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Degree of style coiling is associated with corolla-tube length in the nectarless flowers of Roscoea schneideriana

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Plant Diversity 2023年第6期45卷 748-751页

作者： Bo Wang Ze-Yu Tong Ying-Ze Xiong Xiao-Fan Wang W.Scott Armbruster Shuang-Quan Huang State Key Laboratory of Hybrid Rice College of Life SciencesWuhan UniversityWuhan 430072China Institute of Evolution and Ecology School of Life SciencesCentral China Normal UniversityWuhan 430079China School of Biological Sciences University of PortsmouthPortsmouth PO12DYUK Institute of Arctic Biology University of Alaska FairbanksFairbanksAK 99775USA

The plant-pollinator‘arms race’model posits that a major driver of the evolution of elongated corollas in flowers is reciprocal selection for‘morphological fit’between pollinator-tongue length and access distance to nectar(usually corolla-tube length).Evidence for the pollinator-mediated selection on tube length and evolution of multiple,correlated floral traits remains *** gain possible insights into the strength of stabilizing selection by assessing standing phenotypic variation,we measured a series of functionally important floral traits,including corolla tube length and‘effective’tube depth and degree of style *** then calculated coefficients of variation(CV)for these traits in three field populations of *** in most long-tubed flowers,the bottom part of the corolla tube is completely occupied by the style,with no room for *** length of this portion of the corolla tube was more variable(higher CV)than the upper part of the corolla tube,suggesting that functional tube depth was under stronger stabilizing *** degree of style coiling was negatively related to the corolla-tube length in all three populations of ***,suggesting that there may be conflicting selection acting on style length and corolla-tube length,which are otherwise usually tightly *** the lack of nectar in the flowers of this species,the long corolla tubes and long styles may represent morphological holdovers from ancestors that were pollinated by long-tongued pollinators,as is still seen in related species in the western Himalayas.

关键词： Coefficient of variation Coiled style Corolla-tube length Nectar depth Pollinator shift Trait covariation

Local and Global Character Sums

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Acta Mathematica Sinica,English Series 2000年第3期16卷 535-540页

作者： Chunlei Liu Zhengzhou University of Information Engineering,Zhengzhou 450002,P.R.China Zhengzhou University of Information Engineering Zhengzhou 450002 P. R. China

Hua’s estimate is established for character sums in a number field.A relationship between liftings of a character sum in a local field is also studied.

关键词： Character sum Exponential sum

SYNTHESIS OF NOVEL LIQUID CRYSTALLINE POLY(METH)ACRYLATES CONTAINING SILOXANE SPACER AND TERPHENYLENE MESOGENIC UNIT

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Chinese Journal of Polymer Science 2000年第2期18卷 101-107页

作者： Zhi-qian Zang Yu-fei Luo Dong Zhang Xin-hua Wan Qi-feng Zhou Department of Polymer Science & Engineering, College of Chemistry, Peking University, Beijing 100871, China 北京大学北京

Novel side-chain liquid-crystalline poly(meth)acrylates were synthesized using 1-(3-hydroxyl-propyl)-3-[(4 '-cyano-p-terphenyloxycarbonyl)alkyl]-1,1,3,3-tetramethyldisiloxane as the key intermediate. The polymers used a disiloxane moiety as decoupling spacer with cyano-p-terphenyl as mesogenic unit. The products were characterized by NMR, GPC, DSC and polarizing optical microscopy. All the polymers with cyano-p-terphenyl mesogens formed a stable mesophase. However, if the mesogenic unit is replaced by cyano-p-biphenyl, the liquid crystalline character will be lost. The results also showed that the decoupling is incomplete even if a complex and very flexible decoupling spacer is deliberately incorporated to obtain the highest possible decoupling effect.

关键词： liquid crystalline polymers polyacrylates 4 ''-cyano-p-terphenyl

Enamine Configuration of 5-Methyl-2-phenyl-4- [(Z)-3-tolylamino-phenylmethylene]pyrazol-3(2H)-one

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Chinese Journal of Structural Chemistry 2005年第8期24卷 957-961页

作者： QIAO Yu-Qin Lü Xing-Qiang BAO Feng KANG Bei-Sheng School of Chemistry and Chemical Engineering Sun Yat-Sen University ChinaGuangzhou 510275

Compound 5-methyl-2-phenyl-4-[（Z）-3-tolylamino-phenylmethylene]pyrazol-3（2H）-one （C24H21N3O） crystallizes in the triclinic system, space group P1, with a = 9.267（3）, b = 9.904（4）,c = 12.035（4） A°, α = 97.896（6）, β = 103.865（6）, γ = 107.950（6）°, Mr= 367.44, Z = 2, V = 993.2（6）A°^3,Dc = 1.229 g/cm^3,μ（MoKa） = 0.077 mm^-1 and F（000） = 388. The structure was refined to R =0.0444 and wR = 0.1199 for 2903 observed reflections （I 〉 2σ（I））. The results of ^1H NMR and single-crystal X-ray diffraction studies showed the enamine character of the compound. The strong intramolecular hydrogen bonds in the large conjugate system, together with weak intermolecular C-H……π hydrogen bonding and π……π stacking, lead to the formation of a multi-dimensional supramolecular network.

