检索结果-南通市图书馆

THE STRUCTURE OF ASTERBATANOSIDE J FROM ASTER BATANGENSIS

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 1995年第3期6卷 221-224页

作者： shao, y Zhou, BN Lin, LZ Cordell, GA Acad Sinica Shanghai Inst Mat Med Shanghai 200031 Peoples R China Univ Illinois Coll Pharm Dept Med Chem & Pharmacognosy Program Collaborat Res Pharmaceut Sci Chicago IL USA

A new medicagenic acid saponin named asterbatanoside J was isolated from the roots of Aster batangensis. On the basis of chemical and spectral studies especially 2D NMR including COSy, HETCOR, HOHAHA, ROESy and HMBC techniques, its structure has been established as 3-O-beta -D-glucopyranosyl-(1 -->6)-beta -D-glucopyranosyl-2 beta ,3 beta -dihydroxy-olean-12-en-23 alpha ,28-dioic acid-28-O-alpha -L-arabinopyranosyl-(1 -->3)-alpha -L-rhamnopyranosyl-(1 -->2)-beta -D-fucopyranoside.

关键词： ct^

Two New Triterpenoid Saponins from Aster Lingulatus

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 1996年第11期7卷 1005-1008页

作者： Hu, B shao, y Qin, GW Ho, CT Chin, CK Rosen, RT ACAD SINICA SHANGHAI INST MAT MEDSHANGHAI 200031PEOPLES R CHINA RUTGERS STATE UNIV COOK COLLNEW BRUNSWICKNJ 08903

Two new saponins named asterlingulatosides A and B were isolated from the whole plants of Aster lingulatus. Their structures were elucidated by spectral and chemical evidence as 3-O-beta-D-glucopyranosyl-3 beta, 16 alpha-dihydroxyolean-12-en-28-oic acid -28-O-alpha-L-arabinopyranoside and 3-O-beta-D-glucopyranosyl-3 beta,16 alpha-dihydroxyolean-12-en-28-oic acid -28-O-alpha-L-rhamnopyranosyl-(1-->2)- alpha-L-arabinopyranoside respectively. They showed inhibitory activity on DNA synthesis of human leukemia HL-60 cells.

关键词： Lingulatus Two New Triterpenoid Saponins from Aster

Indirect adaptive control for a class of linear time-varying plants

在线全文

学校读者我要写书评

暂无评论

Indirect adaptive control for a class of linear time-varying...

Genetic Differentiation Caused by Chromium Treatment in <i>Leersia hexandra</i>Swartz Revealed by RAPD Analysis

作者： c.j.Zhang c.shao t.y.Chai

The adaptive control issue of a class of linear time-varying plants with uniformly bounded but piecewise Lipschitz continuous parameters is cnsidered. A pole-placement control strategy which allows the plant to be with fast varying parameters is employed,under the condition of the number of discontinuities of the plant parameters being small on average .For the case where plant parameters are partially unknown ,an indirect adaptive conrtol scheme is developed by combining and *** addition,it is shown theoretically that the closed-loop system is stable in .the bounded-input bounded -output sense.A simulation example is also given to show the applicability of the control scheme.

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Open Journal of Soil Science 2014年第10期4卷 366-373页

作者： X. W. Cai y. shao Z. M. Lin College of Earth Science Guilin University of Technology Guilin City China

Randomly amplified polymorphic DNA (RAPD) technique was applied to assess the genetic variations and phylogenetic relationships in genetic differentiation within 4 Chromium-treatment Leersia hexandra. The fresh leaves of Leersia hexandra cultivated on the condition of chrome pollution and exogenous organic acids were used as experimental material. The genomic DNA of Leersia hexandra was extracted by using CTAB method. The results showed that different samples of Leersia hexandra exhibited DNA polymorphism when using the random primer S43, S51and S55 as the primers in the RAPD reaction. One specific DNA band about 1000 bp was found in the sample which treated with 10 mmol/L concentration EDTA when used the S43 primer to RAPD. The obvious differences between different EDTA-treatment levels suggest that EDTA has certain effects on enrichment to heavy metals of Leersia hexandra, it will be more favored to Leersia hexandra accumulation of chromium when EDTA concentration increased.

