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111.
Gas permeability of thin dense films from polymer blend of thermoplastic elastomer and polyolefin 下载免费PDF全文
Masamoto Uenishi Noriaki Fukushima Masashi Teramachi Masahiko Mizuta Jun Kamo Toshinori Tsuru 《应用聚合物科学杂志》2014,131(1)
Stretched thin films composed of a thermoplastic elastomer, a polystyrene‐block‐poly(ethylene butylene)‐block‐polystyrene triblock copolymer (SEBS), and polyolefins, poly(ethylene‐co‐ethylacrylate) and poly(ethylene‐co‐propylene), were obtained by blow‐molding, uniaxial stretching, and cooling to room temperature and the gas permeability of the stretched films was investigated. When the as‐blown annealed film was subjected to uniaxial stretching in the machine direction, PO2 and PN2 increased with an increase in the stretching ratio K and approached a constant value at high stretching ratios. In addition, PO2/PN2 decreased gradually with K and approached a value of 2.95–3.0. The reason for this unique gas permeation behavior is that the molecular mobility of poly(ethylene butylene) chains in a direction normal to the film increases and reaches an equilibrium state at around K = 4.5. The change in gas permeability of the stretched films can be explained using a deformation model for the SEBS matrix. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39386. 相似文献
112.
Different sizes of zeolite nanocrystals were fabricated from zeolite microparticles using a centrifugation-assisted grinding method. The zeolite nanocrystal formation can be attributed to the Al2O3 bowl mill generation of mechanical stress that fractured zeolite microparticles into smaller fragments. In the present study, the smaller fragments had a wide distribution of size and morphology. Therefore, different sizes of zeolite nanocrystals could be recovered from these smaller fragments by varying the centrifugation process. Zeolite nanocrystal product yields were measured by periodically recovering the nanocrystals from the smaller fragments based on milled zeolite powder. The larger crystals of zeolite were typically irregular in shape, whereas the smaller zeolite nanocrystals tended to be spherical. High product yield of the zeolite nanocrystals was obtained by periodically removing nanocrystals from the milled zeolite powder and recycling the large zeolite particles. Thus, the results from this new hybrid process suggest that it can be used to fabricate differing sizes of zeolite nanocrystals. In addition, the size of the recovered zeolite nanocrystal products was narrow, and the initial zeolite nanocrystal structure was not destroyed by the mechanical stress. 相似文献
113.
The Na+-fast ionic conducting glass-ceramics with Na5YSi4O12 (N5)-type structure were successfully synthesized using the composition formula of Na3+3x-y
R1-x
P
y
Si3-y
O9 for a variety of rare earth ions, R, under the appropriate composition parameters. In the crystallization of N5-type glass-ceramics, its relatives (Na3YSi3O9 (N3)- and Na9YSi6O18 (N9)-type glass-ceramics) structurally belonging to the family of Na24−3x
Y
x
Si12O36 were found to crystallize as the precursor phase at low temperatures. In order to produce N5 single phase glass-ceramics,
the concentration of both phosphorus and rare earth was found important. The meaning of the composition was evaluated by thermodynamic
and kinetic studies on the phase transformation of metastable N3 or N9 phases to stable N5 phase with Na+-fast ionic conductivity. The possible combinations of x and y became more limited for the crystallization of the fast ionic conducting phase as the ionic radius of R increased, while the Na+ conduction properties were more enhanced in the glass-ceramics of larger R. These results are discussed in view of the structure and the conduction mechanism. Also studied were the microstructural
effects on the conduction properties, which were dependent upon the heating conditions of crystallization. These effects were
understood in relation to the grain boundary conduction properties as well as the transmission electron microstructural morphology
of grain boundaries. 相似文献
114.
Vu Thi Huong Toshinori Shimanouchi Do Phuc Quan Hiroshi Umakoshi Pham Hung Viet Ryoichi Kuboi 《Journal of Applied Electrochemistry》2009,39(10):2035-2042
The possible use of an electrode modified with electroactive conductive poly(3-methylthiophene) (PMeT)/Nafion as a chemical
sensor was investigated for the voltammetric analysis of Dopamine (DA). The electrochemical behavior of dopamine was examined
by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques. By using a PMeT-modified glassy carbon (GC/PMeT)
electrode, DA and Ascorbic Acid (AA) signals could be separated but the AA at high concentrations still caused significant
interference by overlapping the DA peak. In comparison to the GC/PMeT electrode, the glassy carbon (GC/Nafion/PMeT) electrode
modified with hybrid film Nafion/PMeT was found to permit a superior separation by shifting the oxidation of AA peak toward
the less positive potential. The DPV curves for a mixture of DA and AA at an GC/Nafion/PMeT electrode in a 0.1 M H2SO4 solution showed peaks of DA and AA, at 0.45 and 0.21 V, respectively, indicating that the difference in the oxidation potential
was 240 mV. In the 0.1 M H2SO4 solution, the oxidation peak current on the differential pulse voltammograms for the GC/PMeT electrode increased linearly
with the concentration of DA in the range 1 × 10−6 to 1 × 10−3 M, and the oxidation peak current on the differential pulse voltammograms for the GC/Nafion/PMeT electrode in the range 5 × 10−7 to 2 × 10−4 M. The DA detection sensitivity of the GC/Nafion/PMeT electrode (26.7 μA μM−1 cm−2) was 22 times higher than that of the GC/PMeT electrode (1.21 μA μM−1 cm−2). 相似文献
115.
