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991.
Kenji Murakami Taira Okamoto Hiroshi Matsumoto Yoshinari Miyamoto Tsuyoshi Irisawa 《Materials Science and Engineering: A》1993,160(2):181-187
Powder of a nickel-chromium alloy (about 20 wt.% chromium) was low pressure plasma sprayed onto substrates which were cooled to various extents. As the maximum temperature of the sprayed deposit was increased up to approximately 1148–1235 K during spraying, the strength of the deposit, measured on tensile test pieces machined from the deposit, increased owing to the combined effects of precipitation strengthening and enhancement of adhesion between the flattened particles composing the deposit. It is proposed that an adequate rise in temperature of the deposit during spraying improves its strength more effectively than annealing a deposit held at low temperatures during spraying, as long as the heating temperature and the heating time of these two deposits are similar to each other. 相似文献
992.
993.
Aluminium was coated on silicon nitride ceramics by a low-pressure plasma spraying method, in order to form a tight bond between aluminium and the ceramics. Aluminium nitride formed as a interfacial reaction product between the aluminium coating layer and the ceramics. Two pieces of the aluminium-coated Si3N4 ceramics were then joined using the aluminium coating layers as filler metal in a vacuum of 1.3×10–3 Pa at 973 K. The average bending strength and Weibull modulus of the joint are 340 MPa and 6.3 respectively, considerably higher than the 230 MPa and 0.9 of a Si3N4 ceramics joint brazed with an aluminum plate under the same condition. 相似文献
994.
Keiji Katsuno Akihiro Nishioka Tomonori Koda Ken Miyata Go Murasawa Yoshiko Nakaura Naoyoshi Inouchi 《Starch - St?rke》2010,62(9):475-479
The present study investigated a novel milling method for producing amorphous rice starch without adding water. A new type of milling machine was developed (termed the shear and heat milling machine (SHMM)), which is capable of applying mechanical shear and heat during the milling process. The SHMM consisted of a pair of rice mortars attached to a servomotor and a ring heater. The heater was installed on the upper mortar; the temperature of the upper mortar was monitored and controlled by a thermal controller. Wide‐angle X‐ray diffraction (WAXD) analysis was used to determine the crystallinities of starch in rice flour samples produced using the SHMM at different milling temperatures. The WAXD data for milled rice flour that had been heated exhibited no diffraction peaks. This experimental result demonstrates that the developed SHMM produces amorphous rice starch easily by milling with heating without the addition of water. The milling conditions such as the shear and heat applied can be used to control the crystallinity of starch in rice. 相似文献
995.
Full orbit-following calculation is performed for the final orbit of the lost alpha particles, showing some orbits escaping from the last closed flux surface could be detected by a concealed lost ion probe (CLIP) installed under the shadow of the original first wall surface. While both passing and trapped orbits hit the same wall panel, detecting a trapped orbit by the CLIP is easier than detecting passing orbits. Whether the final orbit is detected or not is determined by the position of the reflection point. The CLIP successfully detects the trapped orbits, which are reflected before they hit to a first wall. Then the pitch angles of the orbits at the CLIP are close to and smaller than 90°. Optimization of the position of the CLIP in terms of broader detection window is investigated. 相似文献
996.
Towards a rapid, non-contact shaping method for fibre metal laminates using a laser source 总被引:1,自引:1,他引:0
Christian Carey Wesley J. Cantwell Geoff Dearden Kenneth R. Edwards Stuart P. Edwardson Ken G. Watkins 《The International Journal of Advanced Manufacturing Technology》2010,47(5-8):557-565
Since their initial development, fibre metal laminates (FMLs) have slowly started to be used by industry, particularly the aerospace sector. One of the reasons for the relatively slow adoption of FMLs is due to the difficulties faced in shaping them to the desired geometry. Whilst traditional processes such as roll forming are effective in shaping monolithic materials, these processes could potentially destroy the mechanical properties of the composite layer. The approached investigated here uses thermal or laser forming (LF) to shape flat panels of thermosetting glass fibre based FMLs into 2D geometries. This initial empirical investigation covers the effectiveness of the various LF processes and the effects of various parameters have on the forming process. These include laser parameters such as power and velocity and material parameters such as FML lay-up strategy, fibre orientation and comparison with monolithic materials. 相似文献
997.
