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Chemical Research in Chinese Universities 2009年第4期25卷 579-584页

作者： CHEN Dan-mei DONG Yan-ming SHEN Bing-xing YANG Xue-hui LI Yan-jie HU Xiao-lan Department of Materials Science and Engineering Xiamen University Xiamen 361005 P. R. China College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P. R. China

A series of bowlic cyclotriveratrylenes（CTV） with peripheral groups with different lengths were *** compounds were investigated by diferential scanning calorimetry and hot stage coupled polarizing *** CTV derivatives show thermotropic liquid crystalline *** experimental results of their thermotropic liquid crystalline behavior indicate that the clear points,the entropy changes of melting points,the crystallization temperatures,and their entropy changes all exhibited an evident odd-even effect except the melting points,which decreased monotonously with the increase of the length of the alkoxy *** parameter values of CTVs with even number carbon atoms were larger than those of CTVs with odd *** the length of alkoxyl chains was even longer,a monotonous decrease ***,in the case of the entropy changes of both melting points and crystallization temperatures,the effect was valid for all the six species,and therefore,the whole curves presented as a zig-zag form.

关键词： Cyclotriveratryleues(CTV) Bowlic liquid crystal Thermotropic liquid crystal odd-even effect

odd-even effect OF LYOTROPIC LIQUID CRYSTALLINE PROPERTIES OF AROMATIC-ALIPHATIC COPOLYAMIDES

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Chinese Journal of Polymer Science 2001年第1期19卷 103-106页

作者： Xiao-zhong Lu Yan-qing Lian Xiao-gong Wang Qi-xiang Zhou De-shan Liu Department of Chemical Engineering and School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

A series of aromatic-aliphatic copolyamides containing different aliphatic diamine units was synthesized by low temperature solution *** liquid crystalline critical concentration(c^(*))and liquid crystalline critical temperature(T^(*))of these copolyamides exhibited an odd-even zigzag effect with the odd-even variation of carbon atom number in the aliphatic diamines used.

关键词： odd-even effect copolyamide lyotropic phase transition

Special odd-even effect of Degree of Oligomerization on Properties of Cyclic Oligoesters

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Chinese Journal of Polymer Science 2015年第8期33卷 1069-1069,1070-1073页

作者： Jun Wu Tao-guang Qu Ling-feng Gao Xiao-ming Yang Xiao-hong Li 屠迎锋 Xiu-lin Zhu Suzhou Key Laboratory of Macromolecular Design and Precision Synthesis Jiangsu Key Laboratory of Advanced Functional Polymer Design and ApplicationCollege of ChemistryChemical Engineering and Materials ScienceSoochow University

We demonstrate here seven pure cyclic samples, which belongs to two series of oligoesters, cyclic oligo（trimethylene terephthalate）s （COTTs） and cyclic oligo（butylene terephthalate）s （COBTs）, showing odd-even effect of degree of oligomerization （repeating units number） on properties. The pentamer of COTT and trimer of COBT show much lower melting temperature, and the trimer of COTT and trimer of COBT show significant lower refractive index, which can be ascribed to the low packing density of cyclic oligoesters with odd number of degree of oligomerization. Our results reveal the discrete property change as a function of cyclic size of oligomers, which can be used to design materials with special properties.

关键词： Cyclic polymer Oligomer odd-even effect Refractive index.

odd-even Sequence effect of Surface-Mediated Peptide Assemblies Observed by Scanning Tunneling Microscopy

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Chinese Journal of Chemistry 2012年第9期30卷 1987-1991页

作者：郭元元王晨轩侯静菲杨爱华张雪梅王宜冰张敏杨延莲王琛 National Center for Nanoseience and Technology Beoing 100190China

The peptide assembly structures of polyglutamine （PolyQ） have been studied by using scanning tunneling microscopy （STM） with high spatial resolution in ambient conditions. 4,4＇-Bipyridyl （4Bpy） was introduced into the PolyQ7 and PolyQ8 peptide assemblies for labeling the C-termini of the peptides. The fine structures of the 4Bpy-PolyQ7 and 4Bpy-PolyQ8 co-assemblies are observed, and the statistics of the apparent peptide strand length reveal different length distributions for PolyQ7 and PolyQs. One predominant apparent peptide strand length is ob- served for PolyQ7 reflecting one predominant peptide conformation in assembly structures, while three major ap- parent strand lengths can be identified with PolyQ8 reflecting three co-existing peptide conformations in peptide as- semblies. Such drastic difference in assembling characteristics can be considered as a reflection of asymmetric ad- sorption effect ofpeptides relating to odd-even residue numbers of PolyQ7 and PolyQ8,

