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Friction-reducing and antiwear behavior of metal halide-stabilized linear phosphazene derivatives as lubricants for a steel-on-steel contact

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Science china(Technological Sciences) 2005年第3期48卷 282-291页

作者： ZHU Jiamei 1,2 , LIU Weimin 2 & LIANG Yongmin 2 1. School of Chemical Engineering and Technology, china University of Mining and Technology, Xuzhou 221008, china 2. State Key Laboratory of Solid Lubrication, lanzhou institute of Chemical Physics, Chinese Academy of Sciences, {4., china 1. School of Chemical Engineering and Technology China University of Mining and Technology 221008 Xuzhou China 2. State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences 730000 Lanzhou China

A series of novel metal halide-stabilized linear phosphazene derivatives were synthesized. The friction-reducing and antiwear abilities of the resulting products as the lubricants for a steel-on-steel contact were comparatively investigated on an Optimol SRV oscillating friction and wear tester. The morphology of the worn steel surface was observed on a scanning electron microscope, while the chemical states of some typical elements on the worn steel surface were examined by means of X-ray photoelectron spectroscopy. It was found that both the side branch structures and central metals influenced the friction-reducing and antiwear behaviors of the synthetic derivatives as the lubricants, which was related to the different adsorption activities of the organic compounds composed of different organic ingredients and metallic ions on a nascent metal surface. All the synthetic lubricants except for the iron (III) derivative showed increased antiwear abilities with increasing metallic ionic radius. A protective layer originated from the tribochemical reaction together with the adsorbed boundary lubricating layer containing organic fluorine compounds, nitrogen oxide, and Fe 3 (PO 4.) 2 plays an important role in improving the friction and wear behavior of the steel-on-steel system.

关键词： metal halide-stabilized linear phosphazene derivatives,lubricant,steel,tribological properties.

Studies on SiO_2 Used for Antireflective and Protective Film

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稀有金属材料与工程 2011年第S4期40卷 246-248页

作者： Wang Jizhou,Wang Duoshu,Xiong Yuqing,Chen Tao Science and Technology on Surface Engineering Laboratory,lanzhou institute of Physics,lanzhou 730000,china lanzhou Inst Phys Sci & Technol Surface Engn Lab Lanzhou 730000 Peoples R China

The protective AR(anti-reflection) film of infrared wavelength is an important optical film used in army *** design and preparation of SiO2 film used for protection and avoiding-reflection in IR wavelength are discussed in this *** order to resolve the problem of water absorbing in 2900nm,we prepared the film by Ion Beam Assisted Deposition (IBAD) and annealed it after *** last,we get a good SiO2 film deposited on big spherical surface,which has very good optical and mechanical character.

关键词： optical film infrared AR film SiO2 rigidity

Entropy equilibrium equation and dynamic entropy production in environment liquid

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Progress in Natural Science:Materials International 2002年第3期12卷 22-26页

作者： HU Yinqiao(Cold and Arid Regions Environment and Engineering institute, Chinese Academy of Sciences, lanzhou 730000, china) Chinese Acad Sci Cold & Arid Reg Environm & Engn Inst Lanzhou 730000 Peoples R China

The entropy equilibrium equation is the basis of the nonequilibrium state thermodynamics. But the internal energy implies the kinetic energy of the fluid micelle relative to mass center in the classical entropy equilibrium equation at present. This internal energy is not the mean kinetic energy of molecular movement in thermodynamics. Here a modified entropy equilibrium equation is deduced, based on the concept that the internal energy is just the mean kinetic energy of the molecular movement. A dynamic entropy production is introduced into the entropy equilibrium equation to describe the dynamic process distinctly. This modified entropy equilibrium equation can describe not only the entropy variation of the irreversible processes but also the reversible processes in a thermodynamic system. It is more reasonable and suitable for wider applications.

关键词： nonequilibrium thermodynamics entropy equilibrium equation entropy production irreversible processes environ- ment liquid.

