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Annual Time-series Analy.es of Total Gaseous Mercury.Measurement and its Impact Factors on the Gongga Mountains in the Southeastern Fringe of the Qinghai-Tibetan Plateau

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Journal of Mountain Science 2008年第1期5卷 17-31页

作者： ZHU Wanze FU Xuewu FEng Xinbin Julia y. Lu Institute of Mountain Hazard and Environment Chinese Academy of Sciences Chengdu 610041 China State Key.Laboratory.of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China Department of Chemistry.and Biology Ryerson University Toronto Ontario M5B 2K3 Canada

Long-term monitoring programs for measurement of atmospheric mercury.concentrations are presently.recognized as powerful tools for local,regional and global studies of atmospheric long-range transport processes,and they.could also provide valuable information about the impact of emission controls on the global budget of atmospheric mercury.their observance and an insight into the global mercury.cy.le. China is believed to be an increasing atmospheric mercury.emission source. However,only.a few measurements of mercury.to our knowledge,have been done in ambient air over China. The highly.time resolved atmospheric mercury.concen-trations have been measured at Moxi Base Station (102°72′E 29°92′N,1640 m asl) of the Gongga Alpine Ecosy.tem Observation and Experiment Station of Chinese Academy.of Sciences (CAS) from May.2005 to June 2006 by.using a set of Automatic Atmospheric Mercury.Speciation Analy.ers (Tekran 2537A). Measurements were carried out with a time resolution of every.15 minutes. The overall average total gaseous mercury.(TGM) covering the measurement periods was 4±1.38 ng·m-3 (N=57310),which is higher than the global background level of approximately.1.5～2.0 ng·m-3. The measurements in all seasons showed a similar diurnal change pattern with a high concentration during day.ime relative to nighttime and maximum concentration near solar noon and minimum concentration immediately.before sunrise. The presence of diurnal TGM peaks during spring and summer was found earlier than that during autumn and winter. When divided seasonally.it was found that the concentrations of TGM were highest in winter with 6.13 ± 1.78 ng·m-3 and lowest in summer with 3.17 ± 0.67 ng·m-3. There were no significant differences in TGM among wind sectors during each season. Whereas Hg generally.exhibited significant correlations with the parameters,such as temperature,saturated vapor pressure,precipitation,ultraviolet radiation (UV) and atmospheric pressure at the whole measurement stage,

关键词： Total gaseous mercury.(TGM) diurnal variability seasonal variability meteorological factor Gongga Mountains

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微生物自修复混凝土的制备及性能研究

价值工程 2024年第10期43卷 74-76页

作者：李茜茜刘昭洋赵明敏 Serina ng 王进春石家庄市长安育才建材有限公司石家庄051430 石家庄市建筑功能材料产业技术研究院石家庄051430 四川砼道科技有限公司成都610200

通过嗜碱芽孢杆菌胶与匹配的胶结液制备微生物修复剂,并自主研发疏水剂,通过向混凝土中加入疏水剂,改变了混凝土颗粒结构、降低土微粒界面活性,使之可以更好地配合微生物胶结对混凝土的固化,固化后的混凝土韧性大大提升,避免混凝土发生... 详细信息

通过嗜碱芽孢杆菌胶与匹配的胶结液制备微生物修复剂,并自主研发疏水剂,通过向混凝土中加入疏水剂,改变了混凝土颗粒结构、降低土微粒界面活性,使之可以更好地配合微生物胶结对混凝土的固化,固化后的混凝土韧性大大提升,避免混凝土发生破坏后强度瞬间丧失的情况发生。并通过大蒜素水溶液,在后期加强微生物对混凝土的加工作用,实现混凝土的“自愈合”效果。

关键词：微生物自修复疏水剂混凝土裂缝

A screen for bacterial endosy.bionts in the model organisms Tribolium castaneum, T. confusum, Callosobruchus maculatus, and related species

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Insect Science 2015年第2期22卷 165-177页

作者： Sara L. Goodacre Claudia Fricke Oliver y. Martin School of Biology University of Nottingham Queen's Medical Centre Nottingham NG7 2UH United Kingdom Institute for Evolution and Biodiversity University of Muenster Muenster D-48 149 Germany ETH ZOrich Experimental Ecology Institute for IntegrativeBiology D-USYS CH-8092 ZOrich Switzerland

