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141.
The production of hydrogen from water by reduced tin oxide has been examined under various experimental conditions. It has been concluded that the reactive species decomposing water is metallic tin. The coexistence of SnO2 with metallic tin enhances the rate of hydrogen production remarkably. The effect of SnO2 has been ascribed to the enlargement of surface area of tin metal by its dispersion on the surface of SnO2. Solid additives such as Pd, Pt, WO3, CuO and CaO showed a large promoting effect for hydrogen production. The effect of the additives may be explained by increase in the surface area of tin metal or by the spill-over of the activated water by additives onto the surface of SnO2 or tin metal.  相似文献   
142.
A series of resol-type phenol-formaldehyde resins with varying phenol/formaldehyde (P/F) molar ratio were investigated by infrared spectroscopy. The infrared spectroscopic data suggest that absorbance ratio of D2920, D1610, D1150, D1010, and D760 based on 1 590 cm?1 band can be used for the determination of phenol/formaldehyde molar ratio of the resins.  相似文献   
143.
Network analysis is powerful in building formal network models of various computational systems or social systems and obtaining their functions and performance exactly because of simplicity of binary relations in networks. Traditionally, it takes lots of effort in network analysis because network analysis was performed by the use of lots of numerical data in batch processing form. Effective network analysis activity, satisfying the system requirements based on consideration for such traditional manner with high cost, requires semiautomatic or computer aided man-machine facilities with interactive editing, analysis, and result viewing functions. We have developed Graphical Editing and Analysis system for Network System (Geans) on DEC PDP-11/34 minicomputer with a graphic display which enables us to edit or modify various network representations and analyze their qualitative and quantitative property, smoothly and interactively with the use of graphics and data abstraction. Geans is composed of a network editing system with effective use of a graphic display, a network data management system with systematic use of network data abstraction, a network analysis system with construction of shared library routines and specific object problem oriented routines, and a node/arc shape definition system. Geans has been applied to various network models such as a transportation analysis problem, PERT/CPM planning, Petri Net analysis and a guidance system for an urban railway network, and moreover it is being applied to other analysis areas as evolving itself.  相似文献   
144.
Summary: Spin‐drawing yarn (SDY) and high‐speed spun (HSS) fibers were produced from recycled poly(ethylene terephthalate) pellets, and the oligomer deposition on the surface of fiber in supercritical carbon dioxide fluid was compared. The oligomer deposition was obvious for SDY, which corresponded to the fact that the amount of imperfect small crystallites generated in amorphous regions through s‐CO2 treatment was much smaller for SDY as compared to that with HSS. The imperfect small crystallites generated in amorphous regions will work as a barrier to the oligomer migration. In order to suppress the deposition of oligomer for SDY, the combination of a heatset treatment and an alkaline etching was useful. At a heatset process, the oligomer migration to the surface layer tends to occur, and the layer becomes rich in oligomer. The following topochemical hydrolysis reaction at alkaline etching removes such layer. Accordingly, the total content of oligomer in etched fiber is reduced. As a result, the oligomer deposition in s‐CO2 treatment becomes not so serious. In addition, the heatset treatment gives the shrinkproof property to SDY, and the property is still retained after the alkaline etching.

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145.
This paper reports the development of membrane sensors based on an artificial lipid and plasticizers with high selectivity and sensitivity to drug bitterness by using bis(1-butylpentyl) adipate (BBPA), bis(2-ethylhexyl) sebacate (BEHS), phosphoric acid tris(2-ethylhexyl) ester (PTEH), and tributyl o-acetylcitrate (TBAC) as a plasticizer and phosphoric acid di-n-decyl ester (PADE) as an artificial lipid to optimize surface hydrophobicity of the sensors. In addition, a sensor with highly correlated bitterness sensory score was developed by blending BBPA and TBAC to detect the bitterness suppression effect of sucrose, and other bitter-masking materials. Therefore, this sensor can be used to evaluate the bitterness of various drug formulations with high accuracy. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
146.
In order to improve the remaining activity of a practically important freeze-dried enzyme, xanthine oxidase (XOD), the effects of disaccharide (sucrose and trehalose), polymer (bovine serum albumin: BSA and dextran) and a mixture of them on the loss of XOD activity during freeze-drying and subsequent storage were investigated. All samples were amorphous solids and their glass transition temperatures (Tg) were evaluated by using differential scanning calorimetry. Although dextran showed no stabilizing effect on the freeze-dried XOD, the others protected XOD from the activity loss during freeze-drying to a certain extent. It was found that the mixture of disaccharide (sucrose or trehalose) and BSA improved the XOD activity synergistically. The XOD activity of the samples decreased gradually during storage at a temperature range of between 25 and 60 °C. Samples stored at temperatures below the Tg showed a lower loss of XOD activity than those stored at just the Tg.  相似文献   
147.
