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881.
H. Matsubara Y. Yamamoto I. Kanazawa T. Iwashita Y. Ito S. Takamura A. Yamaguchi We -Hyo Soe R. Yamamoto 《Hyperfine Interactions》1994,84(1):159-164
We report on the results of depth-profiling experiments of multilayers of Cu-Hf using a slow position beam. Experimental data reveal that the Hf layers contain many open-volume type defects and that there might be thin oxidized Hf that reduces theS parameter in the interfaces between Cu-Hf. 相似文献
882.
Seiji Yamaguchi Yosbihiko Sugioka Miwa Ishida Hajime Yokoyama Yoshiro Hirai 《Journal of heterocyclic chemistry》1997,34(4):1329-1334
Diethyl 5-isopropenyl-4,5-dihydrofuran-2,3-dicarboxylate 1a and methyl 5-isopropenyl-3-methoxy-carbonyl-4,5-dihydrofuran-2-acetate 2a were prepared by cylization of diethyl 2-oxosuccinate or dimethyl 3-oxoglutarate with (E)-1,4-dibromo-2-methyl-2-butene. Their chemical properties were studied. 相似文献
883.
Tadashi Asanuma Hideaki Oikawa Yuuichi Ookawa Wataru Yamasita Mitunori Matsuo Akihiro Yamaguchi 《Journal of polymer science. Part A, Polymer chemistry》1994,32(11):2111-2118
Thermotropic liquid crystal polyimide which has neither an ester linkage nor a carbonate linkage was prepared by the polymerization of 1,2,4,5-benzenetetracarboxylic dianhydride (PMDA) and 1,3-bis[4-(4′-aminophenoxy)cumyl)]benzene (BACB). This polyimide shows the liquid crystal phase at 549-593 K. Mixing this liquid crystal polyimide or copolymerizing BACB decreases the melt viscosity of the thermoplastic polyimide (Aurum). © 1994 John Wiley & Sons, Inc. 相似文献
884.
W. J. Agnew W. Böttger F. Feigl J. M. Kolthoff L. Michaelis S. Yamaguchi A. Martini L. Rosenthaler J. Kapulitzas F. Fröhnke R. Nakaseko Matsuy G. Denigès A. Benedetti-Pichler F. Schneider Hilde Thurnwald L. de Brouckère E. Belcke E. W. Schwartze R. M. Hann J. H. Yoe W. L. Hill J. L. Steenkamp K. Heller P. Krumholz R. Montequi W. H. Hammond R. Ripan G. Lode Fr. Hecht und W. Reich-Rohrwig 《Fresenius' Journal of Analytical Chemistry》1932,88(3-4):128-136
Ohne Zusammenfassung 相似文献
885.
W. J. Agnew W. Böttger F. Feigl J. M. Kolthoff L. Michaelis S. Yamaguchi A. Martini L. Rosenthaler J. Kapulitzas F. Fröhnke R. Nakaseko Matsuy G. Denigès A. Benedetti-Pichler F. Schneider Hilde Thurnwald L. de Brouckère E. Belcke E. W. Schwartze R. M. Hann J. H. Yoe W. L. Hill J. L. Steenkamp K. Heller P. Krumholz R. Montequi W. H. Hammond R. Ripan G. Lode Fr. Hecht W. Reich-Rohrwig 《Analytical and bioanalytical chemistry》1932,88(3-4):128-136
886.
A highly sensitive and simple reversed phase high performance liquid chromatographic (HPLC) method for the quantitative determination of free fatty acids in human serum is presented. The method is based on the direct derivatization of serum fatty acids with 6,7-dimethoxy-1-methyl-2(1H)-quinoxalinone-3-propionylcarboxylic acid hydrazide. The derivatization reaction proceeds in aqueous solution in the presence of pyridine and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide at 37 degrees C. The resulting derivatives are separated within 75 min on a reversed phase column (YMC Pack C8) with a gradient elution of aqueous acetonitrile and detected fluorimetrically. The detection limits are 2.5-5 fmol in a 10 microL injection volume. The sensitivity permits precise determination of free fatty acids in 5 microL serum. The method is simple and is without the conventional liquid-liquid extraction steps of serum fatty acids. 相似文献
887.
888.
A. Uedono S. Watauchi Y. Ujihira L. Wei S. Tanigawa R. Suzuki H. Ohgaki T. Mikado H. Kametani H. Akiyama Y. Yamaguchi M. Koumaru 《Hyperfine Interactions》1993,79(1-4):621-625
Defects in the separation by implanted oxygen (SIMOX) wafers were studied by monoenergetic positron beams. For the as-implanted specimen, vacancies introduced by ion implantation were found to form vacancy-oxygen complexes. After high temperature annealing, a drastic increase in the formation probability of positronium was observed. This suggests an introduction of open-spaces by the formation of an amorphous SiO2. The present investigation shows that positrons provide a nondestructive probe for the detection of defects in SIMOX wafers and microstructures of SiO2. 相似文献
889.
890.
M. Nakano H. Fujita M. Takahata S. Kiribayashi K. Yamaguchi 《International journal of quantum chemistry》2001,84(6):649-659
We investigate the microscopic third‐order nonlinear optical properties, i.e., the second hyperpolarizabilities (γ), of two different sizes of molecular aggregates with a dendritic, i.e., Bethe‐lattice, structure. One possesses a nonfractal structure, while the other has a fractal structure. The aggregate is treated in a two‐exciton model composed of two‐state monomers coupled to each other by the dipole–dipole interaction. The off‐resonant γ of the aggregates are calculated by the numerical Liouville approach, including relaxation effects. The total γ value is partitioned into the contribution of virtual exciton generation, and its spatial contribution to γ is analyzed in relation to the virtual excitation processes in the perturbation theory. It is found that the intermolecular‐interaction effect enhances both one‐ and two‐exciton‐generation contributions, while the relaxation effect reduces those, although the one‐ and two‐exciton‐generation contributions have mutually opposite signs. From the comparison of spatial contributions to γ between the nonfractal and fractal aggregates, an enhancement of the contribution to γ from the periphery to the core is observed in the fractal structure, while such a feature is not observed in the nonfractal structure. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001 相似文献