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691.
1 INTRODUCTIONRecently,anumberofderivativesofbenzothiazepinehavebeenpreparedandstudiedfortheirpharmacologicalactivities〔15〕.Inourpreviouswork,wehaveincorporatedtheβlactamringinto1,5benzothiazepinebyreactionof1,5benzothiazepinewithsomeacylchlorid… 相似文献
692.
1 INTRODUCTION With the increasing interest in diode-pumped solid state lasers, researches on more efficient new materials for diode pumping become more important. The double borates are a type of excellent laser gain media, for example, Nd3 -doped RAl… 相似文献
693.
1 INTRODUCTION It has been known that the electron correlation energy of molecular systems was, and still is, one of the most serious bottleneck problems to the chemis- try accuracy of computational quantum chemistry. Since L鰓din[1] gave the definition … 相似文献
694.
1 INTRODUCTION Coordination polymers[1~3] with one-, two- or three-dimensional structure and supramolecular compounds[4, 5] formed by weak interactions, such as hydrogen bonds, Van Der Waals’ forces, short-range exclusion forces, etc., have a variety of possible applications ranging from semicon- ductor to catalysts and potentially valuable pro- perties reminiscent of zeolites. So, considerable increasing attention has been focused on the syn- thesis or building of these coordination po… 相似文献
695.
WANG Yana PAN Zhao-Ruia WANG Zuo-Weia HU Zhengb LI Yi-Zhia ZHENG He-Gena c② a 《结构化学》2006,25(9):1057-1062
1 INTRODUCTION Recently, much attention has been focused on metal- organic coordination polymers for their structural novelty and potentially important applications as advanced materials[1~3]. With the development of crystal engineering and supramolecular chemistry, it is possible to use organic ligands and metal salts to construct metal-organic coordination polymers pos- sessing some specific properties. Furthermore, inve- stigations on coordination complexes containing rare earth ion ha… 相似文献
696.
YU Yuna LIN Li-Rongb① HUANG Rong-Binb a 《结构化学》2006,25(10):1197-1202
1 INTRODUCTION Recently, for the fluorescent properties, Schiff base has been more and more important and widely studied in density optical memories, nonlinear op- tics (NLO), organic light-emitting diodes (OLED), polymer LED and electrogenerated chemilumines- cence (ECL)[1~5]. Thiosemicarbazones are a kind of Schiff bases with thiourea and good ligands easily chelating with transition metal ions. Although they have been studied extensively for a long time due to their chemical and b… 相似文献
697.
1 INTRODUCTION The interaction of water molecules with metal sur- faces plays a vital role in a number of important pro- cesses, such as corrosion, heterogeneous catalysis, electrochemical processes in aqueous solutions, hydrogen production, etc.[1] The structure and pro- perties of water adsorbed on well-defined metal sur- faces have been the subject of numerous experi- mental and theoretical investigations. There have been a number of experimental studies of water on metal surfaces throu… 相似文献
698.
LAI Zhu-Zhia b FU Rui-Biaoa SHENG Tian-Lua LI Ya-Mina HUANG Xi-Hea WU Xin-Taoa② a 《结构化学》2006,25(11):1397-1401
1 INTRODUCTION Many efforts have been devoted to the synthesis of metal organophosphonates during the past three decades because of their rich variety of structural chemistry as well as their practical or potential applications in the areas of adsorption/desorption[1, 2], catalysts[3, 4], meso-/microporous materials[5~7] and intercalation chemistry[8~16]. One encouraging deve- lopment direction is the use of phosphonic acids with bi- and trifunctional groups, such as amino, hydroxyl and… 相似文献
699.
LI Xiao-Honga ZHANG Rui-Zhoub CHENG Xin-Lua YANG Xiang-Donga② a 《结构化学》2006,25(11):1351-1358
1 INTRODUCTION The earliest antibacterial agents used as chemo- therapeutic drugs in the 1920s were synthetic agents, such as sulponamides. Since the discovery of peni- cillin and its entry into clinical use in the 1940s, the field has been dominated over the past 50 years by natural products or their semi-synthetic derivatives. The fluoroquinolones are the only synthetic anti- bacterial agents to rival β-lactams for impact in clinical usage in the antibacterial field. In recent years, … 相似文献