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211.
Kurt Jung 《International journal of occupational safety and ergonomics》2013,19(2):108-117
By establishing the internal market, the European Union intended to create an area in which safety and health at work are guaranteed. For this purpose, a series of directives was passed.The EC Directive 89/686/EEC “Approximation of the laws of the Member States relating to personal protective equipment” is of particular interest to the manufacturers of personal protective equipment (PPE). On the European level, harmonized standards, that put these basic health and safety requirements into more concrete terms have to be available. The European Standardizing Committee (CEN) is charged with the elaboration of European standards.A total of 176 standards relating to personal protective equipment have to be setup; 57 of them are available at present. All CEN members are obliged to transpose them without modification into national standards. Formerly existing national standards have to be withdrawn.Existing European standards sometimes show deficiencies regarding the specification of requirements according to Directive 89/686/EEC: the standardization of PPE for special fields of application and insufficient harmonization of provisions for different PPE serving the same protective purpose. Test methods are not always described precisely enough. 相似文献
212.
Debra F. Pflughoeft-Hassett David J. Hassett Kurt E. Eylands Greg F. Weber Cameron E. Martin 《Journal of the Air & Waste Management Association (1995)》2013,63(10):1214-1218
The duct injection retrofit process for flue gas cleanup of sulfur dioxide emissions has been demonstrated at several sites in the United States through a series of U.S. Department of Energy research projects. As a subcontractor on one of the projects, the University of North Dakota Energy & Environmental Research Center performed a comprehensive characterization of four residues from three demonstration sites. The characterization task objective was to facilitate understanding of materials handling and to identify potential disposal and utilization options for these high-volume coal utilization solid residues. Characterization included evaluation of the physical and engineering properties, chemical composition, mineralogy, and leaching potential. Chemical characterization results provided interesting and valuable information from the standpoint of the bulk chemistry and phase assemblages, as well as potential environmental issues associated with the use or disposal of these materials. Results of the chemical and mineralogical characterizations indicate that duct injection residues will be suitable for specific utilization applications and that disposal of these residues should be similar to many conventional coal combustion residues. Significant mineralogical phase changes were noted in long-term leaching experiments. 相似文献
213.
Hansaem Lee Daeju Lee Seongwan Hong Geum Hee Yun Sungpyo Kim Jung Ki Hwang Woojae Lee Zuwhan Yun 《环境科学学报(英文版)》2014,26(6):1289-1293
Anoxic gas recirculation system was applied to control the membrane fouling in pilot-scale 4-stage anoxic membrane bioreactor(MBR). In the anaerobic-anoxic-anoxic-aerobic flow scheme,hydrophilic polytetrafluoroethylene(PTFE) membrane(0.2 μm, 7.2 m2/module) was submerged in the second anoxic zone. During 8 months operation, the average flux of the membrane was 21.3L/(m2·hr). Chemical cleaning of the membrane was conducted only once with sodium hydroxide and sodium hypochlorite. Dissolved oxygen(DO) concentration in the second anoxic zone was maintained with an average of 0.19 ± 0.05 mg/L. Gas chromatography analysis showed that the headspace gas in the second anoxic reactor was mainly consisted of N2(93.0% ± 2.5%), O2(3.8% ± 0.6%), and CO2(3.0% ± 0.5%), where the saturation DO concentration in liquid phase was 1.57 mg/L. Atmospheric O2 content(20.5% ± 0.8%) was significantly reduced in the anoxic gas. The average pH in the reactor was 7.2 ± 0.4. As a result, the recirculation of the anoxic gas was successfully applied to control the membrane fouling in the anoxic MBR. 相似文献
214.
INTRODUCTION: The aim of this study was to examine whether the introduction of an incident reporting scheme with feedback in two industrial plants had an effect on the number of major incidents. METHOD: An intervention design with measurements before the implementation of the incident reporting scheme and two years later was used to examine the relationship between incident rates, safety climate, the willingness to report incidents and perceived management commitment to safety. RESULTS: The results showed that a successful implementation of an incident reporting scheme was followed by a decline in the incidence of major incidents at a Danish metal plant. A key factor in implementing the scheme was top management commitment, which was lacking at another plant, where the implementation of a similar scheme failed. CONCLUSION: Although the study shows some encouraging results concerning the use of incident reporting schemes to prevent occupational accidents, the possibility to draw causal conclusions is limited in the present study, and further studies are needed before the effectiveness of such schemes can be evaluated with certainty. 相似文献
215.
