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EFFECT OF ALLOYING ELEMENTS ON SENSITIVITY TO ENVIRONMENTAL EMBRITTLEMENT OF L1_2 INTERMETALLICS

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中国有色金属学会会刊：英文版 1999年第S1期9卷 117-124页

作者： x.J.Wan, x.Y.cheng and Y.x.Chen Materials Research Institute, Shanghai University, Shanghai 200072, China

The effect of Zr doping in Ni 3Al and B doping in Co 3Ti intermetallics on the sensitivity to moisture induced environmental embrittlement and on the hydrogen diffusivity was investigated. The results show that both B in Co 3Ti and Zr in Ni 3Al do not reduce the hydrogen diffusivity along the grain boundaries, therefore can not suppress the moisture induced environmental embrittlement. The above mentioned behavior of Zr in Ni 3Al and B in Co 3Ti is attributed to the fact that Zr and B are not segregated on the grain boundaries.

关键词： L1 2 intermetallics environmental embrittlement hydrogen diffusivity grain boundary segregation

Stochastic method to determine the scale and anomalous diffusion of gusts in a windy atmospheric boundary layer

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Chinese Science Bulletin 2014年第2期59卷 4890-4898页

作者： xueling cheng Fei Hu Qingcun Zeng State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of Sciences

In the atmospheric boundary layer, especially during strong wind period, the coherent structures are obvious and related to the direct interaction of the air masses with the ground. In this paper, we used the observation data during dust weather in Northwest Gansu to study the coherent structure and their ‘‘anomalous diffusion''. The structures in the atmospheric boundary layer included turbulent fluctuations and gusty wind disturbances, and could be denoted as ‘‘critical events' '. Their fractal dimensions were expressed by the complex index l of waiting times. Although the complex index can indicate the ability of the system to generate coherent structures, it has a strong dependence on the threshold marking the‘‘critical events' '. Hence, the continuous time random walk method was used to analyze the coherent structures. The scaling law of anomalous diffusion of coherent structures was obtained, and the diffusion scaling exponent H that indicated the ability of diffusion of different structures was analyzed. The exponents changed with structure scales which were affected by velocities and heights. At small scales, it was almost isotropic, and at large scales, the coherent structures were obvious and the diffusion was anomalous.

关键词：大气边界层结构反常扩散随机游动阵风相干结构扩散能力相互作用观测数据

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Shifts in water-level variation of Namco in the central Tibetan Plateau from ICESat and Cryo Sat-2 altimetry and station observations

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Science Bulletin 2015年第21期60卷 1287-1297页

作者： Chunqiao Song Qinghua Ye xiao cheng Institute of Tibetan Plateau Research (ITP) Chinese Academy of Sciences Department of Geography University of California State Key Laboratory of Remote Sensing Science College of Global Change and Earth System Science Beijing Normal University

The dynamics of high-altitude inland lakes in the Tibetan Plateau are sensitive indicators of climate change. Due to the remoteness and hard access, satellite altimetry becomes an effective approach to obtaining largescale and temporally continuous information of lake-level changes. The CryoSat-2 altimetry is expected to solve the current problem that earlier radar altimeters are only practical for monitoring large water bodies, while ICESat laser altimetry is available only for the period 2003-2009. In this study, the comparison of CryoSat-2 altimetry for Namco with in situ water-level data suggests a high cor- relation coefficient of 0.71 （P 〈 0.01）, with the mean error of -0.12 m and root-mean-square error of 0.18 m. Further, the combination of ICESat and CryoSat-2 altimetry data and in situ lake-level observations reveals a rapid water- level rise of 0.24 4- 0.04 m/year during 2003-2008 and then a slightly decreasing trend of -0.09 4- 0.04 m/year during 2009-2013. This study suggests that the CryoSat-2 altimetry has the potential of sustaining the fine observa- tions on Tibetan lakes, following the ICESat mission. Besides, the examination of four key climatic variables （temperature, precipitation, potential evapotranspiration, and relative humidity） during 1990-2013 indicates that the wetting climate over Namco Basin stagnated or even reversed around 2006, which may be tightly related to the slowing lake growth.

关键词： Lake Satellite altimetry CryoSat-2ICESat Tibetan Plateau - Climate change

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RESEARCH A NEW TOOL STEEL AND ITS PROPERTIES FOR MAKING WOOD-CHIP CUTTING KNIVES

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Acta Metallurgica Sinica(English Letters) 1999年第5期12卷 891-898页

作者： x.N.cheng,x.M.Luo and F.Jiang Department of Materials Engineering,Jiangsu University of Science and Technology,Nanjing 210013,China

On the basis of analyses of service conditions and properties requirements of wood chip cutting knives, an alloying scheme was formulated and a kind of new tool steel was developed. Parameters for its heat treating process and mechanical properties were systematically investigated and optimized. Satisfactory results were obtained on the knives in practice.

