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871.
872.
Masao Kato Hiroshi Urabe Yoshinao Oosawa Taro Saito Yukiyoshi Sasaki 《Journal of organometallic chemistry》1976,121(1):81-91
Cationic palladium(II) and platinum(II) complexes with chelate ylides and neutral ligands of the type, [MCl (Y) (L)]+BPh4? (M Pd or Pt; Y bdep or bdmp*; L = 4-methylpyridine, 3,5-dimethylpyrazole, PPh3, PCy3, PMePh2, P(OMe)3, AsPh3 or SbPh3) and [M(bdep) (4-methylpyridine)2] (BPh4)2 (M = Pd or Pt) were prepared and characterized by means of infrared and 1H NMR spectra. 相似文献
873.
Tomoyoshi Chiba Shigeo Asai Weigang Xu Masao Sumita 《Journal of Polymer Science.Polymer Physics》1999,37(6):561-574
Information on the crystalline structure and the properties of poly(butylene‐2,6‐naphthalene dicarboxylate) (PBN) has not been well reported until now, but it is known that there are two different crystal modifications in PBN, as follows: one is formed in isotropic samples by annealing (α form); another appears by annealing with tension (β form). The relation between the crystal modifications and the kinetics of isothermal crystallization for PBN was investigated using in‐situ Fourier transform infrared spectroscopy (FTIR) and wide‐angle X‐ray diffraction (WAXD). The melting behavior of each crystalline form was also studied by means of FTIR and differential scanning calorimetry (DSC) measurements. From the analysis of the melt‐crystallized PBN specimens, the two crystalline forms coexisted in the isotropic samples melt‐crystallized at 230°C, but only the α crystal modification was observed in the films annealed at lower temperatures. In addition, it was revealed that, at 230°C, the β modification was formed only in the primary crystallization process. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 561–574, 1999 相似文献
874.
A green method for the controlled synthesis of aliphatic polymers is presented. The ring-opening polymerizations of cyclic monomers including several lactones, such as caprolactone (CL) or pentadecalactone (PDL), and cyclic anhydride monomers, such as succinic anhydride (SUC) and tetrahydrofuran (THF), catalyzed by a series of metal triflates (trifluoromethanesulfonate) were studied. Aluminum triflate was found to be an advantageous candidate to catalyze the ring-opening polymerization of cyclic monomers. The details of the ring-opening polymerization of CL catalyzed by aluminum triflate were studied. The maximum number average molecular weight (Mn), polydispersity (Mw/Mn) and yield of the obtained poly(-caprolactone) (PCL) at 60 °C for 6 hours were 18,400, 1.94 and 89 wt%, respectively. Those of poly(pentadecalactone) (PPDL) at 100 °C for 6 hours were 12,400, 2.24 and 49 wt%, respectively. The Mn, Mw/Mn and yield of the obtained poly(butylene succinate) (PBS) from SUC and THF at 100 °C for 48 hours were 4,900, 2.03 and 84 wt%, respectively. Furthermore, the mechanism of the polymerization was discussed based on the relationship between the conversion of CL and time. The molecular weight buildup of PCL was linear with a conversion in 50 min before the conversion reached 100 % and with Mw/Mn stabilized at about 1.5. The Mw/Mn of PCL then gradually increased. From these data, a living polymerization with a small transesterification was suggested from the PCL polymerization by aluminum triflate. 相似文献
875.
Modified Newton methods for solving a semismooth reformulation of monotone complementarity problems 总被引:10,自引:0,他引:10
In this paper, we propose a Newton-type method for solving a semismooth reformulation of monotone complementarity problems.
In this method, a direction-finding subproblem, which is a system of linear equations, is uniquely solvable at each iteration.
Moreover, the obtained search direction always affords a direction of sufficient decrease for the merit function defined as
the squared residual for the semismooth equation equivalent to the complementarity problem. We show that the algorithm is
globally convergent under some mild assumptions. Next, by slightly modifying the direction-finding problem, we propose another
Newton-type method, which may be considered a restricted version of the first algorithm. We show that this algorithm has a
superlinear, or possibly quadratic, rate of convergence under suitable assumptions. Finally, some numerical results are presented.
Supported by Research Fellowships of the Japan Society for the Promotion of Science for Young Scientists.
Supported in part by the Scientific Research Grant-in-Aid from the Ministry of Education, Science and Culture, Japan. 相似文献
876.
