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61.
62.
Conclusions 1. The scheme that we developed is efficient and ensures thawing over a period of 40–45 days.
2. To accelerate thawing by 8–10 days when using two electric heaters in each hole, it is necessary to raise the heaters by
3–4 m after 25 days and continue thawing.
3. An 8–10-day reduction in the thaw time is also possible by using three 1.25-kW electric heaters in each hole in place of
two heaters of the same capacity, installing them at depths of 20, 14, and 8 m from the surface.
Taking the results of the experimental work account, the State Institute for Special Design developed a plan for the production
preconstruction thawing of soils over a area of 12,380 m2.
The volume of soil thawed was 324,400 m3.
Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 3, pp. 7–8. May–June, 1982. 相似文献
63.
V. I. Sheinin V. V. Mikheev N. B. Popov Yu. V. Lesovoi 《Soil Mechanics and Foundation Engineering》1991,28(2):79-83
Conclusions 1. The method proposed for the probabilistic design of beds makes it possible to obtain a well-founded design solution corresponding
to a given reliability level, which, in many cases, is more economic than the solution recommended in the Construction Rules
and Regulations.
2. The design solution adopted as a result of the calculation set forth in the Construction Rules and Regulations possesses
a reliability level, which, for some unknown reason, is on the high side.
Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 2, pp. 18–20, March–April 1991. 相似文献
64.
Williamson BJ Mikhailova I Purvis OW Udachin V 《The Science of the total environment》2004,322(1-3):139-154
Scanning electron microscopy with energy-dispersive X-ray analysis (SEM-EDX) of particulate matter on lichen transplant thalli (Hypogymnia physodes) was assessed as a complementary technique to wet chemical analysis for source apportionment of airborne contaminants. Transplants (2 month exposure) stationed in the Cu smelter and former mining town of Karabash were compared with those from a control site 30 km south. Particulate matter in Karabash samples (715 analyses) showed higher levels of S, Pb, Cu, Sn and Zn compared with the control (598 analyses). Complex element associations among the particles confounded detailed mineralogical identifications, and therefore a simplified particle classification scheme was devised for source apportionment. Karabash samples contained high levels of particles classified as mining-related (MRP), and these were also identified in control samples, indicating wide spatial dispersion from the smelter and highlighting the sensitivity of the method. It was noted that MRP <2.5-microm diameter were poorly represented on lichen surfaces suggesting this may limit the usefulness of Hypogymnia transplants as proxies when assessing human health impacts from airborne particulates. Analyses of the lichen thallus surface (away from surface particulates) revealed high levels of Cu, Zn, Fe and Pb associated with organics in the Karabash samples compared with the control, with a proportionate loss of K, interpreted as being due to a stress-related increase in cell membrane permeability. This type of analysis may provide a novel SEM-EDX-based method for assessing lichen vitality. The techniques developed are presented and further implications of the study are discussed. 相似文献
65.
The history of the development of methodical and regulatory documents relative to construction in karst-prone areas is cited.
The basic content of existing regulatory documents is presented, and attention is focused on some of their deficiencies. Specific
approaches to the development of a standard for construction in karst-prone areas are proposed.
__________
Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 6, pp. 21–24, November–December, 2006. 相似文献
66.
Carmen Vázquez 《Journal of Housing and the Built Environment》1992,7(4):357-376
This article was written as part of a wider research project on Madrid's social geography supported by the Spanish Ministry
of Education and Science (Project PB88/0181). It was initially presented as a paper at the International Research ConferenceEuropean Cities: Growth and Decline The Hague, The Netherlands, 13–16 April 1992. 相似文献
67.
Lewné M Cyrys J Meliefste K Hoek G Brauer M Fischer P Gehring U Heinrich J Brunekreef B Bellander T 《The Science of the total environment》2004,332(1-3):217-230
In order to estimate the spatial variation within well-defined study areas, nitrogen dioxide was measured with diffusion samplers (Palmes tube) in 40-42 sites each in Germany (Munich), the Netherlands and Sweden (Stockholm County). Each site was measured over four 2-week periods during 1 year (spring 1999 to summer 2000). In each country, one reference site was measured during all periods and the results were used to adjust for seasonal variability, to improve the estimates of the annual average. Comparisons between the chemiluminescence method (European reference method) and Palmes tube measurement indicated a good agreement in Germany (with a ratio of 1.0 for Palmes tube/chemiluminescence) but underestimation for Palmes tube measurement in the Netherlands and Sweden (0.8 for both countries). The r2 values were between 0.86 and 0.90 for all three countries. The annual average values for NO2 for different sampling sites were between 15.9 and 50.6 (mean 28.8 microg/m3) in Germany, between 12.1 and 50.8 (mean 28.9 microg/m3) in the Netherlands and between 6.1 and 44.7 (mean 18.5 microg/m3) in Sweden. Comparing spatial variation between similar sites in the three countries, we did not find any significant differences between annual average levels for urban traffic sites. In Sweden, annual average levels in urban background and suburban backgrounds sites were about 8 microg/m3 lower than comparable sites in Germany and the Netherlands. Comparing site types within each country only urban traffic sites and suburban background sites differed in Germany. In the Netherlands and Sweden, the urban traffic sites differed from all other sites and in Sweden also the urban background sites differed from the other background sites. The observed contribution from local traffic was similar in the Netherlands and Sweden (10 and 8 microg/m3, corresponding to 26-27% of the NO2 concentration found in the urban traffic sites). In Germany, the contribution from local traffic was only 3 microg/m3, corresponding to 9% of the NO2 concentration found in the urban traffic sites. The spatial variation was substantially larger for NO2 than the variation for PM2.5 and similar to PM2.5 absorbance, measured in the same locations. 相似文献
68.
N. A. Klimenko L. V. Nevinnaya Yu. V. Sidorenko O. G. Shvidenko Yu. O. Shvadshina 《Journal of Water Chemistry and Technology》2007,29(1):15-22
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
69.
Bulletin of Engineering Geology and the Environment - La fermeture de l'Escaut oriental constitute le couronnement des travaux du Plan Delta aux Pays-Bas. Le danger de l'érosion et de... 相似文献
70.