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881.
A long-term pilot-scale H2-based membrane biofilm reactor (MBfR) was tested for removal of nitrate from actual groundwater. A key feature of this second-generation pilot MBfR is that it employed lower cost polyester hollow fibers and still achieved high loading rate. The steady-state maximum nitrate surface loading at which the effluent nitrate and nitrite concentrations were below the Maximum Contaminant Level (MCL) was at least 5.9 g·N·(m2·d)?1, which corresponds to a maximum volumetric loading of at least 7.7 kg·N·(m3·d) ?1. The steady-state maximum nitrate surface area loading was higher than the highest nitrate surface loading reported in the first-generation MBfRs using composite fibers (2.6 g·N·(m2·d)?1). This work also evaluated the H2-utilization efficiency in MBfR. The measured H2 supply rate was only slightly higher than the stoichiometric H2-utilization rate. Thus, H2 utilization was controlled by diffusion and was close to 100% efficiency, as long as biofilm accumulated on the polyester-fiber surface and the fibers had no leaks.  相似文献   
882.
Journal of Polymers and the Environment - Since biodegradable materials are unwittingly mixed with synthetic materials, this work aimed to study the feasibility of reliably identifying some...  相似文献   
883.
The implementation of a successful ergonomic and medical intervention program designed to reduce the number and severity of injuries and illnesses and the associated levels of discomfort in the workplace is presented. Because of the recent activity concerning the on-again-off-again Occupational Safety and Health Administration (OSHA) Ergonomic Program Standard questions have been raised as to the value and effectiveness of an organization’s ergonomics program. In light of these concerns, the immense cost associated with work-related injury and illness, and the related pain and suffering associated with such injuries and illnesses, it is important to present a workable and effective ergonomic and medical intervention program. The results of this applied study demonstrate that through the application of an ergonomic and medical intervention program, workplace-related injuries and illnesses can be reduced or eliminated.  相似文献   
884.
A computerized handheld procedure is presented in this paper. It is intended as a database complementary tool, to enhance prospective risk analysis in the field of occupational health. The Pendragon forms software (version 3.2) has been used to implement acquisition procedures on Personal Digital Assistants (PDAs) and to transfer data to a computer in an MS-Access format. The data acquisition strategy proposed relies on the risk assessment method practiced at the Institute of Occupational Health Sciences (IST). It involves the use of a systematic hazard list and semi-quantitative risk assessment scales. A set of 7 modular forms has been developed to cover the basic need of field audits. Despite the minor drawbacks observed, the results obtained so far show that handhelds are adequate to support field risk assessment and follow-up activities. Further improvements must still be made in order to increase the tool effectiveness and field adequacy.  相似文献   
885.
Abstract

In many studies, ergonomics has been shown to influence human performance. The aim of this paper was to demonstrate imp ortan t ergonomics influences on quality in industrial production, from the perspective of interactions between humans, technology, organization, and work environment. A second aim was to elab orate on the implications of these findings for the development of quality management strategies. This paper shows that ergonomics problems in terms of adverse work environmental conditions, in appropriate design of technology, and an unsuitable org an izatio n are important causes of quality deficiencies. Problem solving aimed at improving ergonomics, quality, and productivity simultaneously is likely to obtain sup po rt from most of the interest parties of the company, and may also enhance participation. Ergonomics has the potential of becoming a driving force for the development of new quality management strategies.  相似文献   
886.
