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Chinese Chemical Letters 2018年第2期29卷 267-270页

作者： Hao-Yan Yin Juan Tang jun-long Zhang Beijing National Laboratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular Engineering Peking University

Targeted-delivery is of great importance to molecular probes and drugs for cell biology study. Herein we reported 11 sulfur-containing coumarins as cell imaging probes. Different sulfur speciation of the 4 representative coumarins SC1-SC4 renders them significantly different subcellular localizations and cellular uptake pathways： SC1 containing thioether group located in lysosomes, while sulfoxide and sulfone compounds SC2 and SC3 distributed in the whole cell. Furthermore, the cationic sulfonium containing compound SC4 was internalized by clathrin-mediated endocytosis and localized at mitochondria. By analyzing the molecular parameters of all 11 coumarins, we found that different sulfur speciation affected their lipophilicity and electrostatic surface potential. These two key factors play roles in altering biological behaviors of the coumarins. The results revealed the importance of sulfur speciation on the physicochemical properties and thus subcellular localization of bioprobes. This is useful for designing new functional bioprobes.

关键词： Fluorescent imaging Sulfur speciation Subcellular Iocalization Sulfonium Mitochondria targeting Electrostatic surface potential

Canonical Characteristic Relation for Two Dimensional Euler Equations

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Applied Mathematics(A Journal of Chinese Universities) 2011年第3期26卷 327-333页

作者： SUN Shun-kai SHEN long-jun ZHOU Yu-lin Institute of Applied Physics and Computational Mathematics Beijing B.O. Box 8009 P.R.China

We propose a new way of rewriting the two dimensional Euler equations and derive an original canonical characteristic relation based on the characteristic theory of hyperbolic systems. This relation contains the derivatives strictly along the bicharacteristic directions, and can be viewed as the 2D extension of the characteristic relation in 1D case.

关键词： Euler equations characteristic relation bicharacteristics hyperbolic system.

Fluid Catalytic Cracking Technology for Maximum Gasoline Production

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China Petroleum Processing & Petrochemical Technology 2021年第1期23卷 41-47页

作者： Yan Jiasong Yu Shanqing long jun Gong Jianhong Research Institute of Petroleum Processing SINOPECBeijing 100083

Increasing gasoline production in FCC unit can improve the utilization efficiency of petroleum resources and gain economic *** paper discusses the technical principles for increasing FCC gasoline yield from the aspects of feedstock properties,operating conditions,LCO(light cycle oil)recycling,catalyst selection and reactor type,and illustrates the industrial application examples for maximizing gasoline *** technical measures,such as optimizing the feedstock,properly increasing the catalyst activity and reaction temperature,recycling LCO or hydrotreated LCO,applying high gasoline yield catalyst,and adopting the two-zone riser reactor,are proposed to enhance the gasoline yield.

关键词： fluid catalytic cracking gasoline light cycle oil riser reactor

Getting a Sense of ATP in Real Time

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Neuroscience Bulletin 2022年第7期38卷 834-836页

作者： Anthony D.Umpierre Koichiro Haruwaka long-jun Wu Department of Neurology Mayo ClinicRochesterMN55905USA Department of Neuroscience Mayo ClinicJacksonvilFL32224USA Department of Immunology Mayo ClinicRochesterMN55905USA

Adenosine 5'-triphosphate(ATP)is a purinergic signal that can be sensed by all major cell classes in the *** is a key signal released during periods of physical damage/injury,inflammation,and neurological events,such as *** ATP signaling in the living brain is complicated by its fast enzymatic degradation,its action at multiple receptors,and its somewhat elusive.

关键词： signal damage somewhat

Mechanism Study of BF_(3)/n-Butanol-catalyzed 1-Decene Oligomerization Reaction

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China Petroleum Processing & Petrochemical Technology 2023年第2期25卷 74-80页

作者： He Leilei Su Shuo Zhao Yi Xu Bing long jun Sinopec Research Institute of Petroleum Processing Co. Ltd.Beijing 100083

The active catalysts of the BF_(3)/n-C_(4)H_(9)OH-catalyzed 1-decene oligomerization reaction,as well as the distribution of the reaction products,was investigated by molecular *** calculation results show that(BF_(3))_(2)·n-C_(4)H_(9)OH catalyzes the 1-decene oligomerization reaction with higher activity compared to BF_(3)·n-C_(4)H_(9)OH,which is the most catalytically active substance in the BF_(3)/n-C_(4)H_(9)OH catalyst *** reaction energy barriers and heats of reaction of chain initiation,chain growth,and chain termination in BF_(3)/n-C_(4)H_(9)OH-catalyzed 1-decene oligomerization are calculated to reveal the product *** calculation results show that the contents of the oligomerization reaction products in descending order are trimer,tetramer,pentamer,and *** calculated results were consistent with the experimentally obtained product distribution.

