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61.
以金属作为基底,环氧树脂作为涂层材料,采用电化学阻抗谱技术研究表面未经处理、经硅烷处理和经磷化处理试样的环氧涂层酎蚀性能。有机涂层试样做为工作电极,浸泡在3.5%的NaCl水溶液中,测量其交流阻抗谱。结果表明:金属表面经硅烷处理后,金属/涂层的酎蚀性优于未经表面处理和经磷化处理的试样,硅烷处理层能很好地保护金属基底。  相似文献   
62.
通过船舶三维运动程序进行了船舶运动与波浪载荷的初步分析.以一艘5500 TEU集装箱实船为例,通过设置不同航行条件来确定与运动和载荷最大值对应的航向角,得到了单位规则波作用下的运动振幅以及各种航向角下中剖面的受力转换函数和受力转换频谱,得到了主要载荷参数最大值所在位置、数值以及相应的航行条件,最后运用波谱理论进行了长期波浪载荷分析,并与现行规范进行了比较.该结论可用于集装箱船极限载荷分析,也可为船体结构设计提供参考.  相似文献   
63.
Participatory processes in scenario development have received increasing attention throughout the last years. Combining qualitative stakeholder and quantitative expert information (i.e. modelling) offers unique opportunities to mix good data, scientific rigour, imagination and expertise from different perspectives. However, this task is all but easy as it requires a careful balancing of approaches and an acceptance of different levels of knowledge and trust in different methods across disciplinary boundaries. In spite of a growing body of literature we are still in the early stages of learning how to deal effectively with participatory scenario development. In the PRELUDE project of the European Environment Agency a relatively far-reaching participatory approach to scenario development was applied: a group of stakeholders from across Europe was given full responsibility to develop long-term alternative land use scenarios in cooperation with experts and modellers. The scenarios have been used in a formal outreach process with key clients and stakeholders at the European and Member State level afterwards. The aim of this paper is to document the methods used, analyse their strengths and weaknesses and draw some general conclusions regarding participatory processes in scenario development. This paper argues that in future scenario development more attention needs to be paid to strengthen the integration of qualitative and quantitative analysis. A set of compelling and coherent storylines can effectively trigger strategic conversations among policy-makers and key stakeholders about potential future developments and related response strategies. A weak integration with quantitative results can undermine this outcome, which is one of the ultimate objectives of any scenario exercise.
Axel VolkeryEmail:
  相似文献   
64.
AZ91D镁合金植酸转化膜组成与耐蚀性能研究   总被引:18,自引:0,他引:18  
采用一种环保型金属处理剂植酸对AZ91D镁台金进行化学转化处理,并通过电化学测试技术和化学浸泡方法考查其耐蚀性能.结果表明,经植酸处理后,与传统的铬酸盐制品相比,在室温模拟汗液中,AZ91D镁合金的腐蚀电位从-1.6V提高到-1.2V(SCE);在相同电位下,阳极极化电流密度减小5个数量级,电化学性能得到显著改善.涂覆聚丙烯酸树脂后,在模拟汗液中浸泡72h没有观察到腐蚀迹泉.根据扫描电镜观察、电子能谱分析和衰减全反射红外光谱测试结果,发现植酸在镁台金表面发生化学吸附,以植酸盐的形式在合金表面形成一层致密的、具有网状裂纹的转化膜.该转化膜能够有效地阻止浸蚀性阴离子与金属基体接触,从而提高了镁合金的耐蚀性能.  相似文献   
65.
徐矿集团旗山煤矿通过在企业文化建设中的不断摸索和实践,逐步形成了旗山特色的安全文化模式.基本实现了人、物、系统、制度"四大要素"的和谐统一,初步建立了长效安全机制.  相似文献   
66.
对焦化厂循环水管道的化学清洗和防腐处理技术进行了研究,并给出了实施方案。  相似文献   
67.
Prediction of CO2 leakage into biosphere is very important for risk assessment in geological carbon storage projects. Underground CO2 can be transported into bio- sphere through short term leakage due to fractures of wellbores or cap rocks, which has been extensively investi- gated, and long term leakage due to diffusion, which has few relevant studies. This paper presents a diffusive model for CO2 gradual leakage into biosphere during a long period after CO2 injection. First, the paper describes a general dif- fusive model with long term secondary trapping effects for C02 fluxes from underground into biosphere. Secondly, a simplified one-dimensional model is presented and solved for the CO2 concentrations in groundwater. The results show that the groundwater CO2 concentration will reach the maximum value at about 50th year after CO2 injection and then slowly decrease due to secondary trapping effects. Moreover, the partition coefficient is the dominant parameter for predicting the groundwater CO2 concentration while the convective mass transfer coefficient plays an insignificant role.  相似文献   
68.
本对炼油行业的节能潜力进行分析,给出了几条节能降耗措施。同时结合自身工作经验,总结常减压蒸馏装置的节能降耗措施:努力提高加热炉效,开好变频泵,控制循环水用量,利用低温位热量优化工艺操作,凝结水回收再利用等一系列措施。实践证明这些措施准确有效。  相似文献   
69.
 采用硅烷偶联剂对氧化石墨烯进行改性后制备了表面功能化石墨烯,并以此功能化石墨烯制备了稳定分散的石墨烯浆料。将此浆料与溶解好的树脂液、预分散好的锌粉浆料混合,制备了石墨烯冷涂锌涂料。通过盐雾试验、接触角试验及电化学测试,确定了石墨烯在涂料体系中的最佳添加量。对石墨烯冷涂锌涂料的性能进行了全面测试,结果显示,涂层耐盐雾时间达到2500 h,是相同厚度热浸锌涂层的2倍以上。  相似文献   
70.
Aging treatment is an effective way to optimize the mechanical properties of Co-based superalloys. In this study, commercial GH 605 superalloy was subjected to aging treatment at 650 ?°C in a wide time range up to 1000 ?h. The effects of aging time on the tensile characteristics, microstructure evolution and mechanical properties were systematically investigated at room temperature (RT) and 900 ?°C. The results showed that the volume fractions of M6C and M23C6 carbide increased with the aging time. After long-term aging treatment, the yield strength (YS) at RT was enhanced from 490.3 ?MPa to 805.9 ?MPa, while the alloy still had high tensile ductility (above 20%). Microscopic observations by transmission electron microscopy (TEM) indicated that the strengthening mechanism was related to carbide precipitation inside the grains and the change in the dislocation slipping mode. Moreover, long-term aging treatment can increase the elongation from 24.1% to 47.3% at 900 ?°C accompanied by a slight increase of YS from 299.3 ?MPa to 313.9 ?MPa. Based on detailed microstructure analysis the strengthening mechanism can be attributed to the refined grains as well as carbide precipitation inside the grains and around the grain boundaries.  相似文献   
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