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排序方式: 共有185条查询结果,搜索用时 31 毫秒
91.
Masahiro Murayama Noriyuki Sonoyama Atsuo Yamada Ryoji Kanno 《Solid State Ionics》2004,170(3-4):173-180
A new lithium ionic conductor of the thio-LISICON (LIthium SuperIonic CONductor) family was found in the binary Li2S–P2S5 system; the new solid solution with the composition range 0.0≤x≤0.27 in Li3+5xP1−xS4 was synthesized at 700 °C and characterized by X-ray diffraction measurements. Its electrical and electrochemical properties were studied by ac impedance and cyclic voltammetry measurements, respectively. The solid solution member at x=0.065 in Li3+5xP1−xS4 showed the highest conductivity value of 1.5×10−4 S cm−1 at 27 °C with negligible electronic conductivity and the activation energy of 22 kJ mol−1 which is characteristic of high ionic conduction state. The extra lithium ions in Li3PS4 created by partial substitution of P5+ for Li+ led to the large increase in ionic conductivity. In the solid solution range examined, the minimum conductivity was obtained for the compositions, Li3PS4 (x=0.0 in Li3+5xP1−xS4) and Li4P0.8S4 (x=0.2 in Li3+5xP1−xS4); this conductivity behavior is similar to other thio-LISICON family with the general formula, LixM1−yMy′S4 (M=Si, Ge, and M′=P, Al, Zn, Ga, Sb). Conduction mechanism and the material design concepts are discussed based on the conduction behavior and the structure considerations. 相似文献
92.
Takashi Moriyama Yoichi Takanishi Ken Ishikawa Hideo Takezoe Atsuo Fukuda 《Liquid crystals》1995,18(4):639-643
We have observed the diffusion constants of a dye in several liquid crystals by forced Rayleigh scattering. In a liquid crystal which has a standard phase sequence of N-SA-SC, the diffusion anisotropy changes at the N-SA phase transition and increases with decreasing temperature in SA and SC phases. The diffusion constants exhibit a rather smooth decrease with decreasing temperature except an anomaly at the SA-Sc phase transition. In a liquid crystal which has the antiferroelectric SCA phase, however, the diffusion constants show discontinuous increase and decrease at the SA-Sc and the Sc-ScA phase transition temperatures, respectively: the diffusion constant in SC is larger than that in the higher temperature SA phase. Anomalous signal increase and profile were observed at the phase transition temperatures, and were ascribed to the complementary transient grating due to the coexistence of two phases. 相似文献
93.
Different modes of cyclization in zoanthamine alkaloid system, bisaminal versus spiroketal formation
Nakajima T Yamashita D Suzuki K Nakazaki A Suzuki T Kobayashi S 《Organic letters》2011,13(12):2980-2983
Bisaminal cyclization in the zoanthamine alkaloid system was strongly affected by the stereochemistry of the C4 methyl. While cyclization of the (4S)-methyl precursor gave only a bisaminal compound, cyclization of the (4R)-methyl isomer produced both spiroketal and bisaminal products. 相似文献
94.
Chiral Schiff base complexes containing azo-groups, bis(N-R-1-naphtylethyl-4-phenyldiazenylsalicydenaminato) nickel(II), copper(II), and zinc(II) complexes affording a distorted square planar trans-[MN2O2] coordination geometry were prepared newly. Organic/inorganic hybrid materials in polymethylmethacrylate (PMMA) cast films of them (a containing type) or the analogous chiral Schiff base complexes, bis(N-R-1-phenylethyl-3,5-dichlorosalicydenaminato) nickel(II), copper(II), and zinc(II), and azobenzene (AZ) (a separated type) were assembled for comparison of polarized UV light induced molecular arrangement caused by Weigert effect. Investigation of parameters for optical anisotropy of metal complexes as well as AZ suggested that the degree of increasing optical anisotropy of the containing type is higher than that of the separated type based on π-π∗ (of which characteristic band appeared around 380 nm), n-π∗, and d-d bands of polarized absorption electronic spectra. Rigid nickel(II) or zinc(II) complexes are easy to increase optical anisotropy than flexible copper(II) complexes for both types. 相似文献
95.
