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Chinese Science Bulletin 2001年第15期46卷 1317-1320页

作者： Yang, QH Li, f Hou, PX Liu, C Liu, M Cheng, hm Chinese Acad Sci Inst Met Res Shenyang 110015 Peoples R China

Precise evaluation of innerdiameter distribution of open carbon nanotubes (CNTs) is the basis of systematic investigation of physico-chemical processes occurring in nano-sized quasi-1-dimensional carbons. Due to the porosity characteristics and adsorption properties, this study evaluated the innerdiameter and its distribution of carbon nanotubes by analyses of nitrogen cryo-adsorption isotherms, and proved that the gas adsorption method is an effective method to characterize the inner cavity structure in comparison with that of electron microscopy observations and Raman measurements. The advantages of this method are as follows: firstly, statistical information for innerdiameter distribution of open nanotubes can be obtained; Secondly, the method based on the adsorption process in inner cavities is of importance for investigation of other physico-chemical pro- cesses inside the cavities of carbon nanotubes. And finally, if combining with other characterization methods, complete structural information

关键词： carbon nanotubes (CNTs) innerdiameter distribution gas adsorption method adsorption isotherm.

ELASTIC WAVES IN 3-D DISCRETE GRIDS

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Acta Mechanica Solida Sinica 1995年第4期8卷 283-293页

作者： Guan, hm Liao, ZP INST ENGN MECH HARBIN 150080PEOPLES R CHINA

Wave motion in finite element models presents some characteristics different from those of wave motion in continuum, which leads to the errors and other special phenomena in finite element simulation of wave motion. The wave propagation in a 3-D finite element model is studied by utilizing the formal solution in the paper, and the corresponding dispersion relations are derived. Then the main properties of wave motion in 3-D grids such as dispersion, cut-off frequency and polarization drift are discussed. Characteristics different from those of wave motion in 2-D grids are revealed.

关键词： finite elements discrete grids 3-dimensional wave motion

Ab initio Study on the Molecular Geometry, Electronic Structure and Thermodynamic Properties of Benzotrifuroxan(BTf)

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Chinese Journal of Structural Chemistry 1999年第2期18卷 49-55页

作者： Gong, XD Xiao, hm Dong, HS Nanjing Univ Sci & Technol Dept Chem Nanjing 210094 Peoples R China China Acad Engn Phys Inst Chem Mat Mianyang 610003 Peoples R China

The molecular geometries and electronic structures of two isomers of benzotrifuroxan (BTf) have been studied using ab initio molecular orbital method at the Hf/6 31G * level. The calculated results show that the hexanitroso isomer has much higher energy than the tetracyclic form and is unstable. Infrared frequencies have been calculated for the stable tetracyclic structure and scaled by 0.89. The scaled frequencies agree well with the available experimental results, and have been used to derive the standard thermodynamic functions, heat capacity( Cp °), entropy( S °) and enthalpy( H° H 298 °).

关键词： benzotrifuroxan(BTf) ab initio MO method molecular geometry electronic structure IR frequency thermodynamic property

A Whitecap Coverage Model Based on the Surface Slope for Criterion of Wave Breaking

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China Ocean Engineering 1998年第1期13卷 73-85页

作者： Xu, DL Yu, DY Lu, hm Ocean Univ Qindao Phys Oceanog Lab Qingdao 266003 Peoples R China Ocean Univ Qindao Sch Engn Qingdao 266003 Peoples R China

Using the limit surface slope as a criterion of wave breaking, a simple model for estimating the spatial fraction of breaking surface of sea at an instant, which is regarded as the whitecap coverge in this paper, is analytically derived from the probability density of surface slope based on Gaussian statistics. The resulting fraction is found depending on the fourth moment of wave spectum, m(4), as well as the critical threshold of surface slope. By expressing the fourth moment in terms of the Neumann spectrum, a formula linking the fraction and wind speed for fully developed sea states is obtianed. Another formula relating the fraction to both wind speed and fetch (or duration) is achieved by expressing m, in terms of the Krylov spectrum and applying the empirical relationships used in the SMB ocean wave predicting technique. A comparison between these results and the field data of whitecap coverage collected by Monahan and O'Muircheartuigh shows an encouraging agreement.

关键词： whitecap coverage criterion of wave breaking wind speed wind fetch wind duration fully developed sea state fetch-limited sea state

Proton transfer across conducting polypyrrole membrane separated by two electrolyte solutions

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Chinese Journal of Chemistry 1997年第5期15卷 410-416页

作者： Wang, hm Yu, ZM Wang, EK Chinese Acad Sci Changchun Inst Appl Chem Electroanalyt Chem Lab Changchun 130022 Jilin Peoples R China

Electrochemical behavior of the transfer of H+ across polypyrrole membrane (PPM) was studied. The transfer process was quasi-reversible and mainly diffusion-controlled. PPM electropolymerized in water solution has better reversibility than that in CH3CN solution for the transfer of H+. The transfer process of H+ across the two kinds of PPM indicated that the PPM electrochemically polymerized was of asymmetry.

