等离子体辅助丙酮低温氧化的研究

考虑到小分子含氧组分在等离子体助燃体系中重要的研究意义,本文以丙酮为研究载体,基于先进的分子束质谱诊断平台开展了研究．提供了详细的中间体组分信息,并基于此构建了丙酮等离子体的低温反应网络．结果表明,在等离子体放电激励的作用下,丙酮的燃料氢提取过程被加速,并且还伴随着明显的燃料碎片化过程．研究发现,无势垒反应在等离子体低温氧化的反应机制中十分重要．另外,本文还给出丙酮低温氧化在不同电压激励下的定量结果．     

Growth-temperature-dependent optical and acetone detection properties of ZnO thin films

Zinc oxide (ZnO) thin films were prepared onto glass substrates at moderately low growth temperature by two-stage spray pyrolysis technique. The effects of growth temperature on structural, optical and acetone detection properties were investigated with X-ray diffractometry, a UV-visible spectrophotometer, photoluminescence (PL) spectroscopy and a homemade gas sensor testing unit, respectively. All the films are polycrystalline with a hexagonal wurtzite phase and exhibit a preferential orientation along [002] direction. The film crystallinity is gradually enhanced with an increase in growth temperature. The optical measurements show that all the films are physically highly transparent with a transmittance greater than 82% in the visible range. The band gap of the film is observed to exhibit a slight red shift with an increasing growth temperature. The PL studies on the films show UV/violet PL band at ～ 395 nm. Among all the films investigated, the film deposited at 250 ℃ demonstrates a maximum sensitivity of 13% towards 20 ppm of acetone vapors at 300 ℃ operating temperature.     

从油脚中提取粉状大豆磷脂的工艺试验

油脚经室温直接丙酮溶液浸出、真空脱溶干燥法制得了粉状大豆磷脂。产品含磷脂量达95%以上,色泽为淡黄色。     

丙酮污染对微型机械制冷机性能影响的实验研究

设计微型高压阀直接向机械制冷机内在线、连续地添加污染杂质,提出了制冷机丙酮污染的强化加速实验方案,从量化角度深入研究了污染对回热式机械制冷机性能影响的规律.实验分析表明,随着丙酮添加量的增加,制冷能力首先稍微增强,然后在42 mg和121 mg时分别出现了性能衰变的拐点.在间歇性开机时还发现了制冷机污染效应的时延现象.结合传热、流阻等理论对实验规律进行了分析讨论,为机械制冷机的可靠性技术和寿命预测研究奠定了基础.     

Cu-MgO/γ-Al2O3丙酮一步法合成甲基异丁基酮

采用等孔体积浸渍法制备Cu MgO/γ Al2O3丙酮常压气相加氢制MIBK催化剂.通过XRD及BET表面积测定表征催化剂.研究碱性组分及反应条件对转化率和选择性的影响,经筛选得到催化剂体系的最佳组成为:wCu=4%,wMgO=5%,适宜的反应条件为:常压,200℃,H2/丙酮摩尔比为2.5,进料速率为1.5ml·h-1·g-1cat.在该条件下,丙酮转化率达65.26%,MIBK选择性达57.49%.     

气相色谱法测定丙酮中还原性杂质

研究了用气相色谱仪测定丙酮中还原性杂质的方法．该法与化学分析法──“高锰酸钾试验”结果有较好的对应关系，为异丙苯法生产丙酮的质量指标控制提供简便、快速、准确的分析手段．     

烟用二醋酸纤维纺丝丙酮/空气混合气(VLA)高浓度控制及其应用

丙酮/空气混合气(VLA)中丙酮浓度是烟用二醋酸纤维丝束生产的一个重要工艺参数。文章以理论计算为指导,从干燥机VLA和纺丝机VLA丙酮浓度两方面,介绍了提高丙酮浓度的可行性,和高丙酮浓度运行下的控制方法。运行结果显示,在保证安全的前提下,提高纺丝VLA浓度,丙酮回收所需的蒸汽消耗显著降低,生产运营成本降低。     

Diisopropyl ether one-step generation from acetone-rich feedstocks

A one-step integrated process for the generation of the high-octane fuel ether, diisopropyl ether (DIPE), from acetone-rich feedstocks has been demonstrated. Three continuous, downflow, reactor configurations have been considered, including a two-bed catalyst design separated by inerts, gradient multicatalyst combinations, and an integrated two-zone layout with differing catalyst compositions. The bifunctional catalysts have both hydrogenation and etherification/dehydration capabilities and may comprise groups IB, VIB, and VIII metals incorporated into acidic, large and medium-pore zeolites, groups III or IV metal oxides, as well as heteropoly acid structures. DIPE syntheses are typically conducted at 100–165°C, under hydrogen pressure. The gradient reactor design, with careful choice of hydrogenation and etherification catalysts, allows DIPE to be generated in high selectivity and productivity. This revised version was published online in July 2006 with corrections to the Cover Date.     

PC微流控芯片黏接筋与溶剂的协同辅助键合

为了在微流控芯片上形成封闭的微通道等功能单元,克服热压键合中微流控结构的塌陷和热压所致芯片微翘曲对后续键合的影响,提出了一种适用于硬质聚合物微流控芯片的黏接筋与溶剂协同辅助的键合方法。以聚碳酸酯(PC)微流控芯片为研究对象,通过热压法在PC微流控芯片上的微通道两侧制作凸起的黏接筋,通过化学溶剂丙酮微溶PC圆片的表面,然后将PC圆片与带有黏接筋的PC微流控芯片贴合、加压、加热,从而实现微流控芯片的键合。分析了键合机理,并对键合工艺参数进行了优化。实验结果表明:键合质量受丙酮溶剂溶解PC圆片的时间和键合温度的影响,能够保证键合质量的最佳键合温度为80~90°,溶解时间为35~45s,芯片的键合总耗时为3min。与已有键合工艺相比,所提出的黏接筋与溶剂辅助键合工艺有效提高了键合效率。该键合方法不仅适用于具有不同宽度尺寸微通道的微流控芯片,还可扩展用于不同材料的硬质聚合物微流控芯片。