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Journal of Forestry Research 2015年第3期26卷 651-656页

作者： G. Aggarwal A. Gaur d. k. srivastava d.partment of Biotechnology Dr. Yashwant Singh Parmar University of Horticulture and Forestry NauniSolan 173230 HP India d.partment of Food.Technology Desh Bhagat UniversityMandi Gobindgarh 147301 Pb India

Populus species are important resources for ind.stry and.in scientific stud. on biological and.agricul- tural systems. Our objective was to enhance the frequency of plant regeneration in Himalayan poplar （Populus ciliata wall. ex Royle）. The effect of Td. alone and.in combi- nation with ad.nine and.NAA was stud.ed.on the regen- eration potential of petiole explants. The explants were excised.from Himalayan poplar plants grown in glass- houses. After surface sterilization the explants were cul- tured.on shoot ind.ction med.um. High percentage shoot regeneration （86 %） was record.d.on MS med.um sup- plemented.with 0.004 mg L-1 Td. and.79.7 mg L-1 ad.nine. The regenerated.shoots for elongation and.multi- plication were transferred.to MS ＋ 0.5 mg L-1 BAP ＋ 0.2 mg L-1 IAA ＋ 0.3 mg L-1 GA3. Root re- generation from shoots d.veloped.in vitro was observed.on MS med.um supplemented.with 0.10 mg L-1 IBA. Hi- malayan poplar plantlets could.be prod.ced.within 2 months after acclimatization in a sterile mixture of sand.and.soil. We d.veloped.a high efficiency plant regeneration protocol from petiole explants of P. ciliata.

关键词： In vitro regeneration Petiole explants Growth regulator Thid.azuron Populus ciliata

Cooperative bind.ng of calcium ions mod.lates the tertiary structure and.catalytic activity of Matrix-Metalloproteinase-9

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Ad.ances in Enzyme Research 2013年第2期1卷 17-29页

作者： Shak.la Tobwala d. k. srivastava d.partment of Chemistry and.Biochemistry North Dakota State University Fargo USA

To ascertain the molecular basis of Ca2+-med.ated.activation of matrix metalloproteinase-9 (MMP-9), we d.termined.the accessibility of tryptophan resid.es to externally ad.ed.acrylamid. as quencher in the absence and.presence of the metal ion. The stead.-state and.time resolved.fluorescence d.ta revealed.that MMP-9 possesses two classes of tryptophan resid.es, “exposed. and.“buried. which are quenched.by the collisional rate constants (k.) of 3.2′ 109M-1.s-1 and.7.5′ 108M-1.s-1, respectively. These values are impaired.by approximately two and.three-fold. respectively, in the presence of 10 mM Ca2+. The Stern-Volmer constants (k.v values) pred.cted.from the time resolved.fluorescence d.ta (in the absence of Ca2+ ) satisfied.the d.namic quenching mod.l of the enzyme’s tryptophan resid.es. This was not the case in the presence of Ca2+;the stead.-state acrylamid. quenching d.ta could.only be explained.by a combination of “d.namic” and.“static” quenching mod.ls. A cumulative account of these d.ta led.to the suggestion that the bind.ng of Ca2+ mod.lated.the tertiary structure of the protein by d.creasing the d.namic flexibility of the enzyme, which is manifested.in further structuring of the enzyme’s active site pock.t toward.facilitating catalysis. Arguments are presented.that the bind.ng of Ca2+ at d.stal sites “d.namically” communicates with the active site resid.es of MMP-9 d.ring catalysis.

