水中"一锅"合成7,7-二甲基-4-(3-氯苯基)-5-氧代-3,4,5,6,7,8-六氢香豆素的洁净方法

研究了四丁基溴化铵(TBAB)催化下的水介质中,3-氯苯甲醛、丙二酸亚异丙酯和5,5-二甲基-1,3-环己二酮三组分缩合,一步合成系列7,7-二甲基-4-(3-氯苯基)-5-氧代-3,4,5,6,7,8-六氢香豆素。产物的结构经IR和1HNMR进行了表征确证。该方法具有反应条件温和、操作简便、环境友好的优点。     

连续介质模型在边坡渗流分析及疏干工程中的应用

针对露天矿山高边坡地下水渗流场的特点，通过对等效连续介质渗流运动方程中水压力传导系数的剖析和现场疏于工程实践总结，提出了有实用价值的边坡水压流干工程设计方法。     

聚酯装置热媒系统串级使用节能改造

现有部分聚酯车间设计和建设时间较早,装置能耗较高,为了节能降耗,对现有热媒系统进行改造,一是将装置高温回油梯级使用到低温系统;二是改造部分热媒系统为串级使用,停开或降低热媒泵电耗。经过以上一系列改造和优化,有效提高了热能使用效率,减少了装置耗电,从而实现了热媒系统的节能降耗。     

重介洗煤密度自控系统研究

目的：本文介绍了PLC在洗煤厂的介质密度控制中的应用,针对介质密度变化规律性不强,大滞后等特点作出调整。方法：采用VB编程语言结合专家算法的方针,提出了一个解决方案,提高了控制密度精度。结果：使物料浓度配比更加合理,趋势变化更容易让现场人员接受。结论：提高了产煤精度及生产效率,节约了能源的同时为洗煤厂创造更大的经济回报。     

公共制造云服务平台架构及其支撑技术研究

为了能使量大面广的中小企业充分享受云制造的益处, 分析了公共制造云的运行原理, 搭建了一个面向中小企业的公共制造云服务平台架构, 并给出了其形式化描述。对平台所涉及的关键支撑技术如云制造资源管理、协同设计及QoS管理进行分析, 提出了基于多级递阶控制结构的云制造资源管理与监控模型, 以及在云制造基础设施之上构建了支持复杂产品设计、面向服务的虚拟协同设计环境。最后通过公共制造云服务平台运作模型说明了平台的应用性和示范性。     

液相合成纳米氧化锌及其光催化性能探讨

以硝酸锌和氢氧化钠为原料,分别以水和醇作为溶剂,采用液相直接沉淀法合成纳米氧化锌。在以水为反应溶剂条件下,研究了反应时间、反应温度、反应物浓度和反应物配比对纳米氧化锌中位径和形貌的影响,得到制备较小中位径及合适长径比纳米氧化锌的最优反应条件,即:反应时间为3 h、反应温度为70 ℃、锌离子浓度为0.5 mol/L、锌离子与氢氧根浓度比为1:2。在上述最优反应条件下,研究了不同醇溶剂对纳米氧化锌中位径、形貌及其光催化性能的影响。研究发现,随着溶剂碳链长度的增长,纳米氧化锌中位径呈现上下波动,无明显变化规律,形貌由球状向柱状发展,光催化性能总体不断减弱。     

Liquid Radial Dispersion in Liquid-solid Circulating Fluidized Beds with Viscous Liquid Medium

Liquid dispersion in the radial direction was investigated in the riser of a viscous liquid-solid fluidized bed 0.102 m in diameter and 3.5 m in height. Pressure fluctuations in the riser were also measured and analyzed to examine the behavior of fluidized particles. Effects of liquid velocity (0.15-0.45 m/s), solid circulation rate (2-8 kg/m²s), particle size (1-3 mm), and liquid viscosity (0.96-38 mPas) on pressure fluctuations and the liquid radial dispersion coefficient were determined. The infinite space model was employed to obtain the radial dispersion coefficient from the radial concentration profiles of the tracer. The pressure fluctuations were analyzed by means of autocorrelation coefficient as well as power spectral density function. The dominant frequency obtained from the autocorrelation coefficient or power spectral density function of pressure fluctuations decreases with increasing liquid viscosity or liquid velocity, but it increases with increasing particle size. The liquid radial dispersion coefficient decreases with increasing liquid velocity or viscosity, but it increases as the solid circulation rate or particle size increases. The liquid radial dispersion coefficient is related closely to the resultant behavior of fluidized particles. The radial dispersion coefficient has been well correlated with operating variables in terms of dimensionless groups.     

一种简单便携的存储介质信息检测及备份装置研究

随着信息时代的飞速发展,数据信息在生活中的作用越来越显重要,数据恢复在社会生活中的应用越来越广,这便需要对存储介质的信息进行必要的检测和备份。虽然一些常见的软件可以通过PC端实现检测和备份功能,但也就是针对常见USB设备和一些专业性比较强的硬盘,不方便备份且不易携带,因此能提供一种兼容各种存储介质,并且方便使用、易于携带且不依赖于电脑就能实现检测和备份的设备非常重要。本文阐述了一种简单便携的存储介质信息检测及备份装置的研究设计．．     

采用两种中间介质的工业园区厂际余热集成

发挥园区集群效应，借助中间介质回路将工业园区中各单厂内的余热于厂际间进一步回收利用，能够显著提高园区整体能源效率。其中，中间介质回路的设置与介质的选择将关系到整个余热回收系统的最优设计与节能效果。因此，不同于目前研究仅采用一种中间介质的集成策略，同时选用热水和导热油为介质开展厂际余热集成研究。提出耦合介质与厂内流股换热及介质流股在厂际间分配的换热器网络超结构，以年度总费用最小为目标建立MINLP热集成数学模型，优化获得包含介质回路结构与厂内换热器网络结构等内容的园区余热集成结果。最后，在一个包含3个厂的厂际余热集成案例中，分别研究了单种介质单回路、单种介质双回路及双种介质双回路3种情况，通过对比验证了所提方法的有效性。     

Electroreduction of dioxygen (ORR) in alkaline medium on Ag/C and Pt/C nanostructured catalysts—effect of the presence of methanol

Ag/C catalysts with different loading were prepared using a colloidal route to obtain well dispersed catalysts on carbon, with a particle size close to 15 nm. An amount of 20 wt.% Ag on carbon was found to be the best loading in terms of current density and mass activity. The 20 wt.% Ag/C catalyst was then studied and the kinetics towards ORR was determined and compared with that of a 20 wt.% Pt/C catalyst. The number of exchanged electrons for the ORR was found to be close to four with the rotating disk electrode (RDE) as well as with the rotating ring disc electrode (RRDE) techniques. From the RDE results, the Tafel slopes b, the diffusion limiting current density inside the catalytic film (j_l^film) and the exchange current density (j₀) were evaluated. The Tafel slopes b and diffusion limiting current densities inside the catalytic film (j_l^film) were found to be in the same order for both catalysts, whereas the exchange current density (j₀), which is a suitable estimation of the activity of the catalyst, was at least 10 times higher at the Pt/C catalyst than at the Ag/C catalyst. The behavior of both catalysts in methanol containing electrolyte was investigated and it was found that at a low methanol concentration, the Pt/C catalyst was quasi-tolerant to methanol. But, at a high methanol concentration, the ORR at a Pt/C was affected. However, the Pt/C catalyst showed in each case better activity towards ORR than the Ag/C catalyst, even if the latter one was less affected by the presence of methanol than the former one.