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1.
目的将3种高分子材料以及3种车用外饰材料分别投放在中国海南琼海和美国佛罗里达州2种典型湿热环境中进行户外曝晒试验,研究气候相似的2种地区的试验相关性。方法通过测试相同时间间隔下不同材料在2处试验场曝晒过程中的黄变程度,表征材料的老化现象。采用斯皮尔曼等级相关系数的统计方法,研究材料在2个地区相同时间节点的试验结果的相关性,并利用时间同轴的作图方法比较2个地区严酷度的差异。结果琼海与佛罗里达州2个地区在各个时间节点的相关系数接近于1,且在材料黄变方面呈现一定比例关系。结论琼海和佛罗里达州2个地区的试验结果呈现出较好的相关性,且严酷度比值约为琼海︰佛罗里达=1︰1.19。  相似文献   

2.
目的研究面向典型高分子材料应用的大气环境严酷度分类方法。方法开展聚苯乙烯在我国10个典型大气环境地区的自然暴露试验,对比分析聚苯乙烯表面及力学性能的变化规律及差异,确定大气环境严酷度评估参数,依据评估参数量值对大气环境严酷度分类分级。结果聚苯乙烯表面的黄色指数随时间呈线性增大,且各环境地区的规律一致,其老化模型中的常数可作为大气环境严酷度评估的性能参数。太阳辐射和高温高湿是影响聚苯乙烯劣化的主要环境因素。结论以聚苯乙烯性能为大气环境严酷度评估参数,可将我国大气环境严酷度划分为6个等级。  相似文献   

3.
大气环境腐蚀性分类分级研究综述   总被引:4,自引:2,他引:2  
介绍了大气环境腐蚀性分类分级的发展状况、方法和作用,归纳了现有大气环境腐蚀性分类分级方法在等级划分、影响因素等方面存在的不足,展望了大气环境腐蚀性分类分级研究的发展趋势,并指出了开展针对高分子材料的大气环境老化严酷度分类分级研究的重要意义。  相似文献   

4.
分析了线缆材料在拉萨自然环境试验站中1~2年的短周期试验性能变化。线缆高分子材料在土壤环境中性能变化较小,而在大气环境中力学性能有所下降,HDPE耐环境性能、应力开裂性能下降26%;金属在土壤环境中腐蚀较轻。拉萨大气与土壤自然环境对材料的短期腐蚀(老化)作用比较轻微。  相似文献   

5.
目的 探究我国典型湿热海洋大气环境特征,以Q235钢为标杆材料,评估并可视化展示海南湿热海洋大气环境严酷度。方法 以海南岛为典型湿热海洋地区,基于分布全岛全域的13个站点开展自然大气环境试验,采集各站点大气环境数据与Q235钢材料性能数据。通过分析表观形貌、腐蚀质量损失等性能,探究Q235钢在海南大气环境的腐蚀行为规律及其在全岛不同区域的腐蚀程度差异。基于大气环境因素与Q235钢腐蚀行为间相关性研究,筛选腐蚀敏感环境因素,构建“腐蚀质量损失-敏感环境因素”映射模型。基于Q235钢海南各地区腐蚀质量损失数据,通过Griddata插值,计算绘制腐蚀质量损失分布地图。结果 掌握了Q235钢在海南各地区腐蚀行为差异,可视化展示了海南大气腐蚀严酷度。结论 影响Q235钢海南地区腐蚀的敏感环境因素为离海距离及湿度大于80%的时间。海南地区沿海岸及东部地区大气环境腐蚀严酷度高,中部及西部地区严酷度低。  相似文献   

6.
目的 建立大气环境干热、干冷环境特征的表征方法,以便定量表征大气环境干热、干冷的严酷性,为高分子材料及产品在该地区的老化试验与评估提供参考。方法 设置温度-相对湿度组合为临界值,统计给定时期内温度高于临界温度、相对湿度低于临界相对湿度的时间为干热时间,统计给定时间内温度低于临界温度、相对湿度低于临界相对湿度的时间为干冷时间,并以干热时间、干冷时间占给定时期总时间的百分比来表征干热、干冷环境特征,研究临界条件、数据间隔时间对干热、干冷特征的影响。结果 以25 ℃RH40%、5 ℃ RH40%为临界条件分别统计干热时间和干冷时间的月、年百分比,可表征大气环境的干热、干冷特征。敦煌6、7月份为干热严酷月,月干热时间百分比超过40%,1、2月份为干冷严酷月,月干冷时间百分比可超过70%。结论 临界温度、临界相对湿度、统计年份、数据间隔时间等对统计结果有较大的影响。  相似文献   

7.
目的研究海洋大气、干热沙漠、寒冷低温和高原低气压四种典型大气环境对7050高强铝合金腐蚀行为的影响。方法通过在万宁、敦煌、漠河、拉萨四种典型环境中开展7050高强铝合金大气暴露试验,利用腐蚀质量损失、力学性能、腐蚀形貌、金相显微分析7050高强铝合金在我国四种典型大气环境中的腐蚀规律和行为。结果暴露1年,海洋大气环境对7050高强铝合金的腐蚀质量损失、力学性能、腐蚀形貌和金相显微组织有明显影响,干热沙漠环境对铝合金的腐蚀形貌和金相显微组织有一定影响,铝合金对寒冷低温和高原低气压大气环境腐蚀不敏感。结论四种典型大气环境对7050高强铝合金腐蚀影响大小的顺序为万宁>敦煌>漠河和拉萨。  相似文献   

