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31.
Pete Quinn 《Natural Hazards》2013,65(3):1227-1248
This paper examines the use of road network data as a proxy for interpreting population density, which is of use in regional-scale qualitative risk assessment for natural hazards. Comparison of available road network and population data at various scales in Ontario and Quebec yields a best-fit relationship of D P  = 28 D R 2 . Analysis of available high-resolution topographic data for the Caribbean island nation of Saint Lucia suggests similar power law trends, with expected population density in Saint Lucia roughly half that of Canada for the same road density. Together, these findings suggest that D P  ~ 10–30 D R 2 may represent a useful range broadly applicable for a wide variety of geographic, climactic and socioeconomic settings. The Canadian relationship has been used to generate a population density model for the lowlands of eastern Ontario and southern Quebec, and this model has been compared with the spatial distribution of seismic hazard to develop a qualitative seismic risk map. The seismic risk map, presented primarily for illustrative purposes, shows elevated seismic risk in urban centers in the study area, and along a predominantly rural area east of Quebec City on both shores of the Saint Lawrence River.  相似文献   
32.
The GENESIS space mission recovered ions emitted by the Sun during a 27 month period. In order to extract, purify and determine the very low quantities of solar nitrogen implanted in the GENESIS targets, a new installation was developed and constructed at the CRPG (Nancy, France). It permitted the simultaneous determination of nitrogen and noble gases extracted from the target by laser ablation. The extraction procedure used a 193 nm excimer laser that allowed for surface contamination in the outer 5 nm to be removed, followed by a step that removed 50 nm of the target material, extracting the solar nitrogen and noble gases implanted in the target. Following purification using Ti and Zr getters for noble gases and a Cu-CuO oxidation cycle for N2, the extracted gases were analysed by static mode (pumps closed) mass spectrometry using electron multiplier and Faraday cup detectors. The nitrogen blanks from the purification section and the static line (30 minutes) were only 0.46 picomole and 0.47 picomole, respectively.  相似文献   
33.
Recognition of the inherent complexities of oil bioassays prompted the development of several apparatuses designed to deliver uniform solutions of the water-soluble components of crude oil and capable of system equilibration for both static and continuous-flow bioassays without the loss of the more volatile compounds and without the formation of emulsions. Clams from a relatively contaminated area exhibited greater resistance to the water-soluble fraction of Cook Inlet crude oil than specimens from a more pristine area. Behaviour was altered below lethal levels suggesting the possibility of using behavioural modifications as a concommitant criterion of toxicity with mortality. An increase in mortality with a longer exposure period and a significant rate of latent mortalities following the end of the 96-h exposure period suggest that future bioassays with bivalves should be determined over a longer exposure period.  相似文献   
34.
35.
This paper derives a notional future carbon budget for UK agriculture, land use, land use change and forestry sectors (ALULUCF). The budget is based on a bottom-up marginal abatement cost curve (MACC) derived for a range of mitigation measures for specified adoption scenarios for the years 2012, 2017 and 2022. The results indicate that in 2022 around 6.36 MtCO2e could be abated at negative or zero cost. Furthermore, in the same year, over 17% of agricultural GHG emissions (7.85 MtCO2e) could be abated at a cost of less than the 2022 Shadow Price of Carbon (£34 (tCO2e)???1). The development of robust MACCs faces a range of methodological hurdles that complicate cost-effectiveness appraisal in ALULUCF relative to other sectors. Nevertheless, the current analysis provides an initial route map of efficient measures for mitigation in UK agriculture.  相似文献   
36.
Future levels of water stress depend on changes in several key factors including population, climate-change driven water availability, and a carbon dioxide physiological-forcing effect on evaporation and run-off. In this study we use an ensemble of the HadCM3 climate model forced with a range of future emissions scenarios combined with a simple water scarcity index to assess the contribution of each of these factors to the projected population living in water stress over the 21st century.Population change only scenarios increase the number of people living in water stress such that at peak global population 65% of people experience some level of water stress. Globally, the climate model ensemble projects an increase in water availability which partially offsets some of the impacts of population growth. The result is 1 billion fewer people living in water stress by the 2080s under the high end emissions scenarios than if population increased in the absence of climate change.This study highlights the important role plant-physiological forcing has on future water resources. The effect of rising CO2 is to increase available water and to reduce the number of people living in high water stress by around 200 million compared to climate only projections. This effect is of a similar order of magnitude to climate change.  相似文献   
37.
