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1.
We show that for a broad class of technologies the relationship between policy stringency and the rate of technology adoption is inverted U-shaped. This happens when the marginal abatement cost (MAC) curves of conventional and new technologies intersect, which invariably occurs when emissions are proportional to output and technological progress reduces emissions per output. This outcome does not result from policy failure. On the contrary, in social optimum, the relationship between the slope of the marginal damage curve and the rate of technology adoption is also inverted U-shaped. Under more general conditions, these curves can look even more complicated (e.g., such as inverted W-shaped).  相似文献   

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Encouraging the use of more efficient irrigation technology is often viewed as an effective, politically feasible method to reduce the consumptive use of water for agricultural production. Despite its pervasive recommendation, it is not clear that increasing irrigation efficiency will lead to water conservation in practice. In this paper, we evaluate the effect of a widespread conversion from traditional center pivot irrigation systems to higher efficiency dropped-nozzle center pivot systems that has occurred in western Kansas. State and national cost-share programs subsidized the conversion. On an average, the intended reduction in groundwater use did not occur; the shift to more efficient irrigation technology has increased groundwater extraction, in part due to shifting crop patterns.  相似文献   

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This paper explores the characteristics of 238 patents on 90 inventions contributed by major multinational innovators to the “Eco-Patent Commons”, which provides royalty-free access to third parties to patented innovations on green technologies. We compare the pledged patents to other patents in the same technologies or held by the same multinationals to investigate the motives of the contributing firms as well as the potential for such commons to encourage innovation and diffusion of climate change related technologies. We find pledged patents to protect environmentally friendly technologies and to be of similar value as the average patent in a pledging firm's patent portfolio but of lower value than other patents in their class. Our analysis of the impact of the patent commons on diffusion of patented technologies suggests that making patents accessible royalty-free did not result in any significant increase in diffusion as measured by citing patents. This study, therefore, indirectly provides evidence on the role of patents in the development and diffusion of green technologies.  相似文献   

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Federal, state, and local governments use a variety of incentives to induce consumer adoption of hybrid-electric vehicles. We study the relative efficacy of state sales tax waivers, income tax credits, and non-tax incentives and find that the type of tax incentive offered is as important as the generosity of the incentive. Conditional on value, sales tax waivers are associated with more than a ten-fold increase in hybrid sales relative to income tax credits. In addition, we examine how adoption varies with fuel prices. Rising gasoline prices are associated with greater hybrid vehicle sales, but this effect operates almost entirely through high fuel-economy vehicles. By comparing consumer response to sales tax waivers and estimated future fuel savings, we estimate an implicit discount rate of 14.6% on future fuel savings.  相似文献   

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An investigation into emergency potable water treatment technologies was conducted to investigate China’s water pollution situation. In order to confirm optimum parameters, the technological efficiency of each pollutant was obtained. About 100 contaminants were tested to find the emergency treatment technologies, most of which were found to be positive. This paper presents the three largest and most significant water pollution incidents in China to date, analyzing cases such as the nitrobenzene pollution incident in the Songhua River in November 2005, the cadmium pollution incident in the Beijiang River in December 2005, and the water crisis with odorous tap water in Wuxi City in May 2007.  相似文献   

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The purpose of this paper is to illuminate the spatio-temporal diffusion of rooftop household photovoltaic installations in Germany and to test whether localized imitation drives their adoption. Our study is based on a unique data set of some 576,000 household photovoltaic systems installed in Germany through 2009. We employ an epidemic diffusion model which includes a spatial dimension, and control for temporal and spatial heterogeneity. According to our results, imitative adoption behavior is highly localized and an important factor for the diffusion of household photovoltaic systems.  相似文献   

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This study evaluated the feasibility of integrating amorphous magnesite and bentonite clay (composite) as an alternative technology for removing arsenic from industrial effluents. The removal of arsenic from industrial effluents by using magnesite–bentonite clay composite was carried out in batch mode. The effects of equilibration time, adsorbent dosage, adsorbate concentration, and pH on removal of arsenic were investigated. The experiments demonstrated that ≈100% arsenic removal is optimum at 30 minutes of agitation, 2 g of adsorbent dosage (2 g: 100 mL, S/L ratio), and 20 mg L?1 of arsenic concentration. The adsorption data fitted well to both Langmuir and Freundlich adsorption models, hence proving monolayer and multilayer adsorption. The kinetic studies revealed that the data fitted better to a pseudo-second-order reaction than to a pseudo-first-order reaction, hence proving chemisorption. At optimized conditions, the composite was able to remove arsenic to below World Health Organization water quality guidelines, hence depicting that the composite is effective and efficient in removing arsenic from contaminated water. Based on that, this comparative study proves that the composite is a promising adsorbent with high adsorption capacity for arsenic and can be a suitable substitute for the conventional treatment methods.  相似文献   

8.
The rhizospheric soils of Tieguanyin at different ages were used as the study materials, and terminal-restriction fragment length polymorphism (T-RFLP) was used to analyze the changes in bacterial diversity. The results showed that the number of T-RFs, Simpson index, and Shannon index decreased significantly with the age of the tea tree. Results of correlation analysis showed that 9 T-RFs from the bacterial community were significantly and positively correlated with the age of the tea tree, and included 34 species of microbes belonging to 10 classes. The 34 microbes were divided into 6 types according to their functional attributes, and included pathogenic bacteria, bacteria that improved soil texture or inhibited pathogenic bacteria, and bacteria associated with the carbon, nitrogen, or sulfur cycles, in which the percentage of pathogenic bacteria was 58.82%. Seventeen T-RFs were significantly and negatively correlated with the age of the tea tree, and included 38 species of bacteria belonging to 12 classes. The 38 bacterial species were divided into 5 types according to their functional attributes, and included pathogenic bacteria, bacteria that improved soil quality or inhibited pathogenic bacteria, and bacteria associated with the carbon cycle or nitrogen cycle, in which all the others, barring the pathogenic bacteria, accounted for 78.95% of the bacterial population. In brief, the diversity and function of bacteria in the rhizospheric soil of tea tree changed significantly with the age of the tea tree, which provides a theoretical basis for studying the interactions of bacterial communities. © 2018 Science Press. All rights reserved.  相似文献   

