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931.
932.
Chemical constituents from Schisandra sphenanthera 总被引:1,自引:0,他引:1
The chemical constituents of the stems of Schisandra sphenanthera are described for the first time. This investigation has resulted in the isolation of a new phenolic glycoside (1), along with seven known compounds. The structure of 1 was assigned by using spectroscopic techniques, including 2D NMR spectra. 相似文献
933.
934.
Xi Chen Juzhou Tao Hui Ma Xinhua Zhao 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(10):i74-i76
A novel compound, vanadium aliovalent substituted zirconium tungstate, ZrW1.8V0.2O7.9, was prepared with vanadium substituting tungsten rather than the common zirconium substitution. The structure of the high‐temperature phase was refined from combined neutron and X‐ray powder diffraction data gathered at 530 K. This phase is the disordered centric modification (space group Pa) and the average crystal structure is similar to that of β‐ZrW2O8. The V atom occupies only a W2 site and charge compensation is achieved through oxygen vacancy, i.e. the oxygen vacancy occurs at only the O4 site. [Atom names follow the established scheme; Evans et al. (1996). Chem. Mater. 8 , 2809–2823.] 相似文献
935.
936.
937.
H. Ai Y.-L. Song F.-G. Tao 《Acta Crystallographica. Section C, Structural Chemistry》1999,55(1):IUC9800080-IUC9800080
938.
Electronic detection of single-base mismatches in DNA with ferrocene-modified probes. 总被引:4,自引:0,他引:4
C J Yu Y Wan H Yowanto J Li C Tao M D James C L Tan G F Blackburn T J Meade 《Journal of the American Chemical Society》2001,123(45):11155-11161
Genotyping and gene-expression monitoring is critical to the study of the association between genetics and drug response (pharmacogenomics) and the association of sequence variation with heritable phenotypes. Recently, we developed an entirely electronic method for the detection of DNA hybridization events by the site-specific incorporation of ferrocenyl derivatives into DNA oligonucleotides. To perform rapid and accurate point mutation detection employing this methodology, two types of metal-containing signaling probes with varying redox potentials are required. In this report we describe a new ferrocene-containing phosphoramidite 9 that provides a range of detectable redox potentials. Using automated DNA/RNA synthesis techniques the two ferrocenyl complexes were inserted at various positions along oligonucleotide probes. Thermal stability analysis of these metal-containing DNA oligonucleotides indicates that incorporation of 9 resulted in no destabilization of the duplex. A mixture of oligonucleotides containing compounds 9 and I was analyzed by alternating current voltammetry (ACV) monitored at the 1st harmonic. The data demonstrate that the two ferrocenyl oligonucleotide derivatives can be distinguished electrochemically. A CMS-DNA array was prepared on an array of gold electrodes on a printed circuit board substrate with a self-assembled mixed monolayer, coupled to an electronic detection system. Experiments for the detection of a single-base match utilizing two signaling probes were carried out. The results demonstrate that rapid and accurate detection of a single-base mismatch can be achieved by using these dual-signaling probes on CMS-DNA chips. 相似文献
939.
A new cirmamic acid monoterpenoid ester, intermedin C (1), was isolated from the aerial parts of Schisandra propinqua vat. intermedia. The structure of 1 was elucidated by spectroscopic methods including extensive 1D and 2D NMR techniques. 相似文献
940.
Single shot ablation of metallic materials of aluminium, titanium alloy (Ti6Al4V) and gold has been studied with 10 picoseconds (ps) laser pulses experimentally and theoretically. The ablation rate variation at high fluence was explained by a simplified predictive model based on critical-point phase separation (CPPS) theory. A comparison between experimental and numerical results inferred that CPPS may well be the dominant ablation mechanism for high fluence laser ablation at 10 ps laser duration. 相似文献