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971.
T. Gallé 《Environmental Sciences Europe》2010,22(6):656-660
The Water Framework Directive’s (WFD) choice of good ecological status as a metric of the immission situation in water bodies implicitly considers the exposure of biota to pollutants. However, the exposure concept lacks consequent links to food webs and substance cycles where sediments and suspended matter play an important role. This is traceable in monitoring as well as in evaluation schemes. This article identifies the major challenges towards a process-oriented approach. 相似文献
972.
Effects of atrazine and nicosulfuron on freshwater microalgae 总被引:2,自引:0,他引:2
Growth modifications caused by various concentrations of atrazine and nicosulfuron were monitored in closed and continuous culture of Chlorella vulgaris (chlorophyta), Navicula accommoda (diatomophyta), and Oscillatoria limnetica (cyanophyta). The concentration at which algal growth rate was reduced twofold (EC50) was determined in the three species for both herbicides. Comparatively, the two toxicants were applied at 10 microg/l level in microcosms inoculated with natural phytoplankton from Lake Geneva. The relative abundances of major phytoplanktonic species were measured by algal cell count at the beginning and at the end of each experiment. Atrazine and nicosulfuron have different targets in plant metabolism, respectively, photosystem II (PSII) and acetolactate synthase (ALS), and the expected effects were different. Generally, the cultured phytoplankton exhibited various sensitivities, depending on species or herbicide. In the microcosms, the major taxa of natural phytoplanktonic samples exhibited various patterns, from acute toxicity to growth enhancement. For example, the diatoms inside the community were not affected by atrazine and nicosulfuron, except for Stephanodiscus minutulus that was sensitive to both, and Asterionella/formosa that was sensitive only to nicosulfuron. The specific physiology and the relationships among the phytoplanktonic communities have to be carefully considered when one would try to predict the extent of herbicide action on natural phytoplankton using in vitro tests. There is a need to test the toxic effect on various cultured strains, representative of most of the taxonomic composition of natural communities, to take into account the wide range of sensitivities and reaction to herbicide contamination. But this is not enough to give a solid frame when transposing the results to the field, and the use of more ecologically relevant systems is recommended. 相似文献
973.
Magnago Rachel Faverzani de Alcântara Braglia Thiago de Aguiar Ana Carolina Baungarten Polyana Mendonça Bruno Afonso Büchele Silva Heloisa Regina Turatti Egert Paola Girotto Edivandro Júnior Américo Cruz Parma Gabriel Oscar Cremona 《Journal of Material Cycles and Waste Management》2021,23(3):1126-1140
Journal of Material Cycles and Waste Management - This article aims to study the mechanical strength and fire resistance of polyurethane/cement (PuCem) composites containing glass sludge and sludge... 相似文献
974.
Kormaňáková Marcela Remešová Marcela Vančová Terézia 《Journal of Material Cycles and Waste Management》2021,23(4):1348-1364
Journal of Material Cycles and Waste Management - The problem of food waste is broadly discussed, but empirical data are still missing. The importance of this topic increases as the reporting of... 相似文献
975.
Juhani Smolander Kalev Kuklane Désirée Gavhed Håkan Nilsson 《International journal of occupational safety and ergonomics》2013,19(2):111-117
The aim of the study was to examine the effects of wearing an ice-vest (ca 1 kg) on physiological and subjective responses in fire fighters. The experiments were carried out on a treadmill in a hot-dry environment. The physical cooling effect of the ice-vest was measured with a thermal manikin. The ice-vest effectively reduced skin temperatures under the vest. On average, heart rate was 10 beats/min lower, the amount of sweating was reduced by 13%, and subjective sensations of effort and warmth were lower during work with the ice-vest compared to work without it. Thermal manikin tests indicated that the useful energy available from the vest for body cooling was rather high (58%). In conclusion, the ice-vest reduces physiological and subjective strain responses during heavy work in the heat, and may promote efficient work time by 10%. 相似文献
976.
