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Mechanical behavior study of microdevice and nanomaterials by Raman spectroscopy:a review

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Chinese Science Bulletin 2014年第23期59卷 2811-2824页

作者： Wei qiu yi-Lan Kang Tianjin Key Laboratory of Modern Engineering Mechanics Department of MechanicsTianjin University

With the rapid development of micro/nano manufacturing technology and nanomaterials,the accurate measurement of the mechanical properties and behaviors at the micro-nano scale represents a new field of mechanical *** spectroscopy,which is based on lattice dynamics theory,is applicable to the detection of the statistical information of the lattice structure deformation within the measuring *** to its peculiarities,such as non-destructiveness,convenience and high-resolution,this technology allows the on-line in situ measurement of residual stress in microstructures caused by processing and can also achieve the real-time deformation of graphene,carbon nanotubes and other nanomaterials under force *** recent years,mechanical measurements based on Raman spectroscopy technology have developed *** this review,Raman-based stress measurement theories for several commonly used materials are briefly *** related to the residual stress measurements of microstructure and experimental investigations of the mechanical properties of low-dimensional nanomaterials are then ***,the development trend of this method is proposed.

关键词：拉曼光谱仪动力学理论纳米材料行为研究纳米制造技术残余应力测量展望微型

Micromechanics-based analysis for predicting asphalt concrete modulus

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第6期11卷 415-424页

作者： Xing-yi ZHU Zhi-yi HUANG Zhong-xuan YANG Wei-qiu CHEN Department of Civil Engineering Zhejiang University Hangzhou 310058 China Department of Engineering Mechanics Zhejiang University Hangzhou 310027 China

The elastic modulus of asphalt concrete(AC) is an important material parameter for pavement *** prediction and determination of elastic modulus,however,largely depends on laboratory tests which cannot reflect explicitly the influence of the microstructure of *** this end,a micromechanical model based on stepping scheme is *** is given to the influence of interfacial debonding and interlocking effect between the aggregates and asphalt mastic using the concept of effective *** on asphalt mixture with various microstructures are conducted to verify the proposed *** is shown that the prediction is generally in agreement with experimental *** affecting the elastic modulus of AC are also discussed in light of the proposed method.

关键词： Asphalt concrete(AC) Micromechanics Microstructure Effective bonding Optimum design Elastic modulus

A method for neutron-induced gamma spectra decomposition analysis based on Geant4 simulation

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Nuclear Science and Techniques 2022年第12期33卷 36-48页

作者： Wei Tang Jin-gang Liang yi Ge Qiong Zhang University of Electronic Science and Technology of China Chengdu 610000China Tsinghua University Beijing 10000China

In various monitoring and detection tools that use pulsed neutron generators as radiation sources,the gamma rays induced by the interaction with various nuclei at different stages of neutron transport can reflect information about the *** gamma rays are generated in two major interactions:inelastic scattering of fast neutrons and radiative capture of thermal neutrons,corresponding to the inelastic and capture gamma rays,***,the two types of gamma rays that reflect different properties of the medium are difficult to collect by normal detectors *** proportion of the two gamma rays needs to be solved for the separation of inelastic and capture ***,this study proposes an optimized spectra decomposition method to calculate the inelastic-to-capture ratio in the measured total gamma spectra based on the net inelastic and capture spectra obtained using the Geant4 *** the simulated data cannot reflect the energy resolution of the measured spectra,we introduce the Gaussian broadening function of the gamma detector while calculating the proportion of the spectra components,and achieve optimization of the proportion values and resolution parameters *** on the results,the total simulated spectra obtained by superimposing the broadened net inelastic and capture gamma spectra according to the calculated inelastic-to-capture ratio are in good agreement with their measured counterpart.