Reproductive parasites such as Wolbachia are extremely.widespread amongst the arthropods and can have a large influence over the reproduction and fitness of their hosts. Undetected infections could thus confound the results of a wide range of studies that focus on aspects of host behavior, reproduction, fitness, and degrees of reproductive isolation. This potential problem has already.been underlined by.work investigating the in- cidence of Wolbachia infections in stocks of the model sy.tem Drosophila melanogaster. Here we survey.a range of lab stocks of further commonly.used model arthropods, fo- cusing especially.on the flour beetles Tribolium castaneum and Tribolium confusum, the cowpea weevil Callosobruchus maculatus and related species （Coleoptera： Tenebrionidae and Bruchidae）. These species are widespread stored product pests so knowledge of infec- tions with sy.bionts further has potential use in informing biocontrol measures. Beetles were assessed for infection with 3 known microbial reproductive parasites： Wolbachia, Rickettsia, Spiroplasma. Infections with some of these microbes were found in some of the lab stocks studied, although overall infections were relatively.rare. The consequences of finding infections in these or other species and the ty.e of previous studies likely.to be affected most are discussed.

关键词： Coleoptera reproductive isolation reproductive parasite sexual conflict sexual selection Wolbachia

Suppression of grain boundary.migration at cry.genic temperature in an extremely.fine nanograined Ni-Mo alloy

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Journal of Materials Science & Technology 2020年第22期54卷 65-69页

作者： J.Hu J.X.Li y.-N.Shi Sheny.ng National Laboratory.for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Institute of Advanced Materials East China JiaoTong UniversityNanchang 330013China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China

Microindentation creep tests on an electrodeposited extremely.fine(4.9 nm) nanograined(ng) Ni-14.2 at.% Mo(Ni-14.2 Mo) at both room temperature(RT) and liquid nitrogen temperature(LNT) demonstrated that lowering temperature retarded softening in the ng Ni-Mo alloy. The obtained strain rate sensitivity.at LNT was one order of magnitude lower than that at RT. Microstructural characterization revealed that mechanically.driven grain boundary.GB) migration was greatly.suppressed by.lowering temperature,which might be ascribed to the presence of solute Mo atoms that significantly.retarded coupled GB motion at LNT. Deformation was instead carried by.shear bands.

关键词： Extremely.fine nanograined metals Mechanically.driven grain boundary.migration Cry.genic temperature Shear bands Solute atoms

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丙烯墨水中颗粒相分散性问题研究

中国制笔 2024年第3期 30-36页

作者：潘勤敏张胜红林韶晖钱宵亮 ng Flor a T.T. 金桂英苏州大学江苏苏州215123 苏州雄鹰笔墨新材料有限公司江苏苏州215200 滑铁卢大学加拿大安大略省滑铁卢N2L 3G1

针对丙烯墨水中普遍存在的颗粒相分散问题,在对颗粒沉降原理进行简要介绍的基础上,就丙烯酸树脂的选择和改性,颗粒相的处理技术,分散剂、稳定剂、增稠剂等的研究进行了综述。

关键词：丙烯酸树脂墨水钛白粉沉降

熔融态铁氧化物碳氢还原热力学与动力学研究现状

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钢铁研究学报 2024年第2期36卷 150-162页

作者：卢立金王锋王海风邱健平晓东钢铁研究总院有限公司先进钢铁流程及材料国家重点实验室北京100081 钢研晟华科技股份有限公司北京100081

氢能在冶金领域的应用是实现低碳发展的重要途经之一。目前虽然在富氢高炉和氢基直接还原炼铁领域取得诸多成果,但在碳氢熔融还原炼铁仍有许多不足之处。通过分析碳、CO以及氢气还原熔融态铁氧化物的研究,总结熔融还原过程基本热力学特... 详细信息

氢能在冶金领域的应用是实现低碳发展的重要途经之一。目前虽然在富氢高炉和氢基直接还原炼铁领域取得诸多成果,但在碳氢熔融还原炼铁仍有许多不足之处。通过分析碳、CO以及氢气还原熔融态铁氧化物的研究,总结熔融还原过程基本热力学特点,并对影响动力学参数的因素进行分析。结果表明,在熔融温度(1369℃)以上氢气还原FeO在热力学上有一定的优势。还原温度高于1538℃,(即还原物和还原产物都为熔融态),还原气体流量为3 mL/min以及碱度为1.1~1.3时有利于熔融反应的进行。关于碳氢还原熔融态铁氧化物的研究还不充分,还需要进一步解析还原过程、限制环节以及微观机制等。

关键词：熔融还原氢冶金热力学动力学

NUMERICAL STUDIES OF A CLASS OF COMPOSITE PRECONDITIONERS

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Journal of Computational Mathematics 2014年第2期32卷 136-151页

