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Chinese Journal of Chemical Physics 2008年第1期21卷 45-54页

作者： Jing-bo Wang Jian-yi Ma xiang-yuan li Fu-cheng He Ke-xiang Fu College of Chemical Engineering Sichuan University Chengdu 610065 China Institute for Nanobiomedical Technology and Membrane Biology 5ichuan University Chengdu510055 China

A novel algorithm was designed and implemented to realize the numerical calculation of the solvent reorganization energy for electron transfer reactions, on the basis of nonequilibrium solvation theory and the dielectric polarizable continuum model. Applying the procedure to the well-investigated intramoleeular electron transfer in biphenyl-androstane-naphthyl and biphenyl-androstane-phenanthryl systems, the numerical results of solvent reorganization energy were determined to be around 60 k J/mol, in good agreement with experimental data. Koopman＇s theorem was adopted for the calculation of the electron transfer coupling element, associated with the linear reaction coordinate approximation. The values for this quantity obtained are acceptable when compared with experimental results.

关键词： Nonequilibrium salvation Electron transfer Solvent reorganization energy Continuum model

Shock tube study of n-decane ignition at low pressures

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Acta Mechanica Sinica 2012年第1期28卷 79-82页

作者： Xiao-Fei Nie Ping li Chang-Hua Zhang Wei Xie Cong-Shan li xiang-yuan li Institute of Atomic and Molecular Physics Sichuan University610065 ChengduChina Sichuan University 610065 ChengduChina

Ignition delay times for n-decane/O2/Ar mixtures were measured behind reflected shock waves using endwall pressure and CH＊ emission measurements in a heated shock tube. The initial postshock conditions cover pressures of 0.09-0.26 MPa, temperatures of 1 227-1 536 K, and oxygen mole fractions of 3.9%-20.7% with an equivalence ratio of 1.0. The correlation formula of ignition delay dependence on pressure, temperature, and oxygen mole fraction was obtained. The current data are in good agreement with available low-pressure experimental data, and they are then compared with the prediction of a kinetic mechanism. The current measurements extend the kinetic modeling targets for the n-decane combustion at low pressures.

关键词： Ignition delay time n-Decane Heated shock tube

Laser absorption spectroscopy for high temperature H_2O time-history measurement at 2.55 μm during oxidation of hydrogen

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Chinese Physics B 2018年第7期27卷 376-381页

作者： Yu-Dan Gou De-xiang Zhang Yi-Jun Wang Chang-Hua Zhang Ping li xiang-yuan li Institute of Atomic and Molecular Physics Sichuan UniversityChengdu 610065China College of Chemical Engineering Sichuan UniversityChengdu 610065China

Concentration time-histories of H20 were measured behind reflected shock waves during hydrogen combustion. Experiments were conducted at temperatures of 1117-1282 K, the equivalence ratios of 0.5 and 0.25, and a pressure at 2 atm using a mixture of H2/O2 highly diluted with argon. H2O was monitored using tunable mid-infrared diode laser absorption at 2.55 μm （3920.09 cm-1）. These time-histories provide kinetic targets to test and refine reaction mechanisms for hydrogen. Comparisons were made with the predictions of four detailed kinetic mechanisms published in the last four years. Such comparisons of H2O concentration profiles indicate that the AramcoMech 2.0 mechanism yields the best agreement with the experimental data, while CRECK, San Diego, and HP-Mech mechanisms show significantly poor predictions. Reaction pathway analysis for hydrogen oxidation indicates that the reaction H ＋ OH ＋ M = H20 ＋ M is the key reaction for controlling the H2O formation by hydrogen oxidation. It is inferred that the discrepancy of the conversion percentage from H to H20 among these four mechanisms induces the difference of performance on H2O time-history predictions. This work demonstrates the potential of time-history measurement for validation of large reaction mechanisms.

