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191.
Safety at Finnish work places is mainly considered to be the task of a separate safety organization, e.g., a safety manager and safety delegates. However, it is the supervisor who is responsible for the daily safety in the departments. The Finnish paper industry has developed a supplementary system for the safety organization to carry out safety work in the factories. The monitoring and improving of the daily safety has been delegated to small groups in the production departments. These small groups consist of the supervisor and the safety representative (worker member) of the work area. Sometimes also a department manager or a member of the maintenance department may participate in the work group. A training program was designed to give basic knowledge and skills for the groups. The course has helped the participants to better outline their duties and activities within the safety field.  相似文献   
192.
A method using GC-MS and derivatization with N-(t-butyldimethylsilyl)-N-methyltrifluoroacetamide (MTBSTFA) was developed for the analysis of 20 phenolic compounds in atmospheric samples (gas and particles). Air sampling was carried out using a Hi-Vol sampler with glass fibre filter and XAD-2 resin at a flow rate of 60 m(3) h(-1). The particle and gas phases were collected separately over a period of 4 h. Samples were Soxhlet extracted, evaporated to dryness under nitrogen and refilled with acetonitrile. 100 microl of these extracts were derivatized with 100 microl of MTBSTFA at 80 degrees C for 1 h under strong stirring. Phenolic compounds were injected into a GC-MS in splitless mode and quantified as their TBDMS derivatives in the SIM mode. Mass spectral analysis of the derivatives of the 20 compounds studied indicates that the spectra are highly specific showing an ion at [M - 57]+ which is useful for structure confirmation or analysis at low levels using selected ion monitoring. Quantification limits varied between 5 microg l(-1) and 10 microg l(-1) which correspond to 20 pg m(-3) and 40 pg m(-3) for 250 m(3) of air sampled. This method was successfully applied to atmospheric samples.  相似文献   
193.
Passive samplers were used to monitor ammonia concentrations at rural inner alpine and pre-alpine, as well as urban, sites in Austria and Bavaria. Elevated concentrations were measured both at farms (up to 36 microg NH3 m(-3)) and at urban locations (up to 28 microg NH3 m(-3)). At urban locations a linear relationship between the traffic density and the NH3 concentration was found, but there was no marked seasonal trend. The highest ammonia concentrations were measured in a traffic tunnel (up to 78 microg NH3 m(-3)). The presence of livestock breeding or small scale alpine pastures resulted in elevated concentrations at the rural sites (8.1-12 and 2.5-4.6 microg NH3 m(-3), respectively), compared to the surrounding areas (3.1 and 0.9 microg NH3 m(-3)). Agriculture related sources are usually limited either spatially or seasonally. As the emissions were moderate in our case, a rapid removal and dilution of ammonia was possible and therefore the NH3 burden was only local. Sources related to traffic are more evenly distributed both geographically and seasonally. The WHO guideline, annual average concentration of 8 microg m(-3) for the protection of vegetation, was only exceeded at farms, at the urban station with the heaviest traffic and in the Tauerntunnel.  相似文献   
194.
The influence of oxidation and ripening on the kinetics of heavy metal release from anoxic sediments was investigated by means of porewater analysis and pH(stat) leaching tests. During simulated land disposal of an anoxic river sediment, a considerable heavy metal (Cd, Zn and Ni) release into the porewater was observed after 25 days of exposure of the sediment to the air. The release kinetics of Cd and Zn during pH(stat) leaching indicated that their release was related to the oxidation of Cd- and Zn-sulfides. It was not completely clear whether the release of Ni was due to the oxidation of Ni-sulfides or to the introduction of H(+)(generated by the oxidation of sulfides or introduced by titration). The release of Cu seemed to be explained by the oxidation of both Fe-sulfides and Cu-sulfides. As such, pH(stat) experiments provided an indirect way to assess the mineralogy of the anoxic sediment. During ripening of the sediment, the release rate of Zn and Cd in pH(stat) leaching tests increased. For Ni, however, a similar release pattern was observed in the anoxic sediment and in the ripened sediments. Two weeks' drying at 100 degrees C resulted in an increase in the leachability of Cu. Nevertheless, at pH 4 and 6, the thermally treated sediment displayed a slower leaching of Cd and Zn than the ripened sediment. Although thermal treatment is often used to simulate ageing in soils, it cannot be used to simulate ripening of anoxic sediments.  相似文献   
195.