The Urak Lawoi are indigenous fishermen on Thailand’s west coast. The population includes an estimated 400 divers who dive using surface-supplied compressed air. In a cross-sectional survey conducted among the 6 major communities of Urak Lawoi, questionnaire-based interviews were administered to active divers, ex-divers, and families or colleagues of divers who had died in the previous 5 years. Six deaths resulting from diving-related accidents were identified, indicating a diving-related mortality rate of approximately 300 per 100,000 person-years, while in the same 5-year period 11 divers had been disabled owing to diving-related events, indicating a diving-related disabling event rate of approximately 550 per 100,000 person-years. Among 342 active divers interviewed, one third reported having suffered from decompression illness, although based on reported current symptoms over 50% were classified as suffering from recurring non-disabling decompression illness. Physical examination conducted on a subset of 98 active divers revealed the presence of spinal injury (clonus, raised muscle tone, and heightened reflexes) and of joint damage (pain in one or more joint, crepitus, or restricted movement) in 24 and 30% respectively. Improved primary prevention and medical treatment are needed to reduce mortality and morbidity among this population.  相似文献   
887.
The American National Standards Institute (ANSI)/American Petroleum Institute (API) Standard 780 Security Risk Assessment (SRA) Methodology was published in June 2013 as a U. S. standard for security risk assessments on petroleum and petrochemical facilities. The standard represents a model standard for evaluating all security risks of petroleum and petrochemical infrastructure and operations and assists industries in more thoroughly and consistently conducting SRAs. The 2013 Standard is an update from the previous API/NPRA SRA Methodology (2004) and focuses on expanding functional utility without changing the basic methodology.The methodology can be applied to a wide range of assets even beyond the typical operating facilities of the industry. This includes refining and petrochemical manufacturing operations, pipelines, and transportation operations including truck, marine, and rail, as well as worker and executive security, housing compounds, and remote operational sites. The new standard describes the most efficient and thorough approach for assessing security risks widely applicable to the types of facilities operated by the industry and the security issues they face. It is voluntary but has been adopted by the Kingdom of Saudi Arabia Ministry of Interior High Commission for Industrial Security as the mandatory security risk assessment methodology for industrial facilities.This paper examines the key elements of the ANSI/API SRA process and discusses how forward thinking organizations may use risk-based performance metrics to systematically analyze facility security postures and identify appropriately scaled and fiscally responsible countermeasures based on current and projected threats. The AcuTech Consulting Group developed the methodology under contract to the API, and the author was the project manager for the project.  相似文献   
888.
Caribbean urban waterfronts have been extensively modified in recent decades to encourage business (especially through the development of new commercial districts) and tourism (particularly in the form of cruise shipping). This paper draws on three case studies from Jamaica to explore the processes through which waterfronts have been redeveloped and the ways in which these spaces are used. The transformation and ongoing management of these waterfronts involve the negotiation of a complex set of power relationships between stakeholders operating at a variety of scales, including national governments, the private sector, Jamaican citizens and tourists. The position of waterfronts at the junction of the “urban” and the “natural” environments provides a fruitful nexus for examining the intricacies of society–nature relationships, and illustrates the ways in which ideas of modernity, development, identity and exclusion are incorporated into the local environment.  相似文献   
889.

Local authorities in Sweden are responsible for the management of sewage treatment and municipal solid waste. Due to this, they handle large flows and stocks of materials and substances that may be harmful for the environment. However, knowledge about these flows is sometimes deficient. In addition, the capacity to influence the composition of these flows is mainly beyond the jurisdiction of the local authorities. Flow-oriented studies, such as substance flow analysis (SFA), have proven to be a useful tool in order to understand and quantify these flows. Furthermore, SFA is sometimes claimed to be beneficial to the process of decision making, since it generates comprehensive overviews of the substance in focus. However, quantification of stocks and flows of a certain substance does not necessarily provide sufficient information for environmental management on the local level. Hence, for SFA to further contribute to the environmental management process, there is also a need for development in the interpretation of the results. The main objective of this paper is to contribute to the discussion about (1) how to interpret the results from SFA and (2) how the results from an SFA can be used in environmental management by local authorities. A tentative framework for interpretation is discussed in the paper, focusing on five aspects: total material quantities, exposure to humans and the environment, resource economy, function and capacity to influence the substance flows. Furthermore, the paper discusses the suggested framework applied to results of a regional cadmium inventory.  相似文献   
890.
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