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41.
42.
A nonenzymatic glucose sensor with good selectivity for the ascorbic acid oxidation is presented. After the gold polycrystalline electrode was subjected to amalgamation treatment, two advantageous effects were observed. One is the enhancement of the surface roughness and the other is an increase in the catalytic current in the glucose oxidation. Besides the known first effect, the latter provided another advantageous effect in a fabrication of nonenzymatic glucose sensor. Using a gold electrode subjected to amalgamation treatment for 60 s, two calibration curves for glucose oxidation at two different potentials of ?0.1 V and 0.25 V were obtained and compared. At the potential of ?0.1 V, at which no ascorbic acid was oxidized and no interference effect was observed, a current sensitivity of 16 μA cm?2 mM?1 from zero to 10 mM glucose concentration range was obtained. At the other potential of 0.25 V, at which ascorbic acid was easily oxidized, a satisfactory calibration curve with negligible ascorbic acid interference was also obtained together with a more enhanced current sensitivity of 32 μA cm?2 mM?1. 相似文献
43.
ω-Tetrahydropyran-2-ylsulfanylalkylmagnesium chlorides are prepared as Grignard reagents containing protected mercaptoalkyl chains, which are useful for the direct introduction of ω-mercaptoalkyl chains to electrophiles. In order to prove the usefulness of these reagents, they were reacted with buckminsterfullerene (C60) to give 1-(ω-mercaptoalkyl)-1,2-dihydrobuck minsterfullerenes after the deprotection of THP group with TFA. 相似文献
44.
Lei Qiao Chao Zhang Xiang‐Wen Zhang Zi‐Chuan Wang Haolin Yin Zhong‐Ming Sun 《中国化学》2020,38(3):295-304
The polypnictide complexes of rare earth cations have drawn the attention of the scientific community for their uncommon bonding modes and potential applications. Herein, we present a systematic and comprehensive summary on recent advances in the field of rare earth polypnictides, focusing on their synthesis, structures, and reactivities. The structural stabilizing effects imposed by the electropositive rare earth cations as well as the reducing capability of rare earth precursors in the synthesis of these polypnictide complexes are described in this review. We also disscuss in detail the bonding interactions and coordination modes between rare earth cations and polypnictide clusters as well as the similarities and the peculiarity of some structures. 相似文献
45.
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47.
三(2-苯并咪唑亚甲基)胺硝酸镍(Ⅱ)配合物的合成及结构 总被引:5,自引:0,他引:5
三(2-苯并咪唑亚甲基)胺简称NTB与Ni(Ⅱ)的硝酸盐形成配合物C28H35N9O9S2Ni。本文报道其合成,红外光谱及晶体结构。该化合物为三斜晶系,空间P1↑-,a=9.650(3),b=12.716(2),c=14.436A,α=11.46(2),β=91.66(3),γ=97.55(2)°,V=1718(2)A^3,Z=2,F(000)=793,Dc=1.48g/cm^3,Mr=764.1 相似文献
48.
The hydrosilylation reaction of octa(hydrido)silsesquioxane with ω‐halo‐1‐alkenes and other unsaturated substrates allows attachment of 8 long‐chain functionalized alkyls on the cubic Si8O12 skeleton. Pt/C and H2PtCl6 have been adopted as the catalysts, the yields being 74–98% for compounds 2–9 . For terminal alkenes, the hydrosilylation follows the anti‐Markonikov's rule. The morphological state of 2–9 ranges from viscous liquid to crystalline materials. The pyrolysis results indicate that 7 , a material of hard spherical core and soft flexible shell, may likely act as nanometer‐size ball bearings up to more than 400 °C. The X‐ray structure of 9 reveals that the molecule is required to possess a center of symmetry crystallographically. The linear arms on 9 , except for two of them, are virtually all‐trans in conformation, not counting the ω‐C‐Cl bond. 相似文献
49.
Hu H Qiao M Xie F Fan K Lei H Tan D Bao X Lin H Zong B Zhang X 《The journal of physical chemistry. B》2005,109(11):5186-5192
The desulfurization of thiophene on Raney Ni and rapidly quenched skeletal Ni (RQ Ni) has been studied in ultrahigh vacuum (UHV) by X-ray photoelectron spectroscopy (XPS). The Raney Ni or RQ Ni can be approximated as a hydrogen-preadsorbed polycrystalline Ni-alumina composite. It is found that thiophene molecularly adsorbs on Raney Ni or RQ Ni at 103 K. At 173 K, thiophene on alumina is desorbed, while thiophene in direct contact with the metallic Ni in Raney Ni undergoes C-S bond scission, leading to carbonaceous species most probably in the metallocycle-like configuration and atomic sulfur. On RQ Ni, the temperature for thiophene dissociation is about 100 K higher than that on Raney Ni. The lower reactivity of RQ Ni toward thiophene is tentatively attributed to lattice expansion of Ni crystallites in RQ Ni due to rapid quenching. The existence of alumina and hydrogen may block the further cracking of the metallocycle-like species on Raney Ni and RQ Ni at higher temperatures, which has been the dominant reaction pathway on Ni single crystals. By 473 K, the C 1s peak has disappeared, leaving nickel sulfide on the surface. 相似文献
50.
Dinuclear Silylene Bridged Cyclopentadienylrhodiumbis(ethene) Complexes, Photochemical Reaction with Benzene Derivatives, and Selective Inclusion of Methylcyclopentane into the Crystal Lattice of [Me2Si{3-But-C5H3Rh(C2H4)2}2] By reaction of [{(C2H4)2RhCl}2] with Na2[Me2Si(C5H4)2] or with Li2[Me2Si(3-But-C5H3)2] in THF the dinuclear silylene bridged complexes [Me2Si{C5H4Rh(C2H4)2}2] 1 and [Me2Si{3-But-C5H3Rh(C2H4)2}2] 2 , respectively, were synthesized. Due to the asymmetric substitution of the five-membered rings and their hindered rotation around the Si? C axes, 2 is formed as three isomers. The X-ray structure analysis of 2 obtained from hexane reveals the selective inclusion of methylcyclopentane, the content of which in the solvent is about 17%, into the crystal lattice. UV irradiation of 1 in hexane in the presence of benzene causes elimination of the ethene ligands yielding the μ-η3:η3 benzene complex [Me2Si(C5H4Rh2)2C6H6] which cannot be separated from unreacted 1 . However, separation is possible in case of the hexamethylbenzene compound 4 analogous with 3 . 相似文献