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91.
I. A. Mednikov Yu. A. Molchanov L. V. Gorodetskii 《Soil Mechanics and Foundation Engineering》1974,11(5):306-310
Conclusions 1. For anlaysis of circular (polygona) slabs which can be included in the category of absolutely rigid slabs, a practical approximate method of analysis has been developed and experimentally verified which permits determining the bending moments under centrally and eccentrically applied loads acting over a small circular area, as well as at any other points in the slab beyond the limits of the loaded area.2. Monolithic bonding of hexagonal road slabs up to 3–4 m2 in area designed for the N-30 load results in increased design bending moments and, consequently, in thicker pavements. For these slabs it is expedient to use nonrigid joints, which do not transmit bending or torsional moments; however, these slabs must be placed on stabilized beds and their joints must be filled with waterproofing mastic.Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 5, pp. 19–22, September–October, 1974. 相似文献
92.
This paper presents the development of a comfort index that measures adaptivity in outdoor spaces. Over a 9-month period 649 people were surveyed in three locations, in temperatures between 10 and 28 °C. An exploratory factor analysis develops a 15-item scale of comfort that includes measures of adaptivity: clothing, exposure time and seating location. The scale is regressed on physical measures: average instantaneous wind speed; maximum wind speed; mean-exposed radiant temperature; mean-shaded radiant temperature and ambient temperature. The results model the relative contributions of the microclimatic factors for the comfort in the outdoor space. Analyses suggest gustiness and wind speed are most important in determining user satisfaction. There is strong support for the theory that people actively adapt to microclimatic conditions. 相似文献
93.
The degree of biodegradability of three non-ionic surfactants has been assessed using small-scale activated-sludge sewage treatment plants. The effect of temperature on biodegradability was studied by operation at 15°, 11° and 8°C.The two alcohol ethoxylate surfactants tested were well degraded at all three operating temperatures. The alkyl phenol ethoxylate surfactant tested was well degraded at 15°C but at lower temperatures the biodegradability was dependent on concentration. At 5 mg 1−1, greater than 90 per cent removal was achieved but at 20 mg 1−1 the degree of removal fluctuated between 40 and 95 per cent at 11°C and between 20 and 80 per cent at 8°C.The present results have been compared with those obtained using the same surfactants in community trials at a small sewage works employing biological filtration. Although a similar temperature effect was observed with the alkyl phenol ethoxylate, the biodegradabilities obtained in the laboratory were consistently greater than those obtained at the sewage works, perhaps because of the constant conditions of the laboratory test. 相似文献
94.
Paleonutritional analysis of the pre-Hispanic population from Fuerteventura (Canary Islands) 总被引:2,自引:0,他引:2
González-Reimer E Velasco-Vázquez J Arnay-de-la-Rosa M Santolaria-Fernández F Galindo-Martín L 《The Science of the total environment》2001,264(3):215-220
In this study, from histological and chemical perspectives, we analyse the human remains belonging to the pre-Hispanic inhabitants from Fuerteventura (one of the Canary Islands) and compare the results with those obtained on a sample of pre-Hispanic inhabitants from Gran Canaria (Canary Islands). We observe that trabecular bone mass was normal in the samples from Fuerteventura except for an elderly woman; this result is in sharp contrast with the decreased bone mass observed in the population from Gran Canaria. The pre-Hispanic population from Fuerteventura showed lower bone strontium, Sr/Ca ratio, and bone barium, but slightly higher bone copper, than that from Gran Canaria. All these data indicate a greater consumption of marine products by the population of Fuerteventura. The high prevalence of osteoporosis observed in the population from Gran Canaria may be interpreted as a consequence of protein-calorie malnutrition, a condition which seemed to be not so prevalent in the population of Fuerteventura. 相似文献
95.
