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641.
采用湍流循环燃烧炉芯板技术和燃煤锅炉自动监测控制技术,对现有中小型燃煤锅炉进行节能技术改造,可以有效提高锅炉热效率,降低锅炉煤耗和电耗,减少锅炉的大气污染物排放量,达到节能、降耗、减污、增效的经济和环境综合效益。  相似文献   
642.
低碳经济下的城市交通建设不仅要求建设足够的城市交通设施以满足居民对城市机动化的需求,同时必须发展与城市碳容系统相协调的交通体系以保持经济增长与环境需求间的动态平衡。因此中国在加快城市机动化推进的同时也面,陆着资源与环境问题的挑战。论文对中国如何发展城市交通低碳化进行了战略构想,从空间性减碳、技术性减碳和社会性减碳三方面着眼提出了可行性建议。  相似文献   
643.
A field lysimeter/mini plot experiment was established in a silt loam soil near Lincoln, New Zealand, to investigate the effectiveness of urea fertilizer in fine particle application (FPA), with or without the urease inhibitor N-(n-butyl) thiophosphoric triamide (NBPT - “Agrotain”), in decreasing nitrogen (N) losses and improving N uptake efficiency. The five treatments were: control (no N) and 15N-labelled urea, with or without NBPT, applied to lysimeters or mini plots (unlabelled urea), either in granular form to the soil surface or in FPA form (through a spray) at a rate equivalent to 100 kg N ha−1. Gaseous emissions of ammonia (NH3) and nitrous oxide (N2O), nitrate (NO3) leaching, herbage dry-matter (DM) production, N-response efficiency, total N uptake and total recovery of applied 15N in the plant and soil varied with urea application method and with addition of NBPT. Urea with NBPT, applied in granular or FPA form, was more effective than in application without NBPT: N2O emissions were reduced by 7-12%, NH3 emissions by 65-69% and NO3 leaching losses by 36-55% compared with granular urea. Urea alone and with NBPT, applied in FPA form increased herbage DM production by 27% and 38%, respectively. The N response efficiency increased from 10 kg DM kg−1 of applied N with granular urea to 19 kg DM kg−1 with FPA urea and to 23 kg DM kg−1 with FPA urea plus NBPT. Urea applied in FPA form resulted in significantly (P < 0.05) higher 15N recovery in the shoots compared with granular treatments and this was improved further when urea in FPA form was applied with NBPT. These results suggest that applying urea with NBPT in FPA form has potential as a management tool in mitigating N losses, improving N-response efficiency and increasing herbage DM production in intensive grassland systems.  相似文献   
644.
Pressure on consumer goods manufacturers to develop new products with significantly less environmental impact is growing, through increased consumer awareness of environmental issues and governments setting ambitious emissions reductions targets. A strategic response to this pressure is to prepare a portfolio of innovative product ideas to meet a range of future emissions reductions targets. However, although extensive work exists on ideation (the generation of novel product ideas) and eco-design (design for reduced environmental impact), eco-ideation (generation of ideas that particularly aim to reduce environmental impacts) has had little attention. The challenge of eco-ideation is to release the creativity of a broad range of employees, only few of whom may be familiar with the drivers of environmental impact.This paper proposes a novel tool to facilitate the generation of radical product and process ideas giving step-change reductions in greenhouse gas emissions. The features of products and processes that drive greenhouse gas emissions across the product life cycle were characterized with a set of indicators. A simple visual tool was created to show these indicators on a sliding scale between best and worst imaginable performance. A leading question associated with each slider was designed to stimulate lower impact ideas. The tool was iteratively refined and simplified through structured testing with individuals from across a range of roles and differing knowledge of environmental impacts. The final eco-ideation tool used 14 scales, with leading questions for each scale developed to stimulate idea generation.The tool’s effectiveness was evaluated through use in a series of 15 individual workshops and compared with the outcomes of an equal number of conventional 12-person group-brainstorming sessions. The comparison suggests that using the simple tool generally leads to a wider range of more radical ideas than emerge from group brainstorming.  相似文献   
645.
以中国环境标志建筑、建材标准为研究对象,介绍了中国环境标志的定义及其标准遵循的原则,介绍了环境保护部发布的环境标志标准HJ/T351-2007《生态住宅(住区)》、HJ/T296-2006《卫生陶瓷》、HJ/T297-2006《陶瓷砖》和HJ/T412-2007《预拌混凝土》的主要内容,分析了实施上述标准对建筑、建材行业节能减排的促进作用。  相似文献   
646.
There is substantial uncertainty regarding baseline greenhouse gas (GHG) emissions forecasts—i.e., how GHG emissions will grow over time in the absence of policy intervention. Thus baseline uncertainty should be a key consideration in setting GHG emissions targets as a mitigation strategy to respond to global climate change. At a minimum, the emissions target must be less than the baseline level to induce changing behavior and new investment. Despite this fundamental policy criterion, baseline considerations have played only a minor role in target setting under international climate policy. Baseline uncertainty applies to both absolute and intensity based emissions targets. It is demonstrated that one advantage of intensity targets is reduced uncertainty in the projected baseline, however there will always be some residual uncertainty in model projections. To illustrate the importance of considering baseline uncertainty in GHG target setting, the Bush Climate Change Initiative is analyzed against its projected baseline as a case study of a modest intensity target. Based on comparison with historical data, the range of projections by major energy-economic models, past discrepancies in the accuracy of model projections and the added complexity of sector-specific drivers for non-CO2 GHGs, it is shown that the Bush Initiative cannot be guaranteed or even expected to deliver actual reductions against an uncertain baseline. This finding emphasizes the importance of setting a target that accounts for baseline uncertainty to achieve genuine mitigation of GHG emissions.
Neil StrachanEmail:
  相似文献   
647.
利用美国橡树岭国家实验室二氧化碳信息分析中心公布的我国碳排放数据和各省的化石能源消费及水泥产量数据,对1980-2011年我国碳排放时空分布规律进行了研究.结果表明:全国及各省碳排放量呈现明显的阶段分布特征;各省碳排放量的区域差异呈现“高—低—高—低”的变化趋势;地均碳排放强度存在以低值集聚为主的正的空间自相关性,集聚趋势不断变化且在2006年后逐渐稳定;在0.05的显著性水平下,地均碳排放强度最终呈现北京、江苏和浙江的显著性“高—高”区,甘肃、青海、四川、新疆、宁夏和云南的显著性“低—低”区及大量不显著区稳定分布的特点.  相似文献   
648.
Objective: The purpose of this study was to investigate the effects of abuse conditions, including realistic crash scenarios, on Li ion battery systems in E-vehicles in order to develop safe practices and priorities when responding to accidents involving E-vehicles.

