自然气候老化测试及应用

描述自然气候条件对材料老化的影响以及对预测材料不同应用方向等方面的影响。通过对不同地点,不同老化方法的比较,重点介绍了目前国际上使用的老化方法－直接曝晒,黑板箱曝晒,间接曝晒,自然加速老化等多种标准方法的特点,使用的局限性以及对材料老化结果的影响,并详细介绍了适用于自然老化地点的选择,主要影响因素等等。文章在分析多种老化方法的同时,指出了各种方法的适用性,这对材料老化方面的研究有很大的参考价值和指导意义。     

聚苯乙烯材料的氙灯与海南自然老化的相关性和加速性研究

为考查聚苯乙烯材料(PS)的在人工和自然老化之间相关性和加速性,在海南湿热环境的5个站点开展自然暴露试验,基于色差变化数据,PS在琼海和临高的老化速率最大。通过开展3种不同条件的氙灯老化试验,比较自然和加速老化的相关性,选出最适合模拟海南湿热环境的氙灯试验条件。再对氙灯老化相对5个站点的自然老化的加速性进行了探讨,结果显示氙灯老化方法 1对海口自然老化的加速性最大,加速因子为7.87。     

材料和产品大气暴露与人工加速试验相关性的探讨意见(下)

应用人工加速气候与自然或实际大气暴露试验的实例,说明了研究两者相关性的可能性和实际应用意见,并概述高分子材料进行人工加速和湿热自然大气暴露的对比结果,分析探求人工加速气候与自然或实际大气暴露试验两者相关性的主要因素。     

材料和产品大气暴露与人工加速试验相关性的探讨意见(上)

应用人工加速气候与自然或实际大气暴露试验的实例,说明研究两者相关性的可能性和实际应用意义,并概述高分子材料进行人工加速和湿热自然大气暴露的对比结果,分析探求人工加速气候与自然或实际大气暴露试验两者相关性的主要因素。     

汽车内饰材料老化试验研究

本文介绍了汽车内饰材料常见的老化试验方法:人工加速老化试验、IP/DP箱暴晒和整车暴晒,分别讨论三种试验方法涉及的规范以及操作性.人工加速老化试验能快速掌握汽车内饰材料老化性能,缩短材料研发周期;IP/DP箱和整车对内饰件或其装配件进行的老化试验降低内饰材料加工工艺存在的风险,确保了内饰材料质量.整车暴晒收集的数据为人...     

基于薄弱环节的发动机加速贮存试验研究

对基于薄弱环节的发动机加速贮存试验的理论依据和发动机加速贮存试验的基本流程进行了介绍,在对发动机薄弱环节的确定方法和薄弱环节失效机理分析的基础上,提出了材料、部组件和整机层层递进的加速贮存试验方案和基于物理老化、化学老化和使用载荷验证的发动机加速贮存试验一体化设计方法.     

湿热、亚湿热地区气候环境条件对高分子材料的影响

通过高分子材料在广州、海南地区三年大气自然环境曝露试验与人工加速试验对比，探索该类地区气候环境条件对高分子材料老化的规律性的影响。     

橡胶材料自然环境老化失效研究进展

橡胶环境适应性评价方法正由单一环境因素向多因素协同作用研究发展;从自然大气试验方法向多因素模拟加速实验室试验研究发展。从橡胶的老化现象、老化机理、老化性能评价方法等对目前橡胶材料自然环境老化失效研究进展进行了介绍和分析。     

文摘

《户外用绝缘材料技术及应用》—《电气杂志OHM 》1989,76(3),44～49(日):叙述户外用绝缘材料概况、环境因素与老化作用、户外用高分子材料及适用的、户外用高分子材料及耐候性、户外高分子材料的加速试验方法及户外用绝缘材料的未来展望等.介绍加速试速试验装置的试验方法和结果以及与户外暴露试验的相关性.     

工业仪表对湿热环境的适应性

本文介绍部份仪表的零件及其材料的耐湿热性能、我国目前仪表的耐湿热性、湿热因素对仪表的影响、腐蚀机理的探讨和人工加速试验方法的选定.提出提高仪表质量的措施和鉴定的手段.本报告为热带仪表的可靠性分析和设计,提供了依据.     

回顾 总结 部署

3月26日至3月28日,备受关注的2003年度中国石油集团公司安全生产环境保护职业健康工作会议在青岛召开。 会议期间王海森主任做了题为“与时俱进,开拓创新,推进安全环境健康工作再上新水平”的报告,指出此次会议的主要任务是:总结回顾过去三年安全生产,环境保护和职业健康工作,分析形势,安排部署2003年工作,推进安全环境健康工作再上新水平。回顾三年的成绩,主要体现在:安全环保健康目标和责任制不断落实;安全环保健康规章制度逐步完善;安全环保机构得到加强和充实;健康安全环境管理体系全面推进;建设项目环境管理规范进行;安全环保科技创新…     

Sustainability,eco-efficiency,life-cycle management,and business strategy

This article outlines some of the rationale for integrating environment and sustainablility issues into core business practises and provides some guidance on how companies can begin to take a strategic view when selecting environmental management tools. Two of these tools, life cycle management and eco-efficiency, are outlined in brief.© 1999 Five Wind International. Reprinted with permission by John Wiley & Sons, Inc.     

