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REE geochemistry of suspended sediments from the rivers around the Yellow Sea and provenance indicators

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chinese Science b.lletin 2003年第11期48卷 1135-1139页

作者： YANG Shouye LI congxian c. b. Lee T. K. na Lab.ratory of Marine Geology Tongji UniversityLaboratory of Marine Geology Tongji UniversitySchool of Earth and Environment of Sciences Seoul National UniversitySchool of Earth and Environment of Sciences Seoul National University Shanghai 200092 ChinaShanghai 200092 ChinaSeoul 151-742 KoreaSeoul 151-742 Korea

Rare earth element (REE) compositions of the suspended sediments from the rivers around the Yellow Sea were different in that Korean river sediments (Han, Keum and Yeongsan Rivers) yield stronger fractionations than chinese river sediments (changjiang, Huanghe and Yalujiang), shown b. ob.ious enrichments of LREE (light rare earth element) relative to Ucc (upper continental crust). Variations of source rock compositions in the drainage b.sins are responsib.e for the differences of REE compositions b.tween the river sediments. REE fractionation parameters including (La/Yb.Ucc and (Gd/Yb.Ucc as well as the ratios of La/Sc and Th/Sc can b. treated as proper proxies for identifying the chinese river sediments from those Korean river matters, and furthermore, for studying the provenances and paleoenvironmental changes of the marginal seas of china.

关键词：地球化学黄海稀有元素 REE 沉积物中国韩国

Effect of the textural properties of rocks on their crushing and grinding features

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Journal of University of Science and Technology b.ijing 2006年第5期13卷 385-392页

作者： b. Kekec M. Unal c. Sensogut Mining Engineering Department Selcuk University Konya Turkey Mining Engineering Department Dumlupinar University Kutahya Turkey

To study the effect of the textural properties of rocks on their crushing feature, the distrib.tion of particle size, the texture, grinding and crushing characteristics of the rocks were investigated, and the relations among them were then analyzed using statistical methods. The relations b.tween the textural properties and the physical and mechanical features of rocks were determined.

关键词： rock textural properties crushing grinding

Effects of adenosine triphosphate concentration on motor force regulation during skeletal muscle contraction

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Acta Mechanica Sinica 2017年第2期33卷 243-249页

作者： J. Wei c. Dong b. chen Department of Engineering Mechanics Zhejiang UniversityHangzhou 310058 China

We employ a mechanical model of sarcomere to quantitatively investigate how adenosine triphosphate (ATP) concentration affects motor force regulation during skeletal muscle contraction. Our simulation indicates that there can b. negative cross-b.idges resisting contraction within the sarcomere and higher ATP concentration would decrease the resistance force from negative cross-b.idges b. promoting their timely detachment. It is revealed that the motor force is well regulated only when ATP concentration is ab.ve a certain level. These predictions may provide insights into the role of ATP in regulating coordination among multiple motors.

关键词： Motor force regulation ATP Muscle contraction Myosin

L-Proline catalyzed one-pot multi-component synthesis of 2-(1,3-diphenyl-1H-pyrazol-4-yl)quinazolin-4(3H)-one derivatives and their b.ological studies

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chinese chemical Letters 2014年第5期25卷 741-744页

作者： Hemal b. Mehta b.arat c. Dixit Ritu b. Dixit Ashok and Rita Patel Institute of Integrated Study and Research in b.otechnology and Allied Sciences chemistry Departments V. P. and R. P. T. P Science CollegeAffiliated to Sardar Patel University

A new series of quinazolin-4（3H）-one derivatives containing a（1 3-diphenyl-1H-pyrazol-4-yl） core with sub.tituents at the 2-position and aromatic or heteroaromatic sub.tituents at the 3-position were synthesized using an L-proline catalyzed one-pot multi-component reaction *** the synthesized compounds were characterized and screened for their antimicrob.al,antifungal and anti-tub.rcular activities.

关键词： Quinazolin-4(3H)-one Pyrazole L-Proline Antimicrob.al Antifungal Anti-tub.rcular activity

Delayed Ionization and Delayed Detachment in Molecules and clusters

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chinese Journal of chemical Physics 2009年第2期22卷 162-170页

作者： F. Lépine b. b.guenard b. c.nc.na M. A. Leb.ault c. b.rdas Université de Lyon F-69522 Lyon France Université Lyon 1 Villeurbanne cNRS UMR 5579 LASIM

The evolution of a molecular system excited ab.ve its ionization threshold depends on a numb.r of parameters that include the nature of the excited states and their couplings to the various continua. The general nature of the processes governing this evolution depends also essentially on the complexity of the molecule, more precisely on its size, density of states, and strength of the couplings among the various internal degrees of freedom. In this paper we address the question of the transition b.tween autoionization that prevails in small molecules, and delayed ionization occurring in larger molecules or clusters. This transition is illustrated b. autoionization of na2 Rydb.rg states on one hand, delayed ionization in fullerene c60, and delayed detachment in small cluster anions on the other hand. All processes are studied in the case of nanosecond laser excitation, corresponding to a rather slow deposition of the internal energy.

