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71.
The empirical evidence that economies predominantly reliant on their natural resources are characterized by slower economic growth—the so-called Resource Curse (RC)—is in many ways confirmed by the case of Zambia. Haber and Menaldo (Am Polit Sci Rev 105(1):1–26, 2011) identify Zambia’s extreme dependence on copper exports as one of the worldwide most striking examples for a country suffering from this “curse.” In topical literature, the RC is traced back to the generation of natural resource rents regardless of economic performance, which among other problems leads to suboptimal reinvestment. The World Banks indicator for the “weak” sustainable development of a country—the so-called Genuine Savings (GS)—considers exactly this reinvestment of rents from the depletion of natural capital rents into physical or human capital. Although it has been shown empirically that countries dependent on primary exports on average feature negative GS rates and that the determinants of the RC influence both present economic growth and future sustainability as measured by GS, no case studies have been conducted to confirm this. Against this background, we qualitatively survey the relationship between the most discussed determinants causing the RC in Zambia and the country’s GS rate. We show that all theoretical relationships between the GS rates of a country and RC determinants such as consumption behavior, volatile world market prices, the so-called Dutch disease as well as political and institutional structures apply to Zambia between 1964 and 2010: an extreme dependency on copper exports and insufficient reinvestments of income from the depletion of Zambia’s natural capital constitutes one of the main reasons for slow growth and negative GS until the copper price booms in the second half of the 2000s.  相似文献   
72.
Cunliffe AM  Williams PT 《Chemosphere》2006,62(11):1846-1855
The development of an analytical method for the analysis of PCDD/PCDF in flyash using a bench analytical system comprising of a gas chromatograph fitted with an ion trap detector operated in the tandem MS mode is described. The optimum settings for the most important MS/MS parameters are given, including those for the less reported mono- to tri-chlorinated dioxin and furan congener groups. Flyash samples from three waste incineration plants representing a decommissioned 1970s plant design, an upgraded and still operating plant originally designed in the 1970s, and a modern 1990s design operating plant have been analysed for PCDD/PCDF. The flyash samples were analysed for PCDD/PCDF using the methods developed and the total PCDD/PCDF, I-TEQ values and isomeric profiles are reported. The flyash from the older decommissioned incinerator had very significantly higher concentrations of PCDD/PCDF compared to the modern incinerator flyash.  相似文献   
73.
A sediment cloud release in stagnant ambient fluid occurs in many engineering applications. Examples include land reclamation and disposal of dredged materials. The detailed modeling of the distinct characteristics of both the solid and fluid phases of the sediment cloud is hitherto unavailable in the literature despite their importance in practice. In this paper, the two-phase mixing characteristics of the sediment cloud are investigated both experimentally and theoretically. Experiments were carried out to measure the transient depth penetration and the lateral spread of the sediment cloud and its entrained fluid using the laser induced fluorescence technique, with a range of particle sizes frequently encountered in the field (modeled at laboratory scale). A two-phase model of the sediment cloud that provides detailed predictions of the mixing characteristics of the individual phases is also proposed. The entrained fluid characteristics are solved by an integral model accounting for the buoyancy loss (due to particle separation) in each time step. The flow field induced by the sediment cloud is approximated by a Hill’s spherical vortex centered at the centroid and with the size of the entrained fluid. The particle equation of motion under the effect of the induced flow governs each computational particle. A random walk model using the hydrodynamic diffusion coefficient is used to account for the random fluctuation of particles in the dispersive regime. Overall, the model predictions of the two-phase mixing characteristics are in good agreement with the experimental data for a wide range of release conditions.  相似文献   
74.
This article describes the influence of dissolved copper on the electrokinetic properties and transport of a copper oxychloride-based fungicide (COF) in porous media. The Zeta potential (ζ) of COF particles increases (viz. becomes less negative) with increasing concentration of Cu(2+) in the bulk solution. ζ decreases for COF when the electrolyte (NaNO(3)) concentration is raised from 1 to 10mM. This can be ascribed to ion correlation of Cu(2+) in the electrical double layer (EDL). COF transport tests in quartz sand columns showed the addition of Cu(2+) to the bulk solution to result in increased retention of the metal. Modelling particle deposition dynamics provided results consistent with kinetic attachment. Based on the effect of soluble Cu on colloid mobility, the transport of particulate and soluble forms of copper is coupled via the chemistry of pore water and colloid interactions. Mutual effects between cations and colloids should thus be considered when determining the environmental fate of particulate and soluble forms of copper in soil and groundwater (especially at copper-contaminated sites).  相似文献   
75.