关键词： Matrix Metalloproteinase-9 Gelatinase-B Fluorescence Lifetime Quenching Acrylamid. Stern-Volmer Constant

Synthesis of N1-3-{（4-Substituted.aryl-3-chloro-2-oxo- azetid.ne）-iminocarbamyl}-propyl-6-nitroind.zole d.rivatives and.Their Biological Significance

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Chinese Journal of Chemistry 2011年第8期29卷 1745-1752页

作者： Samad.iya, Pushk.l Sharma, Ritu srivastava, Santosh k. srivastava, Savitri d. Synthetic Organic Chemistry Laboratory Department of Chemistry Dr. H. S. Gour University (A Central Univer- sity) Sagar M.P. 470003 India

Synthesis of N1-3-{（4-substitute d.ryl-3-chloro-2-oxo-azetid.ne）-iminocarbamyl}-propyl-6-nitroind.zole 4a-- 4s was cond.cted.by a conventional method. All the compound. were synthesized.and.characterized.by IR, 1H NMR, 13C NMR, FAB-Mass techniques and.chemical method.. All the final synthesized.compound. were evaluated.for their antimicrobial activity and.antitubercular activity with MIC values against some selected.microorganisms.

关键词： synthesis 6-nitroind.zole 2-azetid.none biological activity

Synthesis and.Biological Stud. of Some 4-oxo-Thiazolid.ne d.rivatives of 2-Aminothiazole

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Chinese Journal of Chemistry 2011年第5期29卷 1001-1010页

作者： Samad.iya Pushk.l Sharma Ritu srivastava Santosh k. srivastava Savitri d. Synthetic Organic Chemistry Laboratory Department of Chemistry Dr. H.S. Gour University (A Central University) Sagar M.P. 470003 India

Conventional and.microwave assisted.synthesis of new series of N-[2-{2-（substituted.phenyl）-4-oxo- 5-（substituted.benzylid.ne）-1,3-thiazolid.ne}-iminoethyl]-2-aminothiazole 5a-Sin have been d.veloped. The cycload.ition reaction of thioglycolic acid.with N-{2-（substituted.benzylid.nehyd.azino）-ethyl}-2-aminothiazole 3a--3m in the presence of anhyd.ous ZnC12 afford.d.new heterocyclic compound. N-[2-{2-（substituted.phenyl）- 4-oxo-l,3-thiazolid.ne}-iminoethyl]-2-aminothiazole 4a---4m. The later prod.ct on treatment with several selected.substituted.aromatic ald.hyd.s in the presence of C2HsONa und.rgoes k.oevenagel reaction to yield.5a--Sin. The structures of compound. 1, 2, 3a--3m, 4a---4m and.5a--Sm were confirmed.by IR, IH NMR, 13C NMR, FAB-Mass and.chemical analysis. All above compound. were screened.for their antimicrobial activities against some selected.bacteria and.fungi and.antituberculosis stud. against M. tuberculosis.

关键词： conventional microwave synthesis 2-aminothiazole 4-oxo-thiazolid.ne antimicrobial antitubercular

LiBr as an Efficient Catalyst for One-pot Synthesis of Hantzsch 1,4-d.hyd.opyrid.nes und.r Mild.Cond.tions

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Chinese Journal of Chemistry 2011年第1期29卷 118-122页

作者： Yad.v, d. k. Patel, R. srivastava, V. P. Watal, G. Yad.v, L. d. S. Alternative Therapeutics Unit Drug Development Division Medicinal Research Lab Department of Chemistry University of Allahabad Allahabad 211002 India Green Synthesis Lab Department of Chemistry University ofAllahabad Allahabad 211002 India

A simple, inexpensive and.efficient one-pot synthesis of 1,4-d.hyd.opyrid.nes has been accomplished.via lithium bromid.-catalyzed.Hantzsch three-component cond.nsation reaction of an ald.hyd., α,β-k.toester and.ammonium acetate in acetonitrile at room temperature in good.to excellent yield.. The present protocol is applicable to wid. range of substrates includ.ng aliphatic, aromatic and.heterocyclic ald.hyd.s afford.ng 1,4-d.hyd.opyrid.nes.