The lakes in KillarneyProvincial Park, located 40–60 km southwest ofSudbury, Ontario, were some of the first lakesin North America to be acidified by atmosphericpollutants. Acidification affected thousandsof fish and invertebrate populations in dozensof lakes. Since the 1970's, water quality hasimproved in response to atmospheric pollutionreductions and some lakes have alreadyrecovered to approximately their pre-industrialpH levels, as inferred from diatom microfossilsin lake sediments. Since the 1970's, fishspecies richness has not changed substantially,but zooplankton species richness has increasedin acidified lakes. The critical sulphur load,the amount of SO2-derived acid depositionthat can occur while still maintaining suitable water quality, was estimated to beexceeded in 38% of the park area in 1997. Depending on which of four possible NorthAmerican emission control scenarios (CLR =currently legislated reduction; CLR + 25%; CLR+ 50%; CLR + 75%) is achieved by 2010, theprojected critical loads will be exceeded inabout 0-30% of the park area in the future. There are many factors that can affectbiological recovery rates of damaged lakes, butit is expected that biological recovery willlag considerably behind observed chemicalrecovery rates.  相似文献   
196.
This article details the results of an investigation into the application of geostatistical data analysis to two environmentalradiometric time series. The data series employed consist of 99Tc values for seaweed (Fucus vesiculosus) and seawater samples taken as part of a marine monitoring program conducted on the coast of northern Norway by the Norwegian Radiation Protection Authority. Geostatistical methods were selected in order to provide information on values of the variables at unsampled times and to investigate the temporalcorrelation exhibited by the data sets. This information is ofuse in the optimisation of future sampling schemes and for providing information on the temporal behaviour of the variablesin question that may not be obtained during a cursory analysis.The results indicate a high degree of temporal correlation withinthe data sets, the correlation for the seawater and seaweed databeing modelled with an exponential and linear function,respectively. The semi-variogram for the seawater data indicatesa temporal range of correlation of approximately 395 days with noapparent random component to the overall variance structure and was described best by an exponential function. The temporal structure of the seaweed data was best modelled by a linear function with a small nugget component. Evidence of drift was present in both semi-variograms. Interpolation of the data setsusing the fitted models and a simple kriging procedure were compared, using a cross-validation procedure, with simple linearinterpolation. Results of this exercise indicate that, for theseawater data, the kriging procedure outperformed the simpleinterpolation with respect to error distribution andcorrelation of estimates with actual values. Using theunbounded linear model with the seaweed data produced estimatesthat were only marginally better than those produced by thesimple interpolation.  相似文献   
197.
