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1.
Natural-abundance 17O NMR spectra have been measured for twenty one oxiranes. Their chemical shifts covering a 100 ppm range were interpreted in terms of the paramagnetic β- and diamagnetic γ-effects. In addition, through-space orbital interaction between the ethylenic π and the Walsh orbitals of the oxirane ring was suggested by a lowfield shift in norbornadiene exo-oxide.  相似文献   
2.
Cubic antimonic acid (Sb2O5·nH2O) films were successfully prepared on stainless steel and Si(100) substrates by electrophoretic deposition (EPD) using two types of sols. The sols were prepared by reacting an H2O2 aqueous solution with Sb(O-i-C3H7)3 or metallic Sb powder. The resulting films were found to consist of fine particles of cubic Sb2O5·nH2O single crystals with uniform particle sizes of 30 nm and 150 nm. The weight of the Sb2O5·nH2O deposit on the anode Si(100) substrate by EPD increased linearly with the current density in the range of 0–0.67 mA cm–2, when the sol pH was over 7. The proton conductivity of the polycrystalline Sb2O5·nH2O discs, formed from the two types of sols, was evaluated by an ac impedance method at room temperature under controlled levels of relative humidity.  相似文献   
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Beam polarization asymmetries for the p(gamma-->,K+)Lambda and p(gamma-->,K+)Sigma(0) reactions are measured for the first time for E(gamma)=1.5-2.4 GeV and 0.6相似文献   
5.
We developed a novel fluorescence labeling technique for quantification of surface densities of atom transfer radical polymerization (ATRP) initiators on polymer particles. The cationic P(St‐CPEM‐C4DMAEMA) and anionic P(St‐CPEM) polymer latex particles carrying ATRP‐initiating chlorine groups were prepared by emulsifier‐free emulsion polymerization of styrene (St), 2‐(2‐chloropropionyloxy)ethyl methacrylate (CPEM), and N‐n‐butyl‐N,N‐dimethyl‐N‐(2‐methacryloyloxy)ethylammonium bromide (C4DMAEMA). ATRP initiators on the surface of polymer particles were converted into azide groups by sodium azide, followed by fluorescent labeling with 5‐(N,N‐dimethylamino)‐N′‐(prop‐2‐yn‐1‐yl)naphthalene‐1‐sulfonamide (Dansyl‐alkyne) by copper‐catalyzed azide‐alkyne cycloaddition (CuAAC). The reaction time required for both azidation of ATRP‐initiating groups and successive fluorescence labeling of azide groups with Dansyl‐alkyne by CuAAC were investigated in detail by FTIR and fluorescence spectral measurement, respectively. The ATRP initiator densities on the cationic P(St‐CPEM‐C4DMAEMA) and anionic P(St‐CPEM) particle surfaces were estimated to be 0.21 and 0.15 molecules nm?2, respectively, which gave close agreement with values previously determined by a conductometric titration method. The fluorescence labeling through click chemistry proposed herein is a versatile technique to quantify the surface ATRP initiator density both on anionic and cationic polymer particles. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 4042–4051  相似文献   
6.
Blue phases (BPs) obtained by doping a commercially available liquid crystalline compound (4-butyl-N-(4-ethoxybenzylidene)aniline (EBBA)) with (2R,3R)-2,3-bis(4-octyloxyphenylbenzoyloxy)-N-(hydroxydecyl)succinimide (1) were highly stabilised by the addition of a small amount of alkane diols. Especially, addition of only 0.5 mol% of octane-1,8-diol increased the BPIso transition temperature by 10 K and widened the BP temperature range up to 35 K. A model stabilisation mechanism based on the construction of a hydrogen bond network in each disclination zone in BPs was proposed.  相似文献   
7.
We are carrying out hadron photoproduction experiments by using polarized photon beams at SPring-8 in Japan.In 2005,we started developing a polarized HD target for future experiments using both the polarized photon beams and the polarized target.The polarized HD target is an idealistic target for experiments observing reactions with small cross sections because the HD does not include heavy nuclei which produce many background events.The measurement of double polarization asymmetries is expected to give much important information to investigate the nucleon hidden structure,hadron photoproduction dynamics,and exotic hadron property.We report on the present status of the development of the polarized HD target al RCNP.  相似文献   
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Muneyuki Tsuda 《Surface science》2006,600(18):3992-3994
We investigate O2 binding to cytochrome c oxidase (CcO)-inspired nanomaterials using ab initio density functional calculations. We consider iron-porphyrin (FeP) and copper-(imidazole)3 [Cu(Im)3] as a representative of the active binuclear center, and explore the effect of the Cu(Im)3 on the FeP-O2 adduct in relation to the geometric, vibrational, electronic and energetic properties. We find that the Cu(Im)3 induces the weak O-O and Fe-O bonds mainly because of the electron transfer to the O2 and the spin polarization of the Fe and O2 by bridging the O2 between the Fe and Cu, possibly resulting in the facile O2 dissociation.  相似文献   
10.
Irradiation of graphite fluoride with electron beams has been carried out on a electron probe microanalyzer. Radiation-induced decomposition took place predominantly instead of thermal decomposition. The decomposition tended to occur in the following order: powdery (CF)n, white flaky (CF)n, and (CF2F)n. The kinetics of the decomposition reaction induced by electron beams was evaluated by the ZAF correction of the measured intensities of F K- and C K-emission bands. It was found that the kinetic of the decomposition of graphite fluoride was of Avrami-Erofejev type; the rate equations were -ln(1?α)=kt12 for (CF)n and -ln(1?α)=kt2 for (C2F)n. An application to the electron microbeam processing of graphite fluoride was suggested in relation to its unique physicochemical properties.  相似文献   
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