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Journal of Semiconductors 2013年第3期34卷 12-16页

作者： V.K.Dwivedi p.srivastava G.Vijaya prakash Nanophotonics Laboratory Department of PhysicsIndian Institute of Technology DelhiHauz khasNew Delhi-110 016India Nanostech Laboratory Department of PhysicsIndian Institute of Technology DelhiHauz khasNew Delhi-110 016India Nanophotonics Laboratory Department of PhysicsIndian Institute of Technology DelhiHauz khasNew Delhi-110016India

The fabrication of zinc oxide(ZnO) from inexpensive solution-processing techniques,namely,electrochemical deposition and electrospinning were explored on various conducting and mesoporous semiconducting *** conditions were derived for template- and self-assisted nano/micro structures and composites. ZnO thin films were annealed at a fixed temperature under ambient conditions and characterised using physical and optical *** photocurrent response in the UV region shows a fast rise and double decay behaviour with a fast component followed by a slow oscillatory *** results were correlated with surface chemical analysis from X-ray photoelectron *** characterisation details reveal the importance of fabrication parameter optimisation for useful low-cost optoelectronic applications.

关键词： zinc oxide electrochemical deposition surface analysis X-ray photoelectron spectroscopy photocurrent response optoelectronic applications

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应用田口设计法探讨影响地毯压缩性能的因素

国际纺织导报 2018年第9期46卷 14-14页

作者： R.K.Verma A.Agarwal p.srivastava S.K.Giri 刘书惠(译) 孟粉叶(校) 印度地毯技术研究所(IICT) 印度不详

为满足客户对产品高品质与快速可靠的交付要求，新的加工制造技术正飞速发展，这也促进了新产品的开发与制造工艺的改进。地毯主要可分为机制地毯和手工地毯两类，机制地毯有时也称动力制造地毯。各种机制地毯通常可通过针刺与黏合技术... 详细信息

为满足客户对产品高品质与快速可靠的交付要求，新的加工制造技术正飞速发展，这也促进了新产品的开发与制造工艺的改进。地毯主要可分为机制地毯和手工地毯两类，机制地毯有时也称动力制造地毯。各种机制地毯通常可通过针刺与黏合技术制备。

关键词：手工地毯压缩性能设计法加工制造技术田口应用制造工艺机制

Implications of multipurpose tree leaf application on wheat productivity in dry tropics

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Journal of Forestry Research 2013年第4期24卷 777-782页

作者： Rajani srivastava K.p.Singh Department of Botany Banaras Hindu University

Leaves of multipurpose tree species （those providing more than one function or product of human use） can serve as sources of fer- tilizer for nutrient supply, especially nitrogen （N）. In this study chopped leaves of tropical tree species （5 N-fixing species, 5 non-N-fixing species and combinations of 5 N-fixing with a non-N-fixing species） were in- corporated in soil to evaluate its effects on wheat biological productivity （including grain yield, GyIELD） under dryland conditions. High quality leaves of N-fixing tree species （e.g. Dalbergia sissoo, Cassia fistula and prosopis cineraria） had lower carbon/nitrogen （C/N）, lignin/nitrogen （L^o/N）, polyphenol/nitrogen （ppt/N） and lignin＋polyphenol /nitrogen （L~＋ppL/N） ratios than low quality leaves of non-N-fixing species. Com- bination treatments had intermediate values of different parameters, Application of high quality leaves caused greater increases in wheat productivity and yield than other species.

关键词： multipurpose tree leaves chemical quality index grain yield,N-fixing species non-N fixing species Dryland agriculture

Water and nutrient management effects on water use and yield of drip irrigated citrus in vertisol under a sub-humid region

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Journal of Integrative Agriculture 2017年第5期16卷 1184-1194页

作者： p panigrahi A K srivastava ICAR(Indian Council of Agricultural Research)-Indian Institute of Water Management Bhubaneswar 751023India ICAR(Indian Council of Agricultural Research)-Central Citrus Research Institute Nagpur 440010India

