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61.
The main aim of this research is to systematize the reinforced-earth wall system using the geosynthetic reinforcements in
the weathered granite backfill soils containing relatively large amount of fines with low permeability. As a staged endeavor
to accomplish this purpose, laboratory pullout tests and finite element modeling are carried out focusing on the analysis
of friction characteristics associated with interaction behaviors of the geosynthetic reinforcements composed of geogrid with
outstanding tensile resistance and geotextile with a sufficient drainage properties. In addition, drainage effects of the
geotextile laid below the geogrid are examined based on the analysis of finite difference numerical modeling. From the present
investigation, it is concluded that the geosynthetic reinforcements in the weathered granite backfills can be used to achieve
combined effects of the reduction of deformations and the increase of tensile resistance, together with drainage effects. 相似文献
62.
63.
Boong Soo Jeon 《Fibers and Polymers》2013,14(11):1927-1932
The structural properties of a plain fabric were considered using the lenticular model. The structure of a plain woven fabric can be defined in terms of warp yarn number, weft yarn number, warp fabric density, weft fabric density, warp crimp, and weft crimp. Many structural variables of the plain fabric could be calculated by the lenticular model using these terms. Also, this model can be used to explain the geometry of the flattened yarns that occur during the weaving process. Flattening factors of threads for various types of fibers were calculated, compared, and explained with the number of yarn twist. Flattening factors were found to affect the structural variables of the fabric such as fabric thickness, air permeability, and yarn crimp. Yarn crimp was also studied with variation of the structural variables of the fabric. 相似文献
64.
Seung Jae Ahn Moo Sung Lee Dae Young Lim Jung Nam Im Seung Goo Lee Ji Ho Youk Han-Yong Jeon 《Fibers and Polymers》2013,14(12):2191-2196
The permeability defined by Darcy’s law indicates the degree of ability that a fluid can flow through nonwoven media under a differential pressure in laminar flow. The permeability generally indicates the specific permeability or absolute permeability. On the other hand, if the fluid is water, the permeability indicates the hydraulic conductivity or permeability coefficient. The permeability is one of the important properties for nonwoven media and a prediction of the permeability acts as a bridge between the manufacturing technology and performance requirements. Because capillary channel theory aims to make the flow of fluid easier and more understandable, many models are based on capillary channel theory. On the other hand, the theory has a limitation in that it is unsuitable for high porosity media. In this study, a very thin downstream layer, which was suggested by Lifshutz [9], was introduced to derive a prediction model of hydraulic permeability. Needle-punched and spunbonded nonwoven fabrics with various basis weights were used in the cross-plain water permeability test. From this ‘thin layer’ model, reasonable agreement between the predicted and experimental results was obtained. 相似文献
65.
66.
Kang-Seuk Choi Soo-Jeong Kye Woo-Jin Jeon Mi-Ja Park Saeromi Kim Hee-Jung Seul Jun-Hun Kwon 《Journal of veterinary science (Suw?n-si, Korea)》2013,14(3):291-297
A recombinant hemagglutinin-neuraminidase (rHN) protein from Newcastle disease virus (NDV) with hemagglutination (HA) activity was expressed in Spodoptera frugiperda cells using a baculovirus expression system. The rHN protein extracted from infected cells was used as an antigen in a hemagglutination inhibition (HI) test for the detection and titration of NDV-specific antibodies present in chicken sera. The rHN antigen produced high HA titers of 213 per 25 µL, which were similar to those of the NDV antigen produced using chicken eggs, and it remained stable without significant loss of the HA activity for at least 12 weeks at 4℃. The rHN-based HI assay specifically detected NDV antibodies, but not the sera of other avian pathogens, with a specificity and sensitivity of 100% and 98.0%, respectively, in known positive and negative chicken sera (n = 430). Compared with an NDV-based HI assay, the rHN-based HI assay had a relative sensitivity and specificity of 96.1% and 95.5%, respectively, when applied to field chicken sera. The HI titers of the rHN-based HI assay were highly correlated with those in an NDV-based HI assay (r = 0.927). Overall, these results indicate that rHN protein provides a useful alternative to NDV antigen in HI assays. 相似文献
67.
Application of microbial stress to soybean during germination induces the accumulation of phytoalexins, which have many health benefits. In this study, the effects of stress induced by Aspergillus oryzae on the phytochemical composition of germinating soybeans were investigated, and their radical scavenging activity was compared with those of ungerminated (US) and germinated (GS) soybeans. Additionally, the antioxidant activity of coumestrol, a soybean phytoalexin, against hydrogen peroxide-induced reactive oxygen species (ROS) was investigated in HepG2 cells. A. oryzae exposure significantly decreased the total isoflavone content and induced coumestrol and glyceollin I. A. oryzae-challenged germinated soybeans exhibited the highest radical scavenging activity (IC(50) = 0.55 mg/mL) as compared to US and GS. Coumestrol exhibited significantly higher radical scavenging activity than daidzein and genistein. Furthermore, coumestrol significantly prevented hydrogen peroxide-induced ROS production and lipid peroxidation and inhibited decreases in cell viability, intracellular glutathione (GSH) levels, and superoxide dismutase (SOD) activity. These results indicate that using food-grade A. oryzae to elicit the biosynthesis of phytoalexins alters the secondary metabolite profiles of the soybeans and offers enhanced bioactivity of soybean as a functional food ingredient. 相似文献
68.
Boong Soo Jeon 《Fibers and Polymers》2012,13(1):130-134
Peirce’s fabric model has been widely used to predict the structural behavior of various plain woven fabrics. The structure
of plain woven fabric can be defined in terms of the warp yarn number, weft yarn number, warp fabric density, weft fabric
density, warp crimp, and weft crimp. The warp and weft yarn diameters are calculated from the warp and weft yarn numbers,
and the effective coefficient of the yarn diameter is defined by using this model. We have investigated structural properties,
such as the effective coefficient of the yarn diameter, yarn crimp, and fabric thickness for two different fabrics in which
the constituent yarns are assumed to be either incompressible or compressible. This model is also applied to various plain
fabrics woven from cotton, rayon, wool, linen, nylon, acetate, polyester, and silk yarns. 相似文献
69.
Surveillance and diagnosis of avian metapneumovirus (AMPV) infection typically involve measurement of serum antibodies. In the current study, eggs instead of serum samples were used for the detection of AMPV antibodies in egg-laying chicken hens by enzyme-linked immunosorbent assay (ELISA). AMPV-free commercial layer hens were experimentally challenged with AMPV strain SC1509 through intravenous or oculonasal administration. Antibody levels were determined by ELISA. AMPV antibodies were detected in egg yolks from challenged hens by 7 days postinoculation (dpi), with the peak titer at 16 dpi. Antibody levels in eggs laid at 28 dpi correlated well (r = 0.93) with sera taken 28 dpi from the same hens. In a field trial of the yolk ELISA, six broiler breeder farms were surveyed, and all tested positive for AMPV antibodies in hen eggs, although positivity varied from farm to farm. Abnormal discolored eggs collected from outbreak farms had significantly higher titers of AMPV yolk antibodies than normal eggs from the same farm, unlike clinically healthy farms, where normal and abnormal eggs had similar antibody titers. These results indicate that diagnosis of AMPV infection by yolk ELISA to detect anti-AMPV antibodies may be a suitable alternative to serologic testing. 相似文献