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641.
夏季环境空气中臭氧和氮氧化物变化关系   总被引:7,自引:2,他引:7  
分析了宜昌市夏季高温日照天气下环境空气中臭氧和氮氧化物之间的变化趋势,研究了环境空气中光化学反应的时间和程度,提出了重视光化学反应污染和控制氮氧化物的一些建议。  相似文献   
642.
Many urban areas face conflicts between economic growth and environmental limitations. The ecological footprint is popular for communicating the global impacts of local activities, and if calculated at the local level, should be useful in emphasising the impacts of local planning, engaging community members, and allowing intra-community comparisons. We compare the two dominant methods for local ecological footprints: the compound and component methods. Both fail to adequately represent local footprints in North America. We propose a hybrid component method that takes advantage of the benefits of the component method but incorporates interpolation from the compound method to address data limitations. Grounded in Montreal, Canada, a city currently facing significant conflict between environment and growth, the study applies the hybrid method and discusses its potential benefits and limitations for community activists and planners.  相似文献   
643.
Despite several recent UK initiatives to promote renewable energy development at the local level, little research has been carried out to investigate public beliefs about aspects of local renewable energy development. This research attempted to address this gap. Empirical data were collected at the Awel Aman Tawe development in South Wales immediately before and after a public participation process. The results indicate that support for specific aspects of local energy development (partnership with local communities, local use of generated energy and profits put back into the local community) was consistently high across time, with support for local ownership at a slightly lower level, yet still high. Secondly, socio-demographical analyses indicated that personal factors such as respondents' age, gender and employment status were important in shaping several of these beliefs. Since UK renewable energy development has often been controversial and subject to delay, results suggest that the adoption of a locally embedded development approach by public and private sector stakeholders will be strongly supported by local people. The implications of the results are discussed in relation to existing industry best practice guidelines and recent policy initiatives.  相似文献   
644.
Abstract

A concept of occupational entropy is developed and related to the efficient use of mental (cognitive, emotional, and moral) resources and capacities. The corresponding “mind” indicators and pertinent response actions have proven essential for monitoring the state and projecting the behavior changes toward energy sustainability, as well as sustainable development in general.  相似文献   
645.
A strong increase in the demand for some commodities over the last decade will have a major impact on their future supply situation. Of increasing importance, therefore, is an assessment of a commodity's criticality, and especially its supply risk, by appropriate indicators. The literature has proposed numerous indicators of the supply risk. Here, we use the convenience yield of commodity futures as a supply risk indicator to address some of the major shortcomings of existing indicators, especially regarding their predictive power. This paper aims to test the applicability of the convenience yield as an indicator of a commodity's future supply risk. Therefore, we calculate historical convenience yields for 3-, 15-, and 27-month futures contracts for five major industrial metals (aluminum, copper, lead, nickel, and zinc) during the period 1999 to 2011. We compare the convenience yields at the beginning of the contract period to known indicators at maturity to find that the convenience yield has generally predictive power for the static stock lifetime (i.e., inventory volume/turnover) and future spot prices. Furthermore, we find that, with some restrictions, the convenience yield is an applicable indicator of a commodity's supply risk.  相似文献   
646.
垃圾渗滤液是一种复杂有毒的、生化降解性差的高浓度有机废水,高级氧化技术具有氧化能力强和无二次污染等特点,被认为是处理难降解有机污染物最有应用前景的方法.本研究在500 W汞灯、25℃、2.5 h反应条件下,对比了TiO_2、K2S2O_8、K2S2O_8/Fe2+、施氏矿物、施氏矿物/H2O_2、Fe2+/H2O_26种催化剂组合光化学处理垃圾渗滤液的效果.结果表明,施氏矿物/H2O_2和Fe2+/H2O_2光催化降解垃圾渗滤液中有机污染物的效果优于其它催化剂组合,渗滤液中CO_D去除率分别为41.6%和46.5%,TO_C去除率分别为76.0%和78.1%.然而,Fe2+/H2O_2组合在光催化处理垃圾渗滤液后会产生大量难以沉降的Fe(O_H)3絮状物,且渗滤液色度明显增加,由初始的40倍上升到175倍.而施氏矿物/H2O_2组合则避免了上述问题,色度去除率达100%,被认为是一种具有应用前景的光化学降解垃圾渗滤液的催化剂组合.  相似文献   
647.
华北农村夏季大气甲醛浓度变化特征   总被引:3,自引:1,他引:2       下载免费PDF全文
为研究华北农村大气污染状况,于2013年夏季和2014年夏季先后在华北两个农村站点——固城站、饶阳站,采用基于汉栖(Hantzsch)反应的在线甲醛荧光分析仪开展大气甲醛在线观测,结合同期φ(O3)、φ(PAN)(PAN为过氧乙酰硝酸酯)、φ(CO)和光解速率系数等数据,分析φ(甲醛)日变化及其光解速率等特征. 结果表明:华北农村夏季大气甲醛污染较重. 固城站和饶阳站φ(甲醛)分钟均值范围分别为0.05×10-9 ~59.18 ×10-9和1.66×10-9 ~ 46.83×10-9,平均值分别为12.82×10-9±7.59×10-9和13.73×10-9±5.82×10-9,高于文献报道的国内外其他地区的观测值,与同期观测的φ(NOx)相当. 两个站点φ(甲醛)具有典型的日变化特征,φ(甲醛)小时均值峰值(固城站为17.43×10-9,饶阳站为17.57×10-9)均出现在上午10:00左右,与φ(O3)和φ(PAN)的日变化趋势相似,但峰值早1 h出现. 光解速率系数观测结果表明,两个站点甲醛光解过程主要发生在06:00—18:00,固城站甲醛小时光解量峰值(2.59×10-9)出现在11:00,饶阳站甲醛小时光解量于正午12:00达到峰值(3.00×10-9),甲醛光解成稳定分子的速率是光解成自由基速率的1.2~1.7倍. 研究表明,两个站点φ(甲醛)的变化主要受局地过程的影响,光化学生成是甲醛的重要来源.   相似文献   
648.
The global agenda of sustainable development (SD) will get a major boost from the successful implementation of the Sustainable Development Goals (SDGs) in developing countries. This requires effective planning and understanding of the SDGs at the national level and developing sound SDG indicators that account for country priorities. Currently, there is no formal SDG indicator set in India, but the process for it is underway. This paper has attempted to propose a unique technique for identifying the most representative indicator set for SD measurement in India based on the SDGs. Considering the needs and preferences of the country, a three‐stage process is proposed to develop the priority indicator set. The application of the approach has been presented for SDG 7, which relates to energy. This is supported with a background on India's SD progress. The proposed technique is simple yet effective, and can be easily replicated by other developing countries.  相似文献   
649.
工艺安全绩效指标介绍   总被引:1,自引:0,他引:1  
介绍了根据瑞士奶酪模型——事故与保护层漏洞所设置的工艺安全绩效指标体系,探讨了美国石油学会标准的工艺安全绩效指标及分级,列举了每一级指标的具体指标和数据收集要求,并具体介绍了杜邦公司的工艺安全绩效指标体系,为国内企业提供参考。  相似文献   
650.
制药工业特别是生物制药是上海市六大支柱产业之一,而在制药生产过程中存在着原辅料投入量大产出比小、污染严重的问题。针对制药企业在生产中的原辅材料、工艺过程、产品环节中可能产生有毒有害有机物等进行了调研分析;对比国内外相关排放控制标准,提出了制药工业污废水排放中特征污染因子控制指标的建议。建议补充18种特征污染因子,其中包括1种重金属及无机物、16种有机污染物和1项生物安全因子。  相似文献   
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