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Selective Suspension in Aqueous Sodium Dodecyl Sulfate According to Electronic Structure type Allows Simple Separation of Metallic from Semiconducting Single-Walled Carbon Nanotubes

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Nano research 2009年第8期2卷 599-606页

作者： Kai Moshammer frank Hennrich Manfred M.Kappes forschungszentrum karlsruhe Institut für NanotechnologieD-76021 KarlsruheGermany institut für Physikalische chemie Universität KarlsruheD-76128 KarlsruheGermany

Both density gradient centrifugation and gel electrophoresis have been reported to allow high throughput separation of metallic from semiconducting single-walled carbon nanotubes(SWNts)when using aqueous sodium dodecyl sulphate(SDS)*** show here that both methods rely on an initial dispersion-by-sonication step,which is already selective with respect to electronic structure *** corresponding aqueous SDS“starting”suspensions obtained after sonication and purifi cation by simple centrifugation(70,000 g,1 h)contain semiconducting SWNts primarily in the form of small bundles whereas metallic SWNts are predominantly suspended as individual *** gradient centrifugation then separates the bundles from the individual tubes on the basis of differences in their overall buoyant *** electrophoresis separates the longer bundles from the shorter individual tubes on the basis of their different *** also demonstrate that such starting suspensions can be fractionated according to electronic structure type by even simpler techniques such as size exclusion chromatography or gel fi ltration,thus opening the way for simple scale-up.

关键词： Single-walled carbon nanotubes metallic–semiconducting separation electrophoresis density gradient centrifugation size exclusion chromatography

Sequence-sorted redox-switchable hetero[3]rotaxanes

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Organic Chemistry frontiers 2022年第1期9卷 64-74页

作者： Marius Gaedke Henrik Hupatz felix Witte Susanne M.rupf Clara Douglas Hendrik V.Schröder Lukas fischer Moritz Malischewski Beate Paulus Christoph A.Schalley institut für chemie und Biochemie der freien universität Berlin Arnimallee 2014195 BerlinGermany institut für chemie und Biochemie der freien universität Berlin Arnimallee 2214195 BerlinGermany institut für chemie und Biochemie der freien universität Berlin Fabeckstr.34/3614195 BerlinGermany

from a library of five crown ether macrocycles with different ring sizes and redox-active moieties,such as tetrathiafulvalene(ttf)and naphthalene dimiide(NDI),directional heterocircuit[3]rotaxanes were *** an axle with two binding sites with different steric accessibility,the concept of integrative self-sorting was applied to program the sequence of functional units in heteropseudo[3]*** on binding strength and ring size of the smaller macrocycles,different heteropseudo[3]rotaxane selectivities and stabilities were determined by 2D NMr spectroscopy and tandem mass spectrometry.A heteropseudo[3]rotaxane with rotaxane-like behaviour was isolated chromatographically,displaying electrochemically“frustrated”properties.A robust synthetic procedure was developed allowing the synthesis of four new hetero[3]rotaxanes incorporating specific sequences of functional *** pseudoisomeric rotaxanes which have the naphthalene diimide subunit at two different positions show distinct electrochemical *** calculations suggest that this differences could arise from a folding of the structure,in which the redox-active moieties stack with a stopper *** study presents a blueprint for the construction of hetero[3]rotaxanes with sequential control of the functional units along the track of the axle and paves the way to extend the functionality of mechanically interlocked molecules.

关键词： properties redox Sequence

Introduction of a reliable Method for Determination of Intrinsic Viscosity for Any Polymer with High Precision

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Chinese Journal of Polymer Science 2014年第2期32卷 209-217页

作者：熊晓鹏 Qi-rong Ke Shi-qin Zhu Department of Materials Science and Engineering College of Materials Xiamen University fujian Provincial Key Laboratory of Polymer Materials Fujian Normal University institut für Physikalische chemie der Johannes Gutenberg-universit t Mainz

Intrinsic viscosities for a given polyelectrolyte in salt free and low-salt solvents reported in literatures are normally not comparable, because of inadequate valuation procedures. this article describes a theoretically justified reliable method, which is free of any model assumptions： the so called Wolf plot （logarithm of the relative viscosity as a function of polymer concentration） enables the unequivocal determination of intrinsic viscosities for all kinds of macromolecules, irrespective of whether they are chain molecules of different architecture or globular polymers, whether they are charged or uncharged. the validation of the method was examined by evaluation of the viscosities of a polyelectrolyte, some uncharged polymers of different architectures, uncharged polymer blends, and some literature data.

