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Friction-reducing and antiwear behavior of metal halide-stabilized linear phosphazene derivatives as lubricants for a steel-on-steel contact

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Science china(Technological Sciences) 2005年第3期48卷 282-291页

作者： ZHU Jiamei 1,2., LIU Weimin 2.& LIANG Yongmin 2.1. school of chemical {2. and technology, china University of Mining and technology, Xuzhou 2.1008, china 2. State Key Laboratory of Solid Lubrication, Lanzhou institute of chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, china 1. school of chemical {2. and technology China University of Mining and Technology 221008 Xuzhou China 2. State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences 730000 Lanzhou China

A series of novel metal halide-stabilized linear phosphazene derivatives were synthesized. The friction-reducing and antiwear abilities of the resulting products as the lubricants for a steel-on-steel contact were comparatively investigated on an Optimol SRV oscillating friction and wear tester. The morphology of the worn steel surface was observed on a scanning electron microscope, while the chemical states of some typical elements on the worn steel surface were examined by means of X-ray photoelectron spectroscopy. It was found that both the side branch structures and central metals influenced the friction-reducing and antiwear behaviors of the synthetic derivatives as the lubricants, which was related to the different adsorption activities of the organic compounds composed of different organic ingredients and metallic ions on a nascent metal surface. All the synthetic lubricants except for the iron (III) derivative showed increased antiwear abilities with increasing metallic ionic radius. A protective layer originated from the tribochemical reaction together with the adsorbed boundary lubricating layer containing organic fluorine compounds, nitrogen oxide, and Fe 3 (PO 4 ) 2.plays an important role in improving the friction and wear behavior of the steel-on-steel system.

关键词： metal halide-stabilized linear phosphazene derivatives,lubricant,steel,tribological properties.

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An efficient chiral synthesis of (R)-N-[3-acetyl-4-(2.hydroxy-3-isopropylamino-propoxy)phenyl]-butanamide with high enantioselectivity

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Science china Chemistry 2009年第8期52卷 1216-1219页

作者： WANG NaiXing1,2.& TANG XinLiang1,3 1 Technical institute of Physics and Chemistry,Chinese Academy of Sciences,Beijing 100080,china 2.College of Chemistry and {2. engineering,Graduate University of Chinese Academy of Sciences,Beijing 100049,china 3.school of chemical engineering and environment,Beijing institute of technology,Beijing 100081,china 1. Technical institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100080 China 2. College of Chemistry and chemical engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China 3. school of chemical {2. and environment Beijing Institute of Technology Beijing 100081 China

R-Enantiomer of the β-receptor antagonist N-[3-acetyl-4-(2.hydroxy-3-isopropylamino-propoxy)phenyl] butanamide with high enantioselectivity was synthesized from cheap starting materials and enantiopure chiral reagent through an efficient,convenient and practical synthetic *** product was detected by 1H NMR,13C NMR,and MS,and the enatiomeric excess was determined by chiral HPLC analysis using a chiracel AD-H column.

关键词： chiral synthesis enantioselectivity enatiomeric excess chiral HPLC analysis

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Improvement of the electrochemical performance of LiNi_(0.33)Mn_(0.33)Co_(0.33)O_2.cathode material by chromium doping

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Science china(Technological Sciences) 2010年第12期53卷 3214-3220页

作者： WANG Meng1, CHEN YunBo1, WU Feng2. SU YueFeng2.& CHEN Lin1 1 Advanced Manufacture technology Center, china Academy of Machinery Sicence and technology, Beijing 100083, china 2.school of chemical engineering and environment, Beijing institute of technology, Beijing 100081, china 1. Advanced Manufacture technology Center China Academy of Machinery Sicence and Technology Beijing 100083 China2. School of Chemical Engineering and Environment Beijing Institute of Technology Beijing 100081 China

LiNi0.33Mn0.33-xCo0.33CrxO2.(x=0, 0.01, 0.02., 0.05) materials were synthesized by Cr3+ substitute of Mn4+ to enhance their electrochemical properties. The structure and electrochemical properties were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and charge/dis charge tests. The materials maintained the α-NaFeO2.type layered structure and the discharge capacities were also increase by doping appropriate amount of Cr3+. The sample with x= 0.02. exhibited the highest discharge capability of 181.6 mAh g?1 and the best cycle performance. EIS measurement showed that the Cr-doped electrode had the lower resistance impedance increase during cycling. The chemical diffusion coefficient of Li+ ion (DLi) was measured by potentiostatic intermittent titration technique (PITT). The result showed that DLi in Cr-doped electrode was faster than that of the un-doped one.

