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排序方式: 共有354条查询结果,搜索用时 31 毫秒
21.
C. Crozet M. Verdier S. Lay A. Antoni-Zdziobek 《Metals and Materials International》2018,24(4):681-692
α/γ phase transformations occurring in Fe–10Cu–xNi alloys (0?≤?x?≤?15 in mass%) were studied using X-ray diffraction, scanning electron microscopy, electron back scattered diffraction, transmission electron microscopy and chemical analysis, combining X-ray microanalysis with energy dispersive spectrometry in the scanning electron microscope and electron microprobe analysis with wavelength dispersive spectrometry. The influence of cooling rate on the microstructure was investigated using ice-brine quenching and 2 °C/min slow cooling rate performed with dilatometry. Ni addition induces metastable transformations on cooling: massive and bainitic ferrite are formed depending on the alloy composition and cooling rate. Moreover, most of the Cu phase precipitates on cooling giving rise to a fine distribution of Cu particles in the ferrite grains. For both cooling conditions, the hardness increases with increasing Ni content and a higher hardness is obtained in the quenched alloy for each composition. The change in hardness is correlated to the effect of Ni solid solution, transformation structure and size of Cu particles. 相似文献
22.
Yves-Henri Faure Chia Chun Ho Rong-Her Chen Mattieu Le Lay Jon Blaza 《Geotextiles and Geomembranes》2010
Unfavorable erosion to a revetment can affect the stability of the bank and may jeopardize the safety of adjacent structures, thus improvement work is needed to increase the stability of the revetment as well as reducing the possibility of failure. The use of geotextiles as a protection material for banks is not only environmentally friendly, but also stable in the long run. However, improper design of geotextiles may cause considerable loss of soil, which might result in failure. The actual flow behavior in revetments using geotextiles is rather complicated and can be categorized into three zones, namely, the uni-directional flow zone, the cyclic flow zone, and the tangential flow zone. In this study, a wave flume experiment was performed on model revetments using two kinds of geotextiles as the filter material to prevent erosion induced by cyclic flows. Soil migration behaviors were monitored. Furthermore, two kinds of cover blocks, riprap and concrete blocks, were carefully placed on the revetments in order to avoid puncture and abrasion of geotextiles during construction of revetments. The main purpose of this study is to elucidate the erosion control and filtration performance of soil-geotextile filtration systems under wave action. Two nonwoven needle punched geotextiles were tested. The geotextiles both have the same characteristic opening size, but have a different number of constrictions and different structures. One is a thin double-layer nonwoven material consisting of continuous filaments and the other is a thick one-layer nonwoven material consisting of short fibers. 相似文献
23.
In computed tomography, targeted (or zoomed) reconstruction is usually used to achieve high-resolution reconstruction to a small region-of-interest (ROI). This paper reports a novel targeted reconstruction method based on the recently developed differential planar computed tomography technology. With the central-slice sinogram of scanning a planar object, the primary orientation of the object is first determined for the first projection. Then by identifying the dimensions of the ROI and its offsets to the centre-of-rotation (COR), the targeted reconstruction matrix is defined, which just covers the ROI and follows its initial orientation at the scan start time. By scanning and reconstructing a small planar ROI soldered on a large planar substrate, we demonstrate the advantages of the proposed method over traditional CT, including the smaller reconstruction size and less computation time, high-resolution reconstruction and good-orientated CT image for subsequent de-layering and visualization. 相似文献
24.
Peter Robinson Dan Sheppard Richard Watts Robert Harding Steve Lay 《Computer Graphics Forum》1997,16(3):C329-C334
This paper reports on ways of using digitised video from television cameras in user interfaces for computer systems. The DigitalDesk is built around an ordinary physical desk and can be used as such, but it has extra capabilities. A video camera mounted above the desk, pointing down at the work surface, is used to detect where the user is pointing and to read documents that are placed on the desk. A computer-driven projector is also mounted above the desk, allowing the system to project electronic objects onto the work surface and onto real paper documents. The animated paper documents project is considering particular applications of the technology in electronic publishing. The goal is to combine electronic and printed documents to give a richer presentation than that afforded by either separate medium. This paper describes the framework that has been developed to assist with the preparation and presentation of these mixed-media documents. The central component is a registry that associates physical locations on pieces of paper with actions. This is surrounded by a number of adaptors that assist with the creation of new documents either from scratch or by translating from conventional hypermedia, and also allow the documents to be edited. Finally the DigitalDesk itself identifies pieces of paper and animates them with the actions described in the registry. 相似文献
25.
