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151.
Some novel beta-biarylacryl ferrocene derivatives were synthesized via Pd-catalytic Suzuki cross-coupling reactions of beta-(2-bromophenyl)acrylferrocene and arylboronic acids. The structures were determined with elemental analyses, IR spectra, and (1)H-NMR spectra. 相似文献
152.
Qi Zhanshun Zhang Pilu Wang Fangding Guo Jingru 《Journal of Radioanalytical and Nuclear Chemistry》1988,125(2):271-280
The distribution of the chemical states of tellurium isotopes produced by252Cf spontaneous fission, collected separately in the matrixes of NaCl, Kl, NaF, CH3COONa·3H2O, Na2SO4 and NaNO3 crystals have been investigated. Two chemical states of tellurium isotopes maintained in these matrixes are Te(IV) and Te(VI). The relationships between the distribution of the chemical states of tellurium isotopes and the produced mode of tellurium, the chemical properties of collection matrixes, the time for collecting fission fragments are studied and the possible mechanism of the interactions of the fission products and the matrixes is discussed. The results show that the distribution of chemical states of tellurium isotopes depends on the chemical properties of the collection matrixes mainly. 相似文献
153.
Two reactions, catalyzed by lactate oxidase (LO) and peroxidase, are initiated by a single injection of the enzymes and the substrate 2,2'-azino-bis(3-ethylene-thiazoline-6-sulfonic acid) (ABTS) into the capillary previously filled with the sample (lactate or lactate-oxalate mixture) and the run buffer containing NADH. The oxidized ABTS product upon reaction with NADH is converted to NAD(+) which is separated and detected in less than 2 min at 266 nm with a sample throughput of 7 min (including wash steps between samples). Simplex trade mark software is used to optimize the enzyme concentrations and reaction temperature. Consumption of the more expensive LO enzyme is only 1.4 x 10(-3) U per assay assuming 27 nL per injection. Linearity is established within the range from 0.0025 to 1 mM with R(2) of 0.9982. Recoveries of lactate from five spiked serum samples averaged 101%. Application of this method for the determination of oxalate as an inhibitor of LO is demonstrated. 相似文献
154.
A series of novel phenoxy-phosphinimine ligands (L): L = 2-(Ph2PNR), 4, 6-(CMe3)2-C6H2OH [2, R = SiMe3; 3, R = Ph] have been prepared in the yield of 65-71%. And bis(phenoxy-phosphinimide) group 4 complexes of the type L2MCl2 [4, M = Ti, R = SiMe3; 5, M = Zr, R = SiMe3; 6, M = Ti, R = Ph; 7, M = Zr, R = Ph] have been synthesized by the reaction of the ligands with TiCl4 and ZrCl4. The structure of complex 7 has been determined by X-ray crystallography. The complexes 4-7 showed inactive to ethylene polymerization in the presence of modified methylaluminoxane (MMAO) and i-Bu3Al/Ph3CB(C6 F5)4. These results should be caused by overdoing the steric congestion around central metal. 相似文献
155.
Wei Xiang Qi‐Shi Song Hong‐Jie Zhang Rong‐Tao Li Zhi Na Han‐Dong Sun 《Helvetica chimica acta》2004,87(11):2842-2847
A new ursane‐type nortriterpenoid, adenanthusone (=(11α,12α)‐4‐demethyl‐11,12‐epoxy‐3,13‐dihydroxy‐2‐oxoursa‐3,20(30)‐diene‐28‐oic acid γ‐lactone; 1 ) was isolated from Isodon adenanthus. Its structure was determined by NMR spectra and X‐ray crystallographic diffraction analysis. The biogenetic implication of the nortriterpene is discussed. 相似文献
156.
157.
158.
Xingang Kong Jiarui Zhang Jianfeng Huang Jiayin Li Yi Qin Ting Zhao Qi Feng 《中国化学快报》2019,30(3):771-774
SnNb2O6 and Sn2Nb2O7 nanosheets were synthetized via microwave assisted hydrothermal method, and innovatively employed as anode materials for lithium-ion battery. Compared with Sn2Nb2O7 and the previously reported pure Sn-based anode materials, the SnNb2O6 electrode exhibited outstanding cycling performance. 相似文献
159.
Synthesis, Structure and Conductivity of the New Charge-transfer Salt (ET)_2(CH_2=CH-CH_2-SO_3)·H_2O
Zhi LIU Qi FANG* Wen Tao YU Min Hua JIANG De Qing ZHANG Dao Ben ZHU State Key Laboratory of Crystal Materials Shandong University Jinan Institute of Chemistry The Chinese Academy of Sciences Beijing 《中国化学快报》2003,14(4)
ET is one of the most famous electron-donor molecules, which forms charge-transfer complexes (abbr. CT-complexes) with various types of counterions. These complexes have received intense attention because a wide range of physical properties such as conductivity and superconductivity1, ferromagnetism2-4 and nonlinear optical properties5 was found in these materials. Although the majority of the ET-based CT-complexes were prepared by combining with inorganic counterions, CT-complexes with o… 相似文献
160.
A new ligand, 2-carboxybenzaldehyde-(4’-hydroxy)benzoylhydrazone(H2L) and its ZnII and NiII complexes have been synthesized and characterized on the basis of elemental analyses, molar conductivities, 1H-NMR, IR spectra and thermal analyses. In addition, DNA-binding properties of these two metal complexes were investigated
using spectrometric titrations, ethidium bromide displacement experiments, and viscosity measurements. The results show that
the two complexes, especially the NiII complex, strongly bind with calf-thymus DNA, presumably via an intercalation mechanism. The intrinsic binding constants of the ZnII and NiII complexes with DNA are 2.46 × 105 and 7.94 × 105
M
−1, respectively. 相似文献