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121.
Journal of High Energy Physics - This paper shows that the positive-energy and non-renormalization theorems of traditional supersymmetry survive the addition of Lorentz violating interactions. The... 相似文献
122.
Takaaki Sakai Seok-Jun Kim Satoshi Kajitani Jun-ichi Hamagami Hiroyuki Oda Maki Matsuka Tatsumi Ishihara Hiroshige Matsumoto 《Journal of Solid State Electrochemistry》2012,16(6):2055-2059
The proton conduction properties of sulfuric acid-modified nano-titania prepared by impregnation method were investigated. The proton conductivity of sulfuric acid-modified nano-titania was almost the same as that of hydrous sulfated nano-titania investigated in our previous work when the amount of adsorbed sulfate groups was almost the same. The highest conductivity was obtained at an adsorbed sulfate group amount of 0.42?mmol/g, not 0.97?mmol/g. This result indicates that the enhancement of conductivity with increasing amount of adsorbed sulfate groups is limited. This might be attributable to insufficient water molecule adsorption on the Ti4+ site coordinated with a bidentate sulfate group due to the prevention by excess sulfuric acid. 相似文献
123.
Sequential sigmatropic rearrangements (Claisen/Claisen and Claisen/Overman) of enantiopure allylic diols are described. The reactions proceeded in complete diastereoselectivity without protecting group manipulations. The sequential Claisen/Overman rearrangement was successfully applied to the total synthesis of (-)-kainic acid. 相似文献
124.
Tomohiko Nakajima Tetsuo Tsuchiya Takaaki Manabe 《Applied Physics A: Materials Science & Processing》2010,98(4):885-888
Ternary oxide Zn3V2O8 films was successfully formed on glass substrates only by means of vacuum ultraviolet irradiation to the spin-coated metal–organic
solutions. From Fourier transform infrared spectroscopy measurements, we confirmed that the crystal growth proceeded at metal–organic
bond cleavage under VUV irradiation. The crystalline size of the obtained materials was estimated to be 1.5–2.5 nm. The prepared
Zn3V2O8 films clearly showed yellow luminescence, corresponding to a charge transfer transition in the VO4 tetrahedra. 相似文献
125.
126.
Takaaki Shimura 《Extremes》2012,15(3):299-317
In this paper we discuss the discretization of distributions belonging to some max-domain of attraction. Given a random variable X its discretization is defined as the minimal integer not less than X. Our first interest is on distributions that preserve the max-domain property after discretization. Secondly, we characterize the distributions which are regarded as the discretization of the distribution in the Gumbel max-domain of attraction. Lastly the correspondence of distribution in Gumbel max-domain of attraction is investigated. 相似文献
127.
Duncan M. A. Grieve Graham E. Lewis Michael D. Ravenscroft Peter Skrabal Takaaki Sonoda Ivanka Szele Heinrich Zollinger 《Helvetica chimica acta》1985,68(5):1427-1443
The thermal N2 exchange of a number of 15N-labelled diazo compounds was studied in solution. The compounds involved were 3-diazo-1-methylindolin-2-one ( 1 ), 9-diazofluorene ( 2 ), 5-diazo-1,3-cyclopentadiene-1,2,3,4-tetracarbonitrile ( 3 ), 2-diazo-2H-imidazole-4,5-dicarbonitrile ( 4 ), 4-diazocyclohexa-2,5-dienone ( 5 ), and the conjugate acids of 4 and 5 , namely 4,5-dicyano-1H-imidazole-2-diazonium ion ( 6 ) and 4-hydroxybenzenediazonium ion ( 7 ). Only 1 , 4 , 6 , and 7 exchange their diazo group with ‘external’ molecular N2. The results are explained on the hypothesis that only organic species which have an empty σ orbital and which are effective in π electron back-donation are able to react with N2. Thus, reaction with carbenes is likely to occur only if the carbene is in the 1A2 singlet state and if its electrophilicity is high. 相似文献
128.
Kakiyama G Hosoda A Iida T Fujimoto Y Goto T Mano N Goto J Nambara T 《Journal of chromatography. A》2006,1125(1):112-116
A direct method for the separation and quantification of a series of bile acid acyl glycosides using high-performance liquid chromatography coupled to an evaporative light scattering detector (HPLC-ELSD) is described. Complete separation of each of 15 bile acid acyl 24-alpha-glucosides and their 24-beta-anomers and 24-beta-galactosides was achieved by the stepwise gradient elution mode on a C18 column using a mixture of acetonitrile-methanol (8:2, v/v) and 1% aqueous acetic acid as the mobile phase. 24-beta-Galactosides were always eluted faster than the corresponding 24-beta-glucosides, which eluted after the corresponding 24-alpha-anomers. Calibration curves of different 24-beta-galactosides were linear over a range of 0.2-40 nmol of injected amount and the detection limits (S/N > 3) were from 0.08 to 0.1 nmol. The present HPLC-ELSD method may provide an insight into the separation and quantification of the biologically interesting neutral bile acids. 相似文献
129.
Akamatsu K Fukumoto Y Taniyama T Tsuruoka T Yanagimoto H Nawafune H 《Langmuir : the ACS journal of surfaces and colloids》2011,27(19):11761-11766
We report a fully additive-based electrochemical approach to the site-selective deposition of silver on a polyimide substrate. Using a cathode coated with ion-doped precursor polyimide layers, patterns of metal masks used as anodes were successfully reproduced at the cathode-precursor interface through electrochemical and ion-exchange reactions, which resulted in the generation of silver patterns on the polyimide films after subsequent annealing and removal from the substrate. Excellent interfacial adhesion was achieved through metal nanostructures consisting of interconnecting silver nanoparticles at the metal-polymer interface, which are electrochemically grown "in" the precursor layer. This approach is a resist- and etch-free process and thus provides an effective methodology toward lower-cost and high-throughput microfabrication. 相似文献
130.
Takahashi Y Kubota T Shibazaki A Gonoi T Fromont J Kobayashi J 《Organic letters》2011,13(12):3016-3019
Three new heteroaromatic alkaloids, nakijinamines C-E (1-3), which are a hybrid of the aaptamine-type and bromoindole alkaloids possessing a taurine- or histidine-derived residue, have been isolated from an Okinawan marine sponge Suberites species. The structures of 1-3 were elucidated on the basis of spectroscopic data and chemical conversions. Nakijinamines C (1) and E (3) are the first natural products possessing a 1H-oxazolo[4',5':4,5]benzo[1,2,3-de][1,6]naphthyridine ring system. 相似文献