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1.
朱红玉 《燃料与化工》2003,34(3):131-133
介绍了常压间歇式循环催化改质制气装置的工艺特点、投产过程中出现的问题及处理方法。  相似文献   
2.
To overcome some of the limits of existing metallic alloys, a new alloy design concept has been introduced recently in order to control the crystallinity, i.e. to utilize crystalline, quasicrystalline, and amorphous structures. In particular, bulk metallic glasses (BMGs) receive great attention because of their unique properties due to their different atomic configuration. Recently, significant progress in enhancing glass forming ability (GFA) has led to the fabrication of BMGs having potential for application as structural and functional materials. Moreover, successful design of BMG matrix composite microstructure suggests that the plasticity of BMGs can be controlled properly. In this review article, we introduce recent research results on the design of BMGs with high GFA and on the enhancement of plasticity in metallic glass matrix composites.  相似文献   
3.
本文实现了一个基于综合匹配法的汉字识别后处理系统,该方法既利用了帝级识别结果的信息,又利用了汉语中字的上下文制约关系,即组字成词的信息,同时用了词的使用频度。  相似文献   
4.
夏春玲 《当代化工》2015,(4):845-846
阐述了做好重整装置首次开工的几个关键因素:做好预处理开工工作,确保重整进料合格;做好重整催化剂的处理工作;把好重整进油后480℃温度关;遵守操作规程,平稳操作。  相似文献   
5.
中国石油化工股份有限公司金陵分公司连续重整装置采用UOP超低压专利技术,设计规模1.0 M t/a。装置运行过程中发现因循环水质量差和流量小导致增压机冷却效果差;因重整产氢纯度低导致其中C2以上烃类在氢还原气氛下发生氢解反应;电阻丝局部积炭,热量传递效果变差;氧化镁绝缘层过热变薄失去绝缘效果,致使还原电加热器接地故障跳停;因抽提塔界面波动过大、溶剂脏、消泡剂泵故障、汽提塔负荷增大引起汽提塔冲塔等问题。提出了优化循环水流程、改造抽空器、引用PSA高纯度氢作为还原氢、降低抽提溶剂比、改变异构化轻烃流程等一系列措施,基本解决了制约装置长周期运行的问题。同时也指出了制约装置大负荷生产存在的"瓶颈"。  相似文献   
6.
7.
Polycystic ovary syndrome (PCOS), which affects 5–10% of women of reproductive age, is associated with reproductive and metabolic disorders, such as chronic anovulation, infertility, insulin resistance, and type 2 diabetes. However, the mechanism of PCOS is still unknown. Therefore, this study used a letrozole-exposed mouse model in which mice were orally fed letrozole for 20 weeks to investigate the effects of letrozole on the severity of reproductive and metabolic consequences and the expression of cysteine–cysteine motif chemokine receptor 5 (CCR5) in letrozole-induced PCOS mice. The letrozole-treated mice showed a disrupted estrous cycle and were arrested in the diestrus phase. Letrozole treatment also increased plasma testosterone levels, decreased estradiol levels, and caused multicystic follicle formation. Furthermore, histological analysis of the perigonadal white adipose tissue (pgWAT) showed no significant difference in the size and number of adipocytes between the letrozole-treated mice and the control group. Further, the letrozole-treated mice demonstrated glucose intolerance and insulin resistance during oral glucose and insulin tolerance testing. Additionally, the expression of CCR5 and cysteine-cysteine motif ligand 5 (CCL5) were significantly higher in the pgWAT of the letrozole-treated mice compared with the control group. CCR5 and CCL5 were also significantly correlated with the homeostasis model assessment of insulin resistance (HOMA-IR). Finally, the mechanisms of insulin resistance in PCOS may be caused by an increase in serine phosphorylation and a decrease in Akt phosphorylation.  相似文献   
8.
Kynurenic acid (KYNA) is implicated in antiinflammatory processes in the brain through several cellular and molecular targets, among which microglia-related mechanisms are of paramount importance. In this study, we describe the effects of KYNA and one of its analogs, the brain-penetrable SZR104 (N-(2-(dimethylamino)ethyl)-3-(morpholinomethyl)-4-hydroxyquinoline-2-carboxamide), on the intracellular distribution and methylation patterns of histone H3 in immunochallenged microglia cultures. Microglia-enriched secondary cultures made from newborn rat forebrains were immunochallenged with lipopolysaccharide (LPS). The protein levels of selected inflammatory markers C–X–C motif chemokine ligand 10 (CXCL10) and C–C motif chemokine receptor 1 (CCR1), histone H3, and posttranslational modifications of histone H3 lys methylation sites (H3K9me3 and H3K36me2, marks typically associated with opposite effects on gene expression) were analyzed using quantitative fluorescent immunocytochemistry and western blots in control or LPS-treated cultures with or without KYNA or SZR104. KYNA and SZR104 reduced levels of the inflammatory marker proteins CXCL10 and CCR1 after LPS-treatment. Moreover, KYNA and SZR104 favorably affected histone methylation patterns as H3K9me3 and H3K36me2 immunoreactivities, and histone H3 protein levels returned toward control values after LPS treatment. The cytoplasmic translocation of H3K9me3 from the nucleus indicated inflammatory distress, a process that could be inhibited by KYNA and SZR104. Thus, KYNA signaling and metabolism, and especially brain-penetrable KYNA analogs such as SZR104, could be key targets in the pathway that connects chromatin structure and epigenetic mechanisms with functional consequences that affect neuroinflammation and perhaps neurodegeneration.  相似文献   
9.
根据某公司连续重整装置的实际运行情况,从原料和催化剂再生注氯等方面分析了氯的来源,阐述了氯对装置各系统的影响,并提出了相应的解决方案.在预加氢系统中采用连续注水冲洗的方法,防止其结盐堵塞和腐蚀;在重整系统中增设脱氯设施,降低氯含量,减轻氯对后续装置的影响;采用树脂在线脱氯技术净化溶剂,脱除苯抽提系统溶剂中的氯,减缓溶剂...  相似文献   
10.
介绍了镇海炼油化工股份有限公司1.0Mt/a连续重整装置四合一加热炉的设计,通过对炉型选取,管路系统、燃烧器及余热回收系统等设计内容分析总结,为今后大型化连续重整装置加热炉设计与生产积累有益的经验。  相似文献   
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