半干面加工工艺论述

通过对半干面特性和加工现状分析,阐述2种国内半干面加工工艺及其优缺点,以及半干面加工机械化、自动化现状及存在问题,为半干面产业创新发展提供支撑.     

高铬抗磨铸铁生产技术相关的若干原理及实践问题辨析

高铬白口抗磨铸铁具有优异的抗磨特性,在众多行业的装备中广泛地发挥着重要作用,同时也为铸造生产商提供了一块巨大的市场份额。然而,尽管我国生产高铬铸铁已有几十年的历史,至今仍有不少企业在拟定或调整其成分及生产工艺方面尚存在一些困惑,其结果是,要么相关性能指标偏低,要么用户经常反馈一些存在的质量问题,甚至面临丧失新、老用户的尴尬。文中较全面地总结了主要成分对高铬铸铁组织、性能的影响规律和作用机制,以及成分选择的准则和范围,并从脱稳处理和亚临界处理的原理出发,以多个角度对高铬铸铁热处理工艺原则和技术实践关键问题进行了剖析,期望对相关企业技术人员和决策者有所借鉴。     

油田与农田的对接—访全国政协常委、民建中央副主席路明

路副主席，您在今年全国政协会议的发言中提出，要实施石油替代战略，发展替代石油的农业，得到各方面的广泛关注。请问，您作为农业专家，把石油与粮食这两件事联系在一起，是出于何种考虑呢？     

True64 UNIX操作系统下串口通信程序开发

HP公司的A1pha DS系列小型机在自检时通过串口输出丰富的自检信息，本程序在Tru64 UNIX 5．1B操作系统下用C语言开发，用于接收Alpha DS系列小型机的串口输出信息，并可以通过串口对机器进行操作，是一个非常实用的程序，为Alpha DS系列小型机的故障定位和修复提供十分有效的帮助。     

PB3—6GAZ型高压真空配电装置的问题与改进

分析了ＰＢ３－６ＧＡＺ型高压真空配电装置存在问题，介绍了改进方法和选择脱扣器原则。     

Characteristics of cellulosic amine-crosslinked copolymer and its sorption properties for Cr(VI) from aqueous solutions

A new cellulosic amine-crosslinked copolymer was prepared after the amination reaction with cotton stalk peel (CSP). The physicochemical characteristics of amine-crosslinked cotton stalk peel (AC-CSP) and raw CSP were determined after the surface analysis (including specific surface area, micropore volume and SEM), zeta potential analysis and spectrum analysis (FTIR and Raman spectrum). The sorption properties of AC-CSP for Cr(VI) were evaluated in the static, column sorption and desorption tests. The surface characteristics indicated the absence of porous adsorption in the potential Cr(VI) sorption mechanism. Zeta potential and spectrum analysis of AC-CSP illustrated the involvement of amine groups in the Cr(VI) sorption process. The sorption capacity of AC-CSP for Cr(VI) was 129.0mg/g as comparison with 14.8 mg/g of raw CSP. Flow rate and influent Cr(VI) concentration were demonstrated as two influencial factors in the column sorption tests. NaCl was used as the eluent, and the desorption efficiencies during three successive cycles were 75.9%, 69.8% and 64.3%, respectively. In addition, the results of the static, column sorption and desorption tests illustrated the complicated interactions between Cr(VI) and AC-CSP including complexation and ion exchange mechanisms.     

Amazing ageing property and in situ comparative study of field emission from tungsten oxide nanowires

In this work, needle-shaping of tungsten oxide nanowires occurred during field emission characterization. Compared with nanowires with a flat apex, needle-shaped emitters showed a lower threshold field of 11.9 V μm(-1) for 1 mA cm(-2) and a higher emission current of 1120 μA at 16.2 V μm(-1). Most notably, the measured ageing current dramatically increased by more than four times until it slightly decreased, tending towards stability. In addition, the samples showed striking difference in their nonlinear Fowler-Nordheim plot before and after ageing tests. Selected area diffraction and transmission electron microscope characterizations were used to further study these amazing results.     

Facile synthesis of near-monodisperse Ag@Ni core-shell nanoparticles and their application for catalytic generation of hydrogen

Magnetically recyclable Ag-Ni core-shell nanoparticles have been fabricated via a simple one-pot synthetic route using oleylamine both as solvent and reducing agent and triphenylphosphine as a surfactant. As characterized by transmission electron microscopy (TEM), the as-synthesized Ag-Ni core-shell nanoparticles exhibit a very narrow size distribution with a typical size of 14.9 ± 1.2 nm and a tunable shell thickness. UV-vis absorption spectroscopy study shows that the formation of a Ni shell on Ag core can damp the surface plasmon resonance (SPR) of the Ag core and lead to a red-shifted SPR absorption peak. Magnetic measurement indicates that all the as-synthesized Ag-Ni core-shell nanoparticles are superparamagnetic at room temperature, and their blocking temperatures can be controlled by modulating the shell thickness. The as-synthesized Ag-Ni core-shell nanoparticles exhibit excellent catalytic properties for the generation of H(2) from dehydrogenation of sodium borohydride in aqueous solutions. The hydrogen generation rate of Ag-Ni core-shell nanoparticles is found to be much higher than that of Ag and Ni nanoparticles of a similar size, and the calculated activation energy for hydrogen generation is lower than that of many bimetallic catalysts. The strategy employed here can also be extended to other noble-magnetic metal systems.     

High Temperature Tensile Property and Fracture Behavior of Directionally Solidified Fe-Al-Ta Eutectic Composites

Fe-Al-Ta eutectic composites with solidification rates of 6,20,30,80 and 200μm/s were obtained by a modified Bridgman directional solidification technique and alloying.Moreover,tensile property and fracture behavior of Fe-Al-Ta eutectic composites were studied at 600 ℃.The relationship between mechanical property and microstructure at high temperature was studied.Microstructure of Fe-Al-Ta eutectic is composed of Fe₂Ta (Al) Laves phase and Fe (Al,Ta) matrix phase.In addition,the tensi...