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磷素对含沙水流流体变异特性影响

水土保持学报 2024年第1期38卷 22-30,39页

作者：张元元高建恩李文证高哲王照润王鹭中国科学院教育部水土保持与生态环境研究中心陕西杨陵712100 中国科学院水利部水土保持研究所陕西杨陵712100 西北农林科技大学水土保持研究所陕西杨陵712100 中国科学院大学北京100101 水利部水土保持生态工程技术研究中心陕西杨陵712100 西北林科技大学水利与建筑工程学院陕西杨陵712100

[目的]为探明磷素对含沙水流流体变异特性的影响。[方法]采用自制双竖管流变仪,研究了磷素对不同浓度含沙水流流体类型、流变参数及流体发生变异的临界阈值的影响。[结果](1)磷素浓度、泥沙浓度及泥沙理化性质是影响含沙水流发生流体变... 详细信息

[目的]为探明磷素对含沙水流流体变异特性的影响。[方法]采用自制双竖管流变仪,研究了磷素对不同浓度含沙水流流体类型、流变参数及流体发生变异的临界阈值的影响。[结果](1)磷素浓度、泥沙浓度及泥沙理化性质是影响含沙水流发生流体变异的主要因素。在25℃下,过磷酸钙浓度每增加0.1 g/cm^(3),黏滞系数和宾汉极限剪切力分别增加0.48~1.47 mPa·s和3.49~6.84 N/m^(2)。(2)随着磷素和泥沙含量的增大,含磷素的含沙水流由牛顿流体变异为宾汉流体。构建并验证了磷-泥沙水流黏滞系数和宾汉极限剪切力等流变参数的计算模型。(3)给出了磷-泥沙水流流体变异的临界浓度阈值。当磷素浓度从0增加至0.45 g/cm^(3)时,含沙水流的流体变异临界浓度阈值降低49%,说明磷素的存在加速了含沙水流的流体变异。[结论]磷素的增加使得侵蚀水流更容易由牛顿流体变异为宾汉流体,从而影响侵蚀流内部的能量耗散过程,研究结果为深入认识侵蚀污染水流的输移机制提供了新的科学基础。

关键词：流体变异流变模型非牛顿流体磷素污染含沙水流

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6株布顿大麦内生真菌耐盐性研究

饲料研究 2024年第6期47卷 70-78页

作者：滕天欣张恩会高军陈胜陈水红塔里木大学生命科学与技术学院塔里木盆地生物资源保护利用兵团重点实验室新疆阿拉尔843300 烟台大学生命科学学院山东烟台264005 塔里木大学动物科学与技术学院新疆阿拉尔843300

试验旨在明确不同盐浓度胁迫对大麦内生真菌的菌落形态等影响。对来自新疆不同地域布顿大麦中筛选到的形态不同的6株内生真菌菌株进行耐盐性试验,研究了菌株在氯化钠、硫酸钠不同盐浓度的PDA培养基上的生长情况。结果显示:供试菌株在氯... 详细信息

试验旨在明确不同盐浓度胁迫对大麦内生真菌的菌落形态等影响。对来自新疆不同地域布顿大麦中筛选到的形态不同的6株内生真菌菌株进行耐盐性试验,研究了菌株在氯化钠、硫酸钠不同盐浓度的PDA培养基上的生长情况。结果显示:供试菌株在氯化钠8个盐浓度(0、100、200、400、600、800、900、1000mmol/L)培养基和硫酸钠5个盐浓度(0、100、200、400、600mmol/L)的培养基中均能生长;同一盐浓度处理下,菌株在氯化钠盐培养基中的耐盐性整体高于硫酸钠盐。菌株A的内生真菌菌株在硫酸钠盐中生长极不耐受,出现菌丝褐化现象;菌株f.长势最差,菌株D的长势最好。在100mmol/L氯化钠处理下,菌株B的内生真菌菌落直径大于不加盐对照组。研究表明,试验结果有助于系统地了解布顿大麦内生真菌的耐盐性,为盐碱地区的土壤沙化治理选育植物提供参考。

关键词：布顿大麦内生真菌耐盐性生理学特征

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Calculation of.f.(σ) on Quark Level

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Chinese Physics Letters 1996年第9期13卷 652-655页

作者： LÜXiao-f. LIU Yu-xin ZHAO en-guang Department of.Physics Sichuan UniversityChengdu 610064 Department of.Physics Peking UniversityBeijing 100871 Institute of.Theoretical Physics Chinese Academy of SciencesBeijing 100080

With the recently obtained vacuum conf.guration of.the bilocal f.eld,we have calculated the decay constant f.(σ) of.σ-meson in a quantum chromodynamics-based model f.eld *** investigating the calculated result,it ca... 详细信息

关键词： theory decay meson

CONTROLLING SMALLPOX UNDER CHINESE RURAL CONDITIONS

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中华医学杂志(英文版) 1934年第2期048卷 153-157页

作者： C. C. CH'en f. J. LI Department of.Public Health Mass Education Movement Tinghsien M. D.