Gang Li Masakoto KanezashiHye Ryeon Lee Makoto MaedaTomohisa Yoshioka Toshinori Tsuru 《International Journal of Hydrogen Energy》2012
A novel bimodal catalytic membrane reactor (BCMR) consisting of a Ru/γ-Al2O3/α-Al2O3 bimodal catalytic support and a silica separation layer was proposed. The catalytic activity of the support was successfully improved due to enhanced Ru dispersion by the increased specific surface area for the γ-Al2O3/α-Al2O3 bimodal structure. The silica separation layer was prepared via a sol–gel process, showing a H2 permeance of 2.6 × 10−7 mol Pa−1 m−2 s−1, with H2/NH3 and H2/N2 permeance ratios of 120 and 180 at 500 °C. The BCMR was applied to NH3 decomposition for COx-free hydrogen production. When the reaction was carried out with a NH3 feed flow rate of 40 ml min−1 at 450 °C and the reaction pressure was increased from 0.1 to 0.3 MPa, NH3 conversion decreased from 50.8 to 35.5% without H2 extraction mainly due to the increased H2 inhibition effect. With H2 extraction, however, NH3 conversion increased from 68.8 to 74.4% due to the enhanced driving force for H2 permeation through the membrane. 相似文献
116.
117.
Hirose Hideo Hikita Masayuki Ohtsuka Shinya Tsuru Shin-ichirou Ichimaru Junji 《Dielectrics and Electrical Insulation, IEEE Transactions on》2008,15(5):1252-1260
To diagnose the electric power apparatus, the decision tree method can be a highly recommended classification tool because it provides the if-then-rule in visible, and thus we may have a possibility to connect the physical phenomena to the observed signals. The most important point in constructing the diagnosing system is to make clear the relations between the faults and the corresponding signals. Such a database system can be built up in the laboratory using a model electric power apparatus, and we have made it. The next important thing is the feature extraction. We used ø - V - n patterns and POW patterns for feature variables, and feature extraction is made by the extended moments, usual moments, and the parameters in the underlying distributions such as the generalized normal distribution and the Weibull distribution. By simple arrangements, we will be able to classify the faults and noise with high accuracy such that the misclassification rate is lower than 5%. If we set appropriate pre-processing procedure carefully, we might have a possibility of classification accuracy of less than 2%. Therefore, the decision tree with adequate feature extraction is considered to be a promising method as one of the classification tools 相似文献
118.
Mitsuhiro Fukuta Tadashi Yanagisawa Toshinori Arai Yasuhiro Ogi 《International Journal of Refrigeration》2003,26(7):823-829
A capillary tube is widely used as an expansion device for small refrigeration cycles. In a practical refrigeration cycle, some amount of refrigeration oil is discharged from a compressor and refrigerant/oil mixture flows through the capillary tube. This study investigated experimentally the influence of mixing of the refrigeration oil with the refrigerant on the flow through the capillary tube. The experiments are carried out with not only a miscible combination of refrigerant and oil but also an immiscible combination. In both cases, the mass flow rate through the capillary tube and temperature and pressure distributions along the tube are measured under several conditions of subcooled degree and oil concentration. In the case of miscible combination, the mass flow rate of refrigerant decreases with increasing the oil concentration because the viscosity of liquid phase increases by the mixing of viscous oil. Even in the case of the immiscible combination, the oil droplet is so small that it mixes homogeneously in the liquid phase in the capillary tube and the refrigerant mass flow rate decreases by the mixing of immiscible oil. There is no significant influence of the oil concentration on the underpressure, which means pressure difference between saturation pressure and flash inception pressure, in both miscible and immiscible combinations. 相似文献
119.
120.
The present paper introduces a new data analyzer, a compression-based self-organizing recognizer, the PRDC-CSOR (Pattern Representation scheme using Data Compression – Compression based Self ORganizing Recognizer), with a preliminary application to image data. The PRDC-CSOR is an extension of the authors’ previously proposed pattern representation scheme using data compression (PRDC). Contrary to the traditional statistical-model-based recognition system methods, the PRDC-CSOR constructs itself using incoming data only. The basic tool, compressibility, is an approximation of the Kolmogorov complexity K(x) defined in an individual text x as a countermeasure against the Shannon entropy H(X) defined on an ensemble X. Due to this feature, a highly automatic self-organizing recognition system becomes possible as demonstrated in this paper. 相似文献