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地中海及其邻区的上地幔速度结构

地球物理学进展 1992年第1期7卷 105-105页

作者： v.g.krishna 柯忍

本文仔细地分析了深达500km的229个深震的P波和S波走时资料,取得了地中海及其邻区的上地幔速度结构.用Kaila(1969)分析法得到卡拉布里亚孤—第勒尼安海、西地中海—南西班牙、巴尔干半岛的西缘和东缘以及东喀尔巴阡山脉的vrancea区的中... 详细信息

本文仔细地分析了深达500km的229个深震的P波和S波走时资料,取得了地中海及其邻区的上地幔速度结构.用Kaila(1969)分析法得到卡拉布里亚孤—第勒尼安海、西地中海—南西班牙、巴尔干半岛的西缘和东缘以及东喀尔巴阡山脉的vrancea区的中、深源地震区的“震源深度上”的P波和S波速度.显示出直到150km深度的地段,其横向速度变化约为3%一4%.巴尔干边缘的尸波速度为最高.在卡拉布里亚孤一第勒尼安海深震区,p波速度由40 km深度上8.01 km/s增加到2,0 km深度上的8.14 km/5.尸波速度从具变化率为0,0055一,的210 km较深部起迅速地增加,到500 km深度上.达到9.62 km/5.该区的S波速度由40k。深度上的458 km/s增加到400 km深度上的4.73 km/:,没有任何关于快速的速度增加带的象征.然而,发现了卡拉布里亚孤一第勒尼安海深震区的S波速度比由面波频散研究导出的邻区的上地慢顶部150一200 km区段的平均S波速度4.34 km/s高出约6%.与此类似,西地中海和巴尔干边缘的中源地震区,其S波速度比邻区上地慢相应的平均值高约5%.这些差异本质上是因为存在一条轮廓清晰的扩展到中欧大部地区的次盖层(sub一lid))低S波速通道引起的.本文确定的卡拉布里亚弧一第勒尼安海深震区的尸波速度模型显然与EKw的p波速度模型(England等,1 077)和MR的速度模型(Mager一Rosa和Mue]ler.1 973)+分一致,这两个模型适用于南一中欧下方的上地慢区域、把南一中欧的尸波速度模型,包括本文提出的模型,与适合于东欧地台下方的上地慢p波速度模型,即sNF(Hurtig等,1979),KCA(King和Caxeagnile,197e)和M^(Masse和Alexander,1974)模型相比较,揭示出这两区的上地慢具有强烈的横向速度不均匀性.南一中欧的速度比东欧地台的速度约低5%,这种情况到至少250 km的深度上都存在.这些结果与stromeyer(1 978)给出的欧洲温度一深度函数一致,Stromcyer(1 978)指出中欧的这些深度上的温度比东欧地台的高400一500℃.本文确定的卡拉布里亚孤一第勒尼安海深震区,从40一400 km深度,其S波速度(4,6一4.7 km/s)几乎不变.也是与所预计的中欧下方的邻近上地慢区具较高温度相一致.在本研究中,尸波和S波速度模型,直到深达500 km都未发现“400 km间断”,这可能是因为在南一中欧,它在520一540 km这个比较大的深度上,而其它几个模型给出,在东欧地台区它在380一420 km的深度上,比较之下相对较浅.另一方面,210一500 km深度上的高尸波速度梯度可以说明不存在“明显的”400 km间断。

关键词：波速度速度模型速度结构上地幔横向速度变化速度比第勒尼安海地台频散面波

A glycine-rich nuclear effector vdCE51 of verticillium dahliae suppresses plant immune responses by inhibiting the accumulation of ghTRXH2

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The Crop Journal 2024年第4期12卷 1137-1149页

