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71.
以4-氯-2-氟-酰替苯胺为原料,经硝化,还原,重氮化,与巯基乙酸作用,水解反应制得化合物2-氯-4-氟-5-胺基苯基硫代乙酸甲酯,以4-氯-2-氟-5酰替苯胺为原料经酰化,还原,缩合制得化合物2-氯-4-氟-5-甲氧羰基硫代乙酸甲酯。通过比较2条工艺方法的优缺点确定了最佳工艺路线。 相似文献
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In the pharmaceutical industry, the production of granules is based on a batch concept. This concept offers many advantages, as a batch can be accepted or rejected. However, the scale-up of the batch size may lead to problems. The variety of the equipment involved does not facilitate the scale-up process and the capital invested in space and equipment is high. An alternative approach is the use of a continuous process. However, continuous processes have the disadvantage among others that the batch size is not well defined. Thus, a special quasi-continuous production concept was developed, taking into account the advantages of a batch type and a continuous process. This concept was developed in cooperation with the Institute of Pharmaceutical Technology of the University of Basel, Glatt CH-4133 Pratteln and F. Hoffmann-La Roche, CH-4070 Basel. The equipment allows to implement a “Just in Time Production Concept” as a large batch B consists of n subunit (SU) batches b, i.e. B=nb. The subunit batch b corresponds to, e.g. 7-kg material for the production of pharmaceutical granules for further processing such as tabletting. At the Roche production site, this novel process equipment was used to manufacture batch sizes B with n=10, n=100 and so far up to n=600 subunits. This leads to an optimal use of capital invested in GMP space and equipment. The difference to the classical scale-up is the following: with classical scale-up, the dimensions of the equipment x, y, z is enlarged and the process time is more or less kept constant. With this novel concept, the dimension x, y, z of the equipment is kept constant and the process is repeated in the 4th dimension “n times”. Thus, for the scale-up in the 4th dimension, i.e. in the time, the equipment needs to show a “self-cleaning” property and appropriate formulations. The novel concept is of special interest, as the quality of the product is not changed during scale-up. 相似文献
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Quantified mass transfer and superior antiflooding performance of ordered macro‐mesoporous electrocatalysts 下载免费PDF全文
Min Jie Wang Tao Zhao Wei Luo Zhan Xin Mao Siguo Chen Wei Ding Yonghui Deng Wei Li Jing Li Zidong Wei 《American Institute of Chemical Engineers》2018,64(7):2881-2889
For oxygen reduction reaction (ORR), constructing porous catalysts are highly important for mass transfer inside. However, the various porous structures usually possess significantly different water buffer efficiency, that is, the antiflooding capability, for which one is still difficult to give a quantitative evaluation. In this work, we designed a special “rattle‐drum” like working electrode, by which an exactly quantitative assessment on the mass transfer efficiencies can be conducted. Particularly, ordered macro‐mesoporous Pt/C shows quantified mass transfer and antiflooding efficiency to be four times high as that of the commercial one. This observation should be attributed to their different pore characteristics, as the dual‐porosity Pt/C has 3.4 times the pore volume of the commercial one, together with regular pore arrangement. Simultaneously, it also demonstrated excellent durability, indicating that the macro‐mesoporous Pt/C indeed owns high stability in both antiflooding and durability. © 2018 American Institute of Chemical Engineers AIChE J, 64: 2881–2889, 2018 相似文献
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韧性概念的重新审视 总被引:3,自引:0,他引:3
自《2005—2015兵库行动框架》被采纳以来,受灾社区的恢复力紧密取决于受灾社区的韧性,已经成为灾害风险控制项目的共同特征。现在人们越来越多地关注受灾社区在灾难发生后不依靠或少依靠外部援助而"反弹"或恢复的能力。与其仅仅关注受灾对象的需求和弱点,不如把着眼点放在应对灾难的韧性上,这突出了灾害风险控制领域需要转变。然而在灾害学界的研究和学术领域,对韧性这一概念达成共识依然是个挑战。本文梳理了不同情况下韧性的定义,脆弱性在韧性主题中所扮演的角色和意义,以及脆弱性和韧性之间的差异。文章最后探讨和总结了韧性思维在我们认识和应对灾害时所具有的指导意义。 相似文献
76.
大量高铁铝土矿因氧化铁含量高、矿物嵌布关系复杂而处于待开发状态。为确定四川某高铁铝土矿的高效开发利用方案,对还原焙烧—弱磁选提铁—铝溶出的铝铁高效分离回收工艺中主要影响因素——焙烧制度、焙烧产物磨矿细度及弱磁选磁场强度进行了单因素条件试验。结果表明,在还原焙烧试样粒度为0.18~0 mm、配碳系数为2.0、焙烧温度为1 350℃、焙烧时间为20 min、焙烧产物磨矿细度为-0.074 mm占91%、弱磁选磁场强度为60kA/m情况下,可取得铁品位为89.83%、铁回收率为84.08%的金属铁粉,Al2O3浸出率为69.35%,较好地实现了铝、铁分离。 相似文献
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