Preparation of phenolic resin derived 3-D ordered macroporous carbon

Three-dimensionally ordered long-range macroporous carbon structures were prepared using commercially available phenolic resin by utilizing sacrificial colloidal silica crystalline arrays as templates that were subsequently removed by HF etching after pyrolysis in an argon atmosphere. SEM, TEM, and BET were employed to characterize the morphology and the surface area of the porous carbon structures. The pore size (150–1000 nm) and BET surface area, which reflect pore volume (298.6 m²/g (1.32 cm³/g) ∼ 93.7 m²/g (0.12 cm³/g)), of the macroporous carbon structures produced were approximately proportional to the size (150–1000 nm) of the sacrificial silica sphere templates used (annealing temp. 550°C). The achieved 550 nm porous carbon structures were examined to function as potential catalyst carriers and were successfully impregnated with Ag or Pt-Ru on their inner walls after borohydride reduction at room temperature. In addition, porous carbon patterns were fabricated using the ‘micromolding in capillary’ technique, which has potential applications in the microreaction technology.     

毛细管电泳法测定银杏叶片中的橙皮素、芦丁和槲皮素

建立了一种利用毛细管电泳测定银杏叶片中橙皮素、芦丁和槲皮素的方法。研究了缓冲溶液pH值和浓度、分离电压和进样时间对分离的影响，在优化的条件下，10min内实现了三种物质的良好分离。橙皮素、芦丁和槲皮素分别在0．03～0．80、0．06～0．00，0．04～0．90mg/mL浓度范围内和峰电流成线性关系，线性相关系数分别为0．9992、0．9976、0．9991，检出限分别为0．005、0．009和0．006mg/mL。     

毛细管气相色谱法同时测定三磷酸胞苷二钠中5种有机溶剂残留量

研究建立了同时测定三磷酸胞苷二钠中乙醇、丙酮、氯甲醚、甲苯、苯乙烯5种有机溶剂残留量的毛细管气相色谱法。样品以乙腈为溶剂,经DB-FFAP(30 m×0.32 mm×0.25μm)毛细管柱分离,氢火焰离子化检测器检测,这5种有机溶剂呈良好的线性响应,平均回收率在98.3%~99.5%,精密度RSD在0.21%~1.92%,最低检出限可达5.0~7.5 mg/kg。本方法简单、灵敏、准确,完全能满足药品中所述有机溶剂残留量的测定要求。     

Mass transfer from Taylor bubbles rising in single capillaries

Gas-liquid mass transfer from Taylor bubbles rising in 1, 2 and 3 mm diameter capillaries of circular and square cross-sections was investigated for air-water system. The liquid-phase volumetric mass transfer coefficient k_La was obtained from experimental oxygen absorption dynamics. The experimental k_La values are in good agreement with the model developed by van Baten and Krishna (2004. Chemical Engineering Science 59, 2535-2545), with the additional assumption that the dominant mass transfer contribution is to the film surrounding the bubble.     

气体作冷却润滑剂的绿色切削试验

为实现绿色切削,研究了无污染、无危害的冷却润滑技术.采用氮气、氧气、二氧化碳气、氩气及过热水蒸气作冷却润滑剂,进行了单因素切削试验.试验结果表明,这些气体冷却润滑剂可以减小切削变形、切削力,降低切削温度,改善加工表面形貌.根据试验结果和冷却润滑作用机理分析可知,气体在切削中具有一定的冷却润滑作用,同时具有来源广泛、无毒害和污染、不用回收处理等绿色特点,故气体具备绿色切削的潜力.     

季冻区高速公路路基冻害调查及试验观测

在对吉林省几条高速公路进行的野外冻害调查、现场观测和室内冻胀、水分迁移模拟试验的基础上,依据取得的野外资料和室内试验数据,对季冻区高速公路路基冻害的原因和影响因素进行分析和探讨;对冻害与水分关系、路基冻害水分来源、水分迁移特征以及由于路面底基层二灰土性能恶化失效导致的道路翻浆等问题进行了深入研究.同时利用本项目综合研究的特点,将竖管法毛细水沿高度分布的研究资料与由冻胀试验揭示的各种冻胀率——含水量变化规律有机结合起来进行分析,从而得到了毛细水冻害有效高度,试验结果表明:规范值相对试验值在一些情况下偏低,有的低很多,对路基防冻抗冻设计不利.研究成果对公路路堤最小高度设计和挖方段防冻处理深度设计等防冻措施的采用有实际意义.     

Mathematical model of shear rate of polymer melt dynamic extruding through capillary

With superimposing a sine vibration of displacement on the extruding direction of a polymer melt, the characterization formula of the shear rate of a polymer melt within a capillary was set up. By making use of the experimental equipment of a constant velocity type dynamic rheometer of capillary (CVDRC) designed by the authors, the calculating steps of the shear rate of the polymer melt at the wall of the capillary under a vibration force field were established. Through measuring and analyzing the instantaneous data of capillary entry pressure, capillary volume rate, and their phase‐difference under the superimposed vibration, the polymer melt's shear rate at the wall of the capillary can thus be calculated. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 95: 1056–1061, 2005     

毛细管膜生物反应器中加沸石对膜污染的影响

通过处理生活污水时毛细管膜污染状况的研究，考察了膜水通量随沸石投加量而变化的情况。在操作压力为0．025MPa，膜面流速为0．8m/s，p(MLSS)为3000mg／L的条件下，与不投加沸石直接处理生活污水相比，沸石的投加使膜水通量上升，总阻力下降；试验还探讨了沸石最佳投加量问题。结果表明，沸石的投加可改善膜面泥饼性质，提高水通量，是一种积极的膜污染防治手段。     

温度驱动下风积砂毛细现象试验研究

为了研究环境温度对毛细水上升过程的影响,进行了室内砂柱模拟试验。设置了两组不同温度下砂柱毛细水上升试验进行对比,分析了风积砂毛细水上升高度随时间的变化规律以及与温度的关系,探讨了毛细水上升的运动机理。试验结果表明:外部条件相同的情况下,较高的温度能够加快湿润锋的迁移速率,然而局部的高温会抑制水分的向上迁移,但温度效应不是特别明显。     

20钢水平连铸圆管坯轧制的钢管内部发纹研究

介绍了用水平连铸圆管坯轧制钢管的内部发纹及显微组织情况 ,得出内部发纹是一种由 (Mn、Fe)S和疏松点、α -Fe构成的偏析带 ,是由管坯带来的 ;轻微内部发纹的存在对钢管的使用性能不会造成较大影响。