Scarcity of water and nutrients in orchards are the major causes of low productivity and decline of citrus in tropics. With a hypothesis that the optimal amount of water and nutrients application through drip irrigation （DI） could save substantial irrigation and fertilizers comparative to that under traditional basin irrigation （BI） with band placement of fertilizer （BpF）, this study was conducted in citrus in vertisol of central India. Three DI regimes： I1, I2 and I3 scheduled at 50% class-A pan evaporation rate （Ep）, 75% Ep, and 100% Ep atong with three fertilizer doses： F1, F2 and F3 at 50% recommended dose of fertilizer （RDF, N：p2Os：K20=600 g：200 g：100 g）, 75% of RDF and 100% of RDF were applied to mandai＇in plants respectively. BI with band placement of fertilizer （BpF） at 100% RDF was taken for comparison. All the drip-fertigation treatments （except I1F1） produced higher plant growth and fruit yield, with better quality fruits compared with BI＋BpF. The highest fruit yield （16.39t ha^-1）, water use efficiency （3.9 kg m^-3） and fertilizer use efficiency （87.3 kg kg^-1） were observed in I2F2. The concentrations of N, K and Fe in leaves were significantly higher in I2F2 compared to other treatments. The leaf photosynthesis, stomatal conductance （G） and transpiration were the highest in I3F3. However, leaf water use efficiency （LWUE, photosynthesis/transpiration） was the highest in I2F2. The overall results of this study demonstrated that the application of optimum quantity of water and fertilizers （I2F2） through DI could be a productive and water efficient option in citrus production in vertisol.

关键词： drip irrigation fertigation citrus fruit yield fruit quality economics of production

Synthesis and enhanced photoluminescence properties of red emitting divalent ion(Ca^(2+))doped Eu:Y_(2)O_(3)nanophosphors for optoelectronic applications

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Journal of Rare Earths 2022年第8期40卷 1187-1198页

作者： Arpita Dwivedi Monika srivastava Ankur Dwivedi Amit srivastava Anurag Mishra S.K.srivastava Department of physics Institute of ScienceBanaras Hindu University(BHU)Varanasi221005India School of Materials Science and Technology Indian Institute of Technology(BHU)Varanasi221005India Department of Mining Engineering Indian Institute of Technology(BHU)Varanasi221005India Department of physics TDpG College VBS Purvanchal UniversityJaunpur222001India

This work presents the synthesis of Y_(2)O_(3):Eu^(3+),χCa^(2+)(χ=0 mol%,1 mol%,3 mol%,5 mol%,7 mol%,9 mol%,11 mol%)nanophosphors with enhanced photoluminescence properties through a facile solution combustion method for optoelectronic,display,and lighting *** X-ray diffraction(XRD)patterns of the proposed nanophosphor reveal its structural properties and crystalline *** transmission electron microscope(TEM)results confirm the change in the shape of the particle and aggregation of particles after co-doping with Ca^(2+).Fourier transform infrared spectroscopy(FTIR)and Raman vibrations also confirm the presence of Y-O vibration and subsequently explain the crystalline nature,structural properties,and purity of the *** the synthesized nanophosphors samples emit intense red emission at 613 nm(~5D_(0)→~7 F_(2))under excitation with 235,394 and 466 nm wavelengths of Eu^(3+)*** photoluminescence(pL)emission spectra excited with 235 nm illustrate the highest emission peak with two other emission peaks excited with 466 and 394 nm that is 1.4 times higher than 466 nm and 1.9 times enhanced by 394 nm wavelength,*** emission intensity of Y_(2)O_(3):Eu^(3+),χCa^(2+)(5 mol%)is increased 8-fold as compared to Eu:Y_(2)O_(3).Doping with Ca^(2+)ions enhances the emission intensity of Eu:Y_(2)O_(3)nanopho sphors due to an increase in energy transfer in Ca^(2+)→Eu^(3+)through asymmetry in the crystal field and by introduction of radiative defect centers through oxygen vacancies in the yttria *** is also observed that the optical band gap and the lifetime of the~5D_(0)level of Eu^(3+)ions in Y_(2)O_(3):Eu^(3+),xCa^(2+)nanophosphor sample gets changed with a doping conce ntration of Ca^(2+)*** also reveals high thermal stability and quantum yield as estimating activation energy of 0.25 eV and 81%,***,CCT,and color purity values(>98%)show an improved red-emitting nanophosphor in the warm region of light,which m

