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Theoretical studies on the mechanism of the thermal decarboxylation and decarbonylation of a number of α-keto-acids

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Chinese Journal of Chemistry 1995年第6期13卷 487-492页

作者： chen,Li-Tao chen,guang-Ju fu,Xiao-YuanChemistry Department,Beijing Normal University,Beijing 100875,China Chemistry Department Beijing Normal University Beijing 100875 China

Both processes of decarboxylation and decarbonylation of a number of acids including RCOCO2H,R=H,CH3,CH2F,CF3,CH=CH2,Ph,OH have been studied by semi-empirical MO theory AMI method to verify the reaction mechanism of each process and the effect of different substituents on *** calculated results are consistent with the experimental reports and can be summed up as follows:(1) The decarboxylation of these acids to form aldehydes and carbon dioxide is concerted and takes place through a 4-membered ring transition state in which a partial negative charge develops on the carbon of the α-carbonyl group,so that the inductive effect of some substituents is favourable for this process.(2) Their decarbonylation into carboxylic acids and carbon monoxide however is the attack of the OH on the carbon of the alkyl portion of the acid,forming a 3-membered ring transition state.(3) The activation energy of decarbonylation is lower than that of decarboxylation,since oxygen is more nucleophilic than hydrogen and also the strong OH bond need not to be broken.

关键词： Decarboxylation decarbonylation a-keto-acid

Ab initio studies on the pyrolysis mechanism of 2-haloacetic acids in the gas phase

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Chinese Journal of Chemistry 1995年第1期13卷 10-18页

作者： chen, Li-Tao chen, guang-Ju fu, Xiao-YuanChemistry Department, Beijing Normal University, Beijing 100875, China Chemistry Department Beijing Normal University Beijing 100875 China SU.EDU

The dehydrohalogenation mechanism of 2-haloacetic acids (XCH2CO2H, X=F, Cl and Br) has been studied theoretically by HF/3-21G and AM1 methods. The results indicate that these reactions are most probably proceeded in terms of a polar five-membered cyclic transition state in the gas phase. Their microscopic processes are beleived to be a stepwise reaction and the rate-determining step is the first one. By comparing the energy barriers of different 2-haloacetic acids, it can be realized that 2-fluoroacetic acid is easier to react than 2-chloroacetic and 2-bromoacetic acids.

关键词： 2-Haloacetic acid pyrolysis reaction mechanism transition state.

Financial Derivatives Market and Storage Management

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厦门大学学报（自然科学版） 2002年第S1期41卷 284-285页

作者： chen guang-fu, WANG Zhou-jing (Department of Automation, Xiamen University, Xiamen 361005, China)

It’s known to all that under ideal condition the s to rage cost is kept in lower level when storage management be arranged by Economic Order Quantity(EOQ).Does this mean that any companies should set up their own storing system in proportion to the scale of the commodities’ producing or sell ing furthermore, even if they manage storage in EOQ, because of different oper ation scale, geographical condition or ability borrowing money from financial ma rket, different companies pay unequal cost in storing the same *** thi s paper, except for supplying commodities from our own storage system, the autho rs have analyzed other two supplying ways without whole storage system, they are forward contracts and futures *** authors have discussed variable su pply cost for above different supply *** to the cost of each sup ply way, the managers can choose the most economical way in supplying the commod ity and predict the price of futures from storage management arranged by *** e summary content is as follow: 1. The comparing of supply cost between forward contracts and storing system a rranged by EOQ. (1) The supply cost from forward contracts (2) The supply cost from storage system arranged by Economic Order Quantity (3) The application example for comparing cost in different supply way *** comparing of supply cost between futures going physical and storing syst em arranged by Economic Order Quantity. (1) The supply cost from futures going physical (2) The correlation between futures contracts and storage management arranged b y EOQ (3) The application example for comparing cost in different supply way *** does storing system of scale economic affect the price of forward and fu tures contracts (1) How does the price of forward and futures contracts fluctuate (2) How do we calculate the price of a commodity at future point from the cost of scale economic storing (3) How do we operate efficiently in derivatives market by using the cost of s

