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Characterization of plastic flow in two Zr-based bulk metallic glasses

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science china(Technological sciences) 2006年第4期49卷 414-424页

作者： XING Dongmei1,2. ZHANG Taihua1, LI Weihuo3 & WEI Bingchen3 1. State Key Laboratory of Nonlinear Mechanics (LNM), Institute of Mechanics, Chinese Academy of Sci- ences, Beijing 100080, china 2. college of Physics and {2. information science, tianjin normal university, tianjin 300074, china 3. National Microgravity Laboratory, Institute of Mechanics, Chinese Academy of sciences, Beijing 100080, china 1. State Key Laboratory of Nonlinear Mechanics (LNM) Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China 2. college of Physics and electronic {2. science Tianjin Normal University Tianjin 300074 China 3. National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

Plastic deformation behaviors of Zr65Al10Ni10Cu15 and Zr52.5Al10Ni10Cu15Be12.5 bulk metallic glasses (BMGs) are studied by using the depth-sensing nanoindentation, microindentation and uniaxial compression. The Be-containing BMG exhibits a signifi- cantly improved overall plastic strain compared with the Be-free alloy during compressive tests. Both BMGs show a loading-rate-dependent serrated flow during nanoindentation measurements, but the Be-containing alloy exhibits a much lower critical loading rate for the disappearance of the serration than the Be-free BMG. The shear band patterns de- veloped during plastic deformation are investigated by microindentation technique, wherein much higher shear band density is found in the Be-containing alloy than in the Be-free alloy, indicating an easier nucleation of shear bands in the former BMG. The dif- ference in the plastic deformation behavior of the two BMGs can be explained by a free volume model.

关键词： Bulk metallic glass, plastic deformation, shear band, nanoindentation.

Influence of modulation ratio on structure and properties of nanoscale ZrB_2.ZrAlN multilayered coatings

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science china(Technological sciences) 2010年第3期53卷 772-775页

作者： LI DeJun 1,KANG YuanBin 1,DONG Lei 1,DENG XiangYun 1,LIU Hao 2.&SUN XueLiang 2.1college of Physics and electronic {2. science,tianjin normal university,tianjin 300387,china 2.Department of Mechanical&Materials Engineering,university of Western Ontario,London ON,Canada 1. college of Physics and electronic {2. science Tianjin Normal University Tianjin 300387 China2. Department of Mechanical & Materials Engineering University of Western Ontario London ON Canada

ZrB2.ZrAlN multilayered coatings with various modulation ratios(t ZrB2.t ZrAlN)and constant modulation periods were prepared by magnetron sputtering system at room ***,XRD,surface profiler and nano-indenter were employed to investigate the influences of tZ rB 2.tZrAlNon the microstructure and mechanical properties of the *** interfaces and nanoscale multilayered modulation were confirmed by *** multilayer with modulation period of 40 nm and ratio of 3:1 displayed the highest hardness(36.4 GPa)and critical fracture load(76.477 mN)with lower *** polycrystalline structure and multilayered modulate structure were directly responsible for the enhanced mechanical properties.

关键词： ZrB2.ZrAlN multilayered coating magnetron sputtering modulation ratio nanoscale

Suitability evaluation for land reclamation in mining area:A case study of Gaoqiao bauxite mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 506-515页

作者： WANG Shi-dong1, 2. LIU Chang-hua2. ZHANG He-bing2.1. college of Resources science and Technology, Beijing {2. university, Beijing 100875, china 2. School of Surveying and Land information Engineering, Henan Polytechnic university, Jiaozuo 454000, china [a] college of Resources science and Technology Beijing Normal University Beijing 100875 China [b] School of Surveying and Land information Engineering Henan Polytechnic University Jiaozuo 454000 China

Suitability evaluation plays an important role in land reclamation because the choice of evaluation methods affects the accuracy and objectivity of the suitability evaluation results. Furthermore, it influences the decision-making related to land reclamation. An improved method, which is called limit comprehensive conditions method, was developed after different suitability evaluation methods were studied. Based on this method, the reclaimed land of the Gaoqiao bauxite mining area was evaluated. The Gaoqiao mining area was divided into seven evaluation units that were evaluated respectively by selecting evaluation factors and establishing grade standards. The results show that the proposed method is more applicable and easier to handle. Moreover, its evaluation results are more scientific compared with the traditional evaluation methods. The improved method can be beneficial to the rapid monitoring and the effective management of reclaimed land in the opencast mine area.

