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491.
峨边县土壤环境质量现状与优质安全农产品基地建设浅析   总被引:1,自引:1,他引:0  
付宪 《四川环境》2005,24(3):38-40
通过对峨边县几种主要农业土壤中重金属含量的监测和结果评价,分析出了峨边县土壤环境质量的现状,为峨边县发展无公害农产品和绿色食品生产基地提出建议。  相似文献   
492.
The paper aims to explore the implementation of an eco-design methodology and the related software platform (G.EN.ESI – Green ENgineering dESIgn) within technical departments of a manufacturing firm. The G.EN.ESI eco-design methodology is based on the life cycle thinking concept and the software platform is conceived as a set of inter-operable software tools able to efficiently exchange data among them and with the traditional design systems (i.e. CAD, PDM and PLM). A multinational company, designing and producing household appliances, adopted the proposed methodology and related software platform for redesigning two cooker hood models with the aim to improve their environmental performances. Design and engineering departments evaluated the methodology and platform impact on the product development process, as well as the platform inter-operability with traditional design tools. The results indicate that methodology and software platform satisfy the requirements of the enterprise in terms of: (i) degree of expertise and training requirement on this subject, (ii) low impact in a consolidated design process and, (ii) good level of inter-operability among heterogeneous tools. However, the testing results highlight the necessity of a further platform optimisations in terms of software integration (single workbench made by integrated software tools with the same graphical user interface).  相似文献   
493.
电催化还原CO2转化为清洁能源或有用的化学品被认为是减排CO2的一种有效方式。金属有机框架(MOFs)材料由于分散的金属中心和可调的化学结构等特点而被广泛应用于电催化领域。综述了MOFs材料用于电催化还原CO2的研究进展,对比了近年来MOFs材料及其衍生物电催化CO2化学转化的效率及产物选择性,并对MOFs材料作为电催化材料的应用前景进行了展望。  相似文献   
494.
元素硫高温腐蚀产物氧化自燃性影响因素的研究   总被引:1,自引:1,他引:0  
用差热-热重分析仪考察元素硫与Fe(OH)3发生硫化腐蚀反应的初始温度,分析硫化温度、硫化时间、氧化温度和水对高温硫腐蚀产物氧化自燃性的影响。结果表明:元素硫与Fe(OH)3发生硫化反应的初始温度为287.67℃;硫化温度越高,硫化时间越长,元素硫高温硫化腐蚀产物中FeS2的含量越高,氧化自燃性越大;氧化温度对高温硫腐蚀产物的氧化自燃性有很大影响,室温时几乎不发生氧化反应,氧化温度超过95℃后,腐蚀产物的氧化反应速率大幅度提高,对炼油装置安全构成极大威胁;水对高温硫腐蚀产物的氧化自燃性起着重要作用,无水时,高温硫化产物基本不发生氧化反应,少量水存在即可极大影响高温硫腐蚀产物的氧化速率。  相似文献   
495.
Meaningful human–nature interactions can counteract the extinction of experience and positively influence people’s nature relatedness, health and wellbeing. In this study, we explored urban wild food foraging to understand how best to enable human-nature interactions in cities by means of foraging. Using a structured questionnaire, a total of 458 residents of Vienna, Austria were surveyed. Sixty-four percent of visitors of public urban green spaces previously foraged for wild food species, whereas foraging frequencies were related to the targeted plant species and their life forms. People who foraged more frequently had greater nature relatedness, more childhood foraging experiences and lived on the outskirts of the city, but their socio-demographic backgrounds were heterogeneous. Social acceptance and lack of access to wild foods were perceived to be barriers. To promote nature relatedness through urban foraging, the legal framework, access to low-contamination foraging areas, availability of wild foods and social acceptance need to be improved.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01648-1.  相似文献   
496.
