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91.
Tsuyoshi Matsumoto Dr. Yosuke Matsui Mikinao Ito Kazuyuki Tatsumi Prof. Dr. 《化学:亚洲杂志》2008,3(3):607-613
The sulfurization of DmpGeH3 (Dmp=2,6‐dimesitylphenyl) afforded the trinuclear germanium sulfide [DmpGe(μ‐S)]2(μ‐S)2Ge(SH)‐Dmp and a series of polythiadigermabicyclo[x.1.1]alkanes (x=3, 4, 5). The reduction of the S? S bonds of these germabicycloalkanes by NaBH4 at 0 °C afforded the dinuclear mercaptogermane syn‐[DmpGe(SH)(μ‐S)2Ge(SH)‐Dmp] ( 5 ) in good yield. The reaction of [Pd(dppe)Cl2] (dppe=1,2‐bis(diphenylphosphanyl)ethane) and the dilithium salt of 5 prepared in situ by the addition of nBuLi (2 equiv) gave the Ge2PdS4 cluster [DmpGe(μ‐S)]2[(μ‐S)2Pd(dppe)], in which the dithiadigermetanedithiolate is bound to the Pd atom at the two thiolato sulfur atoms. The same reaction with [Pd(PPh3)2Cl2] gave another Ge2PdS4 cluster, [DmpGe(μ‐S)]2[(μ‐S)2Pd(PPh3)], but with the dithiadigermetanedithiolate and the Pd center conjoined through a μ‐S atom between the two germanium atoms in addition to the two thiolato sulfur atoms to form a highly distorted cluster core. The formation of two different types of Ge2PdS4 clusters represents the usefulness of 5 in the synthesis of various polynuclear complexes composed of germanium and transition metals. 相似文献
92.
Controllable photoinduced optical attenuation in a single-mode optical fiber by irradiation of a femtosecond pulse laser 总被引:1,自引:0,他引:1
Novel optical attenuation fibers were fabricated by the irradiation of a focused infrared femtosecond pulsed laser onto the core of a silica glass single-mode optical fiber. Optical attenuation at a wavelength of 1.55 microm proportionally increased with increasing numbers of irradiation points and was controllable under laser irradiation conditions. The single-mode property of the waveguide and the mode-field diameter of the optical fiber were maintained after irradiation of the femtosecond laser. It is suggested that the attenuation results from optical scattering at photoinduced spots formed inside the fiber core. 相似文献
93.
Sato K Yamazoe S Yamamoto R Ohata S Tarui A Omote M Kumadaki I Ando A 《Organic letters》2008,10(12):2405-2408
1,3-Diketones were synthesized from alpha,beta-unsaturated ketones by treatment with acid chlorides and Et(2)Zn in the presence of RhCl(PPh(3))3. This is a very simple and extremely chemoselective reaction to give the adduct at the alpha-position of alpha,beta-unsaturated ketones. 相似文献
94.
Kazuki Nakanishi Yosuke Sato Yayat Ruyat Kazuyuki Hirao 《Journal of Sol-Gel Science and Technology》2003,26(1-3):567-570
Silica gels with hierarchical macropores and mesopores have been prepared by inducing phase separation in the alkoxide-based sol-gel system with an addition of alkyltrimethylammonium salt. Narrowly distributed mesopores were observed in the heat-treated gel samples possibly as a result of supramolecular templating of silica oligomers in the reacting solution. The ionic attractive interaction and hydrophobicity of the attached alkyl group cooperatively determined the phase separation tendency. No indication of long-range order of the mesopores was obtained. 相似文献
95.
Matsumoto T Itakura N Nakaya Y Tatsumi K 《Chemical communications (Cambridge, England)》2011,47(3):1030-1032
A S/SH bridged hetero-dinuclear Ru/Ge complex cation reacted with H(2) to afford the μ-S/μ-H complex. The reaction was considerably slower compared to that of the μ-S/μ-OH complex. Thus, the μ-S/μ-SH and μ-S/μ-OH complexes might provide models for the unready and ready states, respectively, of [NiFe] hydrogenase. 相似文献
96.
Ayako Imai Kenji Mawatari Nobuo Ueno Kazuyuki Sakamoto 《Applied Surface Science》2009,256(4):1156-1159
The thickness-dependent electronic structures of Dy silicide films grown on a Si(1 1 1) surface have been investigated by angle-resolved photoelectron spectroscopy. Two (1×1) periodic bands, both of them cross the Fermi level, have been observed in the silicide films formed by Dy coverages of 1.0 monolayer and below, and more than five () periodic bands have been observed in thicker films. Taking the () periodic structure of Dy atoms in the submonolayer silicide film into account, the periodicity of the two metallic bands indicate that they mainly originate from the orbitals of Si atoms, which form a (1×1) structure. Of the () periodic bands observed in thick films, four of them are well explained by the folding of the (1×1) bands into a () periodicity. Regarding the other band, the three () periodic bands would originate from the electronic states related to the inner Si layers that form a () structure, and the one observed in the 3.0 ML film only might originate from the electron located at the interface between bulk Si and the Dy silicide film. 相似文献
97.
Omata T Takahashi K Hashimoto S Maeda Y Nose K Otsuka-Yao-Matsuo S Kanaori K 《Journal of colloid and interface science》2011,355(2):274-281
A novel synthesis route to organic-capped and colloidal ZnO quantum dots (QDs) has been developed. Specifically, zinc-di-t-butoxide and zinc-di-n-butoxide are hydrolyzed by very dilute water (400-600 mass ppm) in hydrophilic benzylamine and polymerized to ZnO by dehydration and/or a butanol elimination reaction. Growth of the ZnO QDs and exchange of the surface capping ligand from the hydroxyl groups and/or benzylamine to the oleylamine occur by heating the colloidal solution after addition of the oleylamine at 100-180°C. The final ZnO QDs with diameters in the range of 3-7 nm are highly dispersible in various organic solvents. The ZnO QDs exhibit the quantum size effect upon UV emission; it was controlled between 3.39 and 3.54 eV in the present study. The defect-related Vis emission decreased and the UV emission becomes dominant when zinc-di-n-butoxide with a 99.99% zinc purity is used as the starting material. The intensity of the photoluminescence UV emission is 1.5 times higher than that of the Vis emission. 相似文献
98.
99.
[reaction: see text] The Heck reaction is a more efficient and reliable method than previous ones for introducing a C3 unit at the benzyl position for the synthesis of Beraprost. Especially, trialkylated long-chain amines such as (n-C(8)H(17))(3)N and (n-C(12)H(25))(3)N resulted in good yields. This development will be used for the industrial synthesis of Beraprost. 相似文献
100.
Kazuyuki Fukano Eiichi Kageyama 《Journal of polymer science. Part A, Polymer chemistry》1975,13(6):1309-1324
The radiation-induced polymerization of styrene adsorbed on silica gel, white carbon, silicic acid anhydride, zeolite, and activated alumina was carried out to elucidate the effect of properties of inorganic substances on the polymerization. The rate of adsorbed state polymerization on these inorganic substances was very fast in comparison with that of bulk-state polymerization. The amount of unextractable polymer depends on the specific surface area and chemical compositions of these inorganic substances. Inorganic substances which contain aluminum as a component element are more likely to be grafted than those which consist of SiO2 alone. The molecular weight and molecular weight distribution of unextractable polymer and extractable polymer differ from one another in each inorganic substance. In case of silicic acid anhydride, unextractable polymer has smaller molecular weight than extractable polymer. These results suggest that unextractable polymer cannot be extracted due to chemical bonds with the inorganic surface. 相似文献