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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 Engineering and technology, {2. university of Mining and technology, Xuzhou 2.1008, {2. 2. State Key Laboratory of Solid Lubrication, Lanzhou Institute of chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, {2. 1. School of chemical Engineering 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.

Preparation of Sn-doped In_2._3 nanopowders by a solvothermal process

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Rare Metals 2008年第1期27卷 27-31页

作者： GU Yingying QIN Liping School of Chemistry and chemical Engineering Central South University Changsha 410083 China Science and technology Department Guangxi University ofTectmology Liuzhou 545006 China

Sn-doped In2.3（ITO） nanopowders in square shape were prepared in ethylene solvent by a solvothermal process,using In（4N） and SnCl4·5H2. as starting *** effects of solvothermal temperature and coprecipitation pH on the products were investigated using XRD,XPS,and *** of InOOH crystals and In4Sn3O12.crystals were prepared at 2.0°C or 2.0°C and ITO nanopowders with cubic structure were obtained at 2.0°C or above 2.0°*** the coprecipitation pH was 6,the product was ITO with impurity *** the pH was 9,the product was single phase ITO.

关键词： composite material ITO solvothermal process square shape

Eliminate indeterminacies of independent component analysis for chemometrics

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Progress in Natural Science:Materials International 2008年第8期18卷 1009-1014页

作者： Zhixiang Yao a,b, Kai Zhang c,*, Huanbin Liu b, Hui Su a a Department of biological and {2. Engineering, guangxi university of technology, liuzhou 545006, china b State Key Laboratory of Pulp and Paper-making Engineering, South china university of technology, Guangzhou 510640, china c State Key Laboratory of Heavy Oil Processing, china university of Petroleum, Beijing 102.49, china Department of biological and {2. Engineering Guangxi University of Technology Liuzhou 545006 China State Key Laboratory of Pulp and Paper-making Engineering South China University of Technology Guangzhou 510640 China State Key Laboratory of Heavy Oil Processing China University of Petroleum Beijing 102249 China

An improved method has been proposed to eliminate the indeterminacies of independent component analysis (ICA) for chemometrics. Following the arrangement of principal components analysis (PCA), the ICA mixing matrix is selected as signal content indexes, and ICA output are sorted and directed. After many times reputations, independent components (ICs) are paired according to the maximum correlation coefficient, and then the mean values of each IC substitutes the original ICs. This indicates that the ICA indeterminacies are eliminated. A simulation example is tested to validate this improvement. Finally, a set of experimental LC-MS data is processed without any prior knowledge or specific limitation and the results show that the improved ICA can directly separate the mixed signals in chemometrics, and it is simpler and more reasonable than the simple to use interactive self-modeling mixture analysis (SIMPLISMA).

关键词： Independent component analysis Indeterminacy in ICA Chemometrics

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, {2. of Science and technology of china, Hefei 2.002., china 2. Department of Physics, Yantai Teachers {2., Yantai 2.402., china 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).

A Series Piezoelectric Quartz Crystal Response Kinetics for *** Growth in the Presence of Cu(Ⅱ)

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Journal of Central South university 2000年第1期12卷 15-19页

作者： CHAI Li yuan 1,2.,WEI Wan zhi 2.YAO Shou zhuo 2.1. Department of Metallurgical Science and Engineering, Central South university of {2., Changsha 410083, china 2. College of Chemistry and chemical Engineering, Hunan university, Changsha 1. Department of Metallurgical Science and Engineering Central South University of Technology 410083 Changsha China 2. College of Chemistry and chemical Engineering Hunan University 410082 Changsha China

The kinetics on the growth of *** in the presence of Cu(Ⅱ) was studied using of series piezoelectric quartz crystal (SPQC). Arsenic ion inhibits the growth of *** , which is consistent with the previous results by other measuring methods. This further demonstrates that the SPQC can monitor the chemical activity of *** growth. Cupric ion accelerates the growth of *** . The mechanism was discussed, i. e., copper promotes the protein enzyme of *** , rusticyanin, to form over the range of cupric ion concentration studied. The reaction order of cupric ion in accelerating the bacterial growth is 0.067. The growth of *** is dependent on temperature, the apparent reaction activation energy decreases from 2..56 kJ/mol to 18.32.kJ/mol because of the addition of 10 mg/L Cu(Ⅱ) to the bacterial growth solution of pH 2.0 at initial inoculum of 10%.

