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Two new secolignans from the roots of Urtica mairei Levi. 被引量:9
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作者 Wei Wang Xing Guo Yan +4 位作者 Li Xin Duan Yuan Zhou Ling Tang Yong Qi Wang Bao Min Feng 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第10期1212-1214,共3页
Two new secolignans (1 and 2) were isolated from the roots of Urtica mairei Levi. The structures of these two compounds were determined on the basis of extensive spectroscopic methods including HR-EI-MS, 1D and 2D N... Two new secolignans (1 and 2) were isolated from the roots of Urtica mairei Levi. The structures of these two compounds were determined on the basis of extensive spectroscopic methods including HR-EI-MS, 1D and 2D NMR experiments. 展开更多
关键词 Urtica mairei levi. Secolignans URTICACEAE
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Some Results on Metric n-Lie Algebras 被引量:5
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作者 Rui Pu BAI Wan Qing WU Zhen Heng LI 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2012年第6期1209-1220,共12页
We study the structure of a metric n-Lie algebra G over the complex field C. Let G = S+R be the Levi decomposition, where T4 is the radical of G and S is a strong semisimple subalgebra of G. Denote by re(G) the num... We study the structure of a metric n-Lie algebra G over the complex field C. Let G = S+R be the Levi decomposition, where T4 is the radical of G and S is a strong semisimple subalgebra of G. Denote by re(G) the number of all minimal ideals of an indecomposable metric n-Lie algebra and R^⊥ the orthogonal complement of R. We obtain the following results. As S-modules, R^⊥ is isomorphic to the dual module of G/R. The dimension of the vector space spanned by all nondegenerate invariant symmetric bilinear forms on G is equal to that of the vector space of certain linear transformations on G; this dimension is greater than or equal to rn(G) + 1. The centralizer of T4 in G is equal to the sum of all minimal ideals; it is the direct sum of R^⊥and the center of G. Finally, G has no strong semisimple ideals if and only if R^⊥ R. 展开更多
关键词 Metric n-Lie algebra minimal ideal metric dimension levi decomposition
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A low-carbon economic dispatch model for electricity market with wind power based on improved ant-lion optimisation algorithm 被引量:2
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作者 Renwu Yan Yihan Lin +1 位作者 Ning Yu Yi Wu 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第1期29-39,共11页
Introducing carbon trading into electricity market can convert carbon dioxide into schedulable resources with economic value.However,the randomness of wind power generation puts forward higher requirements for electri... Introducing carbon trading into electricity market can convert carbon dioxide into schedulable resources with economic value.However,the randomness of wind power generation puts forward higher requirements for electricity market transactions.Therefore,the carbon trading market is introduced into the wind power market,and a new form of low-carbon economic dispatch model is developed.First,the economic dispatch goal of wind power is be considered.It is projected to save money and reduce the cost of power generation for the system.The model includes risk operating costs to account for the impact of wind power output variability on the system,as well as wind farm negative efficiency operating costs to account for the loss caused by wind abandonment.The model also employs carbon trading market metrics to achieve the goal of lowering system carbon emissions,and analyze the impact of different carbon trading prices on the system.A low-carbon economic dispatch model for the wind power market is implemented based on the following two goals.Finally,the solution is optimised using the Ant-lion optimisation method,which combines Levi's flight mechanism and golden sine.The proposed model and algorithm's rationality is proven through the use of cases. 展开更多
关键词 ant-lion optimisation algorithm carbon trading levi flight low-carbon economic dispatch wind power market
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接骨木和贵州金丝桃生理生态特性与喀斯特环境适生性比较 被引量:5
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作者 吴楠 刘海 +2 位作者 罗充 吴沿友 吴明开 《湖北农业科学》 2015年第8期1892-1896,1902,共6页
依据贵州省石漠化现状和植物对喀斯特环境条件的影响,筛选喀斯特生态修复适生植物,通过Li-6400便携式光合测定系统分别测定了接骨木(Sambucus williamsii Hance)、贵州金丝桃(Hypericum kouytcheouense Levl.)2种药用植物的叶片光合作... 依据贵州省石漠化现状和植物对喀斯特环境条件的影响,筛选喀斯特生态修复适生植物,通过Li-6400便携式光合测定系统分别测定了接骨木(Sambucus williamsii Hance)、贵州金丝桃(Hypericum kouytcheouense Levl.)2种药用植物的叶片光合作用日变化特征,并结合植物叶片的叶绿素含量、碳酸酐酶(Carbonic anhydrase,CA)活性、稳定碳同位素δ13C变化范围比较了2种植物在喀斯特生境下的适生能力。结果表明,接骨木对于喀斯特石漠化环境有着更好的适生性。 展开更多
关键词 接骨木(Sambucus williamsii Hance) 贵州金丝桃(Hypericum kouytcheouense levi.) 植物生理 喀斯特环境 生态修复 适生性
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Conservation Laws and Symmetries of the Levi Equation 被引量:2
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作者 ZHANG Jian-Bing JI Jie CHEN Deng-Yuan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第12期1261-1264,共4页
The conservation laws of the Levi equation are presented.Two types of symmetry of the Levi equationhierarchy are deduced.Further it is proved that these symmetries construct an infinite-dimensional Lie algebra.
