氧化锆在电场下的相变

在２００－４００℃温度范围内，电场可以显著促进３％Ｙ２Ｏ３－ＺｒＯ２中四方相氧化锆向单斜相的转变，而且其等温动力学曲线呈抛物线规律，这说明在氧化四方相向单斜相的转变过程中存在着明显的扩散篚现象。另外，近阳极而的相变量明显高于阴极面的相变量，这说明该相变过程与氧空位或缺陷簇的迁移过程密切相关。     

高频电场处理水的试验研究

本文对利用高频电场处理水的防垢效果进行了试验，讨论了电场频率，强度，水中钙浓度，ｐＨ以及加热时间等因素对防垢效果的影响。根据试验结果，提出了设计参数，并对防垢机理进行了初步探讨。     

直流电弧电渣钢包炉电磁场速度场温度场的三维数值模拟

应用保角变换，采用贴体坐标，建立了非规范正交曲线坐标系的直流电弧电渣钢包炉钢液与两相流的电磁场、速度场、温度场的三维数学模型，用φω法进行了联立耦合数值计算，在生产过程中测量电磁场与温度场，预测与实测结果基本一致．     

解感生电场的格林函数法

感生电场的计算公式清楚的给出感生电场的方向和大小,用格林函数,容易得到此表达式。     

交变电场作用下煤吸附甲烷特性的研究

对交变电场作用下煤吸附／解吸甲烷特性进行了研究。结果表明：交变电场作用下：各煤样吸附甲烷的量仍很好地遵从Ｌａｎｇｍｕｉｒ方程,交变电场的作用减弱了煤的吸附能力和解吸能力,并且减缓了含甲烷煤的解吸过程,但对煤的饱和吸附量和最大解吸量影响不大。     

电场对超滤膜污染和去除性能影响的研究

研究了电场对超滤膜污染和去除性能的影响。结果表明,原水中的腐植酸在电场中发生电泳迁移,减少了向膜表面的移动,同时发生凝聚现象,沉积在膜表面形成疏松的滤饼层,有效的减缓了膜污染。经过与普通超滤膜过滤的平行试验比较得出,附加电场后对羟苯甲酮(BP-3)的去除率提高了70%～100%。同时发现,吸附是大孔径低压膜去除小分子BP-3的主要作用,水中腐植酸的存在对超滤去除BP-3有一定的促进作用。通过稀HCl、NaOH溶液浸泡和水力冲洗,可有效消除膜污染,使得膜过滤通量得到恢复。     

HEAT TRANSFER IN A THIN LIQUID FILM IN THE PRESENCE OF AN ELECTRIC FIELD

Heat transfer enhancement in an evaporating thin liquid film utilizing a electric field under isothermal interfacial condition is presented. A new mathematical model subjected to van der Waals attractive forces, capillary pressure, and an electric field is developed to describe the heat transfer enhancement in the evaporating thin liquid film. The effect of the electrostatic field on the curvature of the thin film, evaporative flux, pressure gradient distribution, heat flux, and heat transfer coefficient in the thin film is presented. The results show that applying an electric field can enhance heat transfer in a thin liquid film significantly. In addition, utilizing electric fields on the evaporating film will be a way to expand the extended meniscus region to attain high heat transfer coefficients and high rates of heat flux.     

HEAT TRANSFER IN A THIN LIQUID FILM IN THE PRESENCE OF AN ELECTRIC FIELD

Heat transfer enhancement in an evaporating thin liquid film utilizing a electric field under isothermal interfacial condition is presented. A new mathematical model subjected to van der Waals attractive forces, capillary pressure, and an electric field is developed to describe the heat transfer enhancement in the evaporating thin liquid film. The effect of the electrostatic field on the curvature of the thin film, evaporative flux, pressure gradient distribution, heat flux, and heat transfer coefficient in the thin film is presented. The results show that applying an electric field can enhance heat transfer in a thin liquid film significantly. In addition, utilizing electric fields on the evaporating film will be a way to expand the extended meniscus region to attain high heat transfer coefficients and high rates of heat flux.     