X-ray spectra induced in highly charged 4.Ar^q+ interacting with Au surface

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Science china(Physics,Mechanics & Astronomy) 2006年第2期49卷 203-212页

作者： ZHANG Xiao’an1,2, XIAO Guoqing1, YANG Zhihu1, CHEN Ximeng3, ZHAO Yongtao1, LI Fuli4. ZHANG Yinping1, CUI Ying3, ZHANG Hongqiang3, XU Xu3, SHAO Jianxiong3 & ZHAN Wenlong11. institute of Modern Physics, Chinese Academy of Sciences, lanzhou 730000, china 2. Department of Physics, Xianyang Normal University, Xianyang 712000, china 3. Department of Modern Physics, {4. University, lanzhou 730000, china 4. Department of Applied Physics, Xi’an Jiaotong University, Xi’an 71004., china 1. institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China 2. Department of Physics Xianyang Normal University Xianyang 712000 China 3. Department of Modern Physics Lanzhou University Lanzhou 730000 China 4. Department of Applied Physics Xi’an Jiaotong University Xi’an 710049 China

By use of optical spectrum technology, the spectra of X-ray induced by highly charged 4.Arq+ ions interacting with Au surface have been studied. The results show that the argon Kα X-ray were emitted from the hollow atoms formed below the surface. There is a process of multi-electron exciting in neutralization of the Ar16+ion, with electronic con-figuration 1s2 in its ground state below the solid surface. The yield of the projectile Kα X-ray is related to its initial electronic configuration, and the yield of the target X-ray is related to the projectile kinetic energy.

关键词： highly charged ion hollow multi-electron excitation X- ray.

The time and energy signals,counter plateau,energy resolution and gas gains performances of a new kind of micro-pattern gaseous detector-Micromegas

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Science china(Technological Sciences) 2008年第12期51卷 2208-2212页

作者： ZHANG XiaoDong1,2,YANG HeRun1,XU HuShan2,DUAN LiMin2,HU BiTao1,LI ChunYan2 & LI ZuYu2 1 School of Nuclear Science and Technology,lanzhou University,lanzhou 730000,china 2 institute of Modern Physics,Chinese Academy of Sciences,lanzhou 730000,china School of Nuclear Science and Technology Lanzhou University Lanzhou 730000 China institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China

In present paper,a new Micromegas detector is developed,and its time and energy signals are obtained in the figure *** rising time of fast time signal is less than 2 ns due to the very fast collection of avalanche electrons,and the rising time of the energy pulse is about 100 ns,which is corresponding to the total collecting time of the electrons and ions in the avalanche *** counter plateau,energy resolution and the gas gains of the detector have been compared with other groups' experimental results and the Garfield simulation result.

关键词： micro-mesh gaseous structure time and energy signals energy resolution gas gain counter plateau

Synthesis of 6-aryl substituted 3-(5'-phenyl-2H-tetrazole-2'-methylene)-S-triazolo[3,4.b]-1,3,4.thiadiazoles

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Chinese Journal of Chemistry 1995年第5期13卷 448-453页

作者： ZHANG, Zi-Yi ZOU, NingNational Laboratory of Applied Organic Chemistry, Department of Chemistry, lanzhou University, lanzhou, Gansu 730000, china National Laboratory of Applied Organic Chemistry Department of Chemistry Lanzhou University Lanzhou Gansu 730000 China

In this paper , 10 novel 6-aryl-3-(5'-phenyl-2H-tetrazole-2'-methylene)-S-triazolo[3, 4.b]-1,3,4.thiadiazoles have been synthesized by the condensation of 3-(5'-phenyl-2H-tetrazole-2'-methylene)-4.amino-5-mercapto-1,2,4.triazole with various aromatic carboxylic acids in the presence of phosphorus oxychloride. The structure of these compounds was determined by elemental analysis , UV, IR, 1H NMR and MS. Their spectral properties were also discussed.

关键词： S-triazolo[3,4.b]-1,3,4.thiadiazole synthesis spectral analysis

A high-resolution late Pleistocene record of pollen vegetation and climate change from Jingning, NW china

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Science china Earth Sciences 2006年第2期49卷 154-162页

作者： LI Chunhai12, TANG Lingyu1, FENG Zhaodong3,4. ZHANG Hucai2, WANG Weiguo3 & AN Chenbang3 1. Nanjing institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, china 2. Nanjng institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, china 3. Environment and Resources College, {4. University, lanzhou 730000, china 4. Beijing Normal University, Beijing 100875, china 1. Nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China 2. Nanjng institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China 3. Environment and Resources College Lanzhou University Lanzhou 730000 China 4. Beijing Normal University Beijing 100875 China

With the support of 18 AMS-14. data, a high-resolution pollen record from the Suancigou section at Jingning, Gansu Province was established. Our results showed that the vegetation ex-perienced a series of changes characterized by the alternative growth and decline of forest and steppe components during the period from 4..2 to 11 ka B.P. in the Jingning area. Over the period of 4.―29 ka B.P. (MIS3), coniferous forests were flourishing, indicating a humid climate with the tem-perature being lower than that of the present. Since 23 ka B.P., the vegetation was dominated by steppe-desert steppe under a cold and dry condition, and entered the Last Glacial Maximum domi-nated by desert steppe. Several periods of the marked decrease in the arborous pollen content in Suancigou well corresponded to the North Atlantic Heinrich events, especially to Heinrich event 3, further supporting that the Heinrich events were well reflected by the pollen record in the Loess Pla-teau as well.

