电力负荷削峰减载系统在珠钢电炉的应用

借助现场采集装置,在计算机上获取每一分钟的冶炼工艺电能需求量,显示当前15分钟时段已发生的电耗量,调整用户设定,实现需量自动刷新、报警和专家分析推荐后续用量;实现平稳用电并减少对电网冲击,同时降低电能最大需用量以减少成本。     

Local residence time,residence revolution,and residence volume distributions in twin‐screw extruders

This work was aimed at studying the overall, partial, and local residence time distributions (RTD); overall, partial and local residence revolution distributions (RRD) and overall, partial and local residence volume distributions (RVD) in a co‐rotating twin screw extruder, on the one hand; and establishing the relationships among them, on the other hand. Emphasis was placed on the effects of the type and geometry of mixing elements (a gear block and various types of kneading elements differing in staggering angle) and process parameters on the RTD, RRD and RVD. The overall and partial RTD were directly measured in‐line during the extrusion process and the local ones were calculated by deconvolution based on a statistical theory. The local RTD allowed comparing the mixing performance of mixing elements. Also it was confirmed both experimentally and theoretically that specific throughput, defined as a ratio of throughput (Q) over screw speed (N), controlled all the above three types of residence distributions, be they local, partial or overall. The RRD and RVD do not provide more information on an extrusion process than the corresponding RTD. Rather they are different ways of representing the same phenomena. POLYM. ENG. SCI., 48:19–28, 2008. © 2007 Society of Plastics Engineers     

基于Lab VIEW的小型汽油机磁电机点火提前角的测量

本文介绍了磁电机点火系统的点火提前角测量原理。对点火系统的点火信号和触发信号进行采集、调理，再用单片机进行处理，最后用LabVIEW进行点火提前角数据存储和显示。     

HSDPA部署策略及覆盖、容量规划

本文介绍了HSDPA的发展背景,针对HSDPA的主要技术特点,依据市场发展规划、用户需求等方面对HSDPA部署进行探讨,并对HSDPA的覆盖与容量方面进行规划分析.     

A Nonvolatile Organic Memory Device Using ITO Surfaces Modified by Ag‐Nanodots

We report on a single‐layer organic memory device made of poly(N‐vinylcarbazole) embedded between an Al electrode and ITO modified with Ag nanodots (Ag‐NDs). Devices exhibit high ON/OFF switching ratios of 10⁴. This level of performance could be achieved by modifying the ITO electrodes with some Ag‐NDs that act as trapping sites, reducing the current in the OFF state. Temperature dependence of the electrical characteristics suggest that the current of the low‐resistance state can be attributed to Schottky charge tunnelling through low‐resistance pathways of Al particles in the polymer layer and that the high‐resistance state can be controlled by charge trapping by the Al particles and Ag‐NDs.     

Effect of surfactants and liquid hydrocarbons on gas hydrate formation rate and storage capacity

Hydrate formation rate plays an important role in making hydrates for the storage and transport of natural gas. Micellar surfactant solutions were found to increase gas hydrate formation rate and storage capacity. With the presence of surfactant, hydrate could form quickly in a quiescent system and the energy costs of hydrate formation reduced. Surfactants (an anionic surfactant, a non‐ionic surfactant and their mixtures) and liquid hydrocarbons (cyclopentane and methylcyclohexane) were used to improve hydrate formation. The experiments of hydrate formation were carried out in the pressure range 3.69–6.82 MPa and the temperature range 274.05–277.55 K. The experimental pressures were kept constant during hydrate formation in each experimental run. The effect of anionic surfactant (sodium dodecyl sulphate (SDS)) on natural gas storage in hydrates is more pronounced compared to a non‐ionic surfactant (dodecyl polysaccharide glycoside (DPG)). The induction time of hydrate formation was reduced with the presence of cyclopentane (CP). Cyclopentane and methylcyclohexane (MCH) could increase hydrate formation rate, but reduced hydrate storage capacity The higher methylcyclohexane concentration, the lower the hydrate storage capacity. Copyright © 2003 John Wiley & Sons, Ltd.     

Complementary effects of solid lubricants in the automotive brake lining

An experimental investigation was carried out to examine the tribological behavior of NAO (non-asbestos organic) type brake linings containing different volume ratios of graphite and antimony trisulfide (Sb₂S₃). A scale dynamometer was used for friction tests and particular emphases were given to the effect of applied pressure, sliding speed, and temperature on the coefficient of friction according to the relative amounts of the two solid lubricants. Results showed that the brake linings with both solid lubricants exhibited better friction stability and less speed sensitivity than the friction materials containing a single solid lubricant. In particular, the brake lining containing higher concentrations of graphite showed better fade resistance than others during high-temperature friction test.     

储层压力与天然气分布关系——以鄂北塔巴庙地区上古生界储层为例

通过分析塔巴庙地区储层压力的分布特征，建立了研究区泥岩压实曲线，并对影响和控制该区储层压力的主要因素和机理进行了探讨，对“欠压实”剩余压力、生气增压、抬升引起的降压进行了定量计算。分析结果表明，晚三叠-早白垩世末“欠压实”作用和晚侏罗-早白垩世末烃源岩大量生烃作用使塔巴庙地区上古生界形成异常高压；晚白垩系构造抬升降压，使得现今储层为正常-低异常压力。同时证实了“欠压实”对天然气有压力封盖作用，天然气都分布在最大“欠压实”幅度以下的储层当中。烃源岩生气高峰为晚侏罗-早白垩世末，但天然气大规模运移是在晚白垩世，方向以沿过剩压力梯度降低较快的方向（太原-山西组至下石盒子组）垂向运移，通道主要为裂缝，运移的动力主要为异常高压。由于储层致密，聚集成藏能量有限，造成天然气充注不足、气水分异不好、含气饱和度低。     

A Study on NMR and GC/MS Spectra of the Isomers of Linear Hexyl Naphthalene

The GC/MS and NMR analysis of the reaction products of naphthalene with 1-bromohexane were reported. The products obtained were suggested to have six isomers of linear hexylnaphthalene and the structure of each isomer was determined by GC/MS and NMR spectra. For the first time, the unique chemical shift data were obtained. The content of each isomer calculated by ¹H NMR and ¹³C NMR spectra was consistent with that by GC/MS spectra, which confirmed the accuracy of NMR data.     

线性调制抗噪声性能的提高方法

本文主要是在线性解调系统中,利用信道中加性高斯白噪声正交分量(nc与Ns)两者正交性与其中之一(ns)经相移之后形成线性相关性使噪声本身消除噪声,以达到提高信噪比的目的,从而提高抗噪声性能.