排序方式: 共有222条查询结果,搜索用时 15 毫秒
101.
Estimation of annual potential evapotranspiration at regional scale based on the effect of moisture on soil respiration 总被引:1,自引:0,他引:1
Liyin Liang Author Vitae Author Vitae Junmei Sun Author VitaeAuthor Vitae Yuexiu Cao Author Vitae 《Ecological modelling》2010,221(22):2668-2674
Potential evapotranspiration (PET) is an important component of water cycle. For traditional models derived from the principle of aerodynamics and the surface energy balance, its calculation always includes many parameters, such as net radiation, water vapor pressure, air temperature and wind speed. We found that it can be acquired in an easier way in specific regions. In this study, a new PET model (PETP model) derived from two empirical models of soil respiration was evaluated using the Penman-Monteith equation as a standard method. The results indicate that the PETP model estimation concur with the Penman-Monteith equation in sites where annual precipitation ranges from 717.71 mm to 1727.37 mm (R2 = 0.68, p = 0.0002), but show large discrepancies in all sites (R2 = 0.07, p = 0.1280). Then we applied our PETP model at the global scale to the regions with precipitation higher than 700 mm using 2.5° CMAP data to obtain the annual PET for 2006. As expected, the spatial pattern is satisfactory overall, with the highest PET values distributed in the lower latitudes or coastal regions, and with an average of 1292.60 ± 540.15 mm year−1. This PETP model provides a convenient approach to estimate PET at regional scales. 相似文献
102.
103.
104.
Nanotechnology has the potential for the development of new materials and processes that can substitute for toxic materials now used in industry. Excitement over this possibility is tempered, however, by the potential adverse environmental health and safety aspects of the new nanomaterials. Although a few examples from the literature are encouraging, e.g., wire and cable insulation, great care must be taken to perform complete alternatives assessment evaluations of any new nanotechnology-enabled product before its adoption. 相似文献
105.
Marina BeermannAuthor Vitae 《Journal of Cleaner Production》2011,19(8):836-842
Within modern society, business organizations have a co-evolutionary relationship with society and ecosystems. Business organizations face highly diverse risks which they have to recognize, reflect on and handle. Climate change and its impacts clarify the need for managing overall system risk. Research has shown that climate vulnerability of business organizations in the German food industry is characterized by impacts that, in particular, affect business organizations indirectly. Indirect climate change caused impacts are complex, uncertain and characterized by a high degree of unpredictability. They focus on the derived social, ecological, economic and cultural consequences of the direct physical impacts from a worldwide perspective. This paper shows that introducing resilience thinking helps to identify strategic risks and opportunities coping with climate change caused impacts in sense of corporate climate adaptation strategies. Furthermore, it is shown from a strategic management perspective that mitigation is a profound element of long term adaptation strategies. 相似文献
106.
Sari HämäläinenAuthor Vitae Annukka Näyhä Author VitaeHanna-Leena Pesonen Author Vitae 《Journal of Cleaner Production》2011,19(16):1884-1891
Bioenergy and biomass-based products offer the greatest new opportunities for diversifying business in the forest cluster. In particular, biorefineries, which can be integrated into the pulp and paper industry, seem to have immense future potential. This article aims to explore the biorefinery concept and related new products and business operations, as well as new business strategies and company models, which are part of the biorefinery value chain. These factors, which contribute to the establishment and success of forest biorefineries, were examined using internet survey responses and compared between Scandinavia, North America and South America. This article looks at the results of the survey - primarily from the Finnish perspective - to help identify competitive advantages upon which successful business operations in the Finnish forest cluster can be built.According to the survey, the outlooks for technical and raw material choices, as well as barriers to biorefinery diffusion, are very similar in all the studied areas. Biorefineries and related energy products are considered the way to sustainably guarantee the forest cluster’s success. An increase in the price of oil motivates the development of forest biorefineries and wood-based biofuels; however, it is obvious that there is a need to revaluate from a fresh perspective the utilisation of wood and the wood-refining chain in the forest cluster.The survey respondents consider wood-based biofuel and chemical production a serious business opportunity for the forest cluster. In Finland, there is a strong confidence in the production of biofuels. However, all the countries included in the study trust in their own national strengths and in their chance to be a leading actor in the forest biorefinery business worldwide. The forest biorefinery business seems to have market potential, and global competition can thus be expected. 相似文献
107.