关键词： cathode material Cr-doped Li-ion battery electrochemical properties

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Adsorption of surfactants onto acrylic ester resins with different pore size distribution

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Science china Chemistry 2006年第5期49卷 445-453页

作者： YANG Weiben1,2.3,LI Aimin1,3,CAI Jianguo1,3,MENG Guanhua1,3 & ZHANG Quanxing1,3 1. State Key Laboratory of Pollution Control and Resource Reuse,school of the environment,Nanjing University,Nanjing 2.0093,{2. 2. Nanjing College of chemical technology,Nanjing 2.0048,{2. 3. Jiangsu engineering & technology Research Center for Organic Toxicant Control and Resource Reuse,Nanjing 2.0038,{2. 1. State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University Nanjing 210093 China 2. Nanjing College of chemical technology Nanjing 210048 China 3. Jiangsu engineering & technology Research Center for Organic Toxicant Control and Resource Reuse Nanjing 210038 China

In this study, a series of acrylic ester resins with different pore size distribution were prepared successfully by varying the type and the amount of pore-forming agents. In order to inves-tigate the adsorption behavior and mechanism of surfactants on acrylic ester resins, three kinds of surfactants were utilized as adsorbates that were sodium 6-dodecyl benzenesulfonate (6-NaDBS), sodium 1-dodecyl benzene sulfonate (1-NaDBS) and sodium 1-dodecyl sulfonate, respectively. It was observed that the surface area was available in a particular pore size and an appropriate pore size of resins appeared to be more important for the adsorption of surfactants. As compared to commercial acrylic ester resins XAD-7 and HP2.G, 50# and 38# resins exhibited more excellent adsorption properties toward 1-NaDBS and 6-NaDBS. The experimental equilibrium data were fitted to the Langmuir, and double-Langmuir models. Two models provided very good fittings for all resins over the temperature range studied. The investigation indicated that electrostatic attraction and hydrogen bond between resins and surfactants were the main forces and had an obvious effect on adsorption proc-ess.

关键词： acrylic ester resin, surfactant, adsorption, pore size distribution, isotherm.

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Theoretical studies on the possible conformers and properties of tetranitrodiazidoacetylhexaazaisowurtzitane (TNDAIW)

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Science china Chemistry 2004年第5期47卷 414-419页

作者： WU Yukai1, OU Yuxiang1, LIU Zhiguo1,2., LIU Jinquan1, MENG Zheng1 & CHEN Boren1 1. school of Materials Science and engineering, Beijing {2. of technology, Beijing 100081, china 2. school of Chemistry and chemical engineering, Henan University, Kaifeng 475001, china 1. school of Materials Science and engineering Beijing Institute of Technology 100081 Beijing China 2. school of Chemistry and chemical {2. Henan University 475001 Kaifeng China

Tetranitrodiazidoacetylhexaazaisowurtzitane (TNDAIW) is a novel polyazapolycyclic caged polyazidonitramine explosive first synthesized in our laboratory. All of the possible con- formers of TNDAIW are optimized using both the AM1 and PM3 methods. TNDAIW is predicted to have more polymorphs than hexanitrohexaazoisowurtzitane (CL-2.). The HF/6-31G(d) level of theory is used to investigate the lowest energy structures of D-TNDAIW for both AM1 and PM3. The possible conformers of TNDAIW are predicted to be more stable than epsilon-CL-2. based on the N-NO2.bond lengths. The impact and shock sensitivities of both the possible DA- and DP-TNDAIW are lower than the corresponding ones of epsilon-CL-2.. TNDAIW with the possible conformers is estimated to be a promising novel high energy density explosive.

