When does a vessel become a pipe?

The conditions under which the transient outflow from a punctured pipeline may be approximated as that emanating from a vessel using a simplified analytically based vessel blowdown model (VBM) is investigated in this article. The above addresses the fundamental drawback of long computational run times associated with the numerically based techniques used for simulating pipeline puncture failures. The efficacy of the VBM is tested by comparison of its predictions against simulation data obtained using a validated rigorous but computationally demanding numerical technique based on the method of characteristics. The results show that the accuracy of the VBM increases with decreasing puncture/pipe diameter ratio, line pressure, and increasing pipeline length. Surprisingly, the VBM produces more accurate predictions for two‐phase mixtures when compared with permanent gases. This is found to be a consequence of the better applicability of the isothermal bulk fluid decompression assumption within the pipeline in the case of two‐phase mixtures. © 2011 American Institute of Chemical Engineers AIChE J, 2011     

Batch Extractive Distillation in a Column with a Middle Vessel

Batch extractive distillation was studied in a column with a middle vessel. The process was simulated by a constant holdup model and solved by two point implicit method. Acetone and methanol mixture was separated in such a setup using water as solvent. The simulation agrees well with experimental results. The experimental and simulation results show that the solvent at the bottom and the product at the top of the column can be withdrawn simultaneously for a long period of time. It needs more time for the solvent to reach high purity than that required for the more volatile component to reach high purity, so that the time to withdraw solvent from the bottom is delayed.     

Lending a Hand to Recyclers with a Low—Density Adhesive

研究在一般EVA热熔胶中用聚丁烯取代20％～50％的松香酯，使胶的密度从0．975降至0．936～0．970范围，结果表明不影响热熔胶性能．但成本可下降，尤其较易在纸浆工序中清除。     

耐热性a氰基丙烯酸酯胶粘剂

发明的详细说明: 本发明是关于具有耐热性能的α-氰基丙烯酸酯系胶粘剂.α-氰基丙烯酸酯系胶粘剂是非溶剂型、一液性单体型的胶粘剂,藉助于被粘物表面或空气中微量水分,很容易聚合固化形成具有较高粘接强度的胶粘剂. 但是,α-氰基丙烯酸酯聚合体属于热塑性聚合物,因而一旦受热,其粘接强度就比受热前大大降低.这就是α-氰基丙烯酸酯胶粘剂的一大缺点.     

The biodesulphurization of a semianthracite coal in a packed-bed system☆

The purpose of this study was to improve the desulphurization yield of a high sulphur-content semianthracite from northern Spain adapted to the process conditions of a packed-bed reactor, for which three 5-kg packed columns of coal were set up with the pH stabilized at 1.5. The process was begun by inoculating the first column with a culture obtained from micro-organisms native to the coal itself, mainly Thiobacillus ferrooxidans and Leptospirillum ferrooxidans, grown in a stirred reactor. The percolate of this column was then used to seed the second column, the percolate of which was then inoculated into the last one. The purpose was to obtain from the last column a better adapted and more active biomass which would give a better desulphurization yield for coal. Results show an increased yield from the first column to the last over the first 20 days of treatment, but the total desulphurization in the third column was less than expected, owing to a high precipitation of jarosite.     

Is a Calorie Really a Calorie? Metabolic Advantage of Low-Carbohydrate Diets

The first law of thermodynamics dictates that body mass remains constant when caloric intake equals caloric expenditure. It should be noted, however, that different diets lead to different biochemical pathways that are not equivalent when correctly compared through the laws of thermodynamics. It is inappropriate to assume that the only thing that counts in terms of food consumption and energy balance is the intake of dietary calories and weight storage. Well-controlled studies suggest that calorie content may not be as predictive of fat loss as is reduced carbohydrate consumption. Biologically speaking, a calorie is certainly not a calorie. The ideal weight loss diet, if it even exists, remains to be determined, but a high-carbohydrate/low-protein diet may be unsatisfactory for many obese individuals.     