SOLID PHASE EXTRACTION FOR DETERMINING ORGANIC COMPOUNDS IN HIGH IONIC STRENGTH SOLUTIONS

ABSTRACT

Extraction techniques for semi-volatile organic compounds from caustic and high ionic strength solutions are presented. It is demonstrated that simple liquid-liquid extraction from a high ionic strength aqueous solution can allow inorganic ions to partition from the aqueous phase into the organic extraction phase. The ability of solid-phase extraction (SPE) adsorbents to separate organic target compounds from a sample, without significant carry-over of inorganic material, is compared to that of Liquid-liquid extraction. The most useful SPE media was a commercially available alumina substrate coated with a robust non-polar phase. Extractions of three compound classes, are presented: aromatic, alkyl hydrocarbons and alkyl phosphates. Extraction yields ranged from 42 to 97.6% (6-12% RSD). The range of yields for each chemical class was 7.5-79.9%, 14.3-68.3% and 91.1-97.6% for the aromatic, alkyl hydrocarbons and alkyl phosphate compounds respectively.     

交变电场下离子交换色谱分离过程

以牛血清白蛋白在阴离子交换剂DEAE -SepharoseFastFlow上的吸附和解吸过程为例 ,考察了交变电场下离子交换色谱过程的吸附和洗脱过程及其传质特性 .结果表明 :在本文实验条件下 ,交变电场电流强度的变化对离子交换吸附平衡无显著影响 ,而外加电场在介质孔内所产生的电渗流可加速待分离组分进出固相介质的传递过程 ,显著提高色谱填充床的动态吸附容量 ,改善洗脱峰的特性     

外加电场对弱导电工质管外沸腾传热强化的实验研究

针对化工过程和能源工程中常遇到的弱导电工质,通过施加一高压直流电场进行管外沸腾传热的强化实验,得出了外加电场电压、热流密度与沸腾换热系数及强化系数之间的规律.比较分析了工质不同组分对电流体动力学(EHD)强化效果的影响,并对外加电场的功耗进行了分析,为探索EHD强化沸腾换热的机理以及将其推广到工程应用中提供了一定依据.     

溶胀对膜萃取传质性能的影响

溶剂对膜的溶胀,使膜的物理结构发生变化,进而对膜萃取传质性能产生一定的影响。本文以３０％ＴＢＰ（煤油）－醋酸－水,正丁醇－醋酸－水和２０％７３０１（煤油）－醋酸－水为实验体系在聚砜和聚四氟乙烯微孔平板膜器中系统地了溶胀地膜萃取总传质系数的影响。结果表明,微孔膜发生溶胀后孔隙率发生明显的变化,其总传质系数有较大的下降。     

HIGH ELECTRIC FIELD DRYING OF JAPANESE RADISH

Japanese radish (Raphanus sativus L.) slices were dried under an alternating current (AC) high electric field (HEF) of 430 kV/m using a multiple point electrode and a grounded copper mesh. HEF with multipoint to a mesh electrode system could evaporate 87.5% of the total moisture from fresh radish slices on 7 h exposure. Oven-drying at 60°C and ambient air at 25°C for 7 h could dry 86.9% and 26.5% of the total moisture from the fresh radish slices respectively. The average rate of HEF drying from second hour to sixth hour was 0.025 g/min which was 0.0012 g/min higher than the oven-drying. Quality factors for HEF-dried radish exhibited less shrinkage, high absorption of water, better rehydration, less solids loss and better color than the oven-drying.     

HIGH ELECTRIC FIELD DRYING OF JAPANESE RADISH

Japanese radish (Raphanus sativus L.) slices were dried under an alternating current (AC) high electric field (HEF) of 430 kV/m using a multiple point electrode and a grounded copper mesh. HEF with multipoint to a mesh electrode system could evaporate 87.5% of the total moisture from fresh radish slices on 7 h exposure. Oven-drying at 60°C and ambient air at 25°C for 7 h could dry 86.9% and 26.5% of the total moisture from the fresh radish slices respectively. The average rate of HEF drying from second hour to sixth hour was 0.025 g/min which was 0.0012 g/min higher than the oven-drying. Quality factors for HEF-dried radish exhibited less shrinkage, high absorption of water, better rehydration, less solids loss and better color than the oven-drying.     