Lina Giedraityte Ingvar Holmér 《International journal of occupational safety and ergonomics》2013,19(2):135-148
The aim of this study was to validate the Edholm scale (Edholm, 1966) and the ISO 8996 standard (International Organization for Standardization [ISO], 1990) by comparing the metabolic rates estimated for both methods with the actual measured metabolic rate (MMeas) in 6 manual material handling tasks simulated under laboratory conditions. The metabolic rate was calculated from oxygen consumption VO2 (19 participants) according to Standard No. ISO 8996 (ISO, 1990). Additionally, the participants estimated perceived exertion using the Borg scale. The metabolic rates derived from the Edholm scale (MEdh) overestimated 5 of 6 activities by 34-50% (α = .05). The metabolic rates derived from ISO 8996 (MISO) overestimated all activities by 7-38% (α =.05). 相似文献
977.
Kalev Kuklane Rallema Afanasieva Olga Burmistrova Nina Bessonova Ingvar Holmér 《International journal of occupational safety and ergonomics》2013,19(4):465-476
This study compared the methods of determining footwear insulation on human participants and a thermal foot model. Another purpose was to find the minimal number of measurement points on the human foot that is needed for insulation calculation. A bare foot was tested at 3 ambient temperatures on 6 participants. Three types of footwear were tested on 2 participants. The mean insulation for a bare foot obtained on the participant and model were similar. The insulation of warm footwear measured by the 2 methods was also similar. For thin footwear the insulation values from the participants were higher than those from the thermal model. The differences could be related to undefined physiological factors. Two points on the foot can be enough to measure the insulation of footwear on human participants (r = .98). However, due to the big individual differences of humans, and good repeatability and simplicity of thermal foot method, the latter should be preferred for testing. 相似文献
978.
Kalev Kuklane Ingvar Holmér Rallema Afanasieva 《International journal of occupational safety and ergonomics》2013,19(4):477-484
The present European Standard for footwear testing (Standard No. EN 344:1992; European Committee for Standardization [CEN], 1992) classifies footwear thermally by a temperature drop inside the footwear during 30 min at defined conditions. Today, other methods for footwear thermal testing are also available. The aim of this study was to compare EN 344:1992 with a thermal foot method. Six boots were tested according to both methods. Additional tests with modified standard tests were also carried out. The methods ranked the footwear in a similar way. However, the test according to standard EN 344:1992 is a pass-or-fail test, whereas data that is gained from the thermal foot method gives more information and allows further use in research and product development. A change of the present standard method is suggested. 相似文献
979.
Kalev Kuklane Ingvar Holmér 《International journal of occupational safety and ergonomics》2013,19(2):123-136
The study aimed to find out the influence of sweating on footwear insulation with a thermal foot model. Simultaneously, the influence of applied weight (35 kg), sock, and steel toe cap were studied. Water to 3 sweat glands was supplied with a pump at the rate of 10 g/hr in total. Four models of boots with steel toe caps were tested. The same models were manufactured also without steel toe. Sweating reduced footwear insulation 19–25% (30–37% in toes). During static conditions, only a minimal amount of sweat evaporated from boots. Weight affected sole insulation: Reduction depended on compressibility of sole material. The influence of steel toe varied with insulation. The method of thermal foot model appears to be a practical tool for footwear evaluation. 相似文献
980.
Antioco López-Molina Richart Vázquez-Román M. Sam Mannan M. Guadalupe Félix-Flores 《Journal of Loss Prevention in the Process Industries》2013,26(5):887-894
An approach to reduce the probability of producing a domino effect in process industry is developed in this work. It is assumed that optimal layouts should include appropriate analysis to reduce risk during the process design stage. The model developed for this approach combines the estimation of probability of damage due to overpressure, proposed by Mingguang and Juncheng (2008), and escalation threshold values defined by Cozzani, Gubinelli, and Salzano (2006). These equations are combined with other typical layout constraints as well as bounding the probability constraint, which has resulted in a highly non-linear MINLP problem. Solving a case study used by other authors provides evidence for reliability of the developed approach. In this way, layouts are designed to reduce the escalation probability yielding safe distributions. 相似文献