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Corrosion and electrochemical behavior of as-cast Mg-5Y-7Gd-1Nd-0.5Zr magnesium alloys in 5%NaCl aqueous solution

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Progress in Natural Science:Materials International 2011年第4期21卷 314-321页

作者： Xin ZHANG~(1,2,3),Kui ZHANG~1,Xing-gang LI~1,Cong WANG~4,Hong-wei LI~(2,3),Chang-shun WANG~(2,3),Xia DENG~1 1.State Key Laboratory for Fabrication and Processing of Nonferrous Metals, beijing General Research Institute for Nonferrous Metals,beijing 100088,china 2.beijing Engineering Research Center for Advanced Manufacturing and Evaluation of Special Vehicle Parts,beijing 100072,china 3.Institute of Technology,beijing North Vehicle Group Corporation,beijing 100072,china 4.Fengtai Military Representative Office,beijing Military Representative Office,PLA,beijing 100072,china [a] State Key Laboratory for Fabrication and Processing of Nonferrous Metals Beijing General Research Institute for Nonferrous Metals Beijing 100088 China [b] beijing Engineering Research Center for Advanced Manufacturing and Evaluation of Special Vehicle Parts Beijing 100072 China [c] Institute of Technology Beijing North Vehicle Group Corporation Beijing 100072 China [d] Fengtai Military Representative Office Beijing Military Representative Office PLA Beijing 100072 China

The corrosion mechanism of the as-cast Mg-5Y-7Gd-1Nd-0.5Zr magnesium alloy immersed in 5%NaCl aqueous solution was investigated by electrochemical test and *** electrochemical results indicate that the corrosion resistance of Mg-5Y-7Gd-1Nd-0.5Zr alloy in 5%NaCl aqueous solution gradually deteriorates with immersion time increasing from 2 h,24 h,60 h,to 108 h,which is consistent with the SEM observation of corrosion *** Cl-anion leads to the initiation and development of the corrosion pits,and Mg-5Y-7Gd-1Nd-0.5Zr alloy exhibits filiform type of attack under significant anodic control of magnesium solution *** corrosion potential becomes noble with increasing immersion time.

关键词： magnesium alloys Mg-5Y-7Gd-1Nd-0.5Zr corrosion electrochemical behavior

Biogas recovery from microwave heated sludge by anaerobic digestion

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Science china(Technological Sciences) 2010年第1期53卷 144-149页

作者： QIAO Wei1,WANG Wei2,ZHU CuiPing3 & ZHANG ZhongZhi1 1 College of Chemical Science and Engineering,china University of Petroleum,beijing 102249,china 2 Department of Environmental Science and Engineering,Tsinghua University,beijing 10084,china 3 J & K china Cleaning Energy Technology Co.Ltd.,beijing 100085,china 1. College of Chemical Science and Engineering China University of Petroleum Beijing 102249 China2. Department of Environmental Science and Engineering Tsinghua University Beijing 10084 China3. J & K China Cleaning Energy Technology Co. Ltd. Beijing 100085 China

Biogas generated from sewage sludge,livestock waste,and food waste by anaerobic digestion is a valuable renewable energy ***,conventional anaerobic digestion is not an efficient process.A long hydraulic retention time and low biogas recovery rate hinder the applications of those *** effective pretreatment method to destroy sludge microbial cells has been one of the major concerns regarding improvement of the biogas *** article focuses on the effects of microwave heating on sludge anaerobic *** suspended solid(VSS) and chemical organic demand solubilization of heated sludge were *** heating was found to be a rapid and efficient process for releasing organic substrates from *** increase of organic dissolution ratio was not obvious when holding time was over 5 min with microwave *** effect of the VSS solubilization was primarily dependent on heating *** highest value of VSS dissolving ratio,36.4%,was obtained at 170°C for 30 *** COD dissolving ratio was about 25% at 170°*** organic carbon of treated sludge liquor was 1.98 and 2.73 g/L at 150°C and 170°C for 5 min,respectively.A biochemical methane potential(BMP) test of excess sludge and a mixture of primary and excess sludge demonstrated an increase in biogas *** total biogas from microwave treated mixture sludge increased by 12.9% to 20.2% over control after 30 days of *** production was 11.1% to 25.9% higher for excess sludge than for untreated *** VS removal ratios of mixture sludge and excess sludge were 12% and 11% higher,respectively,compared to the untreated sludge.

