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Chinese Journal of Structural Chemistry 2016年第2期35卷 193-198页

作者： cheng xue-Li (School of Chemistry and Chemical Engineering Taishan UniversityTai'anShandong 271021China

The reaction mechanisms of Ti（~3F）＋ CH2C12→CH2=TiCl2 and Ti（~3F）＋ CHC13→HC÷TiCl3 were investigated with Gaussian 03 program package at the B3PW91/6-311＋＋G（d,p）*** computational results revealed that：1） Both reaction systems are initiated by Ti（~3F） atom attacking the C atom of CH2C12 and CHCl3 to activate a C-Cl bond;2） Both reaction systems were carried out via triplet reaction channels;3） CH2=TiCl2 has singlet and triplet isomers,and the singlet one is more stable;4） The HOMO of CH2=TiCl2（S） illustrates a π-bonding interaction between C and Ti;5） Only singlet HC÷TiCl3 was located,and the Mulliken atomic spin densities show that the two single electrons are mostly on the C atom.

关键词： B3PW91 reaction mechanism Ti(~3F) CH2=TiCl2 HOTiCl3

Synthesis of one-dimensional GaN nanorods by Tb intermediate layer with different thicknesses

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Rare Metals 2016年第12期35卷 937-939页

作者： jin-Hua Chen Ping Shi Yu-Lan Li xue-Lei Sun cheng-Shan xue Ji-Yuan Guo Department of Mechanical and Electrical Engineering Zhenjiang Vocational Technical College College of Physics and Electronics Shandong Normal University College of Mathematics and Physics Jiangsu University of Science and Technology

GaN nanorods were synthesized by magnetron sputtering and ammonification system, and the thickness of Tb intermediate layer was changed to study the effect on GaN nanorods. The resultant was tested by scanning electron microscopy （SEM）, X-ray diffraction （XRD）, transmission electron microscopy （TEM）, high-resolution transmission electron microscopy （HRTEM）, and photo- luminescence （PL） spectra. The results show that the thickness of Tb layer has an evident effect on the modality, quality, and luminescence properties of GaN nanorods. PL spectra at room temperature show a very strong emission peak at 368 nm and a weak emission peak at 387 nm, and the intensities of the peak for the produced samples reach the maximum when Tb layer is 20 nm. Finally, the optimal thickness of 20 nm of Tb intermediate layer for synthe- sizing GaN nanostructures is achieved.

关键词： GaN nanorods Tb intermediate layer Single crystal Photoluminescence

Lymphovascular invasion in rectal cancer following neoadjuvant radiotherapy: A retrospective cohort study

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World Journal of Gastroenterology 2009年第30期15卷 3793-3798页

作者： Chang-Zheng Du Wei-cheng xue Yong Cai Ming Li jin Gu Department of Colorectal Surgery Peking University School of Oncology Beijing 100142 China Department of Pathology Peking University School of Oncology Beijing 100142 China Department of Radiotherapy Peking University School ofOncology Beijing 100142 China

AIM: To investigate the meaning of lymphovascular invasion (LVI) in rectal cancer after neoadjuvant radiotherapy. METHODS: A total of 325 patients who underwent radical resection using total mesorectal excision (TME) from January 2000 to January 2005 in Beijing cancer hospital were included retrospectively, divided into a preoperative radiotherapy (PRT) group and a control group, according to whether or not they underwent preoperative radiation. Histological assessments of tumor specimens were made and the correlation of LVI and prognosis were evaluated by univariate and multivariate analysis. RESULTS: The occurrence of LVI in the PRT and control groups was 21.4% and 26.1% respectively. In the control group, LVI was signifi cantly associated with histological differentiation and pathologic TNM stage, whereas these associations were not observed in the PRT group. LVI was closely correlated to disease progression and 5-year overall survival (OS) in both groups. Among the patients with disease progression, LVI positive patients in the PRT group had a signifi cantly longer median disease-free period (22.5 mo vs 11.5 mo, P = 0.023) and overall survival time (42.5 mo vs 26.5 mo, P = 0.035) compared to those in the control group, despite the fact that no signifi cant difference in 5-year OS rate was observed (54.4% vs 48.3%, P = 0.137). Multivariate analysis showed the distance of tumor from the anal verge, pretreatment serum carcinoembryonic antigen level, pathologic TNM stage and LVI were the major factors affecting OS. CONCLUSION: Neoadjuvant radiotherapy does not reduce LVI significantly; however, the prognostic meaning of LVI has changed. Patients with LVI may benefi t from neoadjuvant radiotherapy.

