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41.
采用电子探针,图象分析仪、差质变分析仪和X射线衍仪定量研究了Ni在球铁中的分布和Ni铸态球铁组成相比例奥氏体中含碳量以及贝氏体转变TTT曲线线的影响,结果表明,Ni在球铁中呈连续负偏析,其加入可以影响球铁组成上比例,并使粤氏体中含碳量和贝氏体转变孕育期期增加。 相似文献
42.
红外热成象技术可以有效地用于股骨头坏死疾病的诊断和针刺治疗效果的评价,效果优于其它常规方法。 相似文献
43.
Reviews the book, Child sexual abuse: Critical perspectives on prevention, intervention, and treatment edited by Christopher R. Bagley and Ray J. Thomlison (1991). This book is a compilation of a series of literature reviews originally commissioned by Health and Welfare Canada in 1987 and completed in 1988. The individual papers included in this edited version represent a cross section of Canadian academicians, clinicians, and case workers who are integrally involved in the policies and practices regarding child sexual abuse in Canada. The work provides a comprehensive perspective on prevention at the primary, secondary, and tertiary levels. The list of authors is impressive in terms of their expertise and experience. At a time when numerous books on child sexual abuse are appearing on the market, it is nice to see a book that has some unusual aspects. Aside from its distinctly Canadian perspective, the book addresses several important, yet frequently ignored, topics. The book provides an up-to-date review of several core issues: conceptualization of the problem, prevention strategies, impact of sexual abuse, investigative interviewing, treatment outcome studies, and treatment issues for child molesters. The more unique topics include a review of the strategies used to evaluate prevention programs, prevalence rates among a number of special populations, the role of medical practitioners in preventing and intervening in child sexual abuse, and sexual abuse and exploitation among disabled individuals. Overall, I can recommend this book for clinicians and researchers in Canada and elsewhere who are interested in child sexual abuse. This compilation of literature reviews highlights the leading role that Canadian social service agencies have taken in developing programs for sexually abused children and their families. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
44.
本文简要介绍了国外在开发超酸性气体过程中遇到的材料选择、腐蚀监测、水化物堵塞、超酸性气的处理和加工等问题所采取的措施和办法。 相似文献
45.
Javier M. Grau JosM. Bisang 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1992,53(1):105-110
This paper describes the parameters that are important in the industrial practice of silver removal from photographic fixers. The experiments were performed under potentiostatic control using synthetic solutions. The current efficiency was analysed as a function of the cathodic potential taking into account the deposit quality. A cathodic potential of ?0.5 V against a saturated calomel electrode is recommended. The conditions to prevent the darkening of the electrodeposit were investigated. The determination of silver concentration in the solution was made by direct potentiometry. The results obtained with synthetic fixers were corroborated by making the silver deposition from commercial fixers in an electrochemical reactor with rotating cylinder electrode intercalated in an electrolytic flow circuit in order to simulate practical conditions. 相似文献
46.
淀粉液化液灭酶方法的研究 总被引:5,自引:1,他引:4
某些情况下淀粉液化液需要严格控制液化的程度 ,因此需要及时终止残余淀粉酶的活性。实验用降低液化液 pH值、升高温度、以及两者并用等 3种方法结束液化反应过程 ,实验结果可作为工业生产过程参考。 相似文献
47.
Burns John W.; Kubilus Amanda; Bruehl Stephen; Harden R. Norman; Lofland Kenneth 《Canadian Metallurgical Quarterly》2003,71(1):81
Changes in maladaptive cognitions may constitute therapeutic processes of multidisciplinary pain programs. A cross-lagged panel design was used to determine whether (a) early-treatment cognitive change predicted late-treatment outcome index change, but not vice versa; and (b) these effects remained significant with depression change controlled. Ninety chronic pain patients, in a 4-week multidisciplinary program, completed measures of catastrophizing, pain helplessness, depression, pain, interference, and activity level at pre-, mid-, and posttreatment. With depression changes controlled, early-treatment catastrophizing and pain helplessness changes predicted late-treatment outcome index changes, but not vice versa; early-treatment depression changes predicted late-treatment activity changes, but not vice versa. Findings advance understanding of pain treatment process and suggest that negative cognition changes may indeed affect improvements in treatment outcome. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
用光学及电子显微镜(SEM.TEM)观察不同热处理的40Cr 钢的冲击及断裂韧性断口、及金相组织,阐明其间相互关系;断口结构可反映断裂特征,组织情况;细化晶粒提高强度、塑性和冲击韧性,但却减少脆断的特性距离 l 因而降低 K_(1c)模;减少碳(杂质)偏聚而使其呈较均匀地分布,从而减少可诱发塑坑的较粗大的碳(杂质)化合物的析出,即增加塑坑的间距 di 以及增加塑断组成物。从而都可增加断裂临界应变 ef,都可以提高 K_(1c)40Cr 复合热处理既靠先超高温淬、回火以减少碳(杂质)偏聚,改善其分布,以反增加位错马氏体从而提高 K_(1c),也靠后淬、回火细化晶粒而提高强度、塑性和冲击韧性,各自发挥长处达到强韧化。 相似文献
49.
Zhufang Liu Mohammad Shamsuzzoha Earl T. Ada W. Matthew Reichert David E. Nikles 《Journal of power sources》2007
Well-dispersed Pt nanoparticles with controlled size and narrow size distribution were prepared by polyalcohol reduction of platinum acetylacetonate, using oleylamine as a capping agent. The particle size was varied from 3.5 nm to 11.5 nm by decreasing the amount of oleylamine added in the synthesis. Size selection of the as-prepared particles by solvent fractionation yielded nearly monodispersed Pt particles. The as-prepared particles were loaded on a carbon support by physical deposition, but showed no electrocatalytic activity due to the oleylamine bound to the particle surface. The particles were activated for electrocatalysis after heating the particles in air at 185 °C for 5 h, conditions that gave no particle-sintering and no oxidation. Cyclic voltammetry showed that the particles after the heat treatment in air were electrocatalytically active for methanol oxidation. The smaller 3.5 nm and 4.0 nm Pt particles had a higher intrinsic activity for methanol oxidation, but a lower tolerance to CO poisoning, compared with 6.0 nm, 9.5 nm and 11.5 nm particles. CO-stripping results suggest that CO is more easily oxidized on larger Pt particles. 相似文献
50.
酶法提取树莓汁的研究 总被引:8,自引:1,他引:7
本试验以澳洲红、早红、美国22三个品种树莓为原料,通过不同的酶处理方法来制原果汁,优选适于制汁的品种和酶处理方法。 相似文献