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Thermal-oxidation mechanism of dioctyl adipate base oil

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Friction 2016年第1期4卷 29-38页

作者： Xuzheng QIAN Yaling XIANG Hongfei shang Bingxue cheng Shengpeng ZHAN Jian LI State Key Laboratory of Special Surface Protection Materials and Application Technology Wuhan Research Institute of Materials Protection Wuhan 430030 China State Key Laboratory of Tribology Tsinghua University Beijing 100084 China

The ester base oil of dioctyl adipate (DOA) was oxidized in an oven at 200 degrees C for 30 h, and variations in the physicochemical and tribological properties were studied. To investigate the thermal-oxidation mechanism, the thermal-oxidation products were analyzed by gas chromatography-mass spectrometry (GC-MS), and the thermal-oxidation process was simulated using visual reactive force field molecular dynamics (ReaxFF MD). The results indicated that the total acid number (TAN) increased significantly because of the presence of 14% carboxylic acids and low molecular weight monoesters. The tribological properties were improved by the formation of the strongly polar carboxylic acids. Additionally, the increase in kinematic viscosity was limited due to the formation of high molecular weight polymerization products and low molecular weight degradation products. Thermal-oxidative degradation and polymerization mechanisms were proposed by combining ReaxFF MD simulations and GC-MS results.

关键词： dioctyl adipate GC-MS physicochemical properties tribological properties ReaxFF MD

Thickness-dependent phase transition and optical behavior of MoS2 films under high pressure

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Nano Research 2018年第2期11卷 855-863页

作者： Xuerui cheng Yuanyuan Li Jimin shang Chuansheng Hu Yufen Ren Miao Liu Zeming Qi School of Physics and Electronic Engineering Zhengzhou University of Light Industry Zhengzhou China National Synchrotron Radiation Laboratory University of Science and Technology of China Hefei China Energy Technologies Area Lawrence Berkeley National Laboratory Berkeley USA

We report the Raman and photoluminescence spectroscopic analysis of layered MoS2 under hydrostatic pressure up to 30 GPa. Unlike previous studies, throughout this work, a special treatment is applied to submerge monolayer, bilayer, multilayer （-200 layers）, and bulk MoS2 samples directly into silicone oil without a supporting substrate in a diamond anvil cell, thereby eliminating possible interference from substrate-film contact. A thickness-dependent trend is observed for the 2Hc-to-2Ha phase transition： The transition pressure increases from 19.0 to 25.6 GPa as the system thickness is reduced from bulk to multilayer MoS2; a further decrease in thickness to the bilayer structure increases the transition pressure to - 36 GPa, as predicted theoretically. This exceeds our measured pressure range, indicating the weakening of interlayer repulsive interactions as the MoS2 film thickness is reduced. Our experiment also reveals a monotonic trend of Raman peak shifting vs. film thickness under applied pressure, suggesting that the Raman vibration modes are more responsive to external pressure in thinner films. The photoluminescence emission peak of the monolayer MoS2 exhibits a blue shift under applied pressure at the rate of 23.8 ***-1. These results show that the structural and optical properties of MoS2 can be effectively modified by applying hydrostatic pressure.

关键词： molybdenum disulfide high pressure Raman spectroscopy photoluminescence diamond anvil cell

Life Prediction of Newly Developed Ferritic Stainless Steels for Automotive Muffler

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Journal of Iron and Steel Research International 2014年第1期21卷 125-130页

作者： Chao CHEN Yue ZHENG Yue ZHANG Xiao-hui LU cheng-jia shang Nuclear Equipment Division CNNC China Nuclear Power Engineering Co.Ltd. School of Materials Science and Engineering University of Science and Technology Beijing Nuclear and Radiation Safety Center MEP

Corrosion mechanism of automotive mufflers was investigated by SEM （scanning electron microscope） and XRD （X-ray diffractomer） analysis. 409L and newly developed 439M steels were evaluated in terms of condensate corrosion tests for 5 periods, 10 periods and 20 periods separately. The relative lifetimes of 409L and 439M steels were predicted according to the extreme value analysis method and pitting corrosion models. Modelling studies dem- onstrated that the predicted relative lifetime of 439M ferrite stainless steel is 6.8 times that of 409L steels. The extreme value analysis method was also successfully used in the road test. The estimated maximum corrosion depth of the 439M muffler is 0. 55 ram.

