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Morpho-anatomical characterization of Rhododendron subsessile Rendle,an endangered species of the Cordillera Central Range,Philippines
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作者 Mabel Grace V.Bitayan Starleene S.Cervantes Jones T.Napaldet 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第1期241-247,共7页
Conservation of endangered plant species requires a prerequisite basic knowledge of their taxonomy and ecology.Unfortunately in the Cordillera Central Range,several species have not been studied,even though this area ... Conservation of endangered plant species requires a prerequisite basic knowledge of their taxonomy and ecology.Unfortunately in the Cordillera Central Range,several species have not been studied,even though this area harbors a unique type of vegetation not found in other parts of the Philippines.This study documents the morpho-anatomical characteristics of Rhododendron subsessile Rendle,one of the unique and endangered fl ora in the area.The species exhibits a morphology typical of plants in high elevations,being a hardy shrub with small tough leaves,and showy pink fl owers that rival those of commercial rhododendron species.New fi ndings on the species morphology include a variable number of corolla lobes,stamens and a description of its fruits and seeds.The anatomical features of the species are reported here for the fi rst time.The plant exhibits a typical dicot anatomy with dorsiventral leaves,woody stem and root system with the usual arrangement of periderm followed by secondary phloem,vascular cambium,secondary xylem with vessel elements and pith(in the case of the stem).A unique characteristic was identifi ed as the biseriate upper epidermis of the leaf.Documenting themorphological and anatomical features of the species should prove valuable as input baseline information in formulating measures for its conservation. 展开更多
关键词 TAXONOMY Biodiversity conservation biseriate epidermis Variable stamens
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关于双列有轴笔石的起源及其演化
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作者 李积金 《武夷科学》 1992年第1期291-298,共8页
一、引言早在1938年,布尔曼(Bulman)就论述了双笔石类的起源,至今已有55年的历史。在这半个多世纪里,先后又有不少笔石学者论述这一问题,提出各自的见解。但直到目前为止,尚没有获得令人满意的结果。本文根据有关笔石的笔石体始端发育型... 一、引言早在1938年,布尔曼(Bulman)就论述了双笔石类的起源,至今已有55年的历史。在这半个多世纪里,先后又有不少笔石学者论述这一问题,提出各自的见解。但直到目前为止,尚没有获得令人满意的结果。本文根据有关笔石的笔石体始端发育型式,结合它们在地层上出现的顺序,论述了双笔石类可能的起源及其演化系列。本文是为庆贺敬爱的老师唐仲璋教授从事教育、科研工作六十周年而撰写的,谨以此表达对老师的培育之恩的感谢和崇高敬意。 展开更多
关键词 Origing EVOLUTION biserial axonophorous GRAPTOLITES Exigraptus Maeandrograptus Schmalenseei Paracardiograptus.
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Biserial Incidence Algebras
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作者 HAN Guo-qiang YA O Hai-lou 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第2期244-246,共3页
Let K be an algebraically closed field and A be a finite dimensional algebra over K. In this paper we give a classification of biserial incidence algebras with quiver methods.
关键词 biserial algebras incidence algebras representation type QUIVERS
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The first cohomology group of trivial extensions of special biserial algebras 被引量:6
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作者 XU YungeDepartment of Mathematics & Computer Sciences, Hubei University, Wuhan 430062, China 《Science China Mathematics》 SCIE 2004年第4期578-592,共15页
Given a finite dimensional special biserial algebra A with normed basis we obtain the dimension formulae of the first Hochschild homology groups of A and the vector space Alt(DA). As a consequence, an explicit dimensi... Given a finite dimensional special biserial algebra A with normed basis we obtain the dimension formulae of the first Hochschild homology groups of A and the vector space Alt(DA). As a consequence, an explicit dimension formula of the first Hochschild cohomology group of trivial extension TA = A × DA in terms of the combinatorics of the quiver and relations is determined. 展开更多
关键词 HOCHSCHILD (co)homology TRIVIAL extension SPECIAL biserial algebra.
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Finite-dimensional (*)-serial algebras 被引量:2
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作者 YAO HaiLou & FAN WeiLi College of Applied Science, Beijing University of Technology, Beijing 100124, China 《Science China Mathematics》 SCIE 2010年第12期3049-3056,共8页
Let A be a finite-dimensional associative algebra with identity over a field k. In this paper we introduce the concept of (*)-serial algebras which is a generalization of serial algebras. We investigate the properties... Let A be a finite-dimensional associative algebra with identity over a field k. In this paper we introduce the concept of (*)-serial algebras which is a generalization of serial algebras. We investigate the properties of (*)-serial algebras, and we obtain suficient and necessary conditions for an associative algebra to be (*)-serial. 展开更多
关键词 (*)-serial ALGEBRAS biserial MODULES uniserial MODULES
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Hochschild cohomology of special biserial algebras 被引量:1
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作者 Yun-ge XU Faculty of Mathematics & Computer Science,Hubei University,Wuhan 430062,China 《Science China Mathematics》 SCIE 2007年第8期1117-1128,共12页
Based on a four-term exact sequence,the formulae on the dimensions of the first and the second Hochschild cohomology groups of special biserial algebras with normed bases are obtained in terms of combinatorics.
关键词 special biserial algebra Hochschild cohomology MEDAL 16E40 16G10
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(*)-Serial coalgebras 被引量:1
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作者 Hailou YAO Weili FAN Yanru PING 《Frontiers of Mathematics in China》 SCIE CSCD 2012年第5期955-970,共16页
In this paper, we introduce the notion of (*)-serial coalgebras which is a generalization of serial coalgebras. We investigate the properties of (*)-serial coalgebras and their comodules, and obtain sufficient a... In this paper, we introduce the notion of (*)-serial coalgebras which is a generalization of serial coalgebras. We investigate the properties of (*)-serial coalgebras and their comodules, and obtain sufficient and necessary conditions for a basic coalgebra to be (*)-serial. 展开更多
关键词 COALGEBRA biserial comodule )-serial coalgebra QUIVER
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Distributive Functors
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作者 邓邦明 《Science China Mathematics》 SCIE 1994年第11期1281-1288,共8页
The distributivity of the forgetful functor F and of certain subfunctors of F has been studied.
关键词 forgetful FUNCTOR DISTRIBUTIVE FUNCTOR special biserial ALGEBRA PRIMITIVE V-sequence.
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