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Science China Chemistry 1994年第11期37卷 831-841页

作者：赵井泉朱晋昌蒋丽金 Institute of Photographic Chemistry Academia Sinica

Based on the crystal structure data of C-phycocyanins from Mastigocladus Laminosus andAgmenellum Quadruplicatum,the energy transfer processes in the βsubunits and the monomers are simulat-ed by the use of computer simulation *** simulation results show that excitation energy cantransfer in both directions between any pair of chromophores,and furthermore,the transfer can take place intwo opposite directions for many times between a pair of *** certainly exists energy trans-fer between the two subunits in a *** dynamic nature of the energy transfer processes has ***,it is also indicated that a component obtained from mathematically fitting the experimentaldata cannot be equivalent to a physical process.

关键词： algae phycocyanins energy transfer computer simulation kinetics primary process photosynthesis

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TERMINATION AND TRANSFER OF THE CHAIN RADICALS IN THE POLYMERIZATION OF ACRYLONITRILE INITIATED BY VANADIUM(V)-THIOUREA REDOX SYSTEM

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Chinese Journal of Polymer Science 1990年第4期8卷 312-320页

作者：吴锦远杨超雄吴宇贤 Guangzhou Institute of Chemistry Academia Sinica

The dependence of the molecular weights on the concentration of reactants in the polymerization of acrylonitrile initiated by vanadium (V)-thiourea redox system has been investigated. It was found that the molecular weights of the polymer change nonlinearly with increasing concentrations of nitric acid and thiourea. Probably, the composition of the complexes exert a great influence on the chain initiation and termination. The reaction of 'complextermination' gives rise to the decrease of the molecular weights markedly while the concentrations of thiourea and vanadium (V)in the range from one to three molar ratios.

关键词： Acrylonitrile Vanadium-Thiourea redox system Polymerization kinetics Molecular weight Chain transfer Termination of radicals.

A Characterization of Achievable Patterns of the MN-Puzzle Problem

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Journal of Computer Science & Technology 1990年第3期5卷 266-274页

作者：杨红青 Institute of Computing Technology Academia Sinica

One important MN-puzzle problem is to find a sequence of up-down and right-left movements of the empty-cell so that a goal-pattern can be achieved from a given *** second problem is to characterize the totality of the goal-pattern from a given *** third problem is finding the fewest movements to achieve *** this paper,these problems will be completely solved.

关键词： A Characterization of Achievable Patterns of the MN-Puzzle Problem

A NOVEL COPOLYMER-BOUND CIS-DICARBONYLRHODIUM COMPLEX FOR THE CARBONYLATION OF METHANOL TO ACETIC ACID AND ACETIC ANHYDRIDE

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Chinese Journal of Polymer Science 1989年第3期7卷 219-224页

作者：袁国卿陈予英陈荣耀 Institute of Chemistry Academia SinicaBeijing

A series of porous microspheres of linear and ethylene diacrylate (M') cross-linked copolymers of 2-vinylpyridine (V) and methyl acrylate (M) reacted with tetracarbonyldichlorodirhodium to form a series of cis-dicarbonylrhodium chelate complex (MVRh and MVM 'Rh). They are thermally stable yet very reactive in the carbonylation of methanol to acetic acid, and of methanol-acetic acid mixture to acetic acid and acetic anhydride with a selectivity of 100% under relatively mild and anhydrous conditions.

关键词： Cis-dicarbonylrhodium cationic complexes Copolymer ligands Carbonylation of methanol to acetic acid and acetic anhydride

KINETIC STUDY OF CARBONYLATION OF METHANOL TO ACETIC ACID AND ACETIC ANHYDRIDE OVER A NOVEL COPOLYMER-BOUND CIS-DICARBONYLRHODIUM COMPLEX

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Chinese Journal of Polymer Science 1989年第3期7卷 225-231页

作者：陈予英袁国卿陈荣耀 Institute of Chemistry Academia Sinica Beijing

The kinetic study of carbonylation of methanol-acetic acid mixture to acetic acid and acetic anhydride over a cis-dicarbonylrhodium complex (MVM' Rh) coordinated with the ethylene diacrylate (M') crosslinked copolymer of methyl acrylate (M) and 2-vinylpyddine (V)shows that the rate of reaction is zero order with respect to both reactants methanol and carbon monoxide, but first order in the concentrations of promoter methyl iodide and rhodium in the complex. Polar solvents can accelerate the reaction. Activation parameters were calculated from the experimental results, being comparable to that of the homogeneous system. A mechanism similar to that of soluble rhodium catalyst was proposed.