关键词： Western Loess Plateau, pollen record, climatic change, late Pleistocene.

Magnetic characteristics of dustfall in urban area of north china and its environmental significance

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Science china Earth Sciences 2007年第11期50卷 1724-1732页

作者： XIA DunSheng1,2, YANG LiPing2, MA JianYing1, YU Ye1, WANG Guan2 & CHEN FaHu2 1 Key Laboratory of Desert and Desertification, institute of Cold and Arid Regions Environmental and Engineering, Chinese Academy of Sciences, lanzhou 730000, china 2 CAEP, Key Laboratory of West china’s Environmental System (Ministry of Education), {4. University, lanzhou 730000, china 1. Key Laboratory of Desert and Desertification Institute of Cold and Arid Regions Environmental and Engineering Chinese Academy of Sciences Lanzhou 730000 China 2. CAEP Key Laboratory of West China’s Environmental System (Ministry of Education) Lanzhou University Lanzhou 730000 China

Urban particulate pollutants not only affect urban air quality but also directly threaten public health. lanzhou has been one of the most seriously polluted cities in the world due to its special geophysical location and weather conditions, which makes it an ideal place for urban particulate pollution study. In this study a set of environmental magnetic parameters (χ_(1f),χ_(fd)%, χ_(ARM), SIRM, HIRM, SOFT and back field IRM) were measured and analyzed for the dustfall samples collected monthly during 1997.4.2000.5 and 2004.11—2005.10 at lanzhou University campus (KLD and CCS) and at a clear site of Gaolanxian (GLX). Results demonstrate that the main magnetic minerals in the dustfall are magnetite, with some maghaemite and haematite. Cross plots of M_(rs)/M_s vs. B_(cr)/B_c and χ_(fd)% vs. χ_(ARM)/SIRM indicate that the main magnetic grain sizes are pseudo-single-domain (PSD). The high concentration of magnetic minerals in the dustfall indicates that lanzhou is seriously polluted. The main pollution sources are anthropogenic activities and nature dust, with the former posing a great threat during the whole year, which is different from the general view that the natural dust is the main contributor in summer. With great efforts of the government and local authority in the past decades, the air quality in lanzhou has been improved in winter, but it is not so obvious in summer. This study also reveals that as a simple, rapid and accurate technology, environmental magnetism could be a valuable tool for urban pollution study.

关键词： environmental magnetism,dustfall,air pollution,lanzhou

Review of several problems on the study of eco-hydrological processes in arid zones

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Chinese Science Bulletin 2002年第5期47卷 353-360页

作者： ZHAO Wenzhi & CHENG GuodongCold and Arid Regions Environmental and Engineering Research institute, Chinese Academy of Sciences, lanzhou 730000, china State Key Laboratory of Frozen Soil Engineering, Chinese Academy of Sciences, lanzhou 730000, china Cold and Arid Regions Environmental and Engineering Research institute Chinese Academy of Sciences Lanzhou China State Key Laboratory of Frozen Soil Engineering Chinese Academy of Sciences Lanzhou China

Ecosystem degradation is a common and cardinal environmental problem in arid zones. The change in the eco-hydrological processes is the basic cause responsible for such a problem. The study on the eco-hydrological processes in arid zones has become a forefront and focus of the eco-environmental research. Recent studies on eco-hydrological processes in arid zones show that the primary vegetation pattern and its eco-hydrological effect are of the most stable state of the ecosystem in arid zones. Special water absorption ways of plants in arid zones and the hydraulic lift and reverse hydraulic lift functions of some plants are the key mechanisms to maintain the stability of the ecosystem in arid zones. In the case of water shortage, ensuring ecological water requirement and maintaining proper ecological ground- water table are the prerequisite to keep healthful operation of the ecosystem in arid zones. The paper reviews some advances in the study of eco-hydrological processes in arid zones. It puts

关键词： arid zone vegetation pattern eco-hydrological effect hydraulic lift plant water source ecological water requirement.