For improving sound insulation of a double leaf dry partition, each leaf is often consisted of more than one panel. Previous study on predicting a transmission loss of double leaf partition, treats with the leaf varied just two kinds of panels and restricted to a leaf having same kind and same thickness. These restrictions are unfit for variety of current building materials and constructions. This study makes a prediction formula for a transmission loss of the double leaf partition with laminated leaves by a theoretical analysis and an experiment, and will discuss the predicted value with measured value in previous studies and catalogs. 相似文献
96.
Yumiko Takahashi Atsuo Iida Yoichi Takanishi Toyokazu Ogasawara Ken Ishikawa Hideo Takezoe 《Molecular Crystals and Liquid Crystals》2013,570(1):853-860
Abstract Direct observation of the local layer response of an antiferroelectric liquid crystal to the step form electric field has been carried out by a time resolved synchrotron X-ray micro diffraction measurement. When an electric field was changed from high voltage to OV, corresponding to the ferroelectric to antiferroelectric phase transition, the local layer transformed from the bookshelf to the quasi-bookshelf structure within 0.3 ms. The horizontal chevron structure was found in both the phases, though the decrease in the horizontal chevron angle was observed during a period of 0.2 ms after turning off the electric field. In the antiferroelectric to ferroelectric phase transition process (from OV to high voltage), the layer structure transformed to the bookshelf within 0.04 ms. 相似文献
97.
Takashi SAITO Daisuke MAKIURA Junichiro INOUE Hisayo DOI Kimikazu YAKUSHIJIN Atsuo OKAMURA Hiroshi MATSUOKA Toru MUKOHARA Ryuichi SAURA Yoshitada SAKAI Rei ONO 《Physical Therapy Research》2020,23(2):166
Objective: Chemotherapy-induced peripheral neuropathy (CIPN) is a common adverse event experienced by cancer patients. In general, CIPN is evaluated subjectively based on patient self-assessment or clinician-reported scales; evidence supporting the utility and validity of quantitative sensory tests (QST) is lacking in this patient population. The aim of this study was to objectively assess CIPN of lower extremities by QSTs, and to evaluate the concordance between QSTs and subjective assessments. Methods: In this prospective cohort study, outpatients with cancer receiving chemotherapy were recruited at a single university hospital. We assessed CIPN at the lower extremities at baseline and three months after baseline. The QSTs were performed by applying a monofilament and a tuning fork to determine touch and vibration thresholds, respectively, at the affected site. Subjective assessments were performed based on the visual analog scale (VAS) and the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE) toxicity grade. Kappa coefficients were calculated to evaluate the concordance between QSTs and subjective assessments. Results: After exclusion and drop-outs during follow-up, nineteen patients were included in the analysis. The prevalence of patients with abnormal sensation was 37% based on QSTs, 32% based on the VAS, and 14% based on CTCAE grading, respectively. Kappa coefficients were 0.32 between QSTs and VAS, and 0.28 between QSTs and CTCAE. Conclusions: The concordance rates between quantitative and subjective assessments were low. CIPN should be assessed using both quantitative and subjective assessments. 相似文献
98.
99.
Eu2+ doped A0.5Zr2(PO4)3 (A=Ca, Sr, Ba) phosphors with the NASICON structure were synthesized by a co-precipitation method. Their photoluminescent and structural properties were investigated by photoluminescent spectroscopy and powder X-ray Rietveld analysis, which determined two sites for Eu2+ ions in the host structure, 3a and 3b. The Eu-O bond lengths were increased by changing alkaline earth ions from Ca to Ba, causing Eu2+ emission bands to shift from blue-green to blue. A correlation was observed between the peak wavelength positions and the Eu-O bond length. The photoluminescent properties are discussed in terms of crystal field strength and nephelauxetic effect, and a schematic diagram of Eu2+ emissions is proposed for the Eu2+ doped NASICON phosphor. 相似文献
100.
We construct a q-boson representation of the Zamolodchikov-Faddeev algebra whose structure function is given by the stochastic R matrix of \(U_q(A^{(1)}_n)\) introduced recently. The representation involves quantum dilogarithm type infinite products in the \(n(n-1)/2\)-fold tensor product of q-bosons. It leads to a matrix product formula of the stationary probabilities in the \(U_q(A_n^{(1)})\)-zero range process on a one-dimensional periodic lattice. 相似文献