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91.
Poly(oxyethylene) (POE) was incorporated into the ionic clusters of ionomers, ethylene and methacrylic acid (7.2% neutralized with KOH) copolymer membrane. The changes of properties were studied from SAXS, DSC, IR and ionic conductivity. The IR study suggested that the coordinated structures in ionic clusters of the membrane were destroyed by POE incorporation, and also SAXS suggested that ionic clusters were swollen by POE incorporation. The ionic conductivity, a carrier being K+ in this system, increases from 10?16 S/cm to 10?9 S/cm at 30°C by the incorporation of POE (20.5 wt%). On the other hand, a large amount of POE (63 wt%) could be incorporated into ionomer membrane by the esterification of methacrylic acid groups (93%) with POE. When LiClO4 was added, ionic conduction occurred in the phase-separated POE domain, which had a low glass transition temperature (?55.2°C), showing an ionic conductivity 2.6 × 10?6 S/cm at 25°C. 相似文献
92.
We derive string-loop corrections (torus topology) to the quartic curvature term in the low-energy effective lagrangian for the heterotic string theory. The one-loop correction is found to give the relative weight of two tensor structures different from the tree level. 相似文献
93.
Effects of relaxation of occupied band electrons to the ?-hole state through the hybridization between ? and band states are studied based on a detailed model for Ce-monopnictides. The effective 4? level is shifted about 1–2 eV to shallow energy side from the unrenormalized bare level in processes in which the 4? electron is only virtually excited, such as in excitation to the vacant p band states through the p-? mixing. Photoemission spectra show two peaks, one near the Fermi energy and the other about 3 eV below it. The latter is shifted to deep energy side about 0.5–1 eV from the bare level when it lies near the bottom of the valence band. The discrepancy between the 4? level estimated from the low energy phenomena and that from photoemission is resolved. 相似文献
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95.
Katsuro Sakai 《Proceedings of the American Mathematical Society》1997,125(9):2809-2813
Let be the -dimensional universal Menger compactum, a -set in and a metrizable zero-dimensional compact group with the unit. It is proved that there exists a semi-free -action on such that is the fixed point set of every . As a corollary, it follows that each compactum with can be embedded in as the fixed point set of some semi-free -action on .
96.
Yoichi Sakai Satoru Onaka Masashi Takahashi Ryo Ogiso Tsutomu Takayama Tadahiro Nakamoto 《Hyperfine Interactions》2012,207(1-3):1-5
Magnetorheological (MR) fluids are new iron-based materials, whose applications include brakes, dampers, clutches, shock absorbers systems and polishing of optical surfaces (lens and mirrors). They are dependent on the size and shape of particles as the magnetic properties. Interested in the possibility of using iron-rich powders, commonly used in nondestructive testing, ranging in size from a few μm to about 200?μm and lower cost than those commercially used for MR fluids, a study of the structural and magnetic properties of iron-rich metallic particles by X-ray diffraction (XRD) and M?ssbauer spectroscopy (MS) at room temperature has been done. Powders, as received, were separated into particle sizes smaller than 20?μm (sample A) and in the range of 20–38?μm (sample B) because these are the sizes generally required for applications in MR fluids. The particles whose sizes exceed the above values were ground in a high energy planetary mill for 3?h, using different values of rotational speed/time: 200?rpm for one hour, a pause of 10?s, 140?rpm for one hour, pause 10?s and then 175?rpm during the last hour. These powders were sieved to obtain particles smaller than 20?μm (sample C). According XRD results, in all samples, only α-Fe (lattice parameter a = 2,867(2) ?) and Fe2O3 (lattice parameter a = 5,037(1) ? and c = 13,755(8) ?) were present. The M?ssbauer spectra were fitted with two sextets. The hyperfine parameters values allowed us to assign the highest relative area spectrum (sextet) corresponding to α-Fe and the second one to Fe2O3 in accord to the XRD results. Thus, the preparation method using mechanical milling for diminishing the size of the metallic particles allowed us to get particles with size and magnetic properties that could lead to potentially MR fluids applications. 相似文献
97.
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99.
Selective oxidation of an AlInAs layer was investigated for enhancement of magneto-optic effect in an optical isolator. Twelve times nonreciprocal phase shift enhancement was estimated from a measured AlInAs-oxide refractive index. 相似文献
100.
Jaffe DE Straub PB Adams MR Brown CN Charpak G Cooper WE Crittenden JA Finley DA Glass HD Gray R Hemmi Y Hsiung YB Hubbard JR Jonckheere AM Jöstlein H Kaplan DM Lederman LM Luk KB Maki A Mangeot P McCarthy RL Miyake K Plaag RE Rutherfoord JP Sakai Y Santiard JC Sauli F Smith SR Yoshida T Young KK 《Physical review D: Particles and fields》1989,40(9):2777-2795