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991.
Argues that there is a substantial body of evidence that clearly indicates that various types of interventions can reduce the recorded criminal activity of offenders and that the treatment literature is decidedly superior in terms of effectiveness, cost efficiency, and methodological rigor to the alternative, deterrence, advocated by "nothing works" proponents (e.g., R. M. Martinson, 1976). (French abstract) (60 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Asimple unweighted means ANOVA of a 2k factorial experiment with unequal and disproportionate cell frequencies resulted in the same sums of squares and F tests as the more complex Method 1 analysis recommended by J. E. Overall et al (see record 1975-20136-001). (6 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Paul Zoller 《应用聚合物科学杂志》1978,22(3):633-641
Experimental data on the specific volume of a 50% crystalline sample of poly(tetrafluorethylene) are presented and discussed. Data points were taken along 22 isotherms spaced 5 to 30°C apart (up to 372°C) in pressure increments of 100 kg/cm2 up to 2000 kg/cm2. In addition to the melting transition and the first-order solid–solid transition near room temperature, a previously reported second-order transition near 140°C at P = 0 is observed. This transition shifts to higher temperatures with increasing pressure by about 0.015°C per kg/cm2. The melt data are discussed in detail. They can be fitted to both the empirical Tait equation, with the usual exponential temperature dependence of the Tait parameter, and to the Simha-Somcynsky hole theory (with the reducing parameters V* = 0.424 cm3/g, T* = 7906°K, and P* = 7100 kg/cm2 = 6960 bars), thus providing a test for this theory at high reduced temperatures near T? = 0.08. 相似文献
994.
Boyd D. Colin Lawrence Peter D. Bratty Paul J. A. 《IEEE transactions on bio-medical engineering》1978,(3):236-243
A model has been proposed for the generation of single motor unit potentials routinely observed in the clinical EMG examination of the normal biceps brachii muscle. A dipole representation was chosen for the single fiber activity. The motor unit was constructed from a uniform random array of single fibers. Motor unit potentials generated by this array have been observed at various distances both inside and outside the array. The effects of single fiber dipole axial dispersions on the potentials observed at increasing distances from the array have also been investigated. Motor unit potentials generated by the model have been compared with existing data from multielectrode studies in the biceps brachii. 相似文献
995.
996.
The influence of hydrostatic pressure on the tensile deformation and fracture of copper 总被引:1,自引:0,他引:1
An investigation has been made into the effects of hydrostatic pressures up to 600 MPa on the tensile deformation and fracture mechanisms of commercial copper. Fracture occurred by the normal tensile fracture mechanism involving void coalescence followed by shear tearing at pressures up to 300 MPa. At pressures in excess of 300 MPa fracture occurred entirely by a mechanism involving highly localized bands of intense shear deformation. This mechanism resulted in fracture at a chisel-point so that the natural strain to fracture at these pressures approached infinity. 相似文献
997.
Tables of electronic wavefunctions are presented for almost all heteronuclear diatomic systems which arise from combinations of the first-row atoms Li through F. These wavefunctions are obtained for the experimental (or theoretical) internuclear separation and are expansion solutions to the Restricted Hartree-Fock equations with extensive sets of Slater-type functions. The repertory includes the ground states of the systems indicated, several low-lying excited states, and a few positive and negative ions. The results are arranged into sequences for fluorides, AF, oxides, AO, nitrides, AN, etc. The calculations are, in general, restricted to states involving either closed-shell electronic configurations or open-shell configurations with only one incompletely filled open shell. Several of these systems are of doubtful existence, that is, they have not been experimentally characterized, and some should be regarded as arising only from the repulsive interaction of the two atoms involved. 相似文献
998.
Cameron K. Lyon Paul F. Knowles George O. Kohler 《Journal of the science of food and agriculture》1983,34(8):849-854
Leaf protein concentrates (LPC) were prepared in large pilot plant equipment from seven Brassica varieties grown on plots of up to 0.06 ha. Plants were harvested about a month before and after the lucerne processing season. Best yields of LPC, from leafier or forage-type species, were up to 0.9 t ha?1. Properties were as good as or better than those of LPC from lucerne. Lucerne processing procedures were modified to maximize yields from the more succulent Brassica plants. 相似文献
999.
1000.
Paul W. Schindler 《工业材料与腐蚀》1968,19(9):761-764
Determination of the gibs free energy of corrosion reactions in aqueous media The Gibbs free energy is the sum of some partial contributions, the most important of which can be calculated from the solubility constant of the solid corrosion product and the standard potential of the particular metal. Since these two quantities describe the position of heterogeneous ionic equilibria the author presents methods suitable for the investigation of sch equilibria. Depending on the standard state selected, i.e. pure water (or aqueous solutions at “infinite” dilution or solutions of inert salts of constant ionic strength) one obtains thermodynamic or stoichiometric equilibrium constants; with the latter it is possible to use, instead of activities, the respective concentrations. Using the system Zn/H2O/CO2 the author points out possible corrosion products and experimental methods. The methods used enable an approximately exact determination to be made of solubility constants and free energies of formation of simple stoichiometric corrosion products at room temperature, not, however, at higher temperatures or when corrosion products are present as solid solutions. 相似文献