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Experimental study of surface texture and resonance mechanism of booming sand

Science china Earth sciences 2007年第9期50卷 1351-1358页

作者： QU JianJun1, ZHANG KeCun1, SUN Bo2, JIANG ShengXiang3, DONG GuangRong1, ZU RuiPing1 & FANG HaiYan 1 Key Laboratory of Desert and Desertification, Cold and Arid Regions Environmental and Engineering Research institute, chinese academy of sciences, lanzhou 730000, china 2 Shanghai institute of Polar Regions, Shanghai 210000, china 3 lanzhou institute of chemical physics, chinese academy of sciences, lanzhou 730000, china Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Shanghai institute of Polar Regions Shanghai 210000 China lanzhou institute of chemical physics Chinese Academy of Sciences Lanzhou 730000 China

The sound-producing mechanism of booming sand has long been a pending problem in the blown sand physics. Based on the earlier researches, the authors collected some silent sand samples from Teng- ger Desert, Australian Desert, Kuwait Desert, beaches of Hainan Island and Japanese coast as well as the soundless booming sand samples from the Mingsha Mountain in Dunhuang to make washing ex- periments. In the meantime the chemical corrosion experiment of glass micro-spheres, surface coating experiment and SEM examination were also conducted. The experimental results show that the sound production of booming sand seems to have nothing to do with the presence of SiO2 gel on the surface of sand grains and unrelated to the surface chemical composition of sand grains but is related to the resonance cavities formed by porous (pit-like) physical structure resulting from a number of factors such as wind erosion, water erosion, chemical corrosion and SiO2 gel deposition, etc. Its resonance mechanism is similar to that of Hemholz resonance cavity. Under the action of external forces, nu- merous spherical and sand grains with smooth surface and porous surface are set in motion and rub with each other to produce extremely weak vibration sound and then become audible sound by human ears through the magnification of surface cavity resonance. However the booming sands may lose their resonance mechanism and become silent sand due to the damping action caused by the invasion of finer particles such as dust and clay into surface holes of sand grains. Therefore, clearing away fine pollutants on the quartz grain surface is an effective way to make silent sand emit audible sound.

关键词： booming sand, surface texture, quartz grain, sound-producing mechanism, Hemholz resonance cavity

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STRUCTURE TRANSITION OF MECHANICAL ALLOYING OF Mo AND Si POWDERS

STRUCTURE TRANSITION OF MECHANICAL ALLOYING OF Mo AND Si POW...

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21世纪重有色金属冶金高新技术及新材料国际会议

作者： Ma Qin, Zhang Jianbin and Yin Jie (Gansu University of Technology, lanzhou, china, 730050) Xue Qunji (lanzhou institute of chemical physics, chinese academy of sciences, lanzhou, china, 730000)

The solid-state reaction of Mo and Si mixed powders produced by the mechanical alloying (MA) was examined using differential thermal analyzer (DTA) and X-ray diffraction (XRD). XRD patterns presented herein suggested that the volume fraction of β-MoSi2 increased with increasing milling time. After milling for 5 h, a weaker diffraction line of (101) plane of hexagonal p-MoSi2 was observed, from 15 h to 50 h, the diffraction lines contributed by α-MoSi2 emerged and remained almost unchanged, but up to 163 h, α-MoSi2 peaks disappeared from the XRD pattern and DTA experiments found that there were two exothermic peaks.

关键词： STRUCTURE TRANSITION OF MECHANICAL ALLOYING OF Mo AND Si POWDERS

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Bioremediation of Oil Spills in Cold Environments: A Review

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Pedosphere 2009年第3期19卷 371-381页

作者： YANG Si-Zhong JIN Hui-Jun WEI Zhi HE Rui-Xia JI Yan-Jun LI Xiu-Mei YU Shao-Peng State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 （China） lanzhou institute of chemical physics Chinese Academy of Sciences Lanzhou 730000 （China） Department of Geography Harbin College Harbin 150086 （China）

Oil spills have become a serious problem in cold environments with the ever-increasing resource exploitation, transportation, storage, and accidental leakage of oil. Several techniques, including physical, chemical, and biological methods, are used to recover spilled oil from the environment. Bioremediation is a promising option for remediation since it is effective and economic in removing oil with less undue environmental damages. However, it is a relatively slow process in cold regions and the degree of success depends on a number of factors, including the properties and fate of oil spilled in cold environments, and the major microbial and environmental limitations of bioremediation. The microbial factors include bioavailability of hydrocarbons, mass transfer through the cell membrane, and metabolic limitations. As for the environmental limitations in the cold regions, the emphasis is on soil temperatures, freeze-thaw processes, oxygen and nutrients availability, toxicity, and electron acceptors. There have been several cases of success in the polar regions, particularly in the Arctic and sub-Arctic regions. However, the challenges and constraints for bioremediation in cold environments remain large.

