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DFT Calculation of Room Temperature Ionic Liquid 1-Ethyl-3-Methyl-Imidazolium Chlorocuprate (Ⅰ)

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china Petroleum Processing & Petrochemical Technology 2008年第1期10卷 55-62页

作者： Lü Renqing Cao Zuogang (College of chemistry and chemical {2., china university of Petroleum (East china), Dongying 2.7061) College of chemistry and chemical {2. China University of Petroleum (East China) Dongying 257061 China

The density functional theory （DFT） has been employed to investigate the electronic structures ofEMIM^＋（1-ethyl-3-methylimidazolium＋）, CuCl2.-, Cu2.l3^- and EMIM^＋-CuCl2.-, EMIM^＋-Cu2.l3^- pairs. Full optimization and frequency analyses of EMIM^＋, CuCl2.-, Cu2.l3^-, eight initial EMIM^＋-CuCl2.-, and six initial EMIM^＋-Cu2.l3^- geometries have been carried out using Gaussian-94 software-package at 6-3 I＋G （d, p） basis set level for hydrogen, carbon, nitrogen, chlorine atoms and the Hay-Wadt effective core potential for copper atoms. The electronic structures of the lowest energy of EMIM^＋-CuCl2.-, EMIM^＋-Cu2.l3^- pairs, single EMIM^＋, CuCl2.-, and Cu2.l3^- have been comparatively studied. The calculated results showed that the optimized EMIM^＋-CuCl2.- pair conformer of the lowest energy was five ring moiety parallel to CuCl2.- plane with a distance of around 3.5,A, while EMIM^＋-Cu2.l3^- pair conformer of the lowest energy was five ring moiety of EMIM^＋ perpendicular to Cu2.l3^- plane with a distance of around 3.0 ,A between terminal chlorine atoms and 5-ring plane of EMIM^＋. The cohesion between cation and anion is electrostatic interaction and C-H---Cl hydrogen bonds are reinforced by charge assistance. The frequency analyses suggested that all stationary points are minimum points because of absence of imaginary frequency. The low energy of interaction caused by bulky asymmetry of EMIM^＋, and charge dispersion of cation and anion give rise to low melting point of ionic liquids EMIM^＋-CuCl2.-, and EMIM^＋-Cu2.l3^- . The interaction energy caused by the distance between cations and anions was investigated by single point energy scan.

关键词： ionic liquid density functional theory 1-ethyl-3-methylimidazolium chlorocuprate (I)

A NOVEL INTERPRETATION OF CONCENTRATION DEPENDENCE OF VISCOSITY OF DILUTE POLYMER SOLUTION

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Chinese Journal of Polymer Science 2000年第1期18卷 57-67页

作者： Yan Pan Rong-shi Cheng College of Material Science and engineering, South china {2. of Technology, Guangzhou 510641, china College of chemistry and chemical engineering, Nanjing {2., Nanjing 2.0093, china S china Univ Technol Coll Mat Sci & Engn Guangzhou 510641 Peoples R China Nanjing Univ Coll Chem & Chem Engn Nanjing 210093 Peoples R China

The concentration dependence of the reduced viscosity of dilute polymer solution is interpreted in the light of a new concept of the self-association of polymer chains in dilute solution. The apparent self-association constant is defined as the molar association constant divided by the molar mass of individual polymer chain and is numerically interconvertible with the Huggins coefficient. The molar association constant is directly proportional to the effective hydrodynamic volume of the polymer chain in solution and is irrespective of the chain architecture. The effective hydrodynamic volume accounts for the non-spherical conformation of a short polymer chain in solution and is a product of a shape factor and hydrodynamic volume. The observed enhancement of Huggins coefficient for short chain and branched polymer is satisfactorily interpreted by the concept of self-association. The concept of self-association allows us to predict the existence of a boundary concentration C-s(dynamic contact concentration) which divides the dilute polymer solution into two regions.

关键词： self-association polymer solution viscosity concentration dependence

Colloidal organic carbon in Huanghe, Changjiang and Qiantang River

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Chinese Science Bulletin 1998年第11期43卷 915-917页

作者： WANG Jiangtao College of chemistry and chemical {2., Ocean university of Qingdao, Qingdao 2.6003, china Callege of chemistry and chemical {2. Ocean University of Qingdao Qingdao China

Cross-flow ultrafiltration techniques have been used to separate colloidal organic carbon (COC) from natural water, and COC in three water samples that were collected from Huanghe, Changjiang and Qiantang River was determined. On average, COC comprised about 68.6% of the total dissolved organic carbon. The abundance of COC suggested that COC could play important roles in input fluxes and biogeochemistry of organic carbon.

