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181.
1 INTRODUCTIONResearchonSHGeffecthasbeenonaremarkablepositioninorganicnonlinearoptical(NLO)materialsfield.Theconjugateddelocalizedπelectronspossiblyresultinthesecond-orderNLOpropertyoforganiccompounds,soanumberofnitroanilinederivatives,suchas2-methyl… 相似文献
182.
本文报道了以光学活性乳酸为手性元对目标化合物的所有可能的四个异构体所进行的合成。根据合成样品与天然产物的核磁及旋光数据比较,标题化合物的相对及绝对构型都得以完全确立,其完整结构定为(2S,3S)-4,6-庚二炔-2,3-二醇。 相似文献
183.
a. Lab for Shock Wave Detonation Physics Research Southwest Institute of Fluid Physics P.O.Box - Chengdu Sichuan P.R.China b. Institute of Applied Physics Sichuan Union University Chengdu Sichuan P.R.China c. Current 《原子与分子物理学报》1996,(4)
SHOCKCOMPRESSIONBEHAVIOROFBROMOFORMPengShangqianga,b,cJingFuqiana,bHuJinbiaoa,bGouQingquanba.LabforShockWaveandDetonationPhy... 相似文献
185.
1 INTRODUCTION Although the incorrect assignment of the space groups of crystal structures has been addressed in a number of reports, instances of crystal structures refined in incorrect symmetry turn up even in the recent literature[1~4]. A simple method of space group revision makes use of the published atomic coordinates and temperature factors to simulate the diffraction intensities; the structure is then 搒olved?in the correct space group from the simulated hkl-F2 data[5] and an O… 相似文献
186.
1 INTRODUCTION Nitronyl nitroxide radicals (NITR), stable organic radicals, have played an important role in the design and synthesis of molecular magnetic materials[1, 2]. However, nitronyl nitroxide radicals are poor elec- tron-donor ligands and their coordination ability is limited. Recently, it has led to the development of functionalized nitronyl nitroxide radicals in which a strong coligand is incorporated. Due to the strong coordinate ability of nitrogen atom from pryidinyl ring,… 相似文献
187.
1 INTRODUCTION The determination of structures of adsorbed cya- nide (CN) and cyanate (OCN) on transition metal surfaces is important for understanding their bon- ding and reactivity in catalysis and other surface phenomena[1~4]. During the past decade, the adsorp- tion of CN and CN-containing on transition metal surfaces has received a great deal of attention in both experimental[5~20] and theoretical[1~5, 13, 20~33] inves-tigations, and the previous work about the adsorp- tion of… 相似文献
188.
1 INTRODUCTION Macrocyclic[1~5] and macrobicyclic[6~11] com- pounds and their derivatives are great interesting ligand systems because they are good hosts for metal anions, neutral molecules and organic cation guests. Recently, many ligands in these fields have been rapidly developed and studied. Herein we will report the synthesis, crystal structure and characteri- zation of a novel 42-membered [2+2] macrocyclic compound obtained by the condensation of diethyl- lenetriamine with 4,4-d… 相似文献
189.
1 INTRODUCTION Since Bedard et al. reported microporous tin(IV) sulfides synthesized by hydrothermal method in the presence of organic amine in 1989[1, 2], a number of thiostannates have been synthesized using hydro- or solvothermal techniques with organic amines as tem- plates. The structures of the resulting tin(IV) sulfi- des are related to the types of organic amines. Two- dimensional polyanions of the types of [Sn3S7]2- and [Sn4S9]2-, which are denoted as SnS-1 and SnS-3, respe… 相似文献
190.
1 INTRODUCTION even three-dimensional (3-D) extended solid frame- works in appropriate ways is a major challenge in The syntheses and characterizations of novel po- POMs chemistry. Based on the fact that POMs fra- lyoxometalates (POMs) have currently attached in- meworks with high electronic density can act as un- creasing interest owing to not only enormous variety usually effective ligands to coordinate second tran- of intriguing structural topologies, but also their fas- sition meta… 相似文献