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81.
A radial immunodiffusion enzyme assay for the detection and quantitation of antibodies to pseudorabies virus in swine sera was developed and the methods were standardized. The assay combined the principle of radial immunodiffusion with enzyme-linked immunosorbent assay. Quantitation of pseudorabies virus antibody titers was determined by measuring the diameter of a colored circular zone after overnight incubation of antibody with antigen. The specificity and sensitivity of the radial immunodiffusion enzyme assay were compared with that of the standard virus-neutralization test, and the results were determined to be correlated highly (r = 0.694, P less than 0.0001). The assay also appeared to be highly reproducible and simple to perform.  相似文献   
82.
Groundwater–stream water exchange and mixing in a hyporheic zone were examined using the water chemistry data and multivariate statistical analyses. The study area was the Munsan stream of agricultural area in Paju, Korea. Three rounds of water samplings (August, September, and November, 2008) were conducted for five monitoring nests along the stream flow, with each having three different-depth piezometers in the streambed, one surrounding groundwater well and one stream water point. The chemical compositions of hyporheic water were controlled by those of the groundwater and stream water. The factor analysis identified four main factors that explain 67 % of total variance of the water chemistry data and also revealed that the parameters responsible for water quality variances were mainly related to rainfall, anthropogenic activities, and dissolution of carbonate minerals. The cluster analysis produced a few different groups in August (3 groups), September (4 groups), and November (4 groups), respectively, which showed that the water quality parameters of the three water bodies were very different and the hyporheic water showed a different mixing of the stream water and groundwater at each monitoring point.  相似文献   
83.
Poly(vinyl alcohol) (PVA)/Ag-zeolite nanocomposite hydrogels were prepared by UV irradiation using PVA solution mixed with Ag-zeolite nanoparticles. Physical properties and changes in morphology of the PVA/Ag-zeolite hydrogels were investigated. The PVA/Ag-zeolite hydrogels were prepared at a PVA concentration of 9 wt% with a UV irradiation distance of 15 cm, where gel fraction and swelling ratio were optimized. Hardness of the PVA/Ag-zeolite hydrogels decreased with increasing amounts of Ag-zeolite, reaching that of soft elastomer when the amount of Ag-zeolite was 5 % by weight. The PVA/Ag-zeolite hydrogels showed strong antimicrobial activities against Staphylococcus aureus and Klebsiella pneumoniae, inducing a reduction of bacteria of over 99.9 % at a Ag-zeolite content of 3 wt%.  相似文献   
84.
N-Vinylcarbazole (VCZ) was solution-polymerized in tetrahydrofuran (THF) at 25, 35, and 45 °C using a room temperature initiator, 2,2′-azobis(2,4-dimethylvaleronitrile) (ADMVN); the effects of amount of solvent, polymerization temperature, and initiator concentration were investigated. On the whole, the experimental results corresponded to predicted ones. Room polymerization temperature using ADMVN proved to be successful in obtaining poly(N-vinylcarbazole) (PVCZ) of high molecular weight with small temperature rise during polymerization, nevertheless of free radical polymerization by azoinitiator. The polymerization rate of VCZ in THF was proportional to the 0.47 power of ADMVN concentration. The molecular weight was higher and the molecular weight distribution was narrower with PVCZ polymerized at lower temperatures. For PVCZ prepared in THF at 25 °C using ADMVN concentration of 0.00005 mol/mol of VCZ, weight-average molecular weight of 221,000 was obtained, with polydispersity index of 2.05, and degree of lightness converged to about 99 %.  相似文献   
85.
The optimum conditions for producing rice starch enriched in slowly digestible and resistant fractions by citric acid treatment determined by a response surface methodology (RSM) model equation, were: reaction temperature, 128.4 °C; reaction time, 13.8 h; and citric acid, 2.62 mmol/20 g starch. The slowly digestible and resistant starch fractions of the optimally acid-treated rice starch totalled 54.1%, which was 28.1% higher than the control. The slowly digestible and resistant fractions of the acid-treated rice starch did not differ significantly after heat treatment, whereas those of raw rice starch decreased by 49.6–63.8%, depending on the type of heat treatment (cooking at 100 °C or autoclaving). The slowly digestible fraction of the acid-treated starch increased by 8.9–14.2%. After autoclaving, the glucose response of the acid-treated starch was lower than untreated starch, but similar to that of Novelose 330. After heat treatment, the rate of blood glucose decrease was slower for the acid-treated starch than for Novelose 330. Compared to raw rice starch, the acid-treated starch exhibited increases in apparent amylose content, blue value, dextrose equivalent, cold-water solubility and transmittance, and decreases in wavelength of maximum absorbance, viscosity, and gel-forming ability.  相似文献   
86.
In order to investigate the effects of cross-sectional shapes on the sound characteristics of polyester fibers, 10 specimens were woven into a twill structure made of round, hollow, triangular, u-shape, cruciform, and composite cross-sectional (▴/▴, ()/▴,Y y) fibers. Their rustling sounds were recorded, and their sound spectra were obtained from FFT analysis. Physical sound parameters (LPT, ΔL, Δf) and Zwicker’s psychoacoustic parameters of the loudness(Z), sharpness(Z), roughness(Z), and fluctuation strength(Z) were calculated from the sound spectra. According to noncircular cross-section fibers, the hollow shaped fiber had the highest value of LPT, ΔL, loudness(Z), and fluctuation strength(Z). The triangular shaped fiber had a lower value of LPT, ΔL, loudness(Z), and roughness(Z) than those of the round shaped fiber. Among composite cross-section fibers, C1 (▴/▴) and C3 (Y y) had higher values of LPT, ΔL, Δf, and loudness(Z) but C2 (()/▴) had lower values. Also the LPT, ΔL, sharpness(Z), and roughness(Z) values of different denier were similar to each other, but the Δf and loudness(Z) values increased as the denier increased.  相似文献   
87.
