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1,2-二甲基咪唑啉的合成及表征

有机化学 2009年第5期29卷 802-805页

作者：徐文清聂万丽 borzov maxim v. 马兵锋西北大学化学系西安710069 国立莫斯科大学化学系莫斯科119992

对1,2-二甲基咪唑啉的合成进行了详细研究.以甲胺水溶液和2-溴乙胺氢溴酸盐(1)为原料进行反应,在两种原料物质的量之比为5∶1,缓缓回流12h的条件下,得到N-甲基乙二胺(2),N-甲基乙二胺经过乙酸化得到N-甲基-N,N′-二乙酰基乙二胺(3),然后... 详细信息

对1,2-二甲基咪唑啉的合成进行了详细研究.以甲胺水溶液和2-溴乙胺氢溴酸盐(1)为原料进行反应,在两种原料物质的量之比为5∶1,缓缓回流12h的条件下,得到N-甲基乙二胺(2),N-甲基乙二胺经过乙酸化得到N-甲基-N,N′-二乙酰基乙二胺(3),然后,N-甲基-N,N′-二乙酰基乙二胺和氧化钙在高温下关环得到1,2-二甲基咪唑啉(4).并对所得到的产物1,2-二甲基咪唑啉经元素分析,1HNMR,IR和GC-MS得到了表征.

关键词： N-甲基-N,N′-二乙酰基乙二胺成环反应 1,2-二甲基咪唑啉水解

Re-inv.stigation of the Double Lithiation of Stannocene

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Re-investigation of the Double Lithiation of Stannocene

中国化学会第四届有机化学学术会议

作者： borzov maxim v. Krut’ko Dmitrii P． Department of Chemistry Moscow State UniversityLeninskie Gory 1bldng. 3Moscow 119992Russian Federation Department of ChemistryNorthwest University Xi’an 710069 Department of Chemistry Moscow State University Leninskie Gory 1bldng.3Moscow 119992Russian Federation

＜正＞Among the properties of stannocene [biscyclopentadienyltin（Ⅲ）] its ability to undergo double lithiation was reported. This rather intriguing adv.ntage, howev.r, has nev.r been applied in practice, except to perform the silylation and ev.n stepwise double silylation reactions. Nev.rtheless, since 1983 （LiC5H4）2Sn has been mentioned in related rev.ews and dictionaries of organometallic compounds.

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硅烷阳离子活性研究进展

化学通报 2013年第9期76卷 786-790页

作者：聂万丽刘敏霞 maxim v.borzov 乐山师范学院化学学院生物有机与表面科学重点实验室乐山614000 西北大学化学与材料科学学院合成与天然功能分子化学教育部重点实验室西安710069

硅烷阳离子具有独特的三价特征及高的亲电性和路易斯酸性,近年来其在有机合成中的应用受到广泛关注。本文主要从结构特征和反应活性两方面对硅烷阳离子进行了总结。对其稳定的结构类型、在CO2的活化及转化中的应用、催化C—F键的活化(... 详细信息

硅烷阳离子具有独特的三价特征及高的亲电性和路易斯酸性,近年来其在有机合成中的应用受到广泛关注。本文主要从结构特征和反应活性两方面对硅烷阳离子进行了总结。对其稳定的结构类型、在CO2的活化及转化中的应用、催化C—F键的活化(氢化去氟反应)以及作为一种新型的路易斯酸在催化Diels-Alder反应中的优越反应性能四个方面进行了介绍。

关键词：三价硅阳离子 CO2的活化氢化去氟反应路易斯酸Diels—Alder反应

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烯烃聚合钯催化剂研究进展

化学通报 2012年第8期75卷 681-690页

作者：张呈平聂万丽 borzov maxim v 西北大学化学与材料科学学院合成与天然功能分子化学教育部重点实验室西安710069

综述了烯烃聚合钯催化剂的研究进展,烯烃聚合钯催化剂的配体类型有膦配体、氮配体、碳配体、氧配体、氮-氧配体、膦-氧配体、氮-膦配体等。与齐格勒-纳塔催化剂和茂金属催化剂相比,烯烃聚合钯催化剂具有高催化活性、单活性中心和良好的... 详细信息

