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101.
This research studies the factors which influence the tensile strength of tire cords. Five yarn samples are made by changing
the spinning conditions and viscosity to get various physical properties. Different twisting methods are introduced and the
yarns are twisted under different processing conditions for each twisting process. With the experimental results, various
analyses are performed to find the important factors in retaining strength after the twisting process. SEM and optical microscopic
photographs are taken along with some measurements to assist the analysis. 相似文献
102.
Sung Ok Sohn So Min Lee Yun Mi Kim Jeong Hyun Yeum Jin Hyun Choi Han Do Ghim 《Fibers and Polymers》2007,8(2):163-167
A durable aroma finishing for PET fabric was carried out by adopting poly(vinyl acetate) (PVAc) nanoparticles containing lavender
oil (LO) in core. Relatively small size of PVAc nanoparticles (ca. 244 nm of mean particle diameter) was expected to resist
the frictional destruction of the particles, which is frequently observed in cases of microcapsules. PVAc nanoparticles containing
LO in core were prepared by emulsification-diffusion method and their application as an aroma releasing agent for PET fabrics
was assessed through the observation of releasing profiles of LO in ethanol for experimental acceleration. Melamine-formaldehyde
(MF) microcapsules containing LO were also prepared and treated on fabrics for comparison. PVAc nanoparticles treated on PET
fabric showed higher initial releasing amount, which was ascribed to the enhanced surface area. After 2 days of releasing,
PET fabric treated with PVAc nanoparticles showed slower and more stable releasing profile and reached about 12 ppm of cumulative
release after 16 days, which was under two thirds of that with MF microcapsules. PVAc nanoparticles can be used as an agent
for durable aroma finishing of PET fabrics. 相似文献
103.
Youn?Hee?Jeon Won?Young?Jeong Jung?Woo?Park Seung?Kook?AnEmail author 《Fibers and Polymers》2003,4(4):151-155
The abrasion behavior of three kinds of warp knitted fabrics, which are normally used for upper sole of footwear, was evaluated.
We measured the changes of mechanical and structural properties of each sample as abrasion cycle increased. Each sample showed
similar trends in compression and surface properties but there were significant differences in abrasion rate among the samples.
The mechanical properties showed remarkable differences with directions. The frictional coefficient (MIU) of fabric surface
increased at the beginning of abrasion and decreased as abrasion cycles increased. The weight and thickness of the fabric
linearly decreased with abrasion cycles. The surface roughness (SMD) and the compressional resilience (RC) decreased as abrasion
cycles increased while compressional energy (WC) increased. 相似文献
104.
The antioxidant activities of six Korean rice wine (KRW) concentrates were measured by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and lipid/malonaldehyde (MA) assays. In the DPPH assay, the antioxidant activities of the KRW concentrates, including Maesilju (MSJ), Kookhwaju-1 (KHJ-1), Kookhwaju-2 (KHJ-2), Gugijaju (GGJ), Sasamju (SSJ), and Sogokju (SGJ), were 40%, 66%, 64%, 35%, 35%, and 63%, respectively. Furthermore, the concentrates inhibited the formation of MA from cod liver oil by 49%, 83%, 75%, 82%, 89%, and 90%, respectively, according to the lipid/MA assay. The sample wines were also analyzed for pH, titratable acidity, soluble solids (°Bx), and reducing sugars. The antioxidant activities of volatile extracts of the KRWs extracted by a solvent assisted flavor evaporation (SAFE) apparatus were evaluated by aldehyde/carboxylic acid assay. The volatile extracts of MSJ, KHJ-1, KHJ-2, GGJ, SSJ, and SGJ inhibited the oxidation of hexanal by 97%, 99%, 90%, 90%, 50%, and 51%, respectively. Among the nonvolatile extracts of KRWs, KHJ-2 showed the highest inhibitory effect on MA formation. 相似文献
105.
Ryu YB Jeong HJ Yoon SY Park JY Kim YM Park SJ Rho MC Kim SJ Lee WS 《Journal of agricultural and food chemistry》2011,59(12):6467-6473
Influenza A virus infections continue to pose a major threat to humans and several animal species. Neuraminidase (NA) is one of the most promising targets for the development of drugs against influenza viruses because of its critical role in the viral life cycle. During the course of a search for NA inhibitors from edible natural sources, we found that the ethyl acetate layer of ethanol extracts of Ecklonia cava showed extremely high NA-inhibitory activity (72.1% inhibition at 30 μg/mL). Bioactivity-guided fractionation of the ethyl acetate layer yielded five phlorotannins, identified as phloroglucinol (1), eckol (2), 7-phloroeckol (3), phlorofucofuroeckol (4), and dieckol (5). The inhibitory activities of these compounds (1-5) against NAs from group-1 (A/Bervig_Mission/1/18 [H1N1], A/PR/8/34 [H1N1]) and group-2 (A/Hong Kong/8/68 [H3N2], A/Chicken/Korea/MS96/96 [H9N2]) influenza A were evaluated to determine potencies and kinetic behavior. Analyses using various in vitro influenza A virus NA assays showed that all five phlorotannin derivatives were selective NA inhibitors. Of the phlorotannins, phlorofucofuroeckol (4) exhibited the most potent inhibitory activities toward group-1 NAs (IC?? values, 4.5 and 14.7 μM), whereas dieckol (5) potently inhibited group-2 NAs. Kinetic analyses indicated that compounds 1-5 were all noncompetitive. Notably, these noncompetitive inhibitors synergized with oseltamivir to enhance the NA-inhibitory effects of oseltamivir. 相似文献
106.
Journal of Plant Diseases and Protection - Plum pox virus (PPV) is one of the most destructive viral pathogens infecting stone fruit trees worldwide. As PPV causes a viral disease that requires... 相似文献
107.
Cold plasma of O2 or Ar was irradiated on hydrophobic Kapton surface to attenuate or remove the electrostatic potential. A measurement on charge
dissipation speed clarifies the obscure effect of plasma. These consequences reveal that O2 plasma etching is more effective than Ar plasma. After 30 days, the dissipation speed of accumulated charge on initially
etched sample has not changed under summar season. 相似文献
108.
Jeong Ho Song Tae Jo Kang Young Don Cho Sun Hyoung Lee Jeong Soo Kim 《Fibers and Polymers》2006,7(3):217-222
Propargyl alcohol was coupled to 2,4-hexadiyne-1,6-diol (HDD) and crystallized in the process of ultraviolet irradiation-induced
topochemical polymerization. The HDD polymer crystals were used as one component in the fabrication of organic photovoltaic
cells, in combination with fullerene as the electron acceptor. The various structures of the produced photovoltaic cells included
bilayer, trilayer, and bulk heterojunction structures. Their photovoltaic properties were analyzed in relation to crystal
structure, electrochemical properties, and band structure of the HDD polydiacetylene polymers. 相似文献
109.
Journal of Soils and Sediments - The remediation of diesel-contaminated hydrophobic soil is difficult due to the inability of aqueous phase remedial agents to infiltrate the soil. This novel... 相似文献
110.
Kim Soon-Oh Jeong Jin Young Lee Woo-Chun Yun Seong-Taek Jo Ho Young 《Journal of Soils and Sediments》2021,21(8):2755-2769
Journal of Soils and Sediments - Electrokinetic (EK) soil remediation is significantly affected by the electrode configurations. Therefore, this study was conducted to compare the performance of... 相似文献