作者： Qiang Niu Michael ng Mathematics and Phy.ics Centre Xi'an Jiaotong-Liverpool University Suzhou 215123 China Department of Mathematics Hong Kong Baptist University Kowloon Tong Hong Kong

In this paper, we study.a composite preconditioner that combines the modified tangential frequency.filtering decomposition with the ILU（O） factorization. Spectral property.of the composite preconditioner is examined by.the approach of Fourier analy.is. We illustrate that condition number of the preconditioned matrix by.the composite preconditioner is asy.ptotically.bounded by.O（hp -2/3） on a standard model problem. Performance of the composite preconditioner is compared with other preconditioners on several problems arising from the discretization of PDEs with discontinuous coefficients. Numerical results show that performance of the proposed composite preconditioner is superior to other relative preconditioners.

关键词： Preconditioner ILU Tangential frequency.filtering decomposition GMRES.

Lowered testosterone in male obesity. mechanisms, morbidity.and management

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Asian Journal of Andrology 2014年第2期16卷 223-231,I0008页

作者： Mark ng Tang Fui Department of Medicine Austin Health University of Melbourne Melbourne Department of Endocrinology Austin Health Melbourne Victoria Australia

With increasing modernization and urbanization of Asia, much of the future focus of the obesity.epidemic will be in the Asian region. Low testosterone levels are frequently.encountered in obese men who do not otherwise have a recognizable hy.othalamic-pituitary.testicular （HPT） axis pathology. Moderate obesity.predominantly.decreases total testosterone due to insulin resistance-associated reductions in sex hormone binding globulin. More severe obesity.is additionally.associated with reductions in free testosterone levels due to suppression of the HPT axis. Low testosterone by.itself leads to increasing adiposity. creating a self-perpetuating cy.le of metabolic complications. Obesity.associated hy.otestosteronemia is a functional, non-permanent state, which can be reversible, but this requires substantial weight loss. While testosterone treatment can lead to moderate reductions in fat mass, obesity.by.itself, in the absence of sy.ptomatic androgen deficiency. is not an established indication for testosterone therapy. Testosterone therapy.may.lead to a worsening of untreated sleep apnea and compromise fertility. Whether testosterone therapy.augments diet- and exercise-induced weight loss requires evaluation in adequately.designed randomized controlled clinical trials.

关键词： androgens hy.ogonadism obesity testosterone weight loss

On compact splitting complex submanifolds of quotients of bounded sy.metric domains

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Science China Mathematics 2017年第6期60卷 1057-1076页

作者： MOK ngaiming ng SuiChung Department of Mathematics The University of Hong Kong Department of Mathematics Shanghai Key Laboratory of PMMPEast China Normal University

We study.compact complex submanifolds S of quotient manifolds X =Ω/F of irreducible bounded sy.metric domains by.torsion free discrete lattices of automorphisms, and we are interested in the characterization of the totally.geodesic submanifolds among compact splitting complex submanifolds S C X, i.e., under the assumption that the tangent sequence over S splits holomorphically. We prove results of two ty.es. The first ty.e of results concerns S C X which are characteristic complex submanifolds, i.e., embedding Ω as an open subset of its compact dual manifold M by.means of the Borel embedding, the non-zero （1, 0）-vectors tangent to S lift under a local inverse of the universal covering map π → X to minimal rational tangents of M. We prove that a compact characteristic complex submanifold S C X is necessarily.totally.geodesic whenever S is a splitting complex submanifold. Our proof generalizes the case of the characterization of totally.geodesic complex submanifolds of quotients of the complex unit ball B^n obtained by.Mok （2005）. The proof given here is however new and it is based on a monotonic property.of curvatures of Hermitian holomorphic vector subbundles of Hermitian holomorphic vector bundles and on exploiting the splitting of the tangent sequence to identify.the holomorphic tangent bundle Ts as a quotient bundle rather than as a subbundle of the restriction of the holomorphic tangent bundle Tx to S. The second ty.e of results concerns characterization of total geodesic submanifolds among compact splitting complex submanifolds S C X deduced from the results of Aubin （1978） and y.u （1978） which imply.the existence of Kahler-Einstein metrics on S C X. We prove that compact s- plitting complex submanifolds S C X of sufticiently.large dimension （depending on ） are necessarily.totally.geodesic. The proof relies on the Hermitian-Einstein property.of holomorphic vector bundles associated to TS, which implies that endomorphisms of such bundles are parallel, and the co

关键词： bounded sy.metric domains tangent sequence splitting complex submanifolds varieties of minimal rational tangents K/ihler-Einstein metrics