关键词： biogas recovery microwave heating sludge anaerobic digestion

A TTCN-3-based protocol testing system and its extension

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Science in china(Series F) 2008年第11期51卷 1703-1722页

作者： YIN Xia1,3,WANG ZhiLiang2,3,JING ChuanMing1,3 & SHI XinGang2,3 1 Department of Computer Science and Technology,Tsinghua University,beijing 100084,china 2 Network Research Center,Tsinghua University,beijing 100084,china 3 Tsinghua National Laboratory for Information Science and Technology(TNList) ,beijing 100084,china 1. Department of Computer Science and Technology Tsinghua University Beijing 100084 China 3. ]Tsinghua National Laboratory for Information Science and Technology (TNList) Beijing 100084 China 2. Network Research Center Tsinghua University Beijing 100084 China

The protocol testing technology used in the next generation Internet should satisfy some new challenges and requirements. This paper focuses on the test suite description and test implementation techniques. TTCN-3 is chosen as the test suite description language and extended in both syntax and semantics to satisfy the requirements of protocol robustness testing. PITSv3, a protocol integrated testing system based on TTCN-3, is developed, and the extensions for robustness testing are implemented. Finally, two practical test applications are presented.

关键词： protocol testing TTCN-3 PITSv3 robustness testing

Spectral integration and perception of Chinese back vowel /γ/

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Science china(Information Sciences) 2010年第11期53卷 2300-2309页

作者： YU ShuiYuan1, CHEN YuDong2 & WU JieRu3 1School of Computer, Communication University of china, beijing 100024, china 2International College for Chinese Language Studies, Communication University of china, beijing 100024, china 3School of Presentation Art, Communication University of china, beijing 100024, china 1. School of Computer Communication University of China Beijing 100024 China2. International College for Chinese Language Studies Communication University of China Beijing 100024 China3. School of Presentation Art Communication University of China Beijing 100024 China

The first two formants of the back vowels of many languages, such as English, are often close in frequency within the critical 3.5-Bark distance and are phonetically equivalent to a single intermediate formant. This phenomenon is called spectral integration. The integrated spectral peak is related more directly to phonetic quality than to acoustic formants and is therefore an important cue for determining the phonetic quality of vowels. The Chinese vowel /γ/ is a back vowel, but its first two formants are commonly separated by more than the critical distance. What are the perceptual cues for this vowelDoes the spectral integration phenomenon influence its perceptionThis paper describes a series of identification experiments and rating experiments on the influences of the distance, spectral shape, and relative amplitude of the first two formants on the phonetic quality of /γ/. The results show that all stimuli with a two-peaked spectral shape are perceived as /γ/ whenever the first two formants are separated by the critical Bark distance or beyond. When the two formants are separated by roughly the critical distance, only those stimuli with sharp formants are perceived as /γ/, while stimuli with trapezoidal or single-peaked spectral shapes are not perceived as /γ/. Specifically, when the second formant is 10 dB higher than the first, the spectral integration phenomenon influences formant perception, and the stimulus is not perceived as /γ/; on the contrary, when the second formant is 0-20 dB lower than the first, the stimulus is perceived as /γ/, and spectral integration does not occur. That is to say, spectral integration occurs asymmetrically about the relative amplitudes of the first two formants. In a word, the Chinese vowel /γ/ is a back vowel, but spectral integration does not occur in the perception of its first two formants. Two individual formants are necessary for the phonetic color of the Chinese vowel /γ/. This vowel is different from the back vowels of w

关键词： spectral integration Chinese back vowel /γ/ back vowel critical distance

Multi-level decollement zones and detachment deformation of Longmenshan thrust belt,Sichuan Basin,southwest china

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Science china Earth Sciences 2008年第S2期51卷 32-43页

