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因子分类法在黑龙江塔河地区地质填图中的应用 被引量:15
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作者 时艳香 郝立波 +1 位作者 陆继龙 纪宏金 《吉林大学学报(地球科学版)》 EI CAS CSCD 北大核心 2008年第5期899-903,共5页
利用因子分类法在黑龙江塔河地区进行地球化学单元识别,根据各单元的理论地球化学意义及其与地质单元的对应关系,进行浅覆盖区地质填图研究。充分提取区域化探资料中的地球化学信息,将研究区识别为具有特定地质、地球化学意义的5个地球... 利用因子分类法在黑龙江塔河地区进行地球化学单元识别,根据各单元的理论地球化学意义及其与地质单元的对应关系,进行浅覆盖区地质填图研究。充分提取区域化探资料中的地球化学信息,将研究区识别为具有特定地质、地球化学意义的5个地球化学单元。其中:Be、Nb、Sn、Y、Rb单元主要反映研究区古生代花岗岩和中生代酸碱性火山岩的分布;Co、TFe、Cr、Ni、V、Ti、MgO单元主要反映研究区早元古代侵入岩、变质岩和古生代基性岩体的分布;SiO2、K2O、Na2O单元反映的地质单元主要为古生代侵入岩、中生代酸碱性火山岩和沉积岩;Al2O3、Li、F单元主要反映中生代火山岩的分布;CaO、Sr、Ba单元反映的是中生代沉积岩,可能与生物沉积作用有关,代表比较稳定的沉积环境。同时,根据不同单元的分布形态和边界走向,识别和推断了研究区的北东、北西、南北及东西向断裂构造。 展开更多
关键词 区域化探资料 因子分类法 地质填图 地球化学单元
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Species concepts and biodiversity in Trichoderma and Hypocrea:from aggregate species to species clusters? 被引量:10
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作者 DRUZHININA Irina KUBICEK Christian P. 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2005年第2期100-112,共13页
Trichoderma/Hypocrea is a genus of soil-borne or wood-decaying fungi containing members important to mankind as producers of industrial enzymes and biocontrol agents against plant pathogens, but also as opportunistic ... Trichoderma/Hypocrea is a genus of soil-borne or wood-decaying fungi containing members important to mankind as producers of industrial enzymes and biocontrol agents against plant pathogens, but also as opportunistic pathogens of immunocompromised humans. Species identification, while essential in view of the controversial properties of taxa ofthis genus, has been problematic by traditional methods. Here we will present a critical survey of the various identification methods in use. In addition,we will present an update on the taxonomy and phylogeny of the 88 taxa (which occur as 14 holomorphs, 49 teleomorphs and 25 anamorphs in nature) of Trichoderma/Hypocrea that have been confirmed by a combination of morphological, physiological and genetic approaches. 展开更多
关键词 TrichodermalHypocrea GENUS Molecular taxonomy-phylogeny
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Research on Tourism Competitiveness of Chinese Island Counties:Based on Factor and Cluster Analysis
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作者 Chai Shousheng Long Chunfeng Gao Teng 《Chinese Journal of Population,Resources and Environment》 2012年第4期30-34,共5页
From the perspective of tourism competitiveness,the paper takes 12 island counties of China as the research object,and applies the method of factor analysis to study their competitiveness.The result shows that Putuo a... From the perspective of tourism competitiveness,the paper takes 12 island counties of China as the research object,and applies the method of factor analysis to study their competitiveness.The result shows that Putuo and Dinghai are more competitive while Pingtan and Nan'ao are less competitive.Finally,the 12 island counties are divided into four styles:first-class competitive county (Putuo),seond-class competitive counties (Dinghai,Yuhuan),third-class competitive counties (Chongming,Daishan,Changdao,Changhai and Shengsi),fourth-class competitive counties (Dongshan,Dongtou,Pingtan and Nan'ao) by cluster analysis.The classification of island counties is to clear their relative position,then to promote their development. 展开更多
关键词 COMPETITIVENESS factor analysis cluster analysis is- land county
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Assessment of phytoplankton class abundance using fluorescence excitation-emission matrix by parallel factor analysis and nonnegative least squares
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作者 苏荣国 陈小娜 +2 位作者 吴珍珍 姚鹏 石晓勇 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第4期878-889,共12页
The feasibility of using fluorescence excitation-emission matrix(EEM) along with parallel factor analysis(PARAFAC) and nonnegative least squares(NNLS) method for the differentiation of phytoplankton taxonomic groups w... The feasibility of using fluorescence excitation-emission matrix(EEM) along with parallel factor analysis(PARAFAC) and nonnegative least squares(NNLS) method for the differentiation of phytoplankton taxonomic groups was investigated. Forty-one phytoplankton species belonging to 28 genera of five divisions were studied. First, the PARAFAC model was applied to EEMs, and 15 fluorescence components were generated. Second, 15 fluorescence components were found to have a strong discriminating capability based on Bayesian discriminant analysis(BDA). Third, all spectra of the fluorescence component compositions for the 41 phytoplankton species were spectrographically sorted into 61 reference spectra using hierarchical cluster analysis(HCA), and then, the reference spectra were used to establish a database. Finally, the phytoplankton taxonomic groups was differentiated by the reference spectra database using the NNLS method. The five phytoplankton groups were differentiated with the correct discrimination ratios(CDRs) of 100% for single-species samples at the division level. The CDRs for the mixtures were above 91% for the dominant phytoplankton species and above 73% for the subdominant phytoplankton species. Sixteen of the 85 field samples collected from the Changjiang River estuary were analyzed by both HPLC-CHEMTAX and the fluorometric technique developed. The results of both methods reveal that Bacillariophyta was the dominant algal group in these 16 samples and that the subdominant algal groups comprised Dinophyta, Chlorophyta and Cryptophyta. The differentiation results by the fluorometric technique were in good agreement with those from HPLC-CHEMTAX. The results indicate that the fluorometric technique could differentiate algal taxonomic groups accurately at the division level. 展开更多
关键词 fluorescence excitation-emission matrix parallel factor analysis nonnegative least squares PHYTOPLANKTON fluorescence components
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