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The Correlation Coefficient of Hesitancy Fuzzy Graphs in Decision Making
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作者 N.Rajagopal Reddy S.Sharief Basha 《Computer Systems Science & Engineering》 SCIE EI 2023年第7期579-596,共18页
The hesitancy fuzzy graphs(HFGs),an extension of fuzzy graphs,are useful tools for dealing with ambiguity and uncertainty in issues involving decision-making(DM).This research implements a correlation coefficient meas... The hesitancy fuzzy graphs(HFGs),an extension of fuzzy graphs,are useful tools for dealing with ambiguity and uncertainty in issues involving decision-making(DM).This research implements a correlation coefficient measure(CCM)to assess the strength of the association between HFGs in this article since CCMs have a high capacity to process and interpret data.The CCM that is proposed between the HFGs has better qualities than the existing ones.It lowers restrictions on the hesitant fuzzy elements’length and may be used to establish whether the HFGs are connected negatively or favorably.Additionally,a CCMbased attribute DM approach is built into a hesitant fuzzy environment.This article suggests the use of weighted correlation coefficient measures(WCCMs)using the CCM concept to quantify the correlation between two HFGs.The decisionmaking problems of hesitancy fuzzy preference relations(HFPRs)are considered.This research proposes a new technique for assessing the relative weights of experts based on the uncertainty of HFPRs and the correlation coefficient degree of each HFPR.This paper determines the ranking order of all alternatives and the best one by using the CCMs between each option and the ideal choice.In the meantime,the appropriate example is given to demonstrate the viability of the new strategies. 展开更多
关键词 Hesitancy fuzzy graph correlation coefficient measures ENERGY hesitancy fuzzy preference relationships decision making
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An Iterative Calculating Method for Inbreeding and Relationship Coefficient
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作者 HANDan-dan SONGRen-xue 《Journal of Northeast Agricultural University(English Edition)》 CAS 2001年第1期19-22,共4页
The iterative formulas of inbreeding and relationship coefficients were put forward by using numerator elationship. It is suitable for any none - generation - overlap pedigree. The inbreeding and relationship coeffi- ... The iterative formulas of inbreeding and relationship coefficients were put forward by using numerator elationship. It is suitable for any none - generation - overlap pedigree. The inbreeding and relationship coeffi- ient of offsprings can be calculated by those of parents. The deducing process of numerator relationship is simple and clear comparing with path analysis. An example shows the usage of these formulas. 展开更多
关键词 Inbreeding coefficient relationship coefficient numerator relationship iterative calculating
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Estimation of Average Relationship Coefficient in Animal Population
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作者 YANGYun-qing LUJin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2000年第1期21-24,共4页
It is not reasonable to estimate the average relationship degree in statistics by using the mean of relationship coefficients between the individuals in a animal population.According to different usage of relationship... It is not reasonable to estimate the average relationship degree in statistics by using the mean of relationship coefficients between the individuals in a animal population.According to different usage of relationship coefficient,the estimation method of average relationship coefficient in animal population was disscussed by using Z transformation or CSC transformation,respectively,when relationship coefficient shows relationship degree or probability. 展开更多