关键词： series piezoelectric quartz crystal T.ferrooxidans growth kinetics sigmoid curve cupric ion

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.

Bipolar charged aerosol agglomeration and collection by a two-zone agglomerator

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Journal of Environmental Sciences 2001年第3期13卷 276-279页

作者： XIANG Xiao dong 1, CHEN Bao zhi 1, COLBECK I 2.(1. School of Resource and Civil Engineering, Northeastern university, Shenyang 110006, china. 2. Institute for Environmental Research, D{2. of biological and chemical Sciences, university of Es School of Resource and Civil Engineering Northeastern University Shenyang 110006 China.

In older to collect fine particles more efficiently, a new-type electrostatic agglomerator with two zones was developed. The distinguishing feature of this electrostatic agglomerator is that the particles are bipolarly charged and coagulated in the same alternating electric field simultaneously. The silica flour with 2.fun mass median diameter and the smoke from burning wood powder were used as test aerosol. The comparison experimental results have shown that when the mean electric field is 4 kV/cm the collection efficiency of the new electrostatic agglomerator was 98.2. for silica flour and 67.4% for wood powder smoke, Under the same experimental condition. the collection efficiency of the electrostatic agglomerator with three zones was 97.4% for collecting silica flour and the collection efficiency of the electrostatic precipitator was 56.3% for wood powder smoke.

关键词： charged particle agglomeration alternating electric field electrostatic agglomerator (EA) electrostatic precipitator (ESP) collection efficiency

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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 {2., Nanjing 2.0094, china 2. Institute 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).

Resonance scattering spectral detection of ultratrace IgG using immunonanogold-HAuCl_4-NH_2.H catalytic reaction

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Science china Chemistry 2008年第5期51卷 440-446页

作者： JIANG ZhiLiang1,2.ZHANG ShengSen1,LIANG AiHui2.& HUANG SiYu1 1 School of Environment and Resource,guangxi Normal university,Guilin 541001,{2. 2.Department of Material and chemical Engineering,Guilin university of technology,Guilin 541001,{2. 1. School of Environment and Resource Guangxi Normal University Guilin 541001 China 2. Department of Material and chemical Engineering Guilin University of Technology Guilin 541001 China

Nanogold particles of 10 nm were used to label goat anti-human IgG (GIgG) to obtain nanogold-labeled GIgG (AuGIgG). In a citrate-HCl buffer solution of pH 2.2.,AuGIgG showed a strong catalytic effect on the reaction between HAuCl4 and NH2.H to form big gold particles that exhibited a resonance scatter-ing (RS) peak at 796 nm. Under the chosen conditions,AuGIgG combined with IgG to form immuno-complex AuGIgG-IgG that can be removed by centrifuging at 16000 r/min. AuGIgG in the centrifuging solution also showed catalytic effect on the reaction. On those grounds,an immunonanogold catalytic RS assay for IgG was designed. With addition of IgG,the amount of AuGIgG in the centrifuging solution decreased; the RS intensity at 796 nm (I796 nm) decreased linearly. The decreased intensity ΔI796 nm was linear with respect to the IgG concentration in the range of 0.08-16.0 ng·mL-1 with a detection limit of 0.02.ng·mL-1. This assay was applied to analysis of IgG in sera with satisfactory sensitivity,selectivity and rapidity.

关键词： immunonanogold nanocatalysis gold-enhancement resonance scattering assay IgG