关键词： poly-α-olefin synthetic base oil oligomerization reaction reaction mechanism boron trifluoride

灵武白芨滩不同年限柠条固沙林林下草本群落演替规律及机制

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草业学报 2024年第3期33卷 13-23页

作者：于双李小伟王瑞霞杨君珑马龙宁夏大学林业与草业学院宁夏银川750021 宁夏大学西北土地退化与生态恢复省部共建国家重点实验室培养基地宁夏银川750021 宁夏灵武白芨滩国家级自然保护区管理局宁夏灵武750400

为探讨柠条固沙林林下草本群落演替序列与环境因子的关系,调查了灵武白芨滩不同种植年限(3、5、10、20、30、40、50、60和70年)柠条林下草本群落,测定了土壤理化性质,采用双向指示种分析(TWINSPAN)、除趋势对应分析(DCA)和冗余分析(RDA... 详细信息

为探讨柠条固沙林林下草本群落演替序列与环境因子的关系,调查了灵武白芨滩不同种植年限(3、5、10、20、30、40、50、60和70年)柠条林下草本群落,测定了土壤理化性质,采用双向指示种分析(TWINSPAN)、除趋势对应分析(DCA)和冗余分析(RDA)的方法对群落进行数量分类和排序,并分析群落演替序列与环境因子间的关系。结果表明:1)应用TWINSPAN将9个样地的27个样方划分为4个群落类型:蒙古虫实+沙蓬群落→沙鞭+白沙蒿群落→狗尾草+藜群落→猪毛蒿+短花针茅群落。2)DCA排序与TWINSPAN分类结果一致,DCA排序进一步印证了TWINSPAN分类的合理性。3)通过冗余分析(RDA)显示,土壤有机质含量和土壤pH值是影响林下草本植物群落演替的主要环境因子,解释量分别为19.3%和13.6%,贡献率分别达37.5%和26.5%(P<0.05)。本研究对揭示白芨滩固沙林林下草本群落演替规律和驱动因素具有重要意义,结果可为荒漠化治理及白芨滩自然保护区的科学管理提供理论依据。

关键词：白芨滩自然保护区林下植被排序演替序列环境因子

基于3D金属打印技术锁骨近端解剖钢板的数字化研究

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中国骨伤 2024年第3期37卷 278-280页

作者：郑轶郑兴国张嘉锴吴君龙袁欣华中国科学院大学宁波华美医院骨科浙江宁波315010

目的:探讨3D金属打印技术结合虚拟设计锁骨近端解剖钢板的可行性。方法:回顾性选择1例52岁男性健康志愿者,运用Mimics15.01,NX12.0等软件设计锁骨近端解剖钢板系统,将STL数据输入3D打印机打印1∶1锁骨模型及锁骨近端解剖钢板,并在体外... 详细信息

目的:探讨3D金属打印技术结合虚拟设计锁骨近端解剖钢板的可行性。方法:回顾性选择1例52岁男性健康志愿者,运用Mimics15.01,NX12.0等软件设计锁骨近端解剖钢板系统,将STL数据输入3D打印机打印1∶1锁骨模型及锁骨近端解剖钢板,并在体外试验钢板的贴合性和影像学评估螺钉位置的准确性,记录模型的打印时间、钉道设计及锁骨近端解剖钢板制作时间。结果:3D金属打印锁骨近端解剖钢板与锁骨模型贴合良好,锁骨近端锁定螺钉的导向准确,X线及CT扫描显示螺钉位置良好。模型打印时间、钉道设计及锁骨近端解剖钢板制作的时间分别为120、15和300 min。结论:基于3D金属打印技术锁骨近端解剖钢板系统可实现锁骨近端骨折钢板的良好贴合和螺钉精确置入,为锁骨近端骨折的治疗方案提供一种新的精确手术方法。

