Enhanced linear magneto-resistance near the Dirac point in topological insulator Bi2(Te1−xSex)3 nanowires

Nano Research - We report the composition and back-gate voltage tuned transport properties of ternary compound Bi2(Te1−xSex)3 nanowires synthesized by chemical vapor deposition (CVD). It is...     

Variability of complementary relationship and its mechanism on different time scales

In the complementary relationship (CR) between actual and potential evapotranspiration, wet envi- ronment evapotranspiration (Ew) is usually calculated using the Priestley-Taylor (P-T) equation. Based on the data obtained from 38 catchments of the Haihe River basin and the Weishan experiment site in Shandong Province of China, this study has found variations in the Priestley-Taylor parameter α (e.g. increase in values with increase in the amount of precipitation on annual scale, seasonal fluctuation noted t...     

满足匹配律的策略参数搜索决策模型

匹配律是决策理论的基本定律之一,它建立了对备选目标的偏好与所获奖励之间的对应关系.通过构建获得匹配律的策略模型,研究了该定律成立的可能机制.基于再励学习理论,提出了通过调整策略参数以满足决策目标的策略搜索模型.在该策略模型的基础上,通过设定简单的假设条件推导出满足匹配律的策略算法.理论分析和数值仿真结果均验证了算法的正确性.另一方面利用该算法模拟了经典的心理学与神经生理学的匹配行为实验.研究结果不仅对匹配行为给出了合理的解释,也为建立基于奖励的决策模型提供了一种有效的理论建模方法.     

Thermodynamic watershed hydrological model: Constitutive relationship

The representative elementary watershed (REW) approach proposed by Reggiani et al. was the first attempt to develop scale adaptable equations applicable directly at the macro scale. Tian et al. extended the initial definition of REW for simulating the energy related processes, and re-organized the deriving procedure of balance equations so that additional sub-regions and substances could be easily incorporated. The resultant ordinary differential equation set can simulate various hydrological processes in a physically reasonable way. However, constitutive and geometric relationships have not been developed for Tian et al.’s equation set, which are necessary for the thermodynamic watershed hydrological model to apply in hydrological modeling practice. In this work, the constitutive equations for mass exchange terms and momentum exchange terms were developed as well as geometric relationships. The closed ordinary differential equation set with nine equations was finally obtained. Supported by the National Natural Science Foundation of China (Grant No. 50509013)     

Structural topology optimization: Extensibility and attainability

Extensibility and attainability of topology optimization are discussed by investigating a variety of simultaneous topology opti-mization methods extended from the standard formulation. First, the state of the art is highlighted through systematic classification of developed methods, such as simultaneous topology optimizations of microstructure and macrostructure, structure and supports, structure and design-dependent loads, structure and locations of involved components. Second, some recent results about simultaneous topology optimization of structure and applied loads are presented. It is shown that the simultaneous topology optimization is an integrated methodology that extends the concept of standard topology optimization in the sense of systematic design. The presence of more than one kind of design variable of different nature makes the optimization problem complex but enlarges the design space to attain the optimization.     

光纤在医学照明上的应用

介绍了多组分玻璃光纤、石英光纤和聚合物光纤在医学照明上的应用,现今医学上应用的光纤传光束以多组分玻璃光纤为主,传光束直径多在0.50-6mm之间,光纤传光束能将光直接引入到需要照明观察或诊断部位,具有体积小、操作方便和冷光照明的特点,典型的光纤传光束照明应用包括内窥镜、五官科用检查镜和手术用光纤照明镜等,光纤在医学上的应用解决了传统医疗器械的照明问题,使医用器械的性能得到很大改善和提高。     

通电加热快餐粥的研制

研究了通电加热快餐粥的配方和生产工艺,对其进行了感官评分及营养素含量和耗电量测定,并与普通电炉加热快餐粥进行了比较。实验结果表明,通电加热快餐粥的感官评分和营养素含量明显高于电炉加热快餐粥,而耗电量低于电炉加热快餐粥。     

重庆金源大饭店

酒店的设计大气、典雅、力求使用现代的材料与灯光的配合，通过简洁、大方的造型营造富有生命力和时代感的空间。     

Hopkinson杆三点弯曲试验中试样与支座接触状态分析

分析Hopkinson杆动态断裂试验中试样与支座的接触状态.研究表明,试样与支座的接触状态取决于试样几何和材料性能参数.在按现行三点弯曲试验方法进行的试验中,确实存在试样与支座脱离接触的现象,并且试样在支座开始受力前起裂.因此,所谓Hopkinson杆三点弯曲试验实际上是单点弯曲试验.并给出标准Charpy试样在Hopkinson杆动态断裂试验中试样与支座之间保持接触的条件.     

电子产品波峰焊使用的含铅和无铅钎料的生命周期影响

本文介绍了由美国环境保护署（EPA）和美国电子工业联合资助进行的含铅和两种无铅替代钎料的生命周期评价结果.报导的影响值为波峰焊中的16个不同的环境条目.评价的钎料棒有锡铅、锡银铜和锡铜.结果认为锡铅钎料在4个方面的影响值高于无铅钎料,而另5个方面却低于无铅钎料.使用及应用阶段对多数影响值起主要作用.而对不同的钎料,上游阶段和用后处理工艺也对几个特定的影响条目起重要作用;文中还报导了银的生产影响和填埋渗滤数据的敏感性分析.