Lena StawrebergAuthor Vitae Fredrik WikströmAuthor Vitae 《Journal of Cleaner Production》2011,19(12):1300-1305
Tumble dryers sold on the market today are labelled according to their energy efficiency. This labelling system has primarily two purposes: to guide buyers to a product with low energy use, lower cost and lower environmental impact and to encourage producers to develop even more energy-efficient products. Tumble dryers are optimized for their maximum capacity, which is used as the standard load for determining the energy label. Three different tumble dryers have been tested with different drying loads. Results indicate that all the tested tumble dryers have significantly lower energy efficiency when drying small loads. In order to encourage the development of tumble dryers with high energy efficiency at drying loads used in ordinary households, the standards for the energy labelling system should be revised. 相似文献
108.
Suvi LehtorantaAuthor Vitae Ari NissinenAuthor VitaeTuomas MattilaAuthor Vitae Matti MelanenAuthor Vitae 《Journal of Cleaner Production》2011,19(16):1865-1875
Industrial symbioses (ISs) and eco-industrial parks (EIPs) are key concepts of industrial ecology (IE). The aim of ISs and EIPs is to minimise inefficient material and energy use by utilising local by-product and energy flows. Industrial symbioses tend to develop through spontaneous action of economic actors, for gaining of economic benefit, but these systems can be designed and promoted via policy instruments as well. A literature review showed that national programmes for eco-industrial parks can be found in different parts of the world. In the action programmes and other sustainable consumption and production (SCP) policy documents of the EU, on the other hand, industrial symbioses gain less recognition as a path to enhanced sustainable production. In this article, we consider this and also analyse how the evolution and environmental performance of an industrial symbiosis system centred on a Finnish pulp and paper mill have been affected by SCP policy instruments. With regard to the system forming the subject of the case study, and Finnish industrial systems in general, policy instruments have succeeded in reducing emissions but not in systematically encouraging operators toward symbiosis-like activities. All in all, few studies exist on the overall impact of policy instruments promoting design of eco-industrial parks. It is not self-evident that symbiosis-like production systems would be sustainable in every case, as the background assumptions for political promotion of EIPs suggest. We concluded that industrial symbioses should be analysed and developed on a life cycle basis, with documentation of the real environmental benefits due to efficient resource use and decreased emissions in comparison to standalone production. ISs can then bring eco-competitiveness to companies in relation to SCP tools, such as environmental permits, ecolabels, and future product regulation based on the Ecodesign Directive in Europe. Indirect encouragement of symbiosis through land-use regulation and planning, in such a way that material fluxes between companies are possible both in operations and in financial terms, may prove effective. The same holds for waste policies that encourage increased reuse of a company’s waste by other enterprises. 相似文献
109.
Thomas G. Bobick Author Vitae E.A. McKenzie Jr. Author Vitae Author Vitae 《Journal of Safety Research》2010,41(3):203-211
Introduction
Fall-related occupational injuries and fatalities are serious problems in the U.S. construction industry, especially incidents related to unguarded holes. The National Institute for Occupational Safety and Health, Division of Safety Research, Morgantown, WV conducted a project to evaluate the effectiveness of guardrail systems to prevent falls through roof and floor holes.Methods
Two commercial edge-protection products were evaluated when used as perimeter guarding around a roof hole. Installations of the commercial products were compared to job-built guardrails constructed of 2″ × 4″ construction-grade lumber. Occupational Safety and Health Administration (OSHA) regulations require that “a force of at least 200 pounds” must be supported by the top rail of a guardrail system “in any outward or downward direction at any point along the top edge.” A laboratory testing system was developed to evaluate this requirement. A dynamic 200-lb force was generated against the top rail using a weighted manikin mounted on a hinged steel frame. Nine construction workers, who served as test subjects, each built five different guardrail configurations.Results
All 45 configurations met the 200-lb OSHA requirement. Installation time for one commercial product was 32% quicker than the job-built configuration (25.6 min vs. 37.9 min).Impact on Industry
This study: (a) indicates that the two edge-protection products can be used as perimeter guarding; (b) highlights the importance of using proper materials and fasteners to construct guardrails to protect workers from falling into unguarded roof and floor holes; and (c) discusses an overall-strength-testing methodology that can be used by fall-protection researchers. 相似文献110.