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161.
Fuel cell vehicles (FCVs) are expected to be commercially available on the world market in 2015, therefore, introducing hydrogen-refueling stations is an urgent issue to be addressed. This paper proposes deployment plan of hydrogen infrastructure for the success of their market penetration in the Northeastern United States. The plan consists of three-timeline stages from 2013 to 2025 and divides the designated region into urban area, suburban area and area adjacent to expressway, so that easy to access to hydrogen stations can be realized. Station is chosen from four types of stations: off-site station, urban-type on-site station, suburban-type on-site station and portable station, associated with growing demand. In addition, on-site station is used as hydrogen production factory for off-site station to save total investment. This deployment plan shows that 83% of urban residents can reach station within 10 min in 2025, and that more than 90% people especially in four major cities: Boston, New York City, Philadelphia, and Washington, D.C. can get to station within 10 min by Geographic Information System (GIS) calculation.  相似文献   
162.
The processing of metals through the application of high-pressure torsion (HPT) provides the potential for achieving exceptional grain refinement in bulk disks. Numerous reports are now available describing the application of HPT to a range of pure metals and simple alloys. Excellent grain refinement was achieved using this processing technique with the average grain size often reduced to the nanoscale range. By contrast, the development of microstructure and local hardness is different depending upon the material properties. In order to make HPT processing more practical, it is indispensable to investigate the nature of the sample characteristics immediately after conventional HPT processing. Accordingly, this report demonstrates the different models of hardness evolution using representative materials of AZ31 magnesium alloy, high-purity aluminum, and Zn–22 % Al eutectoid alloy processed by HPT. Separate models are described for the evolution of hardness with equivalent strain, and the correlation between these models is suggested by the homologous temperature of HPT processing. A special emphasis is placed on examining the numerical expression of the level of strain hardening or softening of these metals with increasing equivalent strain.  相似文献   
163.
Two sets of anvils having different surface roughness were used to systematically investigate the flow patterns developed on the top and bottom surfaces of stainless steel discs with an anvil misalignment of 100 µm during high-pressure torsion. It is shown that the flow patterns on the disc surfaces have different variation tendencies depending on whether the anvils have rough or smooth surfaces. Double-swirl flow patterns were observed on the top and bottom surfaces of discs after 1 and 5 turns when using an anvil with a smooth surface. In contrast, when using an anvil with a rough surface the double-swirl flow patterns appeared only on the top surface after 1 turn and a single swirl appeared on both surfaces after 5 turns. Hardness measurements on the top surfaces showed that discs processed using an anvil with a rough surface have greater hardness than discs processed using an anvil with a smooth surface. There was no obvious hardness difference on the bottom surfaces for discs processed using anvils with rough or smooth surfaces.  相似文献   
164.
The criticality accident that occurred on September 30, 1999 at a uranium processing plant in Tokai-mura was an unprecedented nuclear accident in Japan, not only because it caused deaths of two workers due to radiation casualty but also because it called for evacuation and sheltering indoors to nearby residents. The accident was not directly caused by failures or malfunctions of hardware but by workers’ unsafe action deviated from the approved procedure. It was a typical organizational accident in that several organizational factors worked behind. This article is to analyze various causal factors that lead to the accident, including situational factors of workers’ unsafe action that triggered the accident, operational and business management of the company, and nuclear safety regulation by the government. It also discusses problems of emergency response after the accident.  相似文献   
165.
Purpose: The effects of Rho-associated coiled-coil containing protein kinase (ROCK) 1 and 2 inhibitor, ripasudil hydrochloride hydrate (Rip), ROCK2 inhibitor, KD025 or rosiglitazone (Rosi) on two-dimension (2D) and three-dimension (3D) cultured human conjunctival fibroblasts (HconF) treated by transforming growth factor (TGFβ2) were studied. Methods: Two-dimension and three-dimension cultured HconF were examined by transendothelial electrical resistance (TEER, 2D), size and stiffness (3D), and the expression of the extracellular matrix (ECM) including collagen1 (COL1), COL4 and COL6, fibronectin (FN), and α-smooth muscle actin (αSMA) by quantitative PCR (2D, 3D) in the presence of Rip, KD025 or Rosi. Results: TGFβ2 caused a significant increase in (1) the TEER values (2D) which were greatly reduced by Rosi, (2) the stiffness of the 3D organoids which were substantially reduced by Rip or KD025, and (3) TGFβ2 induced a significant up-regulation of all ECMs, except for COL6 (2D) or αSMA (3D), and down-regulation of COL6 (2D). Rosi caused a significant up-regulation of COL1, 4 and 6 (3D), and down-regulation of COL6 (2D) and αSMA (3D). Most of these TGFβ2-induced expressions in the 2D and αSMA in the 3D were substantially inhibited by KD025, but COL4 and αSMA in 2D were further enhanced by Rip. Conclusion: The findings reported herein indicate that TGFβ2 induces an increase in fibrogenetic changes on the plane and in the spatial space, and are inhibited by Rosi and ROCK inhibitors, respectively.  相似文献   
166.