关键词： wood chip cutting material properties

12-钼磷酸与聚乙烯醇固容体的光致变色及其稳定性

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化学学报 2000年第3期58卷 277-282页

作者：程贤甦苏英草程传煊福建师范大学高分子研究所福州350007 福建师范大学化学系福州350007

以ESR,xPS,IR和UV-vis等手段,研究12-钼磷酸与聚乙烯醇黄色固容体的光致变色及其稳定性.由测试结果得知,该固容体的光致变蓝色是因其在紫外光照射下的光化学反应产物多价钼(Ⅵ,Ⅴ,Ⅳ)配合物呈蓝色,而另一种产物带部分羰基的聚乙烯醇为... 详细信息

以ESR,xPS,IR和UV-vis等手段,研究12-钼磷酸与聚乙烯醇黄色固容体的光致变色及其稳定性.由测试结果得知,该固容体的光致变蓝色是因其在紫外光照射下的光化学反应产物多价钼(Ⅵ,Ⅴ,Ⅳ)配合物呈蓝色,而另一种产物带部分羰基的聚乙烯醇为无色所致.随着它们的生成,后者产物因具有螺旋状结构能与前者产物发生包合作用,从而提高光致变色的稳定性.

关键词：稳定性固容体钼磷酸聚乙烯醇光化学反应

“钱学森之问”的误区——兼论全球化与大学的应对

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中国高教研究 2016年第1期 38-41页

作者：程星香港城市大学

"钱学森之问"背后的假设是大学应当培养杰出人才。但在高等教育已经进入大众化阶段的今天,大学管理者们需要考虑改变其精英培养模式,为学生将来成为杰出人才创造一个适合成长的环境。面对未来充满不确定性的、全球化的职场,大学毕业生... 详细信息

"钱学森之问"背后的假设是大学应当培养杰出人才。但在高等教育已经进入大众化阶段的今天,大学管理者们需要考虑改变其精英培养模式,为学生将来成为杰出人才创造一个适合成长的环境。面对未来充满不确定性的、全球化的职场,大学毕业生必须学会读书、思考;沟通、协调;择业、转业。

关键词：精英教育大众教育全球化国际化人才

海藻酸铜膜表面的配位结构及催化MMA聚合的性能

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化学学报 2000年第4期58卷 407-413页

作者：程贤甦关怀民苏英草福建师范大学高分子研究所福州350007

将海藻酸钠(SA)与CuCl_2·2H_2O反应得到一种配位聚合物海藻酸铜(Cu-An).以ESR、电导率、IR和xPS方法对此配位聚合物进行表征,确定了组成与结构;同时研究了甲基丙烯酸甲酯(MMA)在该配位聚合物膜、HSO_3^-和水体系催化引发作用下的聚合... 详细信息

将海藻酸钠(SA)与CuCl_2·2H_2O反应得到一种配位聚合物海藻酸铜(Cu-An).以ESR、电导率、IR和xPS方法对此配位聚合物进行表征,确定了组成与结构;同时研究了甲基丙烯酸甲酯(MMA)在该配位聚合物膜、HSO_3^-和水体系催化引发作用下的聚合反应历程.结果表明,配位聚合物的中心离子Cu^(2+)与两个海藻酸(An)链节单元上的两个羧羟基氧原子和两个离解氢原子的羧羟基氧原子以共价型配位,配位数为***在上述的催化引发体系中是按照自由基加聚反应历程进行聚合的,PMMA呈无规结构.Cu-An在催化引发体系中起着催化剂的配位催化作用.

关键词：海藻酸配位聚合物海藻酸铜 MMA 自由基聚合

Hydrogen adsorption properties of nanoporous SiC fibers

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Hydrogen adsorption properties of nanoporous SiC fibers

辛德毕斯病毒：一种多种动物细胞中高效表达外源基因...

第九届全国氢能学术会议

作者： Z.Y.Chu,R.A.He,H.F.cheng,x.D.Li,x.B.Zhang National University of Defence Technology,China

We successfully prepared nanoporous SiC fibers from polymer precursors,with average pore diameters in the range of 1.3-1.8nm and surface areas more than 600m/*** adsorption properties of some typical synthesized fibers were studied,as compared with those of carbon nanotubes(CNTs).The results showed that the fibers with more nanopores are

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来源： cnki会议评论

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cnki会议

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国外医学（分子生物学分册） 1990年第3期12卷 135-137页

作者： cheng.,x 房德兴