作者： Chi Li Yingqi Huang Wenjing Shang Jieyin Chen Steven J.Klosterman krishna v.Subbarao Jun Qin Xiaoping Hu State Key Laboratory of Crop Stress Resistance and High-Efficiency Production Key Laboratory of Plant Protection Resources and Pest Management of Ministry of EducationKey Laboratory of Integrated Pest Management on the Loess Plateau of Ministry of Agriculture and Rural AffairsCollege of Plant ProtectionNorthwest A&F UniversityYangling 712100ShaanxiChina State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193China Western Agricultural Research Center Chinese Academy of Agricultural SciencesChangji 831100XinjiangChina Agricultural Research Service United States Department of AgricultureSalinasCA 93905USA Department of Plant Pathology University of CaliforniaDavisc/o United States Agricultural Research StationSalinasCA 93905USA

verticillium dahliae is an important soil-borne fungal pathogen that causes great yield losses in many cash *** of this fungus are known to regulate plant immunity but the mechanism much remains unclear.A glycine-rich nuclear effector,vdCE51,was able to suppress immune responses in tobacco against Botrytis cinerea and Sclerotinia *** effector was a required factor for full virulence of ***,and its nuclear localization was a requisite for suppressing plant *** thioredoxin ghTRXH2,identified as a positive regulator of plant immunity,was a host target of *** findings show a virulence regulating mechanism whereby the secreted nuclear effector vdCE51 interferes with the transcription of PR genes,and the SA signaling pathway by inhibiting the accumulation of ghTRXH2,thus suppressing plant immunity.

关键词： verticillium dahliae Plant immunity Effector Thioredoxin

由地震折射的走时和振幅确定的美国西部地壳速度模型

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地球物理学进展 1988年第Z1期 7-7页

作者： v.g.krishna ,孙克忠

由走时和振幅解释地壳震相,取得美国西部新的地壳P波速度—深度函数,其地震折射剖面为犹他州Delta以西的剖面和科罗拉多州Lamar以西的剖面,前者位于盆地山脉省北部地区,后者位于落基山脉南部great Plains地区。新地壳结构不只证实了较... 详细信息

由走时和振幅解释地壳震相,取得美国西部新的地壳P波速度—深度函数,其地震折射剖面为犹他州Delta以西的剖面和科罗拉多州Lamar以西的剖面,前者位于盆地山脉省北部地区,后者位于落基山脉南部great Plains地区。新地壳结构不只证实了较早推断的地壳结构的主要特点,而且得到更为详细的地壳速度变化范围。盆地山脉省的地壳特点是地壳

关键词：地震折射盆地山脉地质构造地壳结构低速层波速度美国西部

Paleo-Mesoarchean sedimentary record in the Dharwar Craton,India:Implications for Archean ocean oxygenation

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geoscience Frontiers 2024年第1期15卷 126-154页

作者： g.Harshitha C.Manikyamba M.Santosh Cheng-Xue Yang A.Keshav krishna v.v.Sesha Sai I.Panduranga Reddy CSIR-National geophysical Research Institute(NgRI) Uppal RoadHyderabad 500007India Department of geology Osmania UniversityHyderabad 500007India School of Earth Science and Resources China University of GeosciencesBeijing 100083China Department of Earth Science University of AdelaideAdelaide SA5005Australia Yonsei Frontier Lab Yonsei UniversitySeoul 03722Republic of Korea geological Survey of India State UnitNagpurIndia