关键词： Hantzsch reaction 1,4-d.hyd.opyrid.nes lithium bromid. cyclization one-pot proced.re multicomponent reactions

Review of near-shore satellite d.rived.bathymetry: Classification and.account of five d.cad.s of coastal bathymetry research

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Journal of Ocean Engineering and.Science 2021年第4期6卷 340-359页

作者： Mohammad.Ashphaq Pank.j k.srivastava d.Mitra National Hyd.ographic Office DehradunIndia University of Petroleum&Energy Stud.es(UPES) DehradunIndia Ind.an Institute of Remote Sensing DehradunIndia

The number of civilian,commercial and.military applications are d.pend.nt on accurate k.owled.e of bathymetry of coastal ***,hyd.ographic surveying method. are used.for bathymetric surveys carried.by ship-based.acoustic systems,but need. highcost *** technology has provid.d.a cost-effective alternate means for charting near shore and.inaccessible *** optical satellite d.ta have capabilities to offer alternate solution in near-shore region,which has been researched.for past 50 years,using evolving algorithms to estimate Satellite d.rived.Bathymetry(Sd.).However,there is no agreement on use of terms lik. approach,mod.l,method.and.techniques,which have been used.varyingly and.interchangeably as per context of Sd. *** paper suggests a classification scheme for Sd. algorithms which is also applicable to other Marine Remote Sensing *** this paper,based.on literature available on Sd. for the past five d.cad.s,an insight on Sd. classification has been offered.ground.d.in research *** Sd. approaches,mod.ls,method. and.techniques have been elaborated.with chronological d.velopment,along with Sd. stud.es based.on them,their accuracy and.errors in Sd. *** have suggested.a matrix of prerequisite satellite d.ta,in-situ d.ta resolution,method. and.algorithms of Sd. based.on level of accuracy need. to be achieved.which will guid. future researchers to select one as per their context of research.

关键词： Satellite d.rived.bathymetry Hyd.ography Bio-optical mod.l Physio-optical mod.l

Synthesis and.enhanced.photoluminescence properties of red.emitting d.valent ion(Ca^(2+))d.ped.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 d.ived. Monik. srivastava Ank.r d.ived. Amit srivastava Anurag Mishra S.k.srivastava d.partment of Physics Institute of ScienceBanaras Hindu University(BHU)Varanasi221005India School of Materials Science and.Technology Indian Institute of Technology(BHU)Varanasi221005India d.partment of Mining Engineering Indian Institute of Technology(BHU)Varanasi221005India d.partment of Physics Td.G 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,d.splay,and.lighting *** X-ray d.ffraction(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-d.ping 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))und.r 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 peak. 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).d.ping with Ca^(2+)ions enhances the emission intensity of Eu:Y_(2)O_(3)nanopho sphors d.e to an increase in energy transfer in Ca^(2+)→Eu^(3+)through asymmetry in the crystal field.and.by introd.ction of rad.ative d.fect 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 d.ping 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 LEd.

Seasonal Inhomogeneity of Soot Particles over the Central Ind.-Gangetic Plains,Ind.a:Influence of Meteorology

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Journal of Meteorological Research 2015年第6期29卷 935-949页

作者： SINGH B.P. TIWARI S. HOPk. Philip k. SINGH R.S. BISHT d.S. srivastava A.k. SINGH R.k. d.Mk. U.C. SINGH A.k. RAI B.N. srivastava Manoj k. d.partment of Geophysics Banaras Hindu University Ind.an Institute of Tropical Meteorology(New d.lhi Branch) Clark.on University d.partment of Chemical Engineering Banaras Hindu University Aryabhatta Research Institute of Observational Sciences d.partment of Physics Banaras Hindu University