关键词： 3D金属打印个体化锁骨近端钢板

Synergetic Effect of Y Zeolite and ZSM-5 Zeolite Ratios on Cracking, Oligomerization and Hydrogen Transfer Reactions

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China Petroleum Processing & Petrochemical Technology 2014年第3期16卷 1-9页

作者： Gong Jianhong Xu Youhao long jun Wei Xiaoli SINOPEC Research Institute of Petroleum Processing

The objective of this study is to explore the optimum composition of Y and ZSM-5 zeolites to develop novel catalysts for obtaining lower gasoline olefins content and higher propylene yield. Five composite zeolite catalysts with varying Y zeolite/ZSM-5 zeolite ratios have been prepared in this work to investigate the synergy between the Y zeolite and ZSM-5 zeolite on the selectivity to protolytic cracking, β-scission, oligomerization, and hydrogen transfer reactions using a FCC naphtha feedstock at 480 ℃ in a confined fluidized bed reactor. Experimental results showed that the composite catalyst with a Y zeolite/ZSM-5 zeolite ratio of 1:4 had the highest protolytic cracking and β-scission ability, which was even higher than that of pure ZSM-5 catalyst. On the other hand, the catalyst with a Y zeolite/ZSM-5 zeolite ratio of 3:2 exhibited the strongest hydrogen transfer functionality while the pure Y zeolite based catalyst had the highest oligomerization ability. For all the catalysts tested, increasing conversion enhanced the selectivity to protolytic cracking and hydrogen transfer reactions but reduced the selectivity to β-scission reaction. However, no clear trend was identified for the selectivity to oligomerization when an increased conversion was experienced.

关键词： composite zeolites protolytic cracking β-scission oligomerization hydrogen transfer

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盐渍土既有高速铁路路基压实质量检测

高速铁路技术 2024年第2期15卷 45-49页

作者：胡超张健陈伟志龙军中铁二院工程集团有限责任公司成都610031

高速铁路路基填料压实标准主要通过压实系数、地基系数、动态变形模量等指标进行控制。对于既有路基,在不破坏路基的条件下,路基内部的控制指标难以有效测试。为评价某海外项目既有路基内部填料压实情况,最大程度减少对既有路基工程的... 详细信息

高速铁路路基填料压实标准主要通过压实系数、地基系数、动态变形模量等指标进行控制。对于既有路基,在不破坏路基的条件下,路基内部的控制指标难以有效测试。为评价某海外项目既有路基内部填料压实情况,最大程度减少对既有路基工程的扰动破坏,通过试验段建立了动力触探试验(DPT)锤击数与实测压实系数、地基系数、动态变形模量的拟合关系式,并将其应用于该项目全线路基内部压实质量检测。结果表明:应用该拟合关系式能够避免对既有路基的破坏,节约工期,取得了较好的经济效益。

关键词：盐渍土既有高速铁路路基工程压实质量无损检测

Optimization of three-loop missile autopilot gain under crossover frequency constraint

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Defence Technology（防务技术） 2016年第1期12卷 32-38页

作者： M.A.ABD-ELATIF long-jun QIAN Yu-ming BO School of Automation University of Science and TechnologyNanjing

The open-loop crossover frequency is pointed as an important parameter for practical autopilot design. Since different gain designs may achieve the same open-loop crossover frequency, it should be neither considered as a performance objective of the optimal autopilot design-schemes nor neglected. Besides, the main assignment of the autopilot is to drive the missile to track the acceleration commands, so the autopilot gain design should be evaluated directly according to the resultant tracking performance. For this purpose, an optimal design methodology of the three-loop missile autopilot is introduced based on constraint optimization technique, where the tracking performance is established analytically as the design objective and the open-loop crossover frequency is formed as inequality constraint function, both are manipulated in terms of stable characteristic parameters of the autopilot closed-loop. The proposed technique is implemented with the assistance of a numerical optimization algorithm which automatically adjusts the design parameters. Finally, numerical simulation results are provided to demonstrate the effectiveness and feasibility of the proposed approach compared with that in some references.

关键词：导弹自动驾驶仪频率约束优化技术三回路增益设计方法跟踪性能数值模拟