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Statistical theory for hydrogen bonding fluid system of A_aD_d type (I): The geometrical phase transition

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Science china chemistry 2006年第6期49卷 499-506页

作者： WANG Haijun1,2. HONG Xiaozhong3, GU Fang1 & BA Xinwu1 1. college of chemistry and Environment Science, Hebei {2., Baoding 071002. china 2. International Center for Materials Physics, Chinese Academy of Sciences, Shenyang 110016, china 3. college of Physics Science and Technology, Hebei {2., Baoding 071002. china 1. college of chemistry and Environment Science Hebei University Baoding 071002 China 2. International Center for Materials Physics Chinese Academy of Sciences Shenyang 110016 China 3. college of Physics Science and Technology Hebei University Baoding 071002 China

The influence of hydrogen bonds on the physical and chemical properties of hydrogen bonding fluid system of AaDd type is investigated from two viewpoints by the principle of statistical mechanics. In detail, we proposed two new ways that can be used to obtain the equilibrium size distribution of the hydrogen bonding clusters, and derived the analytical expression of a relationship between the hydrogen bonding free energy and hydrogen bonding degree. For the nonlinear hydrogen bonding systems, it is shown that the sol-gel phase transition can take place under proper conditions, which is further proven to be a kind of geometrical phase transition rather than a thermodynamic one. Moreover, several problems associated with the geometrical phase transition and liquid-solid phase transition in nonlinear hydrogen bonding systems are discussed.

关键词： hydrogen bonding fluid, equilibrium free energy, geometrical phase transition.

Study on the Separation of Co^(2.) from Zn^(2.) , Cd^(2.) by Anion-exchange Chromatography

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Journal of Central South university 2000年第2期12卷 88-91页

作者： WANG Xin yan,ZHOU Chun shan,WANG Yan (college of chemistry and {2. engineering, Central South university of Technology, Changsha 410083, china) 1. college of chemistry and {2. engineering Central South University of Technology 410083 Changsha China

The separation of Co 2. from Zn 2. , Cd 2. by anion exchange chromatography was discussed. The chromatographic column containing anion resin 2.1×7 which was saturated with a solution of ammonium chloride. The effects of the eluant acidity and eluant composition on the separation were investigated. The results indicate that this anion exchange chromatography is suitable to the separation of Co 2. from Zn 2. , Cd 2. , and the condition of separation is simple and convenient. When the column is saturated with NH 4Cl solution (2.0 mol/L, pH=4.0), the separation can be completed effectively. Zn 2. and Cd 2. can also be separa ted when different eluants are used and the pure solution with high concentration of Zn 2. , Cd 2. respectively can be obtained ea sily.

关键词： anion exchange chromatography Zn 2. Cd 2. Co 2. separation

Stochastic resonance in surface catalytic oxidation of carbon monoxide induced by colored noise

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Science china chemistry 2004年第2期47卷 106-112页

作者： GONG Yubing1,2. HOU Zhonghuai1 & XIN Houwen1 1. Department of chemical Physics, university of Science and Technology of{2., Hefei 2.002.,{2. 2. Department of Physics, Yantai Teachers university, Yantai 2.402.,{2. 1. Department of chemical Physics University of Science and Technology of China 230026 Hefei China 2. Department of Physics Yantai Teachers University 264025 Yantai China

The dynamical behavior of surface catalytic oxidation reaction of Pt(110)/CO+O2.modulated by colored noise, under the condition of specific temperature, has been investigated when the partial pressure of CO gas is near the supercritical Hopf bifurcation point. By computer simulation the oscillation and stochastic resonance induced by colored noise are observed. The influences of the intensity and correlation time of colored noise on stochastic resonance are discussed. The range of sensitivity of the system to the environmental fluctuation is analyzed.

关键词： colored noise, stochastic resonance, surface catalytic reaction of Pt(110)/CO+O2. supercritical Hopf bifurcation, signal-to-noise ratio (SNR).