The early Archean oceans were marked by significant redox changes which have subsequently shaped the Earth’s *** chemical sediments of banded Iron and Manganese formations provide important geochemical proxies for these historical shifts in the redox conditions and to trace the ancient sedimentation patterns and *** this study,we investigate the proto-ore of the Archean Mn-formations of the Sandur,Chitradurga and Shimoga greenstone belts of Dharwar Craton of southern Peninsular India,which is geochemically characterised as quartz arenites,Mn-arenites,Fe-arenites,Mn-argillites and *** geochemical systematics suggest their deposition in shallow to deeper shelf in the Archean *** detrital zircon U-Pb systematics of Mn arenites and argillites indicate their maximum depositional age of 3230±52 Ma representing the oldest onset of sedimentation during the Paleo-Mesoarchean timeframe in the Chitradurga group of Dharwar *** detrital influx proxies suggest variations in sedimentation rates associated with the Archean transgressive-regressive cycles and fluctuating hydrodynamic conditions,together reflecting an increasing trend in the contributions of recycled sediment from Sandur to Chitradurga and Shimoga greenstone *** available detrital zircon ages of the Mn arenites and argillites from these greenstone belts indicate a~600 Ma prolonged period of Mn deposition for which high-T hydrothermal fluids from Archean mid-oceanic ridges supplied the *** trace element compositions of the concordant detrital zircons suggest 3.3-3.1 ga Dharwar basement TTg/granitoid source which is corroborated by the zircon crystallization temperatures of 690-820℃.The source-normalisedα-dose rates of the detrital zircons signify greater degrees of sediment transport and multi-cycle nature which correspond to the earliest episode of crustal growth in the Indian sub-continent associated with the Mesoarchean Ur supercontinent.T

关键词： Mn-arenites-argillites Dharwar Craton Zircon U-Pb geochronology Passive margin sediments Ocean oxygenation

Nano-engineered catalysts for high-performance oxygen reduction reaction

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Chinese Chemical Letters 2024年第10期35卷 510-516页

作者： Kunsong Hu Yulong Zhang Jiayi Zhu Jinhua Mai gang Liu Manoj krishna Sugumar Xinhua Liu Feng Zhan Rui Tan School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China Energy Innovation Centre Warwick Manufacture GroupUniversity of WarwickCoventry CV47ALUnited Kingdom School of Transportation Science and Engineering Beihang UniversityBeijing 100191China IDTECH(Suzhou)Co. Ltd.Suzhou 215217China College of Mechatronical and Electrical Engineering Hebei Agricultural UniversityBaoding 071001China

The efficient energy conversion of fuel cells is greatly constrained by the slow oxygen reduction reac tion(ORR)kinetics,which necessitates the use of highly active metal catalysts such as platinum(Pt).The critical challenge limiting large-scale usage of Pt is the capital cost that can be addressed through a pro totypical approach by embedding metal nanoparticles(NPs),e.g.,Pt NPs,in the conductive framework However,previously reported embedding approaches are sophisticated and suffer from limited yields leading to higher chemical process costs and remaining distant from commercial ***,we re port a facile,cost-effective and time-efficient structural tuning approach to synthesizing ultrafine Pt NP impregnated within a conductive and highly porous carbon framework via a microwave-assisted polyo reduction *** NPs with a uniform size of~2.27 nm can be successfully integrated within the pore of the carbon framework,enabling homogeneous *** from these highly dispersed and ultrafine Pt NPs,the electrochemical surface area(ECSA)is improved to 142.98 m^(2)/gPt,2.25 times highe than that of the commercial counterpart(63.52 m^(2)/gPt).Furthermore,our structurally optimized catalys composite features a remarkably catalytic activity with a high half-wave potential(E_(1/2))of 0.895 v and an improved mass activity(MA)of 0.2289 A/mgPt,2.39-fold improvement compared to the commercia *** addition,orthogonal experiments were designed to identify the key process parameter for fabricating Pt/C catalysts,offering insights for scaled-up and industrial production.

关键词： Fuel cells Oxygenreductionreaction Structural engineering Microwave method Ultrafine nanoparticles

Microstructure and mechanical properties of similar and dissimilar metal gas tungsten constricted arc welds:Maraging steel to 13-8 Mo stainless steel

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Defence Technology（防务技术） 2019年第1期15卷 111-121页

作者： C.v.S.Murthy A.gopala krishna g.M.Reddy Defence Research and Development Laboratory Jawaharlal Nehru Technological University Defence Metallurgical Research Laboratory

