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101.
We have observed periodically aligned nanovoid structures inside a conventional borosilicate glass induced by a single femtosecond (fs) laser beam for the first time, to our knowledge. The spherical voids of nanosized diameter were aligned spontaneously with a period along the propagation direction of the laser beam. The period, the number of voids, and the whole length of the aligned void structure were controlled by changing the laser power, the pulse number, and the position of the focal point. 相似文献
102.
103.
Tiger stripe of injection molding of polypropylene (PP)/elastomer/talc blends was analyzed in terms of the morphology of the dispersed phase comprising elastomer components by using gloss and scanning electron microscopy (SEM). In addition, the contribution of the polymer design of PP, i.e., industrial block‐type grade consisting of a homo‐PP portion as the matrix and an ethylene propylene random copolymer portion as the domain is discussed. Local gloss measurement of the injected specimen along with the flow direction of the molten blends indicates a periodic fluctuation repeating higher and lower degrees of gloss, corresponding to the period of glossy and cloudy portions of the tiger stripe, respectively. These local gloss degrees are highly dependent on the morphologies of the dispersed phases near the surface layer of the injected specimen. The gloss increases when the ratio long axis (L) and diameter (D), L/D, of the dispersed phase are increased, and the gloss decreases when the L/D is decreased. Increasing the intrinsic viscosity of the ethylene‐propylene rubber portion of the PP is an effective design factor for restricting the deformation against shear strain during injection process by giving the dispersed phases high elasticity. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 192–199, 2007 相似文献
104.
Hiroshi Watanabe Koki Nishizawa Osamu Takaki 《Electronic Notes in Theoretical Computer Science》2006,164(1):177-194
The Cone of Influence Reduction is a fundamental abstraction technique for reducing the size of models used in symbolic model checking. We develop coalgebraic representations of systems as composites of state transition maps and connectors. These representations include synchronous systems, asynchronous systems, asynchronous systems with synchronization by channels, and those with shared variables, probabilistic synchronous systems and so on. We schematically show the cone of influence reduction using these coalgebraic representations, which give a unified framework for providing the technique for various kinds of systems. 相似文献
105.
Nanoparticles (NPs) elicit various physiological responses in cellular environment, and the effect of NPs on cell migration is of high interest. In this work, the effects of NPs on cell migration and their possible mechanisms were studied. Here, we showed that after exposure to pegylated titanium dioxide nanoparticles (TiO2-PEG NPs, where PEG stands for the polyethylene glycol), NCI-H292 cells exhibited slower migration than control cells. Furthermore, larger NPs inhibited cell migration much stronger than smaller NPs. Following NP exposure, the cells showed decreased expression of integrin beta 1 and phosphorylated focal adhesion kinase (pFAK), and disrupted F-actin structures. We demonstrated that a possible mechanism involved NP-mediated promotion of the lysosomal degradation of integrin beta 1, thus leading to reduced expression of pFAK and cytoskeletal disruption and inhibited cell migration. Therefore, our results showed that inhibition of NCI-H292 cell migration by NPs is mediated through integrin beta 1, which provides useful information for the application of NPs in cancer therapy and related fields. 相似文献
106.
Koki Tazoe Shigeru Hamada Hiroshi Noguchi 《International Journal of Hydrogen Energy》2017,42(18):13158-13170
In this study, stress intensity factor range (ΔK) decreasing tests were conducted and the in-situ observations were used to investigate the fatigue crack growth behavior of JIS SCM440 steel near the fatigue threshold in a 9-MPa hydrogen gas environment. The fatigue crack growth rate reflected the threshold behavior of the material, although the crack propagation knee point immediately before the threshold stress intensity factor range (ΔKth) could not be distinctly identified. The fatigue crack was also observed to exhibit uneven propagation immediately before ΔKth. In contrast, the knee points in a helium gas environment and air were very distinct. Fractographic analysis further revealed the existence of intergranular facets, which were observed immediately before ΔKth in the hydrogen gas environment. Conversely, no facet was observed immediately before ΔKth in the helium gas environment and air. The formation of the facets was considered to be one of the causes of the uneven crack propagation immediately before ΔKth in the hydrogen gas environment. 相似文献
107.
Hatayama R Chiba K Noda K Takahashi R Kanehira T Serata K Shinohara M Tokuyama T 《Journal of Bioscience and Bioengineering》1999,87(2):245-248
A high-concentration-ammonium sulfate-requiring, ammonia-oxidizing bacterium, strain K1, was newly isolated from packed tower biological deodorization plants of chicken farms. The cells of strain K1 are rods (0.1-1.0 x 1.0-2.0 microm), gram negative, obligately aerobic, and nonmotile. Colonies (1-2 mm in diameter) on a plate culture are reddish, circular, and smooth. Intracytoplasmic membranes characteristic of nitrifying bacteria are present. The G+C content of the total DNA is 48.5 mol%. The similarity of 16S rRNA (%) to N. europaea ATCC 25978T (type strain) is 93.77%. This bacterium has a higher optimal growth temperature (35 degrees C) than is usually the case and tolerance up to 40 degrees C. The optimum concentration of ammonium sulfate in the medium is 303 mM, which should make it applicable for use in deodorization plants for enhancing the efficiency of deodorization. Phosphoglycerate kinase (PGK) and triosephosphate isomerase (TIM) were found to possess high specific activities (5700 and 4 x 10(5) U/mg, respectively) compared to the activities of these enzymes in strain ATCC 25978T (300 and 14 U/mg). 相似文献
108.
Natural convective heat transfer in vertical concentric pipe annuli is investigated both numerically and experimentally for a fluid having a Prandtl number of 0.7. Numerical calculations for three cases of different heating conditions for pipes (heated inner pipe, heated outer pipe, both pipes heated) are made of laminar flows for different inner‐to‐outer‐pipe diameter ratios di/do from 0.2 to 0.8. For each case, the thermal entrance length x/b at the modified Grashof numbers Gr*=102 to 5 × 105 is well correlated with Grashof number Gr* and annulus length to clearance ratio L/b. Local Nusselt numbers Nui and Nuo in the thermally fully developed region have certain constant values dependent on the diameter ratio di/do, regardless of Gr* and L/b. Average Nusselt numbers Nui and Nuo in the thermal entrance region are also independent of Gr* and L/b. © 2001 Scripta Technica, Heat Trans Asian Res, 30(8): 676–688, 2001 相似文献
109.
Yasutoshi Ohtake Tamotsu Okamoto Akira Yamada Makoto Konagai Koki Saito 《Solar Energy Materials & Solar Cells》1997,49(1-4)
Polycrystalline Cu(InGa)Se2 (CIGS) thin-film solar cells using evaporated InxSey and ZnInxSey buffer layers are prepared. The purpose of this work is to replace the chemical bath deposited CdS buffer layer with a continuously evaporated buffer layer. In this study, a major effort is made to improve the performance of CIGS thin-film solar cells with these buffer layers. The relationship between the cell performance and the substrate temperature for these buffer layers is demonstrated. Even at the high substrate temperature of about 550°C for the buffer layer, efficiencies of more than 11% were obtained. Furthermore, the I−V characteristics of the cells using these buffer layers are compared with cells using CdS buffer layers fabricated by chemical bath deposition method. We have achieved relatively high efficiencies of over 15% using both the ZnInxSey and the CdS buffer layers. 相似文献
110.