关键词： tunable diode laser absorption spectroscopy H20 time-history profile combustion process reac- tion mechanism

Validation concurrency control protocol in parallel real-time database systems

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Journal of Central South University of Technology 2002年第3期9卷 197-201页

作者： LEI xiang-dong(雷向东) yuan Xiao-li(袁晓莉) College of Information Science and Engineering Central South University Changsha 410083 China College of Information Science and Engineering Central South University Changsha 410083 China

In parallel real-time database systems, concurrency control protocols must satisfy time constraints as well as the integrity constraints. The authors present a validation concurrency control(VCC) protocol, which can enhance the performance of real-time concurrency control mechanism by reducing the number of transactions that might miss their deadlines, and compare the performance of validation concurrency control protocol with that of HP2PL(High priority two phase locking) protocol and OCC-TI-WAIT-50(Optimistic concurrency control-time interval-wait-50) protocol under shared-disk architecture by simulation. The simulation results reveal that the protocol the author presented can effectively reduce the number of transactions restarting which might miss their deadlines and performs better than HP2PL and OCC-TI-WAIT-50. It works well when arrival rate of transaction is lesser than threshold. However, due to resource contention the percentage of missing deadline increases sharply when arrival rate is greater than the threshold.

关键词： parallel database system real-time database concurrency control validation transactions

MUC1-positive circulating tumor cells and MUC1 protein predict chemotherapeutic efficacy in the treatment of metastatic breast cancer

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Chinese Journal of Cancer 2011年第1期30卷 54-61页

作者： Jian-Ping Cheng Ying Yan xiang-Yi Wang yuan-li Lu Yan-Hua yuan Jun Jia Jun Ren Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education) Peking University School of Oncology Department of Medical Oncology Beijing Cancer Hospital & Institute Beijing 100142 P. R. China.

Chemotherapy plays an important role in the treatment of metastatic breast cancer. It is important to monitor chemotherapeutic efficacy, to find a simple and efficient tool to guide treatment, and to predict the efficacy of treatment in a timely and accurate manner. This study aimed to detect mucin-1 (MUC1) - positive circulating tumor cells and MUC1 protein in the peripheral blood of patients with metastatic breast cancer and to investigate their relationship to chemotherapeutic efficacy. MUC1 mRNA was detected in the peripheral blood of 34 patients with newly diagnosed metastatic breast cancer by reverse transcription- polymerase chain reaction. The positive rates of MUC1 mRNA were 88.2% before chemotherapy and 70.6% after chemotherapy, without a significant difference (P = 0.564); MUC1 mRNA expression before chemotherapy had no correlation with treatment effectiveness (P = 0.281). The response rate of MUC1 mRNA -negative patients after first-cycle chemotherapy was significantly higher (P = 0.009) and the progression-free survival (PFS) was clearly longer than those of MUC1 mRNA-positive patients (P = 0.095). MUC1 protein in peripheral blood plasma was detected by an EliSA competitive inhibition assay. The patients with decreased MUC1 protein after chemotherapy had a significantly longer PFS than those with elevated MUC1 protein (P = 0.044). These results indicate that the outcomes of MUC1 mRNA - negative patients after chemotherapy are better than those of MUC1 mRNA-positive patients. In addition, patients with decreased expression of MUC1 protein have a better PFS.

关键词： MUC1 治疗效果肿瘤细胞阳性率乳腺癌转移性粘蛋白化疗

Improved activity of Ni-Mo/SiO_(2) bimetallic catalyst synthesized via sol-gel method for methylcyclohexane cracking

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Petroleum Science 2021年第5期18卷 1530-1542页

作者： Jun Zhang Ting Chen Yi Jiao Mei Cheng lin-lin Wang Jian-li Wang xiang-yuan li Yao-Qiang Chen School of Chemical Engineering Sichuan UniversityChengdu610064SichuanChina Institute of New Energy and Low-Carbon Technology Sichuan UniversityChengdu610064SichuanChina College of Chemistry Sichuan UniversityChengdu610064SichuanChina

