烧碱蒸发装置的改进

通过改进工艺流程，科学确定加热面积的配比，合理选择采盐泵等技术改进措施，提高了生产强度，满足了高气压的生产条件，延长了洗效周期，减少了设备的腐蚀，提高了成品碱的质量，满足了生产联二脲的要求并降低了汽耗和电耗，年可节约ll0万元。     

Molecular simulation of hydrogen adsorption in organic zeolite

The adsorption of molecular hydrogen on model zeolites has been simulated employing Grand Canonical Monte Carlo (GCMC) procedure. The effects of cation type, available volume, surface area, temperature, pressure and pre-adsorbed organics such as benzene on the hydrogen uptake are analyzed. The hydrogen adsorption can be affected mainly by the available volume and surface area per g-zeolite at the same temperature and pressure. Increase of temperature results in the decrease of sorption intensity and capacity. The adsorption capacity correlates well with the pressure with high linearity at room temperature. Adsorption is lowered by the pre-adsorbed benzene molecule. The orientation and the number of benzene molecule in zeolite affect the adsorption capacity. The organic zeolite with larger available volume shows larger adsorption capacity.     

Liquid-phase adsorption of dyes and phenols using pinewood-based activated carbons

Physical properties of activated carbons prepared from pinewood at different activation times (0.5, 1.5, 2.7, and 4.0 h) in steam at 900 °C were studied. The adsorption equilibria and kinetics of three dyes and three phenols (phenol, 3-chlorophenol, and o-cresol) from aqueous solutions on such carbons were then examined at 30 °C. The adsorption isotherms of phenols could be well fitted by the Freundlich equation, and those of dyes were adequately described by the Langmuir-Freundlich equation. The effect of microporosity of the carbons on adsorption capacity was explored. Four simplified kinetic models including pseudo-first-order equation, pseudo-second-order equation, intraparticle diffusion model, and the Elovich equation were selected to follow the adsorption processes. The adsorption of all six adsorbates could be best described by the Elovich equation. The kinetic parameters of this best-fit model were calculated and discussed.     

论局域网的安全防范

网络技术、通信技术和计算机技术的突飞猛进使得很多的企业单位、机关部门和学校搭建了属于自己的局域网.信息安全问题是局域网实际应用过程中最受关注的问题.本文阐述了局域网安全的内涵和意义,分析了目前局域网安全防范中存在的问题,并根据笔者的实际经验给出了有效增强局域网安全防范的相关建议.     

计算机局域网网络的安全现状与对策分析

在现代企业中,随着办公自动化进程的不断深入,计算机局域网得到了普遍的发展,在很大程度上提高了工作效率。但是局域网技术在为工作带来便利的同时,安全问题也是比较严重的。本文主要探究的是计算机局域网网络的安全现状,并提出了相应的对策和解决措施。     

一种基于网络应用特征串识别的局域网管理方案

鉴于网络应用的高速发展,局域网呈现出复杂化的趋势,为更好的完成局域网管理的工作,提出一种基于网络应用行为识别与统计分析的局域网管理方案。该方案以网络特征串识别网络应用行为为基础,以主动识别网络应用行为的方式,通过对网络应用的归类和统计分析实现对局域网网络的积极管理。该方案可以在局域网内有效实现对网络应用的主动监控,网络管理员可以自行设置网络管理方式,达到主动管理灵活监控的目标,优化局域网网络环境。     

动态法快速测定催化剂比表面

本文采用动态法原理测定催化剂的比表面，利用热导检测器测定催化剂微孔在液氮下的吸附及常温下的脱附面积。用外标法进行定量。该方法分析速度快．在l小时内同时测定3个样品的比表面。其准确度及精密度满足要求。     

Preparation of porous carbons from thermoplastic precursors and their performance for electric double layer capacitors

Porous carbons with high surface area were successfully prepared from thermoplastic precursors, such as poly(vinyl alcohol) (PVA), hydroxyl propyl cellulose and poly(ethylene terephthalate), by the carbonization of a mixture with MgO at 900 °C in an inert atmosphere. After carbonization the MgO was dissolved out using a diluted sulfuric acid and the carbons formed were isolated. The mixing of the PVA carbon precursor with the MgO precursors (reagent grade MgO, magnesium acetate or citrate) was done either in powder form or in an aqueous solution. The BET surface area of the carbons obtained via solution mixing could reach a very high value, such as 2000 m²/g, without any activation process. The pore structure of the resultant carbons was found to depend strongly on the mixing method; the carbons prepared via solution mixing were rich in mesopores, but those produced via powder mixing were rich in micropores. The size of mesopores was found to be almost the same as that of the MgO particles, suggesting a way of controlling the mesopore size in the resultant carbons. Measurement of capacitance was carried out in 1 mol/L H₂SO₄ electrolyte. The porous carbon with a BET surface area of 1900 m²/g prepared at 900 °C through solution mixing of Mg acetate with PVA showed a fairly high EDLC capacitance, about 250 F/g with a current density of 20 mA/g and 210 F/g with 1000 mA/g. The rate performance was closely related to the mesoporous surface area.     

On the importance of some surface and interface characteristics in the formation of the properties of adhesive joints

The importance of some relative surface characteristics which determines the strength of adhesive joints: specific surface of substrate , relative contact area β and specific contact area β in the adhesion interaction process were emphasised. Existing and potential methods of experimental evaluation of these characteristics were shortly analysed. The durability of the adhesive joints in water media significantly increases with growth of specific surface ^* of chemically treated substrate evaluated from the SEM micrographs. Specific surface calculated from the experimental data of hexane adsorption measurements for iron particles (particulate model of steel substrate) is more then ten times greater than respective ^* values. The relative contact area β of the Al₂O₃ particles (in wide range of ) with PE melt was in a roundabout way evaluated by experimental determination of the affect of on kinetic of peel strength formation of adhesive joints: Al₂O₃ filled PE-steel. The speculation was based on the ability of Al₂O₃ to adsorb low-molecular products of contact oxidation of PE which takes place in the process of formation of adhesive joints and determines their strength. The ability of sorption in its turn is proportional to efficient value of β. The availability of the Al₂O₃ surface was evaluated.