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341.
Katsuhiko Kawakami Yasuhiko Ozaki Toshio Tanaka 《Journal of organometallic chemistry》1974,69(1):151-159
Reaction of carbon diselenide in 3 to 1 molar ratio, and areneselenols in equimolar ratio, with trans-IrCl(CO)(PPPh3)2 and PtL4, gives oxidative addition products, IrCl(CO)CSe2)(PPh3)2, Pt(CSe2)L2, IrHCl(CO)(SeC6H4Me-p)(PPh3)2, and PtH(SeR)L2, respectively (R = Ph and p-MeC6H4; L = PPh3 and PPh2Me). However, reactions of PtL4 with an excess of areneselenols afford bis(arylselenide) complexes Pt(SeR)2L2. The configurations of these complexes are discussed on the basis of their IR and PMR spectra. The carbon diselenide adducts are suggested to have configurations similar to the corresponding carbon disulfide adducts. The platinum hydrides are found to exist as a mixture of cis and trans isomers in solution, both the isomers being labile with regard to dissociative exchange of the tertiary phosphine ligands. The trans configurations of Pt(SeR)2(PPh2Me)2 are unambiguously shown by the virtually coupled triplet pattern of the PPh2Me signals. 相似文献
342.
Ghosh D Ghosh P Tanemura M Haysahi A Hayashi Y Shinji K Miura N Yusop MZ Asaka T 《Chemical communications (Cambridge, England)》2011,47(17):4980-4982
Single-walled carbon nanotubes (SWNTs) have been used successfully to fabricate highly transparent and flexible field emission displays (FEDs). Field emission measurements indicated that SWNTs films have great potential to work as building blocks for next generation transparent and flexible FEDs. 相似文献
343.
Honda K Konishi M Kawai M Yamada A Takahashi Y Hoshino Y Inoue S 《Natural product communications》2012,7(4):459-462
Optically active 1,3-bridged cyclobutanes 10 of the bicyclo[3.1.1]heptane ring system and 1,2-bridged cyclobutanes 11 of the bicyclo[3.2.0]heptane ring system were produced by UV irradiation of alpha,beta,gamma,delta-unsaturated esters 9a and 9c-f. The preference of endo-stereochemistry at C-6 bridged head was observed in cross-adducts 10. On the other hand, irradiation of conjugated dienol 9b led via only parallel cycloaddition to 1,2-bridged cyclobutane 11. 相似文献
344.
Kazuya Takemoto Yoshiki Sakuma Shinichi Hirose Tatsuya Usuki Naoki Yokoyama Toshiyuki Miyazawa Motomu Takatsu Yasuhiko Arakawa 《Physica E: Low-dimensional Systems and Nanostructures》2005,26(1-4):185
We present an optical spectroscopy and photon correlation measurement at telecommunication wavelengths performed on single InAs/InP quantum dots. Two main approaches brought high optical quality: an application of a ‘double-cap’ growth method to metalorganic chemical vapor deposition, and fabrication of a small mesa structure using low-damage wet chemical etching. Sharp and discrete exciton transition lines have been observed on the single quantum dots, which widely cover the spectral range of 1.3–1.55 μm. Using a pulsed excitation source and gated single-photon detection modules, we observed a photon antibunching behavior for an isolated exciton emission line, indicating nonclassical light emission near the wavelength of 1.3 μm. 相似文献
345.
Yasuhiko Arai Hiroyuki Hirai Shunsuke Yokozeki 《Optics and Lasers in Engineering》2008,46(10):733-738
The speckle interferometer based on multi-camera technologies using two cameras is applied to a dynamic measurement. The new speckle interferometer is constructed by a prism array and two cameras. A phenomenon, which a bearing-ball collides against a thin polymer film, is investigated by the proposed interferometer. Then, it is shown that the local maximum deformation of the thin film by the collision is about 1.0 μm. Such a deformation process can precisely be analyzed by this method without any troubles of optical dislocations. In the results, it is confirmed that a large deformation process can be analyzed by accumulating measured results of small deformation in every small continuous analysis. Furthermore, it is estimated that the measurement precision of this method is about 5 nm as experimental results. 相似文献
346.
Measurement of mouse urinary type IV collagen using time-resolved fluoroimmunoassay. 总被引:1,自引:0,他引:1
Michimasa Kobayashi Hiroko Kimura Jie Liao Masaaki Abe Sachiko Hirose Yasuhiko Tomino 《Analytical sciences》2003,19(2):205-210
Urinary level of type IV collagen is an important indicator for early renal dysfunction, but there has been no practical system to measure mouse type IV collagen adaptable to extremely small amounts of urine samples. We developed a highly sensitive time-resolved fluoroimmunoassay (TR-FIA) to measure mouse urinary type IV collagen. Based on the structural features of type IV collagen molecule, dithiothreitol (DTT) was used for pretreatment of the samples. This assay permits measurement of 100 pg/ml type IV collagen in 5 microl urine samples. Urinary levels of type IV collagen derived from 12 samples of two different mouse strains (KK/Ta and BALB/c) were measured using this assay. The results demonstrated very clearly the difference in values of urinary type IV collagen between diabetic mice and non-diabetic mice. Compared with the conventional enzyme-linked immunosorbent assay (ELISA), this method requires far smaller volumes of samples, and is best suited to mouse models in future experiments. 相似文献
347.