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研究拟定了九种元素的ICP-AES分析方法.检出限在0.0004μg/ml—0.003μg/ml之间,利用自行研制的热化学反应炉电热蒸发装置,将水样蒸发浓缩,用载体吸附后烘干,再与反应剂混合后送入反应炉内发生定向热化学反应,用载气将分析元素的反应蒸气带入等离子体进行光谱方法分析.对主要的测定参量进得了试验,对基盐影响进行了研究,用拟定的方法对As,Cd,Pb三元素的水标准参考样进行了测定,分析结果与标准值相当一致.对不同含量的标准进行了多次回收测定,取得了比较满意的结果.此方法能满足水中痕量元素分析的需要。  相似文献   

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Nucleic acids and their analogues are getting more and more attention. Metal-mediated base pairs as a kind of simple and functionalized nucleic acids in special positions have widened the scope of application of functional nucleic acids and their analogues. In this type of base pairs, the representative is the interaction between metal ions and pyrimidine bases, especially the research on thymine-Hg2+-thymine (T-Hg2+-T) and cytosine-Ag+-cytosine (C-Ag+-C) base pairs. This review summarizes the structure and mechanism of metal-mediate pyrimidine base pairs as well as the application in the biochemical analysis. It explores the mode and ratio of coordination between metal ions and base pairs, the effects on the stability of DNA helical structure, the related crystal structure and the three-dimensional configuration information in the DNA helix. The analytical application mainly includes various probes of metal ions, small molecules, protein and the detection of single nucleotide polymorphism. Among them the most widely used metal ions detection, and its combination with spectrum technology, visualization and amplification technology greatly promoted the rapid development of sensitive detection technology. In further studies, it is necessary to reveal the mechanism of interaction between T-Hg2+-T and C-Ag+-C, and more attention should be paid to combining of T-Hg2+-T and C-Ag+-C base pairs with other new technologies. The scope of practical application should also be further extended.  相似文献   

15.
重金属Cu,Pb,Zn,Cr,Cd在水稻植株中的富集和分布   总被引:103,自引:0,他引:103  
研究了外源可溶性重金属进入水稻土环境后,在水稻植株中的迁移、在水稻植株不同部位的分布及其分布随时间的变化。在水稻生长季节,重金属在水稻植株中迁移能力的大小依次为:Cd,Cr>Zn,Cu>Pb。重金属在水稻植株不同部位的积累分布是:根部>根基茎>主茎>穗>籽实>叶部。水稻分蘖期重金属在根部、茎干部和叶片的积累量达到最大,随着时间的延长,在根部积累的重金属愈来愈少;在茎干部积累的重金属在拔节期降至最小,随后含量又稍微上升;叶片上的重金属含量在拔节期迅速下降,随后趋于稳定。  相似文献   

16.
Data from National Health and Nutrition Examination Survey for children aged 6–11 years for 1999–2014 were used to study time trends and factors affecting the urinary levels of barium, cobalt, cesium, molybdenum, lead, antimony, thallium, and tungsten. Adjusted levels in urine declined every two years by 5.9% for barium, by 1.2% for cesium, by 18.2% for lead, and by 14% for antimony. For every additional smoker smoking inside a home, the levels of barium increased by 10.6% and for lead by 10%, but for tungsten levels decreased by 7.7%.  相似文献   

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本文主要研究了南黄海(32°N)沉积物间隙水中的Fe,Mn,Cu,Co,Ni与其硫化物及粘土矿物间的关系,结果表明:间隙水中的Mn~(2+),Cu~(2+)硫化物趋向于沉淀,Co~(2+),Ni~(2+)硫化物趋向于溶解,Fe~(2+)则有其硫化物的溶解-沉淀控制,Mn~(2+),Cu~(2+)还有其他体系和硫化物体系共同控制其浓度,间隙水中的Fe~(2+)可被蒙脱石吸附,Mn~(2+)被绿泥石吸附,Ca~(2+),Ni~(2+)被蒙脱石、绿泥石吸附,Co~(2+)被绿泥石、蒙脱石吸附,Fe~(2+),Mn~(2+)对粘土矿物吸附剂的专属性要求远比Cu~(2+),Co~(2地+),Ni~(2+)高,蒙脱石是南黄海沉积物中最重要的阳离子吸附剂,绿泥石次之。  相似文献   

20.
温度,碳,氮,磷对一株芽孢杆菌生长的影响   总被引:10,自引:0,他引:10  
A series of orthogonal array tests and single-factor tests were designed to study the growth of Bacillus sp. H strain isolated from Microcystis aeruginosa in the Taihu Lake. The results indicated that within the experimental scope the factors affecting the growth of Bacillus sp. H strain were arranged in the order organic carbon>temprature>phosphate>ammonium. Of the four factors, organic carbon and temperature most significantly affected the growth of Bacillus sp. H strain. It was also found that with the raising of temperature, concentration of organic carbon or the ratio of N/P, the growth of Bacillus sp. H strain would become better. The optimum conditions for the growth of Bacillus sp. H strain in this experiment weretemperature 30, concentration of ammonium 0.520 g/L , concentration of peptone 2.0 g/L , phosphate 0.088 g/L , and organic carbon 2.28 g/L. Fig 4, Tab 2, Ref 5  相似文献   

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