关键词： peptide adsorption conformation odd-even effect scanning tunneling microscopy

Sporophytic nondisjunction of the maize B chromosome at high copy numbers

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Journal of Genetics and Genomics 2010年第1期37卷 79-84页

作者： Rick E.Masonbrink James A.Birchler Division of Biological Sciences University of Missouri

It has been known for decades that the maize B chromosome undergoes nondisjunction at the second pollen *** in-situ hybridization （FISH） was used to undertake a quantitative study of maize plants with differing numbers of B chromosomes to observe if instability increases by increasing B dosage in root tip tissue.B chromosome nondisjunction was basically absent at low copy number,but increased at higher B ***,B nondisjunction rates are dependent on the dosage of B＇s in the *** in nondisjunction were also documented between odd and even doses of the *** plants that have inherited odd numbered doses of the B chromosome,B loss is nearly twice as likely as B gain in a somatic *** comparing plants with even doses of B＇s to plants with odd doses of B＇s,plants with even numbers had a significantly higher chance to increase in ***,the B＇s nondisjunctive capacity,previously thought to be primarily restricted to the gametophyte,is present in sporophytic cells.

关键词： maize Zea mays B chromosome nondisjunction odd-even effect

First-Principles Study on Switching Performance and Spin Filtering Efficiency of Dimethyldihydropyrene/Cyclophanediene Single-Molecule Devices with Zigzag Graphene Nanoribbon Electrodes

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Chinese Journal of Chemical Physics 2024年第5期37卷 644-652,I0066-I0072,I0100页

作者： Chang-Feng Zheng Yan-Qi Mu Zong-Liang Li Guang-Ping Zhang Shandong Key Laboratory of Medical Physics and Image Processing&Shandong Provincial Engineering and Technical Center of Light Manipulations School of Physics and ElectronicsShandong Normal UniversityJinan 250358China

Moleculardeviceswith highswitchingperformance and/or the perfect spin filtering effect have always been the pursuit with the development of molecular ***,yusingthe 2001.0V ***'s function method in combination with the density functionaltheory,the switching performance and spin filtering properties of dimethyldihydropyrene(DHP)/cyclophanediene(CPD)photoswitchable molecule connected by carbon atomic chains(CACs)to two zigzag graphene nanoribbon electrodes have been theoretically *** results show that DHP is more conductive than CPD and therefore an evident switching effect is demonstrated,and the switching ratio(RON/OFF)can reach 4.5×*** is further revealed that the RoON/OF of DHP/CPD closely depends on the length of *** specifically,the RoN/OFF values of DHP/CPD with odd-numbered CACs are larger than those with even-numbered *** interestingly,a high or even perfect spin filtering effect can be obtained in these investigated DHP/CPD single-molecule *** study is helpful for future design of single-molecule switches and spin filters and provides a way to optimize their performance by means of varying the length of bridging CACs.

关键词： Single-molecule switch Spin filtering effect odd-even effect Nonequilibrium Green's function method Density functional theory

Studies on Liquid Crystalline Bis[4-(p-phenoxy)-phenylbenzoate]Alkyldicarboxylat

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Chemical Research in Chinese Universities 1998年第2期14卷 91-95页

作者： XING Pei-xiang TIAN Yan-qing WANG Jun-zuo NA Hui TANG Xin-yi JIANG Bing-zheng Polymer Physics Laboratory Changchun Institute of Applied ChemistryChangchun130022 Department of Chemistry Jilin Univer sityChangchun130023

A new series of liquid crystals of bis[4-(p-phenoxy)-phenylbenzoate]-alkyldicarboxylate which contain two rigid groups connected by a flexible spacer was synthesized. These liquid crystals show nematic phase and were ... 详细信息

关键词： Liquid crystal Nematic phase odd-even effect