英文)

第十三届国际复合材料会议

作者： JianhuaLi Sunilc.joshi y.c.Lam School of Mechanical and Production Engineering Nanyang Technological University Singapore 639 798 School of Mechanical and Production Engineering Nanyang Technological University Singapore 639 798 School of Mechanical and Production Engineering Nanyang Technological University Singapore 639 798

＜正＞Pultmsion is one of several processes by which polymer composites can be fabricated. The degree and uniformity of cure of pultmded composites influence their mechanical properties. Die temperature is one of the key parameters that affect degree of cure （a） in pultmsion. Hitherto, no mathematical relationship （objective function） between die-heater temperatures and degree of cure that can be used to optimize curing of a pultmdate is available.

关键词： pultrusion cure finite element analysis optimization

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中国科学技术大学学报 2012年第7期42卷 540-545页

作者： Rutvij c joshi Vishvjit K Thakar AD帕特尔理工学院电气与计算机工程系古吉拉特邦New Vallabh Viayanagar市388121

最近30年来,离散滑模控制(DSMc)被加以研究.在现有离散滑模控制的文献中,不但有完善的理论,并且有应用的实例.计算机通信网络(涵盖有线和无线情形)的发展给控制专家提出了具有挑战性的问题.此类系统的响应很快,因此要求控制器必须能快... 详细信息

最近30年来,离散滑模控制(DSMc)被加以研究.在现有离散滑模控制的文献中,不但有完善的理论,并且有应用的实例.计算机通信网络(涵盖有线和无线情形)的发展给控制专家提出了具有挑战性的问题.此类系统的响应很快,因此要求控制器必须能快速反应.同时,此类系统中的数据包和路由采用固有的切换方式.因此,在该网络系统中采用与其固有切换类似的滑动模态控制成为一个有趣的问题.本文应用离散滑模控制方法来解决通信网络的拥塞控制问题.在过去几年中,许多反馈控制方法被用来解决通信网络的许多问题,如流量控制,拥塞控制和功率控制.本文提出了一种新的应用滑动模态控制来实现通信网络拥塞控制的方法.由于计算机通信网络处理的是数字数据且在本质上是离散的,因此其是一类离散时间系统,因而可应用离散滑模控制.在该系统中,比特率保持恒定不变,通过调整缓冲区的长度来控制拥塞.出于模拟与分析的目的,缓冲区的最大长度被设为250bit.本文展示了离散滑模控制能够实现通讯网络不同特性的控制.

关键词：拥塞控制离散滑模控制通信网络