超临界流体技术与超细粉体制备

综述了超临界流体应用于制备超细粉体的研究现状、主要研究成果和应用前景。介绍了超临界溶液快速膨胀(RESS)法,超临界流体抗溶剂(GAS)法,超临界气体抗溶剂沉淀(PCA)法,超临界逆向结晶(SRC)法,超临界流体渗透(SFI)技术,超临界干燥(SCFD)法和超临界流体化学反应法等,近年来开发的一些新方法和新工艺。分析了这些新工艺新方法的原理、特点、技术上的可行性、应用前景、目前达到的水平与存在的问题,以及今后的发展所需要解决的关键问题等。     

聚丙烯纤维的超临界流体染色

以超临界二氧化碳为介质研究了分散染料在聚丙烯及混纺织物上的染色能力．结果表明,选用合适的分散染料可使织物在较短时间内染色,而且产品颜色十分均匀．在16～26MPa和80～120℃范围内,染料在织物上的着色量较高且随温度和压力变化不大．     

超临界流体萃取天然药物的研究现状及发展趋势

综述近年来迅速发展起来的超临界萃取技术在天然药物提取中的研究现状，并对其今后的发展方向和趋势进行分析和讨论     

超临界流体干燥法制备炭气凝胶

以间苯二酚和甲醛为原料, Ca(OH)2为催化剂,经溶胶—凝胶过程得水凝胶 ;以超临界 CO2干燥水凝胶,得到网络间充满气体的固态材料气凝胶,再经高温热解得炭气凝胶。 TEM表征结果显示：气凝胶和炭气凝胶均具有规则的纳米网络结构,网络节点粒径约 10 nm,典型网络孔径小于 50 nm。     

KINETICS OF SUPERCRITICAL FLUID EXTRACTION OF ETHANOL FROM AQUEOUS SOLUTION

A 1.3 dm³ high-pressure vessel was used to extract ethanol from aqueous solution of 10 wt% using supercritical carbon dioxide as a solvent. Experiments were carried out in a semibatch mode. A mathematical model based on the two-film theory was derived for estimating the over all mass transfer coefficient. The effects of operating variables, including pressure, CO₂ superficial velocity, and agitation rate, on the mass transfer coefficient were investigated. In general, the mass transfer coefficient increased with increasing pressure, CO₂ superficial velocity, and agitation rate. The concentration of ethanol recovered in the collector after 180 minutes reached 50 wt%, starting with a feed of 10 wt% ethanol.     

CONTROLLED GROWTH OF COPPER NANOPARTICLES AND NANORODS IN THE CHANNELS OF SBA-15 BY SUPERCRITICAL FLUID DEPOSITION

Copper nanoparticles and nanorods were prepared in the one-dimensional channels of SBA-15 supported by a modified supercritical fluid deposition (SCFD) method. In this approach, cheap and widely available copper nitrate, which is insoluble in supercritical CO₂ (scCO₂), was used as the copper source and ethanol as the co-solvent, thus avoiding the employment of expensive and less available scCO₂-soluble precursors. The deposition was carried out at the pressure of 21–25 MPa and temperature of 50°C, followed by calcinations at 500°C and H₂ reduction at 500°C. The results showed that highly dispersed Cu nanoparticles or nanorods were obtained controllably just by varying the deposition time, as characterized by transmission electron microscopy (TEM) and X-ray diffraction (XRD). On the other hand, when Cu(acac)₂ was used as the precursor and without any co-solvent, only nanoparticles were formed in the channels of SBA-15 no matter how long the deposition time.     

