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91.
天然气作为优质洁净的燃料将成为城市的主要能源之一,它具有热值高、安全性能好、清洁环保等优点。文章主要概述目前广州市天然气利用的状况,介绍了天然气改质制气工艺,从对天然气改质气的成分、燃烧特性、环保效益和经济效益的分析,最后得出结论:利用天然气进行裂解改质制气不但具有可行性,而且具有重要的现实意义。  相似文献   
92.
某炼油厂的重整加热炉采用热管空气预热器预热空气,开车后空气预热器烟气温降不足原设计的三分之一,分析了烟气量、炉膛漏风量、O2含量、CO2含量等因素对加热炉效率的影响,结果表明:加热炉系统漏风是根本原因.采用(1)调整烟道挡板以调节炉膛内的负压;(2)修补炉膛的漏点;(3)控制烟气出口的氧质量分数在4%以下这三种措施后,热管空气预热器的性能得到了保证,加热炉的运行效率得到了提高.  相似文献   
93.
Cysteine–cysteine chemokine receptor 5 (CCR5) has been discovered as a co-receptor for cellular entry of human immunodeficiency virus (HIV). Moreover, the role of CCR5 in a variety of cancers and various inflammatory responses was also discovered. Despite the fact that several CCR5 antagonists have been investigated in clinical trials, only Maraviroc has been licensed for use in the treatment of HIV patients. This indicates that there is a need for novel CCR5 antagonists. Keeping this in mind, the present study was designed. The active CCR5 inhibitors with known IC50 value were selected from the literature and utilized to develop a ligand-based common feature pharmacophore model. The validated pharmacophore model was further used for virtual screening of drug-like databases obtained from the Asinex, Specs, InterBioScreen, and Eximed chemical libraries. Utilizing computational methods such as molecular docking studies, molecular dynamics simulations, and binding free energy calculation, the binding mechanism of selected inhibitors was established. The identified Hits not only showed better binding energy when compared to Maraviroc, but also formed stable interactions with the key residues and showed stable behavior throughout the 100 ns MD simulation. Our findings suggest that Hit1 and Hit2 may be potential candidates for CCR5 inhibition, and, therefore, can be considered for further CCR5 inhibition programs.  相似文献   
94.
The mechanisms governing therapeutic resistance of the most aggressive and lethal primary brain tumor in adults, glioblastoma, have increasingly focused on tumor stem cells. These cells, protected by the periarteriolar hypoxic GSC niche, contribute to the poor efficacy of standard of care treatment of glioblastoma. Integrated proteogenomic and metabolomic analyses of glioblastoma tissues and single cells have revealed insights into the complex heterogeneity of glioblastoma and stromal cells, comprising its tumor microenvironment (TME). An additional factor, which isdriving poor therapy response is the distinct genetic drivers in each patient’s tumor, providing the rationale for a more individualized or personalized approach to treatment. We recently reported that the G protein-coupled receptor CCR5, which contributes to stem cell expansion in other cancers, is overexpressed in glioblastoma cells. Overexpression of the CCR5 ligand CCL5 (RANTES) in glioblastoma completes a potential autocrine activation loop to promote tumor proliferation and invasion. CCL5 was not expressed in glioblastoma stem cells, suggesting a need for paracrine activation of CCR5 signaling by the stromal cells. TME-associated immune cells, such as resident microglia, infiltrating macrophages, T cells, and mesenchymal stem cells, possibly release CCR5 ligands, providing heterologous signaling between stromal and glioblastoma stem cells. Herein, we review current therapies for glioblastoma, the role of CCR5 in other cancers, and the potential role for CCR5 inhibitors in the treatment of glioblastoma.  相似文献   
95.