关键词： bioremediation cold environments freeze-thaw processes frozen soils oil spills

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单取代Keggin型磷钼酸催化氧化环己烯合成反-1，2-环己二醇

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石油化工 2008年第5期37卷 497-501页

作者：解启慧王晓来中国科学院兰州化学物理研究所羰基合成与选择氧化国家重点实验室

以过渡金属离子(Fe3+,Co2+,Ni2+,Cu2+,Zn2+,V5+,Mn2+)取代的Keggin型磷钼酸为催化剂、30%(质量分数)的H2O2溶液为氧化剂,环己烯经催化氧化合成了反-1,2-环己二醇。考察了催化剂的种类和用量、反应温度、反应时间和H2O2用量对环己烯氧化... 详细信息

以过渡金属离子(Fe3+,Co2+,Ni2+,Cu2+,Zn2+,V5+,Mn2+)取代的Keggin型磷钼酸为催化剂、30%(质量分数)的H2O2溶液为氧化剂,环己烯经催化氧化合成了反-1,2-环己二醇。考察了催化剂的种类和用量、反应温度、反应时间和H2O2用量对环己烯氧化反应的影响。实验结果表明,Fe取代的Keggin型磷钼酸(H6PMo11FeO40)是环己烯氧化制反-1,2-环己二醇的高效催化剂。适宜的反应条件为:环己烯10mmol、n(H6PMo11FeO40)∶n(环己烯)=0.020、乙腈3mL、n(H2O2)∶n(环己烯)=1.5、反应温度55℃、反应时间8h。在此条件下,环己烯的转化率为98%,反-1,2-环己二醇的选择性为97%。用核磁共振及气相色谱-质谱联用仪对产物进行表征,结果显示产物为反-1,2-环己二醇。

关键词：单取代Keggin型磷钼酸催化氧化环己烯反-1,2-环己二醇过氧化氢

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钴氧化铝纳米有序阵列复合结构的光学特性研究

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物理学报 2004年第5期53卷 1594-1598页

作者：李燕王成伟田军刘维民陈淼力虎林西北师范大学物理与电子工程学院兰州730070 中国科学院兰州化学物理研究所固体润滑国家重点实验室兰州730000 兰州大学化学化工学院兰州730000

对采用电化学沉积工艺制备的Co AAO纳米线有序阵列复合结构的光反射和光吸收特性进行了研究 .UV VIS NIR光谱仪测试结果表明 ,增加氧化铝模板孔洞中纳米线的长度或直径 ,Co AAO纳米有序阵列复合膜的吸收边大幅度红移 (2 83— 398nm) ,... 详细信息

对采用电化学沉积工艺制备的Co AAO纳米线有序阵列复合结构的光反射和光吸收特性进行了研究 .UV VIS NIR光谱仪测试结果表明 ,增加氧化铝模板孔洞中纳米线的长度或直径 ,Co AAO纳米有序阵列复合膜的吸收边大幅度红移 (2 83— 398nm) ,可见至近红外波段反射率大范围可调 (70 %— 6 % ) ,实验发现这种变化更加敏感于直径 .这种复合结构体系具有直接带隙半导体的光学特性 .

关键词：多孔氧化铝模板吸收边调制反射率调制纳米有序阵列电化学沉积工艺直接带隙半导体

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Enantioseparation of Novel Chiral Tetrahedral Clusters on a Chiral Stationary Phase (CSP) by High Performance Liquid Chromatography

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色谱 2004年第4期22卷 329-330页

作者： WANG Xia~1, LI Wenzhi~2, LIU Chunhui~1, CHEN Liren~1, LI Yongmin~1(1. lanzhou institute of chemical physics, The chinese academy of sciences, lanzhou 730000, china 2. Chemistry and chemical Engineer College, Liaocheng University, Liaocheng 252059, china ) lanzhou institute of chemical physics Chinese Academy of Sciences Lanzhou 730000 China Chemistry and chemical Engineer Colleger Liaocheng University Liaocheng 252059 China lanzhou institute of chemical physics Chinese Academy of Sciences 342 Tianshui Road Lanzhou 730000 China

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Fabrication Patterned Polyaniline Films by Mircocontact Printing and Area-selective Electropolymerization

Fabrication Patterned Polyaniline Films by Mircocontact Prin...