关键词 average relationship coefficient estimation method Z transformation CSC transformation
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Numerical Analysis of the Analytical Relationships between Angstrom Coefficients of Aerosols and Their Optical Properties for Four Types of Aerosols
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作者 Idrith Tijjani Bello Sha’aibu Uba Salman Koki Fatima 《Open Journal of Applied Sciences》 2013年第8期490-513,共24页
In this paper, the authors numerically analyzed the analytical relationships between angstrom coefficients and optical properties of aerosols to the existing data extracted from OPAC at the spectral length of 0.25 μm... In this paper, the authors numerically analyzed the analytical relationships between angstrom coefficients and optical properties of aerosols to the existing data extracted from OPAC at the spectral length of 0.25 μm to 2.5 μm at eight relative humidity for desert, urban, marine clean and continental clean aerosols. That is apart from their relationships with the wavelength that was determined, in this paper their relation with respect to aerosols’ type and RHs are determined. The properties extracted are scattering, absorption, and extinction coefficients and single scattering albedo. The results showed that the extinction and single scattering albedo are correct for all the aerosols but single scattering co-albedo is satisfied for only sahara and continental clean. 展开更多
关键词 ANGSTROM coefficientS ANALYTICAL relationshipS Parameterize Wavelength Dependence Optical Properties
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Relationships between femoral strength evaluated by nonlinear finite element analysis and BMD,material distribution and geometric morphology
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作者 He Gong1,Linwei Lv1,Rui Zhang1,Dong Zhu3,Ming Zhang2(1.Department of Engineering Mechanics,Jilin University,Changchun 130025,P.R.China 2.Department of Health Technology and Informatics,The Hong Kong Polytechnic University,Hong Kong,China 3.Department of Orthopedic Surgery,No.1 Hospital,Jilin University,Changchun 130021,China) 《医用生物力学》 EI CAS CSCD 2009年第S1期66-66,共1页
Precisely quantifying the strength of the proximal femur and accurately assessing hip fracture risk would enable those at high risk to be identified so that preventive interventions could be taken.Development of bette... Precisely quantifying the strength of the proximal femur and accurately assessing hip fracture risk would enable those at high risk to be identified so that preventive interventions could be taken.Development of better measures of femoral strength using the clinically 展开更多
关键词 BMD relationships between femoral strength evaluated by nonlinear finite element analysis and BMD material distribution and geometric morphology FEA
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Structural Characterization and Octanol/water Partition Coefficients(LogP) Prediction for Oxygen-containing Organic Compounds 被引量:8
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作者 廖立敏 黄茜 雷光东 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第8期1243-1250,共8页