关键词： cross-flow ultrafiltration colloidal organic carbon.

Effect of Anodization on the Graphitization of PAN-based Carbon Fibers of PAN-based Carbon Fibers

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Journal of Wuhan university of Technology(Materials Science) 2011年第5期26卷 926-930页

作者：贺冬枚蔡青云 State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical EngineeringHunan University

One-step pretreatment,anodization,is used to activate the polyacrylonitrile （PAN）-based carbon fibers instead of the routine two-step pretreatment,sensitization with SnCl2.and activation with *** effect of the anodization pretreatment on the graphitization of PAN-based carbon fibers is investigated as a function of Ni-P *** PAN-based carbon fibers are anodized in H3PO4 electrolyte resulting in the formation of active sites,which thereby facilitates the following electroless Ni-P *** fibers in the presence and absence of Ni-P coatings are heat treated and the structural changes are characterized by X-ray diffraction and Raman spectroscopy,both of which indicate that the graphitization of PAN-based carbon fibers are accelerated by both the anodization treatment and the catalysts *** the anodized carbon fibers,the routine two-step pretreatment,sensitization and activation,is not needed.

关键词： anodization X-ray diffraction raman spectroscopy graphitization

Structures and stability of isomers of[C,N,N,P]system

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Science china chemistry 2005年第5期48卷 415-423页

作者： KAN Wei1,2. ZHONG Hua1, YU Haitao1, FU Honggang1,3 & SUN Jiazhong1,3 1. School of chemistry and Materials Science, Heilongjiang university, Harbin 150080, {2. 2. School of chemistry and chemical engineering, Qiqihar university, Qiqihar 161006, {2. 3. State Key Laboratory of Theoretical and Computational chemistry, Institute of Theoretical chemistry, Jilin university, Changchun 13002., {2. 1. School of chemistry and Materials Science Heilongjiang University 150080 Harbin China 2. School of chemistry and chemical {2. Qiqihar University 161006 Qiqihar China 3. Jilin university State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry 130023 Changchun China

Nine isomers, twenty transition states, and some relative dissociation fragments of [C,N,N,P] system were located at the B3LYP/6-311G(d) and QCISD(t)/6-311+G(2.f) (single-point) levels of theory, and the isomerization, structures, and stability of these obtained isomers were suggested. The results indicate that four nonlinear chainlike isomers NCNP, NCPN, CNPN, and CNNP with 2.′ electronic state are kinetically stable. Other isomers are kinetically unstable to-wards isomerization or dissociation because of the corresponding smaller reaction barriers. Furthermore, calculated vibrational frequencies, rotational constants, dipole moments, the first adiabatic ionization energies, and adiabatic electron affinities of the four isomers may provide some theoretical information that is helpful for identifying their existence in future laboratory and interstellar investigations. The results are also compared with [Si,N,N,P] system.

关键词： potential energy surface, [C,N,N,P] system, isomerization, kinetic stability.

Preparation of chemical manganese dioxide from manganese sulfate

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Mining Science and Technology 2010年第6期20卷 877-881页

作者： FU Jiangang, HE Zhangxing, WANG Hui, LIANG Wei, GUO Chao College of chemistry and chemical {2., Central South university, changsha 410083, china [a] College of chemistry chemical engineering Central South University Changsha 410083 China

chemical Manganese Dioxide （CMD） was prepared by an alkali-oxidation method. There are several virtues to this environmental friendly and clean process, including the nontoxic and harmless reagents and products, easy operations, no pollutants, easily obtained raw materials and moderate reaction conditions. The synthesized manganese dioxide was characterized by XRD and SEM. The particles were small, consisting primarily of α-MnO2.and γ-MnO2. Experimental results showed that the optimum conditions were： MnSOa.H2. to NaOH ratio, 1.0：2.4; catalyst concentration （catalyst TF-2., 6% of the MnSO4; initial solution pH, 11; reaction time and temperature, 2. min and 80 ℃; air flow, 0.2. m3/h; and, agitation rate, 700 r/rain. The conversion of MnSO4 can exceed 80% under these optimum conditions.

