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1.
合金元素对铝合金在泰国曼谷地区初期腐蚀行为的影响   总被引:1,自引:0,他引:1  
在泰国曼谷地区对5083、6063和7020 3种铝合金进行为期1 a的暴晒实验,采用SEM、电化学实验、XPS和扫描Kelvin探针显微镜(SKPFM)对3种铝合金初期腐蚀形貌及腐蚀机理进行研究。结果表明:6063铝合金中Mg、Si、Fe等合金元素含量较少,腐蚀电位相对较高,约为-0.66 V (vs SCE),腐蚀产物膜较为致密,耐蚀性较好,在泰国曼谷地区的腐蚀速率约为0.7 g/(m^2·a)。7020铝合金含有较多Mg、Zn等合金元素,腐蚀电位约为-0.78 V (vs SCE),腐蚀最为严重,腐蚀速率约为3.26 g/(m^2·a)。3种铝合金均含有Mn、Si、Fe等合金元素,从而形成Fe-Si-Al或Fe-Si(Mn)-Al第二相,第二相表面电位高于基体225~280 mV,在大气环境中第二相作为阴极相,周围的基体Al优先溶解脱落,成为点蚀坑。  相似文献   
2.
This article covers recent developments of material research in Thailand with a focus on environmental sustainability. Data on Thailand’s consumption and economic growth are briefly discussed to present a relevant snapshot of its economy. A selection of research work is classified into three topics, namely, (a) resource utilization, (b) material engineering and manufacturing, and (c) life cycle efficiency. Material technologies have been developed and implemented to reduce the consumption of materials, energy, and other valuable resources, thus reducing the burden we place on our ecological system. At the same time, product life cycle study allows us to understand the extent of the environmental impact we impart to our planet.  相似文献   
3.
研究在电化学水处理中,电场对Ca CO3结晶形态的影响。正常情况下,Ca CO3形成稳定方解石型,其晶型通常为排列整齐、结构致密、质地坚硬的方解石型,难以去除。但在电场效应作用下,电流为0.3 A、极板间距为50 mm时,电场力能有效地促使Ca CO3结晶形式转变为较为疏松的纹石型和球霰石型晶体,使其不容易附着在管道壁上且便于剥离去除。  相似文献   
4.
通过地质勘查和综合研究工作,在青海柴北缘新发现了一个中型规模的金矿床——青山金矿。青山金矿位于柴北缘赛什腾山—阿尔茨托山造山亚带,是滩间山地区继金龙沟金矿床、细晶沟金矿床、青龙沟金矿床之后发现的又一处具有较好找矿潜力的矿床。根据野外地质工作,结合室内综合研究,讨论了青山金矿床的矿床地质特征、控矿因素。青山金矿属于中—低温热液构造破碎带型金矿床。通过青山金矿的发现,证明柴北缘地区仍具有良好的寻找构造蚀变岩型金矿的前景。  相似文献   
5.
赵燕伶  谢涛  荣豪  郝旋捷  杨张瑜  李宁 《矿产勘查》2023,14(9):1740-1748
为全面掌握秦岭北麓建设用地分布情况及转化机制,促进资源、环境协调可持续发展。本文选取秦岭北麓建设用地作为研究对象,以2019—2021年的高分一号影像数据作为数据源。通过建立样本库,选取实验区,采用FCN(fully convolutional networks 全卷积神经网络)算法对实验区和秦岭北麓全区多时序影像进行智能提取,实现秦岭北麓建设用地变化监测。从对建设用地图斑分布情况、变化趋势以及变更因素的分析来看,秦岭北麓12个季度建设用地面积整体呈现增长趋势,建设用地转入类型以其他用地和耕地为主,转出则以其他用地为主。通过有效掌握秦岭北麓建设用地变更机制,对提升国土综合监管及社会服务能力具有重要意义。  相似文献   
6.