The physiological effects of hydroxypropyl‐distarch phosphate (HDP) were examined in rats. Male rats were fed a fiber‐free purified diet containing gelatinized potato starch (PS, 50 g/kg diet) that was not modified chemically or gelatinized, chemically modified potato starch (CMS, 50 g/kg diet) for 21 d. PS was used as the control. Six kinds of gelatinized HDP from potato with 2 different degrees of hydroxypropylation and 3 different degrees of cross‐linking were used as CMS. The wet weight and moisture of the fecal output of the rats fed highly hydroxypropylated HDP was 70% and 30% greater, respectively, than that in the control rats. The weights of the cecal wall and content of the rats fed highly hydroxypropylated HDP were 15% and 30% higher, respectively, than those of the control rats. The apparent absorption of Mg was 15% higher in the rats fed highly hydroxypropylated HDP than in the control rats. On the other hand, the apparent absorptions of Ca, Zn, and Fe were not affected by the diet. Cross‐linking did not influence the above‐mentioned physiological effects of HDP. Fecal excretion of bile acids and the plasma cholesterol concentration were not affected by the diet. These results show that the physiological effects of HDP depend on the hydroxypropylation but not the cross‐linking.  相似文献   
148.
Lysophosphatidic acid (LPA) modulates prostaglandin (PG) synthesis via LPA receptor 3 (LPAR3) in the murine endometrium. The lack of functional LPAR3 in mice may lead to embryo mortality. In the present study, we examined the role of LPA in the bovine uterus. We confirmed that LPA is locally produced and released from the bovine endometrium. Moreover, there are enzymes involved in LPA synthesis (phospholipase (PL) D(2) and PLA2G1B) in the bovine endometrium during estrous cycle and early pregnancy. Expression of the receptor for LPA (LPAR1) was positively correlated with the expression of PGE(2) synthase (PGES) and negatively correlated with the expression of PGF(2alpha) synthase (aldose reductase with 20 alpha-hydroxysteroid dehydrogenase activity - PGFS) during early pregnancy. In vivo LPA induced P4 and PGE(2) secretion was inhibited by LPAR1 antagonist (Ki16425). The overall results indicate that LPA is locally produced and released from the bovine endometrium. Moreover, LPAR1 gene expression in the endometrium during the estrous cycle and early pregnancy indicates that LPA may play autocrine and/or paracrine roles in the bovine uterus. LPAR1 gene expression is positively correlated with the expression of the enzyme responsible for luteotropic PGE(2) production (PGES) in endometrium. In cow, LPA stimulates P4 and PGE(2) secretion. Thus, LPA in the bovine reproductive tract may indirectly (via endometrium) or directly support corpus luteum action via the increase of P4 synthesis and the increase of PGE(2)/PGF(2)(alpha) ratio. It suggests that LPA may serve as an important factor in the maintenance of early pregnancy in cow.  相似文献   
149.
The effects of fatty acid, monoacylglycerol, and polyglycerol fatty acid ester with varying chain length in their acyl chains on the extent of complex formation (complex index) and in vitro enzymatic digestibility of gelatinized potato starch were investigated. The complex index increased with increase in the concentration of the ligands (fatty acid, monoacylglycerol, and polyglycerol fatty acid ester), with the plateau in the complex index value depending on the type of ligands. In comparison of complex index among fatty acid-samples, the complex index maximum increased as the chain length increased up to octanoic acid and then decreased. In comparison of complex index among fatty acid-, monoacylglycerol-, and polyglycerol fatty acid ester-samples at each acyl chain, the complex index maximum followed the order polyglycerol fatty acid ester > monoacylglycerol > fatty acid. Fatty acid, monoacylglycerol, and polyglycerol fatty acid ester with long acyl chains greatly reduced the enzymatic hydrolysis of starch. Polyglycerol fatty acid ester with palmitic acid chains was the strongest inhibitor of starch hydrolysis, suggesting that further complex formation may occur during the hydrolysis of gelatinized starch (enzyme-annealing).  相似文献   
150.
We compared the status of carbonaceous aerosols in Tokyo before and after the implementation of a diesel vehicle regulation intended to reduce the quantity of particulate carbon from diesel engines in one of the largest scale ever attempts at vehicle exhaust control. Radiocarbon (14C) in elemental carbon (EC) and total carbon (TC) were analyzed to identify fossil fuel carbonaceous particles emitted from diesel-powered vehicles. One-sided paired-month t-tests showed no distinct difference in the absolute concentrations of particles in terms of total mass (19.5 to 18.0 microg m(-3); p = 0.321), EC (3.6 to 3.3 microg m(-3); p = 0.272), and TC (6.3 to 6.2 microg m(-3); p = 0.418) for the finest particles (d(a) < 1.1 microm) after the implementation of the regulation. The ratios of the concentrations of the chemical constituents were, however, altered after the regulation. EC/TC was significantly decreased from 56.7% to 50.2% (p = 0.039). Although it was not statistically significant, the percentage of fossil carbon in EC also decreased (67.8% to 63.8%; p = 0.104). Since EC is predominantly of combustion origin, the observed decrease was likely due to the decrease in fossil EC emissions from diesel-powered vehicles. The decrease in EC/TC after the implementation of the regulation was also likely to have resulted from attachment to diesel vehicle exhaust systems of particulate filters as required as part of the regulation by the Tokyo Metropolitan Government. The EC/TC of fossil carbon of the finest particles decreased from 66.2% to 55.2% (p = 0.066), but EC/TC of biomass carbon did not decrease but rose slightly from 43.6% to 44.5% (p > 0.5). Thus, the relative ratios of components of carbonaceous aerosol particles, such as 14C, could provide a better understanding of the atmospheric pollution status, despite short-term fluctuations, than do measurements of absolute concentrations.  相似文献   
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