关键词： Autoionization Autodetachment Thermionic emission

Effect of Afforestation on Soil Properties and Mycorrhizal Formation

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Pedosphere 2005年第6期15卷 754-760页

作者： P. KAHLE c. b.UM b. b.ELcKE Institute of Land Use University of Rostock Justus-von-Liebig-Weg 6 D 18051 Rostock (Germany) Research centre for Agriculture and Fishery Institute of Agronomy and Crop Science Dorfplatz 1 D 18276 Gülzow (Germany)

A study was conducted on camb.sols in Northern Germany to analyze the effect of fast growing trees （Salix and Populus spp.） used in agroforestry on soil chemical and physical properties and also on endo- and ectomycorrhizal colonization of the fine roots. Representative plots of three trials, Giilzow （GUL）, Vipperow （VIP） and Rostock （ROS）, were used to measure the topsoil inventories at the very b.ginning and after six （GUL）, seven （VIP） and ten （ROS） years of afforestation with fast growing trees. The effect on soil organic carb.n, plant availab.e nutrients, reaction, b.lk density, porosity and water conditions was analyzed, Arab.e soils without tree coppice were used as controls. Additionally, the endoand ectomycorrhizal colonization of two Salix and two Populus clones were investigated at one site （GUL） in 2002. The amounts of organic carb.n in the topsoil increased significantly （P 〈 0.01） presumab.y induced b. leaf and root litter and also b. the lack of tillage. The soil b.lk density significantly decreased and the porosity of the soil increased significantly （b.th P 〈 0.01）. The proportion of medium pores in the soil also rose significantly （P 〈 0.05 and 0.01）. Generally, afforestation of arab.e soils improved soil water retention. Ectomycorrhizas dominated the mycorrhizal formation of the Salix and Populus clones, with the accumulation of organic matter in the topsoil suspected of supporting the ectomycorrhizal formation. Thus, agroforestry with Salix and Populus spp. conspicuously affected chemical and additionally physical properties of the top layer of camb.sols within a period of six years.

关键词： agroforestry fast growing tree mycorrhiza soil organic matter soil water retention

A new record of cleantioides emarginata Kwon & Kim, 1992 (crustacea, Isopoda, Valvifera) from changjiang River estuary, china

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chinese Journal of Oceanology and Limnology 2013年第3期31卷 625-631页

作者：刘文亮 Gary c. b. POORE The State Key Lab.ratory of Estuarine and coastal Research East China Normal University Museum Victoria GPO Box 666Melbourne

Ab.tract At present, descriptions of cleantioides emarginata Kwon ＆ K/m, 1992 have b.en limited to the type locality of Pusan, In this study, we discovered this species in the changjiang （Yangtze） River estuary, china. This represents an extension of the known geographical range of c. emarginata. In addition, we present information of a colour pattern not previously describ.d, along with details on the estuarine hab.tat of the species.

关键词： Isopoda Valvifera new record estuarine species chinese waters

Approach for electrodynamic force for compensation in low voltage circuit b.eaker WP 630-1.2 type

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第3期8卷 393-396页

作者： LU na XU L.J Miedzifiski b Automation School Beijing University of Posts and Telecommunications Beijing 100876 China Electrical Power Engineering Institute Wroclaw University of Technology Wroclaw Poland

Undesirab.e repulsive force b.tween contact memb.rs due to b.th a current path shrink near a real contact area and/or so-called pinch effect is particularly onerous for power switch applications, and results in either contact floating or b.uncing which are associated with an electric arc following contact welding. This prob.em is of great importance for any circuit b.eaker especially for compact low voltage vacuum circuit b.eakers. To avoid contact floating at closure and during any inrush current under short circuit conditions, the electrodynamic repulsive force can b. employed successfully if we use a special compensation system flexib.y comb.ned with the contact itself. However to select and design the compensation system properly, its efficiency has to b. known. This paper presents an approach to ob.ain the electrodynamic force value depending on different shaped (rectangular, square, circle and arch) copper plates used in the compensator b. using ANSYS for current values 40 kA RMS. curve-fitting was done according to the calculating results, the optimization designing of compensation unit is b.sed on them.

关键词： compensation. Electrodynamic force. FEM (Finite Element Method)

Asphaltene Erosion Process in Air Plasma: Emission Spectroscopy and Surface Analysis for Air-Plasma Reactions

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Plasma Science and Technology 2012年第4期14卷 303-311页

作者： H.MARTINEZ O. FLORES J.c. POVEDA b. cAMPILLO Institute of Physical Sciences Autonomous National University of Mexico chemistry Faculty Autonomous National University of Mexico

Optical emission spectroscopy （OES） was applied for plasma characterization during the erosion of asphaltene sub.trates. An amount of 100 mg of asphaltene was carefully applied to an electrode and exposed to air-plasma glow discharge at a pressure of 1.0 Torr. The plasma was generated in a stainless steel discharge chamb.r b. an ac generator at a frequency of 60 Hz, output power of 50 W and a gas flow rate of 1.8 L/min. The electron temperature and ion density were estimated to b. 2.15±0.11 eV and （1.24±0.05）× 10^16 m^-3, respectively, using a doub.e Langmuir prob.. OES was employed to ob.erve the emission from the asphaltene exposed to air plasma. b.th molecular b.nd emission from N2, N2＋, OH, cH, NH, O2 as well as cN, and atomic light emission from V and Hγ were ob.erved and used to monitor the evolution of asphaltene erosion. The asphaltene erosion was analyzed with the aid of a scanning electron microscope （SEM） equipped with an energy dispersive X-ray （EDX） detector. The EDX analysis showed that the time evolution of elements c, O, S and V were similar and the chemical composition of the exposed asphaltenes remained constant. Particle size evolution was measured, showing a maximum size of 2307 μm after 60 min. This b.havior is most likely related to particle agglomeration as a function of time.

关键词： asphaltene erosion surface analysis optical emission spectroscopy pulsedplasma glow discharge