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51.
The results from a semi-experimental study of Swedish students’ stated willingness to purchase emission allowances for carbon dioxide are presented. Drawing heavily on recent developments in the literature on integrating norm-motivated behaviour into neoclassical consumer theory, it is assumed that individuals have a preference for maintaining a self-image as a responsible (and thus norm-compliant) person. The results indicate that students’ willingness to purchase carbon allowances is determined by both price and the presence of norms: those who feel personally responsible for contributing to reducing climate damages also appear more inclined to buy allowances. The empirical findings are consistent with the notion that a person's beliefs about others’ stated willingness to purchase carbon allowances imply improvements in their own self-image and ultimately behavioural change. This suggests that information campaigns that attempt to influence beliefs about others’ intentions could promote ‘green’ consumer behaviour in the carbon allowance market. Such (stated) behaviour also appears to be influenced by a person's awareness of the problem of climate change and their beliefs about their own ability to contribute to solving it.

Policy relevance

Although there is a concern that public goods such as reduced climate change may be under-provided in the free market, individual concern for the environment occasionally has profound impacts on consumer choice and voluntary action. This research suggests that information campaigns that attempt to influence beliefs about others’ intentions could promote ‘green’ consumer behaviour in carbon allowance markets. Publicly-provided information about the impacts of climate change and the ways in which these damages stem from individual choices could also induce this type of behaviour.  相似文献   
52.
The effectiveness of 10 Indian mustard (Brassica juncea L.) genotypes (viz. Agrani, BTO, Kranti, Pusa Bahar, Pusa Basant, Pusa Bold, Pusa Jai Kisan, Vaibhav, Vardhan, and Varuna) were evaluated for their potential to phytoremediate copper from contaminated waters under laboratory controlled conditions. The genotypes were grown for 20 days in aqueous solutions containing various concentrations of copper sulfate (0–50 µM) in a hydroponic chamber. Throughout plant development, changes in growth variables, biomass accumulation, and total Cu content were evaluated. The results suggested that Indian mustard cv. Pusa Jai Kisan possesses the best capacities of Cu sequestration and tolerance amongst all the genotypes studied. Thus, Pusa Jai Kisan has the greatest potential to become a viable candidate in the development of practical phytoremediation technologies for Cu contaminated sites.  相似文献   
53.
阻尼对地下隧道结构动力响应的影响   总被引:1,自引:0,他引:1  
徐英乾  戚承志  沙曼 《岩土力学》2012,33(Z2):196-200
用弹性地基梁来模拟地下隧道结构,推出考虑弯曲、轴力、剪切、内外阻尼以及在双参数地基模型上的振动方程。引用地下管道近似的位移计算方法,计算地下隧道结构,避免积分变换的繁琐,通过一种特殊的分离变量法,使得动力荷载以强加位移和速度的方式施加,实例计算中涉及内外阻尼项,可以方便地求出自振频率和阻尼比的表达式和考虑阻尼后结构位移衰减曲线,得出对于地下结构内阻尼的影响很小的结论。  相似文献   
54.
中国最老岩石和锆石   总被引:18,自引:12,他引:6  
在中国大陆的许多地区都已发现大于3.4Ga的锆石和岩石.鞍山是全球仅有几个存在≥3.8Ga岩石的地区之一.它们以不大的规模存在于白家坟、东山、深沟寺杂岩中,由糜棱岩化奥长花岗岩、条带状奥长花岗岩和变质石英闪长岩组成.近年来,在鞍山地区还发现了许多3.7~3.6Ga岩石和锆石.锆石Hf同位素组成表明鞍山地区在3.8~3.6Ga期间存在周期性的地幔添加和陆壳形成.除鞍山外,在中国许多地区的不同类型岩石中也获得了≥3.4Ga锆石,虽然它们大多数都是碎屑和残余成因.(1)华北克拉通冀东铬云母石英岩中3.85~3.55Ga碎屑锆石:(2)华北克拉通信阳中生代火山岩长英质麻粒岩中3.66Ga岩浆锆石;(3)华南克拉通宜昌地区杨子地块新元古代砂岩中3.80Ga碎屑锆石(一颗);(4)华南克拉通华夏地块新元古代一古生代变质沉积岩中3.76~3.6Ga碎屑锆石;(5)西北地区塔里木地块阿克塔什塔格地区古元古代片麻状花岗岩中3.6Ga残余锆石;(6)西秦岭奥陶纪变质火山岩中4.08Ga捕掳锆石(一颗);(7)西藏普兰地区奥陶纪石英岩中4.1Ga碎屑锆石(一颗,有3.61Ga增生边).一些古老锆石有高达4.1~4.0Ga的Hf同位素模式年龄.在中国,>3.4Ga地壳物质的比例以往被低估了,发现冥古宙和始太古代物质的可能性仍然存在,它们将对中国早期陆壳演化提供新的制约.  相似文献   
55.
