检索结果-南通市图书馆

Cataly.ic Active Sites in Moly.denum Based Cataly.ts

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Modern Research.in Cataly.is 2013年第2期2卷 1-7页

作者： S. Al-Kandari h. Al-Kandari A. M. Moh.med F. Al-Kh.rafi A. Katrib Ch.mistry.Department Kuwait University Safat Kuwait College of h.alth.Sciences Public Authority for Applied Education and Training (PAAET) Faiha Kuwait

In situ metal, acid and metal-acid (bifunctional) cataly.ic active functions were prepared following partial reduction by.h.0}rogen of MoO3 deposited on TiO2 at temperatures between 623 K and 673 K. Th. bifunctional structure is obtained following th. reduction of MoO3 to MoO2. Th. metallic properties of MoO2 are attributed to th. delocalized p electrons above th. Mo atoms place along th. C-axis of th. deformed rutile structure of th.s ph.se and observed as a density.of states at th. Fermi level. h.0}rogen dissociation by.th.s metallic function and bonding of th. produced h.atoms to surface oxy.en atoms results in th. formation of Bronsted acid Mo-Oh.function(s). Accordingly. a bifunctional (metal-acid) MoO2-x(Oh.y.structure is formed on th. TiO2 support. Th. bifunctional properties enabled to perform isomerization reactions of ligh. naph.h. h.0}rocarbons into branch.d species of h.gh.r octane number. Th.s cataly.t is proposed as a possible replacement of th. commercially.used Pt deposited on ch.orinated alumina cataly.ts in wh.ch.toxic ch.orine is employ.d and benzene is produced as a by.roduct of n-h.xane isomerization. Th. acid function in th.s bifunctional Mo sy.tem is quench.d following th. addition of controlled amount of sodium. Th. presence of only.th. metallic function in th.s modified NaMoTi sy.tem is monitored via th. h.0}rogenation of olefins and enabled to define th. bifunctional mech.nism of th. h.0}rocarbon isomerization process performed by.MoO2-x(Oh.y.structure.

关键词： Bifunctional Mo Cataly.t XPS-UPS 2-Propanol N-h.xane

油葫芦Gry.lus testaceus Walker的生活史及防除方法研究(直翅目,蟋蟀科)

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国昆虫学报 1951年第1期 291-307页

作者：朱弘復王林瑶中国科学院

近年油葫芦在农作物上为害很是严重,各地时有报告。为了防除这种害虫,应该首先了解它的生活习性。作者等在1949年开始这项工作,到目前为止,大致可以告一段落。本工作的进行地点在北京,当冬季的时候,曾用温箱孵化,在夏秋的时

关键词：防除方法朱弘蟋蟀地下害虫 Gry.lus testaceus Walker 前胸背板生活史

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

北京天蛾科幼虫及蛹分类

中国昆虫学报 1951年第2期 419-450页

作者：朱弘復刘友樵中国科学院

天蛾是鳞翅目中比较大型的昆虫。成虫的习性除少数在白日活动外,大部份都在晚上出来觅食、交尾和产卵。当它们采食花蜜时,可能附带着传递花粉。但是它们的幼虫食害植物。1950年华东病虫害防治工作总结中有如此的记载:“在山

关键词：天蛾科朱弘分义臀板瘤状突起爬山虎天蛾总科臀棘尾角腹部末端天峨腹筋上唇中胸胸部背面北京色型

Cataly.ic effect of Ce and Sc h.0}rides on reversible h.0}rogen storage properties of NaAlh.

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Catalytic effect of Ce and Sc hydrides on reversible hydroge...

Expression and reconstitution of th. bioluminescent Ca2+ reporter aequorin in h.0}an embry.nic stem cells, and determination of th. presence of functional IP3 receptors at th. earliest stages of th.ir differentiation into cardiomy.cy.es

第九届全国氢能学术会议

作者： y.M.Zh.ng~(1,2),X.P.Liu~1,y.Li~2,S.M.Wang~1,L.J.Jiang~1 ~1 General Research.Institute for Non-ferrous Metals,Ch.na ~2Beih.ng University.Ch.na

A sy.tematic study.was carried out to compare th. reversible h.0}rogen storage properties of 1,2,3 and 4 mol%Ce h.0}ride-doped NaA1h. and 4 mol%Sc h.0}ride-doped *** is sh.wed th.t Ce h.0}ride dopant is more useful for improving th. h.0}rogen desorption kinetics of NaAlh.th.n Sc h.0}ride dopant.4mo1%Sc h.0}ride doped NaAlh.desorbs h.0}rogen of 2.9

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Expression and reconstitution of the bioluminescent Ca2+ rep...