炼化装置停工期间的腐蚀检查是设备腐蚀安全管理的重要环节.通过腐蚀检查,可以全面掌握装置的腐蚀状况,及时发现腐蚀隐患,分析腐蚀原因,提出有针对性的防护措施.对国内某炼化企业2.0 Mt/a连续重整装置开展了停工期间的腐蚀检查,分析装置的关键易腐蚀设备及其腐蚀原因.评价了上个运行周期材料防腐蚀和工艺防腐蚀措施的效果,探讨了腐蚀预测与实际腐蚀情况的差异,并就该装置主要腐蚀问题提出了防护措施及改进建议.  相似文献   
96.
主要阐述了Honeywell Experion PKS系统在中央控制室(甲醇流程监视控制、气化流程/逻辑监视控制及公用工程)的应用及升级改造。该系统的成功应用,提高了整个生产的效率,为公司创造了良好的经济效益。  相似文献   
97.
随着环保要求的提高以及芳烃工业的发展,大量的连续重整装置建成投产。反应器和再生器是连续重整装置中的核心设备之一,轴向条形筛网是制造其内部构件中心管和内外网的主要元件。在实际运行中,由常规轴向条形筛网制造的反应器和再生器的内件发生了较多的失效破坏,直接影响到了装置的正常连续生产。新型轴向条形筛网克服了传统轴向条形筛网的缺点,能够满足连续重整装置苛刻的工艺环境。  相似文献   
98.
连续重整装置再生器内网的失效破坏将直接影响装置的正常生产。介绍了近几年国内炼油厂再生器内网失效案例。从再生器内网的操作过程、温度分布、结构特点及制造工艺等方面对失效的性质、部位、形式等进行了分析。内网上半部在轴向方向上存在较大的温度梯度是损伤破坏的直接原因,内网所采用的轴向筛网结构和制造工艺的固有缺陷是其失效破坏的间接原因。传统的内网在使用过程中发生了较多的失效破坏,大多数损伤开裂出现在轴向的条形筛网二次成型的纵向焊接接头等结构突变和不连续处,损伤破坏的范围在内网上表面到以下600 mm范围内,也有部分失效是由于V型截面丝与支撑杆的焊点失效。  相似文献   
99.
A Japanese randomized controlled study showed that Interferon â (IFN-â1b) therapy is clinically effective in decreasing the frequency of attacks in multiple sclerosis (MS), even in optico-spinal MS (OSMS). However, recent studies have shown that IFN-â (IFN-â1a/IFN-â1b) treatment was not effective in neuromyelitis optica (NMO) patients and that the diminished benefit of IFN-â treatment in NMO may be due to different immune responses to IFN-â. We determined longitudinally the expression of CCR5, CXCR3 and CCR4 on CD4+ T and CD8+ T cells in the blood from patients with NMO and MS treated with IFN-â1b. During a 12-month period of IFN-â1b therapy, the annualized relapse rate decreased in MS patients but not in NMO patients. There was no significant difference in the expression of the chemokine receptors between NMO and MS at baseline. The percentages of CD4+CCR5+ and CD4+CXCR3+ T cells, representative of the Th1 response, were decreased in both NMO and MS after treatment. The percentage of CD4+CCR4+ T cells, representative of the Th2 response, was decreased in MS, but those for NMO was significantly increased compared with the pretreatment levels. Our results indicate that IFN-â1b-induced up-modulation of the Th2 response in NMO patients may be the source of differences in the therapeutic response to IFN-â1b therapy. In the present study, Th2 predominance is involved in the pathogenesis of NMO.  相似文献   
100.
对国内连续重整技术专利文献进行了检索,分析了国内专利申请情况,包括专利权人、总体技术发展趋势、研究热点等。分析表明,连续重整技术领域的申请量近年来呈快速增长趋势,中国、法国和美国申请人的申请量居于前列,其代表为中国石化、法国石油科学研究院(IFP)以及美国环球油品公司(UOP)。其中中国石化占据了50%的专利申请,IFP和UOP两公司占据了约25%的专利申请量。中石化在催化剂研制、催化剂再生技术和生产工艺及设备领域发明活跃。  相似文献   
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