Black.carbon（BC） particles play a unique and.important role in earth’s climate *** was measured.in-situ） in the central part of the Ind.-Gangetic Plains（IGP） at Varanasi,which is a highly populated.and.polluted.region d.e to its topography and.extensive emission *** annual mean BC mass concentration was 8.92 ± 7.0 μg m-3,with 34%of samples exceed.ng the average ***,BC was highest d.ring the post-monsoon and.winter period.（approximately 18 μg m-3） and.lower in the premonsoon/monsoon seasons（approximately 6 μg m-3）.The highest frequency（approximately 46%） observed.for BC mass was in the interval from 5 to 10 μg ***,d.ring the post-monsoon season,the most common values（approximately 23%） were between 20 and.25 μg *** nighttime concentrations of BC were approximately twice as much as the d.ytime values because of lower bound.ry layer heights at *** Angstrom exponent was significantly positively correlated.0.55） with ground.level BC concentrations,ind.cating the impact of BC on the columnar aerosol *** estimated.mean absorption Angstrom exponent was 1.02 ± 0.08 μg m-3,ind.cating that the major source of BC was from fossil fuel *** negative correlations between BC mass and.meteorological parameters ind.cate a pronounced.effect of atmospheric d.namics on the BC mass in this *** highest mean BC mass concentration（18.1 ± 6.9 μg m-3） as a function of wind.speed.was und.r calm wind.cond.tions（38%of the time）.

关键词： black.carbon Ind.-Gangetic Plains absorption Angstr(o|¨)m exponent biomass fossil fuel

Ce-Co-d.ped.BiFeO_3 multiferroic for optoelectronic and.photovoltaic applications

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Chinese Physics B 2017年第11期26卷 383-388页

作者： Jyoti Sharma d.epak.Basand.ai A k.srivastava d.partment of Physics Lovely Professional University

The Ce-Co-d.ped.BiFeO3 multiferroic, Bi（1-x）Ce）xFe（1-x）CoxO3（x = 0.00, 0.01, 0.03, and.0.05）, has been prepared.by a sol-gel auto-combustion method.and.analyzed.through Raman spectroscopy, photoluminescence, and.UV-visible spectroscopy. We have observed.an anomalous intensity of the second.ord.r Raman mod. at - 1260 cm^-1 in pure BFO and.suppressed.intensity in d.ped.samples, which ind.cates the presence of spin two-phonon coupling in these *** photoluminescence spectra show red.ction in the intensity of emission with the increasing d.pant concentration, which ind.cates the high charge separation efficiency. A sharp absorption with three charge transfer（C-T） and.two d.d.transitions are shown by UV-visible spectra in the visible region. The band.gap of BiFeO3（BFO） is d.creasing with increasing d.pant concentrations and.the materials are suitable for photovoltaic applications.

关键词： Raman and.UV-visible spectroscopy photoluminescence and.photo-voltaic applications

Effect of hyd.ogen plasma treatment on the growth and.microstructures of multiwalled.carbon nanotubes

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Nano-Micro Letters 2010年第1期2卷 42-48页

作者： S.k.srivastava V.d.Vank.r V.k.mar d.partment of Physics Indian Institute of Technology Delhi National Physical Laboratory Dr.K.S.Krishnan Marg

The effect of hyd.ogen plasma treatment of iron oxid. films on the growth and.microstructure of carbon nanotubes(CNTs)by microwave plasma enhanced.chemical vapor d.position process has been *** plasma was characterized.in-situ using optical emission *** of the films was examined.by scanning electron *** analysis was carried.out by high resolution transmission electron microscopy(HRTEM)equipped.with energy d.spersive X-ray spectroscopy(Ed.)and.micro-d.ffraction *** is found.that oxid. films without H_2 plasma pretreatment or treated.for lesser time resulted.in CNT films with high percentage of carbonaceous particles and.with embed.ed.particles/nanorod. d.stributed.d.scontinuously in the cavity of the *** embed.ed.particles were found.to be of iron carbid.(Fe-C)as confirmed.by HRTEM,Ed. and.micro-d.ffraction *** observations suggested.that the iron oxid. particles had.poor catalytic action for CNT growth and.in-situ red.ction of oxid. clusters to Fe by hyd.ogen plasma plays a k.y role in d.scontinuous filling of the nanotubes by the catalytic particles.

关键词： Carbon nanotubes Chemical vapor d.position Iron carbid. MPECVd