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ANALYSIS OF THE REFERENCE MATERIAL NBS-123 AND THE atomic WEIGHT OF SULFUR

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Chinese Science Bulletin 1989年第13期34卷 1086-1089页

作者：张青莲丁悌平 Department of Chemistry Pekin& University Beijing Institute of Mineral Deposits Academy of Geological Science Beijing

As Dr. Barnes of the National Bureau of Standards, USA, wishes us to check the isotopic composition of the reference material NBS-123, sphalerite with known δ34S=17.32±0.12‰ vs CDT （tentative）, Canyon Diablo trio... 详细信息

关键词： sulfur isotopes reference material atomic weight

Investigation of Phase Behavior and Domain Structure of Phospholipid Monolayers by atomic Force Microscopy

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Chinese Science Bulletin 1994年第24期39卷 2076-2080页

作者：杨晓敏肖东肖守军陆祖宏韦钰 Laboratory of Molecular and Biomoiecular Electronics Southeast University Nanjing 210018 PRC

The study of phase behavior and domain structure of Langmuir-Blodgett monolayers has been a subject of considerable interest since the *** phospholipid monolayers, in addition to their biological significance, are used as ideal systems suited for this *** the air/water interface the phase states of phospholipid monolayers and phase transitions, such as the domain growth in the coexistence re-

关键词： Langmuir-Blodgett monolaycr phase behavior domain atomic force microscopy (AFM).

Structural observation of CdSt_2 LB films and nanometer scale lithography by atomic force microscopy

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Chinese Science Bulletin 1995年第10期40卷 845-849页

作者：杨晓敏韦钰 State Key Laboratory of Molecular and Biomolecular Electronics Southeast University Nanjing 210018 China

Langmuir-Blodgett (LB) films and related thin organic films have been the objects ofincreasing technological and scientific interest over the past 20 years. Optimization of themacroscopic physical properties of these systems requires a detailed understanding of theirstructure-property retations on microscopic scale, including the structure of transferred

关键词： atomic force microscopy LB film nanometer scale lithography.

THE SQUARE-ROOT FORMULA FOR O-17 ABUNDANCE AND THE atomic WEIGHT OF OXYGEN

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Chinese Science Bulletin 1989年第10期34卷 828-831页

作者：张青莲 Department of Chemistry Peking University

Aside from the approximate analysis for 17O by mass spectrometry in the early 1930s, precise measurement was begun by Nier in 1950, but he calibrated his mass spectrometer with enriched argon isotopes for the inlet ga... 详细信息

关键词： oxygen 17O abundance atomic weight.

THE atomic WEIGHT OF ANTIMONY

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Science China Chemistry 1989年第12期32卷 1409-1414页

作者：张青莲钱秋宇赵墨田 Department of Chemistry. Peking University Beijing 100071 PRC National Research Center for Certified Reference Materials Beijing 100013. PRC

With enriched antimony isotopes of 99.224 atom% ^(121)Sb and 99.528 atom% ^(123)Sb, twotracer solutions were prepared, whose antimony content was ascertained by the isotopicdilution analysis utilizing an accurately assayed laboratory standard. Mass spectrometricmeasurements were made on a Finnigan MAT- 261 instrument to find the ratio of masses121 and 123. Five synthetic mixtures formed from the tracers served to determine thecorrection factor of mass discrimination. The isotopic abundances thus found for the anti-mony in the mineral stibnite together with the known nuclidic masses yield an accurateatomic weight of antimony as 121 .7575± 0 .0009.

关键词： antimony atomic weight isotopic abundance mass spectrometer

POTENTIAL-DERIVED atomic MULTIPOLE DISTRIBUTION

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Chinese Science Bulletin 1991年第3期36卷 201-205页

作者：孔静严继民 Institute of Chemistry Academia Sinica Beijing 100080 PRC

Ⅰ. INTERMOLECULAR INTERACTIONS AND atomic MULTIPOLE DISTRIBUTIONSThe intermolecular electrostatic interaction between the charges in two interacting molecules plays an important role in intermolecular interactions, especially in hydrogen-bonded complexes and charge-transfer complexes. Charge distribution in a molecule can be inter-

关键词： atomic multipoles potential-derived method ab initio calculation charge distribution in molecules.

Problems on Hybridization of Carbon atomic Orbitals in C_(60) Molecules

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Chinese Science Bulletin 1993年第11期38卷 916-919页

作者：陈琼王成瑞 Department of Chemistry Wuhan UniversityWuhan 430072 PRC

Since the stable C60 and C70 carbon clusters with macroscopic quantity were prepared and separated successfully in laboratory, the studies of the new molecule have aroused great attention. Investigation has been conducted on such elementary carbon polyhedrons from various angles and some achievements have been obtained. As far as the structure of the C60 molecules is concerned, H. W. Kroto et al. proposed that it is of a thirty-

关键词： elementary carbon polyhedron C60 molecule atomic orbital hybridization.

A Study of atomic Time Scale Stability

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Science China Mathematics 1993年第6期36卷 729-737页

作者：卫国 Shaanxi Observatory Academia Sinica Lintong 710600 PRC

The principle of System Clock in time scale is presented and some related propositions are proved in this paper based on the analysis of atomic clock noise characteristics. The purpose is to provide a new theoretical frame for the analysis of time scale algorithm. Under the principle, the classical weighted average methodology is discussed and some drawbacks of the methodology, which cannot be overcome by themselves, have been pointed out. Also, a new algorithm of time scale is proposed by means of the dynamic model of atomic clock, and the simulation on computer is carried out.

关键词： atomic time time and frequency frequency stability noise model

INVESTIGATION ON ELECTROSTATIC INTERACTION BETWEEN NH_3 AND HF USING CUMULATIVE POTENTIAL-DERIVED atomic MULTIPOLE METHOD

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Chinese Science Bulletin 1992年第12期37卷 993-996页

作者：孔静严继民 Institute of Chemistry Academia Sinica Beijing 100080 PRC

As a substantial part of the intermolecular forces, the electrostatic energy plays an important role in the formations of hydrogen-bonded and charge-transfer complexes and the properties of bio-and pharmic molecules. Among the various atomic parameter methods to calculate the electrostatic energy, the potential-derived atomic charge method (abbreviated PDAC) seems fruitful and is being paid great attention

关键词： ab initio calculations intermolecular interactions potential-derived method atomic multipole moments