A feasible and relatively readily available analytical method was adapted for the assessment of alcohol ethoxylates (AE) and fatty alcohols (FA) in sediments. This study illustrates the simultaneous measurement of 38 of 114 possible alcohol ethoxylate ethoxymers (AE) and fatty alcohols (FA) found in commercially important AE products. We predicted toxicity for all identified fractions, as well as the total mixture toxicity, relative to three exposure scenarios via sewage treatment plants (STP) for these widely used chemicals in consumer products and hence generate a preliminary environmental risk screening for AE and FA in sediments. The method is based on derivatization of solvent or solid-phase extracts with 2-fluoro-N-methylpyridinium p-toluenesulfonate (Pyr+). The derivatized extracts were analyzed with liquid chromatography/mass spectrometry (LC/MS) operating in the positive ion electrospray mode. The extraction efficiency of AE and FA in three different sediments of varying composition was evaluated with spike-recovery studies, ranging from 64% to 80%. The detection limits for individual ethoxymers typically ranged from 1 to 5ngg−1on a dry weight basis. The mean limit of detection (LOD) was 6ngg−1and the median LOD was 3ngg−1. AE and FA in sediments were found to be stable for two weeks if preserved with 3% (v/v) formalin and stored at 4–6C. Based on equilibrium partitioning, background concentrations of AE and FA were predicted to be below concentrations known to elicit chronically toxic effects. Total worst case mixture toxicities for all AE ethoxymers combined with FA were predicted to result in a risk quotient less than 0.6. Activated sludge treatment (STP) significantly reduced the release of total AE and FA by four-fold, suggesting that the total mixture risk quotient would be < 0.15 for sediment dependent organisms.  相似文献   
497.
生态产品价值实现是推动绿水青山转化为金山银山、促进人与自然和谐共生的关键路径和有效举措,对加快生态文明建设具有重要意义。本文根据生态产品的产权界限、公益性程度和供给消费方式,系统梳理了不同类型的生态产品价值实现模式,深入剖析了当下生态产品价值实现的制约瓶颈,如产权界定不清、法律制度不完善、市场机制不健全、生态补偿机制和保障体系有待进一步优化等。在此基础上,研究提出完善生态产品价值实现的针对性对策建议:(1)完善生态产品产权体系,夯实“绿水青山”向“金山银山”转化的制度基础;(2)培育生态产品市场建设,拓宽“绿水青山”向“金山银山”转化的市场化通道;(3)健全生态补偿机制,优化多主体利益联结机制;(4)强化生态产品价值实现保障体系,提升生态产品转化成效。  相似文献   
498.
结合型号可靠性试验工作。阐述了光电产品可靠性试验的特点及其故障判据。针对光学器件和光电产品的特点,以光电显示系统、瞄准具及热像仪等产品为例。对光电产品在可靠性试验过程中发生的故障模式、故障机理和故障原因进行了分析。  相似文献   
499.
通过在一维煤粉燃烧炉上进行无烟煤添加高岭土吸附剂的燃烧实验,研究了无烟煤及其燃烧产物中18种环境有害微量元素的含量和分布;计算了高岭土在不同燃烧工况条件下对每种环境有害微量元素的吸附率.结果表明,高岭土对环境有害微量元素Cd, Pb, Sb, Sn, Ba, Co, Be, Cr, Ni, Mo, Tl, V, U, Mn, Th具有不同的吸附作用,吸附率为11.6%~500%;吸附效率与元素种类、燃烧工况等因素有关,环境有害微量元素Cd, Pb, Zn, Sb, Ba, Co, Be, Cr, Ni, Mo, Tl, V, U, Mn, Th的吸附能力,分级燃烧比不分级燃烧吸附效果更好,总吸附率差为8.4%~481%.  相似文献   
500.
In recognition of the many values that people ascribe to nature, federal, provincial, and territorial agencies worked inpartnership to complete the 'Survey on the Importance of Natureto Canadians' (SINC) in 1981, 1987, 1991, and 1996. Between 1981 and 1996, more than 80% of Canadians 15 years of age and older engaged in one or more nature-related activities. This paper describes the evolution of this cooperative monitoring program, defines a classification system as a context for the values examined by the SINC, highlights trends of some nature-related recreational activities measured by the survey, and comments onthe importance of this information to Canadians.  相似文献   
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