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791.
A number of the thieno[3,2‐c][1,8]‐naphthyridin‐4(5H)‐ones are chemoselectively synthesized from 4‐(4′‐aryloxybut‐2′‐ynylthio)‐1‐phenyl‐1,8‐naphthyridin‐2(1H)‐ones in 82–90% yield by the formation of sulfoxide, followed by [2,3] and [3,3]sigmatropic rearrangement and an intramolecular Michael addition. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:87–92, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20234 相似文献
792.
Sheng‐Li Li Anwar Usman Ibrahim A. Razak Hoong‐Kun Fun Jie‐Ying Wu Yu‐Peng Tian Min‐Hua Jiang Zu‐Yao Chen 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(5):m181-m183
In the title compound, [Ni(CH5N3S)2(H2O)2](C4H3O4)2·2H2O, the Ni atom lies on a center of symmetry and is coordinated by N and S atoms from two thiosemicarbazide ligands and the O atoms of two water molecules in a distorted octahedral geometry. In the asymmetric unit, the three components are linked together by one O—H⋯O and two N—H⋯O hydrogen bonds. The packing is built from molecular ribbons parallel to the b direction, stabilized by intramolecular hydrogen bonds, and by one N—H⋯S and two N—H⋯O intermolecular hydrogen bonds. The ribbons are further connected into columns by N—H⋯O interactions and then into a three‐dimensional network by three O—H⋯O hydrogen bonds. 相似文献
793.
Anwar Saeed Niqab Khan Taza Gul Wiyada Kumam Wajdi Alghamdi Poom Kumam 《Molecules (Basel, Switzerland)》2021,26(21)
This research work aims to scrutinize the mathematical model for the hybrid nanofluid flow in a converging and diverging channel. Titanium dioxide and silver are considered as solid nanoparticles while blood is considered a base solvent. The couple-stress fluid model is essentially use to describe the blood flow. Therefore, the couple-stress term was used in the recent study with the existence of a magnetic field and a Darcy–Forchheiner porous medium. The heat absorption/omission and radiation terms were also included in the energy equation for the sustainability of drug delivery. An endeavor was made to link the recent study with the applications of drug delivery. It has already been revealed by the available literature that the combination of with any other metal can destroy cancer cells more effectively than separately. Both the walls are stretchable/shrinkable, whereas flow is caused by a source or sink with α as a converging/diverging parameter. Governing equations were altered into the system of non-linear coupled equations by using the similarity variables. The homotopy analysis method (HAM) was applied to obtain the preferred solution. The influences of the modeled parameters have been calculated and displayed. The confrontation of wall shear stress and hybrid nanofluid flow increased as the couple stress parameter rose, which indicates an improvement in the stability of the base fluid (blood). The percentage (%) increase in the heat transfer rate with the variation of nanoparticle volume fraction was also calculated numerically and discussed theoretically. 相似文献
794.
新疆北部干旱地区鼠类群落空间结构差异的比较研究 总被引:1,自引:0,他引:1
本文我们根据前人的研究并结合自己的调查,对新疆北部干旱地区鼠类群落空间结构差异进行了比较分析.结果表明,准噶尔盆地不同地区鼠类群落可划分为:高山草甸型、山地草原型、原生荒漠型、农田林地型和城市型等.一般高山草甸型以根田鼠为主;山地草原型以草原兔尾鼠、小林姬鼠、灰仓鼠为主;原生荒漠大沙鼠、子午沙鼠为主,梭梭荒漠型以大沙鼠,子午沙鼠为主,柽柳荒漠型以红尾沙鼠为主,跞石荒漠型以五趾跳鼠为主,荒漠草原型以五趾跳鼠、根田鼠为主,农田林地型以根田鼠、小家鼠、小林姬鼠、灰仓鼠为主;城市型以褐家鼠、小家鼠、灰仓鼠为主.同时发现,由于人类开垦经营,当地鼠类群落出现了由原始类型向人工环境的演变.褐家鼠是外来种,它已在不少地区占优势地位,成为当地主要的害鼠. 相似文献
795.
Francisco José Aguilar Troyano Khadijah Anwar Prof. Dr. Fabian Mohr Dr. Guillaume Robert Dr. Adrián Gómez-Suárez 《European journal of organic chemistry》2023,26(7):e202300083
Herein, we present a straightforward strategy for the synthesis of fused heterocycles through a deoxygenative, intramolecular Minisci-type reaction. This approach grants access to complex polycyclic scaffolds in three steps from readily available starting materials, such as chlorinated heteroarenes and 1,3-diols. The use of saccharide derivatives as the starting 1,3-diol motif allows for the synthesis of novel heterocyclic scaffolds with excellent diastereoselectivity and formal retention of configuration at the newly formed C−C bond. 相似文献
796.
Optical Review - This work reported a novel terahertz sensor based on metamaterial absorber. The proposed structure is composed of rectangular metallic resonator made of gold placed above on... 相似文献