8.
改进的灰色识别法以灰色关联法为基础,针对灰色关联法评价大气环境质量的不足,引入关联离散度和隶属度算法加以改进,并将大气环境质量标准等级就其相应的隶属度加权平均求得更为精确的大气环境质量级别,提高了分辨率和实用性。在简要论述利用改进的灰色识别法评价大气环境质量的计算原理、方法和步骤的基础上,以北京市石景山区为研究对象,对大气环境质量进行评价,确定质量等级及其变化趋势,为大气环境保护规划提供科学依据。结果表明:改进的灰色识别法可比性强,分辨率高,具有较高的实用价值。  相似文献   

9.
以鄱阳湖流域代表性城市南昌市为研究对象,构建城市化与大气环境综合评价指标体系,并利用耦合协调度模型定量分析2002—2016年南昌市城市化与大气环境的综合发展水平和两者之间的耦合协调关系及其演变趋势。结果表明:社会城市化和大气环境状态分别对城市化系统和大气环境系统的贡献份额最大,城市化综合发展水平呈现持续上升的趋势,大气环境综合发展水平呈现波动上升的趋势,城市化对大气环境的影响以压力为主,大气环境响应不足;在耦合协调度测算模型中,耦合协调度受城市化系统与大气环境系统不同贡献份额比例(α/β)的影响很小;城市化与大气环境耦合协调度整体呈现上升的趋势,耦合协调类型由"严重不协调-城市化受阻"发展到"高度协调-大气环境滞后"阶段,耦合协调关系整体趋向较好的方向发展,大气环境滞后程度却日趋严重。因此,在制定城市发展战略时要更加注重大气环境的保护,以推动南昌市城市化与大气环境协调的可持续发展。  相似文献   

10.
目的分析我国沿海地区大气环境特征,研究典型沿海地区大气腐蚀性。方法根据近50年历史气象数据以及实测介质数据,分析我国沿海地区的气温、湿度、太阳辐射、盐雾等主要环境因素的分布规律,并结合主要环境因素与腐蚀数据对典型沿海地区大气腐蚀性进行比较。结果给出了我国沿海地区主要大气环境因素的量值范围,以及典型沿海地区大气腐蚀严酷度等级。结论我国沿海地区大气环境特征南北差异较大。大部分地区的大气腐蚀性等级为C3级或C4级,极个别海岸地区及海洋平台可达到C5级。  相似文献   

11.
不同环境材料对Pb、Cd污染土壤的淋溶效应   总被引:9,自引:1,他引:8  
为了探索环境材料对土壤中重金属的去除效果,采用土柱淋溶方法研究了不同环境材料(腐植酸HA、高分子材料SAP、粉煤灰FM及沸石FS)对污染土壤(单一Pb污染土壤、单一Cd污染土壤和Pb-Cd复合污染土壤)中铅(Pb)、镉(Cd)的淋溶效应。结果表明:添加不同环境材料处理的淋出液pH值呈现先上升后降低再上升的趋势,均为弱碱性。添加FM和复合N1(HA+SAP+FM+FS)、N2(HA+SAP+FM)处理淋出液的电导率(EC)明显高于其他。FM和复合N1、N2对单一Pb污染土壤中Pb达到显著固定作用;单一Cd污染土壤中,添加单一SAP处理所淋溶出的Cd量小于CK(未加任何环境材料),淋溶出的Cd量为CK的63.68%,对Cd起到一定的固定作用;Pd-Cd复合污染土壤中,HA对Pb达到显著固定作用,淋出Pb量仅为CK的40.6%。SAP及复合N3对Cd的固定作用明显,淋溶出的Cd量分别为CK的55.32%、78.13%。可见,采用的环境材料对重金属淋溶能起到一定的抑制作用。  相似文献   

12.
Life cycle thinking is emphasised in EU policies and legislation. All products have environmental impacts during their production, use and disposal. It is important to ensure that environmental impacts are considered throughout the life-cycle and it will be more and more important for the industry to understand the meaning of the life cycle thinking and to adopt it.The environmental impacts of an industrial disposable cup concept were studied with help of life-cycle assessment method. The objective of the study was to create new knowledge about the life cycle effects of the carton based cup concept. The scope of the study was to compare the effects of material choices and different end-of-life scenarios. The paper focuses on the global warming potential of the cup concept. The carton based products were covered either with polyethene or polylactide. In addition, the environmental impacts of the carton-based cups were compared to the estimated environmental impacts of polymer-based cups. The polymer based cups were made of polyethylene terephthalate. The paper shows that significant improvements can be achieved with help of the choice of materials and optimal end of life.  相似文献   

