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711.
This paper attempts to analyse the role of building energy efficiency (BEE) in China in addressing climate change mitigation. It provides an analysis of the current situation and future prospects for the adoption of BEE technologies in Chinese cities. It outlines the economic and institutional barriers to large-scale deployment of the sustainable, low-carbon, and even carbon-free construction techniques. Based on a comprehensive overview of energy demand characteristics and development trends driven by economic and demographic growth, different policy tools for cost-effective CO2 emission reduction in the Chinese construction sector are described. We propose a comprehensive approach combining building design and construction, and the urban planning and building material industries, in order to drastically improve BEE during this period of rapid urban development. A coherent institutional framework needs to be established to ensure the implementation of efficiency policies. Regulatory and incentive options should be integrated into the policy portfolios of BEE to minimise the efficiency gap and to realise sizeable carbon emissions cuts in the next decades. We analyse in detail several policies and instruments, and formulate relevant policy proposals fostering low-carbon construction technology in China. Specifically, Our analysis shows that improving building energy efficiency can generate considerable carbon emissions reduction credits with competitive price under the CDM framework. 相似文献
712.
We present here a terrestrial carbon cycle model based on a scheme of the phytomass change, which is continuous in time. The experimental information about net primary production, living and dead phytomass, and soil organic matter for various ecosystems is used for calibration of the model. The suggested model enables to characterize terrestrial ecosystems as carbon sources or carbon sinks and to evaluate intensity of these sources and sinks. The model is applied for the European territory of Russia as a case study. Intensity of the total exchange carbon flux for this territory is evaluated. The obtained results allow to conclude that the given territory is the sink of carbon. 相似文献
713.
阐述了超临界流体萃取的原理和特点,分析了温度、压力、流体流速、改性剂、络合剂等因素对萃取过程的影响,介绍了超临界CO2萃取技术的优点及其在萃取土壤中的有机污染物、非固体介质中的污染物、环境样品中的金属离子等方面的应用,对该技术的应用前景作了展望。 相似文献
714.
王连弟 《环境监测管理与技术》1997,9(1):36-36,45
在不同的时间段,测定存放于普通球胆及特制的锡箔袋内的一氧化碳标准气的浓度,来春浓度值与贮存时间的关系。通过对3种一氧经碳浓度的测定,证实普通球胆采集的一氧化碳样品,应在当天进行分析;用锡箔气袋,则可保存7-10d。’ 相似文献
715.
Santosh Kumar Mohmmad Y. Wani Joonseok Koh João M. Gil Abilio J.F.N. Sobral 《环境科学学报(英文版)》2018,30(7):77-84
One of today's major challenges is to provide green materials for a cleaner environment. We have conducted studies on carbon dioxide(CO2) adsorption and conversion to valuable products by an ecofriendly approach based in chitosan/graphene oxide(CSGO) nanocomposite film. Rheological behavior indicates that the CSGO has a better solvation property than the pure chitosan. An adsorption capacity of 1.0152 mmol CO_2/g of CSGO nanocomposite at4.6 bar was observed. The catalytic behavior of the CSGO nanocomposite in the presence of tetra-n-butylammonium iodide(n-Bu4 NI) as co-catalyst was evaluated for the cycloaddition of CO_2 to epoxides, to give cyclic carbonates, in the absence of any solvent. These results strongly suggest that the CSGO nanocomposite may open new vistas towards the development of ecofriendly material for catalytic conversion and adsorption of CO_2 on industrial scale. 相似文献
716.
Niobium oxide nanowire-deposited carbon fiber (CF) samples were prepared using a hydrothermal method with amorphous Nb2O5·nH2O as precursor. The physical properties of the samples were characterized by means of numerous techniques, including X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected-area electron diffraction (SAED), UV–visible spectroscopy (UV–vis), N2 adsorption–desorption, Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy. The efficiency for the removal of Cr(VI) was determined. Parameters such as pH value and initial Cr(VI) concentration could influence the Cr(VI) removal efficiency or adsorption capacity of the Nb2O5/carbon fiber sample obtained after hydrothermal treatment at 160°C for 14 hr. The maximal Cr(VI) adsorption capacity of the Nb2O5 nanowire/CF sample was 115 mg/g. This Nb2O5/CF sample also showed excellent photocatalytic activity and stability for the reduction of Cr(VI) under UV-light irradiation: the Cr(VI) removal efficiency reached 99.9% after UV-light irradiation for 1 hr and there was no significant decrease in photocatalytic performance after the use of the sample for 10 repeated cycles. Such excellent Cr(VI) adsorption capacity and photocatalytic performance was related to its high surface area, abundant surface hydroxyl groups, and good UV-light absorption ability. 相似文献
717.