电场作用下荷电膜对多糖溶液的超滤性能

以分子量小于10000的右旋糖苷硫酸酯为分离对象,通过膜通量、截留率、膜通量衰减程度和膜的清洗恢复率等参数的测定,考察了外加直流电场作用下荷电超滤膜的分离性能。结果表明：与中性膜PES300相比,外加电场下荷电膜的膜通量和截留率都有所提高,而膜通量衰减程度由41．86％分别降低到19．51％和13．28％。结合使用膜改性和外加电场两种强化方法,膜的衰减程度可进一步降至8．33％,而且使用过的荷电膜清洗后其膜通量的恢复率可达到95％,表明能较大地改善膜的抗污染性能。     

PAN基凝胶聚合物电解质双电层电容器

为了得到安全、无泄漏、微型、超薄型的双电层电容器,采用内聚合方法制得聚丙烯腈基凝胶聚合物电解质双电层电容器,电解质的增塑剂为碳酸丙烯酯和碳酸乙烯酯,支持电解质为高氯酸锂,电极材料分别为比表面积1000m2/g和2600m2/g的活性炭。采用交流阻抗、循环伏安、恒流充放电、循环寿命等测试方法对内聚合式凝胶聚合物电解质及其组成的双电层电容器的性能进行了测试。结果表明,此种方法制得的双电层电容器的内阻小,比容量较大,其中以比表面积2600m2/g活性炭为电极材料的电容器的双电极比容量达到47.41F/g。     

不同模式电场增强活性炭电吸附钴(Ⅱ)的研究

自制活性炭电极,施加不同模式电场,探讨其对Co2+电增强吸附行为的影响。考察因素主要包括电压、溶液pH和离子强度。活性炭电极在阴极极化的条件下,交流伏安和方波伏安电场显著提高活性炭的吸附量,而恒电位和常规脉冲极谱无明显增强效果。溶液pH为5～7时,有利于活性炭对Co2+的电吸附。恒电位、常规脉冲极谱和恒电流电场适用于低盐溶液Co2+的吸附,而方波伏安电场适用于去除高盐溶液的Co2+。5种电场对活性炭的电脱附率均大于60%。     

辅助电场下局域分布纳米晶掺杂铌碲酸盐玻璃的制备

利用热处理温度场与辅助电场相匹配的技术,控制含AgCl的铌碲酸盐系统非线性光学玻璃的核化与析晶过程,进而可以精确控制玻璃中AgCl纳米晶体的析出.在300～350℃区域对TeO2-Nb2O5-BaO-AgCl系统玻璃进行辅助电场诱导下的热处理,可以获得尺寸均匀的AgCl纳米晶体.在热处理过程中加载电场与否将明显影响析出纳米晶体的尺寸和含量.热处理的同时利用电场的可局域加载的特性,可以在同一块玻璃中控制获得各种局域分布的纳米晶掺杂玻璃.     

直流电弧电渣钢包炉磁场强度的三维数值计算

推导了非规范正交曲线坐标系下，直流电弧电渣钢包炉磁场强度输运方程，并给出了相应的磁场强度的边界条件，进行了三维数值计算，预测结果与现场测量结果基本一致，所揭示的规律对实际生产有重要的指导意义．     

恒电场作用下煤吸附甲烷特征的研究

研究了四川白皎低变质无烟煤在直流１ ２００ Ｖ 下吸附甲烷的特征．结果表明：外加电场作用下煤吸附甲烷仍符合Ｌａｎｇｍ ｕｉｒ 等温吸附式, 吸附与解吸的动力学也符合三常数扩散控制模型和二常数经验公式; 恒电场使煤对甲烷的吸附能力降低 （ｂ 常数减小）, 但对动力学参数的影响不大．