关键词： Economic Order Quantity forward contracts futur es contracts storage management financial derivatives market

Synthesis and thermoelectric properties of Rashba semiconductor BiTeBr with intensive texture

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Rare Metals 2018年第4期37卷 274-281页

作者： Jia-Zhan Xin chen-guang fu Wu-Jun Shi Guo-Wei Li Gudrun Auffermann Yan-Peng Qi Tie-Jun Zhu Xin-Bing Zhao Claudia Felser Max Planck Institute for Chemical Physics of Solids 01187 Dresden Germany State Key Laboratory of Silicon Materials School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027 China School of Physical Science and Technology ShanghaiTech University Shanghai 200031 China

Bismuth tellurohalides with Rashba-type spin splitting exhibit unique Fermi surface topology and are developed as promising thermoelectric materials. However, BiTeBr, which belongs to this class of materials, is rarely investigated in terms of the thermoelectric transport properties. In the study, polycrystalline bulk BiTeBr with intensive texture was synthesized via spark plasma sintering （SPS）. Additionally, its thermoelectric properties above room temperature were investigated along both the inplane and out-plane directions, and they exhibit strong anisotropy. Low sound velocity along two directions is found and contributes to its low lattice thermal conductivity. Polycrystalline BiTeBr exhibits relatively good thermoelectric performance along the in-plane direction, with a maximum dimensionless figure of merit （ZT） of 0.35 at 560 K. further enhancements of ZT are expected by utilizing systematic optimization strategies.

关键词： Bismuth tellurohalides BiTeBr Thermoelectric properties Texture

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大型施工企业的技术管理

中国港湾建设 2006年第1期26卷 70-73页

作者：陈光福第二航务工程局湖北武汉430014

施工企业的技术管理是生产经营管理的重要组成部分,它的优劣体现施工企业的生命力和竞争能力的强弱。笔者以40余年的施工经历,介绍技术管理在施工中的职能和要点。

关键词：施工技术管理

右美托咪定对颅内肿瘤手术患者血流动力学的影响及脑保护作用

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临床麻醉学杂志 2015年第1期31卷 15-17页

作者：陈晓梅陈广福福建省福州市第二医院麻醉科 350007

目的探讨右美托咪定对颅内肿瘤手术患者血流动力学的影响及对患者脑保护的作用。方法将60例择期行颅内肿瘤手术患者随机分为右美托咪定组和对照组,每组30例。右美托咪定组患者诱导后静脉注射右美托咪定1μg/kg,10min注射完毕,术中持续... 详细信息

目的探讨右美托咪定对颅内肿瘤手术患者血流动力学的影响及对患者脑保护的作用。方法将60例择期行颅内肿瘤手术患者随机分为右美托咪定组和对照组,每组30例。右美托咪定组患者诱导后静脉注射右美托咪定1μg/kg,10min注射完毕,术中持续静脉泵注右美托咪定0.4μg·kg^-1·h^-1。对照组诱导后给予等量生理盐水。记录两组患者入室后（T0）、给药后（T1）、插管时（T2）、苏醒时（T3）、拔管时（T4）、出手术室（T5）的SBP、DBP、MAP及HR。并检测T0、手术完成（T6）、术后6h（T7）、术后12h（T8）和术后24h（T9）的血清S100β和NSE水平。结果与对照组比较,右美托咪定组T1～T5时SBP、DBP和MAP明显降低,HR明显减慢（P〈0.05）。与T0时比较,右美托咪定组T1～T5点MAP水平明显降低（P〈0.05）。与T0时比较,两组T6～T9时S100β和NSE水平明显增高（P〈0.05）。与对照组比较,右美托咪定组T6～T9时血清S100β和NSE水平明显降低（P〈0.05）。结论右美托咪定可较好维持颅内肿瘤患者术中血流动力学的稳定,术中、术后24h内S100β和NSE水平较低。

