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991.
王心良 《西华师范大学学报(哲学社会科学版)》1997,18(4):331-333
将废旧油泵改装,制成循环水泵,并用于几种不同沸点化合物的减压蒸馏,对所获实验数据进行分析,结果表明该改制泵真空度高,抽气量大,简便,经济和耐用。 相似文献
992.
Beatriz Palmarola-Adrados Mats Galbe Guido Zacchi 《Applied biochemistry and biotechnology》2004,115(1-3):989-1002
Steam treatment of an industrial process stream, denoted starch-free wheat fiber, was investigated to improve the formation
of monomeric sugars in subsequent enzymatic hydrolysis for further bioconversion into ethanol. The solid fraction in the process
stream, derived from a combined starch and ethanol factory, was rich in arabinose (21.1%), xylose (30.1%), and glucose (18.6%),
in the form of polysaccharides. Various conditions of steam pretreatment (170–220°C for 5–30 min) were evaluated, and their
effect was assessed by enzymatic hydrolysis with 2 g of Celluclast + Ultraflo mixture/ 100 g of starch-free fiber (SFF) slurry
at 5% dry matter (DM). The highest overall sugar yield for the combined steam pretreatment and enzymatic hydrolysis, 52g/100
g of DM of SFF, corresponding to 74% of the theoretical, was achieved with pretreatment at 190°C for 10 min followed by enzymatic
hydrolysis. 相似文献
993.
高丰度硼-10主要是通过精馏与化学交换法进行制备,在交换反应过程中,液相络合剂的研究非常重要.为此以苯甲醚、硝基甲烷、丙酮、甲基异丁基酮作为络合刑进行了系统的实验研究.设计了合成络合物体系的实验反应器,并用这些络合荆分别与三氟化硼合成了4种络合物体系.对这4种络合物体系的密度、凝固点、BF3/络舍剂比率以及蒸气压等性能进行了实验研究,并拟合了蒸气压随温度变化的曲线,通过分析认为苯甲醚更适宜于应用在硼同位素的分离过程中,能减少能耗,降低成本. 相似文献
994.
在工业锅炉生产工艺流程的基础上,介绍了UHG-311-G型双冲量连续式水位控制器在工业蒸汽锅炉控制系统中的工作原理,并对命名用时应注意的问题进行了提示. 相似文献
995.
卢世荣 《天津理工大学学报》2004,20(3):84-86
借助数学方法,结合相律中自由度数的分析,用拉乌尔(Raoult)定律、安托尼(Antoine)方程表述两组分均相混合溶液的温度与气相组成、温度与液相组成以及气相组成与液相组成的相平衡关系.综合相图、相律及相平衡关系,分析精溜操作中的状态参数,使抽象的相平衡内容具体、直观. 相似文献
996.
精馏、吸收严格计算中焓的计算方法 总被引:1,自引:0,他引:1
田庆来 《河北理工学院学报》2002,24(1):81-84
总结了适合于精馏、吸收严格计算的焓的计算方法,并对各种条件下的精馏、吸收计算,推荐了焓的计算方法。 相似文献
997.
998.
Milliseconds process to produce hydrogen by steam methane reforming (SMR) reaction, based on Ni catalyst rather than noble catalyst such as Pd, Rh or Ru, in micro-channel reactors has been paid more and more attentions in recent years. This work aimed to further improve the catalytic performance of nickel-based catalyst by the introduction of additives, i.e., MgO and FeO, prepared by impregnation method on the micro-channels made of metal-ceramic complex substrate. The prepared catalysts were tested in the same micro-channel reactor by switching the catalyst plates. The results showed that among the tested catalysts Ni-Mg catalyst had the highest activity, especially under harsh conditions, i.e., at high space velocity and/or low reaction temperature. Moreover, the catalyst activity and selectivity were stable during the 12 h on stream test even when the ratio of steam to carbon (SIC) was as low as 1.0. The addition of MgO promoted the active Ni species to have a good dispersion on the substrate, leading to a better catalytic performance for SMR reaction. 相似文献
999.
Jorge Vicente Javier Erea Martin Olazar Pedro L.Benito Javier Bilbao Ana G.Gayubo 《天然气化学杂志》2014,(5):639-644
Ethanol steam reforming has been studied in a fluidized bed (in order to ensure bed isothermicity) on commercial catalysts for methane reforming. The results allow analyzing the effect of temperature (in 300-700℃ range), and both metal and support nature on the reaction indices (ethanol conversion, yields and selectivities to H2 and byproducts (CO2, CO, CH4 and C2H4O)). Special attention has been paid to catalysts' stability by comparing the evolution of the reaction indices with time on stream at 500°C (minimum CO formation) and 700℃ (minimum deactivation by coke deposition). Although they provide a slightly lower H2 yield, the results evidence a good behaviour of Ni based catalysts, indicating that they are an interesting alternative of more expensive Rh based ones. 相似文献
1000.
Conversion of (1H)‐1,2,4‐triazole to its sodium salt with methanolic sodium methoxide is followed by reaction with iodomethane. A scalable approach that overcomes problems associated with water‐soluble starting material and water‐soluble product combined continuous extraction (chloroform/water) with a final short‐path distillation under a controlled vacuum to obtain spectroscopically pure 1‐methyl‐1,2,4‐triazole in 63% yield. Adaptation to microwave synthesis conditions, while providing a faster reaction time, offers no product yield or purification advantages over the conventional approach described. Conversions of this product to related derivatives such as 1,4‐dimethyl‐1,2,4‐triazolium iodide and 1‐methyl‐1,2,4‐triazolium hydrochloride are readily achieved. 相似文献