New descriptors were constructed and structures of some oxygen-containing organic compounds were parameterized. The multiple linear regression(MLR) and partial least squares regression(PLS) methods were employed t... New descriptors were constructed and structures of some oxygen-containing organic compounds were parameterized. The multiple linear regression(MLR) and partial least squares regression(PLS) methods were employed to build two relationship models between the structures and octanol/water partition coefficients(LogP) of the compounds. The modeling correlation coefficients(R) were 0.976 and 0.922, and the "leave one out" cross validation correlation coefficients(R(CV)) were 0.973 and 0.909, respectively. The results showed that the structural descriptors could well characterize the molecular structures of the compounds; the stability and predictive power of the models were good. 展开更多
关键词 oxygen-containing organic compounds octanol/water partition coefficients(LogP) structural descriptors relationship between structures and properties
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Experimental and QSPR Studies on n-Octanol/water Partition Coefficient (lgK_(ow)) of Substituted Aniline 被引量:4
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作者 戴勇 江建林 +1 位作者 王遵尧 薛群 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第12期1449-1454,共6页
The n-octanol/water partition coefficients (lgKow) of 18 substituted anilines were determined at 25 ℃ by shake-flask method. The geometrical optimization of substituted anilines has been performed at B3LYP/6-311G^... The n-octanol/water partition coefficients (lgKow) of 18 substituted anilines were determined at 25 ℃ by shake-flask method. The geometrical optimization of substituted anilines has been performed at B3LYP/6-311G^** level with Gaussian98 program, and the molecular surface areas of substituted anilines were calculated using ChemOffice 2004 program. The calculated structural parameters of substituted anilines were used as theoretical descriptors and the two-parameter (molecular surface area (MA) and the energy of the highest occupied molecular orbital (EaoMo)) quantitative structure-property relationship (QSPR) model of lgKow for substituted aniline with molecular structural parameters was developed by multi-linear regression method. The regression coefficient square (r^2) is 0.990 and the standard deviation SE 0.109. The model was validated by variance inflation factors (VIF) and t-test, and the results show that there exists small self-correlation between variables of the model with perfect stability. The model gives results in good qualitative agreement with experimental data. At last, the model was applied to predict lgKow values of five substituted anilines whose lgKow values have not been determined experimentally. 展开更多
关键词 substituted aniline n-octanol/water partition coefficient shake-flask method DFT quantitative structure-property relationship (QSPR)
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DFT and Position of Cl Substitution (PCS) Methods Studies on n-Octanol/water Partition Coefficients (lgK_(ow)) and Aqueous Solubility (–lgS_w) of All PCDD Congeners 被引量:5
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作者 谢亚杰 赵惠明 +1 位作者 王遵尧 张雅荣 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第12期1409-1418,共10页
Optimized calculations of 75 PCDDs and their parent DD were carded out at the B3LYP/6-31G* level by density functional theory (DFT) method. The structural parameters were obtained and significant correlation betwee... Optimized calculations of 75 PCDDs and their parent DD were carded out at the B3LYP/6-31G* level by density functional theory (DFT) method. The structural parameters were obtained and significant correlation between the C1 substitution position and some structural parameters was found. Consequently, the number of C1 substitution positions was taken as theoretical descriptors to establish two novel QSPR models for predicting lgKow and -lgSw of all PCDD congeners. The two models achieved in this work contain two variables (Na and Nβ), of which r = 0.9312, 0.9965 and SD = 0.27, 0.12 respectively, and t values are all large. The variation inflation factors (VIF) of variables in the two models herein are both less than 5.0, suggesting high accuracy of the lgKow and -lgSw predicting models, and the results of cross-validation test also show that the two models exhibit optimum stability and good predictive power. By comparison, the correlation and predictive ability of the present work are more advantageous than those obtained using semi-empirical AM1 and GC-RI methods. 展开更多