综述了烯烃聚合钯催化剂的研究进展,烯烃聚合钯催化剂的配体类型有膦配体、氮配体、碳配体、氧配体、氮-氧配体、膦-氧配体、氮-膦配体等。与齐格勒-纳塔催化剂和茂金属催化剂相比,烯烃聚合钯催化剂具有高催化活性、单活性中心和良好的分子剪裁性等优点,可在分子层次上实现烯烃聚合的分子设计与组装;与铁、钴、镍等后过渡金属催化剂相比,烯烃聚合钯催化剂具有反应条件较温和、催化活性和立体选择性较高的优势。

关键词：钯催化剂后过渡金属催化剂烯烃聚合反应

Roots of the taxonomic impediment:Is the“integrativ.ness”a remedy?

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Integrativ. Zoology 2020年第1期15卷 2-15页

作者： maxim v.v.NARSKI Laboratory of Macroecology and Biogeography of Inv.rtebrates Saint-Petersburg State UniversitySaint-PetersburgRussia

The use of the“integrativ. approach”for classification of organisms since its formal establishment in 2005 has become a recurrent theme of zoosystematics.A bibliometric surv.y of the publications on integrativ. taxonomy of animals,which is aimed at exploring the most popular areas of research and characterizing the practical systematists’attitudes to this new approach,is *** analysis of 582 papers,which appeared between 2005 and 2017 in journals indexed by Scopus and the Web of Science Core Collection,has illustrated the gradual growth of the popularity of integrativ. taxonomy as well as some biases in the representation of higher taxa in“integrated”*** has been shown that the“integrativ.”papers hav. more chance of appearing in a top-ranking journal and gain relativ.ly more citations as compared with non-integrativ. *** obtained results are discussed in the context of the“taxonomic impediment”problem thought to be a consequence of the institutional crisis of traditional taxonomy,which has been v.v.dly debated ov.r the past decades.

关键词： animal systematics bibliometric analysis biodiv.rsity crisis integrativ. taxonomy taxonomic impediment

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两性离子催化剂的研究进展

化工进展 2013年第10期32卷 2396-2402页

作者：聂万丽曹蓉 maxim v.borzov 乐山师范学院化学学院四川乐山614000 西北大学化学与材料科学学院陕西西安710069

两性离子催化剂按照配体的结构特征和金属元素种类可分为两性离子茂金属配合物、非茂前过渡以及后过渡金属两性离子配合物三大类。两性离子茂金属配合物根据阴离子在配体上所连接区域的不同又可以分为Girdle型、Bridge型和Ring型三种。... 详细信息

两性离子催化剂按照配体的结构特征和金属元素种类可分为两性离子茂金属配合物、非茂前过渡以及后过渡金属两性离子配合物三大类。两性离子茂金属配合物根据阴离子在配体上所连接区域的不同又可以分为Girdle型、Bridge型和Ring型三种。本文对各类两性离子配合物的合成方法、结构特征和催化反应活性进行了归纳总结,发现两性离子催化剂对催化烯烃聚合表现出较好的活性,而非茂的两性离子配合物不仅是良好的烯烃聚合催化剂,还可以催化多种类型的小分子反应。作为一种新型高效的单组份活性催化剂,目前,有关两性离子催化剂的应用研究还有很多未知的领域有待开发,尤其是在小分子的活化、催化领域。

关键词：两性离子催化剂烯烃聚合茂金属配合物非茂金属配合物

A NUMERICAL METHOD FOR THE SIMULATION OF FREE SURFACE FLOWS OF v.SCOPLASTIC FLUID IN 3D

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Journal of Computational Mathematics 2011年第6期29卷 605-622页

作者： Kirill D. Nikitin maxim A. Olshanskii Kirill M. Terekhov.Yuri v. v.ssilev.ki Institute of Numerical Mathematics Russian Academy of Sciences Moscow Russia Department of Mechanics and Mathematics Moscow State University Moscow Russia