多孔介质中流体流动的格子气自动机模拟

介绍了 13-Bit正六边形多速格子气自动机模型的特点 ,讨论了多孔介质流体流动的格子气自动机模型的渗透率等参量算方法 ,应用该模型对计算机产生的多孔介质几何构型和焦炭多孔介质中的流体流动进行了模拟 ,其结果既可以给出多孔介质中的流动细节 ,也可统计得到表征多孔介质宏观流动特征的物理参量 .初步研究表明 :格子气自动机模型可用于模拟复杂边界条件下多孔介质的流体流动     

AN EXPERIMENTAL STUDY OF THE PRESSURE DROP IN FLUID FLOWS THROUGH WIRE GAUZES

Catalytic wire gauzes have been used for many years for ammonia oxidation. The flow and transfer properties of stacked gauzes, however, have not been sufficiently examined in the literature. This study presents an experimental program designed to characterize the pressure drops observed across stacked woven and knitted wire gauzes. This work generated an extensive database of measurements and reveals that each gauze requires its own correlation equation. Furthermore, previously published general models were not able to describe all four cases with high accuracy. After surveying the literature, we present some modifications to the models based on our collected experimental results.     

超临界流体色谱法制备EPA-EE和DHA-EE

以二氧化碳作流动相,C18柱为固定相,用超临界流体色谱法制备二十碳五烯酸乙酯(EPA-EE)和二十二碳六烯酸乙酯(DHA-EE).考察了流速、温度、压力、上载量以及进样浓度对制备分离的影响.结果表明,在实验范围内,流速对分离效果影响不大.对于5-C18,250mm×4.6mm色谱柱,其最适制备条件是柱前压12MPa,温度55℃,通常流速下的压降约为1MPa,鱼油的最大上载量大于20μl.而对于8-C18,250mm×10mm色谱柱,其相应的最适制备条件是柱前压11MPa,温度55℃,通常流速下的压降约为0.5MPa,鱼油的最大上载量约为100μl.实验表明,鱼油无需溶解于其他溶剂而可直接进样.     

中高压玻璃钢管道在油田上的应用

本文概述了国外石油工业对中，高压玻璃钢管道的应用，介绍了我国首次进行的高压玻璃钢管道示范工程的应用情况。     

THEORY FOR STEP AND PULSE METHOD OF SUPERCRITICAL FLUID CHROMATOGRAPHY

1 INTRODUCTIONSupercritical fluid chromatography(SFC),employing supercritical fluid as mobilephase,originated in the 1960's [1-4].Since 1980's extensive research work has beenperformed on SFC,chiefly for analytical purposes [5,6].SFC was then adopted for thedetermination of thermodynamic properties such as partial molar volume,and partialmolar enthalpy of solutes in both mobile phase and stationary phase and the solutedistribution coefficient between two phases [7- 11].Partial molar properties can be de-     

PURIFICATION OF BILIRUBIN AND MICRO-PARTICLE FORMATION WITH SUPERCRITICAL FLUID ANTI-SOLVENT PRECIPITATION

1 INTRODUCTIONA supercritical fluid is one existing at temperatures and pressures above its criticalpoint values(T_c,p_c) [1].Supercritical fluid has unconventional thermophysical prop-erties,exhibiting higher density,greater compressibility,lower viscosity between the gasand liquid extremes.Its solute binary diffusion coefficient is considerably higher thanthat in liquids[2-4].Supercritical fluid extraction(SFE)has been suggested as a viablealternative to other separation technologies.     

EPA和DHA在超临界流体色谱柱中的传质动力学

用超临界流体色谱 (SFC)法研究了EPA和DHA在C18上的吸附和传质性能 .建立了色谱动力学模型并获得了模型参数 ,较好地拟合了实验流出曲线 .结果表明吸附平衡、轴向弥散、流体相传质和颗粒内有效扩散都是影响SFC分离EPA和DHA的重要因素     

EXPERIMENTAL AND NUMERICAL STUDIES OF HEAT TRANSFER THROUGH CONTACT AREAS OF HIGH ELLIPTICITY

This paper describes experimental and numerical studies of heat transfer between surfaces in contact over a highly elliptical area in the presence of a gas or in vacuum. Measurements of the steady-state thermal resistance of an elliptical contact (with a length/width ratio of 16, as predicted by Hertz's theory) formed between cylindrical steel contacting surfaces with widely different radii of curvature (76 cm. vs. 0.95 cm.) are reported and compared to numerical results obtained with a 3-D finite-difference model formulated in the ellipsoidal coordinate system. Very good agreement between experimental and numerical results is obtained. Experimental results are given for contacts with smooth and rough surfaces.     