关键词： Neutron-induced gamma Geant4 Spectra analysis

Preoperative diabetes as a protective factor for pancreatic fistula after pancreaticoduodenectomy: a meta-analysis

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Hepatobiliary & Pancreatic Diseases International 2015年第2期14卷 132-138页

作者： Xiang Xia Chen Huang gang Cen Zheng-Jun qiu Department of General Surgery Shanghai Jiaotong University Affiliated First People's Hospital

BACKGROUND： The role of diabetes mellitus （DM） in pancreatic fistula （PF） or clinical relevant PF （CR-PF） after pancreaticoduodenectomy （PD） or pylorus-preserving pancreaticoduodenectomy （PPPD） is unclear. We conducted a meta-analysis to investigate the relationship between DM and PF or *** SOURCES： Embase, MEDLINE and Cochrane databases were searched systematically for relevant articles from January 2005 to June 2013. The selected studies that examined clinical risk factors of PF or CR-PF were included. We created pooled estimates for our outcomes using the random-effects model. RESULTS： Sixteen observational clinical studies were included. Pooling of PF rates from ten studies revealed that DM was associated with a decreased risk of PF （P=0.01）. CR-PF rates from 8 studies showed no significant difference between DM and control group （P=0.14）. CONCLUSIONS： DM is not a risk factor for PF in patients undergoing PD or PPPD. On the contrary, patients without DM are at a higher risk of PF because the pancreases in these patients have more fatty tissue and the pancreas is soft.

关键词： pancreatic fistula diabetes postoperative complication

Peptidase Activities of Tripeptidyl Peptidase Ⅰ (TPP Ⅰ): Exopeptidase and Endopeptidase

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Chemical Research in Chinese Universities 2006年第1期22卷 65-67页

作者： DU Pei-ge AN Li-ping qiu Fang-ping LU gang Clinical Diagnosis Laboratory of Beihua University Jilin 132013 P. R. China College of Biological Engineering Changchun University of Technology Changchun 130012 P. R. China

The defect of TPP Ⅰ causes a disease, late infantile neuronal ceroid lipofuscinosis（LINCL, CLN2）. To investigate the bio-activity of tripeptidyl peptidase Ⅰ （TPP Ⅰ ） from rat kidneys, the effects of digestion of angiotensin Ⅱ （Ang Ⅱ ） and a synthetic endo-type substrate（ Gly^1-Lys-Pro^5-lie-Pro^5-Phe-Phe-Arg-Leu-Lys^10） via TPP I were ana- lyzed by HPLC and TOF-MS. The data suggest that the degradation rate of Ang I1 can reach 18. 2% by the rat TPP I and DRV（Asp-Arg-Val） can be released from N-termini of Ang Ⅱ within 16 h. In addition, the synthetic endotype substrate is cleaved at the same position between Phe6 and Phe^7. Accordingly, TPP Ⅰ shows two kinds of peptidase activities. One is a tripeptidyl peptidase activity and the other is a pepstatin insensitive carboxyl endopeptidase activity. Tripeptidyl peptidase activity and pepstatin insensitive carboxyl endopeptidase activity seem to be dual phases of one enzyme, TPP Ⅰ.

关键词： Rat TPP Ⅰ Angiotensin Ⅱ Endo-type substrate Endopeptidase activity

Advances of physics-based precision modeling and simulation for manufacturing processes

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Advances in Manufacturing 2013年第1期1卷 75-81页

作者： gang Wang yi-Ming Rong Department of Precision Instruments and Mechanology Tsinghua University Department of Mechanical Engineering Worcester Polytechnic Institute

The development of manufacturing process concerns precision, comprehensiveness, agileness, high efficiency and low cost. The numerical simulation has become an important method for process design and optimization. Physics-based modeling was proposed to promote simulations with a high accuracy. In this paper, three cases, on material properties, precise boundary conditions, and micro-scale physical models, have been discussed to demonstrate how physics-based modeling can improve manufacturing simulation. By using this method, manu- facturing process can be modeled precisely and optimized for getting better performance.