作者： TANG LiangJie1,2,3,YANG KeMing4,JIN WenZheng1,2,3,L ZhiZhou4 & YU YiXin1,2,3 1 State Key Laboratory of Petroleum Resource and Prospecting,china University of Petroleum,beijing 102249,china 2 Key Laboratory for Hydrocarbon Accumulation Mechanism,china University of Petroleum,Ministry of Education,beijing 102249,china 3 Basin and Reservoir Research Center,china University of Petroleum,beijing 102249,china 4 Southwest Division Company,SINOPEC,Chengdu 610081,china 1. State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China 2. Key Laboratory for Hydrocarbon Accumulation Mechanism China University of Petroleum Ministry of Education Beijing 102249 China 3. Basin and Reservoir Research Center China University of Petroleum Beijing 102249 China 4. Southwest Division Company SINOPEC Chengdu 610081 China

As is well known that many decollement layers were developed in the Longmenshan thrust belt,Si-chuan Basin,china. Through field investigation,explanation of seismic profiles and analysis of the balanced sections,we can divide the decollement zones into 3 categories: (1) the deep level decolle-ment zones,including the crust-mantle decollement layer,intracrustal decollement layer,and presinian basal decollement layer. The main structural styles of their deformation are the crust-mantle decoup-ling detachment deformation,the basal ductile shear deformation,etc.; (2) the middle level decollement zones,including the Cambrian-Ordovician decollement layer,the Silurian decollement layer,etc.,the main structural styles of their deformation are the isopachous fold,the angular fold,the saddle struc-ture,and the combination styles of them; and (3) the shallow level decollement zones,including the Xujiahe Formation decollement layer of Upper Triassic and the Jurassic decollement layers,the main structural styles of their deformation are the thrust-nappe tectonic,the pop-up,the triangle zone ,the duplex,etc. Multi-level decollement zones not only made the Longmenshan thrust belt develop many different deformation styles from deep place to shallow place,but also made some local areas have the superimposition of the tectonic deformation apparently. This study indicates that the multi-level de-collement zones have a very important effect on the shaping and evolution of the Longmenshan thrust belt.

关键词： decollement layer structural styles multi-level decollement zones Longmenshan thrust belt

The role of the DLPFC in inductive reasoning of MCI patients and normal agings:An fMRI study

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Science china(Life Sciences) 2009年第8期52卷 789-795页

作者： YANG YanHui1,3,LIANG PeiPeng2,3,LU ShengFu2,3,LI KunCheng1,3 & ZHONG Ning2,3,4 1 Xuanwu Hospital,Capital Medical University,beijing 100053.china 2 The International WIC Institute,beijing University of Technology,beijing 100124,china 3 beijing Municipal Lab of Brain Informatics,beijing 100124,china 4 Department of Life Science and Informatics,Maebashi Institute of Technology,Maebashi 371-0816,Japan Xuanwu Hospital Capital Medical University Beijing 100053 China The International WIC Institute Beijing University of Technology Beijing 100124 China beijing Municipal Lab of Brain Informatics Beijing 100124 China Department of Life Science and Informatics Maebashi Institute of Technology Maebashi 371-0816 Japan

Previous studies of young people have revealed that the left dorsolateral prefrontal cortex(DLPFC) plays an important role in inductive *** fMRI experiment was performed in this study to examine whether the left DLPFC was involved in inductive reasoning of MCI patients and normal agings,and whether the activation pattern of this region was different between MCI patients and normal *** fMRI results indicated that MCI patients had no difference from normal agings in behavior performance(reaction time and accuracy) and the activation pattern of ***,the BOLD response of the DLPFC region for MCI patients was weaker than that for normal agings,and the functional connectivity between the bilateral DLPFC regions for MCI patients was significantly higher than for normal *** together,these results indicated that DLPFC plays an important role in inductive reasoning of agings,and the functional abnormity of DLPFC may be an earlier marker of MCI before structural alterations.

关键词： mild cognitive impairment functional MRI inductive reasoning

Synthesize TiO_2 microspheres self-assembled from nanorods via hydrothermal treatment

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Science china Chemistry 2007年第2期50卷 175-178页

作者： ZHANG YiBing1,2,FENG XinJian3 & JIANG Lei2,3 1 Shangrao Teachers’ College,Shangrao 334001,china 2 National Center for Nanoscience and Nanotechnology,beijing 100080,china 3 Institute of Chemistry,Chinese Academy of Sciences,beijing 100080,china 1. Shangrao Teachers’ College Shangrao 334001 China 2. National Center for Nanoscience and Nanotechnology Beijing 100080 China 3. Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

The TiO2 microspheres were deposited on the glass substrates under certain conditions via hydro-thermal reaction using 0.15 mol·L?1 TiCl3 saturated NaCl aqueous solution adding urea as an additive. The TiO2 is characterized rutile by results of SEM,TEM and XRD techniques,the TiO2 microspheres are large scale assembled from TiO2 nanorods. The affections on the products by the factors of the con-tents of urea being an additive(the key techniques) ,the reaction temperature,the reaction time and the concentration of TiCl3 were studied. The optimum condition was found,and the mechanism of reac-tions was discussed also.

