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101.
This study aims to evaluate the effect of mechanical properties on consumers’ preference for fashion leather items, and to classify them by the mechanical properties of synthetic leather. Mechanical properties were measured by the KES-FB system and a survey of experts was conducted with a preference evaluation for various items using 15 types of synthetic polyurethane leather. More easily transformable and lighter leathers are preferred for clothing, while the leathers that have better dimensional stability are preferred for purses, bags, shoes, and boots, and those with smooth surface are preferred for furniture. Furthermore, synthetic leathers were classified into three clusters by mechanical properties. There was no difference between clusters in preference for non-clothing item, because no perception of various mechanical properties was caused by the structural characteristics of each items by design. On the other hand, for clothing items, consumers’ preferences are significantly affected by mechanical properties.  相似文献   
102.
Mechanical properties and the long-term degradation properties of the recycled PET yarns are typically lower than the virgin PET yarns due to the contaminants coming from non-PET bottles, labels and caps etc. For environmental reasons, recycling of post-consumer polyester bottles into textile fibers has become commercially attractive. We studied mechanical and chemical recycling processes and examined their effects on yarn properties such as tensile properties, thermal characteristics, hydrolysis and photo-degradation. It was found that the virgin and the chemical recycled yarns with sufficient purification show similar processability, physical and mechanical properties, and long-term degradation behavior. The results provide useful information on recycled PET yarns for processability and serviceability for the high-end use.  相似文献   
103.
Although poly(lactic acid) (PLA) possesses many desirable properties such as miscible, reproducible, nontoxic, and biodegradable properties, extremely slow crystallization rate is a weak point in comparison with other commercial thermoplastics. Addition of nucleating agents can be a good method to increase the overall crystallization rate and multi-walled carbon nanotube (MWCNT) is generally known as a good nucleating agent as well as reinforcement. MWCNT reinforced PLA nanocomposites were prepared by melt blending and the unique nucleation and crystallization behaviors of pure PLA and MWCNT/PLA nanocomposites were investigated. Slow homogeneous nucleation and crystallization behavior of the pure PLA and fast heterogeneous crystallization behavior of MWCNT/PLA nanocomposites were observed. Crystallization behavior of MWCNT/PLA nanocomposites was irrespective of cooling rate and the peculiar behavior was due to fast heterogeneous crystallization caused by the nucleating effect of MWCNT and fast PLA chain mobility.  相似文献   
104.
Mechanical properties of chopped carbon fiber (CF) reinforced PC/ABS composites were investigated. Tensile strength and elastic modulus of the composites were enhanced with increasing CF contents. On the contrary, impact strength of the composite was decreased with increasing CF fraction. Film insert molding was introduced in order to improve impact strength. Film insert molded composite specimens have higher impact strength than conventional injection molded composite specimens because inserted film acted as a cushion to absorb the impact energy. Large warpage which was observed after molding and known as a disadvantage of the film insert molded part can be prevented by controlling the amount of filled CFs. Therefore, fiber reinforcement and film insert molding can be applied simultaneously to reduce warpage of the film insert molded part and enhance impact strength of the CF reinforced composite.  相似文献   
105.
Volatile compounds emanating from three cultivars of cooked rice milled to different degrees (0, 8, and 30% by weight) were compared to ascertain their site of origin and the effect of pigmentation on synthesis. The cultivars tested were Ilpumbyeo (traditional white rice), Heugjinjubyeo (black pigmented), and Jeogjinjubyeo (red pigmented). In total, 29, 38, and 27 volatile compounds were identified in dehulled, unmilled Ilpumbyeo, Heugjinjubyeo, and Jeogjinjubyeo, respectively. Significant quantitative and qualitative differences were found among the cultivars in their volatile profiles. 2‐Acetyl‐1‐pyrroline, guaiacol, 1‐nonanol, 3‐octen‐2‐one, 1,2‐dimethoxybenzene, pyridine, and pyrrole were found only in Heugjinjubyeo and phenylacetaldehyde only in Jeogjinjubyeo. Removal of the bran, partial endosperm, and pigment qualitatively and quantitatively affected the volatile compounds formed, with certain volatiles higher in unmilled rice (0% milling), indicating the pericarp and aleurone layer (bran) as their primary site of origin. Volatiles emanating from the 8 and 30% milled samples indicated the outer and middle endosperm (8%) and core endosperm (30%) as the primary sites of origin. Therefore, differences in chemical composition with location within the grain appear to account for the quantitative and qualitative variation in volatile synthesis.  相似文献   
106.
107.
