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排序方式: 共有960条查询结果,搜索用时 15 毫秒
951.
Joël Hamada Anélie Pétrissans Julien Ruelle Frédéric Mothe Francis Colin Mathieu Pétrissans Philippe Gérardin 《Holz als Roh- und Werkstoff》2018,76(6):1669-1676
Most of the defects affecting heat-treated wood quality are often attributed to heterogeneous heat transfers in industrial kilns. Even if interspecific variability of wood has been reported to affect thermal degradation of the material, little has been reported on the effects of intraspecific variability. The aim of this work was to study the effect of intraspecific variability of silver fir (Abies alba Mill.) wood on its thermal degradation. For this purpose, wood samples were sampled along the radius of cross-sections to estimate the effect of radial position on wood thermal degradation. Sampling was carried out on discs of four trees, two resulting from dynamic growth stand and two from standard growth stand. The study was performed at different scales: at wood compartments scale involving juvenile and mature heartwood, transition zone between heartwood and sapwood and sapwood as well as at intra-ring scale. Wood samples were ground to sawdust and subjected to thermogravimetric analysis and chemical analysis. Juvenile heartwood was shown to be more sensitive to thermal degradation than other compartments. The thermal behavior of sapwood was not particularly different from that of heartwood, and the presence of extractives did not influence significantly thermal degradation. Earlywood was more sensitive to thermal degradation than latewood explaining the higher susceptibility of fast growing heartwood containing larger rings with higher contents of earlywood. 相似文献
952.
Uematsu Y Hirata K Suzuki K Iida K Kaneko R Kamata K Miyamura A 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2003,44(1):32-38
Migration from can-coatings into retorted canned food simulants (canned oil and water, 121 degrees C, 30 min) was investigated through HPLC with a fluorescence detector and evaporative light scattering detector, and by measurements of residue on evaporation and consumption of potassium permanganate. HPLC analysis revealed that migration into the canned oil was hundreds of times more than that into n-heptane (25 degrees C, 60 min, the official test conditions according to the Japanese Food Sanitation Law), whereas it was similar to the migration into isooctane-butyl acetate mixtures (60 degrees C, 60 min), and that migration into the canned water was several times more than that into water (95 degrees C, 30 min, the official test conditions). Residue on evaporation for the n-heptane extract was several-fold lower than 30 ppm (the official limit), whereas that for the isooctane-butyl acetate mixtures exceeded 30 ppm. Consumption of potassium permanganate for the canned water was 30 times higher than that for the water extract (95 degrees C, 30 min). The official test conditions for can-coatings, in particular the use of n-heptane as an oil simulant, were suggested to lead to substantial underestimation of migration into canned food. 相似文献
953.
Okochi M Sakai Y Isaji Y Nagasaki H Hamada Y Honda H 《Journal of Bioscience and Bioengineering》2011,112(6):635-637
Increased generation of reactive oxygen species (ROS) is recognized as a prominent feature of vascular dysfunction with diabetes. For self-monitoring of the risk of diabetic complications, we proposed a simple adhesion test of erythrocytes using positively charged surfaces and its adhesion property was found to correlate HbA1c level in diabetic patients. 相似文献
954.
Kentaro Yamada Tomoaki Takata Takuji Iyama Shintaro Hamada Yukari Mae Takaaki Sugihara Hajime Isomoto 《International journal of molecular sciences》2022,23(15)
A clear identification of the etiology of glomerular disease is essential in patients with diabetes. Renal biopsy is the gold standard for assessing the underlying nephrotic pathology; however, it has the risk for potential complications. Here, we aimed to investigate the feasibility of urinary fluorescence imaging using an enzyme-activatable probe for differentiating diabetic kidney disease and the other glomerular diseases. Hydroxymethyl rhodamine green (HMRG)-based fluorescent probes targeting gamma-glutamyl transpeptidase (GGT) and dipeptidyl-peptidase (DPP) were used. Urinary fluorescence was compared between groups which were classified by their histopathological diagnoses (diabetic kidney disease, glomerulonephritis, and nephrosclerosis) as obtained by ultrasound-guided renal biopsy. Urinary fluorescence was significantly stronger in patients with diabetic kidney disease compared to those with glomerulonephritis/nephrosclerosis after DPP-HMRG, whereas it was stronger in patients with nephrosclerosis than in patients with glomerulonephritis after GGT-HMRG. Subgroup analyses of the fluorescence performed for patients with diabetes showed consistent results. Urinary fluorescence imaging using enzyme-activatable fluorescence probes thus represents a potential noninvasive assessment technique for kidney diseases in patients with diabetes. 相似文献
955.