关键词：右美托咪定颅内肿瘤血流动力学脑保护

Application requirements and design strategies of Bi_(2)Te_(3)-based thermoelectric devices for low-quality thermal energy

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cMat 2024年第1期1卷 22-42页

作者： Kai Liu Yu-Zheng Li Yun-Xiao Wu Ping-Jun Ying Ran He chen-guang fu Yu Zhang Tie-Jun Zhu State Key Laboratory of Silicon and Advanced Semiconductor Materials and School of Materials Science and EngineeringZhejiang UniversityHangzhouChina Institute of Advanced Technology Zhejiang UniversityHangzhouChina Leibniz Institute for Solid State and Materials Research DresdenGermany Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering TaiyuanChina Institute of Wenzhou Zhejiang UniversityWenzhouChina

Bismuth telluride-based devices are capable of converting low-quality thermal energy into electrical power via the Seebeck *** transformative process not only extends the spectrum of energy utilization but also significantly amplifies energy *** review serves as a comprehensive guide,elucidating the intricate design considerations essential for optimizing bismuth telluride-based devices in both electrical and structural *** exploring various application scenarios,it identifies critical parameters crucial for device ***,the current landscape of thermoelectric(TE)devices is meticulously analyzed,synthesizing their developmental trajectory and contrasting it with stringent design *** this comprehensive analysis,it pinpoints key challenges that impede the maximal performance of existing TE *** the trajectory of bismuth telluride-based TE materials,this review makes projections regarding their future application *** through contemporary mechanisms and technologies,it offers practical solutions and po-tential avenues aimed at enhancing the efficiency of TE ***,this discourse endeavors to provide invaluable insights,furnishing a roadmap for the advancement and refinement of TE devices in the years *** proposing feasible solutions and charting plausible directions,it aspires to stimulate inno-vation and drive transformative progress in the domain of TE materials and science.

关键词： bismuth telluride Internet of Things radioisotope thermoelectric generator thermoelectric device wearable electronics

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21世纪重点理工大学艺术教育的作用与地位

艺术百家 2007年第2期23卷 145-147页

作者：原松梅陈复光哈尔滨工业大学黑龙江哈尔滨150001

21世纪是一个知识经济时代,社会经济、文化的发展,对教育、对人才都提出了新的要求。如何培养主动适应时代需要、人文精神与科学素养统一的高质量人才,是重点理工大学面临的一个重要课题,而加强艺术教育是提高人的综合素质,培养复合型... 详细信息

21世纪是一个知识经济时代,社会经济、文化的发展,对教育、对人才都提出了新的要求。如何培养主动适应时代需要、人文精神与科学素养统一的高质量人才,是重点理工大学面临的一个重要课题,而加强艺术教育是提高人的综合素质,培养复合型人才的重要途径。本文从新世纪人才需求变化的角度,通过对科学与艺术关系的分析,探讨了重点理工大学艺术教育的作用及对策。

关键词：重点理工大学艺术教育科学教育

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老年人急性脑血管病并发肺炎临床分析

中华老年医学杂志 1989年第1期8卷 43-44页

作者：陈光福汤先镗新疆石河子市人民医院内科

报道118例老年人急性脑血管病并发肺炎40例，并与同期115例非老年患者进行对照。老年组118例，并发肺炎40例（33.9%）；非老年组115例，并发肺炎20例（17.4%）。老年组并发肺炎患者均相继伴有一个或两个以上其它脏器的损害或衰竭，其中... 详细信息

报道118例老年人急性脑血管病并发肺炎40例，并与同期115例非老年患者进行对照。老年组118例，并发肺炎40例（33.9%）；非老年组115例，并发肺炎20例（17.4%）。老年组并发肺炎患者均相继伴有一个或两个以上其它脏器的损害或衰竭，其中肺炎加肾功能不全14例（35%），肺炎加消化道出血5例（12.5%），肺炎加心衰14例（35%），肺炎加肾功能不全加消化道出血6例（15%）。并发肺炎的40例老年患者死亡26例，病死率为65%。

关键词：脑血管病肺炎并发症老年人