关键词： Lymphovascular invasion Rectal cancer Neoadjuvant radiotherapy Total mesorectal excision Pathology Prognosis

Current-carrying friction in carbon coated ball bearing

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Friction 2023年第11期11卷 2008-2020页

作者： Peidong xue cheng CHEN xue FAN Dongfeng DIAO Institute of Nanosurface Science and Engineering(INSE) Guangdong Provincial Key Laboratory of Micro/Nano Optomechatronics EngineeringShenzhen UniversityShenzhen 518060China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China

In this work,we proposed a method for coating the whole surfaces of bearing balls uniformly by carbon film with a rotatable ball *** studied the carbon/carbon friction with a self-designed currentcarrying ball bearing friction test system.A notable and instant friction force drop of 28%and significant carbon film wear alleviation were found when currents were *** using TEM-,SEM-,and EDS-analysis,special carbon stacks with a mixture of large wear particles and oxide were found in the wear areas under current applied *** elucidated the current-carrying friction mechanisms as follows:(1)wear particles formation;(2)wear particles charged by tribomicroplasma;(3)formation of surface passivated carbon stacks under electric force;(4)sliding between passivated carbon *** work may facilitate the development of novel solid-lubricated ball bearings and lay some foundations for current-carrying rolling friction.

关键词： current-carrying friction carbon film ball bearing carbon stack

From aqueous Zn-ion battery to Zn-MnO_(2) flow battery:A brief story

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Journal of Energy Chemistry 2021年第3期30卷 194-201页

作者： Tong xue Hong jin Fan School of Materials Science and Engineering North Minzu UniversityYinchuan 750021NingxiaChina School of Physical and Mathematical Sciences and Innovative Centre for Flexible DevicesNanyang Technological UniversitySingapore 637371Singapore

Aqueous Zn-ion battery(AZIB)has become an attractive technology because of its unique features of low cost,high safety and the ***_(2) is the model cathode material for AZIB since the first report on reversible Zn-MnO_(2) battery,but recent studies have unveiled different charge storage *** to revamping of the electrochemistry and redesigning of the electrolyte and interface,there is tremendous performance enhancement in *** mini Review will first give a brief introduction of ZIB,including fundamentals of materials and components,and the progress in recent ***,a general classification of working mechanisms related to MnO_(2) in neutral and mildly acidic electrolyte is *** focus is put on the recent blossoming Zn-MnO_(2) electrolytic mechanism,which has given birth to the Zn-MnO_(2) redox flow batteries that are highly promising for large-scale static energy storage.

关键词： Aqueous zinc-ion battery Deposition/dissolution Electrolytic battery Zn-MnO2 flow battery

Strain Engineering for the Kapitza Resistance of the ZrO_(2)/α-Al_(2)O_(3)and YSZ/α-Al_(2)O_(3)Interfaces

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Acta Mechanica Solida Sinica 2022年第1期35卷 101-112页

作者： Yixuan xue jin-Wu Jiang Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China

The Kapitza resistance is of fundamental importance for the thermal stability of the interface between the ceramic top coat and the thermal growth oxide layer in the thermal barrier coating structure,which is widely used to protect high-temperature components in current gas turbine *** top coat typically consists of the ZrO_(2)partially stabilized by 8%Y2O3(YSZ),and the main component of the thermal growth oxide isα-Al_(2)O_(3).In this work,the Kapitza resistance is found to be a small value of 0.69 m^(2)K/GW for the YSZ/α-Al_(2)O_(3)interface based on the heat dissipation simulation *** indicates that the localization of thermal energy is rather weak,which is beneficial for the thermal stability of the YSZ/α-Al_(2)O_(3)*** Kapitza resistance can be further reduced to 0.50 m^(2)K/GW by a mechanical or thermal compressive strain of 8%.To explore the underlying mechanism for this strain effect,we analyze the phonon vibration and the microscopic deformation in the interface *** is revealed that the interface becomes denser through the compression-induced twisting of some Al-O_(zr)and A1-O_(Al)chemical bonds in the interface region,which is responsible for the reduction in the Kapitza *** temperature effect and crystal size effect on the Kapitza resistance of the YSZ/α-Al_(2)O_(3)interface are also systematically *** findings shall provide valuable information for further understanding of the thermal conductivity and thermal stability of the thermal barrier coating structures.

关键词： Kapitza resistance Compressive strain Temperature Size

Quantification of the Activation Capabilities of Lewis/Brφnsted Acid for Electrophilic Trifluoromethylthiolating Reagents

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Chinese Journal of Chemistry 2020年第2期38卷 130-134页

作者： Huiying Kang Biying Zhou Man Li Xiao-Song xue jin-Pei cheng State Key Laboratory of Elemento-Organic Chemistry Collaborative Innovation Center of Chemical Science and EngineeringNankai UniversityTianjin 300071China Center of Basic Molecular Science Department of ChemistryTsinghua UniversityBeijing 100084China

Summary of main observation and conclusion Electrophilic trifluoromethylthiolation has emerged as an important and efficient methodology for installing the SCF3 moiety onto an array of organic *** to the low reactivities of trifluoromethylthiolating reagents,these transformations often require activation through an exogenous Lewis/Br0nsted *** report herein the quantification of the activation capabilities of Lewis/Br0nsted acids for trifluoromethylthiolating reagents through computing the differenee in trifluoromethylthio cation donor ability(Tt+DA)between the"activated"and"unactivated"reagent.A moderate correlation is found to exist between the activation capability and Lewis acidity.