关键词 levi equation Lax pair conservation law SYMMETRY
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On Polynomial Representations of Lie Algebras 被引量:2
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作者 陈酌 贺龙光 钟德寿 《Northeastern Mathematical Journal》 CSCD 2006年第3期335-348,共14页
We study polynomial representations of finite dimensional (R or C) Lie algebras. As a total classification, we show that there are altogether three types of such nontrivial representations and give their subtle stru... We study polynomial representations of finite dimensional (R or C) Lie algebras. As a total classification, we show that there are altogether three types of such nontrivial representations and give their subtle structures. 展开更多
关键词 Lie algebra POLYNOMIAL MORPHISM levi decomposition
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Representations of Ten-Dimensional Levi Decomposition Lie Algebras
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作者 Narayana Mudiyanselage Pushpamali Sarada Kumari Bandara Gerard Thompson 《Advances in Pure Mathematics》 2022年第4期283-305,共23页
The authors have recently completed a partial classification of the ten-dimensional real Lie algebras that have the non-trivial Levi decomposition, namely, for such algebras whose semi-simple factor is so(3). In the p... The authors have recently completed a partial classification of the ten-dimensional real Lie algebras that have the non-trivial Levi decomposition, namely, for such algebras whose semi-simple factor is so(3). In the present paper, we obtain a matrix representation for each of these Lie algebras. We are able to find such representations by exploiting properties of the radical, principally, when it has a trivial center, in which case we can obtain such a representation by restricting the adjoint representation. Another important subclass of algebras is where the radical has a codimension one abelian nilradical and for which a representation can readily be found. In general, finding matrix representations for abstract Lie algebras is difficult and there is no algorithmic process, nor is it at all easy to program by computer, even for algebras of low dimension. The present paper represents another step in our efforts to find linear representations for all the low dimensional abstract Lie algebras. 展开更多
关键词 levi Decomposition Lie Algebra Lie Algebra Representation R-Representation Ten-Dimensions Representation
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Darboux Transformation and New Multi-Soliton Solutions of the Whitham-Broer-Kaup System 被引量:1
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作者 Tiantian Xu 《Applied Mathematics》 2015年第1期20-27,共8页
Through a variable transformation, the Whitham-Broer-Kaup system is transformed into a parameter Levi system. Based on the Lax pair of the parameter Levi system, the N-fold Darboux transformation with multi-parameters... Through a variable transformation, the Whitham-Broer-Kaup system is transformed into a parameter Levi system. Based on the Lax pair of the parameter Levi system, the N-fold Darboux transformation with multi-parameters is constructed. Then some new explicit solutions for the Whitham-Broer-Kaup system are obtained via the given Darboux transformation. 展开更多
关键词 Whitham-Broer-Kaup Equation levi Parameter System LAX PAIR DARBOUX TRANSFORMATION SOLITON Solutions
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Optimization of Suspension Culture Conditions for Hairy Roots of Aconitum coreanum(Levl.) Raipaics 被引量:1
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作者 Changyu LI Shubo LU +2 位作者 Xiangyi KONG Lili LIU Yingping WANG 《Agricultural Biotechnology》 CAS 2013年第4期5-7,共3页
[ Objective] This study aimed to establish an optimized suspension culture for hairy roots of Aconitum coreanum (Levi.) Raipaics. [ Method ] Hairy root of Aconitum coreanum ( Levl. ) Raipaics A0489 was selected as... [ Objective] This study aimed to establish an optimized suspension culture for hairy roots of Aconitum coreanum (Levi.) Raipaics. [ Method ] Hairy root of Aconitum coreanum ( Levl. ) Raipaics A0489 was selected as experimental material, to screen the optimal medium for suspension culture. [ Result] Aconitum coreanum (Levl.) Raipaics hairy roots showed different growth conditions in various liquid medium; salt concentration, nitrogen content, sugar content, rotation speed and room temperature had great influences on the growth of Aconitum coreanum (Levi.) Raipaics hairy roots. [ Conclusion] The optimal suspension culture system for Aconitum coreanum ( Levi. ) Raipaics hairy roots was established : B5 was used as basic medium, culture temperature was 20℃ under dark conditions, rotation speed was 140 r/m in the first 15 d and 110 r/m in the latter 15 d. 展开更多
关键词 Aconitum coreanum levi.) Raipaics Hairy mot OPTIMIZATION Suspension culture
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q-PSEUDOCONVEX DOMAIN IN γ-COMPLETE MANIFOLD
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作者 陈志华 陆志勤 《Chinese Science Bulletin》 SCIE EI CAS 1990年第5期366-370,共5页
In this article we always assume r+q≤n, otherwise the result is trivial. Now we introduce some definitions and notations.Definition 1. Suppose D is a connected open subset in an n-dimensional complex manifold with C^... In this article we always assume r+q≤n, otherwise the result is trivial. Now we introduce some definitions and notations.Definition 1. Suppose D is a connected open subset in an n-dimensional complex manifold with C^2-boundary. We say function φ is a defining function of if there exists an open neighborhood U of x such that φ: U→R and D ∩ U={y∈M|φ(y)【0}, 展开更多
关键词 r-complete MANIFOLD q-pseudoconvex DOMAIN levi form.