Helium‐3 is a stable cosmogenic isotope that can be used to determine the time interval during which a rock sample has been at or close to the Earth’s surface. As a result of the high production rate of ‘cosmogenic’3He (≈ 130 at g?1 year?1) and the low detection limit of modern mass spectrometers, it is possible to date exceptionally young surfaces (≈ 1000 years). The precision and accuracy of cosmogenic 3He measurements depend critically on the passive helium blank (produced by the metalwork of the extraction furnace) which can be significant relative to the sample signals. We have developed and constructed, at the CRPG (Nancy, France), a new high temperature furnace (< 1500 °C) to extract helium in minerals such as apatite, pyroxene and olivine at 1050, 1350 and 1450 °C, respectively. The furnace demonstrated an excellent helium extraction yield (> 99% for olivine and pyroxene for heating times of 20–30 min and temperatures in the range 1050–1450 °C) and low residual helium contributions (the blank, obtained under the same analytical conditions as for sample extraction: 1 × 10?15 mole 4He and < 4 × 10?21 mole 3He). This is approximately an order of magnitude lower than those reported by other laboratories using conventional furnaces.  相似文献   
38.
花岗质岩浆和矿化之间的关系:重要概念和关键特征   总被引:1,自引:0,他引:1  
最近对与花岗岩相关的锂、稀土金属和贱金属(例如Cu和Mo)矿产需求重新激发了人们对其成矿作用研究的兴趣。本文综述了不同类型花岗质岩石及与其相关的矿床:1)与高分异花岗岩有关的浸染状稀有金属矿化;2)热液型锡和钨矿化(如:矽卡岩型矿床);3)伟晶岩型稀有元素矿化;4)斑岩型矿化。虽然花岗岩和相关矿化作用之间(特别是斑岩系统相对于稀有金属)的联系还没有明确,但最近这些成矿系统的相关研究进展为探讨两者之间的关系提供了条件。本文重点回顾了与花岗岩相关成矿作用的主要特征,以及与不同类型矿化有关的花岗质岩浆的多样性,并论述了不同类型矿床的成矿模式。尽管长英质侵入岩浆系统复杂多样,但近来与这些矿化系统有关的研究进展可望能够作为找矿勘探的指示。地球化学特征可以揭示岩浆系统的氧化还原状态,进而可以判断斑岩系统的成矿潜力,它还可以与其他找矿勘探指标如矿物的同位素和微量元素分析联合使用。本文还讨论了通过熔融包裹体分析,研究微量元素在硅酸盐岩浆与挥发分体系中的行为。  相似文献   
39.
ABSTRACT

The Dayinsu area is located in the northern part of the West Junggar district near the border between China and Kazakhstan and is an important component of the Central Asian Orogenic Belt (CAOB). The Dayinsu area hosts numerous granitoid plutons in Devonian–Carboniferous volcano–sedimentary strata. The older Laodayinsu and Kubei (345–330 Ma) plutons are located in the west with the younger Bayimuzha and Qianfeng (330–325 Ma) plutons in the east. The whole-rock SiO2 contents of the four granitoid plutons range from 52.22 to 68.42 wt.% and total alkaline contents (K2O + Na2O) range from 4.94 to 9.16 wt.%. The granites are enriched in large ion lithophile elements and light rare earth elements with depletions in Nb, Ta, Ce, Pr, P, and Ti. The plutons are metaluminous with I-type signatures. The geochemistry of the intrusions suggests that they formed in a subduction zone setting, and subsequently underwent fractional crystallization during emplacement, with higher degrees of fractionation in the eastern sector than in the west. Similarities in the geochronology and geochemical characteristics of the granitoid plutons in Dayinsu to those in the Tabei district (west to Dayinsu area) suggest that both districts are part of the Carboniferous Tarbagatay Mountain intrusive event. The early Carboniferous (345–324 Ma) granitoid intrusions in the Tarbagatay Mountain likely formed in an island arc subduction setting during the evolution of the CAOB.  相似文献   
40.
Julia Bowett  Pete Hay   《Marine Policy》2009,33(5):775-783
This article presents the results of a survey examining the attitudes of young Japanese people towards whaling and its controversies. Using an online and paper-based questionnaire, 529 useable surveys were completed by Japanese students (between 15 and 26 years old) from May to December 2007. Factorial analysis, correlation and regression models were used to identify relational predictors underlying the attitudes of young Japanese people on whaling issues. An approval of whaling exists amongst the participating students, with two constructs standing out as contributing the most to this affirmation; firstly, an approval of the consumption of whalemeat by Japanese children; and secondly, an acceptance of the pro-whaling rhetoric commonly produced by the Government of Japan (GOJ) and associated media. This research represents an initial exploration into the attitudinal structures of Japanese students on whaling issues, contributing to a deeper understanding of the complexities that surround the debate.  相似文献   
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