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Asymmetric Electrophilic α-Cyanation Reactions

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Asymmetric Electrophilic α-Cyanation Reactions

The Development of the Electrophilic α-Cyanation Reactions

中国化学会第八届全国分子手性学术研讨会

作者： Fu-Xue Chen hong-quan yin School of Chemistry & Chemical Engineering Beijing Institute of Tehcnology

Cyano is of great importance in natural compounds and biologically active molecules in pharmaceuticals and agricultural chemicals as well as its divers transformations to other functional *** virtually developed nucleophilic additions of cyanide to varying substrates bearing an sp2 prochiral moiety,the directly catalytic enantioselective formation of C(sp)-CN bond remains *** in 2015,we found the hypervalent iodine cyano reagent 1 serving as a very good cationic cyano source thus achieving the readily synthesis of racemic α-cyano β-keto ester/amine products without additional catalyst in DMF *** the mild reactivity of 4-acetylphenyl cyanate 2,it was employed as the electrophilic cyano reagent to develop a highly enantioselective cyanation of cyclic β-keto carbonyls by Lewis acid *** in substrate,a series of all-carbon quaternary 3-aryl-3-cyano oxindoles were synthesized using a Zinc complex of a chiral pincer ligand as the catalyst in high yields and excellent enantioselectivities for the first time in our *** the same cyano reagent,much sluggish amide substrate also accomplished the α-cyanation using organocatalysis.

关键词： asymmetric catalysis nitrile α-cyanation electrophilic substitution enantioselectivity

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The Development of the Electrophilic α-Cyanation Reactions

高效液相色谱法测定甲氰咪胍氯化钠注射液的含量

中国化学会第十四届全国有机合成化学学术研讨会

作者： Jia-Shen Qiu Pran Gopal Karmaker Di Wu hong-quan yin Fu-Xue Chen School of Chemistry & Chemical Engineering Beijing Institute of Technology

Cyano exists extensively in natural compounds and biologically active molecules as a result of its fascinating bioactivity, together with its compelling transformations to divers functional groups. Despite virtually developed nucleophilic addition reactions of cyanide to varying substrates bearing an sp prochiral moiety such as C=C, C=O, and C=N double bonds, the directly catalytic enantioselective introduction of cyano group to the sp carbon chain remains challenging. Early in 2015, we firstly found the hypervalent iodine cyano reagent 1 serving as a very good cationic cyano source thus readily achieving the racemic α-cyanation of β-keto ester/amine without additional catalyst in DMF promptly. Considering the tuneable reactivity of cyanates, 4-acetylphenyl cyanate(2) was employed as the electrophilic cyano reagent to develop a highly enantioselective α-cyanation of cyclic β-keto carbonyls by Lewis acid catalysis. Using the same reagent, a series of all-carbon quaternary 3-aryl-3-cyano oxindoles were synthesized by a Zinc complex of a chiral pincer ligand as the catalyst in high yields and excellent enantioselectivities for the first time in our group.

关键词： asymmetric catalysis α-cyanation enantioselectivity nitriles electrophilic substitution

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时珍国医国药 2006年第5期17卷 726-727页

作者：全红梅尹秀梅张学武延边大学药学院延边大学药学院吉林延吉133000

目的建立高效液相色谱(HPLC)法测定甲氰咪胍氯化钠注射液的含量。方法分析柱为ODSC18(4.6 mm×200mm,5μm);流动相为甲醇-磷酸盐缓冲液(30∶70);检测波长218 nm。结果甲氰咪胍氯化钠注射液的线性范围为6.4~19.2μg/m l(r=1.000 0),平均... 详细信息

目的建立高效液相色谱(HPLC)法测定甲氰咪胍氯化钠注射液的含量。方法分析柱为ODSC18(4.6 mm×200mm,5μm);流动相为甲醇-磷酸盐缓冲液(30∶70);检测波长218 nm。结果甲氰咪胍氯化钠注射液的线性范围为6.4~19.2μg/m l(r=1.000 0),平均回收率为99.76%,RSD为0.49%(n=9)。结论该方法简便、准确、重现性好,能够满足西咪替丁的药品质量监控。

