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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
961.
Evans Jonathan St. B. T.; Handley Simon J.; Over David E. 《Canadian Metallurgical Quarterly》2003,29(2):321
The authors report 3 experiments in which participants were invited to judge the probability of statements of the form if p then q given frequency information about the cases pq, p?q, ?pq, and ?p?q (where ? = not). Three hypotheses were compared: (a) that people equate the probability with that of the material conditional, 1 - P(p?q); (b) that people assign the conditional probability, P(q/p); and (c) that people assign the conjunctive probability P(pq). The experimental evidence allowed rejection of the 1st hypothesis but provided some support for the 2nd and 3rd hypotheses. Individual difference analyses showed that half of the participants used conditional probability and that most of the remaining participants used conjunctive probability as the basis of their judgments. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
962.
A. V. Lyutetskii N. A. Pikhtin S. O. Slipchenko N. V. Fetisova A. Yu. Leshko E. G. Golikova Yu. A. Ryaboshtan I. S. Tarasov 《Technical Physics Letters》2003,29(4):290-293
Separate confinement InGaAsP/InP laser heterostructures were grown by metalorganic-hydride vapor-phase epitaxy. High-power single-mode laser diodes of mesastripe design based on these heterostructures operate in a wavelength interval of 1.7–1.8 μm with a maximum continuous room temperature output power of 150 mW. The single-mode lasing regime is maintained up to an output power level of 100 mW. 相似文献
963.
964.
We apply a bifurcation-theoretic approach to the standard Moore–Greitzer compressor model in effort to understand a curious phenomenon. When one forces the actuator to respond sluggishly to commanded inputs, performance of the controller improves dramatically. We show that the behavior can be explained via Hopf–Hopf interactions of surge and rotating stall. Also, we argue that there is a broad class of controllers which possess the general dynamic features responsible for the surprising effectiveness of sluggish actuators. 相似文献
965.
Yu. F. Patrakov E. S. Pavlusha N. I. Fedorova Yu. A. Strizhakova 《Solid Fuel Chemistry》2008,42(1):10-13
The results of the thermal solution of oil shale in benzene in a flow unit under supercritical conditions are reported. It was found that the conversion of shale organic matter into liquid products increased by a factor of 2.5 with an increase in the solvent pressure from 5 to 15 MPa. 相似文献
966.
D. Ballutaud F. Jomard T. Kociniewski E. Rzepka H. Girard S. Saada 《Diamond and Related Materials》2008,17(4-5):451-456
Hot filament and microwave plasma CVD micro- nanocrystalline diamond films are analysed by visible and ultra-violet excitation source Raman spectroscopy. The sample grain size varies from 20 nm to 2 μm. The hydrogen concentration in samples is measured by SIMS and compared to the grain size, and to the ratio of sp2 carbon bonds determined by Raman spectroscopy from the 1332 cm− 1 diamond peak and the sp2 1550 cm− 1 G band. Hydrogen concentration appears to be proportional to the sp2 bonds ratio. The 3000 cm− 1 CHx stretching mode band intensity observed on the Raman spectra is decreasing with the G band intensity. Thermal annealing modifies the sp2 phase structure and concentration, as hydrogen outdiffuses. 相似文献
967.
M. Guerioune Y. Amiour W. Bounour O. Guellati A. Benaldjia A. Amara N. E. Chakri M. Ali-Rachedi D. Vrel 《International Journal of Self-Propagating High-Temperature Synthesis》2008,17(1):41-48
Aiming at preparation of shape memory alloys (SMAs), we explored the SHS of Cu1 − x
Zn1 − y
Al1 − z
alloys (0.29 < x < 0.30, 0.74 < y < 0.75, and 0.83 < z < 0.96). The most pronounced shape memory effect was exhibited by the alloys of the following compositions (wt %): (1) Cu(70.6)Zn(25.4)Al(4.0),
(2) Cu(70.1)Zn(25.9)Al(4.0), and (3) Cu(69.9)Zn(26.1)Al(4.0). The effect of process parameters on the synthesis of CuZnAl
alloys was studied by XRD, optical microscopy, and scanning electron microscopy (SEM). The grain size of CuZnAl was found
to depend on the relative amount of the primary CuZn and AlZn phases. Changes in the transformation temperature and heat of
transformation are discussed in terms of ignition intensity and compaction. Mechanism of the process depends on the level
of the temperature attained relative to the melting point of components. At the melting point of AlZn, the process is controlled
by the solid-state diffusion of AlZn into a product layer. The ignition temperature for this system depends on the temperature
of the austenite-martensite transformation in CuZnAl alloys. The composition and structure of the products was found to markedly
depend on process parameters. The SHS technique has been successfully used to prepare a variety of SMAs.
相似文献
968.
Ezequiel R. Soulé Guillermo E. Eliçabe Roberto J. J. Williams 《Polymer Bulletin》2008,60(2-3):417-423
An unexpected experimental finding is reported where the primary morphology developed during polymerization-induced
phase separation in a rubber-modified thermoplastic practically disappears at high conversions. This process
was evidenced by light scattering (LS) and scanning electron microscopy (SEM) for a particular composition
of solutions of polyisobutylene oligomers (PIB) in isobornylmethacrylate (IBoMA), during the free-radical
polymerization of the monomer. The primary phase separation produced a dispersion of domains rich in PIB
containing significant amounts of the monomer (IBoMA). Polymerization of the monomer in these domains occurred
at high overall conversions producing the filling of dispersed domains with a PIBoMA-PIB blend that could
not be distinguished from the matrix. Under these conditions the final material had the appearance of a
homogeneous blend. 相似文献
969.
P. S. Gordienko V. A. Kolzunov L. G. Zorina T. A. Kaidalova S. B. Yarusova 《Theoretical Foundations of Chemical Engineering》2008,42(5):680-683
The possibility of processing fluorine-containing wastes of fluorite ore, which include fluorite, calcite, quartz, and anorthite, has been investigated. A manufacturing flow chart of the complex processing of the ore waste materials with the production of sodium fluoride, alumina, soda ash, and raw materials suitable for the production of Portland cement and wollastonite is suggested. 相似文献
970.
V. N. Babak T. B. Babak L. P. Kholpanov 《Theoretical Foundations of Chemical Engineering》2008,42(6):852-867
Mass transfer with solvent evaporation in the vapor-liquid two-phase film evaporators used for the removal of undesirable
impurities from liquid solutions at low pressure is studied. The average concentrations of solution components in the falling
liquid film are determined. The most efficient operating conditions for impurity removal, in which the resistance to mass
transfer is concentrated in the liquid phase, are found.
Original Russian Text ? V.N. Babak, T.B. Babak, L.P. Kholpanov, 2008, published in Teoreticheskie Osnovy Khimicheskoi Tekhnologii,
2008, Vol. 42, No. 6, pp. 654–670. 相似文献