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61.
Evaluating and monitoring nucleation and growth in copper foil 总被引:1,自引:0,他引:1
Ye-Kun Lee Thomas J. O’Keefe 《JOM Journal of the Minerals, Metals and Materials Society》2002,54(4):37-41
The electrodeposition of copper foil for use in electronic materials applications is a complex and demanding process. The
specific aspects of producing and controlling the structure-property-performance requirements of the foil are important because
of the stringent demands placed on their use in printed circuit boards and similar products. In this paper, a brief review
of the electrodeposition process for raw copper foil is presented. Since electrolyte additives play such a significant role
in the copper-depositionprocess, the effects of two essential additives, chloride ion and an organic (e.g., glue or gelatine),
on the foil are described. Also, the influence of other operating parameters on the initial nucleation, growth, and subsequent
electrocrystallization are discussed. Selected characterization methods, such as polarization and scanning electron micrography
techniques, are described as a means of monitoring the process, but universally accepted methods of evaluating and controlling
the additives and foil quality during electrolysis are still being sought. 相似文献
62.
63.
Roland Gabriel Jürgen Kunz Lars Schwarze Peter Fettke Christian Scheer Franz Lehner Konrad Walser Thomas Deelmann 《WIRTSCHAFTSINFORMATIK》2006,48(3):218-222
Ohne Zusammenfassung 相似文献
64.
Thomas B. Troczynski Patrick S. Nicholson 《Journal of the American Ceramic Society》1985,68(10):277-C
Partially stabilized zirconia (PSZ) /β-alumina composites exhibit extensive non-elastic deformation during fracture. Repeated loading/stable fracture/unloading experiments were performed on chevron-notched four-point-bend specimens of the composite and pure PSZ. The energy consumption during the propagation of long cracks in the composite (∼500 J/m2 ) is 1 order of magnitude larger than for PSZ (∼50 J/m2 ). Breaking strengths of 127 MPa were obtained with a Weibull modulus of 43. 相似文献
65.
A. Neubauer 《Computing》1987,39(1):43-55
We discuss the numerical realization of an a-posteriori parameter choice for Tikhonov regularization of linear integral equations of the first kind in Hilbert scales that leads to optimal convergence rates and that does not need any information about the exact solution. Numerical examples confirm the theoretical results. 相似文献
66.
The classical black reaction developed by Camillo Golgi is shown to impregnate the tubules and fenestrations of the sarcoplasmic reticulum (SR) in striated muscle. This is a double impregnation of chromate and silver, which usually fills extracellular spaces. The method is difficult insofar as long incubation times are required, and location of the successfully “stained” SR in plastic-embedded tissue blocks is unpredictable. The light microscope is absolutely necessary to find the good regions which can then be cut from the blocks in 1-μm-thick sections and examined in the electron microscope. Stereo pairs give the best results since these resolve overlap problems common to thick sections. A variety of artifacts are illustrated which can help avoid erroneous interpretations. The Golgi-“stained” SR shows this elusive network with unsurpassed contrast and should benefit the morphological studies of muscle-membrane enthusiasts. 相似文献
67.
V. Thomas Paul S. Saroja P. Hariharan A. Rajadurai M. Vijayalakshmi 《Journal of Materials Science》2007,42(14):5700-5713
This paper presents the results of a study on the microstructural and microchemical variations in a multipass Gas Tungsten
Arc weld (GTAW) of modified 9Cr-1Mo steel. The changes brought about in the steel due to the heating and cooling cycles during
welding and the subsequent effects due to reheating effects during multipass welding are described. Detailed analytical transmission
electron microscopy has been carried to study the type and composition of the primary and secondary phases in this steel.
The systematic changes in microstructural parameters such as Prior Austenite Grain Size, martensite lath size, number density,
size and microchemistry of carbides, have been understood based on the different transformations that the steel undergoes
during the heating and cooling process. Based on the observed microstructure, an attempt has been made to identify distinct
microstructural zones and possible thermal cycles experienced by different regions of the weldment. 相似文献
68.
Steven Y. Susswein Thomas C. Henderson Joseph L. Zachary Chuck Hansen Paul Hinker Gary C. Marsden 《International journal of parallel programming》1991,20(6):453-473
Filtering algorithms are well accepted as a means of speeding up the solution of the consistent labeling problem (CLP). Despite the fact that path consistency does a better job of filtering than arc consistency, AC is still the preferred technique because it has a much lower time complexity. We are implementing parallel path consistency algorithms on multiprocessors and comparing their performance to the best sequential and parallel arc consistency algorithms.(1,2) (See also work by Kerethoet al.
(3) and Kasif(4)) Preliminary work has shown linear performance increases for parallelized path consistency and also shown that in many cases performance is significantly better than the theoretical worst case. These two results lead us to believe that parallel path consistency may be a superior filtering technique. Finally, we have implemented path consistency as an outer product computation and have obtained good results (e.g., linear speedup on a 64K-node Connection Machine 2). 相似文献
69.
This communication shows an algorithm used in the drug infusion system discussed in a recent paper1 to be incorrect. The error is corrected, and a new algorithm is presented. 相似文献
70.
J Byrne S Kienzle D Johnson G Duke V Gannon B Selinger J Thomas 《Water science and technology》2006,53(10):327-334
Long-term trends in alpine and prairie snow pack accumulation and melt are affecting streamflow within the Oldman River Basin in southern Alberta, Canada. Unchecked rural and urban development also has contributed to changes in water quality, including enhanced microbial populations and increased waterborne pathogen occurrence. In this study we look at changing environment within the Oldman River Basin and its impact on water quality and quantity. The cumulative effects include a decline in net water supplies, and declining quality resulting in increased risk of disease. Our data indicates that decreases in the rate of flow of water can result in sedimentation of bacterial contaminants within the water column. Water for ecosystems, urban consumption, recreation and distribution through irrigation is often drawn from waterholding facilities such as dams and weirs, and concern must be expressed over the potential for contaminate build-up and disproportionate potential of these structures to pose a risk to human and animal health. With disruption of natural flow rates for water resulting from environmental change such as global warming and/or human intervention, increased attention needs to be paid to use of best management practices to protect source water supplies. 相似文献