关键词： tetranitrodiazidoacetylhexaazaisowurtzitane, molecular modeling, impact and shock sensitivities.

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Science china Chemistry 2004年第6期47卷 466-479页

作者： SONG Huajie1,2. XIAO Heming1 & DONG Haishan2.1. Department of Chemistry, Nanjing University of Science and technology, Nanjing 2.0094, china 2. {2. of chemical Materials, china Academy of engineering Physics, Mianyang 62.900, china 1. Department of Chemistry Nanjing University of Science and Technology 210094 Nanjing China 2. institute of chemical Materials China Academy of Engineering Physics 621900 Mianyang China

The symmetry-adapted perturbation theory (SAPT) that has the ability in decompo- sition of the total interaction energy into physically meaningful components is used to provide a more fundamental understanding of intermolecular forces. This work was motivated by the diffi- culty of standard SAPT in computing the intermolecular interactions for large energetic dimer systems. SAPT based on Kohn-Sham orbitals (SAPT(DFT)) proves computationally efficient for these large systems, but has been shown to perform poorly for interaction energy components. The deficiencies of SAPT(DFT) result from wrong asymptotical behaviors of commonly used exchange-correlation potentials. To remove the deficiencies, two asymptotic corrections by means of van Leeuwen and Baerends (LB) model potential and Fermi-Amaldi (FA) type potential were applied into three small test systems comprising He2. HF2.and (N2.2.and a set of larger ni- tramide dimers at several separations. The results showed that when utilizing newly developed frequency-dependent density susceptibilities (FDDS) technique for computing dispersion energy, the FA asymptotic correction is very effective to circumvent these deficiencies in SAPT(DFT) and yields a good accuracy over the LB correction. The FA corrected SAPT(DFT) approach is capa- ble of correctly predicting all the quantitative trends in binding energies for all test cases and substantially reduces computational cost as compared with the standard SAPT calculations. The successful application of the approach to nitramide dimer demonstrates that it potentially pro- vides a good means to calculate accurately intermolecular forces in larger system such as en- ergetic systems.

关键词： intermolecular interaction, density functional theory (DFT), symmetry adapted perturbation theory (SAPT), asymptotic correction, frequency-dependent density susceptibilities (FDDS).

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Early Hydration of Composite Cement with Thermal Activated Coal Gangue

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Journal of Wuhan University of technology(Materials Science) 2010年第1期25卷 162-166页

作者：郭伟 Department of Material engineering Yancheng Institute of Technology institute of Material Science and engineering Nanjing University of Technology

Composite cement samples were prepared by mixing clinker, gypsum with burnt coal gangues which was calcined at various temperatures. The mechanical strength and Ca（OH）2.content in the cement paste were tested, and the paste composition and microstructure were analyzed by thermogravimetry-differential thermal analysis （TG-DSC）, X-ray diffraction（XRD）, scanning electronic microscopy （SEM） and pore structure analysis. Results demonstrate that the thermal activated coal gangue could accelerate the early hydration of cement clinker obviously, which promotes the gangue hydration itself. The early hydrated products of the cement are C-S-H gel, Ca（OH）2.and AFt. The cement with 30% （in mass） the gangue exhibits higher mechanical strength, and among all the cement samples the one with the gangue burnt at 700 ℃ displays the highest hydration rate, mechanical strength, the most gel pores and the lowest total porosity.