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Inverse Limits in Representations of a Restricted Lie Algebra
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作者 Yu Feng YAO Bin SHU Yi Yang LI 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2012年第12期2463-2474,共12页
Let (g, [p]) be a restricted Lie algebra over an algebraically closed field of characteristic p 〉 O. Then the inverse limits of "higher" reduced enveloping algebras {uxs (g) I s ∈ N} with X running over g* ma... Let (g, [p]) be a restricted Lie algebra over an algebraically closed field of characteristic p 〉 O. Then the inverse limits of "higher" reduced enveloping algebras {uxs (g) I s ∈ N} with X running over g* make representations of g split into different "blocks". In this paper, we study such an infinite- dimensional algebra Ax (g) :=lim Uxs (g) for a given X C g*. A module category equivalence is built between subcategories of U(g)-rnod and Ax(g)-mod. In the case of reductive Lie algebras, (quasi) generalized baby Verma modules and their properties are described. Furthermore, the dimensions of projective covers of simple modules with characters of standard Levi form in the generalized x-reduced module category are precisely determined, and a higher reciprocity in the case of regular nilpotent is obtained, generalizing the ordinary reciprocity. 展开更多
关键词 Restricted Lie algebra reductive Lie algebra inverse limit projective module standard levi form
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Multi-component Levi Hierarchy and Its Multi-component Integrable Coupling System
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作者 XIA Tie-Cheng YOU Fu-Cai ZHAO Wen-Ying 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第6X期990-996,共7页
A simple 3M-dimensional loop algebra X is produced, whose commutation operation defined by us is A1 as simple and straightforward as that in the loop algebra A1. It follows that a general scheme for generating multi-... A simple 3M-dimensional loop algebra X is produced, whose commutation operation defined by us is A1 as simple and straightforward as that in the loop algebra A1. It follows that a general scheme for generating multi-component integrable hierarchy is proposed. By taking advantage of X, a new isospectral problem is established, and then by making use of the Tu scheme the well-known multi-component Levi hierarchy is obtained. Finally, an expanding loop algebra FM of the loop algebra .X is presented, based on the FM, the multi-component integrable coupling system of the multi-component Levi hierarchy is worked out. The method in this paper can be applied to other nonlinear evolution equation hierarchies. 展开更多
关键词 loop algebra multi-component levi hierarchy multi-component integrable coupling system
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FOLIATIONS ON CR MANIFOLD
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作者 韩祖宏 《Science China Mathematics》 SCIE 1992年第6期701-708,共8页
In this paper, we prove that there exist CR foliation and complex foliation on abstractCR manifolds and obtain some properties of these foliations.
关键词 CR MANIFOLD levi FORMS INTEGRABILITY foliation.