Synthesis of a novel centipede-like copolymer of styrene and methyl methacrylate

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Science china chemistry 2007年第2期50卷 253-257页

作者： LI AiXiang1 & LU ZaiJun2.1 School of Material Science and engineering,Shandong university of Technology,Zibo 2.5049,{2. 2.School of chemistry and chemical engineering,Shandong university,Jinan 2.0100,{2. 1. School of Material Science and engineering Shandong University of Technology Zibo 255049 China 2. School of chemistry and chemical {2.ing Shandong University Jinan 250100 China

A well-defined,A2.-type,centipede-like copolymer of styrene and methyl methacrylate(PS-PS-PMMA) was synthesized by the combination of living anionic polymerization and atom transfer radical polym-erization(ATRP) . The synthetic approach involves the coupling reaction of polystyrene(PS) backbone bearing 1,1-diphenylethene(DPE) pendant groups,produced by ATRP and Wittig reaction,with living polystyryllithium(PSLi) ,and subsequent polymerization of the resulting 1,1-diphenylmethyl anions with methy methacrylate. The centipede-like copolymer was characterized by 1H NMR,IR,SEC,SLS,and DSC measurements.

关键词： architecture atom transfer radical polymerization centipede-like copolymer coupling reaction living anionic polymerization

Changes of decay rates of radioactive ^(111)In and ^(32.P induced by mechanic motion

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Science china chemistry 2007年第2期50卷 170-174页

作者： HE YuJian1,QI Fei2.& QI ShengChu3 1 college of chemistry and {2. engineering,Graduate university of Chinese Academy of Sciences,Beijing 100049,china 2.No. 1,Gravenhurst Court,Gaithersburg,Md 2.878,USA 3 Department of Applied chemistry,Peking university,Beijing 100871,china 1. college of chemistry and {2. engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China 2. No. 1 Gravenhurst Court Gaithersburg Md 20878 USA 3. Department of Applied chemistry Peking University Beijing 100871 China

The changes of decay rates of radionuclide 111In(electron capture) and 32.(β decay) induced by exter-nal mechanic motion are studied. The results indicate that,in the external circular rotation in clockwise and anticlockwise centrifuge on Northern Hemisphere(radius 8 cm,2.00 r/min) ,the half life of 111In compared with the referred(2.83 d) is decreased at 2.83% and increased at 1.77%,respectively;the half life of 32. compared with the referred(14.2. d) is decreased at 3.78% and increased at 1.75%,respec-tively. When the clockwise and anticlockwise rotations increase to 4000 r/min,the half life of 111In is decreased at 11.31% and increased at 6.36%,respectively;the half life of 32. is decreased at 10.08% and increased at 4.34%,respectively. When the circular rotation is removed,the decay rates of 111In and 32. return back to the referred,respectively. It is found that the external circular rotations in clockwise and anticlockwise centrifuge selectively increased and decreased the decay rates of 111In and 32.,respec-tively,and the effects are strongly dependent on the strength of circular rotation. It is suggested that these effects may be caused by the chiral interaction.

关键词： circular rotation helical motion 111In 32. decay rate chirality

Efficient degradation of dye pollutants using dioxygen mediated by iron(Ⅱ) 2.2.-bipyridine loaded layered clay catalyst under visible irradiation

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Science china chemistry 2006年第5期49卷 407-410页

作者： CHENG Mingming1,SUN Zhenying1,2.MA Wanhong1,CHEN Chuncheng1,ZHAO Jincai1 & WANG Zhengping2.1. Laboratory of Photochemistry,Center for Molecular Science,Institute of chemistry,Chinese Academy of Sciences,Beijing 100080,{2. 2. Department of chemical engineering,Harbin engineering university,Harbin 150001,{2. 1. Laboratory of Photochemistry Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China 2. Department of chemical engineering Harbin Engineering University Harbin 150001 China

The organic-inorganic layered solid catalyst Fe(bpy)_3^(2.)-laponite was ableto photode-grade Rhodamine B (RhB) by activation of dioxygen under visible irradiation (λ > 42.nm), while the homogeneous aqueous solution Fe(bpy)_3^(2.) showed no photoactivity. The catalystcould be repeatedly used and retained its reactivity. The hybrid catalyst could be separated fromthe suspension by centrifugation or sedimentation. The TOC removal yield of RhB was *** oxygen species (ROS) formed during degradation was detected by EPR. A possible mechanismwas proposed on the basis of the experimental results.

