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101.
Robert L. Hirsch 《Journal of Fusion Energy》2002,21(2):113-116
Assuming significant technical success in the ITER project by the year 2015, it is likely that governments will want to develop a more comprehensive plan for DT tokamak fusion power commercialization. To provide a glimpse into many of the related issues, we construct conversations between the director of the U.S. fusion program and three specialists key to commercial fusion success: an environment and safety regulator, an environmentalist, and an electric generation investor. The insights from these imagined conversations will hopefully be of value as tokamak fusion power proponents plan beyond ITER. 相似文献
102.
Robert H. Doremus Denis Murphy Narottam P. Bansal William A. Lanford Chandra Burman 《Journal of Materials Science》1985,20(12):4445-4453
When liquid water contacts a zirconium-barium-lanthanum fluoride glass, at least three different processes occur. Barium and zirconium fluoride dissolve into the water, water penetrates into the glass, and zirconium fluoride crystals grow on the glass surface, in static solution. The rate of dissolution, as measured by solution analysis, is possibly controlled by diffusion in the solid surface; surface blockage and surface reactions are other possible kinetic steps involved. Diffusion in solution is not the controlling mechanism. Hydrogen profiles in the glass surface suggest that the penetration rate of water into the glass is controlled by diffusion and a surface reaction. 相似文献
103.
Common pigweed,Amaranthus hybridus L., is a favorite host of the beet army worm (BAW),Spodoptera exigua L. Chemicals extracted from homogenized pigweed with distilled water, ethanol, or dichloromethane and sprayed back on pigweed deterred oviposition by the BAW. Similarly, water extracts of frass from conspecific larvae or southern armyworm (SAW) larvae,S. eridania (Cramer), fed pigweed leaves and sprayed back on pigweed plants also deterred BAW oviposition, thus confirming that deterrence was due to plant allelochemics rather than specific compounds associated with the metabolic or excretory products of the larvae. Confirmation of the presence of oviposition-deterring chemicals in pigweed was used to explain a previously observed seasonal displacement of BAW by SAW on pigweed in the field.Mention of a commercial or proprietary product does not constitute an endorsement by the USDA. 相似文献
104.
105.
Begg Ian; Snider Andrea; Foley Finola; Goddard Robert 《Canadian Metallurgical Quarterly》1989,15(5):977
The generation effect occurs if people remember items they complete from fragments better than complete items they read. Four experiments investigate two questions. When does the effect occur, and why does it do so? Targets generated in related contexts are recognized better than read targets, and they are recalled better with the contexts as cues; the contexts are recognized equally well, and the relation between the context and target is not enhanced by generation. Furthermore, generated items exceed items read in pure lists even when read ones from the mixed list are no worse than the controls. The generation effect is real; it is not an artifact. However, there is nothing special about generation. Generating is a type of encoding, and like any other type of encoding, its effects are maximal on tests that require subjects to do again whatever they did at study. Generating makes targets distinctive by contrasting them with other relatives of the context, and, as a result, the targets enjoy benefits in later discriminations within their family. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
106.
H. E. N. Stone 《Journal of Materials Science》1987,22(5):1749-1752
The ratio of the thermal oxidation parameter to the decomposition point (T
p/T
m) is of the order of 0 85 for Y9Co7, indicating a high degree of chemical binding. The persistence of high values of this ratio has been investigated with respect to (a) other compounds in the Y-Co system, (b) replacement of cobalt in Y9Co7 by other d-e!ements, and (c) replacement of yttrium by other rare-earth elements. High ratios are found for (a) Y-Co compounds where Y/Co > 0.5, (b) Y-3d compounds with cobalt and niche! only, end (c) RE-Co compounds generally. However, there are differences in level of the ratio amongst the rare-earth compounds, from which it is inferred that the highest values coincide with full electron shells, that is, without participation of 4f electrons. Additional work is described on an effect of preparation arc-melting current 0n theT
p value for Y9Co7, and on compounds of the same pattern where both components are changed. 相似文献
107.
RM Bionta G Blewitt CB Bratton D Casper A Ciocio R Claus M Crouch ST Dye S Errede GW Foster W Gajewski KS Ganezer M Goldhaber TJ Haines TW Jones D Kielczewska WR Kropp JG Learned JM LoSecco J Matthews HS Park LR Price F Reines J Schulz S Seidel E Shumard D Sinclair HW Sobel JL Stone L Sulak R Svoboda G Thornton van der Velde JC C Wuest 《Canadian Metallurgical Quarterly》1987,36(1):30-36
108.
The total syntheses of 9(Z),12(E)- and 9(E),12(Z)-octadecadienoic acids have been carried out. A useful intermediate in both
syntheses, 8-bromo-octanoic acid, recently has become available from commercial sources. This compound has been used to expedite
the preparation of these isomers. The remaining carbon atoms were derived from propargyl alcohol along with either 1-heptyne
or acetylene and 1-bromopentane. Because the overall yield for each sequence was roughly 15% and there were no extraordinary
reaction conditions in any of the synthetic steps, the compounds could be prepared readily in multiple gram quantities. The
syntheses of the two compounds were supported by data from a variety of spectroscopic techniques. 相似文献
109.
110.
Presents some brief remarks from the editor of the Journal of Educational Psychology regarding his goals for the Journal, and noting the decline in membership in Division 15. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献