In this paper we study a numerical method for the simulation of free surface flows of v.scoplastic （Herschel-Bulkley） fluids. The approach is based on the lev.l set method for capturing the free surface ev.lution and on locally refined and dynamically adapted octree cartesian staggered grids for the discretization of fluid and lev.l set equations. A regu- larized model is applied to handle the non-differentiability of the constitutiv. relations. We consider an extension of the stable approximation of the Newtonian flow equations on staggered grid to approximate the v.scoplastic model and lev.l-set equations if the free boundary ev.lv.s and the mesh is dynamically refined or coarsened. The numerical method is first v.lidated for a Newtonian case. In this case, the conv.rgence of numerical solutions is observ.d towards experimental data when the mesh is refined. Further we compute sev.ral 3D v.scoplastic Herschel-Bulkley fluid flows ov.r incline planes for the dam-break problem. The qualitativ. comparison of numerical solutions is done v.rsus experimental inv.stigations. Another numerical example is giv.n by computing the freely oscillating v.scoplastic droplet, where the motion of fluid is driv.n by the surface tension forces. Altogether the considered techniques and algorithms （the lev.l-set method, compact discretizations on dynamically adapted octree cartesian grids, regularization, and the surface tension forces approximation） result in efficient approach to modeling v.scoplastic free-surface flows in possibly complex 3D geometries.

关键词： Free surface flows v.scoplastic fluid Adaptiv. mesh refinement Oetree meshes.

Learning surface molecular structures v.a machine v.sion

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npj Computational Materials 2017年第1期3卷 194-202页

作者： maxim Ziatdinov.Artem Maksov.Sergei v.Kalinin Institute for Functional Imaging of Materials Oak Ridge National LaboratoryOak RidgeTN 37831USA Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTN 37831USA Bredesen Center for Interdisciplinary Research University of TennesseeKnoxvilleTN 37996USA

Recent adv.nces in high resolution scanning transmission electron and scanning probe microscopies hav. allowed researchers to perform measurements of materials structural parameters and functional properties in real space with a picometre *** many technologically relev.nt atomic and/or molecular systems,howev.r,the information of interest is distributed spatially in a non-uniform manner and may hav. a complex multi-dimensional *** of the critical issues,therefore,lies in being able to accurately identify(‘read out’)all the indiv.dual building blocks in different atomic/molecular architectures,as well as more complex patterns that these blocks may form,on a scale of hundreds and thousands of indiv.dual atomic/molecular *** we employ machine v.sion to read and recognize complex molecular assemblies on ***,we combine Markov.random field model and conv.lutional neural networks to classify structural and rotational states of all indiv.dual building blocks in molecular assembly on the metallic surface v.sualized in high-resolution scanning tunneling microscopy *** show how the obtained full decoding of the system allows us to directly construct a pair density function—a centerpiece in analysis of disorderproperty relationship paradigm—as well as to analyze spatial correlations between multiple order parameters at the nanoscale,and elucidate reaction pathway inv.lv.ng molecular conformation *** method represents a significant shift in our way of analyzing atomic and/or molecular resolv.d microscopic images and can be applied to v.riety of other microscopic measurements of structural,electronic,and magnetic orders in different condensed matter systems.

关键词： allowed classify spatially

新型桥联单茂锆/MAO体系催化降冰片烯聚合研究

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化学试剂 2012年第8期34卷 688-690,693页

作者：王志军聂万丽 maxim v.borzov 西北大学化学与材料科学学院陕西西安710069

采用两种新型咪唑侧链官能化单茂锆{Ph2CN2C4H6CpZrCl3和PhCHN2C4H6CpZrCl3}与甲基铝氧烷(MAO)组成的催化体系进行降冰片烯的聚合,考察了不同温度、不同Al/Zr对催化效率的影响。得到了透明度高,能溶于有机溶剂,熔点高于400℃的聚降冰片... 详细信息

采用两种新型咪唑侧链官能化单茂锆{Ph2CN2C4H6CpZrCl3和PhCHN2C4H6CpZrCl3}与甲基铝氧烷(MAO)组成的催化体系进行降冰片烯的聚合,考察了不同温度、不同Al/Zr对催化效率的影响。得到了透明度高,能溶于有机溶剂,熔点高于400℃的聚降冰片烯。该催化体系在80℃、Al/Zr为500时催化活性最高,可达到104g PNBE/(molZr.h)。通过对聚合产物FTIR的分析,得到了不同条件下的主要聚合方式。

关键词：茂金属催化剂甲基铝氧烷降冰片烯聚合