关键词 polychlorinated dibenzo-p-dioxins (PCDDs) n-octanol/water partition coefficients(lgKow) aqueous solubility (-lgSw) quantitative structure-property relationship (QSPR) DFT position of CI substitution (PCS) method
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QSPR of n-Octanol/water Partition Coefficient (lgK_(ow)) for Alkyl(1-phenylsulfonyl) Cycloalkane-carboxylates 被引量:4
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作者 翟志才 柳红霞 +1 位作者 王遵尧 赵林飞 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第2期143-150,共8页
Quantum chemistry parameters of 28 alkyl(1-phenylsulfonyl) cycloalkane-carboxy-lates were computed at the 6-31G* level in fully optimal manner using B3LYP method of density functional theory (DFT). With GQSARF2.0... Quantum chemistry parameters of 28 alkyl(1-phenylsulfonyl) cycloalkane-carboxy-lates were computed at the 6-31G* level in fully optimal manner using B3LYP method of density functional theory (DFT). With GQSARF2.0 program, the correlation equations that can predict n-octanol/water partition coefficient (lgKow) were developed using the structural and thermodynamic parameters of 28 alkyl(1-phenylsulfonyl) cycloalkane-carboxylates with experimental data of lgKow as theoretical descriptors; the correlation coefficient (R^2) was 0.9452 and the cross-validation squared correlation coefficient (Rcv^2) 0.9312. Furthermore, a four-variable model from MEDV was obtained, of which R2 = 0.9497 and Rov^2 =0.9388. The models were validated by variance inflation factor (VIF) and t-test. Cross-validation indicates that the correlation and predicting ability of the model based on both DFT method and MEDV are more advantageous than those obtained from semi-empirical AM1 method. 展开更多
关键词 quantitative structure-property relationship (QSPR) alkyl(1-phenylsulfonyl) cycloalkane-carboxylate density functional theory (DFT) n-octanol/water partition coefficient (lgKow) molecular electronegativity distance vector (MEDV)
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Studies of n-Octanol/water Partition Coefficients (lgK_(ow)) for Organophosphate Compounds by Density Functional Theory 被引量:2
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作者 LIU Hong-Xia WANG Zun-Yao +2 位作者 ZHAI Zhi-Cai LIU Hong-Yan WANG Lian-Sheng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第3期367-373,共7页
Optimized calculation of 35 dialkyl phenyl phosphate compounds (OPs) was carded out at the B3LYP/6-31G^* level in Gaussian 98 program. Based on the theoretical linear solvation energy relationship (TLSER) model, ... Optimized calculation of 35 dialkyl phenyl phosphate compounds (OPs) was carded out at the B3LYP/6-31G^* level in Gaussian 98 program. Based on the theoretical linear solvation energy relationship (TLSER) model, the obtained parameters were taken as theoretical descriptors to establish the novel QSPR model for predicting n-octanol/water partition coefficients (lgKow) of OPs. The new model achieved in this work contains three variables, i.e., molecular volume (Vm), dipole moment of the molecules (μ) and enthalpy (H^0). For this model, R^2 = 0.9167 and SD = 0.31 at large t values. In addition, the variation inflation factors (VIF) of variables are all close to 1.0, suggesting high accuracy of the predicting model. And the results of cross-validation test (q^2 = 0.8993) and method validation also showed the model of this study exhibited optimum stability and better predictive power than that from semi-empirical method. The model achieved can be used to predict IgKow of congeneric compounds. 展开更多