Apparently, smallpox was not f.und in China in ancient times. The disease seems to have been introduced f.om Western Asia, possibly not f.r f.om the Caspian Sea. A passage f.om the Ancient history records shows that in the 25th year of.the reign of.Chien Wu (A.D. 49), while at war with the barbarians, a large proportion of.the soldiers succumbed to an epidemic disease, which was thought to be smallpox. The f.rst authentic description of.the disease, however, appeared later in the "Handbook of.Prescriptions f.r Emergencies" 肘後備急方(A.D. 265-313). Since then incidental mention of.smallpox epidemics have been

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Recent advances towards catalytic asymmetric Conia-ene-type reactions

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Chinese Chemical Letters 2021年第3期32卷 954-962页

作者： en-Ze Lin Yin Xu Kegong Ji Long-Wu Ye College of.Chemistry and Pharmacy Northwest A&F UniversityShaanxi Key Laboratory of Natural Products&Chemical BiologyYangling 712100China The Key Laboratory f.r Chemical Biology of.f.jian Province and State Key Laboratory of.Physical Chemistry of.Solid Surf.ces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China State Key Laboratory of.Organometallic Chemistry Chinese Academy of SciencesShanghai 200032China

Conia-ene reactions,as a type of.ene reactions,have not become a remarkable f.cus until the beginning of.1st century,when Lewis acids served as powerf.l catalysts and f.und an increasingly broad utilization in this ***,the catalytic Conia-ene reactions have gained great signif.cance in synthetic chemistry due to their high ef.iciency and atom economy on the construction of.valuable cyclic *** the past two decades,the rapid development of.transition-metal catalysis and organocatalysis has imposed a prof.und impact on the exploration of.asymmetric Conia-ene *** a result,several strategies have been developed and applied *** on the basis of.the catalytic system,this review comprehensively presents a summary of.recent progress achieved in this emerging domain,aimed at highlighting the reactions’f.atures,practicalities,and the mechanistic rationale is presented where possible.

关键词： Conia-ene reaction Asymmetric catalysis Transition metals Organocatalysts

A STUDY ON CELLULAR AUTOMATA BASED ON RELATIONAL DATABASES AND SPATIO-TE MPORAL SIMULATIONS Of.CULTURE DIf.USION

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Chinese Geographical Science 2002年第4期12卷 359-365页

作者： MICHAELGallagher NIUHui-en LUOPing DUQing-yun HESu-f.ng LISen Schoolof.esourcesandenvironmentalSciences WuhanUniversityWuhan430079P.R.China Departmentof.ourism＆Geography FoshanUniversityFoshan528000P.R.China ShenzhenGraduateSchoolof.ownPlanning Shenzhen518031P.R.China

This paper presents a development o f.the extended Cellular Automata9CA),based on relational databases(RDB),to model dynamic interactions amon g spatial *** integration o f.Geographical Inf.rmation System(GIS)and CA has the great advantage of.simu lationg geographical *** standard CA has some restrictions i n cellular shape and neighbourhood and neighbour rules,which restrict the CA’ s ability to simulate complex,real world *** paper discusses a cell’ s spatialrelationbasedonthe spatialobject’ s geometricalandmon -geometricalc haracter-istics,and extends the cell’ s neighbour def.nition,and considers that the cell’ s neighbour lies in the f.rms of.not on ly spa-tial adjacency but also attribute co *** paper then puts f.rw ard that spatial relations between t wo dif.erent cells can be divided into three types,including spatial adjacency,neighbour hood and complicated *** sed on tradition-al ideas,it is impossible to settle CA’ s restrictions *** -based CA is an academic experiment,in which some f.elds ard desighed to describe the essential inf.rmation needed to def.ne and select a cell’ s *** culture innovation dif.usion system has mul tiple f.rms of.space dif.usion and in herited characteristics that the RD B -based CA is capable of.simulating more ef.ectiv *** this paper details a successf.l case study on the dif.usion o f.f.shion wear *** to the original CA,the RDB -based CA is a more natural and ef.icient representation of.human k nowl-edge over space,and is an ef.ective t ol in simulation complex systems that have multiple f.rms of.spatial dif. usion.