OBJECTIVES: Passenger vehicle driver death rates per million vehicle registrations declined steadily during calendar years 1985-2004. The present study sought to separate the effect of vehicle design changes from this trend. METHODS: Restricting the trend to a fixed set of model years removed the vehicle design effects, but there were still effects due to vehicle aging. Risk of driver death was found to increase each year vehicles aged, probably due to changes in vehicle use patterns. RESULTS: After separating out the vehicle design effects and making adjustments for the vehicle age effects, a different picture emerged of trends in death rates over time. Absent the vehicle design changes, the historical decline in driver fatality risk would have ended in 1993, with risk climbing ever since. This underlying trend has been obscured by changes in the vehicle fleet. CONCLUSIONS: The push for vehicle improvements has been worthwhile and can be credited with saving thousands of lives. However, the analysis shows that the gains in occupant protection from vehicle design improvements have been offset partially by an increasingly risky environment in recent years. Therefore, more attention needs to be paid to programs targeting improvement in roadway design and driver behavior.  相似文献   
76.
Dead and deformed grey heron (Ardea cinerea) chicks were reported at a large heronry in North Nottinghamshire, UK between 1996 (when systematic visits to the heronry started) and 2002. Many of the birds died for no obvious reason but deformities in others included multiple fractures of the tarsus and tibia and metacarpal bones (angel wings). This study aimed to investigate possible chemical causes of these deformities. Analysis of eggs and nestling tissue for a range of metals showed no levels of concern and no significant differences between unaffected and deformed birds. However, the levels of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) detected in affected heron nestlings in 2002 and in eggs taken from nests in 2003 were sufficiently high to suggest that this may be the underlying cause of the deformities, possibly due to effects on deposition of calcium in bone. Further work is underway to identify where the parent birds of the affected nestlings are feeding and identify the possible source of the pollution.  相似文献   
77.
This paper assesses the contribution of land-use planning to the objectives of local sustainable development in some of the UK's most urbanized areas. Sustainable development provides the context within which local planning policies are now being prepared, and can be seen to be a potentially important aspect of central government's proposals for modernizing local government. Using the results from a comprehensive survey of development plans in metropolitan authorities, the paper assesses both the strengths and the weaknesses of land-use planning in terms of sustainable development and speculates upon the lessons they may offer to the government's more recent proposals on modernizing local government.  相似文献   
78.
ABSTRACT: Nine flood-estimation models used for ungauged urban watersheds in Louisiana were evaluated. Flood-quantile predictions from simple regression models calibrated by local data were found to be more reliable than those more complicated models or models with many parameters that may not be accurately estimated. Flood prediction from models developed by using regionalization techniques were found to be reasonably good. Finally, application of a model outside of its limitations or domain may lead to substantial prediction error.  相似文献   
79.
The growing complexity and global nature of wildlife poaching threaten the survival of many species worldwide and are outpacing conservation efforts. Here, we reviewed proximal and distal factors, both social and ecological, driving illegal killing or poaching of large carnivores at sites where it can potentially occur. Through this review, we developed a conceptual social–ecological system framework that ties together many of the factors influencing large carnivore poaching. Unlike most conservation action models, an important attribute of our framework is the integration of multiple factors related to both human motivations and animal vulnerability into feedbacks. We apply our framework to two case studies, tigers in Laos and wolverines in northern Sweden, to demonstrate its utility in disentangling some of the complex features of carnivore poaching that may have hindered effective responses to the current poaching crisis. Our framework offers a common platform to help guide future research on wildlife poaching feedbacks, which has hitherto been lacking, in order to effectively inform policy making and enforcement.  相似文献   
80.
The detection of trace levels of a range of organic contaminants (including pesticides, toxins and an explosive) in potable water, using cryoprobe NMR spectroscopy with limited sample preparation and rapid acquisition times, is described. Emphasis is placed on the applicability of NMR spectroscopy for use in emergency scenarios as the unbiased nature of the technique facilitates the detection and characterization of unknown compounds at levels as low as 50 microg L(-1).  相似文献   
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