关键词：甲氰咪胍含量测定高效液相色谱法

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低浓度煤层气液化技术及其应用

天然气工业 2008年第3期28卷 117-120页

作者：范庆虎李红艳尹全森杨光达贾林祥哈尔滨工业大学低温与超导技术研究所

针对大庆庆深煤层气气源条件,提出采用液化精馏的方法处理含有大量氮氧的低浓度煤层气,生产LNG。定义了适用于低浓度煤层气液化系统的煤层气气源中甲烷摩尔分数为30%～87%;该方法中的净化单元采用MEA溶液化学吸收酸性气体,液化单元采用... 详细信息

针对大庆庆深煤层气气源条件,提出采用液化精馏的方法处理含有大量氮氧的低浓度煤层气,生产LNG。定义了适用于低浓度煤层气液化系统的煤层气气源中甲烷摩尔分数为30%～87%;该方法中的净化单元采用MEA溶液化学吸收酸性气体,液化单元采用具有高效率的混合工质制冷剂液化流程,低温部分采用精馏塔脱除氮氧组分提高LNG中甲烷含量;运用大型数值分析软件对液化系统进行了模拟计算与比较分析,分析了混合制冷剂中CH4、C2H6、C4H10及N2等组分对液化单元换热器内部最小温差的影响。分析结果显示:合理的制冷工质配比能够有效地降低换热温差,减少不可逆损失,提高换热效率。LNG中的含氧量随着精馏塔理论塔板数的增加而降低,但精馏塔的高度相应地增加。因此,应适当增加理论板数以有效地提高LNG中甲烷的浓度。计算结果将有助于低浓度煤层气液化装置的国产化应用与推广。

关键词：低浓度煤层气液化技术应用低温分离

STUDY FOR STREAMLINE OF ARBITRARY SHAPED HOMOGENEOUS RESERVOIRS WITH IMPERMEABLE BARRIERS

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Journal of Hydrodynamics 2006年第3期18卷 329-333页

作者： yin hong-jun FU Chun-quan HE ying-fu Key Laboratory of Enhanced Oil and Gas Recovery of Ministry of Education Daqing 163318 China Institute of Porous Flow and Fluid Mechanics CNPC and CAS Langfang 065007 China

The steady-state flow mathematical model of arbitrary shaped homogeneous reservoirs with impermeable barrier is constructed in this paper. By using Boundary Element Method （BEM）, the mathematical model is solved. And a streamline generating technique is presented. The figures of streamlines are plotted and analyzed considering the effect of complex boundary and impermeable barriers. Through analyzing it indicates that the size, shape and orientation of impermeable barriers have various degree of influence on the streamlines. So, if there are impermeable barriers in reservoir according to the geological materials, the influence of impermeable barriers must be considered when adjusting flood pattern and injection strategy.

关键词： Boundary Element Method (BEM) streamline,impermeable barrier mathematical model pressure

NUMERICAL SIMULATIONS OF VISCOELASTIC FLOWS THROUGH ONE SLOT CHANNEL

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Journal of Hydrodynamics 2007年第2期19卷 210-216页

作者： yin hong-jun Zhong Hui-ying FU Chun-quan WANG Lei Key Laboratory of Enhanced Oil and Gas Recovery of Ministry of Education Daqing Petroleum Institute Daqing 163318 China Oil Recovery Plant No. 1 Daqing Oilfield Corp. Ltd. Daqing 163001 China

In this article, the Modified Upper-Convected Maxwell equation （MUCM） is proposed. The viscoelastic polymer solution flow characteristics are described by the numerical method. The stream function contour, velocity contour and stress modulus contour of fluid in slot channel are drawn. The non-Newtonian power law property and viscoelasticity of MUCM fluid influence on the stream function are analyzed. The velocity contour move towards dead oil area with the viscoelasticity increase, flow area increase and the sweep area enlarges, so the sweep efficiency is enhanced.

