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1.
2.
Yasuyuki Agari Kiyofumi Sakai Yosikazu Kano Ryoki Nomura 《Journal of Polymer Science.Polymer Physics》2007,45(21):2972-2981
We prepared biodegradable poly(ethylene oxide) (PEO)/poly(L ‐lactic acid) (PLLA) graded blends by the dissolution–diffusion process, and discussed the biodegradability and tensile strength of the graded blends by comparing isotropic blend and PLLA only. All the graded blends were degraded more largely than the PLLA only and isotropic blend (PEO: 37.5 wt %), which had the same content as the total content of those graded blends. The graded blend having most excellent wide compositional gradient was degraded most largely with the enzyme. Thus, graded structure of the blends promoted their biodegradabilities large. It was considered that the dissolution of PEO with water increased the surface area attacked by the enzyme, while PEO caught PLLA oligomers to promote the biodegradation of PLLA. Then, the biodegradabilities of the graded blends were suppressed by the increasing crystallinity of PLLA. Furthermore, the strengths of all the graded blends were larger than those of the isotropic blend. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2972–2981, 2007 相似文献
3.
Let Cld
AW
(X) be the hyperspace of nonempty closed subsets of a normed linear space X with the Attouch–Wets topology. It is shown that the space Cld
AW
(X) and its various subspaces are AR's. Moreover, if X is an infinite-dimensional Banach space with weight w(X) then Cld
AW
(X) is homeomorphic to a Hilbert space with weight 2
w(X). 相似文献
4.
5.
To find an effective extraction and removal method for palladium(II), which is one of the main fission products from an acidic nuclear spent fuel solution, the extraction behavior of palladium(II) from a nitric acid medium by an acidic chelating extractant, 1-phenyl-3-methyl-4-trifluoroacetylpyrazolone-5-one (HPMTP) and a tertiary amine of high molecular weight, tri-n-octylamine (TOA), has been studied by spectrophotometry. A noticeable antagonistic extraction effect was observed in the extraction system under the given conditions. To understand this phenomenon, a preliminary investigation was performed to explain the mechanism of this reaction. According to the theory of corresponding solutions (TCS), the association reaction between HPMTP and TOA is proposed in the organic phase. An associated species, HPMTP·TOA, formed through hydrogen bonding in a chloroform medium might be the main reason why an antagonistic extraction effect occurred. The association constant between HPMTP and TOA was calculated to be 2.86±0.05. 相似文献
6.
The propagation characteristics of shear horizontally polarized (SH) waves passing through (Ni42Nb28Zr30)100–x Hx (x = 0–15.2) glassy alloys were investigated as a function of hydrogen content. With an increase in hydrogen content, the propagation time and main frequency of the receiving waves show increase and decrease, respectively, indicating expan‐ sion in average atomic distance which comes from solution of hydrogen. In sharp contrast to crystalline alloys, the decrease in damping ratio and the delay in phase with increasing hydrogen suggest a strong settlement of hydrogen into four‐coordination sites surrounded tetrahedrally by four Zr atoms and the resulting increase in dynamic elasticity, respectively. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
7.
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
8.
Teruhisa Horita Katsuhiko Yamaji Natsuko Sakai Yueping Xiong Harumi Yokokawa Tatsuya Kawada 《Ionics》2002,8(1-2):108-117
The oxygen reduction active sites were visualized around the O2/SOFC cathode/electrolyte triple phase boundaries (TPB) by the16O/18O exchange techniques and secondary ion mass spectrometry (SIMS) analysis. The higher18O concentration is observed on the cathode top surfaces (La0.9Sr0.1MnO3-mesh, Au-mesh, and Ag-porous), which suggested the promotion of oxygen adsorption and oxygen surface exchange at the cathode.
The oxygen diffusion through the bulk of cathode occurred at the La0.9Sr0.1MnO3-mesh and the Ag-porous cathodes, not at the Au-mesh cathode. On the YSZ surfaces after removing the cathode, the active sites
for oxygen incorporation were analyzed by SIMS. The active sites for oxygen incorporation were at the La0.9Sr0.1MnO3/YSZ interface as well as the TPB. On the other hand, the active sites for oxygen incorporation are limited to the TPB in
the case of the Au-mesh removed YSZ surface. From the SIMS analysis, the expansion of the active sites for oxygen incorporation
is less than a few μm from the TPB lines.
Paper presented at the 8th EuroConference on Ionics, Carvoeiro, Algarve, Portugal, Sept. 16–22, 2001. 相似文献
9.
10.
P. Periasamy K. Tatsumi N. Kalaiselvi M. Shikano T. Fiyieda Y. Saito T. Sakai M. Mizukata A. Kajinami S. Deki 《Ionics》2002,8(5-6):453-460
A series of gel polymer electrolytes containing PVdF as homo polymer, a mixture of 1:1 Ethylene Carbonate (EC) : Propylene
Carbonate (PC) as plasticizer and lithium-bistrifluoromethane sulphone imide [imide — LiN (CF3SO2)2] has been developed. Amounts of polymer (PVdF), plasticizer and the imide lithium salt have been varied as a function of
their weight ratio composition in this regard. Dimensionally stable films possessing appreciable room temperature conductivity
values have been obtained with respect to certain weight ratio compositions. However, conductivity data have been recorded
at different possible temperatures, i.e., from 20 °C to 65 °C. XRD and DSC studies were carried out to characterize the polymer
films for better amorphicity and reduced glass transition temperature, respectively. The electrochemical interface stability
of the PVdF based gel polymer electrolytes over a range of storage period (24 h – 10 days) have been investigated using A.C.
impedance studies. Test cells containing Li/gel polymer electrolyte (GPE)/Li have been subjected to undergo 50 charge-discharge
cycles in order to understand the electrochemical performance behaviour of the dimensionally stable films of superior conductivity.
The observed capacity fade of less than 20% even after 50 cycles is in favour of the electrochemical stability of the gel
polymer electrolyte containing 27.5% PVdF −67.5 % EC+PC −5% imide salt. Cyclic voltammetry studies establish the possibility
of a reversible intercalation — deintercalation process involving Li+ ions through the gel polymer electrolyte. 相似文献