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61.
介绍了用自然澄清法降低、回收旋涡炉渣中的铜的方法。该方法工艺简单。操作方便,不仅降低冶炼成本,同时提高了经济效益。 相似文献
62.
No authorship indicated 《Canadian Metallurgical Quarterly》2003,58(8):554
Presents the 2003 American Psychological Foundation's Gold Medal Award for Life Achievement in the Science of Psychology, which was presented to Robert Rosenthal. A biography of Rosenthal is provided, along with a selected bibliography and the text of the award citation: "For outstanding scientific contributions that have had a profound influence on research methods, empirical investigations, theory, and applications. Robert Rosenthal's seminal research on interpersonal expectancy inspired hundreds of studies with applications within and beyond psychology. His amplification of experimenter- and subject-related artifacts and his insights about ethical issues have improved the way that research is conducted. His statistical contributions are classic and wide ranging, including his body of work on meta-analysis and contrast analysis and his formulation of valuable procedures, such as the binomial effect-size display and counternull statistics. An exceptional scientist, teacher, mentor, and author, Rosenthal, with his generous and brilliant touch, has shaped the lives and work of countless others." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
63.
Doratha E Drake 《Information Processing Letters》2003,85(4):211-213
We present a linear time approximation algorithm with a performance ratio of 1/2 for finding a maximum weight matching in an arbitrary graph. Such a result is already known and is due to Preis [STACS'99, Lecture Notes in Comput. Sci., Vol. 1563, 1999, pp. 259-269]. Our algorithm uses a new approach which is much simpler than the one given by Preis and needs no amortized analysis for its running time. 相似文献
64.
Yun‐Hwei Shen 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(5):581-586
A novel strategy of sweep coagulation to treat low turbidity water is presented herein. Study findings demonstrated that an Na+‐saturated bentonite with medium cation exchange capacity (CEC) resulted in significant turbidity removal at a bentonite dosage of 30 mg dm?3. Bentonite dispersion with fully delaminated platelets tended to undergo a more porous type of coagulation with intense face‐to‐face interactions of platelets and effectively entrapped TiO2 particles in band‐type structures. This type of coagulation usually results in a large volume of settled flocs with a fluffy structure and excellent turbidity removal efficiency for sweep coagulation. The sign and magnitude of electrical charge on TiO2 particles has a minor effect on the efficiency of sweep coagulation. Copyright © 2005 Society of Chemical Industry 相似文献
65.
John E. Sohn 《The Journal of Adhesion》1985,19(1):15-27
Enhanced matrix-filler adhesion is realized after filler treatment with a surface treatment process. The hydrosol/coupling agent treatment was applied to a wide range of inorganic and organic fillers, and adhesion to a variety of matrix resins was improved. Scanning Electron Microscopy (SEM) was used to determine the locus of failure in the filled systems. The locus of failure shows the relative degree of adhesion between the filler and the polymer matrix. Significant improvement in adhesion in humid environments is also observed. 相似文献
66.
In this paper we present some preliminary results about the coupling of shallow water equations for free surface flows and Darcy equation for groundwater flows. A suitable set of interface conditions is discussed: the Beavers and Joseph formula for the bottom stress is used. An iterative algorithm to solve the coupled problem is proposed and some numerical results are presented. 相似文献
67.
陈继初 《湖南冶金职业技术学院学报》2003,(4)
会计政策选择类型在理论上大体可分为机会主义型和效率(或有效契约)型。会计政策选择具有效率性,但也为经理人员的机会主义行为打开了大门。在我国,由于企业缺乏一系列有效的激励约束机制,会计政策选择的机会主义仍然严重。为此,必须建立适合我国企业有效的激励约束机制。 相似文献
68.
介绍了天铁炼钢厂中间包水模实验原理和过程,分析了斜、直、圆三种型式挡渣墙模拟结果,提出了合理的挡渣控流方案,在生产实践中使用效果良好。 相似文献
69.
This report summarizes the panel held at the 109th Annual Convention, American Psychological Association, August 26, 2001, San Francisco. The chair was William Glover and the speakers were Samuel Gerson, Karen Maroda, and Andre Patsalides. The invited symposium was directed at discussing different perspectives related to the presence of desire in the analytic process. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
A. Alt Dr.‐Ing. H. Mertens U. Arz L. Blessing C. Berger 《Materialwissenschaft und Werkstofftechnik》2007,38(5):402-409
High cycle fatigue of bolted connections Extensive tests regarding the influences on the fatigue of bolt‐nut‐connections of preloading with torsion, of preloading with yielding, of loading with superimposed bending and of the tested lot are processed. These influences are not yet known according to VDI 2230. New testing devices were designed for these tests, which allow a far less expensive operation and may easily be used for bolts of diameters up to M100 and testing frequencies up to 1000 Hz. The validity of fatigue resistance according to VDI 2230 is specified with respect to the test results. The determined influence of the tested lots is unexpectedly high. The manufacturing process of bolts should be improved to minimize this influence. 相似文献