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181.
Dr. Ya Du Dr. Haishen Yang Chengpu Zhu Michael Ortiz Kenji D. Okochi Prof. Dr. Richard Shoemaker Dr. Yinghua Jin Prof. Dr. Wei Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(23):7959-7963
Alkyne metathesis catalysts composed of molybdenum(VI) propylidyne and multidentate tris(2‐hydroxylbenzyl)methane ligands have been developed, which exhibit excellent stability (remains active in solution for months at room temperature), high activity, and broad functional‐group tolerance. The homodimerization and cyclooligomerization of monopropynyl or dipropynyl substrates, including challenging heterocycle substrates (e.g., pyridine), proceed efficiently at 40–55 °C in a closed system. The ligand structure and catalytic activity relationship has been investigated, which shows that the ortho groups of the multidentate phenol ligands are critical to the stability and activity of such a catalyst system. 相似文献
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迭代目标转换因子分析光度法同时测定钯,铑 总被引:3,自引:0,他引:3
钯,铑二元素于HAc-NaAc缓冲介质中,在表面活性剂Triton X-100存在下与5-Br-PADAP形成灵敏度较高的紫红色络合物,其摩尔吸光系数分别为ε565^pd=1.44×10^5,ε562^Rh=1.17×10^5(L·mol^-1·cm^-1)。二元素络合物吸收光谱发生严重重叠。本文探讨了在上述体系中同时测定Pd,Rh的最佳条件,并采用迭代目标转换因子分析法(ITTFA)对Pd,Rh 相似文献
184.
1μm高速CMOS容错时钟接收器电路的研制 总被引:1,自引:0,他引:1
采用新的设计规则与先进的自对准硅化钛LDD CMOS工艺,研制成功了相当于1386主频的1μm、25MHz高速容错时钟接收器电路. 相似文献
185.
The degenerate four wave mixing experiments have been performed in the N, N-dimethylformamide solutions of 3, 4, 9, 10-Tetramethylperylene (TMP) · AsF_6 and (TMP) · PF_6, respectively. The result showed that the two complexes have large nonlinear optical response. 相似文献
186.
根据CAPP系统中对工艺表示及工艺存储的科学合理性要求,结合我国机械制造企业的生产现状,提出一种实用的工艺编码系统,并应用于宁波动力机厂中小型回转体类零件的CAPP系统中。 相似文献
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Selective functionalization of In2O3 nanowire mat devices for biosensing applications 总被引:2,自引:0,他引:2
Curreli M Li C Sun Y Lei B Gundersen MA Thompson ME Zhou C 《Journal of the American Chemical Society》2005,127(19):6922-6923
A strategy to covalently attach biological molecules to the electrochemically active surface of indium oxide nanowire (In2O3 NW) mat devices is presented. A self-assembled monolayer (SAM) of 4-(1,4-dihydroxybenzene)butyl phosphonic acid (HQ-PA) was generated on an indium tin oxide (ITO)-coated glass and In2O3 NWs surface. The chemical steps required for surface derivatization were optimized on an ITO surface prior to modifying the In2O3 NWs. The hydroquinone group contained in the HQ-PA SAM was electrochemically oxidized to quinone (Q-PA) at +330 mV. The monolayer of Q-PA was allowed to react with a thiol-terminated DNA. The DNA was paired to its complementary strand tagged with a fluorescence dye. Attachment of DNA was verified using fluorescence microscopy. A device was subsequently prepared on a SiO2-supported mat of In2O3 NWs by depositing gold electrodes on the mat surface. The reaction strategy optimized on ITO was applied to this In2O3 NW-based device. Arrays of In2O3 NWs on a single substrate were electrochemically activated in a selective manner to Q-PA. Activated In2O3 NWs underwent reaction with HS-DNA and gave a positive fluorescence response after pairing with the dye-DNA. The unactivated In2O3 NWs gave no response, thus demonstrating selective functionalization of an In2O3 NW array. This can be considered a key step for the future fabrication of large-scale, inexpensive, nanoscale biosensors. 相似文献