关键词： activation moiety donor

Expression of c-fos in Rat Brain as a Prelude Marker of Central Nervous System Injury in Response to Methylmercury-stimulation

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Biomedical and Environmental Sciences 2006年第1期19卷 67-72页

作者： jin-PING cheng WEN-HUA WANG jin-PING JIA MIN ZHENG WEI SHI xue-YU LIN School of Environmental Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China School of Public Heath Fudan University Shanghai 200032 China College of Environment and Resources Jilin University Changchun 130026 Jilin China

Objective To probe into the prelude marker of central nervous system injury in response to methyl mercury chloride （MMC） stimulation and the signal transduction molecular mechanism of injury in rat brain induced by MMC. Methods The expression of c-fos mRNA in brain and the expression of c-FOS protein in cortex, hippocampus and ependyma were observed using reverse transcription polymerase chain reaction （RT-PCR） and immunocytochemical methods. The control group was injected with physiological saline of 0.9%, while the concentrations for the exposure groups were 0.05 and 0.5, 5 mg/kg MMC respectively, and the sampling times points were 20, 60, 240, 1440 min. Results The expression of c-FOS protein in cortex and hippocampus increased significantly, the accumulation of mercury in the brain induced by 0.05 mg/Kg MMC for 20 min had no significant difference compared with the control group. The mean value was 0.0044 mg/Kg, while the protein c-FOS expression had significant difference compared with the control group （P〈0.01）. More sensitive expression occurred in hippocampus and cortex, but not in ependyma. Conclusion The expression of c-FOS protein in cortex and hippocampus can predict the neurotoxicity of MMC in the early time, and immediately early gene （lEG） c-fos participates in the process of brain injury induced by MMC.

关键词： Methyl mercury c-fos Central nervous system Early prediction

An integration method based on a novel combined flow for aerodynamic configuration of strutjet engine

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Chinese Journal of Aeronautics 2021年第9期34卷 156-167页

作者： Longsheng xue Chuan cheng chengpeng WANG Keming cheng College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Key Laboratory of Unsteady Aerodynamics and Flow Control Ministry of Industry and Information TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016China Aerospace System Engineering Shanghai Shanghai 201100China

In this paper a novel design method of aerodynamic configuration is proposed to integrate forebody,strut and inlet for strutjet engine,and a model at design point of Mach number6 is generated to investigate the aerodynamic performance by both simulations and *** basic flow field employed by proposed method is a combined flow named IBB,which is combined by Internal Conical Flow A(ICFA),truncated Busemann flow I(BI)for external section,and truncated Busemann flow II(BII)for internal *** model configuration is generated by streamline tracing method from basic flow field,in which the forebody section is traced from ICFA and BI flows,and the inlet as well as strut section is traced from BII *** simulations in Mach number 4,5,and 6 demonstrate uniform starting flow fields with relatively high total pressure recovery,which agree well with experiments in wind ***,in low Mach number cases,this inlet could start at Mach number 3 while it is unstarted at Mach number 2.7;in high Mach number cases,a uniform flow could still exist in Mach number 6.5 while a relatively strong shock wave boundary layer interaction is found in cowl area of Mach number 7 case,indicating the inlet designed by proposed method works in a relatively wide Mach number range.

关键词： Airframe-propulsion integration Busemann flow Combined flow Hypersonics Wind tunnel test

Absorption and Emission Spectra of p-Phenylbenzoyl Methanthiol: Methanol Effect Based on M06-2X Calculations

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Chinese Journal of Structural Chemistry 2019年第3期38卷 476-482页

作者： cheng xue-Li School of Chemistry and Chemical Engineering Taishan University

The absorption and emission spectra, as well as the photolysis mechanism of p-phenylbenzoyl methanthiol in methanol and in gas phase were elucidated in detail based on the molecular structures of the ground states, excited states and their spectroscopic characters. The TD-M062 X calculations demonstrate that the S_1 state in gas phase will decompose into SH and p-phenylbenzoyl radical via a barrierless process, but the T_1 and T_2 do not photolyze. By adding 1 and 2 methanol molecules onto p-phenylbenzoyl methanthiol, the CPCM model can perfectly describe the solvation effects of methanol. Methanol may stabilize the excitation states, but also protects the resulting radical products from recombination.

关键词： TD-M062X photodecomposition CIS absorption spectra