关键词： laponite, Rhodamine B, molecular oxygen, visible light.

Detection of Prorocentrum donghaiense using sandwich hybridization integrated with nuclease protection assay

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Acta Oceanologica Sinica 2009年第2期28卷 121-126页

作者： CHEN Jie ZHEN Yu MI Tiezhu YU Zhigang college of Marine Life Science Ocean University of China Qingdao 266003 China college of Environmental Science and engineering Ocean University of China Qingdao 266100 China college of chemistry and {2. engineering Ocean University of China Qingdao 266100 China

Prorocentrum donghaiense is an important harmful algae bloom （HAB） causing creature in china＇s seas, and the conventional visual detection can not cope with long-term monitoring and highthroughput sampling projects. An assay for P. donghaiense with sandwich hybridization integrated with nuclease protection assay （NPA-SH） was established. Tests with mixed samples and spiked field ones confirmed its good specificity and sensitivity. The cell number of P. donghaiense correlated well with the optical density, and the regression equation is y=4× 10^- 6x＋ 0.694 9, in which x is the cell number, and y is the optical density, with r2.0.953 5. These results show that the NPA-SH method has good feasibility in the detection of P. donghaiense. Results of NPA-SH and microscopy are excellent for each sample. The NPA-SH method was a simple way in quantitative detection of P. donghaiense, and the whole process could be finished in about six hours, which provided a new approach in high-throughput sampling and long-term monitoring of P. donghaiense.

关键词： Prorocentrum donghaiense ribosomal RNA S1 enzyme sandwich hybridization integrated with nuclease protection assay (NPA-SH)

Pictet-Spengler condensation reactions catalyzed by a recyclable H^+-montmorillonite as a heterogeneous BrΦnsted acid

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Science china chemistry 2010年第3期53卷 561-567页

作者： WANG YuFeng,SONG ZhanBo,CHEN ChunXia & PENG JinSong Department of chemistry and chemical {2.ing,college of Science,Northeast Forestry university,Harbin 150040,china 1. Department of chemistry and chemical {2.ing College of Science Northeast Forestry University Harbin 150040 China

Catalytic performance of different cation-exchanged montmorillonite clays has been investigated in the Pictet-Spengler C-C bond forming reaction.H+-Montmorillonite was found to be a very efficient and reusable catalyst for the endo cyclization of β-phenylethylamine derivatives with aldehydes under solvent-free *** addition,an aqueous condensation version for the synthesis of tetrahydro-β-carbolines using the H+-montmorillonite catalyst has been *** these environmentally friendly processes,the use of organic solvents was avoided and the catalyst was recycled with maintenance of high catalytic activity.

关键词： heterogeneous catalysis catalyst recycling mesoporous materials green synthesis

Internal noise stochastic resonance in CO oxidation on nm-sized palladium particles

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Science china chemistry 2005年第5期48卷 395-401页

Based on a stochastic mesoscopic model, the influence of internal noise on the oscillatory kinetics of the catalytic oxidation of CO on nm-sized palladium particles is studied, using the chemical Langevin equations, Poisson approximation algorithm, and exact stochastic simulation algorithm. The reaction rate oscillations are of stochastic nature due to considerable internal noise in such mesoscopic systems. It is found that the performance of the stochastic oscillations undergoes a maximum with the variation of internal noise level for a given CO partial pressure, which demonstrates the occurrence of internal noise stochastic resonance. This phe-nomenon implies that optimal internal noise would favor the reaction rate oscillation of CO oxi-dation on nm particles. Such a phenomenon is robust to the change of external parameters, such as CO pressures.

关键词： nanometer-sized palladium particles, surface catalytic CO oxidation, internal noise, stochastic resonance, chemical Langevin equation.