Machida K Kaneko A Hosogai T Kakuda R Yaoita Y Kikuchi M 《Chemical & pharmaceutical bulletin》2002,50(4):493-497
Five new iridoid glycosides, (8Z)-ligstroside (1), (8Z)-nüzhenide (3), 6'-O-alpha-D-glucopyranosylsyringopicroside (4), 3'-O-beta-D-glucopyranosylsyringopicroside (5) and 4'-O-beta-D-glucopyranosylsyringopicroside (6) were isolated, together with a known one, (8E)-nüzhenide (2), from the leaves of Syringa reticulata. Their structures were established on the basis of chemical and spectral data. Compounds 1 and 3 are the first findings of a (8Z)-oleoside-type secoiridoid. Compound 4 is the first naturally occurring iridoid di-glycoside having an isomaltose. 相似文献
877.
Takeshi Kachi Masao Kubota Shin TsugeKuniyuki Kitagawa Norio Arai 《Microchemical Journal》2002,72(2):155-161
This paper describes a novel measurement technique for in-situ monitoring of the degradation processes of coated C/C composites (carbon fiber-reinforced carbon composites) in combusting fields. The samples tested in this experiment were C/C composites with double coating layers of SiC and glass materials doped with Ca and/or Mg as tracer elements. These samples were exposed in an C2H2/air flame emitted the diatomic molecules, and the light from the Mg-Ca hollow cathode lamp passed through the flame around the sample. The spectrally and spatially resolved images of emission were observed with a spectro CCD camera developed by our group. In this work, two-dimensional atomic absorption spectrometry by using the spectro CCD camera was applied to in-situ monitor the degradation processes of each coating layer and the substrate. The results indicated that the temporal changes in the spatial distribution of atomic absorption caused by Ca and Mg atoms proved to be a good measure for in-situ monitoring of the degradation processes of coated C/C composites in a high temperature flame. 相似文献
878.
Yasoo Itoh Yoshihisa Ueda Masao Sugawara Masamitsu Kataoka Hitoshi Sato Yoshio Umezawa 《Analytical sciences》2006,22(2):219-223
The effects of nitrogenous synergists on the potentiometric responses to divalent transition metal ions were investigated concerning polymeric liquid membranes containing thenoyltrifluoroacetone (Htta) as an ionophore. The tested synergists were pyridine (py) and 4,4'-dioctyl-2,2'-bipyridyl (C8bpy). The potentiometric responses to metal ions, such as Cd2+, Co2+, Ni2+ and Zn2+, were induced by adding the synergists into the liquid membrane systems. The coexistence of Htta and a synergist was necessary for generating the membrane potential. The tta- anion adsorbed at the liquid membrane/solution interface and the complex formation between the synergist and a given metal ion appeared to participate in preferential uptake of metal ions. 相似文献
879.
Masao OndaNorio Okada Yaeko FujitaTsuaki Odaka 《Journal of Molecular Spectroscopy》2002,214(2):129-131
The rotational spectrum of cis-2-chlorophenol was observed from 5 to 12 GHz by molecular beam Fourier transform microwave spectrometer (MB-FTMW). The rotational and quadrupole coupling constants for the 35Cl of the molecule were determined: A=2985.4479(22) MHz, B=1549.8591(3) MHz, C=1020.1915(1) MHz, χaa=−68.2429(83) MHz, χ−=−0.922(20) MHz, χab=−11.4(19) MHz. The quadrupole coupling constants of the chlorine nuclei of cis-2-chlorophenol were nearly equal to that of the chlorobenzenes. We concluded that the electric field gradient of the chlorine atom in cis-2-chlorophenol is similar to that of other chlorobenzenes, although the suggestion of intramolecular hydrogen bonding. 相似文献
880.
Masao Doyama Yoshiaki Kogure Toshikazu Kurihara Ryuichiro Oshima 《Applied Surface Science》2006,252(9):3126-3131
Immediate and near-future plans for transmission positron microscopes being built at KEK, Tsukuba, Japan, are described. The characteristic feature of this project is remolding a commercial electron microscope to a positron microscope. A point source of electrons kept at a negative high voltage is changed to a point source of positrons kept at a high positive voltage. Positional resolution of transmission microscopes should be theoretically the same as electron microscopes. Positron microscopes utilizing trapping of positrons have always positional ambiguity due to the diffusion of positrons. 相似文献