化学键的种类分为三种,ionic bonding(离子键),covalent bond(共价键),metallic bond(金属键)。 知识点总结: ionic bonding(离子键)的构成:metal+non-metal 形成过程:electron transfer (电子的转移) (金属失去电子,非金属得到电子) Na原子核外电...
Ionic polymer–metal composites (IPMCs) are one type of wet electroactive polymers that show promising actuating properties in many bio-inspiring underwater robotic applications. In these applications, 3-dimensional kinematic motions are desirable to generate high efficient thrust and maneuverability. Howeve...
They undergo hydrogenolysis by 蟽-bond metathesis and CO insertion driven by the oxophilicity of the metal. They are efficient olefin hydrogenation and polymerization catalysts. Uranocene [U(COT) 2 ] is a green pyrophoric complex, with a perfect sandwich structure, whose stability is provided by ...
The present protocol describes a highly efficient, transition metal and solvent-free one-pot annulation of amines, dialkyl acetylenedicarboxylates and β-nitrostyrene using imidazolium Brønsted acidic ionic liquid for the synthesis of tetrasubstituted pyrroles. A diverse functionalized tetrasubstituted pyrrol...
The only pure covalent bonds occur between identical atoms. Usually, there is some polarity (polar covalent bond) in which the electrons are shared, but spend more time with one atom than the other. Ionic bonds form between a metal and a nonmetal. Covalent bonds form between two nonmetals....
Halometallate and halide ions: nucleophiles in competition for hydrogen bond and halogen bond formation in halopyridinium salts of mixed halide–halometall... The compounds (4-ClpyH)3[PtCl6]Cl (1), (4-XpyH)3[FeCl4]2Cl [X = Cl (2); X = Br (3)] and (3-IpyH)2[AuBr3X]X (...
For this reason, transition metal and organometallic catalysts have almost become the dominant ROP catalytic systems [10,15,16]. Even though metal residuals hamper the use of resulting polymers in biomedical, drug delivery, tissue engineering, and micro-electronics applications [2,[17], [18], [...
关键词: Polarization and depolarization Metal-insulator transitions and other electronic transitions Quantized spin models Charge-density-wave systems DOI: 10.1103/PhysRevB.71.125110 被引量: 21 年份: 2005 收藏 引用 批量引用 报错 分享 全部来源 免费下载 求助全文 APS dx.doi.org AIP arXiv.org (全网...
With the rapid development of the chemical industry, contamination of surface water and groundwater has become an increasing problem [1]. Phenolic compounds, which are toxic and stable in the environment, are recognized as industrial water pollutants receiving increasing concern from authorities [1,2...
The metal-coordinated hydrogen isocyanide in [Cr(CO)5CNH] proved to be an ideal hydrogen-bond former. Its discrete adducts with ethers and cyano complexes are surprisingly stable and some are sublimable (1, [Cr] = Cr(CO)5). According to IR, X-ray structure, and 15NMR investigations, st...