Two spectrophotometric assays for protein commonly used in marine research (Coomassie stain, Bradford; alkaline copper, Lowry) and a more recent assay which has not been applied in this field (bicinchoninic acid, Smith) were compared for homogenates of the marine diatom Thalassiosira pseudonona using bovine serum albumin (BSA) as a standard. When homogenates were prepared by precipitating protein with trichloroacetic acid (TCA) and redissolving in 1 N NaOH, the protein content estimated by the Lowry and Smith assays agreed closely, but was consistently 20% higher than that indicated by the Bradford assay. To determine if this difference was due to the choice of a protein standard, protein from T. pseudonana was purified and compared to BSA, bovine gamma-globulin (BGG), and casein. The reactivity of the purified protein (expressed as the slope of the absorbance vs protein concentration curve) did not differ between cultures grown at high or low irradiance. For the Smith and Bradford assays the reactivity of BSA was not significantly different from algal protein, but for the Lowry assay, algal protein was significantly higher in reactivity than BSA. BGG was not significantly different in reactivity from algal protein for the Lowry and Smith assays, but BGG gave significantly lower absorbances than algal protein in the Bradford assay. These results suggest that BSA is a suitable standard for algal protein in the Bradford assays, while BGG is preferable for the Lowry assay. Either protein standard could be used for the Smith assay. Differences in purified algal protein reactivity compared to BSA could not account for the differences among the assays, nor could interference by chlorophyll a. Precipitating protein with TCA prior to analyses gave lower protein than direct analyses of homogenates for the Lowry and Smith assays, but no differences were found for the Bradford assay. As a result, the Lowry and Smith assays indicated up to 60% greater protein than the Bradford if TCA precipitation was not performed. This may be due to removal of free amino acids and small peptides which are less reactive in the Bradford assay. The 20% higher protein found in the Lowry or Smith vs Bradford assays may be due to different assay sensitivity to small peptides or other compounds which are precipitated along with proteins by TCA. Although the Smith assay is substantially simpler to perform than the Lowry, there appear to be no quantitative differences in the results. It remains unclear which spectrophotometric assay is most accurate, but the Bradford assay is faster and simpler, and is less likely to be affected by non-protein compounds found in marine phytoplankton.  相似文献   
198.
Transmitted light measurements performed with a UV-visible spectrophotometer were used to characterize how starch affects the position of boundaries on the phase diagram for dilute aqueous solutions of levan (a branched polymer of fructose). Data were collected in the range 15 to 70°C; the minimum concentrations required for separation of a nematic phase and the minimum concentration required for a fully nematic solution were identified within this range. While hard interactions (repulsion between rod-like molecular segments) dictate the formation of a liquid crystalline phase at and above ambient temperature in the absence of starch, soft interactions become more significant as solutions are cooled toward ambient when starch is present. Small amounts of starch might be used as a filler to modify the mechanical properties (while retaining the process-related benefits) of levan films cast from liquid crystalline solution.  相似文献   
199.
Five studies of the background level of several perfluorocarbon compounds in Europe are here presented together with measurements from the European Tracer Experiment (ETEX). The tracers used during the two ETEX tracer releases were the perfluorocarbons (PFCs); perfluoromethylcyclohexane (C7F14, PMCH) and perfluoromethylcyclopentane (C6F12, PMCP). Their background concentrations were detected by using both passive and active sampling techniques, to define the spatial and temporal variation of the PFCs over Europe. Also the background variations of four isomers of the PFC compound perfluorodimethylcyclohexane (C8F16, PDCH) were studied. The results were compared to other PFC tracer studies in the U.S.A. and Europe. The mean and median values of the measured PFCs were found to vary slightly and randomly in space and time. They were found to be higher and to have a larger standard deviation than the measurements from the American studies. The background concentrations were still found to be low and stable enough for PFCs to be highly suitable for use in tracer studies. The following concentrations were found: PMCP; 4.6±0.3 fl ℓ-1, PMCH: 4.6±0.8 fl ℓ-1, ocPDCH: 0.96±0.33 fl ℓ-1, mtPDCH: 9.3±0.8 fl ℓ-1, mcPDCH: 8.8±0.8 fl ℓ-1, ptPDCH: 6.1±0.8 fl ℓ-1. A study of the correlation between the measured PFC compounds showed a significant correlation between most of the compounds, which indicate that there are no major PFC sources in Europe.  相似文献   
200.
This research explored ironic evaluation processes initiated by suppression instructions conveyed during diversity training. Raters watched one of three training videos: a video providing information about age diversity and recommending that they try to suppress age‐related thoughts; a video providing information about age, sex, race, and ethnic diversity and recommending that they try to suppress demography‐related thoughts; or a control video containing no suppression recommendations. All raters then evaluated a series of job applicants. During the evaluation task, some raters were cognitively busy while others were not. Ironically, busy raters instructed to suppress age‐related thoughts evaluated an older applicant less favorably than raters in other conditions. These results suggest that organizational diversity training including instructions to suppress stereotypic thoughts may have detrimental effects on evaluations of non‐traditional job applicants if raters are cognitively busy when they implement these instructions. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
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