This paper proposes a Back Propagation (BP) neural network with momentum enhance-ment aiming to achieving the smooth convergence for aggregate volumetric estimation purpose. Net-work inputs are first selected by optically measuring the eight geometry-related parameters from the given particle image. To simplify the network structure, principal component analysis technique is applied to reduce the input dimension. The specific network structure is finalized based on both em-pirical expertise and analysis on selecting the appropriate number of neurons in hidden layer. The network is trained using the finite number of randomly-picked particles. The training and test results suggest that, compared to the generic BP network, the training duration of the proposed neural network is greatly attenuated, the complexity of the network structure is largely reduced, and the es-timation precision is within 2%, being sufficiently up to technical satisfaction. 相似文献
998.
Young Gu Lee Yun-Hyuk Choi In Seo Kee Hong Shik Shim YongWan Jin Sangyoon Lee Ken Ha Koh Soonil Lee 《Organic Electronics》2009,10(7):1352-1355
We developed a room-temperature encapsulation process based on multi-stack of ultra thin Al2O3 and polyurea layers for top-emission organic light-emitting devices (TEOLEDs). Device structure, including a capping layer for refractive-index matching and a thick polyurea buffer layer, was optimized to enhance light extraction without distorting electroluminescence spectrum. The efficiency of a TEOLED encapsulated with 5 pairs of Al2O3(50 nm)/polyurea(20 nm) layers was better than that of a glass-encapsulated TEOLED, whereas their color coordinates were almost identical. Moreover, the half-decay lifetime of a TEOLED encapsulated with 5 pairs of Al2O3/polyurea layers was 86% of that of a glass-encapsulated TEOLED. Water vapor transition rate of 5 pairs of Al2O3(50 nm)/polyurea(20 nm) layers on PET film was measured as low as 5 × 10−4 g/m2 day. 相似文献
999.
Yumiko Kaji Ryoji Mitsuhashi Xuesong Lee Hideki Okamoto Takashi Kambe Naoshi Ikeda Akihiko Fujiwara Minoru Yamaji Kenji Omote Yoshihiro Kubozono 《Organic Electronics》2009,10(3):432-436
C60 and picene thin film field-effect transistors (FETs) in bottom contact structure have been fabricated with poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS) electrodes for a realization of mechanical flexible organic FETs. The C60 thin film FETs showed n-channel enhancement-type characteristics with the field-effect mobility μ value of 0.41 cm2 V?1 s?1, while the picene thin film FET showed p-channel enhancement-type characteristics with the μ of 0.61 cm2 V?1 s?1. The μ values recorded for C60 and picene thin film FETs are comparable to those for C60 and picene thin film FETs with Au electrodes. 相似文献
1000.
Mnica Aguilera Valerio Rossini Ana Hickey Donjete Simnica Fiona Grady Valeria D. Felice Amy Moloney Lauren Pawley Aine Fanning Lorraine McCarthy Siobhan M. OMahony John F. Cryan Ken Nally Fergus Shanahan Silvia Melgar 《International journal of molecular sciences》2021,22(15)
Interactions between the intestinal microbiota, immune system and nervous system are essential for homeostasis in the gut. Inflammasomes contribute to innate immunity and brain–gut interactions, but their role in microbiota–neuro–immune interactions is not clear. Therefore, we investigated the effect of the inflammasome on visceral pain and local and systemic neuroimmune responses after antibiotic-induced changes to the microbiota. Wild-type (WT) and caspase-1/11 deficient (Casp1 KO) mice were orally treated for 2 weeks with an antibiotic cocktail (Abx, Bacitracin A and Neomycin), followed by quantification of representative fecal commensals (by qPCR), cecal short chain fatty acids (by HPLC), pathways implicated in the gut–neuro-immune axis (by RT-qPCR, immunofluorescence staining, and flow cytometry) in addition to capsaicin-induced visceral pain responses. Abx-treatment in WT-mice resulted in an increase in colonic macrophages, central neuro-immune interactions, colonic inflammasome and nociceptive receptor gene expression and a reduction in capsaicin-induced visceral pain. In contrast, these responses were attenuated in Abx-treated Casp1 KO mice. Collectively, the data indicate an important role for the inflammasome pathway in functional and inflammatory gastrointestinal conditions where pain and alterations in microbiota composition are prominent. 相似文献