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甘肃省化学会成立六十周年学术报告会暨二十三届年会

作者： Fei Guan, Jinqing Wang, Rui Zhang, Miao Chen (State Key Laboratory of Solid Lubrication, lanzhou institute of chemical physics, chinese academy of sciences, lanzhou 730000, PR china)

Patterned polyaniline (PANI) films was achieved by electrochemical polymerization in the aqueous monoaniline solution and microcontact printing with elastomeric poly(dimethysiloxane) (PDMS) stamps. Optical microscope, atomic force microscopy (AFM), lateral force microscopy (LFM) and X-ray photoelectron spectroscopy (XPS) was used to examine the topography and properties of patterned PANI films. Experimental resuLts show that the interfacial properties of surface control the rate of electrochemical polymerization, and the rate on the modified silicon surface is higher than that on the bare silicon surface. In addition, through controlling experimental conditions, we can obtain films surface with reguLar pattern, clear boundary and being completely covered by PANI.

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CO*/CO exchange on Pd(lll) at low temperature

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chinese Science Bulletin 1997年第3期42卷 215-218页

作者： FAN Taishan, CAO Yuming, LIU Xianchun, ZHAI RunshengGUO Xiexian, YU Changchun, ZHANG Bing and SHEN Shikong1 State Key Laboratory of Catalysis, Dalian institute of Chemistry physics, chinese academy of sciences, Dalian 116023, china 2 S’.ale Key Laboratory of OSSO, lanzhou institute of chemical physics, chinese academy of sciences, lanzhou 730000, china

ADSORPTION and desorption are basic steps in catalytic reaction. The desorbing rate under a gas phase is faster than that in vacuum. This phenomenon has been studied extensively since its discovery. Study of this phen... 详细信息

关键词： adsorption desorption exchange.

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箭叶橐吾挥发油化学成分的研究

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天然产物研究与开发 2003年第3期15卷 224-226页

作者：李莉汪汉卿中科院兰州化学物理研究所兰州730000

运用气相色谱质谱计算机联用技术 ,结合标准谱库 ,对青海产箭叶橐吾的挥发油成分进行了研究 ,分离鉴定了 39个化合物 ,主要成分为 2 甲基丁烯酸 (5 0 0 1% )、顺 β 松油醇 (2 0 82 % )、反 β 松油醇 (4 0 6 9% )、4 甲基 1... 详细信息

运用气相色谱质谱计算机联用技术 ,结合标准谱库 ,对青海产箭叶橐吾的挥发油成分进行了研究 ,分离鉴定了 39个化合物 ,主要成分为 2 甲基丁烯酸 (5 0 0 1% )、顺 β 松油醇 (2 0 82 % )、反 β 松油醇 (4 0 6 9% )、4 甲基 1 异丙基 R 3 环己烯 1 醇 (15 4 6 7% )、十二烷 (2 181% )、十四烷 (2 2 76 % )、Tau . Muurolol(3 10 8% )、α 杜松醇 (5 6 82 % )、十六醛 (2 2 6 6 % )、6 ,10 ,14 三甲基 2 十五烷酮(3 4 2 1% )、三十烷 (2 370 % )、二十五烷 (3 76 6 % )等。

关键词：箭叶橐吾挥发油化学成分气相色谱-质谱-计算机联用技术菊科

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HYDROGEN DISPLACEMENT OF CHEMISORBED CO FROM THE Ni(100) SURFACE

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分子催化 1990年第S1期4卷 49-60页

作者： Shen Shikong(lanzhou institute of chemical physics, chinese academy of sciences, lanzhou 730000. china)John L. Gland (Corporate Research, Exxon R. & E. Co., Annandale, NJ 08801)Dan A. Fisher (NSLS-Brookhaven National Lab., Upton, NY 11973)Francisco Zaera (Chemistry Dept., University of California/ Riverside, CA 92521)

We report the first observation of hydrogen induced displacement of chemisorbed CO from the Ni（100） surface. This displacement is unexpected since the heat of adsorption for CO is 126 kJ/mole, about 30 kJ/mole larger than the 96 kJ/mole heat of adsorption for hydrogen, Rates of displacement were measured by Fluorescence Yield Near Edge Spectroscopy （FYNES） and Temperature Programmed Desorption （TPD）. Excellent agreement is observed between both methods. Hydrogen pressures in the 10-4 to 10-1 Torr range cause displacement of chemisorbed CO in the 270 to 330 K temperature range in a matter of minutes. The displacement reaction is clearly positive order in CO coverage. The CO coverage data suggested two first order reaction regions with a decrease in rate with decreasing coverage. Displacement is about half order in hydrogen pressure. The activation energy for the high coverage displacement rate is approximately 29±4 kJ/mole while the activation energy for the low coverage displacement rate about

关键词： coverage SURFACE unexpected minutes adsorbed instead decreasing clearly collision desorption

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