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991.
Preliminary communicationPalladium-catalyzed carboxylation of aromatic compounds with carbon dioxide
Hiroshi Sugimoto Itaru Kawata Hiroshi Taniguchi Yuzo Fujiwara 《Journal of organometallic chemistry》1984,266(3):c44-c46
Carbon dioxide has been found to react with aromatic compounds such as benzene, anisole, furane, and thiophene to give aromatic acids in modest yields with palladium(II) salts as catalysts. The addition of t-BuOOH increases the yield. 相似文献
992.
993.
Hiroshi Fukuda 《Experimental Mechanics》1989,29(3):330-335
This paper deals with a new bending test method of advanced composites. Although the conventional three- or four-point bending
is convenient to obtain a bending strength, it has several disadvantages especially for advanced composites. A newly proposed
method is based on a bending by means of axial compression and this method overcomes the above disadvantages.
A set of testing devices was designed and machined, and various kinds of composites were tested. It is made clear that the
new method is suitable especialy for high performance composites such as T800/epoxy. 相似文献
994.
995.
Hiroshi Muramatsu Norio Chiba Tatsuaki Ataka Shinichiro Iwabuchi Naoki Nagatani Eiichi Tamiya Masamichi Fujihira 《Optical Review》1996,3(6):470-474
We have developed a system of scanning near-field optical/atomic force microscopy (SNOM/AFM) for fluorescence imaging and spectroscopy of biomaterials in air and liquid. SNOM/AFM uses a bent optical fiber simultaneously as a dynamic force AFM cantilever and a SNOM probe. Optical resolution of SNOM images shows about 50 nm in an illumination mode for a standard sample of a patterned chromium layer of 20 nm thickness on a quartz glass plate. The SNOM/AFM system contains a photon counting system and polychrometer/ICCD (intensified charge coupled device) system for observation of the fluorescence image and spectrograph of micro areas, respectively. The gene coding to green fluorescence protein (GFP) was cloned in recombinantEscherichia coli (E. coli). Topography, fluorescence image and spectrograph of recombinantE. coli by SNOM/AFM showed a difference in fluorescence in individualE. coli. Fluorescence activity of GFP can thus be used as a convenient indicator of transformation. SNOM/AFM is also applicable to observe immobilizedE. coli on a glass plate in water with a liquid chamber and may allow the viewing of observation of floating organisms. 相似文献
996.
997.
Masaru Matsuo Hiroshi Hattori Shunji Nomura Hiromichi Kawai 《Journal of Polymer Science.Polymer Physics》1976,14(2):223-238
A model relating crystal orientation to the deformation of nylon-6 spherulites under uniaxial stretching is discussed in terms of the orientation distribution functions of reciprocal lattice vectors of crystal planes, such as the (002) and (200) planes. The distribution functions calculated from the model are compared with those obtained from x-ray diffraction experiments. It is found that the crystal a axis and, consequently, the direction of hydrogen bonds within the crystal (α modification) orient parallel to the lamellar axis in the undeformed state, and that the crystal orientation behavior of nylon-6 is much different from that of low-density polyethylene, being characterized by much smaller values of the reorientation parameters of crystallites within orienting lamellae. Moreover, small-angle light scattering for Hv and Vv polarization is also calculated on the basis of the spherulite deformation model by taking the nylon-6 crystal as having orthogonal–biaxial symmetry in optical anisotropy. It is concluded that the Hv scattering can be realized in terms of the proposed model for spherulite deformation by taking into account a considerable contribution of hydrogen bonds to the molecular polarizability, so as to make the polarizability along the crystal a axis larger than that along the b axis. In other words, this conclusion suggests positively birefringent spherulites in the nylon-6 samples studied. 相似文献
998.
999.
Mitsuru Nakayama Hiroshi Yamaoka Shizuko Eguchi Terukiyo Hanafusa Shûichi Hayashi 《Journal of mass spectrometry : JMS》1977,12(6):416-417
For some homochromones, it was confirmed by labelling C-9 with deuterium that the CHO radical expelled from the molecular ion contains either the methine hydrogen or one of the methylene hydrogens of the cyclopropane ring. The origin of the CO group in the expelled CHO radical was also inferred, and a plausible mechanistic interpretation is presented. 相似文献
1000.
Hiroshi Maehara 《Discrete Applied Mathematics》1984,7(1):55-64
For a finite point set in Euclidean n-space, if we connect each pair of points by a line segment whenever the distance between them is less than a certain positive constant, we obtain a space graph in n-space. The sphericity of a graph G is defined to be the minimum number n such that G is isomorphic to a space graph in n-space. In this paper we study the sphericities of graphs and present upper bounds on the sphericity for several types of graphs. 相似文献