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241.
The quantum theory of gravitational fields is formulated in a manifestly Lorentz covariant manner in the framework of indefinite-metric quantum field theory. The physical state subspace is defined by the two subsidiary conditions QB|phys〉 = Qc|phys〉 = 0, where the conserved charges QB and Qc are the generators of the BRS transformation ond of the Faddeev-Popov ghost scale transformation, respectively. By clarifying the metric structures of the Fock space of asymptotic fields with help of the Ward-Takahashi identities, the physical S-matrix unitarity is established in just the same way as in the canonical theory of Yang-Mills fields. 相似文献
242.
The reactions of polyfluoroalkyl halides with allylsilanes catalyzed by iron or ruthenium carbonyl complexes give 3-polyfluoroalkylprop-1-enes in good yields under mild conditions. 相似文献
243.
Ai Ito Yuki Asami Marino Asato Kazuo Fukuda Ryu Yamasaki Iwao Okamoto 《Tetrahedron letters》2018,59(25):2454-2458
The cis-trans conformational equilibrium of amides is of interest because it can be used to control functional activity. Here, we designed and synthesized a series of N-(3-thienyl)amides in order to study the factors affecting their conformational equilibrium. NMR studies showed that the major conformer of N-methyl-N-(3-thienyl)amide in solution is the E-form (cis form), as is the case for N-methylacetamide. For N-aryl-N-(3-thienyl)amides bearing an N-phenyl moiety, the major conformers differ depending on not only the relative π-electron density of the N-aryl moiety, but also its size. X-ray analysis showed that their solid-state conformational preferences were similar to those in solution. 相似文献
244.
Journal of Algebraic Combinatorics - We present the characteristic polynomial for the transition matrix of a vertex-face walk on a graph, and obtain its spectra. Furthermore, we express the... 相似文献
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247.
Yuko Fukuyama Teruyo Ojima‐Kato Satomi Nagai Keisuke Shima Shinji Funatsu Yoshihiro Yamada Hiroto Tamura Shizuo Nomura Koretsugu Ogata Sadanori Sekiya Shinichi Iwamoto Koichi Tanaka 《Journal of mass spectrometry : JMS》2019,54(12):966-975
The rapid identification and classification of pathogenic microorganisms, including Salmonella enterica, is important for the surveillance and prevention of foodborne diseases. Matrix‐assisted laser desorption\ionization time‐of‐flight mass spectrometry (MALDI‐TOFMS) has been shown to be an effective tool for the rapid identification of microorganisms. In a previous report, a mass database consisting of 12 biomarker proteins, S8, L15, L17, L21, L25, S7, superoxide dismutase (SodA), peptidylprolyl cis‐trans isomerase C, Gns, YibT, YaiA, and YciF, was introduced for the serotyping of S. enterica via MALDI‐MS (Applied Microbiology and Biotechnology, 2017, 101, 8557‐8569). However, the reproducibility of peak detection of biomarkers such as SodA at m\z 23 000 was poor. We report here an optimized MALDI‐MS method for detecting these biomarkers with high sensitivity and reproducibility. The issue was solved by controlling the bacterial concentration at 1 × 10 to 1 × 102 MFU (3 × 106 to 3 × 107 CFU\μL, as calculated from the MFU), using the colony suspension supernatant obtained by centrifugation, and using matrix additives such as methylenediphosphonic acid and N‐decyl‐β‐D‐maltopyranoside. We propose that the method including the above steps is one of the best for detecting biomarkers with high sensitivity and reproducibility. 相似文献
248.
Yuji Baba Tetsuhiro Sekiguchi Iwao Shimoyama Mitsunori Honda Norie Hirao Ayumi Narita Juzhi Deng 《Surface science》2009,603(16):2612-2618
The morphology, electronic structure and ordering of the phthalocyanine thin films have been investigated at nanometer scale by photoelectron emission microscopy (PEEM) excited by polarized soft X-rays from synchrotron light source. The sample investigated was micropattern of silicon phthalocyanine deposited on gold surface. The incident angle dependences of the X-ray absorption near edge structure (XANES) spectra at the silicon K-edge revealed that the molecules of 5-layered films are lying nearly flat on the surface. Clear image of the micropattern was observed by PEEM, showing that the molecules are deposited via Volmer–Weber (VW) mode at room temperature. While, the surface diffusion was observed upon heating, and the micropattern image almost disappeared at 240 °C, representing the deposition mode changes from VW-mode to Frank–van der Merwe (FM)-one. On the basis of the photon-energy dependences of the brightnesses in the PEEM images, it was found that the molecules diffusing to the fresh gold surface rather stand-up at 240 °C. The observed changes in the molecular orientations at nanometer domains are discussed on the basis of the strengths of the molecule–molecule and molecule–surface interactions. 相似文献
249.
A closed-form integral for the Arrhenius exponential was obtained by using an approximate relation instead of the usual one in a linear temperature program. The closed-form integral can be applied to predict the retention time very well both for a packed column and for a capillary column, in constant the velocity mode. 相似文献
250.
Cristian Simion Iwao Hashimoto Yoshiharu Mitoma Alina Marieta Simion Naoyoshi Egashira 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2480-2488
Various thioesters were obtained through an efficient phase-transfer catalysis method, by treating several thiophenols with different acyl chlorides, in a biphasic system composed of 10% aqueous NaOH and dichloromethane in the presence of tetrabutylammonium chloride. The thiolation reaction was complete in only 5 minutes, at 0°C. 相似文献