K. S. Harshavardhan M. Rajeswari D. M. Hwang C. Y. Chen T. D. Sands T. Venkatesan J. E. Tkaczyk K. W. Lay A. Safari L. Johnson 《Journal of Superconductivity》1992,5(6):533-537
Anisotropie surface texturing of the polycrystalline yttria-stabilized zirconia substrates, prior to YBa2Cu3O7–x
film deposition, is shown to promote in-plane (basal plane) ordering of the film growth in addition to thec-axis texturing. TheJ
c
's of the films in the weak-link-dominated low-field regime are enhanced considerably, and this result is attributed to the reduction of weak links resulting from a reduction in the number of in-plane large-angle grain boundaries.The authors acknowledge the support and encouragement of V. G. Keramidas and P. L. Key. This work was supported by the Electric Power Research Institute (Contract No. RP 7911-13). 相似文献
26.
Shan Jiang Thammanoon Sreethawong Serina Siew Chen Lee Michelle Bee Jin Low Khin Yin Win Agata Maria Brzozowska Serena Lay‐Ming Teo G. Julius Vancso Dominik Jaczewski Ming‐Yong Han 《Advanced Materials Interfaces》2015,2(3)
With the ban of tributyltin, copper‐based biocides are now widely used in antifouling coatings as the major active ingredients. Given the past experience of heavy‐metal accumulation in harbors with limited water exchange, there is a significant interest in developing copper materials that greatly reduce the amount of copper ions released into marine surroundings. In this paper, copper nanowires (NWs) encapsulated in polymer matrices are investigated as the means to control the release of copper ions and to achieve a long‐lasting antifouling effect. Very long CuNWs with high aspect ratio in organic solution are drop‐coated onto substrates to fabricate uniform thin films. They are then incorporated into an elastomeric polydimethylsiloxane (PDMS) matrix. A small amount of CuNWs in PDMS can inhibit barnacle cyprid settlement, while it exhibits low mortality to cyprids and nauplii present in the surrounding seawater environment. The low levels of copper released after 50 days suggest that the intersecting and interconnected CuNWs embedded in PDMS could potentially release copper ions continuously over a few years in seawater. This approach provides a novel platform to use hybrid materials as effective marine antifouling coatings, and may be applied to fouling release materials to enhance their antifouling properties. 相似文献
27.
This paper considers output peak controller design for discrete nonhomogeneous Markov jump systems under unit-energy disturbance. The mode-dependent output peak feedback controller is designed to ensure that the resulting closed-loop system is stochastically stable and the peak of the output is within a specified range. Furthermore, the optimal energy-to-peak gain indices of the mode-dependent and the mode-independent state feedback controllers are evaluated and compared. A numerical example is presented to illustrate the applicability of the results obtained. 相似文献
28.
29.
RM Bluthé V Walter P Parnet S Layé J Lestage D Verrier S Poole BE Stenning KW Kelley R Dantzer 《Canadian Metallurgical Quarterly》1994,317(6):499-503
A 52-year-old man was hospitalized for a right adrenal tumor which had been incidentally found by abdominal CT scan for examination of colon cancer. Laboratory and endocrine findings were within the normal limits except for increased urinary concentrations of noradrenaline and dopamine. Adrenal angiography revealed that the feeding artery of the tumor was the inferior suprarenal artery. Adrenal venous blood sampling studies detected no abnormalities in the concentrations of catecholamine, cortisol or aldosterone. Right adrenalectomy was performed and the tumor was histologically diagnosed as ganglioneuroma. Ganglioneuroma is a benign tumor originating from the sympathetic nerve ganglion. The adrenal origin of the tumor is relatively rare and 60 cases of adrenal ganglioneuroma including our case have been reported in Japan. 相似文献
30.
MM Comellas Fernández P Más Lago A Balmaseda Hechavarría L Rodríguez Lay R Palomera Puentes 《Canadian Metallurgical Quarterly》1992,44(3):228-229
The causative agent of an hemorrhagic conjunctivitis outbreak was assessed through the study of 18 conjunctival exudates using the indirect immunofluorescence technique and isolation in cell culture of human embryo fibroblasts. In addition, 395 paired serum samples were studied and Enterovirus 70 was found to be responsible for the outbreak. 相似文献