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971.
Measurements have been made of the effective thermal conductivity of a packed bed of hollow, yttria-stabilized zirconia microspheres, under vacuum and under 100 kPa of argon gas. Above 1400 K the spheres begin to sinter together. Before this occurs, the conductivity is given under vacuum by A 1 T 3 + A 2 with A 1 = 2 × 10−11 W · m−1 · K−4 and A 2 = 0.01 W · m−1 · K−1 . The thermal conductivity increases strongly with both the gas pressure and the degree of sintering of the spheres. The measured values can be fitted reasonably well by a model developed by Takegoshi et al. These results may have some applicability to the development of high-temperature thermal insulation. 相似文献
972.
对中国城市化进程中土地经济问题的几点思考 总被引:9,自引:0,他引:9
本文针对城市化进程中土地的经济重要性、土地高强度开发模式、房地产开发商的“新市镇”计划、农民集体土地使用权的出让和转让等若干土地经济问题进行了讨论和反思 ,并阐述了自己的见解。 相似文献
973.
RE Myers SW Vernon AV Carpenter AM Balshem PG Lewis TA Wolf J Hilbert LR DeFonso EA Ross 《Canadian Metallurgical Quarterly》1997,21(4):380-389
Studies done in the mid-1970s documented increased risk for respiratory cancer and leukemia among employees in a chemical company manufacturing plant where chloromethyl ethers were used in production from 1948 to 1971. In the late 1980s, the company informed current and former employees about the results of follow-up studies which showed a moderation of risk of respiratory cancer and leukemia. New data showing elevated rates of mortality from colorectal, prostate, bladder, and pancreatic cancer in the population were also reported. Via mailed correspondence, the company made a no-cost program of colorectal and prostate cancer screening available to employees upon request; and information about bladder and pancreatic cancer was made available. Thirteen percent of employees in the population indicated interest in colorectal and prostate cancer screening (response). Thirty-one percent of these responders were screened (adherence). Multivariate analyses showed that education and length of employment in the plant were positively associated with response. Being white was positively associated with response for younger workers; while among older workers being male was positively associated with response. In terms of adherence, we found that older, more highly educated workers were more likely to have a screening examination. Findings indicate that employee participation in workplace-sponsored colorectal and prostate cancer screening can vary according to worker sociodemographic factors and length of employment in areas of potential exposure. 相似文献
974.
Kazdin Alan E.; Kratochwill Thomas R.; VandenBos Gary R. 《Canadian Metallurgical Quarterly》1986,17(5):391
Suggests that clinical trials, or evaluations of psychotherapy techniques in clinical settings with patient populations, play a pivotal role in treatment research. Well-controlled psychotherapy trials provide a test of what treatment can do under conditions in which procedures such as therapist training and monitoring and the integrity of treatment are optimal. Methods designed to reduce the hiatus in how treatments are implemented, monitored, and evaluated in clinical research and practice include developing standardized assessment and treatment packages that can be implemented by practitioners, altering the manner in which clinical training is implemented and evaluated, training clinicians in strategies to evaluate their own clinical work, and conducting clinical replication case studies as a way to evaluate treatment applications in clinical practice. These alternatives combine standardization, training, evaluation, and clinical practice to help increase the generality of research findings to clinical work and to help merge research and clinical priorities. (46 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
975.
976.
建筑材料与结构耐久性实验小型人工气候室设计 总被引:4,自引:0,他引:4
吴延鹏 《建筑热能通风空调》2001,20(2):63-64
介绍一个建筑材料与结构耐久性实验系统的小型人工气候室设计概况,说明在特殊条件下空调设计的特点、技术途径和需要注意的问题。 相似文献
977.
固态硅酸盐被膜缓蚀剂在热水锅炉及空调循环水系统中的应用问题 总被引:1,自引:0,他引:1
通过对固态硅酸盐被膜缓蚀作用机理及影响因素的分析,对其在热水锅炉及空调循环水系统中的应用,提出了一些建议。 相似文献
978.
水蓄热电锅炉作为系统热源在中小型空调系统中的应用 总被引:2,自引:0,他引:2
介绍水蓄热电锅炉的应用实例、优缺点及设计中应注意的若干问题。 相似文献
979.
Johannes A. A. W. Elemans Vincent F. Slagt Alan E. Rowan Roeland J. M. Nolte 《Israel journal of chemistry》2005,45(3):271-279
The development of self-assembling catalysts, although an often-tried approach, has achieved little success so far. Toward the construction of substrate selective catalysts, we have self-assembled a porphyrin cage based upon the recognition of the templates meso-dipyridyl ( DPyP ) or meso-tetrapyridyl porphyrin ( TPyP ) by glycoluril-based receptors that are functionalized with two pendant zinc porphyrins. 相似文献
980.
以济宁医学院附院手术室为例,简要介绍了层流手术室在净化等级,气流组织等方面的特点,并分析了设计中净化标准的确定,参数的选取,机房的布置等问题。 相似文献