An agent-based service-oriented integration architecture for collaborative intelligent manufacturing 总被引:3,自引:1,他引:3
The rapidly changing needs and opportunities of today's global market require unprecedented levels of interoperability to integrate diverse information systems to share knowledge and collaborate among organizations. The combination of Web services and software agents provides a promising computing paradigm for efficient service selection and integration of inter-organizational business processes. This paper proposes an agent-based service-oriented integration architecture to leverage manufacturing scheduling services on a network of virtual enterprises. A unique property of this approach is that the scheduling process of an order is orchestrated on the Internet through the negotiation among agent-based Web services. A software prototype system has been implemented for inter-enterprise manufacturing resource sharing. It demonstrates how the proposed service-oriented integration architecture can be used to establish a collaborative environment that provides dynamic resource scheduling services. 相似文献
956.
H. Hamada G. O. Shonaike T. Sato S. Yamaguchi Z. Maekawa M. Koshimoto 《Polymer Composites》1994,15(5):327-333
The results of studies on bending properties of three-layer long fiber polypropylene composites are presented. Thirteen samples with glass fibers of various lengths (i.e., 13, 25, 50 mm and continuous fiber length) in the laminates were prepared by stamping. Bending properties of shorter lengths exhibited a large scatter. On substitution of the middle layer with a continuous glass fiber the scatter was reduced. These results have been explained on the basis of flow models and X-ray shadowgraphs, which showed that both slippage flow and orientation of the glass fiber during stamping are the major phenomena responsible for the scatter. 相似文献
957.
Ohru Morii Hiroyuki Hamada Zen-Ichiro Maekawa Toshio Tanimoto 《Polymer Composites》1994,15(6):408-417
This study deals with the hydrothermal effects on mechanically fastened glass fiber mat/polypropylene composite joints with different joint geometry. Three kinds of joint geometries were adopted; hole diameter was 6 mm, the length from top edge to the hole center was 18 mm (3e) and the specimen width was 12 (2 w), 18 (3w), and 30 mm (5w). The joints were immersed in hot water at 60 and 80°C. The effect of water temperature on the failure load appeared clearly in 2w3e joints. The higher water temperature induced more strength reduction. The dominant failure mode changed from the net-tension to the bearing for the original dry joints for wider specimens. The failure mode changed from multiple to net-tension only for 3w3e joints, because of a remarkable tensile strength reduction. The failure strength and the failure mode were predicted by the macroscopic failure criterion, and the characteristic experimental curves, and the FEM analysis. The predicted results agreed with experiment. 相似文献
958.
Hiroyuki Hamada Zen-Ichiro Maekawa Naoto Ikegawa Tatsuki Matsuo Masachika Yamane 《Polymer Composites》1993,14(4):308-313
Three types of glass/nylon 6 intermediate material forms-film stacking, uncommingled yarn, and commingled yarm-were selected study the correlations between the impregnating property and mechanical properties. The size of the glass fiber block to be filled with matrix and the porosity in glass fiber bundles by spearing out the fiber bundle was different in these materials. Unidirectional glass fiber reinforced thermoplastic composites were fabricated by compression molding. The being test was performed by using the three-point loading system, and the fracture behavior and the degree of impregnation were observed to examine the influence of processing conditions on the bending properties, relative to the form of the intermediate material. Bending strength increased, in accordance with the impregnating property, least in the film stacking form, second most in uncommingled yarn, and most in commingled yarn. The impregnating property was affected by the size of fiber blocks and the porosity in fiber bundles, because bending strength was improved by spreading out the fiber bundles. Commingled yarn is an excellent intermediate materials, which has both the fineness of matrix/fiber mixing and large porosity in fiber bundles. 相似文献
959.
Taniyama Akira Arai Masahiro Kosaka Makoto Hamada Takanari 《Metallurgical and Materials Transactions A》2023,54(2):745-756
Metallurgical and Materials Transactions A - The microstructural evolution and variations in the dislocation properties and the dislocation density of drawn ultralow-carbon (ULC) steel wires, which... 相似文献
960.
Tohru Morii Hiroyuki Hamada Zen-Ichiro Maekawa Toshio Tanimoto Takahiro Hirano Kazushi Haruna 《Polymer Composites》1995,16(3):240-249
This study deals with the degradation of mechanically-fastened GFRP joints immersed in hot water (80°C). The material used was randomly oriented E-glass fiber continuous strand mat with a crosslinked polyester. Three kinds of joint geometries were adopted; thickness was 3 mm, hole diameter was 6 mm, the distance from hole center to top-edge was 18 mm (3e), and specimen widths were 18 (3w), 30 (5w), and 42 mm (7w). Failure modes of original dry specimens were a function of joint geometry, The dominant failure mode of 3w3e joints was net-tension, whereas 5w3e and 7w3e joints displayed bearing failure. As degradation progressed, the dominant failure mode gradually shifted from net-tension to bearing failure. Strength reduction was marked in 5w3e and 7w3e joints, in which the dominant failure mode was bearing. Joint strength and failure mode were predicted from the combination of a macroscopic failure criterion and characteristic curves obtained from tensile testing of rectangular specimens with holes, bearing tests, and finite element analysis. Predictions agreed with experiment. 相似文献