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Magnesium matrix composite reinforced by nanoparticles-A review

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Journal of Magnesium and Alloys 2021年第1期9卷 57-77页

作者： k.B.Nie X.J.Wang k.k.Deng X.S.Hu k.wu State key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China

Significant progress has been made in magnesium-based composites during recent decades,especially for the appearance of magnesium matrix composite reinforced by *** nanoparticles added not only exhibit a good strengthening effect,but also maintain the initial toughness of the matrix,effectively balancing the contradiction between the strength and plasticity in the traditional magnesium matrix *** magnesium matrix nanocomposites with excellent mechanical properties have pushed the development of magnesium matrix composites to a new ***,it is very difficult to disperse the nanoparticles in metal melt especially in magnesium melt which is different from other metal melts and dangerous during the cast *** means that the preparation of magnesium matrix nanocomposite is extremely ***,the magnesium matrix nanocomposites possess a distinctive characteristic in deformation behavior,strengthening and toughening mechanism due to their special size effect of ***,this review will focus on the new preparation technologies,deformation behavior,mechanical properties and strengthening and toughening *** potential applications,development trends and future research ideas of magnesium matrix nanocomposite are also prospected.©2020 Published by Elsevier *** behalf of Chongqing University.

关键词： Magnesium matrix nanocomposite Microstructure Mechanical properties Strengthening mechanism

Ray wu's Golden Rules:How he achieved greatness in work,and in life

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Science China(Life Sciences) 2009年第2期52卷 101-107页

作者： Albert W. wu Christina C. wu Diana k. Sugg Health Policy and Management at the Johns Hopkins Bloomberg School of Public Health

Overview When Ray wu passed away on February 10, 2008, he was 79, working full-time in his lab at Cornell University, and was at or near the top of his long and noteworthy career. He had developed the first method for DNA sequencing and pioneered recombinant DNA technology. He had identified key genes related to stress tolerance in plants and was poised to apply these to boost crop yields of rice and

关键词： work Figure

A betatron tune measurement system based on bunch-by-bunch transverse feedback at the Duke storage ring

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Chinese Physics C 2013年第7期37卷 76-82页

作者：徐卫 W. Z. wu 李京祎何多慧 Y. k. wu National Synchrotron Radiation Laboratory (NSRL) University of Science and Technology of China FEL Laboratory TUNL and Department of Physics Duke University

To combat electron beam instabilities, a digital bunch-by-bunch transverse feedback （TFB） system has been developed for the Duke storage ring. While it is capable of suppressing transverse beam instabilities for multibunch operation, the TFB system has not been needed for typical operation of the Duke storage ring. To explore the great potential of this system, we have developed beam diagnostic techniques using the TFB, in particular, the TFB based tune measurement techniques. The tune measurement technique allows us to conduct fast chromaticity measurements, compared with the existing chromaticity measurement system using a network analyzer. This new tune measurement system also enables us to measure the bunch tune for multibunch operation of the Duke storage ring. With the TFB based tune measurement system, we have studied the tune stability of the electron beam in the Duke storage ring. This tune system has also been used to calibrate the tune knob for the Duke storage ring.

关键词： transverse feedback tune chromaticity

SUPERPLASTICITY IN SiC_w/Zk60 COMPOSITE

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Acta Metallurgica Sinica(English Letters) 2003年第3期16卷 217-220页

作者： F.Yan k.wu M.Zhao School of Muterials Science and Engineering Harbin Institute of Technology Harbin 150001ChinaSchool of Muterials Science and EngineeringHarbin Institute of Technology Harbin 150001ChinaSchool of Muterials Science and EngineeringHarbin Institute of Technology Harbin 150001China

The superplastic deformation behavior of SiCw/Zk60 composite was investigated at temperatures ranging from 573k to 723k and at initial strain rates ranging from 8.3x10-4s-1 to 8.3x10-2s-1. A maximum elongation of 200% with a m-value of 0.35 was obtained at 613k and a initial strain rate of 1.67x 10-2s-1. The apparent activation energy (98kJ/mol) approximates that for grain boundary diffusion (92kJ/mol) in magnesium. It is proposed that the dominant mechanism of superplastic deformation in the present composite is grain boundary sliding accommodated by diffusional transport, besides, interfacial sliding plays an important role in the superplastic deformation.

关键词： magnesium matrix composite superplasticity apparent activation energy

A Two-Dimensional Architecture for Fast Large-Scale Trapped-Ion Quantum Computing

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Chinese Physics Letters 2020年第7期37卷 5-10页

作者： Y.-k.wu L.-M.Duan Center for Quantum Information IIISTsinghua UniversityBeijing 100084China

Building blocks of quantum computers have been demonstrated in small to intermediate-scale *** one of the leading platforms,the trapped ion system has attracted wide attention.A significant challenge in this system is to combine fast high-fidelity gates with scalability and convenience in ion trap *** we propose an architecture for large-scale quantum computing with a two-dimensional array of atomic ions trapped at such large distance which is convenient for ion-trap fabrication but usually believed to be unsuitable for quantum computing as the conventional gates would be too *** gate operations far outside of the Lamb–Dicke region,we show that fast and robust entangling gates can be realized in any large ion *** gate operations are intrinsically parallel and robust to thermal noise,which,together with their high speed and scalability of the proposed architecture,makes this approach an attractive one for large-scale quantum computing.

