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961.
962.
963.
Insoluble polymer bound photosensitizers, useful for the conversion of norbornadiene (1) to quadricyclene (2), have been synthesized. An acetophenone analogue was produced by Friedel-Crafts acylation of polystyrene resin while treatment of chloromethylated resin with salicyladehyde and triethylamine produced an anlogue of benzyloxybenzaldehyde. Reaction of lithio---polystyrene resin with methyl 4-(N,N-dimethylamino)benzoate gave a ketone equivalent to 4-(N,N-dimethylamino)benzophenone (3). Quantum yields for the conversion of 1 and 2 using the polymer bound sensitizers were generally comparable to, but slightly lower than, the analogous compound in homogeneous solution. The quantum yield of polymer bound 3 was less solvent dependent than that of the homogeneous counterpart. The advantages of isolating the photosensitizer to the photochemical reactor stage of a photochemical solar energy storage device are discussed. Efficient sensitization by polymer bound photosensitizers demonstrates the feasibility of this approach. 相似文献
964.
965.
GRIP (GeneRal Interactive Processor) is a problem-oriented language which establishes a powerful and convenient communication linkage between engineer and computer. GRIP is implemented in a set of programs which provide its capabilities for command translation, on-line programming and small database management. The GRIP application program, written using the grammer of the language, provides access to one or more task specific programs and to utility resources such as numerical methods and interactive graphics packages. This paper describes the structure and function of GRIP applications which support chemical engineering education and research activities. 相似文献
966.
Some Practical System Availability Calculations 总被引:1,自引:0,他引:1
The usefulness of a recent result in system availability is displayed and discussed. Methods are presented for solving some problems which arise in the practical implementation of this result. Specifically, equations are provided for calculating the availability of a series system in which one or more components may have a surge or an installed spare. Finally, a manufacturing line efficiency model is described which has system (line) availability as one of its principal factors. 相似文献
967.
Gold Richard M.; Kapatos Gregory; Prowse James; Quackenbush Patricia M.; Oxford Terry W. 《Canadian Metallurgical Quarterly》1973,85(1):52
Performed 3 experiments on small groups (n = 2-6) of thirsty Carworth female albino rats. Cool water suppressed water intake. The suppression was apparent from the 1st min of drinking. Suppression occurred for both short (20-min) and long (100-min) daily drinking sessions, and occurred whether the water was available from a sipper tube or a bowl. When cellular hydration was delayed by giving Ss isotonic saline instead of water, the suppression by cooling was enhanced. Cool-water suppression of water intake appears to be a short-latency satiety mechanism that anticipates cellular and extracellular hydration. (27 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
968.
Research in the 1960s demonstrated the capabilities of infants and the demand characteristics of their behavior. These data, together with the failure of studies directed exclusively to parent effects on children, have led to a reformulation of socialization theory to encompass the reciprocal influences of parent and offspring. The cognitive capabilities, knowledge, and attitudes of parents assume a more important role in this theory. New research approaches are now available that can isolate parent and child effects, thus providing the foundation needed for identifying reciprocal influences. If research fills in the outline of this new perspective, and the viewpoint is communicated to parents, it should facilitate parent–child interaction. Previous theories, all too often given extreme expression in the mass media, have adversely affected the functioning of parents, either causing them to feel too much responsibility for their children's development, or leading them to mistake permissiveness for parental involvement and commitment. The reformulation should attenuate these extreme formulations, because neither of the latter is consistent with the concept of reciprocal influences. (9 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
969.
The Ellis withdrawal theory is shown to be a eubstantial improvement for predicting film thickness as compared to the previous theory for pseudo-plastic fluids. The two-term Ellis power-law theory ie shown to be a good approximation to the Ellis theory. The relative deviations between data and Ellis theory become larger at lower speeds. 相似文献
970.
Richard A. Reck 《Journal of the American Oil Chemists' Society》1968,45(1):16-18
Use of nonfatty raw materials for the production of a variety of new aliphatic chemical derivatives are discussed, including
petroleumderived olefins, which are converted by Armour Industrial Chemical Co. to so-called “β-Amines.” 相似文献