关键词： Carbonylation of methanol Copolymer-bound cis-dicarbonylrhodium complex Kinetic study

KINETICS OF POLYMERIZATION OF ACRYLONITRILE INITIATED BY VANADIUM(V)-THIOUREA REDOX SYSTEM

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Chinese Journal of Polymer Science 1990年第4期8卷 302-311页

作者：吴锦远杨超雄吴宇贤 Guangzhou Institute of Chemistry Academia Sinica

The kinetics of polymerization of acrylonitrile (AN) initiated by quinquevalent vanadium (V^(5+))-thiourea (TU) redox system has been investigated in aqueous nitric acid in the temperature range from 30 to 50℃. The polymerization rate (R_p) can be expressed as follows: In the copolymerization of acryionitrile with methyl acrylate (MA), the reactivity ratios were found to be 1.0 and 1.1, respectively. The experimental observations suggest that the initiating species is probably a complex consisting of a central ion of Lewis acid-VO_2^+ and the ligands of Lewis bases-acrylonitrile, thiourea, and nitrate anions, while the initiating system in lower concentration, the polymerization of acrylonitrile does not occur if the thiourea is acidified prior to its reaction with quinquevalent vanadium. This indicates that the primary radicals (or the monomeric radicals in the present article) are produced by associated thiourea rather than isothlourea.

关键词： Vanadium (V)-thiourea redox system acrylonitrile polymerization kinetics

STUDY OF ACOUSTIC EMISSION DURING NON-ISOTHERMAL CRYSTALLIZATION OF POLYPROPYLENE

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Chinese Journal of Polymer Science 1990年第1期8卷 69-74页

作者：沈静姝徐端夫姚瑞刚刘瑞霞李大为 Institute of Chemistry Academia Sinica Beijing

In this paper we have presented the results of acoustic emission (AE) during non-isothemal crystallization of polypropylene (PP) melt with mean cooling rate 4℃/min, and discussed the effects of molecular weight (MW) on AE activity. It is shown that the amount of AE ring-down counts during whole crystallization of PP depends on the MW *** copious AE bursts have been observed at the late stage of PPcrystallization. AE bursts are caused by cracking, crazing and cavitation between spherulites and inside spherulites.

关键词： Acoustic emission Non-isothermal crystallization Polypropylene

TEXTURES OF ETHYL-ACETYL CELLULOSE MESOPHASE

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Chinese Journal of Polymer Science 1989年第1期7卷 83-89页

作者：黄勇李历生 Guangzhou Institute of Chemistry Academia Sinica

There was phase separation between the anisotropic and isotropic phases in the ethyl-acetyl cellulose/dichloroacetic acid cholesteric liquid crystalline solutions .The textures of mesophase varied with the concentration. The mesophases could form the disc-like texture, oily streaks texture and texture of domains gathered randomly. In the first two textures the layers of the ordered molecular chain were perpendicular to the slide surface and the axes of the helical structure were parallel to the slide surface.

关键词： Ethyl-acetyl cellulose phase separation mesophase texture helical structure

Idealization Second Quantization of Composite Particles

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Communications in Theoretical Physics 2001年第11期36卷 525-530页

作者： ZHOU Duan-Lu YU Si-Xia SUN Chang-Pu Institute of Theoretical Physics Academia SinicaBeijing 100080China Institute of Theoretical PhysicsAcademia SinicaBeijing 100080China Institute of Theoretical PhysicsAcademia SinicaBeijing 100080China

A practical method is developed to deal with the second quantization of the many-body system containing the composite *** our treatment,the modes associated with composite particles are regarded approximately as independent ones compared with those of unbound *** field operators of the composite particles thus arise naturally in the second quantization *** be emphasized,the second quantization Hamiltonian has the regular structures which correspond clearly to different physical processes.

关键词： second quantization,composite particles

Collision and Thermal History of Indian-Sundaland-Eurasian Plates as Implicated by 40Ar/39Ar Age Spectra of Granodiorites

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Acta Geochimica 1987年第1期6卷 33-43页

作者：戴谟朱炳泉张玉泉浦志平张前锋洪阿实 Institute of Geochemistry academia Sinica Institute of Geochemistry academia Sinica Institute of Geochemistry academia Sinica Institute of Geochemistry academia Sinica Institute of Geochemistry academia Sinica Institute of Geochemistry academia Sinica

40Ar/39Ar plateau ages of biotite, plagioclase, K-feldspar and hornblende from the Biluoxueshan andLincang plutons in the three-river area of Yunnan and the Quxu pluton in the Gandise belt of Xizangindicate that the three plutons were emplaced at 420, 234 and 43.4 Ma, respectively. Based on the study ofclosure temperatures and thermal histories, it is shown that the Lincang and Biluoxueshan plutonsexperienced the same thermodynamic event during 85-90 Ma, temporally representing the collisionbetween the Sundaland and Eurasian plates, and that the Quxu pluton was uplifted at a much faster rateduring 40-44 Ma（2.6 mm/a）, marking the collision between the Indian and Eurasian plates.

关键词： Ar Collision and Thermal History of Indian-Sundaland-Eurasian Plates as Implicated by