关键词 organophosphate compounds (OPs) n-octanol/water partition coefficients (Kow) quantitative structure-property relationship (QSPR) density functional theory (DFT)
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Studies on morphology and biomechanics of the coronary arteries
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作者 姜宗来 《Journal of Medical Colleges of PLA(China)》 CAS 1995年第3期237-242,共6页
Morphology and biomechanics of the coronary arteries have been studied in the human and common experimental animals since 1979. The types of the coronary distribution, the artery-vein relationship,and the intramural v... Morphology and biomechanics of the coronary arteries have been studied in the human and common experimental animals since 1979. The types of the coronary distribution, the artery-vein relationship,and the intramural vascular changes and the coronary colla 展开更多
关键词 CORONARY artery morphology COLLATERAL circulation vascular smooth muscle collagen ELASTIN BIOMECHANICS STRESS-STRAIN relationship
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Evolution of zinc morphology during continuous electrodeposition
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作者 Ailing Fan +1 位作者 M.Kurosaki 《Journal of University of Science and Technology Beijing》 CSCD 2003年第1期35-38,共4页
The morphology evolution of zinc continuous electrodeposits with nano-sized crystals on the ferrite substrate has been studied by in-situ scanning tunnel spectroscopy (STM). It is found that the morphology of zinc ele... The morphology evolution of zinc continuous electrodeposits with nano-sized crystals on the ferrite substrate has been studied by in-situ scanning tunnel spectroscopy (STM). It is found that the morphology of zinc electrodeposits varies from initial granules with a size of about 30nm to layered platelets with increasing deposition time. Meanwhile, the crystal structure of the zinc electrodeposits is identified to be hexagonal η-phase by X-ray diffraction. The orientation relationship between zinc crystals and the substrate surface can be interpreted in terms of the misfit and the atomic correspondence of the interphase boundary between the η-phase deposits and α-Fe substrate. 展开更多
关键词 Zn electrodeposit crystal morphology epitaxial growth orientation relationship scanning tunnel spectroscopy
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QSPR Studies on the Octanol/water Partition Coefficient (lgK_(ow)) of Substituted Anilines with 2D and 3D Methods
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作者 李小林 刘红玲 +1 位作者 王遵尧 于红霞 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第3期387-395,共9页
Octanol/water partition coefficient (Kow) is a crucial property for evaluating the environmental behavior and fate of organic compound. Herein, some quantitative structure-property relationship (QSPR) studies were... Octanol/water partition coefficient (Kow) is a crucial property for evaluating the environmental behavior and fate of organic compound. Herein, some quantitative structure-property relationship (QSPR) studies were performed to estimate and predict the lgK ow of substituted anilines. 