关键词： Intrinsic viscosity Polyelectrolyte New method Wolf plot Introduction.

tiO2-incorporated polyelectrolyte composite membrane with transformable hydrophilicity/hydrophobicity for nanofiltration separation

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Chinese Journal of Chemical Engineering 2020年第10期28卷 2533-2541页

作者： Yahua Lu Zhenping Qin Naixin Wang Hongxia Guo Quanfu An Yucang Liang Beijing Key Laboratory for Green Catalysis and Separation College of Environmental and Energy EngineeringBeijing University of TechnologyBeijing 100124China College of Materials Science and Engineering Beijing University of TechnologyKey Laboratory of Advanced Functional MaterialsMinistry of EducationBeijing 100124China institut für anorganische chemie Eberhard Karls Universität TübingenAuf der Morgenstelle 18Tübingen 72076Germany

the wettability of the membrane surface has shown obvious influent on the separation performance of the *** this work,a hydrophilic PDA-[PDDA/tiO2]+Cl-membrane was prepared by a one-step codeposition of poly(diallyldimethylammonium chloride)(PDDA)polyelectrolyte solution containing positively charged tiO2@PDDA nanoparticles with the assistance of dopamine(DA).Such positively charged membrane can be transformed into a hydrophobic membrane PDA-[PDDA/tiO2]+PfO-via the counterion exchange between Cl-and PfO-(perfluorooctanoate).the transformation between hydrophilicity and hydrophobicity is *** both hydrophilic and hydrophobic membranes,the nanofiltration performances were respectively investigated by the aqueous solution and ethanol solution of dyes including methyl blue(MB),Congo red(Cr)and Evans blue(EB),and as well metal salt aqueous *** consecutive running stability and anti-fouling performance of both hydrophilic and hydrophobic membranes were *** results revealed that both membranes showed high nanofiltration performances for retention of dyes in(non)aqueous *** the hydrophilic membrane,the rejection of salts in a sequence is MgSO4>Na2SO4>MgCl2>***,both of the hydrophilic and hydrophobic membranes showed high stability and antifouling property.

关键词： Counterion exchange Wettability reversibility Dopamine tiO2-incorporated polyelectrolyte composite membrane (non)aqueous nanofiltration

三正丁基膦稳定的铜(Ⅰ)β-二酮配合物的合成、表征以及作为前驱物用化学汽相沉积法生长铜膜(英文)

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无机化学学报 2004年第11期20卷 1257-1264页

作者：沈应中 Marion Leschke Stefan E. Schulz ramona Ecke thomas Gessner Heinrich Lang technische universitt Chemnitz Fakultat für Naturwissen-schaften Institut für Chemie Lehrstuhl Anorganische Chemie Straae der Nationen 62 09111 Chemnitz Germany technische universitat Chemnitz Fakultat fü Elektrotechnik und Informationstechnik Zentrum fü Mikrotechnologien Reichenhainer Straae 70 09126 Chemnitz Germany

合成了一系列三正丁基膦辅助配体稳定的铜髣β鄄二酮配合物,对合成的配合物用元素分析、红外、核磁共振以及热重和差热等手段进行了表征。筛选出性能优良的配合物为前驱物用化学汽相沉积(CVD)的方法生长出金属铜膜,用SEM和EDX等手段对... 详细信息

合成了一系列三正丁基膦辅助配体稳定的铜髣β鄄二酮配合物,对合成的配合物用元素分析、红外、核磁共振以及热重和差热等手段进行了表征。筛选出性能优良的配合物为前驱物用化学汽相沉积(CVD)的方法生长出金属铜膜,用SEM和EDX等手段对生长的铜膜进行了表征。

关键词：三正丁基膦铜配合物 β-二酮合成前驱物化学汽相沉积法铜膜热分析扫描电镜 ×-射线能量散射

Modeling of Long-range Intra- and Inter-Species Charged Particle Collisions for PIC Simulations

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Communications in Computational Physics 2010年第5期7卷 877-903页