关键词： Red emission photoluminescence(pL) Y_(2)O_(3):Eu^(3+),xCa^(2+) Rare earths Nanophosphors LEDs

RSpO2 as Wnt signaling enabler: Important roles in cancer development and therapeutic opportunities

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Genes & Diseases 2024年第2期11卷 788-806页

作者： Ankit srivastava Deeksha Rikhari Sameer srivastava Department of Biotechnology Motilal Nehru National Institute of TechnologyAllahabadUttar Pradesh 211004India

R-spondins are secretory proteins localized in the endoplasmic reticulum and Golgi bodies and are processed through the secretory *** the R-spondin family,RSpO2 has emanated as a novel regulator of Wnt signaling,which has now been acknowledged in numerous in vitro and in vivo *** is an abnormal growth of cells that proliferates and spreads uncontrollably due to the accumulation of genetic and epigenetic factors that constitutively activate Wnt signaling in various types of *** cancer (CRC) begins when cells in the colon and rectum follow an indefinite pattern of division due to aberrant Wnt activation as one of the key ***-long progress in research on R-spondins has demonstrated their oncogenic function in distinct cancer types,particularly *** a critical regulator of the Wnt pathway,it modulates several phenotypes of cells,such as cell proliferation,invasion,migration,and cancer stem cell ***,RSpO mutations,gene rearrangements,fusions,copy number alterations,and altered gene expression have also been identified in a variety of cancers,including *** this review,we addressed the recent updates regarding the recurrently altered R-spondins with special emphasis on the RSpO2 gene and its involvement in potentiating Wnt signaling in *** addition to the compelling physiological and biological roles in cellular fate and regulation,we propose that RSpO2 would be valuable as a potential biomarker for prognostic,diagnostic,and therapeutic use in CRC.

关键词： CRC Gene fusion R-Spondins RSpO2 Therapeutics Wnt signaling

A near infrared optical reflector using one-dimensional photonic crystal structure containing chalcogenide glasses

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Optoelectronics Letters 2010年第6期6卷 406-411页

作者： Sanjeev K.srivastava S K Awasthi S K srivastava S.p.Ojha Department of physics Amity Institute of Applied SciencesAmity University Department of physics Jaypee Institute of Information TechnologyDeemed University Department of physics Mahila Maha VidyalayBanaras Hindu University Department of Applied physics Institute of TechnologyBanaras Hindu University

The reflectivity of one-dimensional chalcogenide photonic crystal(CGpC) structure with the first order reflection band in near infrared(NIR) region is theoretically ***-Se and Ge-S chalcogenide glasses are used as high and low refractive index layers respectively,because these materials have zero absorption in NIR *** transfer matrix method(TMM) is employed to calculate the reflective spectra of the proposed *** theoretical results of reflective spectra of bulk chalcogenide materials with the composition of Sb40Se60 and Ge30S70 for 4,8,12 and 15 layers and thicknesses of 117 nm and 183 nm respectively,at normal incidence,are close agreement with the experimental ***,by increasing the number of layers of Sb40Se60 and Ge30S70,the reflection bands can be enhanced in the wider range of the NIR region for the polarization at different angles and thus the broadband omnidirectional reflector can be designed.

关键词：一维光子晶体晶体结构硫系玻璃近红外光反射镜红外区域反射光谱计算结果

Biologics in the management of pediatric inflammatory bowel disease:When and what to choose

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World Journal of Clinical pediatrics 2025年第1期14卷 21-45页