2D method (multiple linear regression, MLR) and 3D method (comparative molecular field analysis, CoMFA) were applied in this study. Successful 2D and 3D models yielded the correlation coefficient (R2) values of 0.981 and 0.966 and the Leave-One-Out (LOO) cross-validated correlation coefficient (q2) values of 0.933 and 0.820, respectively. The developed models have a highly predictive ability in both internal and external validation. In addition, the results were interpreted in terms of physical and chemical meanings of descriptors and field contribution maps. It showed that the steric and electrostatic properties are the primary factors that govern the lgK ow of substituted anilines. The information obtained from the QSPR models would be helpful to the interpretation of structural features pertinent to the lgK ow of substituted anilines, which may be helpful in estimating the organic compounds' potential harm to the environment. 展开更多
关键词 octanol/water partition coefficient substituted anilines quantitative structure- property relationship multiple linear regression comparative molecular field analysis
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Morphology characteristics of joint surface in rock mass
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作者 胡建华 阮德修 +1 位作者 罗先伟 周科平 《Journal of Central South University》 SCIE EI CAS 2012年第10期2918-2925,共8页
In order to quantify the characteristics of the surface of jointed rock mass,new equipment,the three-dimensional laser surface topography instrument,was used to accurately measure surface morphology of joints.Scan pic... In order to quantify the characteristics of the surface of jointed rock mass,new equipment,the three-dimensional laser surface topography instrument,was used to accurately measure surface morphology of joints.Scan pictures and parameters were obtained to describe the rock joint surface characteristics,for example,the height frequency of surface,and mean square roughness.Using the method of fractal dimension,the values of joint roughness coefficient(JRC) were calculated based on the above parameters.It could access to the joint surface rock sample morphology of the main parameters of characteristic.The maximum peak height is 2.692 mm in the test joint plane.The maximum profile height is 4.408 mm.JRC value is 6.38 by fractal dimension computing.It belongs to the smooth joint surface.The results show that it is a kind of the effective method to quantitatively evaluate the surface topography by the three-dimensional laser surface topography instrument and the fractal dimension method.According to the results,during the process of underground large-scale mining,safe measures to prevent slip failure of the joint plane by controlling surface tension and shear mechanical response were proposed. 展开更多
关键词 joint surface morphology characteristic fi'actal dimension joint roughness coefficient
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基于GBS测序的湘东黑山羊的亲缘关系及近交系数 被引量:2
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作者 刘海林 江为民 +4 位作者 段洪峰 李昊帮 罗璋 李安定 龚龑 《湖南农业大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第2期78-85,共8页
利用基因分型测序(GBS)对60只湘东黑山羊(9只公羊、51只母羊)进行基因组测序,获得湘东黑山羊染色体上的SNP数据和连续纯合子片段(ROH)数据。通过SNP数据进行基于G矩阵的基因组亲缘关系分析和NJ聚类分析,构建湘东黑山羊的群体家系结构,... 利用基因分型测序(GBS)对60只湘东黑山羊(9只公羊、51只母羊)进行基因组测序,获得湘东黑山羊染色体上的SNP数据和连续纯合子片段(ROH)数据。通过SNP数据进行基于G矩阵的基因组亲缘关系分析和NJ聚类分析,构建湘东黑山羊的群体家系结构,并通过ROH数据得到群体平均近交系数。结果表明,60只湘东黑山羊的平均测序深度为9.15X,与参考基因组比对率平均为99.59%;在SNP检测过程中,3只母羊不符合基因型数据质控标准,将其过滤后获得其他57只黑山羊29条染色体上153046个SNPs位点和1937个ROH片段;构建的湘东黑山羊8个家系,其中9只公羊和6只母羊被分为7个家系,另42只母羊被单独分类;基于ROH片段分析的湘东黑山羊群体中每个个体的近交系数均值为0.047,说明湘东黑山羊公羊在繁育过程中有较大的利用空间。 展开更多
关键词 湘东黑山羊 基因分型测序 单核苷酸多态性 连续纯合子片段 近交系数 亲缘关系
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基于3D激光扫描技术的粗集料三维形态特征分析 被引量:1
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作者 汤文 谢明杰 黄丹 《北京工业大学学报》 CAS CSCD 北大核心 2024年第8期948-957,共10页
