VEDA: a web-based virtual environment for dynamic atomic force microscopy

We describe here the theory and applications of virtual environment dynamic atomic force microscopy (VEDA), a suite of state-of-the-art simulation tools deployed on nanoHUB (www.nanohub.org) for the accurate simulation of tip motion in dynamic atomic force microscopy (dAFM) over organic and inorganic samples. VEDA takes advantage of nanoHUB's cyberinfrastructure to run high-fidelity dAFM tip dynamics computations on local clusters and the teragrid. Consequently, these tools are freely accessible and the dAFM simulations are run using standard web-based browsers without requiring additional software. A wide range of issues in dAFM ranging from optimal probe choice, probe stability, and tip-sample interaction forces, power dissipation, to material property extraction and scanning dynamics over hetereogeneous samples can be addressed.     

Wedged multilayer Laue lens

A multilayer Laue lens (MLL) is an x-ray focusing optic fabricated from a multilayer structure consisting of thousands of layers of two different materials produced by thin-film deposition. The sequence of layer thicknesses is controlled to satisfy the Fresnel zone plate law and the multilayer is sectioned to form the optic. An improved MLL geometry can be created by growing each layer with an in-plane thickness gradient to form a wedge, so that every interface makes the correct angle with the incident beam for symmetric Bragg diffraction. The ultimate hard x-ray focusing performance of a wedged MLL has been predicted to be significantly better than that of a nonwedged MLL, giving subnanometer resolution with high efficiency. Here, we describe a method to deposit the multilayer structure needed for an ideal wedged MLL and report our initial deposition results to produce these structures.     

基于X射线光谱仪分析环锭纺与集聚纺纱线织物丝光后的结晶度研究

在相同的纤维混合与工艺参数下分别制得环锭纺与集聚纺纱线织物,并在不同温度、氢氧化钠质量分数、浸渍时间及织物弹性伸长率条件下进行丝光处理。采用Mat-Lab计算分析软件对织物试样的X射线光谱进行分析,得到丝光作用的最佳条件。     

接触斑点对蜗轮副承载能力的影响

根据现有的技术发展水平,只有当蜗轮副的齿面完全啮合,才能评估其抗点蚀能力。但实际上,在蜗轮与蜗杆初始啮合时,它们只有一个较小的啮合斑点。由于时间和经费的关系,通过长时间轻载跑合使其达到完全啮合一般不太可能。在初期,由于接触面较小,齿部的接触应力会很大,有可能会在啮合处的表面产生一条微观裂纹,随后裂纹继续发展使材料从蜗轮上剥落,从而形成点蚀。较小的啮合斑点与点蚀的关系迄今还没有被系统的分析与研究,因此蜗轮轮齿也不能很好的进行优化。通过理论和实践相结合,提一种新的、可适用于不同尺寸、不同接触斑点位置以及齿形的计算方法,以弥补这一空白领域。     

Oerlikon Textile Components:牵伸能力

全球65%的环锭纺纱机上安装的摇架都是Texparts PK或者以Texparts PK为原理。毫无疑问,无论对粗纱机,还是细纱机;短纤纺纱,还是长纤纺纱,欧瑞康的短纤纱牵伸系统都是无与伦比的。     

Some natural flavonoids are competitive inhibitors of Caspase-1, -3 and -7 despite their cellular toxicity

A common feature of both apoptosis and inflammation is the activation of caspases. Caspases are aspartate-directed cysteine proteases that have numerous cellular targets. It has been discovered that several flavonoids are inhibitors of caspases. Flavonoids are members of a family of polyphenolic compounds from plants that have many biological properties, one of which is the ability to induce cell death. Some flavonoids are selective inhibitors of particular caspases. Since some of the inhibitory flavonoids are nevertheless cytotoxic, these results suggest that flavonoid-induced cell death may be occurring through a non-classical apoptosis pathway that is not dependent on caspase activity.     

高效率的机器人同事

添加剂生产中的托板堆放机器人系统 Steuler－KCH公司投资购置了一台Koch公司生产的托板堆放机器人系统，用于将不同添加剂产品向托板的堆放工作。它的工作效率非常高、大大地减轻了工人的劳动强度。同时，添加剂企业也在这一工序中实现了无人操作，极大地提高了企业的经济效益。     

肥皂性能的评定方法(一)

研究了全球肥皂厂家或研发实验室采用的评定方法,这些评定的目的是为了确保其满足生产标准,并最终保证消费者对他们购买到的肥皂产品感到满意。一般来说,评定方法包括分析化学检测(评定原材料和成品)、材料学法(评定产品结构)以及消费者可见属性的直接测试(例如泡沫、湿皂触感和磨损率)。这些检测可在实验室中进行或通过消费者评估进行。     

亚洲主要国家和中东地区的牵伸变形纱市场(二)

(上接本刊2012年第1期第7页)8印度——另一个"中国"?印度市场相当特别,且与其他国家不同,在经济上被称为是中国潜在的对手。印度作为世界上最大的民主国家,在DTY机器投资上似乎相当封闭。近年来政治上的努力正使得贸易自由化。减少贸易保护,事实上也就有利于机器     

Use of the radiofrequency-intermodulation distortion technique to investigate intrinsic nonlinearity at the electrode-electrolyte interface

We report on investigations of nonlinear radiofrequency responses of electrolytes with Na(+) and Cl(-) ions placed within gold electrodes of a capacitor. The sample was part of a frequency-adjustable inductance-capacitance-resistance (LCR) parallel resonant circuit, and measurements were carried out using the two frequencies intermodulation distortion technique. We employed double layer model to analyze the observed nonlinearities and their dependence on ionic concentration. Electrode-electrolyte interface polarization was found to be a predominant cause of this intrinsic nonlinearity and to be dependent on electrolytic ion concentration. We also measured and calculated coefficients of resistive and capacitive components of the observed nonlinearity.