To improve the cracking behavior of hydrocarbon,Ni-Mo/SiO_(2) bimetallic catalysts were synthesized by different preparation methods(sol-gel,co-impregnation and single-impregnation) and added the additives(citric acid,polyethylene glycol and cetyltrimethylammonium bromide) based on the most suitable method *** cracking reaction of methylcyclohexane under supercritical conditions was performed as the probe reaction to estimate the catalytic performance,and the properties of Ni-Mo/SiO_(2) catalyst were characterized by N_(2) absorption-desorption,XRD,XPS,H_(2)-TPR,NH_(3)-TPD,in-situ IR of NH_(3) desorption,HRTEM and STEM-mapping so as to study the structure-activity *** catalyst synthesized via sol-gel method showed the best conversion and heat sink,being 81.8% and 3.81 MJ/kg,which was closely related to strong mutual effect between active components and SiO_(2) as well as strong acid ***,the introduction of additives by sol-gel method has an affirmative influence on properties of Ni-Mo/SiO_(2) catalysts,being that the acidity(more L and B acid sites) was modulated and organic groups interact with metal to suppress the aggregation of metal species(Ni and Mo),thereby enhancing the catalytic *** 750℃,the conversion(89.3%) as well as heat sink(3.99 MJ/kg) of MCH cracking obtained an optimum over Ni-Mo/SiO_(2) catalyst with addition of citric acid.

关键词： Ni dispersion Ni-Mo/SiO_(2) Catalytic cracking Citric acid Sol-gel method Acidity modulation

Continuum Model for Electronic Polarization Based on a Novel Dielectric Response Function

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Chinese Journal of Chemical Physics 2009年第5期22卷 481-488,I0001页

作者： Quan-deWang Han-yu Wu Ke-xiang Fu xiang-yuan li College of Chemical Engineering Sichuan University Chengdu 610065 China

A generalized response function based on the use of dielectric spectra for dielectric relaxation process is derived. We apply the general response function to the special case in order to examine how special dielectric relaxation functions developed by other authors for solvent relaxation can be derived based on our formulations. Three typical solvents, water, methanol, and acetonitrile are used to investigate the electronic polarization processes of polar solvents. The solvent electronic polarization process is shown after a linear variation with the external electric field imposed on the solvent. The results show a conclusion that the electronic polarization of the solvents will accompany the electronic transition synchronously, without time lag.

关键词： Response function Dielectric relaxation Electronic polarization Continuummodel

Photoinduced Electron Transfer on the Donor-Bridge-Acceptor System

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Photoinduced Electron Transfer on the Donor-Bridge-Acceptor ...

Spectral shifts for coumarin 153 based on a new expression of nonequilibrium solvation energy

中国化学会第十二届全国量子化学会议

作者： Juan-Qin li xiang-yuan li aCollege of Chemical Engineering Sichuan University

Quantum-chemical techniques are applied to model the mechanisms of photoinduced charge transfer from aπ-electron donating group(2,3-dimethoxynaphthalene,D)to aπ-electron-acceptor moiety(2,3-dicyanonaphthalene,A)separated by a bridge of increasing size(n-norbornadiene,n=1,B).The main parameters controlling the transfer rate have been calculated:the internal and external reorganization energy terms,the electronic coupling between the initial and final states,and the variation of the Gibbs *** charge transfer is shown to proceed in these compounds through two competing mechanisms,super exchage versus bridge-mediated *** excited states of a donor-bridge-acceptor(DBA)model system have been investigated using time-dependent density-functional theory(TD-DFT)in gas phase and in *** calculated results are consistent with the experimental observation[1,2].The spectroscopic properties of isolated donor,acceptor,and bridge and the bridge-donor compound have been investigated at the TD-B3LYP/6-31+G**** study showed that TD-DFT method gives a good description in the excited state energy calculation,and the calculated results are in acceptable agreement with experimental data[3].

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Spectral shifts for coumarin 153 based on a new expression o...

Spectral shifts for coumarin 153 based on a new expression of nonequilibrium solvation energy

中国化学会第30届学术年会-第十八分会：电子结构理论方法的发展与应用

作者： Ting-Jun Bi xiang-yuan li College of Chemical Engineering Sichuan University

The electrostatic free energy of nonequilibrium solvation in a continuous dielectric has always been a controversial *** propose a novel nonequilibrium solvation theory differ from traditional method of reversible wor...

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Spectral shifts for coumarin 153 based on a new expression o...