关键词： Quantum computer operations

COMPARISON OF AMINOLEVULINIC ACID AND ITS METHYL ESTER MEDIATED PHOTOCYTOTOXICITY ON HUMAN NASOPHARYNGEAL CARCINOMA CELLS

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Journal of Innovative Optical Health Sciences 2012年第2期5卷 25-33页

作者： CHRISTINE M.N.YOW RICkY W.k.wu ZHENG HUANG Medical Laboratory Science Department of Health Technology Informatics Hong kong Polytechnic University Hong Kong SARChina Department of Radiation Oncology University of Colorado Denver COUSA MOE key Laboratory of OptoElectronic Science and Technology for Medicine Fujian Normal University FuzhouChina

Nasopharyngeal carcinoma(NPC)is a prevalent cancer in some areas of southern *** explore the potential of photodynamic therapy(PDT)for the treatment of NPC,a small molecule prodrug 5-aminolevulinic acid(ALA)and its methyl ester(MAL)mediated PDT was studied in *** results showed that human NPC cells were sensitive to both ALA-and MAL-mediated ***,ALA was more effective than MAL,possiblly due to a higher efficiency of ALA on producing endogenous protoporphyrin(PpIX)in NPC *** ALA nor MAL caused any significant *** ALA-based PDT might be a useful modality in the treatment ofNPC.

关键词： Aminolevulinic acid methylaminolevulinate nasopharyngeal carcinoma photodynamic therapy

Large pore size polyacrylonitrile membrane for ultrafiltration

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Journal of Environmental Sciences 2000年第4期12卷 478-481页

作者： wu, k. Qiu, P. Wang, Z. Wang, J. Rsrch. Center for Eco-Envtl. Sci. Chinese Academy of Sciences Beijing 100085 China

The effects of the components of solution for membrane casting and preparation conditions on the membrane performances are studied in this paper. Polyacrylonitrile (PAN) was used as polymer and DMAC as solvent. The ultrafiltration (UF) membranes whose cut-off of molecular weight is 150000 and flux of pure water reaches 150-200 ml/(cm2·h) were prepared by selecting proper components of solution for membrane casting and membrane preparation conditions.

关键词： Casting Molecular weight Polyacrylonitriles Pore size Water quality

Conditioning of BPM pickup signals for operations of the Duke storage ring with a wide range of single-bunch current

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Chinese Physics C 2014年第10期38卷 82-91页

作者：徐卫李京祎黄森林 W.Z.wu H.Hao P.Wang Y.k.wu National Synchrotron Radiation Laboratory (NSRL) University of Science and Technology of China Dept.of Physics Duke University and FEL labTriangle Universities Nuclear LaboratoryDurhamNC 27708-0308USA Institute of Heavy Ion Physics Peking University

The Duke storage ring is a dedicated driver for the storage ring based oscillator free-electron lasers（FELs）, and the High Intensity Gamma-ray Source（HIGS）. It is operated with a beam current ranging from about1 mA to 100 mA per bunch for various operations and accelerator physics studies. High performance operations of the FEL and γ-ray source require a stable electron beam orbit, which has been realized by the global orbit feedback system. As a critical part of the orbit feedback system, the electron beam position monitors（BPMs） are required to be able to precisely measure the electron beam orbit in a wide range of the single-bunch current. However, the high peak voltage of the BPM pickups associated with high single-bunch current degrades the performance of the BPM electronics, and can potentially damage the BPM electronics. A signal conditioning method using low pass filters is developed to reduce the peak voltage to protect the BPM electronics, and to make the BPMs capable of working with a wide range of single-bunch current. Simulations and electron beam based tests are performed. The results show that the Duke storage ring BPM system is capable of providing precise orbit measurements to ensure highly stable FEL and HIGS operations.

关键词： beam position monitor signal conditioning closed orbit feedback storage ring FEL

Synthesis and characteristics of nitric oxide spin probes

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Chinese Science Bulletin 1997年第20期42卷 1693-1699页

作者： Zhao, HT Liu, L Zhang, JZ Cong, JB wu, k Sun, CP Univ Sci & Technol China Grad Sch Dept Chem Beijing 100039 Peoples R China

NITRIC oxide (NO) is the important cell messenger molecule that regulates the central ner-vous, cardiovascular, endocrine and immunity systems. The study of NO not only canexplain many physiological phenomena, but also can provide new ways to prevent and treat alot of diseases. However, at present, most of the methods for assaying NO produced by or-ganism have some defects, for example, low sensitivity, no specificity, no convenience.

关键词： imidazole analogs nitrozide radical NO spin probe ESR.