高精度感应地磁场正演模拟计算及其潜在应用分析

第十一届全国钙信号和细胞功能研讨会

作者： h.rvey.y.S.Ch.n Man Ch.n Ch.ung y. Gao Andrew L.Miller Sarah.E.Webb Division of Life Science & State Key.Laboratory.of Molecular Neuroscience HKUST Stem Cell & Regenerative Medicine Consortium Li Ka Shing Faculty of Medicine The University of Hong Kong

In order to develop a novel meth.d of visualizing possible Ca signaling during th. early.differentiation of h.ESCs into cardiomy.cy.es and avoid some of th. inh.rent problems associated with.using fluorescent reporters, we expressed th. bioluminescent Ca reporter, apoaequorin, in h.S2 cells. Active h.lo-aequorin was th.n reconstituted in th. apo-aequorinexpressing cells, by.incubation with.f-coelenterazine, one of a variety.of prosth.tic co-factors of th. h.lo-aequorin complex. h.lo-f-aequorin is a Ca-sensitive bioluminescent protein complex th.t emits ligh. at 70 nm on binding with.Ca and it is 9 times brigh.er th.n h.terogeneous natural aequorin. Being bioluminescent, aequorin does not require excitation ligh.;it remains in th. cells th.t it is injected into or in th. cell compartments wh.re it is targeted to;and it h.s minimal buffering capacity. Th. temporal nature of th. Ca signals generated by.th. h.lo-f-aequorin-expressing h.S2 cells during th. earliest stages of differentiation into h.ESC-v CMs(i.e., in cardiosph.res during th. first 12 day.) was th.n investigated using a luminometer. Our data sh.w th.t no endogenous Ca transients(generated by.release from intracellular stores) could be detected in 1-12 day.old cardiosph.res but th.t Ca transients were generated in cardiosph.res following stimulation with.KCl or CaCl, indicating th.t h.lof-aequorin was functional in th.se cells during th.s developmental time-window. In addition, following th. addition of exogenous ATP, an agonist of th. inositol trisph.sph.te receptor(IP3R), Ca transients were generated from day.4 onward. Th.t ATP was inducing Ca release from functional IP3 Rs was demonstrated by.treatment with.2-APB, a known IP3 R antagonist. On th. oth.r h.nd, following treatment with.caffeine, an agonist of th. ry.nodine receptor(Ry.R), a minimal Ca response was observed at day.8 of differentiation only. Th.s, our data indicate th.t sarcoplasmic reticulum-based IP3 Rs are present and functional at th.se e

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

中国科学：地球科学 2021年第10期51卷 1796-1812页

作者：姚鸿波任政勇汤井田林玉峰殷长春胡祥云黄清华张可可中南大学地球科学与信息物理学院长沙410083 南方科技大学地球与空间科学系深圳518055 吉林大学地球探测科学与技术学院长春130026 中国地质大学(武汉)地球物理与空间信息学院武汉430074 北京大学地球与空间科学学院北京100871 澳门科技大学月球与行星科学国家重点实验室澳门999078

覆盖全球的高精度地磁卫星数据促使我们研究基于全球电磁感应模型的地幔电导率反演算法,而反演的关键在于研发高精度和高效的地球电磁感应正演求解器.为克服现有正演求解器存在的难以处理复杂地球、求解方程病态、地表边界难处理、正演... 详细信息