The combined seeding and cropping of non-leguminous and leguminous cover crops during the cold fallow season is recommended as an important agronomic practice to improve total biomass productivity and soil fertility in mono-rice (Oryza sativa L.) cultivation system. However, application of plant residues as green manure can increase methane (CH4) emission during rice cultivation and affect rice quality and productivity, but its effects are not well examined. In this field study, the mixture of barley (Hordeum vulgare R.) and hairy vetch (Vicia villosa R., hereafter, vetch) seeds with 75 % recommended dose (RD 140 kg ha?1) and 25 % RD (90 kg ha?1), respectively, were seeded after rice harvesting in late November, 2010, and harvested before rice transplanting in early June 2011. Total aboveground biomass was 36 Mg ha?1 (fresh weight basis with 68 % moisture content), which was composed with 12 Mg ha?1 of barley and 24 Mg ha?1 of vetch. In order to determine the optimum recycling ratio of biomass application that can minimize CH4 emission without affecting rice productivity, different recycling ratios of 0, 25, 50, 75, and 100 % of the total harvested biomass were incorporated as green manure 1 week before rice transplanting in a typical temperate paddy soil. The same rates of chemical fertilizers (N–P2O5–K2O?=?90–45–58 kg ha?1) were applied in all treatments. Daily mean CH4 emission rates and total CH4 fluxes were significantly (p?<?0.05) increased with increasing application rates of cover crop biomass. Rice productivity also significantly (p?<?0.05) increased with biomass application, but the highest grain yield (53 % increase over the control) was observed for 25 % recycling. However, grain quality significantly (p?<?0.05) decreased with increasing cover crop application rates above 25 % recycling ratio, mainly due to extended vegetative growth periods of rice plants. Total CH4 flux per unit grain yield, an indicator used to simultaneously compare CH4 emission impact with rice production, was not statistically different between 25 % biomass recycling ratio and the control but significantly increased with increasing application rates. Conclusively, the biomass recycling ratio at 25 % of combined barley and vetch cover crops as green manure might be suitable to sustain rice productivity without increasing CH4 emission impact in mono-rice cultivation system.  相似文献   
88.
Air-classified wheat flour was dry-coated with microparticulated rice flour (30%, db) and/or microparticulated soybean hulls (up to 10%, db) using a hybridization system, and the physical properties of the dry-coated wheat flour were examined. The composite wheat flours exhibited the higher water-holding capacity but lower swelling power and oil-holding capacity than their counterpart mixtures. In pasting viscosity, the composites of wheat and rice flours had substantially lower values for peak viscosity and breakdown than did pure wheat flour. The incorporation of soybean hulls to the composites of wheat and rice flours further reduced the peak viscosity. The composites with rice flour and soybean hulls showed slightly higher melting (gelatinization) temperatures but lower melting enthalpy compared to the counterpart mixtures. By using the composite flours for the deep-fat fried doughnut preparation, the oil uptake could be substantially reduced by approximately 30%, in comparison to pure wheat flour or the mixture samples. The composite wheat flours with microparticulated rice flour and soybean hulls produced dough matrices with improved compactness and cell structure, which were attributed to the reduced fat uptake during frying.  相似文献   
89.
Variability in the diet breadth of two sympatric mudskippers Periophthalmus modestus and P. magnuspinnatus in the tidal flats of Suncheon Bay, Korea, was compared. The analysis of 494 P. modestus and 455 P. magnuspinnatus specimens revealed that both were carnivores, consuming mainly gammarid amphipods, polychaetes, insects, and crabs. However, adult P. modestus consumed greater proportions of polychaetes whereas P. magnuspinnatus ate more crabs. The diets of both species showed ontogenetic changes in diet; smaller individuals of both species consumed harpacticoid copepods and gammarid amphipods, whereas larger fishes of both species fed mainly on different preys. The stomach content index (SCI) of both species underwent significant size-related and diel changes; the values of both species were higher in the larger size classes and during the late afternoon. Levin’s index of diet breadths of both species were lower during the day than at night, indicating high prey selection during the daytime. Non-metric multi-dimensional scaling ordination emphasized that the dietary compositions of the smaller individuals of both species showed some obvious similarities, with dietary similarity gradually reducing with increasing fish size. This indicates that the two species consume gradually different types of prey as they grow, that is, resource partitioning may be occurring between larger P. modestus and P. magnuspinnatus.  相似文献   
90.
In order to provide a fundamental understanding of the cleanroom garment failure, we interviewed the manufacturers and the customers of the garment and studied its modes and mechanism under the simulated and real service conditions. The interviews revealed that the air-born particle was the most critical factor for the failure. The test showed that the abrasion between the fabrics influenced significantly on the air-born particle generation. As the garment was used repeatedly, the number of the air-born particles increased in the oscillating modes. The microscopic study explained the airborn particle generation mechanism.  相似文献   
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