Maraging steel (250) and 13-8 Mo stainless steel plates were joined by gas tungsten constricted arc welding(gTCAW) process in similar and dissimilar metal combinations using 13-8 Mo stainless steel filler wire. The similar and dissimilar metal welds made in solutionized condition were subjected to standard post weld hardening treatments direct ageing at 485 ℃, soaking for 31/2 hours followed by air cooling(ageing treatment of maraging steel) and direct ageing at 510 ℃, soaking for 4 h followed by air cooling(ageing treatment of 13-8 Mo stainless steel). The joint characterization studies include microstructure examination, microhardness survey across the weldments and transverse weld tensile *** and dissimilar metal weldments responded to both the post weld ageing treatment. After post weld aging, increase in yield strength, UTS and slight reduction in % elongation of similar and dissimilar metal were observed. The observed tensile properties were correlated with microstructure and hardness distribution across the welds.

关键词： Maraging steel(250) 13-8 Mo stainless steel Mechanical properties Microstructure

AN M/M/C RETRIAL QUEUEINg SYSTEM WITH BERNOULLI vACATIONS

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Journal of Systems Science and Systems Engineering 2009年第2期18卷 222-242页

作者： B.krishna KUMAR R.RUKMANI v.THANgARAJ Department of Mathematics College of EngineeringAnna UniversityChennai600 025India Department of Mathematics Pachaiyappa's CollegeChennai600030India Ramanujan Institute for Advanced Study in Mathematics University of MadrasChennai600 005India

In this paper, a steady-state Markovian multi-server retrial queueing system with Bernoulli vacation scheduling service is studied. Using matrix-geometric approach, various interesting and important system performance measures are obtained. Further, the probability descriptors like ideal retrial and vain retrial are provided. Finally, extensive numerical illustrations are presented to indicate the quantifying nature of the approach to obtain solutions to this queueing system.

关键词： Retrial queue Bernoulli vacation matrix-geometric methods busy period vain retrial ideal retrial

Influence of Nano-Materials on Mechanical and Permeation Characteristics of High Strength Concrete

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Journal of Wuhan University of Technology(Materials Science) 2022年第3期37卷 416-422页

作者： K v S gopala krishna Sastry M Srinivasula Reddy A Ravitheja Civil Engineering G Pulla Reddy Engineering CollegeKurnoolAPIndia SvR Engineering College NandyalAndhra PradeshIndia

Efforts have been made to evaluate the influences of the addition of nanoparticles on the strength,durability and mineralogical changes of high strength concrete(HSC).Therefore,mixes were prepared for conventional concrete mix(CCM)of M80 ***,various mixes were prepared by replacing cementitious materials initially with 1%Nano-CaCO_(3)(NC),2%NC,3%NC in the CCM,and then 1%NC and Nano-SiO_(2)(NS)NS,2%NC and NS,3%NC and NS(NC and NS were in equal proportion)in the *** developed concretes were then evaluated for mechanical properties,permeation characteristics,and mineralogical *** the studies,it is found that the concrete at 2%NCS possesses superior mechanical and superior permeation characteristics of all the mixes.A clear variation in the mineralogical structure with the addition of nanoparticles has been observed.

关键词： high strength concrete nano silicon dioxide nano calcium carbonate mechanical properties permeation properties

Some hydrodynamic aspects of 3-phase inverse fluidized bed

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China Particuology 2007年第5期5卷 351-356页

作者： krishna S.v.S.R. Bandaru D.v.S. Murthy K. krishnaiah Department of Chemical Engineering Indian Institute of Technology Madras

Hydrodynamics of 3-phase inverse fluidized bed is studied experimentally using low density particles for different liquid and gas velocities. The hydrodynamic characteristics studied include pressure drop, minimum liquid and gas fluidization velocities and phase holdups. The minimum liquid fluidization velocity determined using the bed pressure gradient, decreases with increase in gas velocity. The axial profiles of phase holdups shows that the liquid holdup increases along the bed height, whereas the solid holdup decreases down the bed. However, the gas holdup is almost uniform in the bed.

关键词： Inverse fluidization Inverse fluidized bed Hydrodynamics Phase holdup Axial holdup