关键词： 5-methyl-2-phenyl-4-[(Z)-3-tolylamino-phenylmethylene]pyrazol-3(2H)-one,enamine weak interaction snpramolecnlar network

Synthesis and Crystal Structure of N-(5-Phenylseleno)pentyl Succinimide

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Chinese Journal of Structural Chemistry 2002年第5期21卷 517-519页

作者：张万轩于海涛等 DepartmentofChemistry NankaiUniversityTianjin300071China

N-(5-phenylseleno)pentyl succinimide 1, C15H19NO2Se (Mr = 324.27), was prepared by treating Br(CH2)5SePh with potassium succinimide. Its crystal structure has been determined by X-ray single-crystal diffraction. The crystal of 1 belongs to monoclinic system, space group P21/c with the crystal cell parameters: a = 18.018(6), b = 5.980(2), c = 14.682(5) ? = 109.977(6)? V = 1486.7(9) 3, Z = 4, Dc = 1.449 g/cm3, (MoK? = 2.523 mm-1, F(000) = 664,the final R = 0.0302 and wR = 0.0666 for 2623 independent observed reflections with I > 2(I). Structure analyses revealed that there exist strong nonclassical hydrogen bonds (CH…O).

关键词： N-(5-苯基硒基)戊烷基琥珀酰亚胺合成晶体结构 C15H19NO2Se

Synthesis and Crystal Structure of an Ion-pair Supramolecular Associate 2,9-Diformyl-1,10-phenanthrolinebis-(2,6-dimethylanil)cobalt(Ⅱ) Perchlorate

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Chinese Journal of Structural Chemistry 2006年第7期25卷 861-865页

作者： LI Gang JIE Su-Yun TANG Ning SUN Wen-Hua State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000 China Key Laboratory of Engineering Plastics Institute of Chemistry The Chinese Academy of Sciences Beijing 100080 China

2,9-Diformyl-l, 10-phenanthrolinebis（2,6-dimethylanil）cobalt（Ⅱ） perchlorate was synthesized and demonstrated to be [COL2][ClO4]2 by X-ray diffraction analysis. It crystallizes in the monoclinic system, space group C2/c with a = 22.294（4）, b = 15.122（3）, c = 20.640（4） A, β = 119.618（4）°, V = 6048.9（19） A^3, C63H52Cl2CoN9O9, Mr= 1208.97, F（000） = 2504, De= 1.328g/cm^3, Z = 4, μ= 0.436, the final R = 0.0712 and wR = 0.1718 for 1734 observed reflections （I 〉 2σ（I））. In its solid state the helical polymeric chains are supramolecularly associated through intermolecular and interionic hydrogen bonding interactions.

关键词： 1,10-phenanthroline cobalt complex crystal structure hydrogen bond

Synthesis and Crystal Structure of 7-Nitro-5-sulfo-napthalene-1,4-dicarboxylate Acid

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Chinese Journal of Structural Chemistry 2006年第7期25卷 849-853页

作者： WU Rui-Feng ZHANG Tong-Lai QIAO Xiao-Jing ZHANG Jian-Guo YANG Li YU Wei State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology Beijing 100081 China College of Chemical Engineering Inner Mongolia University of Technology Hohhot 010051 China

The title compound （C12H15NO13S, Mr = 413.31） was synthesized by the nitration of napthalene-1,4-dicarboxylate acid in mixed nitric and sulfuric acids. It crystallizes in monoclinic, space group P2 1/c with a = 8.100（1）, b = 24.369（3）, c = 8.634（1） A, β = 105.380（2）°, V = 1643.1（4） A^3, Z = 4, Dc = 1.671 g/cm^3, F（000） = 856, μ（MoKa） = 0.273 mm^- 1, T = 294（2） K, the final R = 0.0400 and wR = 0.1021 for 2866 observed reflections with I 〉 2σ（I）. In this crystal there exist a number of H-bonds which link the molecules to form a three-dimensional infinite network structure. The thermal decomposition of the title compound was investigated by using TG-DTG and DSC techniques.

关键词： 7-nitro-5-sulfo-napthalene-1,4-dicarboxylate acid crystal structure thermal analysis

TESTING OF CORRELATION AND HETEROSCEDASTICITY IN NONLINEAR REGRESSION MODELS WITH DBL(p,q,1) RANDOM ERRORS

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Acta Mathematica Scientia 2008年第3期28卷 613-632页

作者：刘应安韦博成 College of Information Science and Technology Nanjing Forestry University Department of Mathematics SoutheastUniversity

Chaos theory has taught us that a system which has both nonlinearity and random input will most likely produce irregular data. If random errors are irregular data, then random error process will raise nonlinearity （Kantz and Schreiber （1997））. Tsai （1986） introduced a composite test for autocorrelation and heteroscedasticity in linear models with AR（1） errors. Liu （2003） introduced a composite test for correlation and heteroscedasticity in nonlinear models with DBL（p, 0, 1） errors. Therefore, the important problems in regression model axe detections of bilinearity, correlation and heteroscedasticity. In this article, the authors discuss more general case of nonlinear models with DBL（p, q, 1） random errors by score test. Several statistics for the test of bilinearity, correlation, and heteroscedasticity are obtained, and expressed in simple matrix formulas. The results of regression models with linear errors are extended to those with bilinear errors. The simulation study is carried out to investigate the powers of the test statistics. All results of this article extend and develop results of Tsai （1986）, Wei, et al （1995）, and Liu, et al （2003）.

关键词： DBL(p q 1) random errors nonlinear regression models score test heteroscedasticity correlation

CO-ISOMETRIC SOLUTIONS OF EQUATION CU + U*C = 2D

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Acta Mathematica Scientia 2003年第2期23卷 192-200页

作者：杜拴平侯晋川 Department of Mathematics Shanxi University Department of Mathematics Shanxi Teachers University

This note discusses the co-isometric solutions of the operator equation CU + U*C = 2D, establishes a correspondence between such solutions and the self-adjoint solutions of the algebraic Riccati equation X2 - iDX + iXD + D2 - C2 = 0, and gives all possible co-isometric solutions parametrically. Some mistakes of Dobovivsek's results are corrected.

关键词： Co-isometric operator invariant subspace factorization