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排序方式: 共有119条查询结果,搜索用时 795 毫秒
51.
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
52.
R. Herrmann R. Stottlemyer J. C. Zak R. L. Edmonds H. Van Miegroet 《Journal of the American Water Resources Association》2000,36(2):337-346
ABSTRACT: Federal parks and other public lands have unique mandates and rules regulating their use and conservation. Because of variation in their response to local, regional, and global‐scale disturbance, development of mitigation strategies requires substantial research in the context of long‐term inventory and monitoring. In 1982, the National Park Service began long‐term, watershed‐level studies in a series of national parks. The objective was to provide a more comprehensive database against which the effects of global change and other issues could be quantified. A subset of five sites in North Carolina, Texas, Washington, Michigan, and Alaska, is examined here. During the last 50 years, temperatures have declined at the southern sites and increased at the northern sites with the greatest increase in Alaska. Only the most southern site has shown an increase in precipitation amount. The net effect of these trends, especially for the most northern and southern sites, would likely be an increase in the growing season and especially the time soil processes could continue without moisture or temperature limitations. During the last 18 years, there were few trends in atmospheric ion inputs. The most evident was the decline in SO42 deposition. There were no significant relationships between ion input and stream water output. This finding suggests other factors as modification of precipitation or canopy throughfall by soil processes, hydrologic flow path, and snowmelt rates are major processes regulating stream water chemical outputs. 相似文献
53.
浅谈环境监测业务管理的规范化 总被引:1,自引:0,他引:1
黄卫 《环境监测管理与技术》2008,20(1):51-53
简述了环境监测业务的分类,提出应对监测工作流程、监测标准、业务分包工作、监测收费、监测报告格式、监测数据、监测质量、业务项目实行规范化管理。指出,对各类环境监测业务进行规范化管理,将有助于提高环境监测为环境管理和经济建设服务的质量和效率。 相似文献
54.
55.
This study provides the first evidence for the direct biodegradation of persistent organic matter extracted from the organic-rich polymetallic black shale ore Kupferschiefer, one of the most important sources of metals in the world. It was demonstrated that an enriched community of indigenous heterotrophic microorganisms isolated from black shale grown under aerobic conditions could utilize shale organic matter as the sole carbon and energy source. Colonization of shale organic matter was observed. The main biodegradation intermediates and products such as phosphonic acid dioctadecyl ester and isoindole-1,3 were detected in the aqueous phase of cultures. The bacterial community showed the ability to PAH biodegradation, assimilation of organic acids and esters as well as lipase activity. The intracellular accumulation of phosphorus by bacteria during growth on organic matter was confirmed. Strains within the genus Pseudomonas were found to dominate the bacterial population at the end of the experiment. The results of this study confirm that indigenous bacteria are likely to play a role in the biotransformation of black shale and can influence the geochemical cycles of ancient organic carbon in the deep terrestrial subsurface. This process may also occur in tailings ponds containing black shale, and cause the mobilization of potentially toxic compounds to the soil and groundwater. 相似文献
56.
Olof Regnell Mark Elert Lars Olof Höglund Anna Helena Falk Anders Svensson 《Ambio》2014,43(7):878-890
Methylation of mercury (Hg) to highly toxic methyl Hg (MeHg), a process known to occur when organic matter (OM) decomposition leads to anoxia, is considered a worldwide threat to aquatic ecosystems and human health. We measured temporal and spatial variations in sediment MeHg, total Hg (THg), and major elements in a freshwater lagoon in Sweden polluted with Hg-laden cellulose fibers. Fiber decomposition, confined to a narrow surface layer, resulted in loss of carbon (C), uptake of nitrogen (N), phosphorus (P), and sulfur (S), and increased MeHg levels. Notably, fiber decomposition and subsequent erosion of fiber residues will cause buried contaminants to gradually come closer to the sediment–water interface. At an adjacent site where decomposed fiber accumulated, there was a gain in C and a loss of S when MeHg increased. As evidenced by correlation patterns and vertical chemical profiles, reduced S may have fueled C-fixation and Hg methylation at this site. 相似文献
57.
58.
企业电子商务风险的危害及控制 总被引:6,自引:0,他引:6
傅少川 《中国安全科学学报》2003,13(7):55-59
利用电子商务 ,企业能获得响应市场的灵活性 ,及时把握商机。但在提高和巩固企业竞争优势的同时 ,电子商务也给企业带来新的风险。这些问题解决不当 ,将给企业带来灾难性的后果 ,因而引起企业商务决策人的广泛关注。笔者论述了企业电子商务的物理风险、逻辑风险、技术风险、管理风险、企业与企业关系风险 ;电子商务中的财务、税收、金融风险 ,以及外部环境风险 ;分析了各种风险的原因 ;指出了可能对企业造成危害的严重性 ;其次论述了电子商务风险控制及防范 ,从国家层面和行业层面的电子商务风险控制 ,到企业层面的电子商务风险控制 ;充分利用有关技术系统设计控制、电子商务数据加密、电子商务数据完整性保护来回避风险 ;给出了避免和控制这些风险的具体方法 相似文献
59.
Patterns of seasonal and long-term dynamics of the size and structure of the bank vole population were studied in the European
subtaiga subzone, the optimum of the species range. The dynamics of this population proved to undergo complex fluctuations
with cyclic components, which have periods of one year and about three years. The one-year fluctuations of the population
size and structure are accounted for by animal adaptation to seasonal changes in environmental factors. The fluctuations with
the three-year quasi-period are determined by intrapopulation density-dependent mechanisms. 相似文献
60.
Metal price fluctuations have recently been of interest not only because of their cyclical volatility but also of their interaction with business cycles. A related issue is whether metal prices move together sufficiently to collectively reflect macroeconomic influences. Correlation or the tendency for prices to move together has been termed “comovement”, where the commonality in prices reflects the tendency of commodity markets to respond to common business cycle and trend factors. Metal prices are known to respond to macroeconomic influences and the latter might well explain the common factor which causes them to move together. Our goal is to provide an estimate of the common factor in metal prices and to relate this factor to important macroeconomic influences. The prices we study are for aluminum, copper, tin, lead and zinc; the macroeconomic variables include industrial production, consumer prices, interest rates, stock prices, and exchange rates. Our results confirm that the common factor in metal prices can be related to such macroeconomic influences. 相似文献