作者： D.D’Andrea C.-D.Munz r.Schneider forschungszentrum karlsruhe-in der Helmholtz-Gemeinschaft Institut fur Kern-und EnergietechnikPF 3640D-76021 KarlsruheGermany institut fur Aerodynamik und Gasdynamik Universitat StuttgartPfaffenwaldring 21D-70550 StuttgartGermany forschungszentrum karlsruhe-in der Helmholtz-Gemeinschaft Institut fur Hochleistungsimpuls und MikrowellentechnikPF 3640D-76021 KarlsruheGermany

In this paper we present the modelling of elastic intra-species electron-electron and inter-species electron-ion scattering in a plasma on the basis of the fokkerPlanck collision *** into account the equivalence of this operator with a stochastic differential equation,we propose a Particle-in-Cell based approach for the numerical solution of the fokker-Planck collision *** we will see,the introduced numerical concept allows the simulation of the collisional relaxation process in a fully self-consistent fashion.

关键词： Coulomb collisions in plasmas collisional relaxation fokker-Planck equation stochastic differential equation particle-in-cell method

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过渡金属多烯烃配合物的合成与反应

有机化学 1986年第1期 62-68页

作者： JrnMüller institut für anorganische und Analytische chemie der technischen universitt/Berlin W.Germany

一、在异丙基澳化镁存在下1,5-环辛二烯低价过渡金属氯化物的反应例如,三氯化铑与双烯烃反应可得到双烯烃氯化铑配合物,乙醇既是溶剂,又是还原剂。此外,等双烯烃也都可以与rhCl反应生成相应的配合物。1.1,5-环辛二烯氯化铑1与环多烯烃反... 详细信息

一、在异丙基澳化镁存在下1,5-环辛二烯低价过渡金属氯化物的反应例如,三氯化铑与双烯烃反应可得到双烯烃氯化铑配合物,乙醇既是溶剂,又是还原剂。此外,等双烯烃也都可以与rhCl反应生成相应的配合物。1.1,5-环辛二烯氯化铑1与环多烯烃反应1可与环多烯烃反应,生成1,5-环辛二烯铑烯丙基型配合物。由于苯的共振能较高,故1不能与它发生反应。

关键词：配合物多烯烃过渡金属过渡元素

tHE CHEMICAL PrOPErtIES Of ALKALI MEtALS HEPtAPHOSPHIDES

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THE CHEMICAL PROPERTIES OF ALKALI METALS HEPTAPHOSPHIDES

第17届国际磷化学大会

作者： V.A.Miluykov O.G.Sinyashin A.V.Kataev P.Lonnecke E.Hey-Hawkins A.E.Arbuzov institute of organic and physical chemistry russan academie of sciences KazanRussia A.E.Arbuzov institute of organic and physical chemistry russan academie of sciences KazanRussia A.E.Arbuzov institute of organic and physical chemistry russan academie of sciences KazanRussia institut für anorganische chemie der universitt Leipzig LeipzigGermany institut für anorganische chemie der universitt Leipzig LeipzigGermany

＜正＞the alkali metals polyphosphides （homopolyatomic phosphorus clusters, Zintl-anions） are currently in focus of research both as intermediates of elemental phosphorus transformation in

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含长链亚烷基桥的芳炔类共轭大环的合成

高等学校化学学报 2007年第1期28卷 65-70页

作者：程晓红 Hoeger Sigurd 云南大学化学科学与工程学院教育部化学自然资源药物化学重点实验室昆明650091 institut für technische chemie und Polymerchemie Universitt KarlsruheEngesserstr

采用模板导向法高产率地合成了两个含长链亚烷基桥的芳炔类共轭大环.通过四碘化合物与单保护双炔化合物的四重Hagiraha偶合反应构建了环化所需要的复杂前体.通过相应的模板四炔衍生物的分子内G laser偶合反应环化得到大环.大环的结构用N... 详细信息

采用模板导向法高产率地合成了两个含长链亚烷基桥的芳炔类共轭大环.通过四碘化合物与单保护双炔化合物的四重Hagiraha偶合反应构建了环化所需要的复杂前体.通过相应的模板四炔衍生物的分子内G laser偶合反应环化得到大环.大环的结构用NMr,GPC及UV-V is表征确证.

关键词：大环芳炔基模板双轴向列相液晶