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使用正时皮带的柴油机高压油泵相位的优化设计

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内燃机与配件 2024年第6期 57-60页

作者：陈尚荣王慧韦俊潍柴动力扬州柴油机有限责任公司江苏扬州225131

为提升柴油机正时系统的可靠性,本文分析了使用正时皮带的柴油机中高压油泵的安装相位对正时系统的影响。针对某3L排量柴油机的高压油泵安装相位进行研究,利用AVL多体动力学软件Excite Timing Drive对正时系统进行动态仿真分析,确认高... 详细信息

为提升柴油机正时系统的可靠性,本文分析了使用正时皮带的柴油机中高压油泵的安装相位对正时系统的影响。针对某3L排量柴油机的高压油泵安装相位进行研究,利用AVL多体动力学软件Excite Timing Drive对正时系统进行动态仿真分析,确认高压油泵最优相位下正时张紧器的摆角、皮带振幅等参数,并通过对比试验验证。结果表明,高压油泵在最优相位下,可有效避开正时系统周期性扭矩叠加,最大程度的降低正时系统承受的扭矩及冲击,提升正时皮带的可靠性。

关键词：正时皮带高压油泵相位

Effect of Mathematical Expression of Vegetation Indices on the Estimation of Phenology Trends from Satellite Data

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Chinese Geographical Science 2019年第5期29卷 756-767页

作者： ZUO Lu LIU ronggao LIU Yang shang rong State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing100101China University of Chinese Academy of Sciences Beijing100049China

Vegetation indices(VIs) from satellite remote sensing have been extensively applied to analyze the trends of vegetation phenology. In this paper, the NDVI(normalized difference vegetation index) and SR(simple ration), which are calculated from the same spectral bands of MODIS data with different mathematical expressions, were used to extract the start date(SOS) and end date(EOS) of the growing season in northern China and Mongolia from 2000 to 2015. The results show that different vegetation indices would lead to differences in vegetation phenology especially in their trends. The mean SOS from NDVI is 15.5 d earlier than that from SR, and the mean EOS from NDVI is 13.4 d later than that from SR. It should be noted that 16.3% of SOS and 17.2% of EOS derived from NDVI and SR exhibit opposite trends. The phenology dates and trends from NDVI are also inconsistent with those of SR among various vegetation types. These differences based on different mathematical expressions in NDVI and SR result from different resistances to noise and sensitivities to spectral signal at different stage of growing season. NDVI is prone to be effected more by low noise and is less sensitive to dense vegetation. While SR is affected more by high noise and is less sensitive to sparse vegetation. Therefore, vegetation indices are one of the uncertainty sources of remote sensing-based phenology, and appropriate indices should be used to detect vegetation phenology for different growth stages and estimate phenology trends.

关键词： vegetation phenology vegetation index trend consistency noise effect spatially temporal comparability northern China Mongolia

Regulated conformation changes in C-reactive protein orchestrate its role in atherogenesis

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Chinese Science Bulletin 2013年第14期58卷 1642-1649页

作者： MA Xiao JI shang-rong WU Yi School of Mechano-Electronic Engineering Lanzhou University of Technology School of Life Sciences Lanzhou University

C-reactive protein (CRP) is a prototypic human acute phase reactant composed of five identical subunits. Emerging evidence indicates that CRP is not merely a predictor of cardiovascular disease, but may also be a direct mediator. However, the diverse and sometimes contradictory activities of CRP have considerably hampered the attempts to define the exact role of CRP in atherogenesis. Here, we review the multiple layers of regulation of CRP's structure and function, highlighting how local inflammation conditions, such as the abundance of damaged cell membranes and redox homeostasis, can tip the balance of the pro-and antiinflammatory activities of CRP. We propose that the highly controlled interplay between different structural conformations of CRP underlies its intrinsic property as a fine modulator of inflammation and atherogenesis.