关键词： mining area land reclamation suitability evaluation Gaoqiao bauxite mine

The effects of modulation period,modulation ratio,and deposition temperature on microstructure and mechanical properties of ZrB_2.W multilayers

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science china(Technological sciences) 2010年第9期53卷 2350-2354页

作者： LIU MengYin,TAN Ming,LIU GuangQing,WANG HaiYuan,XUE FengYing,DENG XiangYun & LI DeJun college of Physics and electronic {2. science,tianjin normal university,tianjin 300387,china 1. college of Physics and electronic {2. science Tianjin Normal University Tianjin 300387 China

Monolithic ZrB2.W coatings and ZrB2.W multilayers with different modulation periods and modulation ratios were synthesized by ion beam assisted deposition at room temperature and 400°C.X-ray diffraction (XRD),scanning electron microscopy (SEM),surface profiler,and nanoindention were employed to investigate the influences of the deposition temperature and the modulation period on the growth,textures,interface structure,and mechanical properties of the *** results indicated that the multilayer with modulation period of 13 nm synthesized at room temperature possessed a higher hardness of 2..8 *** temperature gave a significant contribution to mechanical property *** 400°C-deposition temperature led to a maximum hardness and elastic modulus value of 32.1 and 399.1 GPa for ZrB2.W multilayer with a modulation period of 6.7 *** critical load increased to 42.8 mN and residual stress decreased to -0.7 GPa.A higher deposition temperature can cause an increase in interfacial atomic mixture and mobility of surface species,which induceds an increase in areal atomic density and dislocation *** results as well as small nanoscale grain sizes should be related to hardness increase.

关键词： ion beam assisted deposition nanoscale multilayers modulation period modulation ratio deposition temperature hardness

Synthesis of nanostructural ZnO using hydrothermal method for dye-sensitized solar cells

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science china(Technological sciences) 2010年第4期53卷 1146-1149页

作者： WANG ChunXiao1,2.ZHANG XiaoDan1,WANG DongFeng1,YANG ZhenHua1,2.JI WeiWei1,ZHANG CunShan2.& ZHAO Ying1 1 Institute of Photo-electronic Thin Film Devices and Technology of Nankai university,Key Laboratory of Photo-electronic information science and Technology(Nankai university),Ministry of Education,tianjin 300071,china 2.college of information Engineering,Hebei university of Technology,tianjin 300130,china 1. Key Laboratory of Photo-electronic information {2. and Technology (Nankai university) Ministry of Education Institute of Photo-electronic Thin Film Devices and Technology of Nankai University Tianjin 300071 China2. College of Information Engineering Hebei University of Technology Tianjin 300130 China

ZnO nanocrystals with different morphologies were successful synthesized by a simple hydrothermal method combined with and without hexadecyl trimethyl ammonium bromide(CTAB).The phases and morphologies of the products were measured using X-ray diffraction(XRD),scanning electron microscopy(SEM),and transmission electron microscopy(TEM),*** results indicated that the ZnO nanocrystals with different morphologies were of hexagonal wurtzite *** nanorods were obtained without using CTAB,and then the morphology of ZnO changed to ZnO nanoflower and the density of nanoflower became denser with the increase of CTAB *** nanoflower and ZnO nanorod as photoanode were applied to dye-sensitized solar cells(DSSC),*** nanoflower shows a higher dye loading,so DSSC with the use of the ZnO nanoflower possesses a higher conversion efficiency than ZnO nanorod.

关键词： DSSC ZnO

Modulation on the collective response behavior by the system size in two-dimensional coupled cell systems

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science china(Physics,Mechanics & Astronomy) 2006年第3期49卷 304-312页

作者： ZHANG Jiqian1, SHEN Chuansheng1,2.& CUI Zhifeng1 1. college of Physics and electronic {2., Anhui normal university, Wuhu 2.1000, china 2. Department of Educational Technology, Anqing Teachers college, Anqing 2.6011, china college of Physics electronic information Anhui Normal University Wuhu 241000 China Department of Educational Technology Anqing Teachers College Anqing 246011 China

By the intracellular calcium ionic minimal model proposed by Berridge, we investigated the collective response of two-dimensional (N×N) coupled cell systems to the external stimulation using numerical simulation methods. With a coupled intensity fixed and an appropriate coupled cell number chosen, the kinetic system size resonance was discovered. At the same time, it was found that the system size responding to the external stimulation for different coupled intensities transferred too, especially when the coupled intensity increased, the range of the corresponding system size extended. These phe- nomena illustrate that the coupled cell number and the coupled intensity can play con- structive roles in noisy coupled systems, by which the biology system would probably improve its capability to respond to the external stimulation.