Block-type cation-exchange membranes (CEMs) have been prepared by blending poly(vinyl alcohol) (PVA) and the polyanion poly(vinyl alcohol-b-styrene sulfonic acid) at various molar percentages of cation-exchange groups to vinyl alcohol groups, Cpa, and by cross-linking the PVA chains with glutaraldehyde (GA) solution at various GA concentrations, CGA. The characteristics of the block-type CEMs were compared with random-type CEMs prepared in a previous study from the random copolymer, poly(vinyl alcohol-co-2-acrylamido-2-methylpropane sulfonic acid). At equal molar percentages of the cation-exchange groups, the water content of the block-type CEMs was less than that of the random-type CEMs. The charge density of the block-type CEMs increased with increasing Cpa and reached a maximum value. Further, the maximum value of the charge density increased with increasing CGA. The maximum charge density value of 1.3 mol/dm3 was obtained for the block-type CEM with Cpa = 3.1 mol% and CGA = 0.10 vol.%, which is almost two thirds of the value of a commercially available CEM [CMX: ASTOM Corp. Japan]. A comparison of the block-type and random-type CEMs with almost the same membrane resistance showed that the block-type CEMs had higher dynamic transport numbers than the random-type ones. The dynamic transport number and membrane resistance of the block-type CEM with Cpa = 4.0 mol% and CGA = 0.10 vol.% were 0.96 and 4.9 Ω cm2, respectively.  相似文献   
167.
The wavelength-division multiplexing (WDM) technology has been extensively studied and actually deployed as a key technology to solve global information explosions by multiplexing plural signal paths using different wavelengths into one optical fiber. Among WDM-based network architectures, this article focuses on a double-ring one for a next-generation metropolitan area network (MAN), where each node is normally equipped with two pairs of fast-tunable transmitters and wavelength-fixed receivers (TT-FR) as interface to two fibers. To enhance the network performance, additional transmitters/receivers at nodes and receiver wavelengths should be assigned optimally, so that the bandwidth bottleneck can be resolved both on nodes and fiber links. This article formulates this node configuration problem with bandwidth bottleneck resolution as a combinatorial optimization problem, and proves the NP-completeness of its decision version. Then, it presents the two-phase heuristic algorithm composed of a greedy method and a variable depth search (VDS) method. Our algorithm is evaluated through extensive network simulations, where the results support the effectiveness of this joint assignment approach.
Nobuo FunabikiEmail:
  相似文献   
168.
Tabletop dry ice coolers (three types; dome model, cap model and tripod model), which are used in kitchens and hotel banquet halls to refrigerate fresh seafood, were investigated to determine whether growth of Vibrio parahaemolyticus was inhibited by their use. On TSA plates containing 1.8% NaCl and fresh seafood (fillets of squid, pink shrimp and yellowtail), V. parahaemolyticus (O3:K6, TDH+) inoculated at 4 to 5 log CFU/sample and left at ambient temperature (25 degrees C) grew by 1.0 to 2.8 orders in 4 hours. In contrast, with tabletop coolers no significant increase in viable count occurred in 3 to 4 hours, confirming that tabletop coolers inhibited the growth of V. parahaemolyticus. The temperature in each tabletop cooler was kept below 10 degrees C for 80 to 135 min, though the CO2 gas concentration in them remained high for only a short time (0 to 75 min). It was presumed that the refrigeration function mainly contributed to growth inhibition. Our results indicate that tabletop dry ice coolers are helpful for prevention of food-borne disease due to V. parahaemolyticus in food-service locations, such as kitchens and banquet halls.  相似文献   
169.
A total of 244 milk samples collected from supermarkets in Tokyo were examined for contamination with Coxiella burnetii. C. burnetii DNA was detected in 131 (53.7%) of the samples by nested PCR. PCR-positive samples were injected into immunosuppressed A/J strain mice. Of the 22 PCR-positive milk samples tested, none resulted in isolation of C. burnetii from the mice. Heat-treatment was sufficient to inactivate C. burnetii in commercial milk. In addition, a PCR detection method for C. burnetii in chicken egg was developed. Egg yolk was added to an equal volume of 1 mol/L of NaCl phosphate buffer and homogenized for removal of protein and lipid. After centrifugal separation, the supernatant was removed, and template DNA in the precipitate was extracted using SDS, proteinase K and NaI. Using such prepared samples, 3.2 x 10(1) C. burnetii particles in 1 g of egg yolk could be detected by nested PCR. All of 200 chicken egg samples collected from supermarkets in Tokyo were negative for C. burnetii by the nested PCR method.  相似文献   
170.
Although a bioenergetic parameter is unfavorable for production of ATP (DeltapH<0), the growth rate and yield of alkaliphilic Bacillus strains are higher than those of neutralophilic Bacillus subtilis. This finding suggests that alkaliphiles possess a unique energy-producing machinery taking advantage of the alkaline environment. Expected bioenergetic parameters for the production of ATP (DeltapH and DeltaPsi) do not reflect the actual parameters for energy production. Certain strains of alkaliphilic Bacillus spp. possess large amounts of cytochrome c when grown at a high pH. The growth rate and yield are higher at pH 10 than at pH 7 in facultative alkaliphiles. These findings suggest that a large amount of cytochrome c at high pHs (e.g., pH 10) may be advantageous for sustaining growth. To date, isolated cytochromes c of alkaliphiles have a very low midpoint redox potential (less than +100 mV) compared with those of neutralophiles (approximately +220 mV). On the other hand, the redox potential of the electron acceptor from cytochrome c, that is, cytochrome c oxidase, seems to be normal (redox potential of cytochrome a=+250 mV). This large difference in midpoint redox potential between cytochrome c and cytochrome a concomitant with the configuration (e.g., a larger negative ion capacity at the inner surface membrane than at the outer surface for the attraction of H+ to the intracellular membrane and a large amount of cyrochrome c) supporting H+-coupled electron transfer of cytochrome c may have an important meaning in the adaptation of alkaliphiles at high pHs. This respiratory system includes a more rapid and efficient H+ and e- flow across the membrane in alkaliphiles than in neutralophiles.  相似文献   
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