关键词：动脉粥样硬化 C-反应蛋白构象氧化还原平衡化调 CRP 心血管疾病 C反应蛋白

哺乳动物毛色形成过程及黑色素细胞标志物研究进展

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饲料研究 2024年第8期47卷 165-169页

作者：刘小禹王国文舒适彭巍付长其徐尚荣黄荣张君青海大学畜牧兽医科学院青海西宁810016

哺乳动物的毛色主要由黑色素细胞合成的黑色素决定。细胞着色过程包括黑色素细胞的发育、黑色素的合成与代谢及调节黑色素合成的信号通路等。黑色素细胞可被区分为多种类型,且这些类型可用多种黑色素细胞标志物来鉴定。毛色可以判断动... 详细信息

哺乳动物的毛色主要由黑色素细胞合成的黑色素决定。细胞着色过程包括黑色素细胞的发育、黑色素的合成与代谢及调节黑色素合成的信号通路等。黑色素细胞可被区分为多种类型,且这些类型可用多种黑色素细胞标志物来鉴定。毛色可以判断动物的身体状况和营养状况,并且毛色不同可能会对动物生产产生一定影响。文章综述了哺乳动物毛色形成的结构基础及其发育周期,描述了从神经嵴到驻留在几种组织中的成熟黑色素细胞的细胞色素化过程,总结了黑色素细胞的类型及各个类型黑色素细胞的标志物,讨论了动物毛色在动物生产中的应用,为解析哺乳动物毛色形成遗传机制提供帮助及为毛色影响的动物生产提供有效建议。

关键词：哺乳动物毛色细胞色素化黑色素细胞标志物

维普期刊数据库博看期刊

Near-infrared absorbing(>700 nm)aza-BODIPYs by freezing the rotation of the aryl groups

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Chinese Chemical Letters 2022年第1期33卷 115-122页

作者： Yanyan Wang Dongxiang Zhang Kangming Xiong rong shang Xin-Dong Jiang Shenyang Key Laboratory of Functional Dye and Pigment Shenyang University of Chemical TechnologyShenyang 110142China CAS Key Laboratory of Separation Science for Analytical Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Department of Chemistry Graduate School of ScienceHiroshima UniversityHigashi-Hiroshima 7398526Japan

The typical aza-BODIPYs in the dye family are known for bright fluorescence,excellent stability,and tunable absorption ***,these dyes are attracting the increasing ***-BODIPYs having the maxima absorption in the near-infrared(NIR)region(650-900 nm)are very favorable for bioimaging in vivo due to the less photo-damage,deeper tissue penetration,and less interference from background auto-fluorescence by biomolecules in the living *** strategies have been employed to modify the structures of the aza-BODIPY core to provide the NIR absorbing *** these,the most effective method is the fusion of the aromatic rings in aza-BODIPY *** review allsidedly summarizes the recent development of ring-fused aza-BODIPY dyes(λ_(abs)>700 nm)focusing on the design,synthesis,and potential applications in the NIR region since 2002.

关键词： Aza-BODIPY NIR Ring-fused Red shift Freezing rotation

“长掘长探”技术在TBM掘进巷道中的应用研究

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煤炭技术 2024年第5期43卷 137-141页

作者：孙昊达王毅张杰白刚尚荣中煤科工西安研究院(集团)有限公司西安710077

针对韩城矿区所属煤矿普遍存在奥灰含水层积水、小窑积水等水害隐患对TBM掘进巷道安全构成严重威胁的情况,迫切需要一种适用于TBM掘进工程的新型水害超前探查技术。结合矿区实际情况,提出了一种适用于煤矿井下TBM掘进巷道的水害探查技... 详细信息