为了能够建立精确的沥青混合料细观力学模型、优化混合料性能,需要先构建具有真实形态学特征的集料模型并计算分析集料形态参数,利用3D激光扫描技术采集了辉绿岩、石灰岩、玄武岩与卵石4种集料共500颗样本的三维点云数据,通过球谐函数... 为了能够建立精确的沥青混合料细观力学模型、优化混合料性能,需要先构建具有真实形态学特征的集料模型并计算分析集料形态参数,利用3D激光扫描技术采集了辉绿岩、石灰岩、玄武岩与卵石4种集料共500颗样本的三维点云数据,通过球谐函数简化集料模型,建立了三维集料样本库。归纳总结了现有集料的形态指标,通过皮尔逊相关性分析,选取F_(I)、A_(I)定量表征粗集料三维形态特征,对不同种类以及粒径集料的F_(I)、A_(I)进行统计分析。研究结果显示:当球谐序列阶数为10,三角形映射网格数为643时,简化后集料模型基本形状、体积与表面积均与真实集料非常接近;集料的F_(I)、A_(I)服从正态分布与对数正态分布,且随集料类型和粒径的变化而变化。 展开更多
关键词 沥青混合料 粗集料 三维激光扫描 球谐函数 形态特征 皮尔逊相关系数
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微造型形状对滑动轴承摩擦特性的影响
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作者 权秀敏 陆玉兵 +2 位作者 马辉 徐巧玲 丁林 《湖北理工学院学报》 2024年第2期6-10,33,共6页
利用激光微造型技术在滑动轴承轴颈表面加工出三角形、圆形和正方形微造型,分析不同形状微造型化滑动轴承的摩擦特性,并表征表面形貌,研究表征参数和摩擦特性的关系。结果表明:与未造型的滑动轴承相比,随着载荷增加,微造型后滑动轴承的... 利用激光微造型技术在滑动轴承轴颈表面加工出三角形、圆形和正方形微造型,分析不同形状微造型化滑动轴承的摩擦特性,并表征表面形貌,研究表征参数和摩擦特性的关系。结果表明:与未造型的滑动轴承相比,随着载荷增加,微造型后滑动轴承的摩擦系数逐渐减小,三角形微造型的滑动轴承摩擦系数最小,其次是圆形,最后是正方形。当表面偏态增加,摩擦系数升高,而表面峰态增加时,摩擦系数变化正好相反;当表面谷处和中心处平均空体体积增加时,摩擦系数先降低后升高,表面谷处及中心处平均空体体积分别为6.148×10^(-4)mm^(3)和5.418×10^(-3)mm^(3)时,摩擦系数最低;当表面峰和谷平均体积增加时,摩擦系数降低。在载荷3200 N及600 r/min时,微造型后滑动轴承的摩擦系数随着连通性系数的增加而降低。 展开更多
关键词 微造型形貌 滑动轴承 摩擦特性 表面表征参数 连通性系数
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地热储层岩体粗糙裂隙的热流耦合效应研究
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作者 刘先珊 李宇 +1 位作者 李满 杨欣 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2024年第5期852-862,共11页
为了解决地热开采涉及复杂的多物理场耦合问题,提高开采效率,本文针对开采过程中的渗流-传热问题以离散元软件3DEC构建岩体粗糙裂隙热-流耦合数值模型。考虑不同三维形貌特征的岩体裂隙,模拟水力开度为19.17μm在不同流速时的水-岩温度... 为了解决地热开采涉及复杂的多物理场耦合问题,提高开采效率,本文针对开采过程中的渗流-传热问题以离散元软件3DEC构建岩体粗糙裂隙热-流耦合数值模型。考虑不同三维形貌特征的岩体裂隙,模拟水力开度为19.17μm在不同流速时的水-岩温度变化规律。结果表明:由于裂隙形貌的阻滞作用,粗糙面出水口温度下降较慢,出水口温度有所上升,模型达到稳态所需的时间随流速和对流换热系数的增大而减小。裂隙形貌对流体和岩体温度分布均有影响,粗糙裂隙面的冷锋形态和裂隙面的形貌密切相关。光滑裂隙热突破快于粗糙裂隙,增加裂隙面的粗糙度有助于延长热突破时间。粗糙裂隙面相对于光滑裂隙面的总热量提取率略有提升,流速和对流换热系数的增加显著提高总热量提取率。通过本文研究可以为地热能系统的设计提供重要参数和指导,能够提高地热能开发利用效率。 展开更多
关键词 干热岩 渗流-传热 三维形貌 水力开度 流速 对流换热系数 粗糙裂隙面 热采率 热突破
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14种酢浆草属植物花粉形态及其亲缘关系分析
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作者 陈生煜 唐小云 +3 位作者 肖云 韩茹 翟俊文 吴沙沙 《广西植物》 CAS CSCD 北大核心 2024年第4期682-698,共17页
利用扫描电镜对14种酢浆草属植物花粉形态及表面纹饰进行观测,对其花粉形态进行聚类分析,并基于孢粉学聚类结果,探讨其种间亲缘关系。结果表明:(1)所观测的14种植物花粉粒为近球形或扁球形,极面观均为三裂圆形,多数为3沟花粉粒,稀2沟(... 利用扫描电镜对14种酢浆草属植物花粉形态及表面纹饰进行观测,对其花粉形态进行聚类分析,并基于孢粉学聚类结果,探讨其种间亲缘关系。结果表明:(1)所观测的14种植物花粉粒为近球形或扁球形,极面观均为三裂圆形,多数为3沟花粉粒,稀2沟(星星酢浆草)和4沟(黄花酢浆草);其中,96.3%花粉粒为中等大小,3.7%为小花粉粒;不同花柱类型都表现为长雄蕊花粉比短雄蕊花粉大;外壁纹饰可分为复网状和网状两类。(2)首次发现3种存在异常花粉粒,分别为桃之辉酢浆草、一片心酢浆草及黄花酢浆草,花粉的异常表现为萌发沟数目和排列异常,其外壁纹饰结构与正常花粉粒未有明显不同。(3)根据外壁纹饰可将14种划分为2大类。一类为复网状花粉,仅构巢酢浆草和果香酢浆草为该类纹饰,二者亲缘关系较近。另一类为网状花粉,对12种具网状花粉酢浆草进行聚类分析可划分为4个类型,其中桃之辉酢浆草、双色冰淇淋酢浆草、藤双色冰淇淋酢浆草亲缘关系较近;扁平酢浆草、黄花酢浆草、纳马夸纳酢浆草及兔耳酢浆草亲缘关系较近;大花酢浆草、星星酢浆草、乳白蝴蝶叶酢浆草亲缘关系较近;吉氏酢浆草和一片心酢浆草与其他酢浆草亲缘关系较远。该研究结果表明,花粉形态相近的物种在植株形态上有一定的相似性,花粉形态特征可作为种间亲缘关系研究和分类划分依据,进一步为酢浆草属植物杂交育种亲本选择提供理论基础。 展开更多
关键词 酢浆草属 花粉形态 异型花柱 异常花粉 亲缘关系
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基于核基因组的樟科檬果樟属亚洲类群系统发育关系的重建
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作者 李启少 屈亚亚 +4 位作者 辛雅萱 唐军荣 曹正英 余青富 辛培尧 《中南林业科技大学学报》 CAS CSCD 北大核心 2024年第6期43-55,共13页
【目的】樟科Lauraceae檬果樟属Caryodaphnopsis Airy Shaw植物种子含油量丰富,果实和木材极具开发潜力。由于该属亚洲类群种间差异小、种间关系混乱、现存标本量少,人们对该属植物了解甚少,极大地阻碍了檬果樟属物种的开发利用,因此,... 【目的】樟科Lauraceae檬果樟属Caryodaphnopsis Airy Shaw植物种子含油量丰富,果实和木材极具开发潜力。由于该属亚洲类群种间差异小、种间关系混乱、现存标本量少,人们对该属植物了解甚少,极大地阻碍了檬果樟属物种的开发利用,因此,构建檬果樟属亚洲类群的系统发育关系迫在眉睫。【方法】为了深入了解檬果樟属亚洲类群,采用二代测序技术分别获得44个檬果樟属植物的核糖体基因组(nrG)序列构建高支持的系统发育关系,并综合系统发育结果与形态性状比较论证。【结果】使用nrDNA序列矩阵构建ML树和贝叶斯树,ML树和贝叶斯树的分组完全一致。对比ITS树发现除檬果樟和宽叶檬果樟外的系统发育结构基本一致,老挝檬果樟、缘毛檬果樟和河口檬果樟依然共同聚成在一个大分支下,且宽叶檬果樟和檬果樟2个物种也聚在一起。ITS序列和nrDNA序列树都表明:宽叶檬果樟和檬果樟亲缘关系较近;老挝檬果樟、河口檬果樟和缘毛檬果樟的亲缘关系较近,推测这2个物种之间可能发生过杂交或基因交流。综合形态性状辅助论证,将44个檬果樟属样本分为9组,依次为小花檬果樟C.henryi、赤毛檬果樟C.poilanei、二药室檬果樟C.bilocellata、麻栗坡檬果樟C.malipoensis、宽叶檬果樟C.latifolia、檬果樟C.tonkinensis、河口檬果樟C.hekouensis、缘毛檬果樟C.metallica和老挝檬果樟C.laotica。【结论】研究结果不仅揭示了檬果樟属亚洲类群的种间亲缘关系,还对檬果樟属系统发育关系和性状的研究具有重要的生态意义和经济意义。 展开更多
关键词 檬果樟属 系统发育关系 形态学性状 核糖体基因组(nrG)
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