船用新型复合高压气瓶设计与试验研究

利用10mm碳纤维增强复合材料环缠加强现役钢质气瓶,实现了船用新型复合高压气瓶的研制,并参照相关标准开展了水压、爆破、气密、疲劳等试验研究。结果表明,复合材料较好地分担了气瓶环向应力,爆破压力达到125MPa,经0~40MPa、12000次填充疲劳试验不发生破坏。试验表明复合气瓶设计合理,安全可靠性高,是实现船用新型高压气瓶研制的较好技术途径。     

高压电晕与臭氧协同处理间二氯苯废水的研究

本文的目的是要利用高压电晕与臭氧的协同作用处理难降解有毒有机废水，为此设计了高压电晕和臭氧协同处理废水的实验装置。实验表明：当废水呈酸性或碱性时处理效果要好于中性，废水初始pH=6，电压为30kV，频率为80Hz时，间二氯苯的处理效率达到88．2％；TOC降解41．3％。二者协同处理间二氯苯的效果要好于两种方法的单独使用。     

高温高压煤(烟)气的除尘技术分析

分析了ＩＧＣＣ和ＰＦＢＣ中应用的高温高压煤气和烟气尘粒含量,总结了燃气轮机透平保护标准和环保要求,对较适合的除尘技术进行了综合分析比较,并分析了各除尘技术存在的问题,认为刚性陶瓷过滤器具有广泛的应用前景。     

FLOW OF NEWTONIAN FLUIDS THROUGH SINUSOID ALLY CONSTRICTED TUBES. NUMERICAL AND EXPERIMENTAL RESULTS

Numerical and experimental predictions of pressure drops in the flow of Newtonian fluids through sinusoidally constricted tubes (SCT) are carried out. The numerical evaluations analyzed in this work are obtained from the following methods: Geometric Iteration (GJM), Geometric Iteration with First and Second Upwinds (GIM1, GIM2), Successive Over Relaxation by Line (SORBLM), Global Galerkin Spectral Method (GGSM), Collocation (CM) and Dufort-Frankel (DFM). The GIM1, GIM2 and SORBLM are applied to SCT and explained in this work. The other methods have been previously reported in the literature with the same purpose. Experiments are accomplished for constrictions of approximately 40,60 and 80% of the average tube diameter and results compare well with numerical predictions of the steady flow. It is concluded that special attention should be given to evaluations of the friction factor ƒ for Reynolds numbers Re between the onsets of flow separation and turbulence due to flow instability. Finally, the SCT as a model for porous media (PM) is discussed.     

加压下规整填料塔内气液两相流返混的实验研究:气相返混系数

规整填料因具有生产能力大、分离效率高、压降低、操作弹性大、持液量低等诸多优点 ,目前已被广泛应用于精馏、吸收及萃取等多种化工单元操作中 .通常只在常压或减压条件下操作 ,而在高压或大液相负荷下 ,因流体物性的变化及流动状态的改变 ,使塔内产生严重的返混 ,塔效率显著降低 .因此 ,研究加压下规整填料塔内流体的流动状态具有重要意义 .对于加压下填料塔内气相返混的研究 ,中国台湾的ＴａｎＣｈｕｎｇ -Ｓｕｎｇ[1] 在低实验气速 (0 .0 0 2～ 0 .1ｃｍ·ｓ- 1)下做过初步的研究 ,其实验填料为散堆填料 .Ｋｕｒｔｚ[2 ] 在这方面的研究…     

煤气CO和H2高电压放电反应机理研究

本文研究了ＣＯ和Ｈ_２的高电压放电反应机理，发现ＣＯ和Ｈ_２的放电化学反应是自由基反应，在高电压放电条件下，电子与ＣＯ和Ｈ_２分子碰撞激发生成自由基，发生化学反应；在低输入电压范围内，电场加速低能电子成为高能电子的过程为反应控制步骤。