نتایج جستجو برای: تکنیک ring core

تعداد نتایج: 362458  

Journal: :علوم 0

for a fixed positive integer , we say a ring with identity is n-generalized right principally quasi-baer, if for any principal right ideal of , the right annihilator of is generated by an idempotent. this class of rings includes the right principally quasi-baer rings and hence all prime rings. a certain n-generalized principally quasi-baer subring of the matrix ring are studied, and connections...

Journal: :Filomat 2023

Let R be a unital *-ring and let a, b,w ? R. In this paper, we give some new characterizations on w-core inverses in particular, it is shown that invertible if only w(aw)n?1- core for any positive integer n, which case, the representations of inverse w(aw)n?1-core are both presented. We further characterize by Hermitian elements (or projections) units.

2010
Tülin Atmaca Tuan-Dung Nguyen

Metropolitan ring networks are usually used to connect the high speed backbone networks with the high speed access networks. In this paper, we focus on the end-to-end performance of a multi-ring architecture in which metropolitan access networks (MANs) are interconnected by a metropolitan core network. These rings are synchronized and can be interconnected transparently through single access no...

2017
Guohui Zhang Yanyan Geng Yakang Jin Jingyi Shi Kelli McFarland Karl L Magleby Lawrence Salkoff Jianmin Cui

Large conductance Ca2+-activated K+ channels (BK channels) gate open in response to both membrane voltage and intracellular Ca2+ The channel is formed by a central pore-gate domain (PGD), which spans the membrane, plus transmembrane voltage sensors and a cytoplasmic gating ring that acts as a Ca2+ sensor. How these voltage and Ca2+ sensors influence the common activation gate, and interact with...

Journal: :Organic & biomolecular chemistry 2014
Xian-Lei Wang Yun-Yu Lu Jie Wang Xuan Wang He-Quan Yao Guo-Qiang Lin Bing-Feng Sun

The first synthetic attempt commencing from an eight-membered ring to approach the [5.3.1] bicyclic core of vinigrol has demonstrated the feasibility of using the conformational bias of the cyclooctane-ring system to realize highly diastereoselective reactions. The synthetic potential of the newly disclosed access to in/out isomerism may stimulate broader interests.

Journal: :Chemistry 2013
Nathan B Bennett Brian M Stoltz

Access to the bicyclo[5.3.0]decane core found in the daucane and sphenolobane terpenoids via a key enone intermediate enables the enantioselective total syntheses of daucene, daucenal, epoxydaucenal B, and 14-para-anisoyloxydauc-4,8-diene. Central aspects include a catalytic asymmetric alkylation followed by a ring contraction and ring-closing metathesis to generate the five- and seven-membered...

Journal: :Organic letters 2013
Wenbo Xu Shuming Wu Lili Zhou Guangxin Liang

A concise and scalable synthesis of a cis-fused bicyclo[5.3.0]decane ring system has been developed for the total synthesis of echinopines. The core of the natural products was constructed efficiently through an intramolecular 1,3-dipolar cycloaddition and ring contraction strategy.

2010
Bin Cui Yan Jin Fang-Ming Wang Li-Zhuang Chen Guang-Fan Han

In the title compound, C(31)H(25)ClO(3), the central ring of the xanthene core shows a shallow boat conformation, while the outer six-membered rings display envelope conformations. The dihedral angle between the outer aromatic rings is 88.1 (3)° and the dihedral angles between the chloro-benzene ring and the two phenyl rings are 69.5 (2) and 69.6 (2)°.

Journal: :Tetrahedron letters 2009
Mohammad Movassaghi Grazia Piizzi Dustin S Siegel Giovanni Piersanti

Observations concerning the synthesis of the core spirocyclic AB-ring system of illudins using an enyne ring closing metathesis (EYRCM) cascade are discussed. Substituent effects, in addition to optimization of the reaction conditions and the olefin tether for the key EYRCM reaction, are examined.

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید