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71.
George Owusu David B. Dreisinger Ernest peters 《Metallurgical and Materials Transactions B》1995,26(1):5-12
Liquid sulfur-zinc sulfate solution interfacial tensions and liquid sulfur-zinc sulfate solution-zinc sulfide (marmatite)
contact angles were measured in the absence and presence of surface-active agents. Interfacial tensions measured varied between
54 ± 1 mN/m in the surfactant-free system and 20 ± 1 mN/m in the presence of a surfactant. The liquid sulfur-zinc sulfide
mineral-zinc sulfate solution contact angle varies between 80 ± 5 deg, in the absence of any surfactant, and 148 ± 5 deg,
depending on the surfactant used. The surface-active agents were used as dispersants for sulfur in bench-scale zinc pressure-leaching
experiments. The observed extent of zinc extraction depends on the surfactant and varies from 40 to 96 pct. 相似文献
72.
This paper is mainly concerned with the Identification of an embryonic product platform from a family of products whose composition, configuration and characteristics are represented by Attributed Graphs. The problem becomes that of identifying the largest isomorphic sub-graph with the highest similarity. An algorithm is proposed for solving this problem together with several novel concepts. 相似文献
73.
74.
We consider multistage automatic transfer lines with unreliable stages, finite interstage buffer storages, and possible scrapping of workpieces. It is assumed that the first stage never idles and the last stage never becomes blocked. Assuming that uptimes and downtimes of a stage are geometrically distributed, an approximate model is developed to compute different performance measures of the transfer line. The results obtained through the approximate model are compared to the exact results for three-stage transfer lines and to simulation results for longer transfer lines. It is observed that the approximate results are good in almost all cases considered. 相似文献
75.
George Grant Fiona Greer Norma H. McKenzie Arpad Pusztai 《Journal of the science of food and agriculture》1985,36(5):409-414
In a series of 10-day pair feeding experiments it was found that the nutritional value of diets containing beans was essentially the same for rats aged between 30 and 123 days. Thus net protein utilisation (NPU) values of 25–39 on diets containing Processor bean (35 g protein kg?1) + egg albumin (65g protein kg?1) were obtained. As food intakes were considerably reduced when rats were fed diets containing more than 35g protein kg?1 of Processor bean, the measurement of protein utilisation became increasingly more difficult. The severe disruption of the brush borders of duodenal and jejunal enterocytes, originally observed when bean-containing diets were fed to young (30-day-old) rats was also found with rats up to the age of 120 days on similar diets. Similarly, the development of circulating anti-lectin antibodies in the animals showed no age dependence within the age limits investigated. It was also shown that oral immunisation did not protect the rats from the effects of toxicity and that the immune response was a result of continuous absorption of lectin throughout the feeding period. Thus the extent and the mechanism of toxicity of Phaseolus vulgaris bean lectins were found not to be dependent on the age or maturity of the animal. 相似文献
76.
Reviews the book, Empirical studies of psychoanalytical theories, volume 1 by Joseph Masling (1983). Many psychoanalytic clinicians are comfortable functioning in the clinical world, using experience-near data. Many others are comfortable in the metapsychological world, using more experience-distant concepts. Some are even able to apply theory to practice, and modify one based on their experience of the other. But the bridge between the two, the middle-level described by Mayman, which represents the empirical joining of the theoretical and clinical, operationalized in the form of research which can inform either the clinical or the theoretical, is an area of lessened comfort for many. It is to this middle-level that Masling's book addresses itself, presenting examples of a wide variety of psychoanalytic research projects. Some are studies of psychoanalytic theory and others of psychoanalytic therapy; some are more empirical and others are more theoretical, some are original and others are reviews of already published material; but all provide an empirical grounding for practice. Stricker reviews the major findings and contributions of each of the seven chapters, and concludes with some general comments about psychoanalytic research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
This paper describes the basis for a new method of type synthesis of spatial mechanisms with the use of single-loop structural groups having zero degrees of freedom. Applying the binary system, the value 0 is used for R (revolute) and 1 is used for P (prismatic) pairs. The five-link spatial groups are described by codes both in the binary and decimal systems. All other groups are reduced to the basis of five-link spatial groups. In these cases two-degree-of-freedom and three-degree-of-freedom kinematic pairs are transformed to one-degree-of-freedom pairs, and these transformations are also described by codes in the binary and decimal systems. This method of coding can be programmed for digital computation and applied towards the automatic type synthesis in the design of spatial mechanisms. The system is equally clear for alphanumeric or for graphical display. To the designer it defines the diagram of the mechanism, pointing out the frame, the mobile links, the types of the kinematic pairs and their mutual disposition in the mechanism configuration. 相似文献
78.
Hartouni E.P. Jensen D.A. Klima B. Kreisler M.N. Rabin M.S.Z. Uribe J. Church M. Gara A. Gottschalk E. Hylton R. Knapp B.C. Sippach F.W. Stern B. Wiencke L. Christian D. Gutierrez G. Holmes S.D. Strait J.B. Wehmann A. Avilez C. Correa W. Rosales A. Forbush M. Huson F.R. White J. 《IEEE transactions on nuclear science》1989,36(5):1480-1484
A novel technique for both online and offline computation is presented. With this technique, a reconstruction analysis in elementary particle physics, otherwise prohibitively long, has been accomplished. It will be used online in an upcoming Fermilab experiment to reconstruct more than 100000 events per second and to trigger on the basis of that information. The technique delivers 40 gigaoperations per second, has a bandwidth on the order of gigabytes per second, and has a modest cost. An overview of the program, details of the system, and performance measurements are presented 相似文献
79.
George Chryssolouris James E. Pierce Kristian Dicke 《International Journal of Flexible Manufacturing Systems》1992,4(3-4):309-330
This paper introduces a generic decision-making framework for assigning resources of a manufacturing system to production tasks. Resources are broadly defined production units, such as machines, human operators, or material handling vehicles; and tasks are activities performed by resources. In the specific context of FMS, resources correspond to individual machines; tasks correspond to operations to be performed on parts. The framework assumes a hierarchical structure of the system and calls for the execution of four consecutive steps to make a decision for the assignment of a resource to a task. These steps are 1) establishment of decision-making criteria, 2) formation of alternative assignments, 3) estimation of the consequences of the assignments, and 4) selection of the best alternative assignment. This framework has been applied to an existing FMS as an operational policy that decides what task will be executed on which resource of this FMS. Simulation runs provide some initial results of the application of this policy. It is shown that the policy provides flexibility in terms of system performance and computational effort. 相似文献
80.