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41.
Review of book: Media violence and its effects on aggression: Assessing the scientific evidence, by Jonathan L. Freedman. Toronto: ON: University of Toronto Press, 2002, 227 pp. Hardcover. ISBN 0-8020-3553-1. Reviewed by Claire Crooks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The ability to accurately and reliably predict whether an older adult will commit suicide has eluded clinicians and researchers. A random national sample of psychologists who work with older adults was surveyed regarding their perception of 36 risk factors for completed suicide and indirect self-destructive behavior in older adults. This study produced a profile of psychologists' assessment and treatment practices when working with suicidal older adults. Determining what psychologists consider to be the most salient risk factors for completed suicide is important in identifying a minimum standard that clinicians should follow when assessing older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The removal of Cu(II) by adsorption on fly ash has been found to be concentration, pH and temperature dependent. The kinetics of adsorption indicates the process to be diffusion controlled. The Langmuir constants have been calculated at different temperatures, and the adsorption has been found to be endothermic (ΔH = 15.652 kcal mol?1). The maximum removal is observed at pH 8.0, and variation in adsorption with pH has been explained on the basis of surface ionisation and complexation.  相似文献   
46.
用乙炔黑吸附化学聚合新工艺制备导电聚苯胺,可保持电导率不变,但转化率和堆密度提高,并明显改善了聚苯胺的颗粒形态和制膜加工性,使由其制备的聚苯胺复合正极膜和固体聚苯胺锂蓄电池的电化学性能得以改进。  相似文献   
47.
A study based on the corrosion inhibition properties of copper phthalocyanine is described. Coverage degrees of copper phthalocyanine (Cu-phcy) on ASTM-A606-4 steel, obtained by weight loss measurements, were fitted to Langmuir, Frumkin, Temkin and Flory–Huggins adsorption isotherms. A better fit to the Langmuir isotherm was obtained. The polarization curves showed that polarization of both the anodic and cathodic reactions were verified for concentrations higher than 10–4 M, indicating a mixed type action. Only the anodic reactions were polarized for lower concentrations. At high frequencies the Nyquist diagrams showed one capacitive loop attributable to double layer charging and a small one at intermediary frequencies attributable to the faradaic process of hydrogen evolution. The formation of an adsorbed film was characterized by increasing charge transfer resistance values in the low frequency range for increasing inhibitor concentrations. According to the techniques used in this study, copper phthalocyanines showed a high corrosion inhibiting efficiency for all concentrations.  相似文献   
48.
The effect of adsorption on the measurement of diffusion coefficients by the Taylor dispersion technique is investigated by modifying the governing equation to account for reversible, nonequilibrium adsorption. The resulting two-dimensional equations are solved by an explicit finite-difference technique. Experimental data for the acridine carbon dioxide system indicated that acridine adsorbs on the walls on the tubing and these data were investigated with this model. The influence of carious parameters including the number of sites and the rates of adsorption desorption was investigated by conducting a parametric sensitivity analysis on the model. It was found that adsorption of the solute on the wall of the tubing could produce an error as high as 35% on the measured diffusion coefficient compared to the actual diffusion coellicient. Examination of the influence of each of the parameters will enable Inure investigators to reduce the effect of adsorption in the measurement of diffusion coefficients by Taylor dispersion.  相似文献   
49.
TiO_2载体表面酸性的研究   总被引:5,自引:0,他引:5  
利用NH_3吸附和吡啶吸附红外技术研究TiO_2的制备条件对其表面酸性的影响。结果表明,用NH_3水中和TiCl_4溶液方法制备的TiO_2(A)表面有较强的L酸中心,中和条件对表面酸性中心数目和强度有显著影响。由TiOSO_4水解方法制备的TiO_2(B)表面具有较强的L酸中心和较弱的B酸中心,引入不同添加剂可有效地调变TiO_2载体表面的酸性。  相似文献   
50.
凝析气井井筒动态预测方法   总被引:2,自引:0,他引:2  
利用垂直管流公式,结合流体相平衡热力学闪蒸计算,运用状态方程模拟,给出凝析气井井筒动态预测新方法.根据该方法.结合油藏数值模拟计算的结果,可准确地预测不同生产时期凝析气井的井筒动态.  相似文献   
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