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251.
252.
Few studies have explored the relationships between nation‐building, disaster risk reduction and climate change adaptation. Focusing on small island developing states, this paper examines nation‐building in Timor‐Leste, a small island developing state that recently achieved independence. Nation‐building in Timor‐Leste is explored in the context of disaster risk reduction, which necessarily includes climate change adaptation. The study presents a synopsis of Timor‐Leste's history and its nation‐building efforts as well as an overview of the state of knowledge of disaster risk reduction including climate change adaptation. It also offers an analysis of significant gaps and challenges in terms of vertical and horizontal governance, large donor presence, data availability and the integration of disaster risk reduction and climate change adaptation for nation‐building in Timor‐Leste. Relevant and applicable lessons are provided from other small island developing states to assist Timor‐Leste in identifying its own trajectory out of underdevelopment while it builds on existing strengths.  相似文献   
253.
建筑业是最古老、最重要的工业之一.它提供了庇护,并为许多人类活动提供了物质框架和基础.它使我们得以生存、参加社会活动、利用我们的环境一总之,实现我们的潜力.但是,同时它也限制了我们的潜力,因为它限制了企业、革新、生产力和以及通过解决贫困、社会排斥和气候变化维持增长的能力.本文介绍了欧盟建筑部门的主要特点,探讨了与促进可持续建筑有关的一些问题.重点介绍了中小建筑企业的基本需求以及为满足这些需求而正在采取的措施.欧洲和其他大陆的发达国家可能还有许多东西要向发展中国家的发展途径和项目支持系统学习.  相似文献   
254.
A photochemical model of benzene degradation compares well with experimental data obtained in the Lab. 62 reactions were needed to fully describe benzene degradation. A feasibility study shows that the photolysis of benzene is a cost-effective process. Experimental data and modeling results show that the degradation efficiency will increase when the combination of UV light and ozone is used. The degradation of benzene, a carcinogenic air pollutant, was studied in a gas-phase photochemical reactor with an amalgam lamp emitting ultraviolet light at 185 and 254 nm. Efficient benzene degradation (>70%) was possible for benzene mass flow rates of up to 1.5 mg·min−1. Adding ozone allowed benzene mass flow rates of up to 5 mg·min−1 to be treated with the same efficiency. In terms of energy consumption, ozone doubles the efficiency of the process. A comprehensive mechanistic simulation model was developed incorporating a chemical kinetics model (62 reactions involving 47 chemical species), a material balance model incorporating diffusion and flow, a flow velocity model, and a light field model. The model successfully predicted the efficiency of the reactor, generally within 20%, which indicates that the model is sound, and can be used for feasibility studies. The prediction of the reactor efficiency in the presence of ozone was less successful, with systematically overestimated efficiency. Condensation of reaction products in the reactor is thought to be the main cause of model inaccuracy. Both experimental data and model predictions show that there is a synergistic effect between ozonation and ultraviolet degradation.  相似文献   
255.
One unexplored area in sexual conflict studies is the female physiological costs and possible resource reallocation that accompany evolutionary costs due to male harassment. Using females of the damselfly Hetaerina americana, I first investigated whether male harassment affected female mating rate and survival and explored whether such effects induced a resource allocation from immunity (in the form of phenoloxidase activity) and muscular fat reserves to egg number and size. Using two seasons that differed in male harassment, it was found that the higher the male harassment, the fewer are the female matings and the lower is the female survival. These results were corroborated using an experimental approach in which a situation of high male harassment was induced. It was also found that when the first mating takes place and at high male harassment, females had more reduced phenoloxidase activity and fat reserves and tended to lay most of the eggs they produce in their lifetime and these were considerably large. However, at low male harassment, egg number and size were more equally produced across matings. Females under high male harassment seemed to suffer the survival costs but may show a plastic evolutionary response of reallocating resources to egg traits to maximize fitness.  相似文献   
256.
This paper presents an extension to the Constrained Cellular Automata (CCA) land use model of White et al. [White, R., Engelen, G., Uljee, I., 1997. The use of constrained cellular automata for high-resolution modelling of urban land-use dynamics. Environment and Planning B: Planning and Design 24(3), 323–343] to make it better suited for modelling the dynamics of shifting cultivation. In the extended model the time passed since the last land use transition of a location is a factor of its land use potential. The model can now account for the gradual decrease in soil fertility after an area of forest has been cleared for cultivation and also capture the process of regeneration once the plot is fallowed. The model is applied for the Ruhunupura area of Sri Lanka where chena, a particular practice of shifting cultivation, is a common land use that dominates the landscape dynamics. The model is calibrated for the period 1985–2001 and the results are assessed in terms of location to location overlap as well as structural similarity at multiple scales. These results give confidence in the representation of land use dynamics for the main land use classes. On the basis of a long term scenario run for the period 2001–2030, it is verified that the model captures stylized facts related to chena dynamics, in particular shortening fallow periods and increasingly long cultivation periods of chena, as a result of increasing land use pressure.  相似文献   
257.
Describing contaminant spatial distribution is an integral component of risk assessment. Application of geostatistical techniques for this purpose has been demonstrated previously. These techniques may provide both an estimate of the concentration at a given unsampled location, as well as the probability that the concentration at that location will exceed a critical threshold concentration. This research is a comparative study between multiple indicator kriging and kriging with the cumulative distribution function of order statistics, with both local and global variograms. The aim was to determine which of the four methods is best able to delineate between "contaminated" and "clean" soil. The four methods were validated with a subset of data values that were not used in the prediction. Method performance was assessed by calculating the root mean square error (RMSE), analysis of variance, the proportion of sites misclassified by each method as either "clean" when they were actually "contaminated" or vice versa, and the expected loss for each misclassification type. The data used for the comparison were 807 topsoil Pb concentrations from the inner-Sydney suburbs of Glebe and Camperdown, Australia. While there was very little difference between the four methods, multiple indicator kriging was found to produce the most accurate predictions for delineating "clean" from "contaminated" soil.  相似文献   
258.
259.
In the present study, the impact of sodium metabisulphite (Na2S2O5), a food preservative, on seed germination, growth and yield of Vigna sinensis, Savi has been evaluated. Observations clearly reveal the deleterious effect of Na2S2O5 on germination, stomatal development, stomatal index, chlorophyll content and yield. The shoot length exhibited a steady rise in length, while the biomass showed a gradual decrease with the increasing doses of Na2S2O5.  相似文献   
260.
Landfill cover soils oxidize a considerable fraction of the methane produced by landfilled waste. Despite many efforts this oxidation is still poorly quantified. In order to reduce the uncertainties associated with methane oxidation in landfill cover soils, a simulation model was developed that incorporates Stefan-Maxwell diffusion, methane oxidation, and methanotrophic growth. The growth model was calibrated to laboratory data from an earlier study. There was an excellent agreement between the model and the experimental data. Therefore, the model is highly applicable to laboratory column studies, but it has not been validated with field data. A sensitivity analysis showed that the model is most sensitive to the parameter expressing the maximum attainable methanotrophic activity of the soil. Temperature and soil moisture are predicted to be the environmental factors affecting the methane oxidizing capacity of a landfill cover soil the most. Once validated with field data, the model will enable a year-round estimate of the methane oxidizing capacity of a landfill cover soil.  相似文献   
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