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991.
The biology of Corcyra cephalonica (Stainton) was studied under controlled conditions in the laboratory. At a constant temperature of 30°C, oviposition was influenced by relative humidity, an average of 148.9 eggs per female being laid at 70% r.h., compared with 131.8 eggs at 50% r.h. More eggs were retained in the ovaries of dead females at the lower r.h. Maize, rice and groundnuts were preferred to cowpea and cocoa for egg deposition. The incubation period was about 4 days at both humidities. Larval development was fastest at 70% r.h. (34.1 days) and slowest at 50% r.h. (43.3 days). Pupal duration was not affected by relative humidity. Development on different forms of a range of food commodities was studied. The larval period was generally shortest on brokens and meal, particularly of maize. Adult moths appeared weakly negatively phototactic and most locomotory activities were observed to take place at dusk.  相似文献   
992.
Liquid-liquid equilibrium data for two ternary systems were obtained. The experimental data were measured for cyclohexane-toluene-sulfolane at 17, 25 and 50°C, and for hexane-toluene-sulfolane at 18 and 25°C. The NTRL and UNIQUAC models were used to correlate the experimental results and to calculate the phase compositions of the ternary systems. The agreement between the experimental results and the fitted values was equally good with both of the models.  相似文献   
993.
In this paper we develop oscillators whose outputs are solid holed torus knots in real three-dimensional space. Here solid holed knots are closed trajectories on the solid holed torus where the solid holed torus is formed by three perpendicular circles revolved around one another. An electronic circuit is presented that can generate any desired solid holed torus knot.Research supported by NSF Grant MIP 87-19886.  相似文献   
994.
995.
In this second of a two-part article, we describe how the therapist's interpretations promote therapeutic progress. Any therapist behavior that is in accord with the patient's plan will be helpful to the patient, but interventions that are at cross purposes with the patient's plan will not be helpful. The implications of the plan concept for brief dynamic therapy are described and contrasted with other key technical, concepts such as transference interpretations, therapeutic alliance, and interpretive activity. The importance of understanding the patient's plan and intervening in accord with it are illustrated in several case vignettes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
996.
The generation of an LR parser consists of constructing a parse table, with one row per state (in a push-down automaton), and one column per terminal symbol. Traditionally, this is carried out row by row, with the computation of one row depending (potentially) on all the others. We present a technique for carrying out the lookahead computation of SLR (1) and LALR (1) parsers in a completely parallel fashion. Our technique performs the computation by column, rather than by row. We show that the computation is totally independent for each column, making it ideal for parallelization. The speedup factor of the technique is min (N, T), whereN is the number of processors andT is the number of terminal symbols in the user's grammar.  相似文献   
997.
DBMS technology and product offerings are changing so quickly that few practitioners can stay abreast of current trends. Vendor claims of relational capabilities and the emergence of fourth-generation languages axe not always clear indicators of what DBMS products are best for particular operating environments. In this article, six of the most frequently asked questions about current DBMS and 4GL technology are cleared up for the concerned MIS professional.  相似文献   
998.
Improving the understanding of complex molecular systems is an important and interesting use of supercomputers. Computer simulation currently plays, and will continue to play, a vital role in research in this area by acting as a guide to site-specific mutagenesis. This study explains simulations of complex molecules.  相似文献   
999.
1000.
The effect of a localized SiO2 codoping on the conversion of polycrystalline, MgO-doped Al2O3 tubes to single-crystal sapphire was investigated. Codoping with SiO2 before sintering intentionally triggered abnormal grain growth, which resulted in the full conversion of tube surfaces to single crystal without adversely affecting densification to a almost pore-free, translucent state. The degree of surface conversion was strongly dependent on experimental variables, which included furnace temperature and codoping amount. Surface-converted tubes had excellent physical properties, which included good thermal cycling resistance and optical properties superior to unconverted, polycrystalline Al2O3.  相似文献   
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