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951.
In three experiments on apparent motion, subjects were to press a computer key as quickly as possible either when the apparently moving stimulus passed the midpoint of its trajectory or when it reached the endpoint. If motion is perceived as a trajectory through a series of spatial locations, and if this type of percept is the basis of deliberate responding (assumptions that can be considered Cartesian in origin), then reaction times should be faster to the midpoint than to the endpoint. In contrast to these assumptions, there was no difference between reaction times to these two points. Alternative accounts of the results are discussed.  相似文献   
952.
Main Science Center of the Russian Federation, A. A. Bochvara All-Russia Scientific-Research Institute of Standardization in Machine Engineering. Atomnaya énergiya, Vol. 79, No. 3, pp. 197–200, September, 1995.  相似文献   
953.
A. A. Bochvar All-Union Scientific-Research Institute of Standardization in Machine Engineering. Moscow Engineering Physics Institute. Translated from Atomnaya énergiya, Vol. 77, No. 2, pp. 123–129, August, 1994.  相似文献   
954.
955.
956.
Experience gained with the analysis of several thousand soil slopes in hydromechanical and civil construction is codified. A quantitative assessment is made of 12 factors and situations affecting the stability of soil slopes, and the range of application, optimal conditions, and accuracy of the computational method under consideration are indicated. Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 6, pp. 15–18, November–December, 1995.  相似文献   
957.
Nickel losses in the slag generated at Larco electric reduction furnaces (ERF) during smelting of Greek laterites account for about 20% of the total nickel of the feed. The recovery of the nickel contained in the slag as well as in its magnetic concentrate was studied under different methods. The experimental results have shown that a nickel recovery in the range of 75-90% is possible by allowing the slag to settle. Washing by low carbon steel can be performed during the final stages of the settling process as it improves the finally attained nickel recovery up to 94.4%. The simultaneous carbon reduction and settling process do not favour the Ni- recovery as the produced carbon monoxide and dioxide cause boiling of the bath which promotes the flotation of the metallic grains. In all cases a reoxidation of nickel was observed after 20min approximately. Settling of the ferronickel grains was described by a mathematical model. The model's results are in good agreement to the experimental ones for the initial 20min of the process. A modified model was elaborated combining the settling of the metallic grains with the nickel reoxidation reaction. This model describes with adequate accuracy the whole Ni- recovery process. The developed model can be proven helpful in the design of a slag cleaning step for metal recovery utilizing a slag settling furnace operating on line to the ERF.  相似文献   
958.
The β and γ decay of uranium atoms from xUO3(100 - x)[3B2O3 · MO] glass systems, where M=Sr or Pb and 0 ≤ × ≤ 20 mol%, is investigated. The γ decay data are very close to each other, for the same UO3 contents, in both the systems. The composition dependence of the β decay exhibits a lower slope in the lead borate matrix than in the strontium borate matrix. The ratio between the β activity of samples with the same uranium ion concentrations in the two investigated glass systems is a function of the x values. The results are correlated with the amount of radioactive nuclides and with the structural environments of the radionuclides. The leaching treatment in water at temperatures below 100°C evidenced no aqueous dissolution of glass samples.  相似文献   
959.
960.
Different techniques for measuring autogenous deformation in cement paste are discussed, and a newly developed dilatometer designed specially for measuring this deformation is described. A particular characteristic of the dilatometer is the encapsulation of the cement paste in corrugated moulds. This restricts moisture loss and ensures that the hardening cement paste suffers insignificant restraint. In addition, the encapsulation permits measurements to commence shortly after casting.  相似文献   
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