关键词： cell coupling,collective response,system size resonance

Quantum secret sharing between multiparty and multiparty with four states

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science china(Physics,Mechanics & Astronomy) 2007年第5期50卷 572-580页

作者： YAN FengLi1, GAO Ting2.& LI YouCheng1 1 college of Physics and information Engineering, Hebei {2. university, Shijiazhuang 050016, china 2.college of Mathematics and information science, Hebei {2. university, Shijiazhuang 050016, china 1. college of Physics and information Engineering Hebei Normal University Shijiazhuang 050016 China 2. college of Mathematics and information {2. Hebei Normal University Shijiazhuang 050016 China

A protocol of quantum secret sharing between multiparty and multiparty with four states was presented. It was shown that this protocol can nullify the Trojan horse attack with a multi-photon signal, the fake-signal attack with Einstein-Podolsky- Rosen pairs, the attack with single photons, and the attack with invisible photons. In addition, the upper bounds of the average success probabilities were given for dishonest agent eavesdropping encryption using the fake-signal attack with any two-particle entangled states.

关键词： quantum secret sharing, security, Einstein-Podolsky-Rosen pairs

THz source based on optical Cherenkov radiation

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science china({2. sciences) 2012年第1期55卷 27-34页

作者： YAO JianQuan1,2.LIU PengXiang1,2.XU DeGang1,2.LV YingJin1,2.LV Da1,2.1Institute of Laser&Optoelectronics,college of Precision Instruments and Opto-electronic Engineering,tianjin university,tianjin 300072.china 2.ey Laboratory of Opto-electronics information Technology(tianjin university),Ministry of Education,tianjin 300072.china 1. Institute of Laser & Optoelectronics College of Precision Instruments and Opto-Electronic Engineering Tianjin University Tianjin 300072 China2. Ministry of Education Key Laboratory of Opto-electronics Information Technology (Tianjin University) Tianjin 300072 China

Terahertz(THz)technique has attracted considerable interest due to its broad application *** source is a crucial part of THz science and *** Cherenkov radiation in electro-optic crystals is a promising method of THz generation,because phase-matching is automatically *** this paper,we introduced two types of THz source based on optical Cherenkov radiation:both broadband and tunable *** mechanism of radiation was analyzed and recent development was reviewed in *** future of THz source based on optical Cherenkov radiation was also forecasted.

关键词： Terahertz source optical rectification dierence frequency generation Cherenkov radiation

The Detection of Defects in Optical Fibers Using a Hybrid Opto-electronic Correlator

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Chinese Journal of Lasers 2000年第3期9卷 15-21页

作者： LIU Yange LIU Wei ZHANG Yimo ZHOU Ge (college of Precision Instrument and Opto-electronics Engineering, {2. university Opto-electronic information science and Technology Lab., {2. 300072. china) 天津大学光电信息技术科学开放实验室天津

A hybrid opto-electronic correlator for detecting defects i n optical fibers is proposed. After the light from a He-Ne laser being expanded and filtered it is not collimated but directly passes a Fourier transform lens and illuminates a reference fiber and a test fiber at the same input plane. The Fourier transform spectrum of the two fibers is therefore obtained at the rear focal plane of the lens, where it is sampled via a CCD array connected with a computer through a frame grabber. The computer performs filter, inverse Fourier transform and setting threshold operation on classification. The system is an equivalent of joint transform correlator with a Fourier lens of long focal length. The experiment results for optical fibers having incoordinate defects are presented. The results indicate that the system can be used for fiber defect detection, and has the advantages of high identification, compact configuration, easy adjustment and flexible manipulation.

关键词： joint transform correlation Fourier transform optical fiber defect detection