Ehssan Torabi Charline Wiegert Benoît Guyot Stéphane Vuilleumier Gwenaël Imfeld 《环境科学学报(英文版)》2020,32(6):163-175
The soil dissipation of the widely used herbicides S-metolachlor(SM) and butachlor(BUT)was evaluated in laboratory microcosms at two environmentally relevant doses(15 and 150 μg/g) and for two agricultural soils(crop and paddy).Over 80% of SM and BUT were dissipated within 60 and 30 days,respectively,except in experiments with crop soil at 150 μg/g.Based on compound-specific isotope analysis(CSIA) and observed dissipation,biodegradation was the main process responsible for the observed decrease of SM and BUT in the paddy soil.For SM,biodegradation dominated over other dissipation processes,with changes of carbon isotope ratios(Δδ~(13)C) of up to 6.5‰ after 60 days,and concomitant production of ethane sulfonic acid(ESA) and oxanilic acid(OXA) transformation products.In crop soil experiments,biodegradation of SM occurred to a lesser extent than in paddy soil,and sorption was the main driver of apparent BUT dissipation.Sequencing of the 16 S rRNA gene showed that soil type and duration of herbicide exposure were the main determinants of bacterial community variation.In contrast,herbicide identity and spiking dose had no significant effect.In paddy soil experiments,a high(4:1,V/V) ESA to OXA ratio for SM was observed,and phylotypes assigned to anaerobic Clostridiales and sulfur reducers such as Desulfuromonadales and Syntrophobacterales were dominant for both herbicides.Crop soil microcosms,in contrast,were associated with a reverse,low(1:3,V/V)ratio of ESA to OXA for SM,and Alphaproteobacteria,Actinobacteria,and Bacillales dominated regardless of the herbicide.Our results emphasize the variability in the extent and modes of SM and BUT dissipation in agricultural soils,and in associated changes in bacterial communities. 相似文献
718.
Mapping and Modeling the Biogeochemical Cycling of Turf Grasses in the United States 总被引:6,自引:0,他引:6
Milesi C Running SW Elvidge CD Dietz JB Tuttle BT Nemani RR 《Environmental management》2005,36(3):426-438
Turf grasses are ubiquitous in the urban landscape of the United States and are often associated with various types of environmental
impacts, especially on water resources, yet there have been limited efforts to quantify their total surface and ecosystem
functioning, such as their total impact on the continental water budget and potential net ecosystem exchange (NEE). In this
study, relating turf grass area to an estimate of fractional impervious surface area, it was calculated that potentially 163,800
km2 (± 35,850 km2) of land are cultivated with turf grasses in the continental United States, an area three times larger than that of any irrigated
crop. Using the Biome-BGC ecosystem process model, the growth of warm-season and cool-season turf grasses was modeled at a
number of sites across the 48 conterminous states under different management scenarios, simulating potential carbon and water
fluxes as if the entire turf surface was to be managed like a well-maintained lawn. The results indicate that well-watered
and fertilized turf grasses act as a carbon sink. The potential NEE that could derive from the total surface potentially under
turf (up to 17 Tg C/yr with the simulated scenarios) would require up to 695 to 900 liters of water per person per day, depending
on the modeled water irrigation practices, suggesting that outdoor water conservation practices such as xeriscaping and irrigation
with recycled waste-water may need to be extended as many municipalities continue to face increasing pressures on freshwater. 相似文献
719.
Craig Doremus Donald C. McNaught Phillip Cross Ted Fuist Edith Stanley Barbara Youngberg 《Environmental management》1978,2(3):245-248
Carbon cycling analysis is presented as a means for assessing anthropogenic perturbations in an ecosystem. Data from oligotrophic, eutrophic, and dystrophic (bog) lakes are used to show general trends in the lacustrine carbon cycle. The oligotrophic lake is an unstressed system and the eutrophic lake is under nutrient enrichment with high algal standing crops and productivity. The bog lake is a pH-stressed environment that is primarily a grazing ecosystem. It is hoped that a more effective environmental impact assessment will result from the use of carbon cycling as a unifying concept in ecosystem analysis. 相似文献
720.
N. H. Ravindranath I. K. Murthy R. K. Chaturvedi K. Andrasko J. A. Sathaye 《Mitigation and Adaptation Strategies for Global Change》2007,12(6):1027-1050
Carbon forestry mitigation potential estimates at the global-level are limited by the absence or simplicity of national-level
estimates, and similarly national-level estimates are limited by absence of regional-level estimates. The present study aims
to estimate the mitigation potential for a large diverse country such as India, based on the GTAP global land classification
system of agro-ecological zones (AEZs), as well the Indian AEZ system. The study also estimates the implications of carbon
price incentive (US$50 and $100) on mitigation potential in the short-, medium- and long-term, since afforestation and reforestation
(A & R) is constrained by lack of investment and financial incentives. The mitigation potential for short and long rotation
plantations and natural regeneration was estimated using the GCOMAP global forest model for two land area scenarios. One scenario
included only wastelands (29 Mha), and the second enhanced area scenario, included wastelands plus long fallow and marginal
croplands (54 Mha). Under the $100 carbon price case, significant additional area (3.6 Mha under the wasteland scenario and
6.4 Mha under the enhanced area scenario) and carbon mitigation is gained in the short-term (2025) compared to the baseline
when using the GTAP land classification system. The area brought under A & R increases by 85–100% for the $100 carbon price
compared to $50 carbon price in the short-term, indicating the effectiveness of higher carbon price incentives, especially
in the short-term.
A comparison of estimates of mitigation potential using GTAP and Indian AEZ land classification systems showed that in the
short-term, 35% additional C-stock gain is achieved in the $100 carbon price case in the enhanced area scenario of the Indian
AEZ system. This difference highlights the role of the land classification system adopted in estimation of aggregate mitigation
potential estimates, particularly in the short-term. Uncertainty involved in the estimates of national-level mitigation potential
needs to be reduced, by generating reliable estimates of carbon stock gain and losses, and cost and benefit data, for land
use sector mitigation options at a scale disaggregated enough to be relevant for national mitigation planning. 相似文献