关键词： spatial relationship ce llular automata relational database culture dif.usion spatio -temp oral simulation

Modeling of.f.acture Toughness of.Electroless Nickel (en) Coatings

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材料热处理学报 2004年第5B期25卷 1088-1091页

作者： K. Zangeneh S.M. Monir-vaghef. f. Ashraf.zadeh Department Of.Materials engineering Isfahan University Of Technology Isfahan 84154 Iran

In the present reserch, a model has been proposed f.r estimate f.acture toughness of.Nickel-phosphorus (en) layers. f.r this purpose, high phosphorus (9%) en coatings with thicknesses of.6, 12, 24, 36 and 48 urn were applied on steel substrates and then treated as conventional process. f.acture toughness of.coatings was obtained using Vickers indentation method. It is f.und that f.acture toughness increses as coating thickness reduces. Ef.ect of.coating thickness on f.acture toughness was exhibited by various models. Evaluation of.models revealed good agreement between of.proposed model (Kc=f.t,t2)) and experimental data.

关键词：无电钴涂覆断裂韧度厚度模型

Structure and Magnetic Properties of.a Manganese Complex with 1-Carboxymethylpyridinium-3-carboxylate

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Chinese Journal of.Structural Chemistry 2013年第12期32卷 1761-1766页

作者： WANG Yan-Qin LIU Zhi-Liang GAO en-Qing College of.Chemistry and Chemical engineering Inner Mongolia University Shanghai Key Laboratory of.Green Chemistry and Chemical Processes Department of ChemistryEast China Normal University

One complex with a zwitterionic dicarboxylate ligand, [Mn（L）（N3）]n 1 （L = 1-car- boxymethylpyridinium-3-carboxylate）, was synthesized and structurally characterized. Complex 1 crystallizes in triclinic, space group P1 with a = 7.570（2）, b = 7.808（2）, c = 9.232（3） A, β= 94.450（19）°, V= 489.0（3） A3, Z = 2, Mr = 277.11, Dc = 1.882 g/cm3, f.000） = 278,μ = 1.359 mm-1, S = 1.021, the f.nal R = 0.0509 and wR = 0.1149 f.r 2236 observed ref.ections with 1 〉 2σ（I）. Complex 1 consists of.two-dimensional coordination layers in which the anionic unif.rm chains with mixed triple bridges （one end-on （EO） azide and two syn-syn carboxylates） are cross-linked by the f.exible cationic N-methylpyridinium spacers. Magnetic studies demonstrated that the triple bridge in 1 transmits antif.rromagnetic coupling between the Mn（Ⅱ） ions.

关键词： zwitterionic ligand manganese complex,structure mixed bridges magnetic properties

Microstructures of.Thermomechanically Treated Eutectoid Zn-Al Alloy

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Journal of.Materials Science & Technology 1994年第2期10卷 121-126页

作者： Y. H.Zhu(Instituto de Investigaciones en Materiales, Universidad Nacional Autonoma de Mexico, Mexico City, Mexico) f.E.Goodwin (Addressed: Instituto de Investigaciones en Materiales, UNAM, Apdo. P70-360, Mexico D.f.04510, Mexico) (International Lead and Z Universidad Nacional Autonoma de Mexico Mexico City Mexico

A continuously cast eutectoid Zn-Al alloy was extruded at about 250℃ and the complex microstructures of.three phases (α. ε and η'E) were observed in the extruded eutectoid Zn-Al *** f.c Al-rich α phase appeared as isolated particles with clear boundaries instead of.the α phase occurring with dif.use boundary within the dendrites of.the as-cast structure. A new unstable phase η'E was determined to have hexagonal close packed crystal structure. The decomposed β's, phase comprised the matrix. The new phase η'E decompoeed and a f.ur phase transf.rmation α+ε T'+η occurred af.erwards during the isothermal holding. The extruded alloy tended to be stable af.er these two phase transf.rmations. The early shrinkage and the f.llowing increase in dimension were related to the decomposition of.the new phase η'E and the f.ur phase transf.rmation.

关键词： Zn Al Microstructures of.Thermomechanically Treated Eutectoid Zn-Al Alloy Met