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481.
The broad objective of this special issue of Mitigation and Adaptation Strategies for Global Change is to address some of the gaps in our knowledge and understanding of the policies, programs, and measures that might be applied to natural hazards and their impacts in an era of climate change. Given the global impacts of climate change and world-wide pattern of increasing losses from natural hazards we necessarily adopt an international perspective. The specific goals of the special issue are to: (a) encompass experiential aspects, emphasizing current practice of mitigation and its associated measures, and their results; and (b) explore primary or root causes of alarming shifts in human and economic costs of environmental extremes. Special emphasis is placed on how human activities are playing a key role in enhancing vulnerability to NTEE (nature-triggered environmental extremes), quite independently from the anthropogenic causes of climate change. The goals are also (c) to examine costs, risks, and benefits (of all kinds including social, political, ecological) of mitigation, and adjustment and adaptation measures; and (d) analyze policy implications of alternative measures. These components are expected to make significant contributions to policy considerations – formulation, implementation and evaluation. There is much uncertainty about the rate of climate change; however, the fact of increase of the atmospheric temperature in the last century is no longer a subject of scientific or policy debate. Due to such changes in the geophysical parameters, certain types of nature-triggered environmental extreme events are likely to continue to increase. How global warming will affect regional climates and pertinent variables is not well known, limiting our ability to predict consequential effects. This factor poses serious constraints against any straightforward policy decisions. Research findings of the work of this volume reaffirm that human dimensions, specifically our awareness and decision-making behavior, are powerful explanatory factors of increasing disaster losses. Disaster mitigation through addressing human, social, and physical vulnerability is one of the best means for contributing to ‘climate change adaptation plans’, and sustainable development goals. Recent lessons from various countries have depicted that the formulation of mitigation strategies cannot be exclusively top-down as it requires social, political, and cultural acceptance and sense of ownership. An interactive, participatory process, involving local communities, produces best expected outcomes concerning mitigation, preparedness, and recovery. An emerging consensus is that there is a need to move towards the ‘mission’ of the International Strategy for Disaster Reduction which aims at building disaster resilient communities by promoting increased awareness of the importance of disaster reduction as an integral component of sustainable development, with the goal of reducing human, social, economic and environmental losses due to natural hazards and related technological and environmental disasters. Sharing of best practices and lessons globally is certain to produce more efficiency and understanding in policy and decision making.  相似文献   
482.
The effect of queen pheromones on worker honey bee ovary development   总被引:11,自引:4,他引:11  
We report results that address a long-standing controversy in honey bee biology, the identity of the queen-produced compounds that inhibit worker honey bee ovary development. As the honey bee is the only organism for which identities have been proposed for any pheromone that regulates reproduction, the resolution of its identity is of broad significance. We examined the effects of synthetic honey bee queen mandibular pheromone (QMP), four newly identified queen retinue pheromone components, and whole-queen extracts on the ovary development of caged worker bees. The newly identified compounds did not inhibit worker ovary development alone, nor did they improve the efficacy of QMP when applied in combination. QMP was as effective as queen extracts at ovary regulation. Caged workers in the QMP and queen extract treatments had better developed ovaries than did workers remaining in queenright colonies. We conclude that QMP is responsible for the ovary-regulating pheromonal capability of queens from European-derived Apis mellifera subspecies.  相似文献   
483.
使用浸渍法制备的CuO Al2 O3催化剂对吸附苯酚饱和的活性炭进行非均相催化湿式氧化再生研究 ,考察了反应温度、反应时间、催化剂投加量、反应氧分压、投炭量、蒸馏水量对非均相催化湿式氧化再生活性炭的影响结果 ,同时在该实验中得到非均相CuO Al2 O3催化湿式氧化再生活性炭的最佳条件。对催化剂进行了X衍射分析 ,并通过对催化剂的稳定性进行实验 ,得出该催化剂在进行催化湿式氧化再生活性炭的过程中具有较好的稳定性  相似文献   
484.