13.
This paper focuses on investigating several aspects of the machining process from an ecological perspective, the result being a macro-level analysis. The analysis presented here considers not only the environmental impact of the material removal process itself, but also the impact of the associated processes such as the material preparation, and the scrap processing. A macro-level assessment of the comparative life cycle environmental performance of the near-dry machining (NDM) using TiN-coated carbide tools and the flood machining (FM) is performed by a case study referring to the gear milling. The assessment, using the SimaPro 7.1.5 software and the ecoinvent1.5 database, includes combined Life Cycle Assessment (LCA) of the workpiece material, the scrap processing, the use of lubrication, and the energy consumption.  相似文献   

14.
Single-use medical devices have been under close scrutiny for several years, especially the choice of plastic materials. Many different requirements such as medical safety, treatment functionality and efficiency, environmental performance, etc. have to be fulfilled. Today, the most commonly used materials for hydrophilic urinary catheters are polyvinylchloride (PVC) and thermoplastic polyurethane (TPU). In this research study, these two materials' environmental performance was evaluated. In light of the knowledge gained in that study a new plastic material for use in urinary catheters was developed. The aim of the development of this new material was to design a high performance material with superior environmental performance. The newly developed plastic material is a polyolefin-based elastomer. The ecological environmental performance of the new material was evaluated and compared to the existing plastic materials. The study focused exclusively on the choice of plastic materials and their ecological environmental performance.The analysis has been performed using a system perspective and a life cycle assessment (LCA) methodology. The functional unit has been set to the treatment of one patient during one year. The results from the LCA models have been presented both in terms of direct inventory data, such as energy use and formed emissions, and in terms of the results from four different impact assessment methods. Analysis of the results based on direct inventory data, i.e. common inventory results such as energy resource uses and emissions of CO2, NOx and SO2 show an overall better environmental performance for the new polyolefin-based elastomer compared to the existing PVC and TPU plastic materials. The normalization and weighting steps in the analyzes have indicated the importance of energy resource uses and global warming as indicator for the environmental performance even if other impact categories also can play a role. In the environmental impact assessment, the polyolefin-based elastomer showed a clearly better environmental performance than the TPU material. Compared to PVC plastic material the new polyolefin-based elastomer showed an almost equivalent environmental performance. This can be mainly explained by the different materials' energy use. The new material has thus also shown to be an environmentally good alternative to PVC if a PVC-free material is requested. Basing the plastic formula, on simple bulk plastics with low energy use in the production of single-use medical devices, has been shown to be a successful method of producing high quality products with superior environmental performance.  相似文献   

15.
物质代谢研究进展综述   总被引:5,自引:0,他引:5  
传统的线性经济生活模式导致人类社会面临着巨大的环境压力,因此为提高资源的利用效率,实现社会经济的可持续发展,物质代谢研究逐渐成为近年来国际研究领域的热点问题。文章从三方面对国际上关于物质代谢研究进展做了阐述:①物质代谢的研究背景;②物质代谢的基础性研究,包括不同层次的物质代谢吞吐量的研究和物质代谢定量分析方法的探讨;③物质代谢相关的研究进展,包括土地利用/覆盖变化、自然环境效应和可持续发展与物质代谢作用关系的讨论。最后,对其未来的发展方向提出了一些建议,认为除了要进一步完善物质代谢研究方法和模型外,还应从土地利用/覆盖变化、研究尺度、政策和行为、生态环境效应等角度对物质代谢进行拓展分析。  相似文献   

16.
The relationship between economy and environmental impacts has been an essential topic in the discussion on environmental problems for a long time. From the 1990s, this relationship has gained a position in environmental policy as well. De-coupling the use of natural resources from economic growth has been set as one of the policy goals in the sixth Environmental Action Programme by the European Commission. In the scientific discussion, the concept of environmental Kuznets curve deals closely with the de-coupling or de-linking phenomenon. Aggregated material flows, on the other hand, have often been considered as a macro-level proxy of environmental degradation. Different methods or approaches have been designed for “sustainability” or “carrying capacity” evaluation as well. The objective of this article is (i) to discuss the possibilities and limitations of using environmental and economic indicators in the sustainability analysis at the macro level, (ii) to present a theoretical framework for the linking analysis including a classification of the degrees of de-linking/re-linking environmental impacts from/to economic growth, and (iii) to give an empirical example by using indicators of direct material flows as a proxy of environmental degradation and by applying the framework into the European Union and its 15 member countries. The results show that the trend in the European Union is a weak de-linking of material flows from economic growth during the years 1980–2000. In other words, material intensity of the economy has generally decreased due to increased efficiency, but the absolute amount of material use has increased, although at a lower rate of increase than economic growth. On the other hand, there is a quite large variation between different EU member countries. However, absolute decrease in the use of materials cannot be found as a continuous trend between the years 1980 and 2000 in any of the studied EU member countries.  相似文献   

17.
从环境类学术文献看中国环境教育存在的问题   总被引:5,自引:0,他引:5  
根据我国环境科学类期刊上刊登的环境教育文献的比重和内容的调查结果来看,我国环境科学界对环境以重视程度与环境教育的重要性不成比例,环境教育研究的落后已成为制约我国环境教育可持续发展的关键问题。  相似文献   

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