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81.
临近岁末,在江西南昌市昌南工业区发生了一件轰动全城的事情。一个规划占地约500亩,包括板材、型材、金属材料、陶瓷、五金、涂料、石材批发市场和以室内装潢为主的家居广场,经营规模位居华东之首的华东装潢建材博览城项目正式启动。这个项目的规划方案刚刚公布,全市数百家建材  相似文献   
82.
卫百民  刘文胜  吕玉 《山西建筑》2004,30(18):44-45
针对预应力楼板在施工中存在的质量通病,介绍了对预制楼板板缝宽度及找平的控制方法,有效地防止楼板裂缝的产生,提高室内地面、屋顶粉刷的平整度。  相似文献   
83.
Since early 1986, a monitoring program for radionuclides in imported foods has been carried out by the Iraqi Atomic Energy Commission. After the Chernobyl nuclear reactor accident in the Soviet Union, the program was expanded; our laboratory was officially designated by the Iraqi Government to measure radionuclide activity concentrations in foodstuff imported from countries known to be severely contaminated by Chernobyl radioactive fallout. Gamma-spectrometric analysis was used. Food items such as powdered milk, lamb meat, poultry, cereals and grains imported into Iraq before the Chernobyl accident did not contain any detectable fission products. However, all lamb meat, 81% of the lentil, 44% of the powdered milk and chick-pea, and 17% of the roast beef samples were contaminated with 137Cs or 134Cs and 137Cs. The highest 137Cs contamination levels found were 82, 147, 420, 6 and 4 Bq kg-1, respectively. Contamination by 134Cs was approximately 50% of the values given above.  相似文献   
84.

Anniversaries and Memorable Dates

Congratulations to Valerii Viktorovich Mikheev Candidate of Technical Sciences, honorable builder of the Russian Federation, and recipient of the prize awarded by the Council of Ministers of the USSR  相似文献   
85.
Formation of dark patinas on rocky surfaces is mainly related to the deposition of gases and particles and to sulphation mechanisms. In the present study, samples of dark patinas taken from granitic outcrops and from granitic buildings were examined in an attempt to understand the mechanisms of their formation. The outcrops are located in non-polluted areas and are characterized by the absence of any extraneous material that provides calcium, such as e.g. mortar. The buildings are located in areas with low levels of pollution. The climate in the study area favours proliferation of microorganisms. Important differences between the patinas sampled from outcrops and from buildings were observed, as the former are of biological origin and the latter of anthropogenic origin. Although the levels of pollution are low in the sampling area, sulphur was present in all of the samples from urban buildings. Sulphur was not present in patinas from outcrops or in patinas from monuments that are assumed to behave as outcrops (dolmens), although the latter are also of anthropogenic origin. Finally, the patinas were found to be formed by elements accumulated on the surface and not from elements contained within the rock itself.  相似文献   
86.
We have studied the process of a prolonged dynamic filtration on activated carbon in two biosorption systems — without preoxidation treatment of the initial matter and after ozonization. It has been shown that given the uniform load on activated carbon terms of the organic matter the efficiency of the biosorption process after preozonization is 2.3 times as small compared with that that without pretreatment, which correlates with the change of adsorption free energy.  相似文献   
87.
A comparison is made between pre- and post-drainage scheme river flows recorded on the River Maine, Co. Antrim. A method of using five-year reference periods has been applied to the mean daily flows to smooth and eliminate, as far as possible, variations due to climatic changes.
Any loss of energy production which might have been due to changes in river flow was examined for turbine installations at a factory at Cullybackey. The quantities of usable water, and hence potential energy production, were calculated for each of the post-scheme five-year periods and compared with a pre-scheme five-year reference period. Any potential loss was then represented by a depreciation factor. It was found that no measurable loss of potential energy production has occurred on the River Maine in the post-scheme period.  相似文献   
88.
SVM handles classification problem only considering samples themselves and the classification effect depends on the characteristics of the training samples but not the current information of classified problem.From the phenomena of data crossing in systems,this paper improves the classification effect of SVM by adding the prior probability item reflecting the classified problem information into the decision function,which fuses the Bayesian criterion into SVM.The detailed deducing process and realizing steps of the algorithm are put forward.It is verified through two instances.The results showthat the new algorithm has better effect than the traditional SVM algorithm,and its robustness and sensitivity are all improved.  相似文献   
89.
静稳定性是航空深弹稳定飞行的先决条件,某对称配置的航空深弹静稳设计主要通过调整安定器的外形和相对位置实现。利用CFD方法研究某航空深弹在各种安定器外形参数条件下的流体动力参数,优化在总体接口条件限制下最可能实现的安定器外形设计。通过使用Fluent软件计算结果与试验结果的比较,认为此计算结果可信。  相似文献   
90.
照片中镶嵌着丰富的Exif信息,从中可提取出拍摄位置与时间等实用数据服务于我们的工作与生活。本文分析了Exif数据格式,介绍了其读取方法,总结了Exif信息提取算法。结合具体实例,进行测试验证,对日常手机定位精度情况进行了评估。最后,通过生产实践,验证Exif信息对于提高测绘与地理信息单位的作业效率与质量控制的促进作用,同时对应用前景进行了展望。  相似文献   
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