非低温法的稀有气体纯化技术概述

稀有气体广泛应用于工业生产中,如离子刻蚀、检漏等。但是它们在地球上的含量比较少,属于稀有资源,因此需要对它们进行纯化以循环再利用。首先介绍了不同气体纯化的原理,然后以实际生产中的不同稀有气体使用范围为例,说明纯化装置的设计方法和需要考虑的问题。为以后气体纯化装置的设计提供借鉴。     

Growing ordered arrays of vertically aligned copolymer nanowires for supercapacitors with high stability

Journal of Solid State Electrochemistry - In this report, we present a novel platform to study the formation of delicate ordered vertically aligned copolymer nanowires array with EDOT and Py as the...     

Optical pattern simulations for closed cylinders of liquid crystals

Abstract

Optical patterns for the polarizing microscope textures of closed cylinders of liquid crystals (CCLCs) are studied by the Jones vector formulation. The simulated director configuration diagram of a CCLC with normal orientation at the walls contains four kinds of stable director configurations. The resulting texture under some approximations depends only on phase shifts. The patterns are characterized by dark brushes that coincide with the directions of the crossed polarizers. Additionally, there are concentric circle fringes. For the ring defect structure, the centre region of the cylinder exhibits a black extinction. However, this is not distinguishable as between the hyperbolic and radial structures for both the point and the ring defect patterns. Comparing the observed patterns with the simulated ones, we find that the dark cross brushes and the centre black extinction of simulated patterns are similar to those that are observed. However, the concentric circle fringes of the observed pattern are not in accordance with the simulated pattern.     

Identification of metabolites in WZS‐miniature pig urine after oral administration of Danshen decoction by HPLC coupled with diode array detection with electrospray ionization tandem ion trap and time‐of‐flight mass spectrometry

Danshen (DS) is a widely used traditional Chinese medicine for treating cardiovascular and cerebrovascular diseases. A simple, rapid and sensitive method was developed for identification of the in vivo metabolites in urine of WZS‐miniature pigs after oral administration of DS decoction by HPLC coupled with diode array detection with electrospray ionization tandem ion trap and time‐of‐flight mass spectrometry. This method has been successfully applied to simultaneous identification of 50 compounds (including 11 new ones) in pig urine. In addition, one new compound, (3‐hydroxyphenyl) crylic acid glycine methyl ester (C1), along with eight known ones were first isolated by column chromatography and identified by spectroscopic means, including 1D/2DNMR and mass spectrometry, as reference substances. Ten phenolic compounds (protocatechuic aldehyde, protocatechuic acid, caffeic acid, danshensu, ferulic acid, isoferulic acid, rosmarinic acid and salvianolic acid A/B/D) were found to be the main absorbed original constituents of DS decoction, which underwent the metabolic reactions of glucuronidation, sulfation, methylation, hydrogenation and glycine conjugation in vivo. In conclusion, the developed method is applicable to the analysis and identification of constituents in biological matrices after administration of DS decoction. Copyright © 2012 John Wiley & Sons, Ltd.     

Effects of Cr and V impurities on cohesion properties of Pd/TiAl interfaces

First principles calculations reveal that for Pd/TiAl interfaces the substitution of interface Ti atoms with Cr or V atoms is energetically favorable with negative heat of formation, and could bring about a very small increase of interface bond strength, while the interstitial Cr and V atoms should be unfeasible with highly positive heat of formation and would increase the bond lengths of interface Pd–Al and Pd–Ti bonds. Calculations also demonstrate that both Cr and V would induce an increase of interface energy, suggesting that the impurity atoms of Cr or V should be reduced to a minimum level, in order to get a thermally stable Pd/TiAl interface with a longer lifetime. In addition, it is found that the substitution of V at the Pd/TiAl interfaces should be much easier than that of Cr, which is in good agreement with similar experimental observations in the literature.     

Editorial for Special Issue on Terahertz Technologies and Applications

Terahertz radiation,defined in the frequency range of 0.1-10 THz,has been exploited to demonstrate unique properties that do not apply to the adjacent domains of the electromagnetic waves,such as infrared and microwave.Recent advances in terahertz science and technology hold promise for a wide variety of essential applications,particularly in spectroscopy,sensing,imaging,non-destructive detections,and communications.This focus issue is comprised of invited and contributed original     

不同尺寸的NdFeB稀土永磁体热退磁行为研究

针对不同类型及不同尺寸的两类NdFeB永磁体分别研究了它们随温度变化的热退磁行为。采用样品的整体剩余磁通来表征热退磁过程中磁体性能的变化。结果表明,Pc较小的永磁体温度稳定性较差,随温度的升高,样品的剩余磁通迅速衰减;Pc<<0.1的普通型永磁体,温度为100℃时样品的剩余磁通损失超过60%。高矫顽力型永磁体比普通型磁体具有更优越的温度稳定性和高温性能。温度升高主要导致磁体矫顽力降低,140℃时普通型磁体的矫顽力降低约80%,而高矫顽力型磁体的矫顽力只降低了约20%。