Method: External fire tests using a single burning item equipment were performed on commercial Li ion battery cells and battery packs for electric vehicle (E-vehicle) application. The 2 most common battery cell technologies were tested: Lithium iron phosphate (LFP) and mixed transition metal oxide (lithium nickel manganese cobalt oxide, NMC) cathodes against graphite anodes, respectively. The cell types investigated were “pouch” cells, with similar physical dimensions, but the NMC cells have double the electric capacity of the LFP cells due to the higher energy density of the NMC chemistry, 7 and 14 Ah, respectively.

Heat release rate (HRR) data and concentrations of toxic gases were acquired by oxygen consumption calorimetry and Fourier transform infrared spectroscopy (FTIR), respectively.

Results: The test results indicate that the state of charge (SOC) affects the HRR as well as the amount of toxic hydrogen fluoride (HF) gas formed during combustion. A larger number of cells increases the amount of HF formed per cell. There are significant differences in response to the fire exposure between the NMC and LFP cells in this study. The LFP cells generate a lot more HF per cell, but the overall reactivity of the NMC cells is higher. However, the total energy released by both batteries during combustion was independent of SOC, which indicates that the electric energy content of the test object contributes to the activation energy of the thermal and heat release process, whereas the chemical energy stored in the materials is the main source of thermal energy in the batteries.

Conclusions: The results imply that it is difficult to draw conclusions about higher order system behavior with respect to HF emissions based on data from tests on single cells or small assemblies of cells. This applies to energy release rates as well. The present data show that mass and shielding effects between cells in multicell assemblies affect the propagation of a thermal event.  相似文献   
649.
本文运用协整和Granger因果检验方法,实证了在1995-2013年间浙江省碳排放与经济增长、能源效率、对外贸易、城市化和人口增长的现实关系。研究表明:浙江省碳排放与经济增长之间呈现"弱脱钩"关系,对外贸易、经济增长和人口增长对碳排放有正向驱动效应,而能源效率和城市化水平对碳排放有负向驱动效应。Granger因果关系上,对外贸易、经济增长、城市化水平和人口增长是引起浙江省碳排放变化的Granger原因,且仅存在单向影响机制,能源效率与碳排放互为Granger因果关系。  相似文献   
650.
Surface water methane(CH4) and nitrous oxide(N2O) concentrations and fluxes were investigated in two subtropical coastal embayments(Bramble Bay and Deception Bay,which are part of the greater Moreton Bay, Australia). Measurements were done at 23 stations in seven campaigns covering different seasons during 2010–2012. Water–air fluxes were estimated using the Thin Boundary Layer approach with a combination of wind and currents-based models for the estimation of the gas transfer velocities. The two bays were strong sources of both CH4 and N2O with no significant differences in the degree of saturation of both gases between them during all measurement campaigns. Both CH4 and N2O concentrations had strong temporal but minimal spatial variability in both bays.During the seven seasons, CH4 varied between 500% and 4000% saturation while N2O varied between 128 and 255% in the two bays. Average seasonal CH4 fluxes for the two bays varied between 0.5 ± 0.2 and 6.0 ± 1.5 mg CH24/(m·day) while N2 O varied between 0.4 ± 0.1 and1.6 ± 0.6 mg N2O/(m2·day). Weighted emissions(t CO2-e) were 63%–90% N2 O dominated implying that a reduction in N2 O inputs and/or nitrogen availability in the bays may significantly reduce the bays' greenhouse gas(GHG) budget. Emissions data for tropical and subtropical systems is still scarce. This work found subtropical bays to be significant aquatic sources of both CH4 and N2O and puts the estimated fluxes into the global context with measurements done from other climatic regions.  相似文献   
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