CFC114a或HCFC124氢化脱卤制备HFC134a

1前言1,1,1,2-四氟乙烷（CF3CH2F或HFC134a）由于其ODP值为零,对臭氧层没有破坏作用而广泛地用作民用制冷和汽车空调制冷剂CFC12的潜在替代物,同时它还用作发泡剂、喷雾剂和溶剂。该产品的生产合成路线很多,其中通过氢化还原制备的方法主要有1,1-二氯-1,2,2,2-四氟乙烷（CCl2FCF3或CFC114a）或1-氯-1,2,2,2-四氟乙烷（CHClFCF3,或HCFC124）加氢脱卤两条途径。美国的DUPont,日本的Daikin,Asahi,英国的ICI,法国的Atochem等大公司在这方面进行了大量的研究工作。这一方法的关键是选择具有高活性、高选择性…     

G Protein-Coupled Receptors: What a Difference a ‘Partner’ Makes

G protein-coupled receptors (GPCRs) are important cell signaling mediators, involved in essential physiological processes. GPCRs respond to a wide variety of ligands from light to large macromolecules, including hormones and small peptides. Unfortunately, mutations and dysregulation of GPCRs that induce a loss of function or alter expression can lead to disorders that are sometimes lethal. Therefore, the expression, trafficking, signaling and desensitization of GPCRs must be tightly regulated by different cellular systems to prevent disease. Although there is substantial knowledge regarding the mechanisms that regulate the desensitization and down-regulation of GPCRs, less is known about the mechanisms that regulate the trafficking and cell-surface expression of newly synthesized GPCRs. More recently, there is accumulating evidence that suggests certain GPCRs are able to interact with specific proteins that can completely change their fate and function. These interactions add on another level of regulation and flexibility between different tissue/cell-types. Here, we review some of the main interacting proteins of GPCRs. A greater understanding of the mechanisms regulating their interactions may lead to the discovery of new drug targets for therapy.     

5000t/a油性涂料、3000t/a水性涂料、2000t/a合成树脂建设项目

<正>该项目位于湖北省咸宁市嘉鱼畈湖工业园,由湖北煜森防腐涂料科技有限公司投资建设,项目建设内容:湖北煜森防腐涂料科技有限公司建设5000t/a油性涂料、3000t/a水性     

20kt/a碳酸铵、40kt/a锂离子电解液材料、20kt/a氨基甲酸铵、30kt/a单氰胺、10kt/a胍基乙酸项目

正本项目位于浙江省滁州市炉桥镇盐化工业园,由滁州东宇新材料科技有限公司投资建设,新建综合楼、办公楼、研发楼、生产车间、动力车间、仓库、公用工程车间、堆场、罐区等总建筑面积24485平方米。购置反应釜、搅拌釜、蒸馏釜、水解釜、结晶釜、运输泵、蒸馏塔、储罐、离心机、干燥机、粉碎机等生产设备。以及供电、给排水、绿化、消防等附属设施建设。项目建成达产后可形成年产20kt碳酸铵、40kt锂离子电     

磷铵90kt/a改120kt/a技术特点述评

介绍由四川省化工设计院和银山公司设计室负责施工图设计的 9万吨 /年磷铵扩能为 12万吨 /年工艺的技术特点 ,采用双槽萃取—两效三体料浆浓缩—烟气加热空气制粉状磷酸一铵工艺路线。并采用了一系列新工艺、新技术 ,2 0 0 0年装置投入运行 ,经考核达到设计能力 ,最大产量达 487t/ d磷铵。最后提出需解决辅助装置能力配套问题及国产减速机大型化问题     

巨化134a项目开工

最近。巨化股份公司134a项目开工建设，并以此拉开了巨化集团公司第三次创业序幕。随着我国国民经济的发展和人民生活水平的提高，电冰箱、空调、汽车等高消费商品的生产量及需求量日益增长，氟制冷剂也为人们熟悉。目前我国的氟制冷剂普遍采用的是氟氯烃化合物即CFCs，而CFCs是消耗臭氧层物质，对大气臭氧层有破坏作用，根据《蒙特利尔议定书》规定，发展中国家应该在2010年以前停止消耗臭氧层物质ODS的生存和使用。