作者： Arghya Samanta Anshu srivastava Department of pediatric Gastroenterology Sanjay Gandhi Postgraduate Institute of Medical SciencesLucknow 226014Uttar PradeshIndia

pediatric inflammatory bowel disease(pIBD)is a chronic inflammatory disorder of the gastrointestinal tract,with rising global incidence and *** the past two decades,biologics have added to the therapeutic armamentarium and revolutionized the approach to treatment of inflammatory bowel *** available biologics include monoclonal antibodies which target inflammatory cytokines(anti-tumor necrosis factor alpha,anti-interleukin 12/23)or recruitment of leucocytes to the gastrointestinal tract(anti-alpha4beta7 integrin)and small molecules(Janus kinase inhibitors,sphingosine 1-phosphate-inhibitors)which modify the proinflammatory *** their potential disease-modifying ability,recent pediatric guidelines from the West have advocated upfront use of biologics in appropriate clinical scenarios as a top-down approach rather than the conventional step-up *** real-world studies are available regarding the clinical efficacy of biologics in pIBD,there is paucity of long-term outcome and safety data in ***,little information is available about the best approach in the newly industrialized-developing countries where pIBD is rising but at the same time,infections are prevalent and resources are *** this review,we summarize the efficacy and safety profile of biologics and small molecule drugs and discuss the challenges in the management of pIBD,especially in the developing world,and future directions.

关键词： Biologics Children Inflammatory bowel disease Therapeutic drug monitoring Dual biologic

Largest Ediacaran discs from the Jodhpur Sandstone, Marwar Supergroup, India: Their palaeobiological significance

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Geoscience Frontiers 2014年第2期5卷 183-191页

作者： purnima srivastava Centre of Advanced Study in Geology Lucknow University

Ediacaran discs from the Jodhpur Sandstone of the Marwar Supergroup, Rajasthan, exhibit a wide size ranging from a few millimetres to 75 cm in diameter. Exceptionally large size of the discs in these rocks represent the largest reported so far from any Ediacaran assemblage. Although, larger medu-soid discs have been reported from USA, they are from the middle Cambrian and even younger rocks. presence of microbial mats and weed-like structures with well preserved hold fasts and horizontal rhizome-like structures in association with some of these large-sized discs support their animal affinity, which probably feed on this weed-like vegetations. This association also supports their benthic habitat. Unlike the general trend of sudden increase in size of organisms in Ediacaran period and further decrease in size during Cambrian, these discs continued increasing in size in Cambrian also.

关键词： Ediacaran discs Jodhpur Sandstone Marwar Supergroup Rajasthan India

High-yield synthesis and liquid-exfoliation of two- dimensional belt-like hafnium disulphide

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Nano Research 2018年第1期11卷 343-353页

作者： Harneet Kaur Sandeep Yadav Avanish K. srivastava Nidhi Singh Shyama Rath Jorg J. Schneider Om p. Sinha Ritu srivastava National physical Laboratory Council of Scientific and Industrial Research Dr. K. S. Krishnan Road New Delhi I I O012 India Academy of Scientific and Innovative Research NPL New Delhi 110012 India Technische Universitat Darmstadt Eduard-ZintMnstitut f~r Anorganische und Physikalische Chemie 12 105 117 Alarich-Weiss-Str 12 64287 Darmstadt Germany Departmentofphysics andAstrophysics University of Delhi Delhi 110007 India Amity Institute of Nanotechnology Amity University UP Sector 125 Noida Uttar Pradesh 201313 India

producing environmentally stable monolayers and few-layers of hafnium disulphide （HfS2） with a high yield to reveal its unlocked electronic and optoelectronic applications is still a challenge. HfS2 is a layered two-dimensional material of group-IV transition metal dichalcogenides. For the first time, we demonstrate a simple and cost-effective method to grow layered belt-like nanocrystals of HfS2 with a notably large interlayer spacing followed by their chemical exfoliation. Various microscopic and spectroscopic techniques confirm that these as-grown crystals exfoliate into single or multiple layers in a few minutes using solvent assisted ultrasonification method in N-cyclohexyl-2- pyrrolidone. The exfoliated nanosheets of HfS2 exhibit an indirect bandgap of 1.3 eV with high stability against surface degradation. Furthermore, we demonstrate that these nanosheets hold potential for electronic applications by fabricating a field-effect transistor based on few-layered HfS2, exhibiting a field-effect mobility of 0.95 cm2/（V.s） with a high on/off current modulation ratio of 10,000 in ambient conditions. The method is scalable and has a potential significance for both academic and industrial purposes.

关键词： two-dimensionalmaterials hafnium disulphide nano-crystals liquid-phase exfoliation environment-stabili~ field-effect transistor