关键词： polypyrrole membrane proton transfer electrochemical polymerization

Spectral Characteristics of Wind-Waves in Laboratory

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China Ocean Engineering 1998年第2期13卷 183-190页

作者： Lu, hm Xu, DL Yu, DY Ocean Univ Qingdao Phys Oceanog Lab Qingdao 266003 Peoples R China Ocean Univ Qingdao Coll Engn Qingdao 266003 Peoples R China

Spectral characteristics of wind-generated waves in labortaory are presented on the basis of a systematic measurement in a large-scale wind-wave channel and compared with those in the field. A marked characteristics of the measured spetra is the existence of secondary spectrum-peak. The dependence of spectral peak-frequency, peak-value and zeroth-order moment on wind speed and fetch are presented and found roughly similar to those in the field represented by the JONSWAP spectrum, regardless of the differences in coefficient. The spectral slope beta at high-frequencies are found somewhat greater than those of field wind-waves in both cases of deep and shallow waters. Except for the low-frequency part, the spectral forms measured in different wind conditions are similar and fit for the JONSWAP spectrum with gamma = 6 and beta = 5.5. Some relevant problems are discussed.

关键词： wind-wave channel spectral characteristics JONSWAP spectrum

Studies on monodispersed colloidal particles of doped yttrium compounds

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Chinese Journal of Chemistry 1995年第3期13卷 199-206页

作者： DENG, hm XU, Y GU, YD fudAN UNIV ANAL & MEASUREMENT RES CTRSHANGHAI 200433PEOPLES R CHINA fudAN UNIV DEPT CHEMSHANGHAI 200433PEOPLES R CHINA

Monodispersed particles of doped yttrium basic carbonates were prepared at aging at elevated temperature corresponding salts solutions in the presence of urea. Coprecipitation in mixed solutions of yttrium, lanthanum and neodymium salts under similar experimental conditions yielded composite particles of basic carbonates. The content of the three metals in the solids followed closely the initial composition of the reacting solutions. On calcination all prepared solids converted to their corresponding oxides while retaining their particle morphology. The so-prepared powders were characterized by various techniques.

关键词： YTTRIUM COMPOUNDS MONODISPERSED PARTICLES UREA DECOMPOSITION

Localization of tPA and PAI-1 mRNA in rat testis

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Chinese Science Bulletin 1997年第7期42卷 588-592页

作者： Zhou, hm Liu, YX CHINESE ACAD SCI INST ZOOLSTATE KEY LAB REPROD BIOLBEIJING 100080PEOPLES R CHINA

THE physiological function of tPA and PAI-1 in rat and monkey ovulation has been previously documented. In order to elucidate the function of tPA and PAI-1 in spermatogenesis, we have studied expression of tPA and PAI... 详细信息

关键词： tPA PAI-1 spermatogenesis in situ hybridization.

Study on the Asymmetrical Cold Rolling of Strip under Large Width to Thickness Ratio

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Journal of Materials Science & Technology 1996年第3期12卷 232-234页

作者： Liu, hm Lian, JC Duan, ZY Yanshan University Qinhuangdao 066004 China

On the condition of the width to thickness ratio 625 of rolled strip, the asymmetrical cold strip rolling process about the width center is studied by using computer numerical simulation method and experimental method. The simulated results of the transverse distributions of the rolling pressure, the 2-directional frictions and the front and back tensions agree with the experimental results well. It is an important discovery that the rolling pressure has three peak values across the strip width on the condition of large width to thickness ratio.

关键词： Study on the Asymmetrical Cold Rolling of Strip under Large Width to Thickness Ratio

STERIC　EffECT　Of　HYDROXY　GROUPS　ORTHO　TO　THE　AZO－GROUP　ON　ANalYTICal　BEHAVIOR　Of　CHROMOGENIC　REAGENTS

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Chinese Chemical Letters 1996年第3期7卷 275-278页

作者： Ma, hm Huang, YX Liang, SQ CHINESE ACAD SCI INST CHEMBEIJING 100080PEOPLES R CHINA

Three new azo-reagents having different numbers of hydroxy groups ortho to the azo-group, i.e.,2-(2', 4', 6'-trihydroxyphenylazo) -, 2-(2', 4'-dihydroxyphenylazo)- and 2-(4'-hydroxyphenytaro)benzenearsonicacid. were synthesized. Through comparative studies on the reactions of the three reagents with vinous metalions, especially with iron(III), it was found that not only selectivities but also sensitivities of azo-reagents canbe improved by utiltting rationally the steric effect of groups ortho to the azo-group. The reasons for theimprovements were discussed.

关键词： ORGANIC ANalYTICal REAGENTS fUTURE-STATUS