The chemical degradation of synthetic azo dyes color index (C.I.) Acid Orange 7, C.I. Direct Orange 39, and C.I. Mordant Yellow 10 has been studied by the following advanced oxidation processes: Fenton, Fenton-like, ozonation, peroxone without or with addition of solid particles, zeolites HY, and NH4ZSM5. Spectrophotometric (UV/visible light spectrum) and total organic carbon measurements were used for determination of process efficiency and reaction kinetics. The degradation rates are evaluated by determining their rate constants. The different hydroxyl radical generation processes were comparatively studied, and the most efficient experimental conditions for the degradation of organic azo dyes solutions were determined.  相似文献   
485.
Bioleaching processes have been demonstrated to be effective technologies in removing heavy metals from wastewater sludge, but long hydraulic retention times are typically required to operate these bioprocesses. A hybrid process (coupling biological and chemical processes) has been explored in laboratory pilot-scale experiments for heavy metals (cadmium [Cd], copper [Cu], chromium [Cr], and zinc [Zn]) removal from three types of sludge (primary sludge, secondary activated sludge, and a mixture of primary and secondary sludge). The hybrid process consisted of producing a concentrate ferric ion solution followed by chemical treatment of sludges. Ferric iron solution was produced biologically via oxidation of ferrous iron by A. ferrooxidans in a continuous-flow stirred tank (5.2 L) reactor (CSTR). Wastewater sludge filtrate (WSF) containing nutrients (phosphorus and nitrogen) has been used as culture media to support the growth and activity of indigenous iron-oxidizing bacteria. Results showed that total organic carbon (TOC) concentrations of the culture media in excess of 235 mg/L were found to be inhibitory to bacterial growth. The oxidation rate increased as ferrous iron concentrations ranged from 10 to 40 g Fe2+/L. The percentage of ferrous iron (Fe2+) oxidized to ferric iron (Fe3+) increased as the hydraulic retention time (HRT) increased from 12 to 48 h. Successful and complete Fe2+ oxidation was recorded at a HRT of 48 h using 10 g Fe2+/L. Subsequently, ferric ion solution produced by A. ferrooxidans in sludge filtrate was used to solubilize heavy metals contained in wastewater sludge. The best solubilization was obtained with a mixture of primary and secondary sludge, demonstrating a removal efficiency of 63, 71, 49, and 80% for Cd, Cu, Cr, and Zn, respectively.  相似文献   
486.
An activated carbon bed adsorption process is influenced by the adsorbents' characteristics, volatile organic compound (VOC) characteristics, and process conditions. In the literatures, the adsorption processes of the adsorbents and VOCs were usually considered to be in equilibrium. In this study, the VOC adsorption processes by activated carbon were considered to be a kinetic process, i.e. they are not in equilibrium. Then, isothermal adsorption curves and a small column experiment were simulated.  相似文献   
487.
Concentrations of 2,3,7,8-chlorine substituted PCDDs, PCDFs, selected PCB congeners and HCB were determined in sediment samples collected from sites along the east coast of Queensland in northern Australia. PCDDs were detectable in all sediment samples while PCDFs, PCBs and HCB were mainly found in sediment samples collected from sites in the Brisbane metropolitan area. The results provide evidence that an unidentified source for higher chlorinated PCDDs exists along the Queensland coast.  相似文献   
488.
钛白副产硫酸亚铁的综合利用研究   总被引:3,自引:0,他引:3  
以钛白副产硫酸亚铁、氯化钾和氨水为原料,采用硫酸钾铵法制取硫酸钾。实验结果表明,该工艺生产的产品,其质量达到ZBG-21006-89国家标准,且此工艺流程简单、操作方便、条件易控制,无二次污染。  相似文献   
489.
Ohne Zusammenfassung Online First: 27. 03. 2002 ‚Sustainable Substitution of Hazardous Substances‚; Projektbeschreibung unter wwwoekopolde oder wwwfh-hamburgdelpers/gleich_von bzw. www.uni-hamburgde/kooperationssteI1e-hh. Das Vorhaben wird vom Bundesministerium für Bildung und Forschung (BMBF) im F?rderschwerpunkt ‚Rahmenbedingungen für Innovationen zum nachhaitigen Wirtschaften’ (RIW) gef?rdert und von der GSF als Projekttr?ger betreut (FkZ. O7Riw4).  相似文献   
490.
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