Structural effect of the in situ generated titania on its ability to oxidize and capture the gas-phase elemental mercury 总被引:1,自引:0,他引:1
Structural effect of the in situ generated TiO(2) sorbent particle was examined for its ability to capture elemental mercury under UV irradiation in a simulated combustion flue gas. Titania particles were prepared by thermal gas-phase oxidation of Titanium (IV) isopropoxide (TTIP) using a high temperature electric furnace reactor. The structural characteristics of the in situ generated TiO(2) at various synthesis temperatures were investigated; size distribution and the geometric mean diameter were measured using a scanning mobility particle sizer, while fractal dimension and radius of gyration were evaluated from the transmission electron microscopy images. Results from the Hg(0) capture experiment show that with increasing titania synthesis temperature, the overall aggregate size increases and the morphology becomes more open-structured to gas-phase Hg(0) and UV light, resulting in the improved mercury removal capability. 相似文献
216.
Phosphate removal is important to control eutrophication and an ion exchange process is one of several treatment processes for this purpose. Hydrotalcite compounds (HTALs) are useful as adsorbents for phosphate removal because of their ion exchange properties. In this study, the adsorption properties of a granular synthetic HTAL for phosphate and the method of regeneration of the granular HTAL were examined. The adsorption isotherm of the granular HTAL was approximated by a modified Langmuir type, and the maximum adsorption capacity was 47.3 mg P g(-1), which corresponded to the content of HTAL in the granular one. Phosphate adsorbed on the HTAL was effectively desorbed with alkaline NaCl solutions and the HTAL was regenerated with 25 w/v% MgCl(2) solution. The regenerated HTAL could be reused repeatedly for the phosphate removal. Phosphate in the exhausted desorption solution was recovered as a precipitate of calcium phosphate by addition of CaCl(2), and the residual exhausted desorption solution could be also reused after supplying NaOH. The results suggest the possibility of an effective system for phosphate removal and recovery, which includes the following processes: adsorption, desorption, recovery of phosphate, and regeneration of the HTAL and the desorption solution. 相似文献
217.
218.
Mi-Young Lee Hye-Sung Won Ji Eun Park Jae-Yoon Shim Pil-Ryang Lee Ahm Kim Jung Bok Lee 《黑龙江环境通报》2016,36(5):424-431
219.
Kurt J. Robinson Robert M. Ragan 《Journal of the American Water Resources Association》1993,29(6):1003-1008
ABSTRACT: The reauthorization of the Clean Water Act reemphasizes the need for regional scale monitoring and management of nonpoint pollution loads. The magnitude of the task will require that local governments and their consultants integrate information systems and modeling if they are to manage the massive data sets and conduct the array of simulations that will be needed to support the decision making processes. Interfacing geographic information systems (GIS) and nonpoint pollution modeling is a logical approach. The objective of the present study was to use the 37,000-acre area defined by the Kensington Quadrangle sheet in Montgomery County, Maryland, to show that GIS-supported nonpoint pollution modeling is practical and economically attractive. The purpose of the GIS is to estimate the spatial distribution of nonpoint nitrogen, phosphorous, zinc, lead, BOD, and sediment using a model developed by the Northern Virginia Planning District Commission. The system allows the user to change land uses in subareas to simulate the consequences of additional development or alternate management strategies. The tests show that in-house development of this type of special purpose GIS is a practical alternative to vendor supplied systems and that the required databases can be developed quite reasonably. 相似文献
220.
Chang-Hyeon Kim Kyung-Moon Jung Jung-Soo Kim Jung-Ki Park 《Journal of Polymers and the Environment》2004,12(3):179-187
Modified polycaprolactone was synthesized by melt reaction of PCL and reactive monomers such as glycidyl methacrylate (GMA) and maleic anhydride (MAH) in the presence of benzoyl peroxide in Brabender mixer. MAH showed a different grafting phenomenon compared to GMA. The reaction mechanism was discussed with different reactive monomers. Reactive blends of the PCL-g-GMA and the gelatinized starch with glycerin were prepared and their mechanical properties and biodegradabilities were investigated. Reactive blends of PCL-g-GMA and starch showed well-dispersed starch domain in the matrix and better mechanical strength than the unmodified PCL/starch blend. However, the reaction between PCL-g-GMA and starch induced a crosslinking during the reactive blending and this crosslinking in the blend lowered the biodegradation of the blend during the composting test. The biodegradability was investigated by the weight loss and surface morphology change of the blend in the composting medium. 相似文献