关键词： Chromium Treatment Genetic Differentiation Randomly Amplified Polymorphic DNA (RAPD) Leersia hexandra Swartz

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

π介子的非对称发射与核媒质态方程

高能物理与核物理 1993年第8期17卷 725-730页

作者：王山刘亦铭刘庆军 J.Jiang D.Keane y.shao S.y.Chu S.y.Fung 哈尔滨工业大学理论物理教研室 Department of Physics Kent State UniversityKentOhio 44242 Department of Physics University of CarliforniaRiversideCa 92521

本文采用VUU模型研究了1.8AGeV Ar^+Pb碰撞中π介子非对称发射携带的核物质态方程信息。指出在靶核旁观者吸收较弱的入射核快度区域,末态π介子的集体运动中保留着同重子集体关联类似的特性,其发射方位角分布的非对称性是对核物质态方... 详细信息

本文采用VUU模型研究了1.8AGeV Ar^+Pb碰撞中π介子非对称发射携带的核物质态方程信息。指出在靶核旁观者吸收较弱的入射核快度区域,末态π介子的集体运动中保留着同重子集体关联类似的特性,其发射方位角分布的非对称性是对核物质态方程敏感的参量。由π介子方位角关联函数方法对Bevalac流光室1.8AGeV Ar^+Pb碰撞实验数据的分析结果和对硬核媒质态方程模型模拟事件的计算相符合。

关键词： π介子非对称发射核物质态方程

Discontinuous crack-bridging model for fracture toughness analysis of nacre

在线全文

学校读者我要写书评

暂无评论

Discontinuous crack-bridging model for fracture toughness an...

碰撞1.2A GeV Ar+KCI中的n粒子横向关联与集体性

The 16th Annual Conference of Hong Kong Society of Theoretical and Applied Mechanics 2012、The 1st Mainland-Hong Kong youth Forum on Mechanics 2012、The 8th Shanghai-Hong Kong Forum on Mechanics and Its Application 2012

作者： y.shao H.P.Zhao X.Q.Feng H.J.Gao Institute of Biomechanics and Medical Engineering Department of Engineering MechanicsTsinghua University Division of Engineering Brown UniversityProvidenceRI 02912USA

Studying the structure-property relation of biological materials can not only provide insight into the physical mechanisms underlying their superior properties and functions but also benefit the design and fabrication of advanced biomimetic *** this paper,we present a microstructure-based fracture mechanics model to investigate the toughening effect due to the crack-bridging mechanism of *** theoretical analysis demonstrates the crucial contribution of this mechanism to the high toughness of *** is found that the fracture toughness of nacre exhibits distinct dependence on the sizes of platelets,and the optimized ranges for the thickness and length of platelets required to achieve higher fracture toughness are *** addition,the effects of such factors as the mechanical properties of the

关键词： Discontinuous crack-bridging model for fracture toughness analysis of nacre

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

高能物理与核物理 1993年第10期17卷 912-917页

作者：刘庆军蒋玉桢王山刘亦铭 J.Jiang D.Kcane y.shao S.y.Fung S.y.Chu 哈尔滨工业大学理论物理教研室 Department of Physics Kent State UniversityKentOhio 44242 Department of Physics University of CaliforniaRiversideCa 92521

我们给出了一种分析集合流的n粒子横向关联函数方法,把对n粒子方位角关联的研究和集体性的计算推广到能够同时利用横向动量大小和方位角信息的情形。对于确定集合流的集体性而言,这种方法比仅仅利用方位角信息的多粒子方位角关联方法更... 详细信息

我们给出了一种分析集合流的n粒子横向关联函数方法,把对n粒子方位角关联的研究和集体性的计算推广到能够同时利用横向动量大小和方位角信息的情形。对于确定集合流的集体性而言,这种方法比仅仅利用方位角信息的多粒子方位角关联方法更为敏感。采用这种新方法,分析了Bevalac流光室1.2AGeV Ar+KCl碰撞中n粒子的横向关联,与蒙特卡罗模拟结果的对比推算了该碰撞中末态粒子的集体性是介于85%～95%之间。

关键词：重离子反应碰撞相关函数集合流

Constraints on holographic QCD phase transitions from PTA observations

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： Song He Li Li Sai Wang shao-Jiang Wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University Max Planck Institute for Gravitational Physics (Albert Einstein Institute) CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

2π干涉学中的多π关联

高能物理与核物理 1993年第1期17卷 49-56页

作者：张卫宁蒋玉桢王山刘亦铭 D. Keane J. Jiang y. shao S. y. Fung S. y. Chu 哈尔滨工业大学理论物理教研室哈尔滨150006 Department of Physics Kent State Universitykentohio44242 Department of Physics University of California

多π事件中多π关联对2π干涉学的影响可以用相关π对取样中的多π关联因子和背景中剩余关联因子的比值来表示。在数据分析中这两种关联因子部分抵消,在π源半径较小,事件π多重数较大时,它们在小相对动量区域的差别变大,多π关联对2π... 详细信息

多π事件中多π关联对2π干涉学的影响可以用相关π对取样中的多π关联因子和背景中剩余关联因子的比值来表示。在数据分析中这两种关联因子部分抵消,在π源半径较小,事件π多重数较大时,它们在小相对动量区域的差别变大,多π关联对2π干涉学结果的影响将变得重要。多π关联因子的分布C_(n-2)(q)能够敏感地反映事件中的多π关联效果。对Bevalac流光室2.1AGeVNe+Pb和1.8AGeVAr+Pb实验数据进行的多π关联因子分析表明,前者事件中的多π关联效果大于后者。

关键词：重离子碰撞 π介子多π关联