关键词： stainless steel SEMi XRD modelling study pitting corrosion

Achalasia combined with esophageal intramural hematoma:Case report and literature review

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World Journal of Gastroenterology 2010年第42期16卷 5391-5394页

作者： Yin-Yi Chu Kai-Feng Sung Soh-ching Ng Hao-Tsai cheng cheng-Tang Chiu Division of Gastroenterology Department of Internal MedicineShin Kong Wu Ho-Su Memorial HospitalTaipei 111TaiwanChina Department of Gastroenterology and Hepatology Chang Gung Memorial HospitalChang Gung University College of MedicineKweishanTaoyuan 333TaiwanChina Department of Gastroenterology and Hepatology Chang Gung Memorial HospitalChang Gung University College of Medicine KweishanTaoyuan 333TaiwanChina Department of Internal Medicine Chang Gung Memorial HospitalChang Gung University College of MedicineKeelung 204TaiwanChina

A 62-year-old male patient was admitted to our hospital due to severe chest pain,odynophagia,and *** computed tomography showed an esophageal submucosal ***(EGD) revealed a longitudinal purplish bulging tumor of the *** ultrasound(EUS) showed a mixed echoic tumor with partial liquefaction from the submucosal *** patient was diagnosed with esophageal intramural hematoma as well as achalasia by upper gastrointestinal endoscopy,esophagography and esophageal *** patient was managed conservatively with intravenous nutrition,and oral feeding was ***-up EGD and EUS showed complete recovery of the esophageal wall,and finally,the patient underwent endoscopic dilatation for *** patient was symptom free at the time when we wrote this manuscript.

关键词： Esophageal intramural hematoma Achalasia Endoscopic ultrasound

960 MPa Grade High Performance Weldable Structural Steel Plate Processed by Using TMCP

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Journal of Iron and Steel Research International 2010年第2期17卷 63-66页

作者： NIE Yi shang cheng-jia YOU Yang LI Xiu-cheng CAO Jian-ping HE Xin-lai School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

To develop high strength, good toughness, and weldable steel plate, a steel composition was designed. It was an ultra-low-carbon microalloyed steel. TMCP （thermal mechanical control process） and RPC （relaxation precipitation control） were employed to ensure fine lath bainite microstructure. This kind of microstructure could induce higher strength and better toughness.

关键词： low-carbon bainitic steel acicular ferrite substructure relaxation precipitation control

ON THE FEASIBILITY OF DETERMINING ELECTRON-NEUTRINO MASS FROM THE STUDY OF ELECTRON CAPTURE RATES IN ^(157)Tb

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Chinese Physics Letters 1984年第2期1卷 81-84页

作者： ching cheng-rui HO Tso-hsiu LIU Jia-lin Institute of Theoretical Physics Academia SinicaP.O.Box 2735BeijingChina

A comparison between the electron captures of 158Tb and 157Tb is presented. The practical merit of using 157Tb electron capture rates as a tool for electron-neutrino mass determination is analysed and emphasized.

关键词： RATE determination

LSM-YSZ nano-composite cathode with YSZ interlayer for solid oxide fuel cells

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Journal of Energy Chemistry 2017年第3期26卷 510-514页

作者： Zhongbo Liu Zhe Zhao Lei shang Dingrong Ou Daan Cui Baofeng Tu Mojie cheng Division of Fuel Cells Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences

Low temperature prepared(La;Sr;);MnO;-δ-Y;Zr;O;（LSM-YSZ） nano-composite cathode has high three-phase boundary（TPB） density and shows higher oxygen reduction reaction（ORR） activity than traditional LSM-YSZ cathode at reduced temperatures. But the weak connection between cathode and electrolyte due to low sintering temperature restrains the performance of LSM-YSZ nano-composite cathode. A YSZ interlayer, consisted of nanoparticles smaller than 10 nm, is introduced by spinning coating hydrolyzed YSZ sol solution on electrolyte and sintering at 800 °C. The thickness of the interlayer is about 150 nm. The YSZ interlayer intimately adheres to the electrolyte and shows obvious agglomeration with LSM-YSZ nano-composite cathode. The power densities of the cell with interlayer are 0.83, 0.46 and 0.21 W/cm;under 0.7 V at 800, 700 and 600 °C, respectively, which are 36%, 48% and 50% improved than that of original cell. The interlayer introduction slightly increases the ohmic resistance but significantly decreases the polarization resistance. The depressed high frequency arcs of impedance spectra suggest that the oxygen incorporation kinetics are enhanced at the boundary of YSZ interlayer and LSM-YSZ nanocomposite cathode, contributing to improved electrochemical performance of the cell with interlayer.

关键词： Solid oxide fuel cell LSM-YSZ cathode Interlayer Three-phase boundary Oxygen incorporation

Boosting the Energy Density of Flexible Asymmetric Supercapacitor with Three Dimensional Fe2O3 Composite Brush Anode

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Chemical Research in Chinese Universities 2020年第1期36卷 97-104页

作者： GAO Yuan ZHOU Ruitao WANG Dongrui HUANG Qiyao cheng ching-Hsiang ZHENG Zijian Laboratory for Advanced Interfacial Materials and Devices Institute of Textiles and ClothingThe Hong Kong Polytechnic UniversityHong Kong SARP.R.China Department of Industrial and Systems Engineering The Hong Kong Polytechnic UniversityHong Kong SARP.R.China

Flexible asymmetric supercapacitor is fabricated with three dimensional(3D)Fe2O3/Ni(OH)2 composite brush anode and Ni(OH)2/MoO2 honeycomb *** for 3D composite brush anode,a layer of thin Fe2O3 film is firmly adhered on a 3D Ni brush current collector with the assist of Ni(OH)2,functioning as both adherence layer and pseudocapacitive active *** unique 3D Ni brush current collector possesses large surface area and stretching architecture,which facilitate to achieve the composite anode with high gravimetric capacitance of 2158 F/*** terms of cathode,Ni(OH)2 and MoO2 have a synergistic effect to improve the specific capacitance,and the resulting Ni(OH)2/MoO2 honeycomb cathode shows a very high gravimetric capacitance up to 3264 F/*** asymmetric supercapacitor(ASC)has balanced cathode and anode,and exhibits an ultrahigh gravimetric capacitance of 1427 F/g and an energy density of 476 W·h/*** energy density of ASC is 3-4 times higher than those of other reported aqueous electrolyte-based supercapacitors and even comparable to that of commercial lithium ion *** device also shows marginal capacitance degradation after 1000 cycles'bending test,demonstrating its potency in the application of flexible energy storage devices.

关键词： Asymmetric supercapacitor High energy density Flexible device Three dimensional(3D) Fe2O3 compo-site anode

Intrinsic Features of an Ideal Glass

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Chinese Physics Letters 2017年第7期34卷 76-79页

作者： Deyan Sun cheng shang Zhipan Liu Xingao Gong Department of Physics East China Normal University Shanghai 200062 Department of Chemistry Fudan University Shanghai 200433 Key Laboratory for Computational Physical Sciences （MOE） State Key Laboratory of Surface Physics Department of Physics Fudan University Shanghai 200433 Collaborative Innovation Center of Advanced Microstructures Nanjing 210093

In order to understand the long-standing problem of the nature of glass states, we perform intensive simulations on the thermodynamic properties and potential energy surface of an ideal glass. It is found that the atoms of an ideal glass manifest cooperative diffusion, and show clearly different behavior from the liquid state. By determining the potential energy surface, we demonstrate that the glass state has a fiat potential landscape, which is the critical intrinsic feature of ideal glasses. When this potential region is accessible through any thermal or kinetic process, the glass state can be formed and a glass transition will occur, regardless of any special structural character. With this picture, the glass transition can be interpreted by the emergence of conlgurational entropies, as a consequence of flat potential landscapes.

关键词： GS AI

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