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排序方式: 共有1879条查询结果,搜索用时 125 毫秒
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Summary It is clearly shown that nonporous iron-manganese-copper alloys can be produced by infiltrating an iron-manganese matrix with copper or copper alloys.Additional data have been obtained on the effectiveness of copper, a copper-manganese master alloy, and brass as infiltrating materials; the feasibility of producing a nonporous iron-manganese alloy free from oxide inclusions is demonstrated.Data are presented on the formation of iron-manganese-copper alloys with different manganese contents during infiltration with copper and copper-manganese master alloys, under different infiltration conditions.The extent of phase interaction during infiltration and the condition of boundaries in alloys produced under different infiltration conditions have been investigated. 相似文献
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By evaporating undoped CdTe layers onto indium tin oxide (ITO), followed by a layer of In or CrOx, back-effect photovoltaic cells In/CdTe/ITO and CrOx/CdTe/ITO were prepared. It was shown that reducing the area of grain boundaries in CdTe, bringing the space-charge region
farther away from the defect-rich region at the CdTe/ITO interface, and employing CrOx instead of In back contacts raise the quantum efficiency of the devices to 6%. 相似文献
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L. J. Kutz PhD PE V. P. Nelson 《The International Journal of Advanced Manufacturing Technology》1991,6(4):317-327
The automated control of manufacturing devices on a common communications network is a necessity for the factory of the future.
The manufacturing automation protocol (MAP) represents a major effort by a group of companies towards meeting this need, and
apparently is becoming a standard for factory-floor communications. In this project, an ASEA 2000 robot was used with a computer-controlled
ply-cutting machine in a simulated factory sheet-metal cell to demonstrate coordinated inter- and intra-cell communications.
Both machines used a MAP network to send and receive information from the cell-controller computer, and to coordinate cell
operation. The methodology, hardware and software required to adapt the ASEA robot to the MAP network are described. This
methodology will be useful in adapting other computer-controlled manufacturing devices to MAP networks. 相似文献
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AG Brooks F Borrego PE Posch A Patamawenu CJ Scorzelli M Ulbrecht EH Weiss JE Coligan 《Canadian Metallurgical Quarterly》1999,162(1):305-313
The CD94/NKG2 receptors expressed by subpopulations of NK cells and T cells have been implicated as receptors for a broad range of both classical and nonclassical HLA class I molecules. To examine the ligand specificity of CD94/NKG2 proteins, a soluble heterodimeric form of the receptor was produced and used in direct binding studies with cells expressing defined HLA class I/peptide complexes. We confirm that CD94/NKG2A specifically interacts with HLA-E and demonstrate that this interaction is dependent on the association of HLA-E with peptide. Moreover, no interaction between CD94/NKG2A and classical HLA class I molecules was observed, as assayed by direct binding of the soluble receptor or by functional assays using CD94/NKG2A+ NK cells. The role of the peptide associated with HLA-E in the interaction between HLA-E and CD94/NKG2A was also assessed. All class I leader sequence peptides tested bound to HLA-E and were recognized by CD94/NKG2A. However, amino acid variations in class I leader sequences affected the stability of HLA-E. Additionally, not all HLA-E/peptide complexes examined were recognized by CD94/NKG2A. Thus CD94/NKG2A recognition of HLA-E is controlled by peptide at two levels; first, peptide must stabilize HLA-E and promote cell surface expression, and second, the HLA-E/peptide complex must form the ligand for CD94/NKG2A. 相似文献
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