关键词： Material properties Multiscale analysis Physics-based modeling Manufacturing process

Alignment calibration and performance study of the STAR PXL detector

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Nuclear Science and Techniques 2017年第2期28卷 61-69页

作者： Long Ma Xin Dong Hao qiu Spiros Margetis Yu-gang Ma Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China University of Chinese Academy of Sciences Beijing 100049China Nuclear Science Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA Purdue University West Lafayette IN 47907 USA Kent State University Kent OH 44242 USA ShanghaiTech University Shanghai 200031 China

We report in this paper the alignment calibration of the STAR pixel detector(PXL) prototype for the RHIC2013 run and performance study of the full PXL detector installed and commissioned in the RHIC 2014 run. PXL detector is the innermost two silicon layers of the STAR heavy flavor tracker aiming at high-precision reconstruction of secondary decay vertex of heavy flavor particles. To achieve the physics goals, the calibration work was done on the detector with high precision. A histogram-based method was successfully applied for the alignment calibration, and the detector efficiency after alignment was studied using both p t p collision data and cosmic ray data.

关键词： Alignment calibration Heavy flavor tracker STAR

Sb nanoparticles encapsulated in N-doped carbon nanotubes as freestanding anodes for high-performance lithium and potassium ion batteries

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Rare Metals 2023年第2期42卷 449-458页

作者： Xiao-Ping Lin Fang-Fang Xue Zhi-gang Zhang qiu-Hong Li Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen UniversityXiamen361005China

Sb-based materials with high specific capacity have targeted as an alternative anode material for alkali metal ion ***,Sb nanoparticles embedded in hollow porous N-doped carbon nanotubes(Sb@N-C nanotubes)are used as freestanding anode for Li-ion batteries(LIBs)and K-ion batteries(PIBs).The Sb@N-C nanotubes demonstrate exceptional reversible capacity of643 mAh·g^(-1)at 0.1 A·g^(-1)with long cycle stability,as well as outstanding rate performance(219.6 mAh·g^(-1)at10 A·g^(-1))in *** the anode material of PIBs,they reveal impressive capacity of 325.4 mAh·g^(-1)at 0.1 A·g^(-1).The superior electrochemical properties mainly originate from the novel *** be specific,the obtained 3D connected network allows for quick ion and electron migration,and prevents the aggregation of Sb *** hollow porous nanotubes can not only accommodate the volume expansion of Sb nanoparticles during cycling,but also facilitate the infiltration of the electrolyte and reduce the ion diffusion *** work provides a new insight for designing advanced Sb-based anodes for alkali metal ion batteries.

关键词： Alkali metal ion batteries Freestanding electrode Hollow porous nanotube Sb@N-C nanotubes

An approximate analytical model for unconventional reservoir considering variable matrix blocks and simultaneous matrix depletion

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Petroleum Science 2024年第1期21卷 352-365页

作者： Kai-Xuan qiu Jia Li Dong Feng Shi-Ming Wei gang Lei Jiangmen Laboratory of Carbon Science and Technology Jiangmen529100GuangdongChina The Hong Kong University of Science and Technology(Guangzhou) Guangzhou511400GuangdongChina China University of Geosciences(Beijing) Beijing100083China China University of Petroleum(Beijing) Beijing102249China China University of Geosciences(Wuhan) Wuhan430074HubeiChina Shenzhen Research Institute China University of GeosciencesShenzhen518063GuangdongChina

In regard to unconventional oil reservoirs,the transient dual-porosity and triple-porosity models have been adopted to describe the fluid flow in the complex fracture *** has been proven to cause inaccurate production evaluations because of the absence of matrix-macrofracture *** addition,most of the existing models are solved analytically based on Laplace transform and numerical ***,an approximate analytical solution is derived directly in real-time space considering variable matrix blocks and simultaneous matrix *** simplify the derivation,the simultaneous matrix depletion is divided into two parts:one part feeding the macrofractures and the other part feeding the ***,a series of partial differential equations(PDEs)describing the transient flow and boundary conditions are constructed and solved analytically by ***,a relationship between oil rate and production time in real-time space is *** new model is verified against classical analytical *** the microfracture system and matrix-macrofracture communication is neglected,the result of the new model agrees with those obtained with the dual-porosity and triple-porosity model,***,the new model also has an excellent agreement with the numerical *** model is then applied to two actual tight oil wells completed in western Canada sedimentary *** identifying the flow regime,the solution suitably matches the field production data,and the model parameters are *** these output parameters,we can accurately forecast the production and even estimate the petrophysical properties.

关键词： Analytical solution Unconventional reservoir Variable matrix Simultaneous flow