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排序方式: 共有963条查询结果,搜索用时 46 毫秒
1.
David J. Lawrence Brianna L. Smith Cameron D. Collard Keyton A. Elliott Kyle L. Fakhoury Jeffery D. Mangold Anna N. Soyka 《International Journal of Hydrogen Energy》2021,46(2):1642-1655
Monolithically-integrated tandem photoanodes were fabricated on substrates consisting of epitaxial n-GaAs1-xPx (x ? 0.32) grown on n+-GaAs wafers. A p+-n junction photovoltaic (PV) cell was first formed by zinc diffusion into the n-GaAs0.68P0.32 from a deposited ZnO coating. After diffusion the ZnO serves as a transparent electrical contact to the resulting p+-GaAs0.68P0.32 surface layer. Transparent, conducting SnO2:F provides chemical and mechanical protection for the ZnO and the underlying PV cell, and it electrically connects this cell to a top BiVO4 photocatalyst layer. In some photoanodes, a WO3 thin film was interposed between the SnO2:F and BiVO4. All oxide coatings were produced by ultrasonic spray pyrolysis except WO3, which was spin coated. Unassisted (unbiased) solar water splitting was achieved, with a solar-to-hydrogen efficiency approaching 2%, without addition of any co-catalyst to the BiVO4 surface. This work can provide insights to other researchers regarding scalable, low cost approaches for the planar monolithic integration of oxide photoanode materials with PV cells to create new tandem devices. 相似文献
2.
Kyle A. Crawford
Osama K. Eyada PhD PE
《Computers & Industrial Engineering》1989,17(1-4):298-302The worldwide proliferation of fraudulent materials has brought about the need for a new approach to the control of purchased material quality. Nuclear power, defense, aerospace and many other industries are affected by the supply of poor quality clones that presume to be original replacement parts. Safety considerations abound as these highly defective materials are used in systems that are critical to the preservation of human lives. Commonly utilized quality assurance programs have not effectively stopped the influx of fraudulent materials. These programs fail to concentrate inspection efforts on materials and inspection attributes that would effectively prevent the acceptance of fraudulent materials. herein a solution is presented to this problem in the form of an expert system application. Information commonly available in industry is formulated into a knowledge based system wherein advisories are given to the user regarding key purchased material receipt inspection strategies. 相似文献
3.
D Barry J Bea D Bernd T DeFauw C Marr T McCormick JK Mitchell M O'Neil M Pittman D Strum 《Canadian Metallurgical Quarterly》1994,68(11):42, 44-46, 48
In cooperation with McManis Associates, Hospitals & Health Networks recently convened a CEO summit on physician/hospital integration activities. In the third report of a three-part series on the summit, leading health care executives discuss investor capital needs, strategic information management needs, and the management competencies required for capitated managed care success. 相似文献
4.
5.
Shubneesh Batra Nanseng Jeng Akif Sultan Kyle Picone Surya Bhattacharya Keun-Hyung Park Sanjay Banerjee David Kao Monte Manning Chuck Dennison 《Journal of Electronic Materials》1993,22(5):551-554
When dopants are indiffused from a heavily implanted polycrystalline silicon film deposited on a silicon substrate, high thermal
budget annealing can cause the interfacial “native” oxide at the polycrystalline silicon-single crystal silicon interface
to break up into oxide clusters, causing epitaxial realignment of the polycrystalline silicon layer with respect to the silicon
substrate. Anomalous transient enhanced diffusion occurs during epitaxial realignment and this has adverse effects on the
leakage characteristics of the shallow junctions formed in the silicon substrate using this technique. The degradation in
the leakage current is mainly due to increased generation-recombination in the depletion region because of defect injection
from the interface. 相似文献
6.
7.
Kyle D. Stedman 《Computers and Composition》2012,29(2):107-123
Although remixing has lately received increased scholarly attention in the rhetoric and composition community, studies commonly focus on examples of remixed objects rather than the compositional strategies used by remix composers themselves. In this study, I recount the voices of individuals who participate in online communities where videos, music, and texts from popular culture are remixed by fans: Lost Video Island, OverClocked ReMix, and Remix Redux. The aims and abilities these composers described to me constitute a developing area of digital literacy that I call remix literacy, a term that draws attention to the skills needed to create remixes that are deemed effective by communities. I find that the skills of a remix literate composer are fundamentally rhetorical, making this area of study important both for literacy scholars interested in understanding the self-sponsored activities of creative composers online and for composition instructors concerned with adapting their pedagogies to the skills I have found are needed for effective communication in fan communities. 相似文献
8.
9.
Frank C. Magne James A. Harris Robert A. Pittman Evald L. Skau 《Journal of the American Oil Chemists' Society》1966,43(9):519-524
The stepwise HBr titration method for the cyclopropenoid analysis of cottonseed oils is subject to serious inaccuracies when
applied to samples containing higher cyclopropenoid concentrations, particularly if they contain appreciable amounts of alumina-adsorbable
materials. A modification of the method is described which eliminates these sources of error. Its validity has been established
by the analysis of a wide range of synthetic compositions including compositions containing massive amounts of interfering
HBr-reactive substances and other alumina-adsorbable materials. The method with further modification can be used to analyze
glycerides with the same high degree of accuracy.
Presented at the AOCS Meeting in Houston, April 1965.
So. Utiliz. Res. Dev. Div., ARS, USDA. 相似文献
10.
The Nelder-Mead simplex method is an optimization routine that works well with irregular objective functions. For a function of $n$ parameters, it compares the objective function at the $n+1$ vertices of a simplex and updates the worst vertex through simplex search steps. However, a standard serial implementation can be prohibitively expensive for optimizations over a large number of parameters. We describe an implementation of the Nelder-Mead method in parallel using a distributed memory. For $p$ processors, each processor is assigned $(n+1)/p$ vertices at each iteration. Each processor then updates its worst local vertices, communicates the results, and a new simplex is formed with the vertices from all processors. We also describe how the algorithm can be implemented with only two MPI commands. In simulations, our implementation exhibits large speedups and is scalable to large problem sizes. 相似文献