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Shinji Ejiri Sinya Aoki Tetsuo Hatsuda Kazuyuki Kanaya Yoshiyuki Nakagawa Hiroshi Ohno Hana Saito Takashi Umeda 《Central European Journal of Physics》2012,10(6):1322-1325
We study the QCD phase structure at high temperature and density adopting a histogram method. Because the quark determinant is complex at finite density, the Monte-Carlo method cannot be applied directly. We use a reweighting method and try to solve the problems which arise in the reweighting method, i.e. the sign problem and the overlap problem. We discuss the chemical potential dependence of the probability distribution function in the heavy quark mass region and examine the applicability of the approach in the light quark region. 相似文献
43.
Birendra Babu Adhikari Cuong-Alexander To Tetsuo Iwasawa 《Supramolecular chemistry》2013,25(10):724-730
Calix[6]arene hexacarboxylic acid binds instantly and with low symmetry to Pb, Sr and Ba. Later a highly symmetric up-down alternating conformation emerges. The solution structures are identical to their p-tert-butylcalix[6]arene hexacarboxylic acid counterparts. With either receptor, an octahedral cage is formed around the metal. The transformation from low to high symmetry however proceeds at significantly faster rates for the de-t-butylated host. 相似文献
44.
Yoshio Aso Shoji Nishiguchi Tetsuya Jigami Tetsuo Otsubo Fumio Ogura 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):417-418
Several well-defined 3,4-thienylene-ethynylene oligomers with different chain lengths have been synthesized and characterized. X-Ray crystallographic analyses proved their unique, totally helical conformations. 相似文献
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Takahiro Egawa Kazuhisa Hirabayashi Dr. Yuichiro Koide Chiaki Kobayashi Dr. Naoya Takahashi Dr. Tomoko Mineno Dr. Takuya Terai Dr. Tasuku Ueno Dr. Toru Komatsu Dr. Yuji Ikegaya Prof. Norio Matsuki Prof. Tetsuo Nagano Dr. Kenjiro Hanaoka 《Angewandte Chemie (International ed. in English)》2013,52(14):3874-3877
48.
The formation of carbon-carbon bond by sulfur extrusion such as pyrolysis of cyclic sulfones is well known as an important synthetic method, especially for the synthesis of cyclophane framework.1) Little is known about selenium extrusion as the counterpart, though organoseleniums have been properly appreciated as a useful tool for manipulating a functional group.2) Lardon reported that the thermal decomposition of dibenzyl diselenide led to a mixture of dibenzyl selenide and polyselenides.3) In contrast, recent reports showed that at 210°C, heating bis(diphenylmethyl) diselenide resulted in ready selenium extrusion to 1,1,2,2-tetraphenylethane4), and dianthrylmethyl mono- and diselenides to 1,2-dianthrylethane.5) Therefore,- it is worthwhile to study the thermal behavior of dibenzyl selenide itself. 相似文献
49.
Chiral γ-lactones of both enantiomers were synthesized with more than 90% optical purities. The key step was Novozym 435–catalyzed hydrolysis of racemic N-benzyl-4-acetoxyalkylamides. Additionally, because (R)-γ-lactones are predominant in apricot, mango, peach, passion fruit, and strawberry, synthesis was attempted using only one enantiomer selectively. The (R)-enantimer was synthesized with more than 80% total yield and more than 90% optical purity by a combination of Novozym 435–catalyzed hydrolysis and the Mitsunobu reaction. 相似文献
50.
Tetsuo Sakamoto Kenji Ohishi Shun‐ichi Hayashi Masaaki Fujii 《Surface and interface analysis : SIA》2013,45(8):1309-1312
Aiming for the highly sensitive analysis of aromatic hydrocarbons in organic mixtures, selective ionization using an ultraviolet laser ionization technique was examined for the determination of sputtered neutral species on organic surfaces. The mass spectrum of a model mixture containing pyrene and n‐alkane showed that only pyrene was ionized and detected, whereas a mass spectrum without laser irradiation, i.e. in the case of secondary ion mass spectrometry, was dominated by many n‐alkane fragment peaks. This technique was applied for the detection of polyaromatic hydrocarbons adsorbed on diesel exhaust particles. Two kinds of polyaromatic hydrocarbons were clearly detected because many aliphatic fragment signals were suppressed by means of ultraviolet laser ionization. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献