针对韩城矿区所属煤矿普遍存在奥灰含水层积水、小窑积水等水害隐患对TBM掘进巷道安全构成严重威胁的情况,迫切需要一种适用于TBM掘进工程的新型水害超前探查技术。结合矿区实际情况,提出了一种适用于煤矿井下TBM掘进巷道的水害探查技术即“长掘长探”新技术。该技术将煤矿井下定向长钻孔钻进技术和井下孔内瞬变电磁技术进行有机地结合,分别对分支孔成孔技术和数据重构技术进行技术改良,通过优选工程技术方案,选取适配的设备及钻具,使用新型孔内瞬变电磁探测仪器,有效解决了韩城矿区TBM掘进巷道无法“随掘随探”的煤矿井下超前水害隐患探查技术难题,提高了巷道快速掘进地质超前的探测效率和成果精度。应用证明,该技术探测成功率高达95.11%,掩护成功率可达91.53%,同时节约了24%的工期,探得一处富水异常区误差最大仅有0.3 m,该技术适合在类似矿井巷道掘进中推广应用。

关键词：超前水害探查煤矿掘进巷道长掘长探定向长钻孔孔内瞬变电磁

Development of aryl-containing dipyrrolyldiketone difluoroboron complexes(BONEPYs):Tune the hydrogen bond o-C—H…F for fluoride recognition

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Chinese Chemical Letters 2020年第5期31卷 1317-1321页

作者： Xin-Dong Jiang Zhumei Shao Changliang Sun Shuai Yue rong shang Yohsuke Yamamoto College of Applied Chemistry Shenyang University of Chemical TechnologyShenyang 110142China Department of Chemistry Graduate School of ScienceHiroshima UniversityHigashi-Hiroshima 739-8526Japan

Dipyrrolyldiketone difluoroboron complexes(BONEPYs)were synthesized by condensation of the corresponding pyrroles and malonyl chloride followed by treatment with BF3·*** aryl-substituted pyrrole is introduced to form a cyclic system in order to investigate anion binding *** BONEPYs 1-3 the o-H of the aryl group forms hydrogen bonding with F to give a more table *** contrast,the intramolecular hydrogen-bonded BONEPY endo-4 is more stable than its exo *** adding F,the hydrogen bonds must be broken first to give 4·(3)*** to the electron-rich group(-OMe),the o-H of the phenyl group can hardly interact with F via hydrogen bonding to give the less stable complex4-(5)*** energy diffe rences between the different conformations were calculated using DFT methods,which is consistent to the experimental observations.

关键词： BONEPY Hydrogen bond Fluorescent dye Fluoride anion Probe

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煤气化工厂总平面布置设计要点分析

大氮肥 2024年第1期47卷 6-9,17页

作者：马鑫豪李晚璐尚荣李雅晴中国联合工程有限公司浙江杭州310051

基于煤气化工厂典型工艺装置和公辅设施的生产特点,从厂址选择、集约用地、安全环保和提高企业效益的角度出发,讨论煤气化工厂总平面布置的设计要点,并归纳总结,旨在提升设计质量,规避设计误区。

关键词：煤气化工厂厂址选择总平面布置集约用地

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降低轧机支承辊油膜润滑油含水量方法的研究

冶金设备管理与维修 2024年第1期42卷 12-13页

作者：崔光耀高健商融张凤亮鞍钢股份有限公司冷轧厂辽宁鞍山114000

以酸轧联合机组轧机支承辊油膜润滑系统为研究对象,以降低在线油膜润滑油含水量为任务目标,综合分析现场油膜润滑系统进水原因,研究一种方便易行的能够降低油膜油含水量的操作方法,既能为轧辊轴承提供良好的润滑保障,又能解决润滑油长... 详细信息

以酸轧联合机组轧机支承辊油膜润滑系统为研究对象,以降低在线油膜润滑油含水量为任务目标,综合分析现场油膜润滑系统进水原因,研究一种方便易行的能够降低油膜油含水量的操作方法,既能为轧辊轴承提供良好的润滑保障,又能解决润滑油长期含水量居高不下的问题,延长润滑油使用寿命,减少碳排放,实现降本增效及环保生产。

关键词：轧机轧辊油膜油含水量