oalib

OALib Journal期刊

ISSN: 2333-9721

费用:99美元

投稿

时间不限

2017 ( 107 )

2016 ( 141 )

2015 ( 1862 )

2014 ( 2788 )

自定义范围…

匹配条件: “LAI Xiang-wei” ,找到相关结果约65045条。
列表显示的所有文章,均可免费获取
第1页/共65045条
每页显示
Ethyl N′-[(E)-4-hydroxybenzylidene]hydrazinecarboxylate at 123 K
Xiang-Wei Cheng
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536808019818
Abstract: The molecule of the title compound, C10H12N2O3, adopts a trans configuration with respect to the C=N bond. The dihedral angle between the benzene ring and the hydrazinecarboxylate plane is 14.6 (1)°. Molecules are linked into a three-dimensional network by O—H...O, N—H...O and C—H...O hydrogen bonds, and by C—H...π interactions.
Methyl N′-[(E)-4-hydroxy-3-methoxybenzylidene]hydrazinecarboxylate
Xiang-Wei Cheng
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536808019788
Abstract: The molecule of the title compound, C10H12N2O4, adopts a trans configuration with respect to the C=N double bond. The dihedral angle between the benzene ring and the hydrazinecarboxylate mean plane is 36.54 (6)°. The molecules are linked into a two-dimensional network by intermolecular O—H...O, N—H...O and O—H...N hydrogen bonds, and by aromatic π–π stacking interactions [ring-centroid separation 3.7689 (9) ].
(E)-Methyl N′-(4-hydroxybenzylidene)hydrazinecarboxylate
Xiang-Wei Cheng
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536808018096
Abstract: In the title compound, C9H10N2O3, the hydroxy group and the C=N—N unit are coplanar with the benzene ring. The benzene rings of inversion-related molecules are stacked with their centroids separated by a distance of 3.7703 (9) , indicating weak π–π interactions. In the crystal structure, C—H...O, O—H...O, N—H...O and C—H...O hydrogen bonds link molecules into a infinite two-dimensional network along the a axis.
2-(1-Adamantyl)-4-bromoanisole at 123 K
Xiang-Wei Cheng
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536808016772
Abstract: In the title compound [systematic name: 2-(1-adamantyl)-4-bromo-1-methoxybenzene], C17H21BrO, two weak intramolecular C—H...O hydrogen bonds influence the molecular conformation. The crystal packing exhibits C—H...π interactions, with a relatively short intermolecular C...Cg contact of 3.568 (5) , where Cg is the centroid of the benzene ring. The crystal studied exhibited inversion twinning.
3-(3-Chloropropyl)-7,8-dimethoxy-1H-3-benzazepin-2(3H)-one at 125 K
Xiang-Wei Cheng
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536808011264
Abstract: In the title compound, C15H18ClNO3, the seven-membered ring has a mirror plane passing through the methylene C atom and bisecting the C=C bond. It adopts a bent conformation, intermediate between the boat and chair forms. Both methoxy groups are coplanar with the attached benzene ring [C—C—O—C = 0.5 (3) and 2.2 (3)°]. In the crystal structure, inversion-related molecules are linked via C—H...O hydrogen bonds and π–π interactions involving the benzene ring [centroid–centroid distance = 3.6393 (12) ].
Methyl N′-[(E)-1-phenylethylidene]hydrazinecarboxylate
Xiang-Wei Cheng
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536808019259
Abstract: The molecule of the title compound, C10H12N2O2, adopts a trans configuration with respect to the C=N bond. The dihedral angle between the phenyl ring and the hydrazine carboxylic acid mean plane is 25.23 (9)°. In the crystal structure, molecules are linked into chains by N—H...O hydrogen bonds and C—H...π interactions.
1-Acetyl-5,6-dimethoxyindoline at 123 K
Xiang-Wei Cheng
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536808017376
Abstract: In the title compound, C12H15NO3, all C, N and O atoms lie in a mirror plane. An intramolecular C—H...O hydrogen bond is present.
3-(3-Chloropropyl)-7,8-dimethoxy-2,3,4,5-tetrahydro-1H-3-benzazepin-2-one at 125 K
Xiang-Wei Cheng
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536808008787
Abstract: In the title compound, C15H20ClNO3, the seven-membered ring adopts a distorted boat–sofa conformation; the methylene C atoms of this ring are coplanar with the benzene ring. Both methoxy groups are almost coplanar with the attached benzene ring [C—C—O—C = 6.5 (2) and 13.5 (3)°]. An intramolecular C—H...O hydrogen bond is observed in the molecular structure. In the crystal structure, a C—H...π interaction involving the benzene ring is observed.
Research of Blind Watermark Detection Algorithm Based on Generalized Gaussian Distribution
Xiang-wei Zhu
Journal of Software , 2010, DOI: 10.4304/jsw.5.4.413-420
Abstract: In digital management, multimedia content and data can easily be used in an illegal way-- being copied, modified and distributed again. Copyright protection, intellectual and material rights protection for authors, owners, buyers, distributors and the authenticity of content are crucial factors in solving an urgent and real problem. In such scenario, digital watermark techniques are emerging as a valid solution. Blind watermark detection is a modern digital watermark technology with outstanding feature. A novel algorithm of Blind Watermark Detection based on Generalized Gaussian Distribution is proposed in this paper. To start with, this paper carries on the statistical analysis to the high frequency sub-band coefficients of wavelet and contourlet transform, then knowing the high frequency sub-band coefficients of wavelet and contourlet transform can be characterized by Generalized Gaussian Distribution. So a blind watermark detection algorithm can be designed according to the method of maximum likelihood estimator. Experimental results demonstrate that the performance of watermark detector is good based on Generalized Gaussian Distribution. The scheme is robust against most attack, so it is very effective and practical.
A Resource Allocation Policy Which can Guarantee the Communication Contention in QoS Limitations under Master/Slave Architecture
Master/Slave结构下可保证边竞争QoS限制的资源分配策略

YANG Juan,LAI Xiang-Wei,QIU Yu-Hui,
杨娟
,赖祥伟,邱玉辉

计算机科学 , 2007,
Abstract: An effective way to enhance the concurrency capability of the distributed system is to appropriately allocate the tasks to the processors. However, it is harder and harder to get the optimal solutions along with the expanding scale of the systems. Althoug
第1页/共65045条
每页显示


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.