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31.
Umakoshi K Yamasaki T Fukuoka A Kawano H Ichikawa M Onishi M 《Inorganic chemistry》2002,41(16):4093-4095
Treatment of pyridine-2-thiol (pytH) with H(2) (60 atm) in the presence of 5-methylpyridine-2-thiolate (5-mpyt)-bridged dinuclear Pt(III), Pt(II), or Pd(II) complexes (1 mol %) in DMF at 150 degrees C for 72 h leads to the formation of pyridine in 3-51% yield. From the (1)H NMR study of the exchange reactions and of the products under D(2) pressure, it is suggested that the catalytic reaction involves bimetallic activation of the pyt ligand followed by the liberation of pyridine and H(2)S. 相似文献
32.
Ohkita M Kawano M Suzuki T Tsuji T 《Chemical communications (Cambridge, England)》2002,(24):3054-3055
The crystallization of 2,4,6-triethynyl-1,3,5-triazine (2) leads to a pi-stacked layered structure of a C(sp)-H...N hydrogen-bonded unique hexagonal network structure, which may be regarded as a supramolecular analogue of a hitherto unknown graphyne network: in-plane intermolecular interactions are short and linear H...N contacts (2.31 and 2.34 A) and the interlayer separation is 3.23 A. 相似文献
33.
R. Pacios A.J. Chatten K. Kawano J.R. Durrant D.D.C. Bradley J. Nelson 《Advanced functional materials》2006,16(16):2117-2126
A study of the photo‐oxidation of films of poly[2‐methoxy‐5‐(3′,7′‐dimethyloctyloxy)‐1,4‐phenylene vinylene] (MDMO‐PPV) blended with [6,6]‐phenyl C61‐butyric acid methyl ester (PCBM), and solar cells based thereon, is presented. Solar‐cell performance is degraded primarily through loss in short‐circuit current density, JSC. The effect of the same photodegradation treatment on the optical‐absorption, charge‐recombination, and charge‐transport properties of the active layer is studied. It is concluded that the loss in JSC is primarily due to a reduction in charge‐carrier mobility, owing to the creation of more deep traps in the polymer during photo‐oxidation. Recombination is slowed down by the degradation and cannot therefore explain the loss in photocurrent. Optical absorption is reduced by photo‐bleaching, but the size of this effect alone is insufficient to explain the loss in device photocurrent. 相似文献
34.
35.
A novel coordination gelator exhibits reversible chromatic and sol-gel phase-transition phenomena triggered by thermal and chemical stimuli. 相似文献
36.
Peter D. Mlynek Masaki Kawano Michael A. Kozee Lawrence F. Dahl 《Journal of Cluster Science》2001,12(1):313-338
Reactions of [Ni6(CO)12]2- (1) with CuBr2 have given rise in small yields (10%) to the first example of a close-packed copper-nickel carbonyl cluster; its formulation as [CuxNi35-x(CO)40]5- (with x=3 or 5) is based upon a low-temperature CCD X-ray crystallographic determination coupled with an elemental analysis and X-ray fluorescence measurements. This air-unstable black pentaanion (2) together with one co-crystallized bromide anion, six [NMe4]+ counterions, and one solvated acetone molecule comprise the crystallographic independent part in a monoclinic unit cell of P21/n symmetry (with Z=4). The geometrically unprecedented 35-atom hcp M(A)2M(B)3Ni30 polyhedron of pseudo-D3h symmetry consists of a central 15-atom equilateral 4M(B)3Ni12 triangle that is capped on both sides by two symmetry-related 10-atom equilateral 3M(A)Ni9 triangles. The 35-atom M(A)2M(B)3Ni30 core is encapsulated by 40 COs, whose connectivities, due to an extra CO ligand on one of the three triangular sides, reduce the pseudo D3h symmetry of the metal core to Cs. An elemental analysis via AA and X-ray fluorescence measurements resulted in Cu/Ni ratios of 3.2/31.8 and 3.7/31.3, respectively, that are consistent with the metal core being either Cu5Ni30 (i.e., M(A)=M(B)=Cu) or Cu3Ni32 (i.e., M(A)=Ni; M(B)=Cu). Several attempts to determine the actual stoichiometry of the metal core by use of electrospray FT/MS/ICR measurements were unsuccessful. The maximum metal-core diameter of 2 is ca. 0.41 nm parallel and 0.85 nm perpendicular to the principal 3-fold axis. 相似文献
37.
Suzuki T. Kawano Y. Nakasha Y. Yamaura S. Takahashi T. Makiyama K. Hirose T. 《Solid-State Circuits, IEEE Journal of》2007,42(3):637-646
A full-rate multiplexer (MUX) with a multiphase clock architecture for over 40 Gbit/s optical communication systems is presented. The 4:1 MUX is comprised of a re-timer based on a D-type flip-flop (DFF) and a clock tree system that uses EXOR-type delay buffers to match its skews well to those of the data. The supply voltage is reduced to -1.5 V by analyzing the voltage allocation. Fabricated in a 0.13-mum InP HEMT technology, a DFF test circuit achieved 75-Gbit/s operation and exhibited performance sufficient to re-time 50-Gbit/s serialized data. The 4:1 MUX measurement results demonstrate successful 50-Gbit/s operation at room temperature, and 40-Gbit/s operation, which has 10-11 error free for 231 - 1 pseudorandom bit stream (PRBS) data, up to an ambient temperature of 90 degrees or down to - 1.24 V of supply voltage. The circuit consumes 450 mW at a - 1.5-V supply and exhibits an output jitter of 283 fs rms at 50-Gbit/s operation. We also propose a multiphase clock generator for a MUX that has a serialization of more than four channels 相似文献
38.
39.
A 5-amino-8-hydroxyquinoline (AHQ)-modified gold nanoparticle (GNP) layer was fabricated on an inner wall of a silica capillary column by alternatively passing a citrate-stabilized GNP solution and an AHQ solution in a repeating fashion. The observations by a field emission scanning electron microscope showed that the thickness of the resulting GNP layer was about 0.15 microm. This column was then used as an open tubular solid-phase extraction column for cadmium, followed by electrothermal atomic absorption spectrometric determination. The detection limit of 0.009 ng ml(-1) was obtained. 相似文献