This study investigated the effects of increasing water temperature (22–30 °C) on the physiological stress response and immunity of goldfish, Carassius auratus, and the ability of green light-emitting diode (LED) irradiation or melatonin injections to mitigate this temperature-induced stress. To evaluate the effects of either green-wavelength LED light or melatonin on stress in goldfish, we measured plasma triiodothyronine (T3), thyroxine (T4), and thyroid hormone receptor (TR) mRNA expression; plasma cortisol and glucose; and immunoglobulin M (IgM) and lysozyme mRNA expression. The thyroid hormone activities, TR mRNA expression, and plasma cortisol and glucose were higher in goldfish exposed to high-temperature water, but were lower after exposure to melatonin or green-wavelength LED light. Lysozyme mRNA expression and plasma IgM activity and protein expression were lower after exposure to high water temperatures and higher after melatonin or green-wavelength LED light treatments. Therefore, high water temperature induced stress and decreased immunity; however, green-wavelength LED light and melatonin treatments mitigated the effects of stress and enhanced immunity. The benefits of melatonin decreased with time, whereas those of green-wavelength LED treatment did not.  相似文献   
108.
Sesame (Sesamum indicum L.) is an important edible oil crop. Meteorological factors such as temperature, rainfall, and the amount of solar radiation determine the yield potential of sesame. To identify phenotypic diversity and to infer genotypic backgrounds in a collection of 250 sesame germplasm accessions, we classified the germplasm based on variation in morphological traits using principal component (PC) and cluster analysis. The sesame germplasm was grouped based on five PCs, which accounted for 82.3% of total variation. The first PC (PC1) was positively correlated with days to flowering, days to maturity, and number of capsules per plant, whereas the second PC (PC2) was negatively correlated with all characteristics except capsule-bearing stem length. The third component (PC3) was highly positively correlated with capsule length and plant height. We constructed a scatter diagram of the first two PCs (PC1 vs. PC2), revealing four distinct groups of eigenvectors. Most sesame germplasm was widely distributed among Groups I, II, III, and IV. Group III showed a wide range of distribution in the diagram. Otherwise, the distribution of the 250 germplasm accessions was more compact in a scatter diagram of PC1 vs. PC3 compared with PC1 vs. PC2. Groups I, II, III, and IV contained 142, 102, 2, and 3 sesame germplasm accessions, respectively. The two germplasm in Group III were collected from different regions, as were the three germplasm in Group IV. The results show that the distribution of sesame origin is wider than the regions examined in view of phenotypic diversity.  相似文献   
109.
Lack of bone formation-related health problems are a major problem for the aging population in the modern world. As a part of the ongoing trend of developing natural substances that attenuate osteoporotic bone loss conditions, dioxinodehydroeckol (DHE) from edible brown alga Ecklonia cava was tested for its effects on osteoblastogenic differentiation in MC3T3-E1 pre-osteoblasts. DHE was observed to successfully enhance osteoblast differentiation, as indicated by elevated cell proliferation, alkaline phosphatase activity, intracellular cell mineralization, along with raised levels of osteoblastogenesis indicators at the concentration of 20 μM. Results suggested a possible intervening of DHE on the bone morphogenetic protein (BMP) signaling pathway, according to elevated protein levels of BMP-2, collagen-I, and Smads. In addition, the presence of DHE was also able to raise the phosphorylated extracellular signal–regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) levels which are also activated by the BMP signaling pathway. In conclusion, DHE is suggested to be a potential bioactive compound against bone loss that could enhance osteoblastogenesis with a suggested BMP pathway interaction.  相似文献   
110.
The combined use of cytokines has shown synergistic and/or additive effects in controlling several viral infections of livestock animals. However, little is known concerning the practical use of chicken cytokine combinations to control avian diseases. Here, we investigated the antiviral efficacy of oral co-administration of chicken interferon-α (chIFN-α) and chicken interleukin-18 (chIL-18) using attenuated Salmonella enterica serovar Typhimurium in chickens infected with avian influenza virus (AIV) H9N2. Our results demonstrate that oral co-administration of S. enterica serovar Typhimurium expressing chIFN-α and chIL-18 produced a greater alleviation of clinical signs caused by respiratory infection with AIV H9N2 in chickens, when compared to administration of S. enterica serovar Typhimurium expressing either chIFN-α or chIL-18 alone. Mortality, clinical symptom severity, and feed and water intake were used to access treatment effectiveness. This enhancement of antiviral immunity was further confirmed by evidence of reduced rectal shedding and decreased replication of AIV H9N2 in several different tissues of challenged chickens including trachea, lung, cecal tonsil, and brain. Furthermore, oral co-administration of chIFN-α and chIL-18 more efficiently modulated the immune responses of chickens against AIV H9N2 by enhancing both humoral and Th1-biased cell-mediated immunity, compared to single administration of either construct. Therefore, our results suggest that the combined administration of two chicken cytokines, chIFN-α and chIL-18, using attenuated S. enterica serovar Typhimurium as an oral carrier, provides an effective means for controlling respiratory disease caused by AIV H9N2 infection.  相似文献   
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