Katsuro Anazawa Yasuhiko Kaida Yoshinori Shinomura Takashi Tomiyasu Hayao Sakamoto 《Analytical sciences》2004,20(1):79-84
River water and sediment samples were collected at the same site in a vicinity of an abandoned mine, and the concentrations of major elements and heavy metals were determined. The chemical correlations were observed by principal component analysis (PCA), and the samples were classified by cluster analysis (CA) based on the PCA scores. The PCA results presented a macroscopic viewpoint of covariance structure, i.e., the chemical elements could be classified into three groups: 1) major elements and heavy metals in the river water, 2) Cd, Fe and Mn in the sediments, and 3) Cu and Zn in the sediments. The CA results implied a similarity of chemical compositions in most parts of the study area, except the ranges close to the abandoned copper mine. At the mixing location of mining water with natural river water, major elements and cadmium showed simple physical mixing (conservative mixing). Other heavy metals (Cu, Fe, Mn and Zn) showed the massive precipitation at the mixing event. The PCA structure was mainly interpreted in terms of the mixing process between mining water and diluted natural river water. 相似文献
348.
Air‐Stable Cationic Gold(I) Catalyst Featuring a Z‐Type Ligand: Promoting Enyne Cyclizations 下载免费PDF全文
Dr. Fuyuhiko Inagaki Chiaki Matsumoto Yasuhiko Okada Naoya Maruyama Prof. Dr. Chisato Mukai 《Angewandte Chemie (International ed. in English)》2015,54(3):818-822
An air‐stable cationic AuI complex featuring a Z‐type ligand (boron atom) as a σ‐acceptor was developed for elucidating the effect of B on catalytic reactions. An enyne cyclization in the presence of either [Au→B]+ or [Au]+ showed that [Au→B]+ promotes the reactivity, which enabled the effective construction of not only five‐ and six‐membered rings, but also seven‐membered rings. 相似文献
349.
Extremophilic Polysaccharide for Biosynthesis and Passivation of Gold Nanoparticles and Photothermal Ablation of Cancer Cells 下载免费PDF全文
Sreejith Raveendran Neha Chauhan Vivekanandan Palaninathan Yutaka Nagaoka Yasuhiko Yoshida Toru Maekawa D. Sakthi Kumar 《Particle & Particle Systems Characterization》2015,32(1):54-64
Extremophiles are the group of organisms that are far overlooked for exploring novel biomaterials in the field of material science and bionanotechnology. Extremophilic bacterial‐sulfated exopolysaccharide, mauran (MR), is employed for the bioreduction and passivation of gold nanoparticles (AuNps) to enhance the biocompatibility of AuNps and used for photothermal ablation of cancer cells. Here, various concentrations of MR solution are tested for the reduction of HAuCl4 solution in the presence as well as in the absence of an external reducing agent, to produce mauran‐gold nanoparticles (MRAu Nps). These biocompatible nanocomposites are treated with cancer cell lines under in vitro conditions and NIR irradiated for complete ablation. MRAu Nps‐treated cancer cells on immediate exposure to infrared radiation from a femtosecond pulse laser of operating wavelength 800 nm are subjected to hyperthermia causing cell death. Biocompatible MR stabilization could fairly reduce the cytotoxicity caused by bare AuNps during biomedical applications. Application of a biocompatible polysaccharide from extremophilic bacterial origin for reduction and passivation of AuNps and used for a biomedical purpose is known to be first of its kind in bionanofusion studies. 相似文献
350.
A Bis(phenoxy‐imine)Zr Complex for Ultrahigh‐Molecular‐Weight Amorphous Ethylene/Propylene Copolymer
Seiichi Ishii Junji Saito Sadahiko Matsuura Yasuhiko Suzuki Rieko Furuyama Makoto Mitani Takashi Nakano Norio Kashiwa Terunori Fujita 《Macromolecular rapid communications》2002,23(12):693-697
A new bis(phenoxy‐imine)Zr complex has been developed. This complex in conjunction with iBu3Al/Ph3CB(C6F5)4 at 70°C produces ultrahigh‐molecular‐weight amorphous ethylene/propylene copolymer with a weight‐average molecular weight of 10 200 000 g/mol versus polystyrene standards, which represents the highest molecular weight known for linear, synthetic copolymers to date. 相似文献