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GENERALIZED STRUCTURE OF LAX REPRESENTATIONS FOR NONLINEAR EVOLUTION EQUATION
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作者 乔志军 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1997年第7期671-677,共7页
A new production form for a hierarchy of nonlinear evolution equations (NLEEs) is given in this paper. The form contains productions of isospectral and non-isospectral hierarchy. Under this form a generalized structur... A new production form for a hierarchy of nonlinear evolution equations (NLEEs) is given in this paper. The form contains productions of isospectral and non-isospectral hierarchy. Under this form a generalized structure of Lax representations for the hierarchy of NLEEs is this presented. As a concrete example, the Levi-hierarchy of evolution equations are discussed at the end of this paper. 展开更多
关键词 production form generalized structure levi hierarchy
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服装企业组织碳足迹评价分析 被引量:2
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作者 郭燕 《毛纺科技》 CAS 北大核心 2016年第11期78-82,共5页
以全球知名牛仔裤品牌商李维斯(Levi's)为例,纵观国际服装企业如何进行组织碳足迹评价。李维斯公司自2006年开始进行温室气体排放数据收集和核算,通过对其美洲区机构、全球机构、各类运营环节、及企业各类能耗的组织碳排放量核查和... 以全球知名牛仔裤品牌商李维斯(Levi's)为例,纵观国际服装企业如何进行组织碳足迹评价。李维斯公司自2006年开始进行温室气体排放数据收集和核算,通过对其美洲区机构、全球机构、各类运营环节、及企业各类能耗的组织碳排放量核查和碳足迹评价,了解企业经营活动的主要碳排放源和能耗类型,以采取有效的碳减排措施。文章对李维斯企业组织碳足迹评价分析,为我国服装企业开展相关工作提供参考。 展开更多
关键词 温室气体核查 组织碳足迹 李维斯
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Lignans from Pilea cavaleriei Levl subsp. cavaleriei 被引量:1
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作者 周勇 任恒春 +2 位作者 覃日懂 张庆英 梁鸿 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2014年第6期425-428,共4页
A new lignan glycoside, named (7S,8R,8'R)-(-)-lariciresinol-9-O-a-L-rhamnopyranosyl (1-2) 13-D-glucopyranoside (1),was isolated from the ethanol extract ofPilea cavaleriei Levi subsp, cavaleriei, together wit... A new lignan glycoside, named (7S,8R,8'R)-(-)-lariciresinol-9-O-a-L-rhamnopyranosyl (1-2) 13-D-glucopyranoside (1),was isolated from the ethanol extract ofPilea cavaleriei Levi subsp, cavaleriei, together with 17 known lignans (2-18). The structuresof these compounds were elucidated by extensive spectroscopic analysis, including 1D NMR, 2D NMR and HR-ESI-MS.All the compounds were obtained from the genus Pilea for the first time. 展开更多
关键词 Pilea cavaleriei levi subsp cavaleriei URTICACEAE Lignan glycosides Lignans
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Some Theorems on Leibniz n-Algebras from the Category U_(n)(Lb)
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作者 Min Soo Kim Rustam Turdibaev 《Algebra Colloquium》 SCIE CSCD 2021年第1期155-168,共14页
We study the Leibniz n-algebra U_(n)(L),whose multiplication is defined via the bracket of a Leibniz algebra L as[x1,…,xn]=[x1,[…,[xn−2,[xn−1,xn]]…]].We show that U_(n)(L)is simple if and only if L is a simple Lie ... We study the Leibniz n-algebra U_(n)(L),whose multiplication is defined via the bracket of a Leibniz algebra L as[x1,…,xn]=[x1,[…,[xn−2,[xn−1,xn]]…]].We show that U_(n)(L)is simple if and only if L is a simple Lie algebra.An analog of Levi's theorem for Leibniz algebras in U_(n)(Lb)is established and it is proven that the Leibniz n-kernel of U_(n)(L)for any semisimple Leibniz algebra L is the n-algebra U_(n)(L). 展开更多
关键词 Leibniz n-algebra Leibniz n-kernel simple Leibniz n-algebra levi decomposition
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Levi‘s“概念3系”专卖店配置系统的孕育过程
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《建筑技术及设计》 1996年第4期54-65,共12页
关键词 levi's 商店设计 商场设计 配置系统
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FINITE TYPE CONDITIONS ON REAL HYPERSURFACES WITH ONE DEGENERATE EIGENVALUE
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作者 Wei CHEN Yingxiang CHEN Wanke YIN 《Acta Mathematica Scientia》 SCIE CSCD 2021年第6期1949-1958,共10页
Let M be a smooth pseudoconvex hypersurface in ℂ^(n+1) whose Levi form has at most one degenerate eigenvalue. For any tangent vector field L of type (1, 0), we prove the equality of the commutator type and the Levi fo... Let M be a smooth pseudoconvex hypersurface in ℂ^(n+1) whose Levi form has at most one degenerate eigenvalue. For any tangent vector field L of type (1, 0), we prove the equality of the commutator type and the Levi form type associated to L. We also show that the regular contact type, the commutator type and the Levi form type of the real hypersurface are the same. 展开更多
关键词 pseudoconvex hypersuface finite type levi form holomorphic vector field
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国内外牛仔布部分标准研究
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作者 张瑞霞 《陕西纺织》 2004年第3期18-20,共3页
本文主要对我国出口纯棉牛仔布的检验标准和美国Levi Strauss牛仔布检验标准作一横向比较,并提出相应的建议,以期提高对纺织品的国际意识及竞争能力。
关键词 牛仔布 美国 检验标准 技术指标 疵点 levi Strauss
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