关键词： blended cement hydration microstructure hydration product

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Effects of Cu^(2.) on characteristic of SV currents

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Science china Chemistry 2006年第6期49卷 560-564页

作者： ZHANG Liping1,2.& YANG Pin1 1. Key Laboratory of chemical Biology and Molecular engineering of Ministry of Education, {2. of Molecular Science, Shanxi University, Taiyuan 030006, china 2. {2. of environment Science, Taiyuan University of Science and technology, Taiyuan 03002., china 1. Key Laboratory of chemical Biology and Molecular engineering of Ministry of Education Institute of Molecular Science Shanxi University Taiyuan 030006 China 2. institute of environment Science Taiyuan University of Science and Technology Taiyuan 030024 China

Applying the patch-clamp technique to vacuoles from Radish we studied the effects of Cu2. on Slow Vacuolar (SV) current’s characteristic. Our results show that Cu2. in bath solution at higher concentration inhibits SV currents and the percentage of inhibition increases with increasing concentration and changes with different voltage. When at lower concentration, Cu2. significantly promotes the SV currents and the promotion ratio decrease with increasing voltage. At the same time, the time constants of activation become lesser after adding Cu2.. These results show that there may be some Cu2. binding sites on SV channels and binding to which can change SV current’s characteristic.

关键词： the patch-clamp technique, vacuolar, Cu2., SV channel.

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Structure and Pozzolanic Activity of Calcined Coal Gangue during the Process of Mechanical Activation

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Journal of Wuhan University of technology(Materials Science) 2009年第2期24卷 326-329页

作者：郭伟 Department of Material engineering Yancheng Institute of Technology institute of Material Science and engineering Nanjing University of Technology

On the basis of analyzing coal gangue＇s chemical and mineral compositions, the structure change of coal gangue during the mechanical activation was investigated by XRD, FTIR, NMR, and the mechanical strength of the cement doped coal gangue with various specific surface area was tested. The experimental results indicate that, the lattice structure of metakaolin in coal gangue samples calcined at 700 ℃ disorganizes gradually and becomes disordered, and the lattice structure of α-quartz is distorted slightly. The pozzolanic activity of the coal gangue increases obviously with its structural disorganization.

关键词： coal gangue mechanical activation structure NMR tetrahedron

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Degradation of anthracene, pyrene and benzo[a]-anthracene in aqueous solution by chlorine dioxide

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Science china Chemistry 2006年第6期49卷 565-572页

作者： LIU Jinquan1, HUANG Junli1, SU Liqiang2. CAO Xiangyu1 & JI Ying1 1. school of Municipal and environmental {2., Harbin institute of technology, Harbin 150090, china 2. school of Chemistry and chemical {2., Qiqihar University, Qiqihar 161006, china 1. school of Municipal and environmental {2. Harbin Institute of Technology Harbin 150090 China 2. school of Chemistry and chemical {2. Qiqihar University Qiqihar 161006 China

Polycyclic aromatic hydrocarbons (PAHs) constitute an important group of micropollutants, which are known to be mutagenic, carcinogenic and/or co-carcinogenic and relatively persistent in the environment. The effects of chlorine dioxide (ClO2. on the degradation of anthracene (ANTH), pyrene (PYR) and benzo[a]anthracene (BaA) in aqueous solution were investigated using high performance liquid chromatography (HPLC). In preliminary experiments, it was observed that ClO2.could remove these three PAHs effectively within a short time. Several factors including reaction time, the concentration of ClO2.and pH of the reaction mixture influencing the degradation ratio of PAHs have been studied by batch experiments. The results showed that the degradation ratio of PAHs was affected by reaction time and the concentration of ClO2.instead of pH. The degradation ratio of ANTH, PYR and BaA could reach their maximum as approximately 99.0%, 67.5% and 89.5%, respectively, under the condition as follows: reaction time 30, 60 and 12. min, the concentration of ClO2.0.1, 0.4 and 0.5 mmol·L-1, and pH 7.2. ANTH was selected as the representative to study the reaction mechanism with ClO2. The oxidation products formed in the reaction of ANTH with ClO2.were tentatively identified by gas chromatography-mass spectrometry (GC-MS), and the results showed that the main product was 9, 10-anthraquinone, which could be biodegraded more easily and quickly than ANTH. Through analyzing the reaction properties of ANTH and ClO2. the possible pathway for the ANTH-ClO2.reaction was proposed based on the theory of single electron transfer (SET).

关键词： chlorine dioxide, anthracene, pyrene, benzo[a]anthracene, degradation, reaction mechanism.

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