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111.
G E Blom 《Exceptional children》1966,32(6):377-383
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R. P. Clark Einar Lilja Eve Malmqvist Louis Arnaud Reid Edmund King John Downing C. M. Fleming Arnould Clausse G. de Landsheere Vernon Mallinson Paul Nash Tomio Goto M. A. Brimer Rudolf Cohen Gerhard Pause M. J. Langeveld W. E. Vliegenthart Emile Planchard 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1963,9(3):351-382
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Friedrich Edding G. W. Parkyn Renzo Titone Oskar Anweiler Frederic Lilge John Vaizey Werner Levi B. Magierska Walter Schultze Mary Ewen Ulich Ben Morris Ignacy SzAniawski G. de Landsheere M. L. Kellmer Pringle W. Lenz Rudolf Haas John Bradley Josip Lukatela M. J. Langeveld S. Wiegersma H. H. Stern H. P. Rickman 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1963,8(3-4):471-498
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The techniques described in Part I of this paper for the calculation of plastic failure loads under proportional loading are further exemplified by indicating solutions for a rectangular building frame, a Vierendeel girder, and a shed-type portal frame. A method for estimating deflections of a frame just as the collapse load is attained is then described, with some indications as to its reliability. More general conditions of loading than proportional loading are next discussed, and generalized load and failure concepts are defined. The theorems and techniques for determining critical shakedown loads under variable, repeated loading are then described and illustrated. The relation of the elastic-plastic shakedown analysis to the much simpler analysis for failure under single load applications is discussed. 相似文献
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It is very difficult, if not impossible, to remove the last traces of hypo from photographic papers by any known procedure of washing. The sulfur in the residual hypo ultimately, and especially under abnormal conditions of temperature and humidity, combines with the silver image to form yellowish brown silver sulfide. This phenomenon is known as sulfiding or “fading” of the image. The various factors which affect the rate of fading of images and the washing out of hypo from films and papers are outlined.Chemical methods of hypo elimination have been proposed from time to time but the majority of these have not been satisfactory because they tend to leave substances such as thionates in the photographic material, which are equally as difficult to wash out as hypo and which also tend to sulfide or fade the silver image. A new hypo eliminator is recommended consisting of two volatile chemicals, hydrogen peroxide and ammonia. This eliminator oxidizes the hypo to sodium sulfate, which is inert and soluble in water, while any excess eliminator evaporates on drying.Two formulas and treatments are proposed: (1) Complete elimination of hypo for use by the professional, advanced amateur, and photofinisher who demand the highest standard of photographic quality in their prints.(2) Almost complete elimination of hypo (less than o.oi milligram per square inch).Since the conditions to which prints will be subjected are rarely known in advance, use of the “complete elimination treatment” is advised in all cases. 相似文献