关键词： TiO2 self-assembly nanorods microsphere hydrothermal reaction

Exotic structure of the third excited state in^(21)Na

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Chinese Science Bulletin 2005年第23期50卷 2677-2680页

作者： LI Xihan1,2,3, LIANG Yujie1,2,3, DENG Fuguo1,2,3, LIU Zuhua1,4 & ZHOU Hongyu1,2,3 1. Key Laboratory of Beam Technology and Material Modification of Minister of Education, beijing Normal University, beijing 100875, china 2. Institute of Low Energy Nuclear Physics, and Department of Material Science and Engineering, beijing Normal University, beijing 100875, china 3. beijing Radiation Center, beijing 100875, china 4. china Institute of Atomic Energy, beijing 102413, china Key Laboratory of Beam Technology and Material Modification of Minister of Education Beijing Normal University Beijing 100875 China Institute of Low Energy Nuclear Physics and Department of Material Science and Engineering Beijing Normal University Beijing 100875 China beijing Radiation Center Beijing 100875 China china Institute of Atomic Energy Beijing 102413 China

The probability of the last proton being out of the binding potential, P and the root-mean-square (rms) ra- dius (1/2= of the third excited state in 21Na are calcu- lated by means of asymptotic normalization coefficient (ANC) method with the experimental date existing. The results are P=54.73% and 1/2=5.28 fm respectively. The P value and the contribution of the asymptotic part to the 1/2 are compared with those of several other low energy states in 21Na. It is found that the valence particle in the third excited state has an obvious larger P than those of other states. The density distribution of the valence proton in this state is also compared with the nucleons in the nuclear core 20Ne, and a far extended tail can be seen clearly. These results show that the third ex- cited state in 21Na is a proton halo state.

关键词：钠第三激发态外部结构有效半径密度分布渐近标准化系数

Multiparty simultaneous quantum identity authentication with secret sharing

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Science china(Physics,Mechanics & Astronomy) 2008年第3期51卷 321-327页

作者： YANG YuGuang1,2,WEN QiaoYan3 & ZHANG Xing4,5 1 College of Computer Science and Technology,beijing University of Technology,beijing 100022,china 2 State Key Laboratory of Information Security (Graduate University of the Chinese Academy of Sciences),beijing 100049,china 3 School of Science,beijing University of Posts and Telecommunications,beijing 100876,china 4 Institute of Electronic Technology,Information Engineering University,Zhengzhou 450004,china 5 Trusted Computing Laboratory,beijing University of Technology,beijing 100022,china College of Computer Science Technology Beijing University of Technology Beijing 100022 China State Key Laboratory of Information Security [Graduate University of the Chinese Academy of Sciences] Beijing 100049 China School of Science Beijing University of Posts Telecommunications Beijing 100876 China Institute of Electronic Technology Information Engineering University Zhengzhou 450004 China Trusted Computing Laboratory Beijing University of Technology Beijing 100022 China

Two multiparty simultaneous quantum identity authentication (MSQIA) protocols based on secret sharing are presented. All the users can be authenticated by a trusted third party (TTP) simultaneously. In the first protocol,the TTP shares a random key K with all the users using quantum secret sharing. The ith share acts as the authentication key of the ith user. When it is necessary to perform MSQIA,the TTP generates a random number R secretly and sends a sequence of single photons encoded with K and R to all the users. According to his share,each user performs the corresponding unitary operations on the single photon sequence sequentially. At last,the TTP can judge whether the impersonator exists. The sec-ond protocol is a modified version with a circular structure. The two protocols can be efficiently used for MSQIA in a network. They are feasible with current technol-ogy.

关键词： quantum identity authentication secret sharing quantum cryptography