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91.
<正>0引言MLS4531生料立磨是北方重工集团的重要产品,在国内新型干法水泥生产线上大量应用,部分设备已运转超15年。磨辊作为磨机的主要研磨部件,在重载、高温、风蚀环境下工作,由于日常维护不到位或突发情况等原因而造成磨辊损伤的情况时有发生。当出现磨辊旋转油封损坏、磨辊轴承损坏等严重情况时,就要对磨辊进行拆卸,更换损坏的零部3  相似文献   
92.
Mechanical unloading contributes to significant cardiovascular deconditioning. Endothelial dysfunction in the sites of microcirculation may be one of the causes of the cardiovascular degeneration induced by unloading, but the detailed mechanism is still unclear. Here, we first demonstrated that mechanical unloading inhibited brain microvascular endothelial cell proliferation and downregulated histone deacetylase 6 (HDAC6) expression. Furthermore, HDAC6 promoted microvascular endothelial cell proliferation and attenuated the inhibition of proliferation caused by clinorotation unloading. To comprehensively identify microRNAs (miRNAs) that are regulated by HDAC6, we analyzed differential miRNA expression in microvascular endothelial cells after transfection with HDAC6 siRNA and selected miR-155-5p, which was the miRNA with the most significantly increased expression. The ectopic expression of miR-155-5p inhibited microvascular endothelial cell proliferation and directly downregulated Ras homolog enriched in brain (RHEB) expression. Moreover, RHEB expression was downregulated under mechanical unloading and was essential for the miR-155-5p-mediated promotion of microvascular endothelial cell proliferation. Taken together, these results are the first to elucidate the role of HDAC6 in unloading-induced cell growth inhibition through the miR-155-5p/RHEB axis, suggesting that the HDAC6/miR-155-5p/RHEB pathway is a specific target for the preventative treatment of cardiovascular deconditioning.  相似文献   
93.
Chemical vapor deposition(CVD)-grown graphene films on Cu foils,exhibiting fine scalability and high quality,are still suffering from the adverse impact of surf...  相似文献   
94.
相变微胶囊是一种性能良好、稳定性强的相变储能材料,其热导率偏低,但对相变微胶囊进行改性以及优化换热条件可以提高热导率。本文系统地介绍了相变微胶囊与改性相变微胶囊的制备方法,以及两者的区别。文章指出,对比分析可知,原位聚合法是制备改性相变微胶囊最常用的方法,对壁材进行改性是最常用的改性方法,并且在众多改性材料中氧化石墨烯是一种高导热、力学性能优异、稳定性强的改性材料。同时,文中对相变微胶囊和改性相变微胶囊在微通道换热器中的应用进行概述与总结,指出其中存在的问题:相变微胶囊与微通道换热器的结合,在提升换热效果的同时还存在着增加流动阻力和压降的问题。因此需要确定悬浮液流动的临界速度,充分发挥相变微胶囊与微通道换热器的优势。  相似文献   
95.
Classical molecular dynamics simulations are carried out to analyze the physical state of the catalyst, and the growth of single-wall carbon nanotubes under typical temperature and pressure conditions of their experimental synthesis, emphasizing the role of the catalyst/substrate interactions. It is found that a strong cluster/substrate interaction increases the cluster melting point, modifying the initial stages of carbon dissolution and precipitation on the cluster surface. Experiments performed on model Co-Mo catalysts clearly illustrate the existence of an initial period where the catalyst is formed and no nanotube growth is observed. To quantify the nature of the Co-Mo2C interaction, quantum density functional theory is applied to characterize structural and energetic features of small Co clusters deposited on a (001) Mo2C surface, revealing a strong attachment of Co-clusters to the Mo2C surface, which may increase the melting point of the cluster and prevent cluster sintering.  相似文献   
96.
针对传统基于置信度传播的立体匹配算法运算次数较多、效率低下的问题,提出一种快速收敛的置信度传播算法。该算法在计算每一个像素点的置信度时,只考虑当前像素点自适应大小邻域内像素点对它的信息传递,而忽略距离较远的像素点的影响。实验结果表明提出的算法在保持相近匹配精度的前提下,运算时间减少40%~50%,满足立体匹配的实时性要求。  相似文献   
97.
党翔吉  周玲  王艺璇  曾露 《金属学报》2017,22(4):477-480
目的: 探讨临床药师在慢性肾功能不全患者个体化应用抗栓药物治疗中的作用。方法: 回顾性分析临床药师参与1例慢性肾功能不全患者个体化抗栓药物治疗的案例。结果: 临床药师依据阿司匹林及依诺肝素药动学及药效学特征分析患者慢性肾衰竭及皮肤血肿形成原因,参与抗血栓治疗方案的调整,并为患者提供药学监护和用药教育。结论: 以关注特殊人群个体化用药,保证临床疗效,避免不良反应发生,保证患者用药合理、安全、有效、经济,可作为临床药师药学服务的切入点。  相似文献   
98.
In building performance simulation, occupant behavior contributes to large uncertainties, which often lead to considerable discrepancies between actual energy consumption and simulation results. This paper aims to extract occupant-behavior related electricity load patterns using classical K-means clustering approach at the initial investigation stage. Smart-metering data from a case study in Shanghai, China, was used for the load pattern analysis. The electricity load patterns of occupants were examined on a daily/weekly/seasonal basis. According to their load patterns, occupants were categorized as (a) white-collar workers, (b) poor or older families and (c) rich or young families. The daily patterns indicated that electricity use was much more random and fluctuated over a wide range. Most households of the monitored communities consumed relatively-low electricity; the characteristic double peak with higher level of consumption in the morning and evening were only apparent in a relatively small subset of residents (mostly white-collar workers). The weekly analysis found that significant load shifting towards weekend days occurred in the poor or old family group. The electricity saving potential was greatest in the white-collar workers and the rich or young family groups. This study concludes with recommendations to stakeholders utilizing our load profiling results. The research provides a rare insight into the electricity-use-related occupant behaviors of Shanghai residents through the case study of two communities. The findings of the study are also presented in a meaningful way so that they can directly aid the decision-making of governments and other stakeholders interested in energy efficiency. The research results are also relevant to the building energy simulation community as they are derived from observations, and thus can have the potential to improve the efficiency and accuracy of numerical simulation results.  相似文献   
99.
为提高现用经向多梭口织机的织造效率,降低因摩擦严重导致的纱线断头率,以M8300型多梭口织机为例,分析探讨现有多梭口织机织造滚筒工作原理及问题;详细分析了创新改进设计的双层织造滚筒的结构、开口结构及织造原理;介绍了三经两纬三维织物的特点。指出:双层织造滚筒织机采用带辅喷嘴的筘片及可旋转的开口装置,并在开口筘片与打纬筘片间增加滚动轴,可实现10根纬纱同时引入,完成三经两纬织物的织造,降低纱线断头率,提高织造效率和布面质量;经向多梭口织机今后研究的重点是减小筘片厚度或采用新开口机构,以提高经纱密度,减小经纱摩擦。  相似文献   
100.
为提高三维编织机的速度、降低其价格,利用三维设计软件Pro/E平台参数化设计思想,创新设计由行星齿轮系传动角齿轮的编织头结构系统,完成了零部件、虚拟样机装配等整台机器的结构设计;给出计算机CAD/CAM集成控制的编织机概念模型。指出:创新的五月柱型编织机的编织系统能针对编织的预成型件结构形状、纱线覆盖和纤维体积比参数要求快速进行编织;编织机无轨道板,传动平稳,能减少摩擦、磨损和振动;编织机灵活度和编织速度大幅提高,且价格相对低廉。  相似文献   
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