PARAMAGNETIC MEISSNER EFFECTS IN MELT-TEXTURED Y_(0.99)Nd_(0.01)Ba_2Cu_3O_(7-y)SUPERCONDUCTOR

The paramagnetic Meissner effect (PME) was observed on the field-cooled M-T curvesof melt-textured Y0.99Nd0.01Ba2Cu3O7-y in applied magnetic fields from 1kOe toJ0kOe. In the magnetic field below 1kOe, the sample undergoes the typical transi-tion from the normal state to the superconducting state when it was cooled down. Theapplied magnetic fields in which the PME occurs, are very high compared with thefields reported in literatures. We propose that the occurrence of the PME may be dueto a phase transition of flux vortices in the superconductors.     

喷射成形高温合金沉积态组织的形成与演变

对喷射成形高温合金的组织形成及其从雾化过程的树枝晶向等轴晶组织的演变过程进行了分析，结果表明，半液态层中发生的枝晶破碎，重熔所造成的核心增殖作用为等轴晶组织的形成提供了大量结晶核心，在此基础上枝晶臂的合并，粗化以及未严重固相枝晶的粗化和均匀化产生了喷射成形材料所持有的非枝非等轴晶组织。     

STRUCTURAL DETERMINATION OF TITANIUM-OXIDE NANOPARTICLES BY X-RAY ABSORPTION SPECTROSCOPY

As a potential application of titanium-oxide nanoparticles, it is extremely important to investigate a detailed picture of the surface and interior structural properties of nanocrystalline materials, such as rutile and anatase with diameters 7.0 and 4.5nm, respectively. X-ray absorption spectroscopy has been used to identify the local Ti environment and related electronic structure. We combine the experimental results at the Ti edge in both bulk and nano-crystals to determine the lattice distortion in terms of differently characteristic preedge features and the variation in the multiple-scattering region of X-ray absorption near-edge structure (XANES) spectra. The relationship between the transition peaks and the surface-to volume ratio is also discussed.     

THE APPARENT VISCOSITY OF SEMI-SOLID AZ91D ALLOY AT STEADY STATE

The rheological behavior of semi-solid AZ91D at steady state is studied using a Couette type viscometer in the present paper. The results show that the apparent viscosity of semi-solid AZ91D at the steady state increases with the solid fraction increasing, and goes up sharply when the solid fraction reaches a certain value, which is called critical fraction. In addition, the apparent viscosity of semi-solid AZ91D at the steady state takes on a distinct downtrend with the shearing rate increasing, which indicates a strong shear thinning property. In addition, the critical solid fraction becomes higher under larger shearing rate, owing to the more globular shape of the solid particles. Based on the present experiment results, an empirical equation is built as that, relating the steady state apparent viscosity of semi-solid AZ91D with the solid fraction fs andshearing rate (?) at the same time: ηapp=10.74exp(6.95fs)(?)-0.86.     

Autonomous Visual Measurement for Accurate Setting of Workpieces in Robotic Cells

This paper introduces a new method of adapting the virtual world of an offline programming model to an actual robotic cell by attaching a CCD camera to the robot. This method requires no specific camera attachment location or optical camera calibration. Furthermore, there is no operational requirement for setting robotic camera location. Robot motion is autonomously generated to identify the camera view line. The view line is adjusted to pass through the designated target point, utilizing visual feedback motion control. This method calibrates reference points between the virtual world of an offline model to an actual robotic cell.     

VCSTalk：基于DEA的开源软件开发人员效率评价工具*

介绍了VCSTalk的具体设计和实现架构,并展示了它用于评价若干开源软件项目中的开发人员效率的一个具体实例.     

Windows平台下外围存储设备信息监控*

针对目前使用内部网络的外围存储设备时存在的安全问题,研究了现行外围存储设备使用中的安全保护措施,分析了现有技术方法的欠缺,提出主机外围设备使用统一管理监控的思想,并采用文件系统过滤驱动技术,设计实现了主机外围存储设备信息监控系统.     

Stimuli-Responsive Nanomaterials for Smart Tumor-Specific Phototherapeutics

Phototherapy, a type of photoresponsive regulation of biological activities, together with additional stimuli-responsive features, offers significant potential for enhancing the precision and efficacy of cancer treatments. To achieve tumor-specific therapeutics, numerous studies have focused on the development of smart phototherapeutic nanomaterials (PNMs) that can respond to endogenous pathological characteristics (e. g., mild acidity, the overproduction of glutathione, the overproduction of hydrogen peroxide, the overexpression of specific surface receptors, etc.) present in the tumor and/or exogenous stimuli. Such responsiveness can effectively improve the physicochemical properties, cellular uptake, tumor-targeting performance, and pharmacokinetic profile of PNMs. Herein, we will systematically discuss recent advances in this field. Moreover, potential challenges and future directions in the development of stimuli-responsive PNMs are also presented to support the development of this emerging cutting-edge research area.     

Effect of SiO2 Addition on Chromium Transitions in Borate Glasses

Silicon - Melt-quenching technique was used to prepare borosilicate glasses of composition xSiO2- (75-x) B2O3–24.7Li2O-0.3Cr2O3 (x = 0, 10, 20, 30, 40 and 50 mol%). With...     

The dynamic evolution of aggregated lithium dendrites in lithium metal batteries

Lithium (Li) metal anodes promise an ultrahigh theoretical energy density and low redox potential,thus being the critical energy material for next-generation batteries.Unfortunately,the formation of Li den-drites in Li metal anodes remarkably hinders the practical applications of Li metal anodes.Herein,the dynamic evolution of discrete Li dendrites and aggregated Li dendrites with increasing current densities is visualized by in-situ optical microscopy in conjunction with ex-situ scanning electron microscopy.As revealed by the phase field simulations,the formation of aggregated Li dendrites under high current den-sity is attributed to the locally concentrated electric field rather than the depletion of Li ions.More specif-ically,the locally concentrated electric field stems from the spatial inhomogeneity on the Li metal surface and will be further enhanced with increasing current densities.Adjusting the above two factors with the help of the constructed phase field model is able to regulate the electrodeposited morphology from aggregated Li dendrites to discrete Li dendrites,and ultimately columnar Li morphology.The methodol-ogy and mechanistic understanding established herein give a significant step toward the practical appli-cations of Li metal anodes.