Atrazine, isoproturon, mecoprop, 2,4-D, and bentazone adsorption onto iron oxides

Iron oxides are important components influencing the adsorption of various inorganic and organic compounds in soils and sediments. In this study the adsorption on iron oxides of nonionic and ionic pesticides was determined as a function of solution pH, ionic strength, and pesticide concentration. The investigated iron oxides included two-line ferrihydrite, goethite, and lepidocrocite. Selected pesticides comprised atrazine (6-chloro-N2-ethyl-N4-isopropyl-1,3,5-triazine-2,4-diamine), isoproturon [3-(4-isopropylphenyl)-1,1-dimethylurea)], mecoprop [(RS)-2-(4-chloro-2-methylphenoxy)propionic acid], 2,4-D (2,4-dichlorophenoxyacetic acid), and bentazone [3-isopropyl-1H-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide]. The adsorption of the nonionic pesticides (atrazine and isoproturon) was insignificant, whereas the adsorption of the acidic pesticides (mecoprop, 2,4-D, and bentazone) was significant on all investigated iron oxides. The adsorption capacity increased with decreasing pH, with maximum adsorption reached close to the pKa values. The addition of CaCl2 in concentrations from 0.0025 to 0.01 M caused the adsorption capacity to diminish. The adsorption of bentazone was significantly lower than the adsorption of mecoprop and 2,4-D, illustrating the importance of a carboxyl group in the pesticide structure. The adsorption capacity on the iron oxides increased in the order: lepidocrocite < goethite < two-line ferrihydrite. The maximum adsorption capacities of meco-prop and 2,4-D on goethite were found to be equivalent to the site density of singly coordinated hydroxyl groups on the faces of the dominant (110) form, suggesting that singly coordinated hydroxyl groups are responsible for adsorption. Differences in adsorption capacities between iron oxides can be explained by differences in the surface site density of singly coordinated hydroxyl groups. The maximum measured adsorption capacity of mecoprop on two-line ferrihydrite was equivalent to 0.2 mol/mol Fe.     

Tillage, intercrop, and controlled drainage-subirrigation influence atrazine, metribuzin, and metolachlor loss

Atrazine (6-chloro-N2-ethyl-N4-isopropyl-1,3,5-triazine-2,4-diamine) and metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide] have been found with increasing occurrence in rivers and streams. Their continued use will require changes in agricultural practices. We compared water quality from four crop-tillage treatments: (i) conventional moldboard plow (MB), (ii) MB with ryegrass (Lolium multiflorum Lam.) intercrop (IC), (iii) soil saver (SS), and (iv) SS + IC; and two drainage control treatments, drained (D) and controlled drainage-subirrigation (CDS). Atrazine (1.1 kg a.i. ha-1), metribuzin [4-amino-6-(1,1-dimethylethyl)-3-(methylthio)-1,2,4-triazine-5(4H)-one] (0.5 kg a.i. ha-1), and metolachlor (1.68 kg a.i. ha-1) were applied preemergence in a band over seeded corn (Zea mays L.) rows. Herbicide concentration and losses were monitored from 1992 to spring 1995. Annual herbicide losses ranged from < 0.3 to 2.7% of application. Crop-tillage treatment influenced herbicide loss in 1992 but not in 1993 or 1994, whereas CDS affected partitioning of losses in most years. In 1992, SS + IC reduced herbicide loss in tile drains and surface runoff by 46 to 49% compared with MB. The intercrop reduced surface runoff, which reduced herbicide transport. Controlled drainage-subirrigation increased herbicide loss in surface runoff but decreased loss through tile drainage so that total herbicide loss did not differ between drainage treatments. Desethyl atrazine [6-chloro-N-(1-methylethyl)-1,3,5-triazine-2,4-diamine] comprised 7 to 39% of the total triazine loss.     

Environmental concentrations of agricultural herbicides in Saskatchewan, Canada: bromoxynil, dicamba, diclofop, MCPA, and trifluralin

Herbicides are the most commonly used group of agricultural pesticides on the Canadian Prairies and, in 1990, more than 20000 Mg of herbicides were applied in the provinces of Alberta, Saskatchewan, and Manitoba. The present paper reports on environmental concentrations of five herbicides currently used in the prairie region. The herbicides bromoxynil [3,5-dibromo-4-hydroxy-benzonitrile], dicamba [3,6-dichloro-o-anisic acid], diclofop [(RS)-2-[4-(2,4-dichlorophenoxy)-phenoxy]propanoic acid], MCPA [(4-chloro-2-methylphenoxy)acetic acid], and trifluralin [alpha,alpha,alpha-trifluoro-2,6-dinitro-N,N-isopropyl-p-toluidine] were measured in the atmosphere, bulk atmospheric deposits, surface film, and dugout (pond) water at two sites near Regina, Saskatchewan, during 1989 and 1990. All five herbicides were detected in air and surface film and all but trifluralin were detected in the bulk atmospheric deposits and dugout water. Trifluralin was most frequently detected in air (79% of samples) whereas bromoxynil was present in maximum concentration (4.2 ng m(-3)). MCPA was present in maximum levels in bulk atmospheric (wet plus dry) deposits (2350 ng m(-2) d(-1)), surface film (390 ng m(-2)), and dugout water (330 ng L(-1)), whereas dicamba was most frequently detected in surface film (47%) and dugout water (97%). The highest quantities of the herbicides tended to be present during or immediately after the time of regional application.