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91.
Hiroshi Sekine Masaaki Ohshima Hideki Kurokawa Hiroshi Miura 《Reaction Kinetics and Catalysis Letters》2008,95(1):99-105
The liquid phase hydrogenation of naphthalene was performed in the presence of CO over a commercial Ni/SiO2-Al2O3 catalyst. Naphthalene was hydrogenated even in the presence of CO at elevated temperatures, accompanying the hydrogenation
of CO. Two activation energy values were obtained for the naphthalene hydrogenation depending on the reaction temperature.
FT-IR measurement of the adsorbed CO was also carried out. Hydrogenation of the adsorbed CO created sites active for naphthalene
hydrogenation. 相似文献
92.
In this article, we prove that there does not exist a symmetric transversal design which admits an automorphism group of order 4 acting semiregularly on the point set and the block set. We use an orbit theorem for symmetric transversal designs to prove our result. As a corollary of the result, we prove that there is no projective plane of order 12 admitting a collineation group of order 8. © 2007 Wiley Periodicals, Inc. J Combin Designs 16: 411–430, 2008 相似文献
93.
Masahiko Matsukata Ken-ichi Sawamura Tsutomu Shirai Mitsuko Takada Yasushi Sekine Eiichi Kikuchi 《Journal of membrane science》2008,316(1-2):18-27
Controlling the growth of zeolite crystals on a porous alumina support is essential for preparing a compact zeolite membarne. First, mordenite seed crystals applied on a nonporous -alumina disk were grown and morphological change of mordenite crystals were observed in the course of growth. Then, mordenite membranes were synthesized on a porous -alumina tube under the same conditions employed in the study using the alumina disks. We found that seed crystal growth was widely controllable by changing water content in reaction solution, which resulted in better control of the morphology of mordenite crystals for synthesizing a thin compact mordenite membrane. Separation properties for mordenite membranes were studied in water–hydrogen binary system at 473 K with 10 kPa of water partial pressure, where no capillary condensation was expected in non-zeolitic pores. Separation factor for a mordenite membrane with a few defects was poor; however, a defect-free mordenite membrane prepared under a suitable condition highly separated steam from hydrogen. 相似文献
94.
Mizuta M Banba J Kanamori T Tawarada R Ohkubo A Sekine M Seio K 《Journal of the American Chemical Society》2008,130(30):9622-9623
New nucleotide pairs applicable to formation of DNA triplexes were developed. We designed oligonucleotides incorporating 5-aryl deoxycytidine derivatives (dC5Ars) and cyclic deoxycytidine derivatives, dCPPP and dCPPI, having an expanded aromatic area, as the second strand. As pairing partners, two types of abasic residues (C3: propylene linker, phi: abasic base) were chosen. It was concluded that, when the 5-aryl-modified cytosine bases paired with the abasic sites in TFOs in a space-fitting manner, the stability of the resulting triplexes significantly increased. The recognition of C3 toward dC5Ars was selective because of the stacking interactions between their aromatic part and the nucleobases flanking the abasic site. These results indicate the potential utility of new nucleotide triplets for DNA triplex formation, which might expand the variety of structures and sequences and might be useful for biorelated fields such as DNA nanotechnologies. 相似文献
95.
We synthesized a three-way branched oligodeoxynucleotide (ODN) 30-mer using a new branch unit with acid-labile DMTr and oxidatively cleavable TrS groups as orthogonal protecting groups. The branched ODN was successfully synthesized using 5-[3,5-bis(trifluoromethyl)phenyl]-1H-tetrazole and (2R,8aS)-(+)-(camphorylsulfonyl)oxaziridine as the activator of phosphoramidite units and the oxidizing reagent, respectively. We also found that the TrS group was orthogonal to the Lev, TBDMS, and Fmoc groups. These results indicate the possibility of the synthesis of more complex four- and five-way branched ODNs by the combined use of DMTr, TrS, Lev, TBDMS, and Fmoc groups. 相似文献
96.
Keita Saito Yoshiyuki Tokorodani Chihiro Sakamoto Hiroyuki Kataoka 《Molecules (Basel, Switzerland)》2021,26(19)
The odors and emanations released from the human body can provide important information about the health status of individuals and the presence or absence of diseases. Since these components often emanate from the body surface in very small quantities, a simple sampling and sensitive analytical method is required. In this study, we developed a non-invasive analytical method for the measurement of the body odor component 2-nonenal by headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry by selective ion monitoring. Using a StableFlex PDMS/DVB fiber, 2-nonenal was efficiently extracted and enriched by fiber exposition at 50 °C for 45 min and was separated within 10 min using a DB−1 capillary column. Body odor sample was easily collected by gauze wiping. The limit of detection of 2-nonenal collected in gauze was 22 pg (S/N = 3), and the linearity was obtained in the range of 1–50 ng with a correlation coefficient of 0.991. The method successfully analyzed 2-nonenal in skin emissions and secretions and was applied to the analysis of body odor changes in various lifestyles, including the use of cosmetics, food intake, cigarette smoking, and stress load. 相似文献
97.
T. Sekine M. Konishi H. Kudo K. Tagami S. Uchida 《Journal of Radioanalytical and Nuclear Chemistry》1999,239(3):483-487
A95mTc tracer with an excellent quality was prepared by a simple sublimation method after α-bombardment of niobium metal. Technetium-95m
produced by the93Nb(α,2n)95mTc reaction was separated from the niobium targets in a quartz tube by heating at 1100°C in an oxygen gas flow. Technetium-95m
sublimed as an oxide was deposited on the inner wall of the quartz tube outside an electric furnace, and then collected as
a pertechnetate solution by washing with water. The ICP-MS analysis of the95mTc solution revealed its excellent quality, compared to a95mTc solution prepared from the same targets through a wet chemical separation method and a commercial95mTc solution. With this tracer, the precision of ICP-MS analysis of99Tc in environmental samples are highly improved. 相似文献
98.
N. S. Ishioka H. Matsuoka S. Watanabe A. Osa M. Koizumi T. Kume S. Matsuhashi T. Fujimura A. Tsuji H. Uchida T. Sekine 《Journal of Radioanalytical and Nuclear Chemistry》1999,239(2):417-421
The positron emitters11C,13N and18F and their labeled compounds have been produced for studies on plants using a newly developed positron emitting tracer imaging
system. Although this system covers, at present, a limited area in a plant, the distribution of the positron emitter fed into
the plant can be visualized dynamically. Further development of positron-emitter-labeled compounds is expected to elucidate
the physiological function of plants in vivo. 相似文献
99.
Selective formation of thecis isomer of the nitridotechnetium(V) complex with 2,2′:6′,2″-terpyridine
T. Takayama S. Oshikiri T. Sekine H. Kudo 《Journal of Radioanalytical and Nuclear Chemistry》1999,239(2):397-400
The reaction of [TcNCl2(PPh3)2] with 2,2′:6′,2″-terpyridine producedcis-[TcNCl2(terpy)] selectively. The resulting complexes were characterized by1H NMR and IR spectroscopy. The geometries of thecis andtrans isomers were estimated by theoretical calculations following a density functional method. Thecis isomer is likely more stable than thetrans one with respect to thetrans influence of the nitrido ligand. Furthermore, the behavior of nitridotechnetium complexes in polar solvents was compared
to Os-analogues. 相似文献
100.