关键词： viscoelastic fluid Modified Upper-ConvectedMaxwell (MUCM) constitutive equation power law exponent,Weissenberg number

Prediction model for flow stress during isothermal compression in α+β phase field of TC4 alloy

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Rare Metals 2018年第5期37卷 369-375页

作者： Shun Yang hong Li Jiao Luo yin-Gang Liu Miao-quan Li School of Materials Science and Engineering Northwestern Polytechnical University

Isothermal compression of TC4 alloy was performed on a Thermecmaster-Z simulator at the deformation temperatures ranging from 1093 to 1243 K, the strain rates ranging from 0.001 to 10.000 s^-l and a maximum strain of 0.8. The experimental results show that the flow stress increases with the decrease in the deformation temperature and the increase in the strain rate. The apparent activation energy for deformation is much lower at lower strain rates than that at higher strain rates. The flow stress model considering strain compensation was established. The average relative error between the calculated flow stress and experimental results is about 7.69%, indicating that the present model could be used to accurately predict the flow stress during high temperature in α＋β phase field of TC4 alloy.

关键词： TC4 alloy Isothermal compression Model Flow stress

Effects of Phase Composition on Microstructure and Mechanical Properties of Lu_2O_3-doped Porous Silicon Nitride Ceramics

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Journal of Materials Science & Technology 2011年第6期27卷 529-533页

作者： quan Li Xiaowei yin National Key Laboratory of Thermostructure Composite Materials Northwestern Polytechnical University Xi'an 710072 China

Porous silicon nitride ceramics（Si3N4） were fabricated by pressureless sintering using different particle size of silicon nitride ***2O3 was used as sintering *** to phase relationships in the ternary system Si3N4-SiO2-Lu2O3,porous Si3N4 ceramics with different phase composition were designed through the change of the content of SiO2 which was formed by the oxidation at 800℃ in *** Si3N4 with different phase compositions was obtained after sintering at 1800℃ in N2atmosphere.A small content of SiO2 favored the formation of secondary phase Lu4Si2O7N2,while large content of SiO2 favored the formation of secondary phase Lu2Si2O7 and *** Si3N4 ceramics with secondary phase Lu4Si2O7N2 had a flexural strength of 207 MPa,while that with secondary phase Si2N2O and Lu2Si2O7 had lower flexural strength.

关键词： Porous silicon nitride ceramics Secondary phase SiO2

Metagenomic next-generation sequencing may assist diagnosis of osteomyelitis caused by Mycobacterium houstonense:A case report

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World Journal of Orthopedics 2024年第11期15卷 1095-1100页

作者： hong-yin Lin quan-Hui Tan Department of Infectious Disease Shanghai Sixth People's HospitalShanghai 200233China

BACKGROUND Mycobacterium houstonense(***)belongs to the nontuberculous mycobacterium *** caused by *** is prone to *** SUMMARY We present a patient who was diagnosed with osteomyelitis caused by *** and treated with a combination of cefoxitin,and amikacin combined with *** The emergence of metagenomic next-generation sequencing(NGS)has brought new hope for the diagnosis and treatment of listeria *** can analyze a large number of nucleic acid sequences in a short time and quickly determine the pathogen species in the *** with traditional cerebrospinal fluid culture,NGS can greatly shorten the diagnosis time and provide strong support for the timely treatment of *** treatment,NGS can also play an important *** and accurate diagnosis can enable patients to start targeted treatment as soon as possible and improve the treatment *** the same time,by monitoring the changes in pathogen resistance,the treatment plan can be adjusted in time to avoid treatment failure.

关键词： Mycobacterium houstonense Osteomyelitis Diagnosis Treatment Metagenomic next-generation sequencing Case report