海底铁锰结壳和结核是重要的海底矿产资源,蕴含着丰富的金属元素并且具有巨大的经济价值。本文主要以南海多金属结壳(核)为研究对象,采用X射线粉晶衍射(XRD)、激光拉曼光谱、红外光谱分析(FTIR)以及X射线光电子能谱对铁锰矿物的矿物学和谱学特征进行了系统的分析和研究。粉晶衍射和拉曼光谱分析结果表明,南海多金属结壳的矿物组成为水羟锰矿、石英和长石,结核的矿物组成为钡镁锰矿、水羟锰矿、石英和长石,铁相矿物均为无定形铁氧化物/氢氧化物,并且锰相矿物和铁相矿物的结晶程度均较差。红外光谱分析结果显示多金属结核和结壳中的铁锰矿物具有大量表面羟基,这些含质子表面羟基官能团,可为海水中各成矿元素的络合提供丰富的活性位点。XPS分析表明多金属结核和结壳中铁锰矿物表面以Fe、Mn和O元素为主,其中Fe呈正三价态,Mn以正四、正三价为主,可能还含有少部分正二价态。对比南海多金属结壳(核)与太平海山结壳,南海多金属结壳(核)具有更为显著的表面羟基氧(-OH)含量,而太平洋海山结壳则以晶格氧(O2-)为主,表明太平洋海山结壳铁锰矿物结晶程度较南海多金属结壳(核)高。综合研究表明,在海底铁锰结壳和结核中(氢)氧化锰/铁矿物与海水之间界面效应对金属离子的富集机理主要有:(1)金属离子与矿物表面羟基进行络合反应,形成以配位键相连的羟基络合物,或与表面的质子交换生成稳定的内层络合物;(2)矿物的带电表面与金属离子通过静电作用形成双电层,生成外层络合物;(3)金属离子与矿物结构中的Mn、Fe离子同晶置换而成为结构阳离子。  相似文献   
56.
Macrofaunal communities of the Central Indian Basin (CIB) were sampled with a spade before (June 1997), and immediately after (August 1997), and 44 months (April 2001) after a simulated benthic disturbance for polymetallic nodule mining. The average density recorded down to a sediment depth of 40 cm ranged from 89 to 799 ind·m-2 (mean: 373 ± 221 SD; n = 12) and 178-1066 ind·m-2 (mean: 507 ± 489 SD; n = 3) in the test and reference area, respectively. Most of the macrobenthic animals (64%) were concentrated in the upper 0 to 2 cm sediment layers, whereas, sizeable fauna (6%) inhabited the 20-40 cm sediment section and the deepest 5 cm section from 35-40 cm contributed only about 2% to the total population density. The fauna, comprised of 12 groups, were dominated by the nematodes, which constituted 54% of the total population. The macrofaunal density in the test site showed a significant increase (x:400 ind·m-2) in the 44 months postdisturbance sampling (x:320 ind·m-2). The population of nematodes and oligochaetes was nearly restored after 44 months, but the polychaetes and crustaceans did not reach the baseline populations measured in June 1997. The top 0-2 cm sediment layer was severely affected by the disturber, and the study suggests that physically disturbed deep-sea macrofauna may require a longer period for restoration and resettlement than normally believed.  相似文献   
57.
58.
In the weeks following the 2011 Rena oil spill, a series of surveys was initiated on eight rocky intertidal reefs to describe the distribution of oil and to assess the impacts of oil on ecological communities. Consistent but relatively low cover of oil occurred at two sites (Mt Maunganui and Moturiki). The area covered by oil had decreased by c. 90% after 5 months due to natural weathering processes. There were immediate effects of oil fouling on the mussel Limnoperna pulex and its associated fauna, with reductions in the number of mussels and infaunal taxonomic richness. However, no ecological effects on any of the communities were detectable after 1 month. Overall, the ecological effects of the Rena oil spill on rocky shore intertidal communities were small and not long-lasting, but we stress that this does not consider potential sublethal effects and their consequences on organisms.  相似文献   
59.
The Cawthron Institute Culture Collection of Micro-algae (CICCM) is a unique, nationally and internationally significant collection of 450 strains of approximately 100 micro-algae and 50 cyanobacteria species, both living and cryopreserved. The collection comprises 13 taxonomic classes and underpins research into the ecology and taxonomy of the isolates and the biotoxins they produce and their toxicity. The CICCM expanded significantly in the 1990s after a major harmful algae bloom event in the Hauraki Gulf, New Zealand. Since 2000, it has underpinned development of molecular detection tools and enabled development of new chemical testing methods for biotoxins in seafood. The tropical collection allows research into potential issues for New Zealand as the oceans warm, for example, the risks of ciguatera fish poisoning and palytoxins in seafood. Research results generated from isolates in the cyanobacterial collection have assisted national risk management regarding drinking water and informed the development of the New Zealand guidelines for managing cyanobacteria in recreational fresh waters. The actual living and cryopreserved micro-algae and cyanobacteria collection (without infrastructure) has a current estimated value of NZ$1.6 million.  相似文献   
60.
潘岳  撒占友  贺可强 《岩土力学》2005,26(11):1695-1699
在体积应变为零的条件下,根据巷道围岩属简单加载的特性得到围岩中同时关联三向应力 , , 和三向应变 , , 的,用等效应力 和等效应变 表示的对围岩加载-形变关系式。严格地论证了巷道围岩的弹性、硬化、软化和流动区的应力应变状态分别与围岩的等效应力-等效应变曲线各阶段的应力应变状态相对应。以等效应力、等效应变为中间变量可以简化围岩弹性分析,简捷地写出巷道围岩偏应力应变能的计算公式。等效剪应力 是围岩中的最大剪应力 ,等效剪应力单元受正应力和剪应力作用,但其上只有剪切应变,这突出了巷道围岩形变破坏是由于最大剪应力和偏应力应变能所致的实质。根据等效剪应力概念确定的滑移线,可适用于材料应变硬化和软化阶段,不要求刚塑性假定条件。  相似文献   
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