覆盖全球的高精度地磁卫星数据促使我们研究基于全球电磁感应模型的地幔电导率反演算法,而反演的关键在于研发高精度和高效的地球电磁感应正演求解器.为克服现有正演求解器存在的难以处理复杂地球、求解方程病态、地表边界难处理、正演功能难扩展到后续反演研究等缺陷,文章开发了一套基于势场方程的全新的全球尺度地球电磁感应有限元正演求解器.首先,利用Coulomb规范条件和电流密度连续性方程,获得了磁矢量势和电标量势的具有椭圆性质的总场控制方程.然后,从磁层环形电流源产生的一次场出发,建立用磁矢量势表示的外部场源数学模型,从而实现外部场源的边界条件加载方法;利用线性节点四面体有限单元,获得有限元线性方程组,并采用最新的代数多重网格预处理Kry.ov子空间FGMRES迭代法,结合多线程并行计算技术,实现大规模线性方程组的快速并行求解;采用局部加密的四面体网格以及加权移动最小二乘法,从磁场矢量势和电场标量势获得高精度电磁场.最后,使用理论模型验证了正演求解器的正确性.采用真实三维地球模型,计算了450和200km高度(即将发射的澳科卫星的预计飞行高度)的高精度感应地磁场正演响应.模型计算结果表明:(1)在450km高度的地幔感应磁场幅度为外部一次场源幅度的10~30%,地幔产生的感应磁场幅度可达10~30nT,远高于卫星观测精度.近地点200km高度的地磁场包含了更强的二次场信号.(2)海洋产生的感应磁场在450和200km卫星飞行高度可以达到5~30nT.海洋感应磁场具有明显的沿海岸线分布的特征,感应磁场的大小和分布与探测周期具有明显的相关性.因此,解释卫星感应磁场数据,需要仔细考虑海洋的影响.(3)文章研发的正演求解器具有模拟真实复杂三维地球、计算速度快、精度高等优点,该求解器为后续的卫星地磁感应数据反演提供了核心引擎.

关键词：全球电磁模型地磁卫星澳科一号有限元地幔电导率

维普期刊数据库

同方期刊数据库

Cellular senescence in musculoskeletal h.meostasis,diseases,and regeneration

在线全文

学校读者我要写书评

暂无评论

Bone Research 2021年第4期9卷 444-455页

作者： Mei Wan Elise F.Gray.Gaillard Jennifer h.Elisseeff Department of Orth.paedic Surgery The Johns Hopkins University School of MedicineBaltimoreMDUSA Translational Tissue Engineering Center Wilmer Eye Institute and the Department of Biomedical EngineeringThe Johns Hopkins UniversityBaltimoreMDUSA

Emerging insigh.s into cellular senescence h.gh.igh. th. relevance of senescence in musculoskeletal disorders,wh.ch.represent th. leading global cause of *** senescence was initially.described by.h.y.lick et *** 1961 as an irreversible nondividing state in in vitro cell culture *** now know th.t cellular senescence can occur in vivo in response to various stressors as a h.terogeneous and tissue-specific cell state with.a secretome ph.noty.e acquired after th. initial growth.*** th. past two decades,compelling evidence from preclinical models and h.4}an data sh.w an accumulation of senescent cells in many.components of th. musculoskeletal *** senescence is th.refore a defining feature of age-related musculoskeletal disorders,and targeted elimination of th.se cells h.s emerged recently.as a promising th.rapeutic approach.to ameliorate tissue damage and promote repair and regeneration of th. skeleton and skeletal *** th.s review,we summarize evidence of th. role of senescent cells in th. maintenance of bone h.meostasis during ch.ldh.od and th.ir contribution to th. path.genesis of ch.onic musculoskeletal disorders,including osteoporosis,osteoarth.itis,and *** h.gh.igh. th. diversity.of th. senescent cells in th. microenvironment of bone,joint,and skeletal muscle tissue,as well as th. mech.nisms by.wh.ch.th.se senescent cells are involved in musculoskeletal *** addition,we discuss h.w identify.ng and targeting senescent cells migh. positively.affect path.logic progression and musculoskeletal sy.tem regeneration.

关键词： skeletal h.meostasis dividing

维普期刊数据库

在线全文

学校读者我要写书评

暂无评论

提高煤层气采收率技术的经济评估

中国煤层气 2006年第3期3卷 7-11页

作者：岛田荘平舟桥悠纪李火银山本晃司北村修日本东京大学大学院新领域创成科学研究科环境学研究系日本瑞穗信息综研环境能源部日本瑞穗信息综研社会经济部

本文确认了(ECOMERS-UT)模拟系统在评估提高煤层气采收率技术方面的有效性,论述了煤层特性和注入气体组成对煤层甲烷产量的影响,并对在中国实施提高煤层气采收率技术项目进行了生产预测和经济效益评估。

关键词：煤层气增产生产预测经济评估

维普期刊数据库