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31.
Tian SX 《The journal of physical chemistry. A》2005,109(20):4428-4430
Dialane anions can be formed via a single three-center two-electron (3c-2e) or two-center one-electron (2c-1e) bond. The 2c-1e bonded anion Al(2)H(6)(-)(D(3)(d)) and the 3c-2e bonded anion Al(2)H(6)(-)(C(s)) have significant thermodynamic stabilities with respect to the neutral Al(2)H(6)(D(2)(h)) and correspond to 0.22 and 0.32 eV of the adiabatic electron affinities, respectively. In particular, the 2c-1e bond plays an essential role in stabilizing the Al(2)H(6)(-)(D(3)(d)) anion. 相似文献
32.
Oxo complex [(1,5-COD)4Pt4(mu3-O)2Cl2](BF4)2 (1) reacts readily with ethylene and norbornylene. The ethylene reaction yields acetaldehyde and a 1:1 mixture of (1,5-COD)Pt(Cl)(CH2CH3) (2) and [(1,5-COD)Pt4(eta3-CH2CHCH(CH3))](BF4) (3), while the norbornylene reaction yields a platinaoxetane complex, the first metallaoxetane to be obtained from the reaction of an oxo complex and an alkene. 相似文献
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35.
阴阳离子型表面活性剂双水相萃取色氨酸衍生物和牛血清白蛋白 总被引:7,自引:0,他引:7
溴化十二烷基三乙胺(C12NE)和十二烷基硫酸钠(SDS)在一定条件下混合可以形成具有清晰界面的两个水相,称为阴阳离子型表面活性剂双水相。作者研究了利用该双水相萃取3种色氨酸衍生物和牛血清白蛋白的可能性.文中采用工作曲线校正扣除表面活性剂背景的影响,萃取结果准确可信。 相似文献
36.
Zhong Jie ZOU Yue Sheng DONG Jun Shan YANG 《中国化学快报》2005,16(11):1484-1486
A new β-carboline alkaloid, 4-(9H-β-carbolin-1-yl)-4-oxobutyric acid and a new derivate of isoferulic acid, (E)-3-(3-hydroxy-4-methoxyphenyl)acrylic acid carboxymethyl ester, were isolated from the roots of Anemone altaica. Their structures were determined on the basis of spectral data. 相似文献
37.
1INTRODUCTIONTheorganicaromaticcarboxylatemetalcom-plexeshavearousedmuchattentionandbeenwidelyinvestigated.However,thestrategyofdesignandsynthesisofthesecomplexesismostlyfocusedonrigidligands,suchasterephthalicacidandbenzenetricarboxylicacid,etc.[1~5].Theassemblyofcom-plexesbyusingflexiblearomaticcarboxylateli-gandsisfarlessdeveloped[6,.Phenylenedioxydia-7]ceticacids(bdoaH2)withbiologicalactivitiesandwideapplicationsinagriculture[8]areafamilyofmultidentateflexibleligandswithversatilebind… 相似文献
38.
用丘氏气提定氮器测定植物中的氮 总被引:1,自引:0,他引:1
研究了用气提滴定法测定植物中氮的条件和方法.实验结果表明,与蒸馏法相比,方法简便安全,结果准确 相似文献
39.
Shan Shan Tang Chang Lu Shao Shou Zhu Li 《中国化学快报》2007,18(4):465-468
Nanofibers of poly(vinyl pyrrolidone) (PVP)/Eu^3+ with diameters of 300-900 nm were prepared by using sol-gel processing and electrospinning technique. The products were characterized by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), and photoluminescence (PL). The results indicated that, Eu^3+ was successfully embedded in the onedimensional hybrid nanofibers, and the PVP/Eu^3+ hybrid nanofibers had favorable photoluminescence properties. 相似文献
40.
Tian SX 《The Journal of chemical physics》2005,123(24):244310
The low-lying conformers of N-/O-methylglycine are studied by ab initio calculations at the B3LYP, MP3, and MP4(SDQ) levels of theory with the aug-cc-pVDZ basis set. The conformers having the intramolecular hydrogen bonds N-H...O=C or O-H...N are more stable than the others. Vertical ionization energies for the valence molecular orbitals of each conformer predicted with the electron propagator theory in the partial third-order quasiparticle approximation are in good agreement with the experimental data available in the literatures. The relative energies of the conformers and comparison between the simulated and the experimental photoelectron spectra demonstrate that there are at least three and two conformers of N- and O-methylglycine, respectively, in the gas-phase experiments. The intramolecular hydrogen bonding O-H...N effects on the molecular electronic structures are discussed for the glycine methyl derivatives, on the basis of the ab initio electronic structure calculations, natural orbital bond, and atoms-in-molecules analyses. The intramolecular hydrogen bonding O-H...N interactions hardly affect the electronic structures of the O-NH2-CH2-C(=O)-O-CH3 and alpha-methylated NH2-CH2-C(CH3)OOH conformers, while the similar intramolecular interactions lead to the significantly lower-energy levels of the highest occupied molecular orbitals for the N-(CH3-NH-CH2-COOH) and beta-methylated (NH2-CH2-CH2-COOH) conformers. 相似文献