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国家粮储库屋面防水APP卷材施工技术 总被引:1,自引:0,他引:1
针对国家粮食储备库的特点,就屋面防水APP卷材热熔法施工的施工准备及工艺流程进行了介绍,提出了具体的施工技术要点及质量通病的防治措施,取得了良好的施工效果。 相似文献
33.
DP Kiel RH Myers LA Cupples XF Kong XH Zhu J Ordovas EJ Schaefer DT Felson D Rush PW Wilson JA Eisman MF Holick 《Canadian Metallurgical Quarterly》1997,12(7):1049-1057
Previous studies of the vitamin D receptor (VDR) polymorphisms and bone mineral density (BMD) have suggested that there may be differences in calcium absorption among groups of women with different VDR genotypes, and that the association may be stronger in younger women. To investigate the association between the VDR polymorphisms and BMD, this study was undertaken in the Framingham Study Cohort and a group of younger volunteers. Subjects from the Framingham Study (ages 69-90 years) included those who underwent BMD testing and who had genotyping for the VDR alleles (n = 328) using polymerase chain reaction methods and restriction fragment length polymorphisms with BsmI (B absence, b presence of cut site). A group of younger volunteer subjects (ages 18-68) also underwent BMD testing and VDR genotyping (n = 94). In Framingham Cohort subjects with the bb genotype, but not the Bb or BB genotypes, there were significant associations between calcium intake and BMD at five of six skeletal sites, such that BMD was 7-12% higher in those with dietary calcium intakes greater than 800 mg/day compared with those with intakes < 500 mg/day. The data also suggested that BMD was higher in persons with the bb genotype only in the group with calcium intakes above 800 mg/day. No significant differences were found in the Framingham Cohort for age-, sex-, and weight-adjusted BMD at any skeletal site between those with the BB genotype and those with the bb genotype regardless of 25-hydroxyvitamin D levels or country of origin. In the younger volunteers, BMD of the femoral neck was 5.4% higher (p < 0.05) in the bb genotype group compared with the BB group and 11% higher (p < 0.05) in males with the bb genotype compared with the BB group. There were no significant differences at the lumbar spine. In this study, the association between calcium intake and BMD appeared to be dependent upon VDR genotype. The findings of an association between dietary calcium intake and BMD only in the bb genotype group suggests that the VDR genotype may play a role in the absorption of dietary calcium. Studies that do not consider calcium intake may not detect associations between VDR genotype and BMD. In addition, the association between VDR alleles and BMD may become less evident in older subjects. 相似文献
34.
The strip element method (SEM) is used to investigate wave scattering by rectangular flaws in anisotropic laminated plates. The plates containing flaws are divided by junctions into domains in which the SEM is applied. For each domain, SEM equations are obtained which give a relationship between the traction and displacement vector on the vertical boundaries. A set of equations which gives a relationship between the traction and displacement vector on the junctions is then obtained by assembling the SEM equations for all the domains. This set of equations is solved by using the conditions on the junctions. Scattered wave fields in the frequency domain for isotropic and composite plates with rectangular flaws are computed and discussed in comparison with results for corresponding plates without flaws. A technique for determining the length of a rectangular flaw in a plate is also presented. The results presented in this paper are of importance and could be used in the characterization of flaws in anisotropic laminated plates. 相似文献
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仪器缺少维修及养护直接影响测报工作的完成,以 S L1 型翻斗式遥测雨量计为例,从仪器的结构原理出发,介绍仪器的维修和养护方法,并简单论述仪器维护的重要性,提出一些搞好仪器维护的建议。 相似文献
37.
In this paper we analyze the algebraic formulations of certain geometry statements appearing in recent literature related to mechanical geometry theorem proving and give several examples to show that one of these formulations can cause serious problems. We clarify a formulation which is essentially due to W. T. Wu and, in our opinion, is the most satisfactory.This author was supported by NSF Grants DCR-8503498 and CCR-8702108. 相似文献
38.
通过对防水粉憎水膜形成途径的探索,提出了憎水膜形成过程的基本假设,利用微观测试方法证实了憎水膜层的存在.试验并研究了防水粉长期稳定性的诸多问题。 相似文献
39.
分别以94%品位高钛渣和90%品位高钛渣为原料,采用沸腾氯化工艺制备粗TiCl4,分析了两种品位高钛渣对沸腾氯化工艺的影响。结果表明:94%品位高钛渣由于其活性低而对沸腾氯化工艺的影响较大。 相似文献
40.