冀北温家营-马家沟银多金属矿区矿(化)体受NWW向断裂构造所控制,与硅化、高岭土化、褐铁矿化、黄铁矿化、方铅矿化、铁锰染关系密切,显示出高极化特征。因地表覆盖厚、深部找矿依据不足,未能很好地评估矿区找矿潜力。本次采用大功率激电中梯测量辅以激电测深对矿区进行了探索,圈定了多处高极化异常体,结合测深断面异常特征,查明了矿(化)体的赋存位置,明确了找矿范围。经钻探深部验证,发现了9条隐伏铅锌矿体及多条铅锌银矿化体,与异常部位对应吻合,表明激发极化法对本区寻找银多金属矿是行之有效的,可为类似矿区开展含硫化物银多金属矿勘查提供很好的借鉴。  相似文献   
7.
While Thai overseas investment projects (TOIPs) have become a key form of development in the region, their environmental impact assessment (EIA) quality has been criticized. This research sought to analyze the differences in EIA practices in terms of public participation (PP) in two TOIPs – the Hongsa coal-fired power plant (Lao PDR) and the Dawei special economic zone (Myanmar) – versus a national-level project, the Krabi coal terminal. For Laos and Myanmar, which did not previously require PP, the Thai consultants did not apply the Thai PP framework, leading to poor public participation index (PPI) scores = 0.02, indicating a negligible PP process. However, the consultant on the Krabi coal terminal claimed to abide by the Thai regulations, yet the PPI scores claimed = 0.81 (substantive rationale), were quite different from those indicated by the affected villagers = 0.39 (instrumental rationale). These villagers’ concerns resulted in conflict between the affected villagers and project owners. Our findings have revealed the true necessity of PP regulation and systems to monitor consultant performance to ensure sustainability of TOIPs in neighboring countries.  相似文献   
8.
This research aims to investigate the underlying process-based causes of e-government failure. Through the lens of actor-network theory, this paper presents a process-oriented study of the failure of Thailand’s Smart ID Card project. Adding to the extant knowledge on e-government failures that attributes this phenomenon to internal and external factors, this paper argues that the reason the project failed was a cumulative process of failure to create and maintain the actor-network. Policy implications for developing countries to efficiently manage their e-government initiatives are given, such as adopting an open principle in setting e-government project objectives and initiating the actor-network; implementing the e-government target in stages based on prepared environment; allowing an e-government system to evolve according to the degree of readiness in the information and communications technology (ICT) system design, implementation and local adoption; and including large, nationwide projects as part of a national informatization strategy.  相似文献   
9.
Inland farming of marine shrimp species is a relatively recent development, in response to increasing demand for the products. This study aimed to investigate the prevalence and antimicrobial resistance of potentially pathogenic Vibrio species in shrimps cultured at inland ponds with low salinity in Thailand. Of 16 shrimp samples (white-leg shrimps and black-tiger shrimps) from ponds with water temperatures from 29 to 32 °C, and salinities from 1 to 5 parts per trillion, 15 contained Vibrio cholerae (densities: 62–252,000 MPN/g). Vibrio parahaemolyticus was present in six samples (370–6,300,000 MPN/g), and Vibrio vulnificus was present in two samples (16–1300 MPN/g). V. parahaemolyticus has higher affinity for non-native white-leg shrimp than for native black-tiger shrimp. The minimum inhibitory concentrations were then measured for 12 common antimicrobial agents. Resistance to ampicillin and oxytetracycline (8% and 2% of the isolates) was documented in V. cholerae isolates, resistance to ampicillin and oxytetracycline (72% and 3%) was found in V. parahaemolyticus isolates, and resistance to nalidixic acid (20%) was detected in V. vulnificus isolates. β-lactamase and tetracycline resistance genes were detected in the resistant Vibrio isolates. The oxytetracycline-resistance phenotype was eliminated by plasmid curing, suggesting that the resistance was related to R-plasmids. Our results show that shrimps cultured even in low salinity ponds are potentially contaminated with pathogenic Vibrio species, and that shrimp are a vehicle for transfer of species with antimicrobial resistance genes to the public.  相似文献   
10.
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