Interstitial P levels in Lake Mendota and Lake Wingra were evaluated as a function of season and water column and sediment depth. Interstitial water was obtained by the centrifugation-filtration method. Temporal variations were observed over the entire 15 cm sediment depth interval examined in all four locations evaluated. Interstitial reactive P (IRP) levels in Lake Mendota ranged from 0.014–1.67 mg l−1 at the 5–6 m water column depth and from 1.20–5.75 mg l−1 at the 18–19.5 m depth. IRP levels in Lake Wingra ranged from 0.029–2.15 mg l−1 at 3.5 m and from 0.191–3.96 mg l−1 at 2 m. Variations in interstitial P were attributed to variations in oxidation state of Fe as influenced by oxygen transport and reduction rates. 相似文献
96.
97.
The paper outlines some of the actions taken by Severn Trent Water to achieve compliance with consent limits since the implementation of the Control of Pollution Act (Part II) in 1985.
Prior to and since 1985, Severn Trent Water has undertaken an extensive programme to analyse the reasons for failure and carry out remedial work. A major feature of this programme, which has been further stimulated by privatization, has been the need to reduce the lead time for carrying out improvements.
The paper discusses the means by which this has been achieved, including the introduction of the 'fast-track'initiative and the 'process matrix'.
Other aspects are outlined including initiatives to develop more robust processes, computerized work scheduling, extensive training programmes and best practice studies. 相似文献
Prior to and since 1985, Severn Trent Water has undertaken an extensive programme to analyse the reasons for failure and carry out remedial work. A major feature of this programme, which has been further stimulated by privatization, has been the need to reduce the lead time for carrying out improvements.
The paper discusses the means by which this has been achieved, including the introduction of the 'fast-track'initiative and the 'process matrix'.
Other aspects are outlined including initiatives to develop more robust processes, computerized work scheduling, extensive training programmes and best practice studies. 相似文献
98.
E.P. Koster B.C.J. Zoeteman G.J. Piet E. De Greef H. Van Oers B.G. Van Der Heijden A.J. Van Der Veer 《The Science of the total environment》1981
The human senses play an important role in assessing the quality of food and of the environment. Particularly the chemical senses of taste and smell determine the pleasantness of foods and drinks and may provide a warning mechanism for the presence of more or less toxic contaminants. Even after the recent rapid development of powerful analytical techniques the human nose can easily detect trace amounts of chemicals at levels manytimes lower than the analytical detection limits.Although taste and odour assessment of drinking water has been practized inmany waterworks laboratories by small panels, relatively unreliable results were obtained and such sensory data played up till now only a minor role in the management of the water treatment plant. More sophisticated and reliable methods for sensory water quality evaluation are discussed. Special attention is given to the characteristics of the human senses of taste and smell, to which the methodology of sensory assessment should be better adapted. High numbers of observations on a sample are generally needed, for which purpose the use of large panels has to be realized. In this respect the help of large consumer panels is an alternative for the presently often used small laboratory groups. As an example the preliminary results of a large ongoing experiment of sensory water quality assessment by 2 consumer panels of 100 persons each in the Rotterdam area are discussed. Drinking water quality is judged at the consumer homes every week. The experiment started September 1979 and will be continued for one year. 相似文献
99.
Philip J. Bourque Dominique Gambier Raymond J. Burby III Jack E. Adams Jeffrey B. Nugent D. van der Werf William J. Serow Edward L. Prill Willard Tim Chow R. J. Johnston Craig Zumbrunnen Kingsley E. Haynes Nolin Masih Robert Hines Wilson Philip S. Morrison Debnath Mookherjee Robin Flowerdew Noel D. Uri Panayotis H. Mavrakis Leo E. Zonn Joseph A. Ziegler J. S. L. McCombie Ronald A. Oliveira Jacob J. van Duijn Douglas M. Brown Robert G. Fletcher Lawrence Hugg W. T. Trulove Alene Anderson Bruce Domazllcky 《The Annals of Regional Science》1978,12(1):105-164
100.
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