关键词： MnSO4 alkali-oxidation chemical manganese dioxide clean process

Polymer-assisted nanoparticulate contrast-enhancing materials

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Science china chemistry 2010年第3期53卷 479-486页

作者： DING Yin1,3,HU Yong2.WU Wei1 & JIANG XiQun1 1Laboratory of Mesoscopic chemistry and Department of Polymer Science and engineering,College of chemistry & chemical engineering,Nanjing university,Nanjing 2.0093,china 2.ational Laboratory of Solid State Microstructure,Department of Material Science and engineering,Nanjing university,Nanjing 2.0093,china 3Key Laboratory of Analytical chemistry for Life Science,Ministry of Education,School of chemistry and chemical engineering,Nanjing university,Nanjing 2.0093,china 1. Laboratory of Mesoscopic chemistry and Department of Polymer Science and engineering College of Chemistry & Chemical Engineering Nanjing University Nanjing 210093 China3. Key Laboratory of Analytical Chemistry for Life Science Ministry of Education School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China2. National Laboratory of Solid State Microstructure Department of Material Science and Engineering Nanjing University Nanjing 210093 China

The application of nanotechnology in medicine research has significant potential in modern biomedical research,disease diagnosis and *** fluorophore-based detection techniques have been widely used as imaging and signal transduction tools for the detection of trace levels of *** photosensitivity of the fluorophores,however,limits their application in such complex environments as living bio-systems where degradation or photobleaching *** nanoparticles have unique and stable optical,electrical,magnetic and catalytic properties because of their various shapes,sizes and *** potential of the nanoparticles as novel imaging agents has been studied as a possible solution to this *** modification of inorganic nanoparticles could enhance their biostability in physiological conditions and ability of targeting bioactive molecules.

关键词： contrast agent cell image gold nanoparticles iron oxide nanoparticles carbon nanotubes polymeric-inorganic hybrid nanoparticles

Electrochemical investigation on the formations of Dy-Ni alloy films in dimethylformamide

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Rare Metals 2002年第2期21卷 85-89页

作者： HE Fengrong, WANG Yu, LIU Guankun, and SA LichangSchool of chemistry and chemical {2., Zhongshan university. Guangzhou 5102.5, china School of chemistry and chemical {2. Zhongshan University Guangzhou 510275

The elexctrochemical properties of Dy (III), Ni(II) + Ni(II) indimethylformamide were studied by cyclic voltammetry on Pt or Cuelectrode. Black, metallic lustered, compact and well adhesive Dy-Nialloy films can be co-deposited on Cu electrode bysweeping-potential-deposition method within some potentials. SEM,EDAX and XRD were used to analyze the alloy films. The Dy content inthe Dy-Ni alloy film is up to 56.91/100 (mass fraction) and the Dy-Ni alloy films are amorphous.

关键词： Dy-Ni alloy film dimethylformamide (DMF) Sweeping-potential-deposition-method induced coi-deposition

Fluorometric enzyme immunosensing system based on natural product resveratrol for horseradish peroxidase and Ag/SiO_2.nanoparticles

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Science china chemistry 2008年第3期51卷 233-240页

作者： GONG FuChun, CAO Zhong, TAN ShuZhen, TAN YaFei & HE XiaoChun College of chemistry and Environmental engineering, {2. university of Science and Technology, {2. 410076, china 1. College of chemistry and Environmental engineering Changsha University of Science and Technology Changsha 410076 China

The properties of resveratrol (3′, 4′, 5-trihydroxystlbene, RST) were for the first time evaluated as a potential substrate for horseradish peroxidase (HRP)-catalyzed fluorogenic reaction. The properties of RST for use as fluorogenic substrates for HRP and its application in immunoassays were compared with commercially available substrates such as p-hydroxyphenylpropionic acid (pHPPA), chavicol and Amplex red by a fluoroimmunosensing method in the use of Schistosomia japonicum antibody (SjAb) as a model analyte. The fluoroimmunosensing device was constructed by dispersing Schistosomia japonicum antigen (SjAg), nano-Ag/SiO2.particles and sol-gel at low temperature. In pH 5.8 Britton-Robinson buffer (B-R), HRP-SjAb conjugates can catalyze the polymerization reaction of RST by H2.2.forming fluorescent dimmers. The increase of the fluorescence intensity of the dimmers product at emission of 462.nm (excitation: 315 nm) is proportional to the concentration of HRP-SjAb binding to the SjAg entrapped in the nano-Ag/SiO2.particles-sol-gel matrix. A competitive binding assay has been used to determine SjAb in rabbit serum with the aid of SjAb labeled with HRP. Substrate RST showed comparable ability for HRP detection and its enzyme-linked immunosensing reaction system, in a linear detection ranging of 1.5×10-6-7.3×10-4 g/L and with a detection limit of 1.5×10-6 g/L. The immobilized biocomposites surface could be regenerated by simply polishing with an alumina paper, with an excellent reproducibility (RSD = 4.7%). The proposed method has been successfully used for analysis of the rabbit serum sample with satisfactory results.

关键词： resveratrol HRP fluorogenic substrate Ag/SiO2 nanoparticles enzyme-linked immunosensing Schistosomia japonicum