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Florias Mees Etienne Cornelis Patric Jacobs Maria Teresa Domnech Crbo Hannelore Rmich 《Engineering Geology》2009,103(3-4):93-99
Microfocus X-ray computed tomography (µCT) is a useful tool for non-destructive analysis of corroded archaeological glass objects and for monitoring restoration and conservation processes for these materials. This was demonstrated by µCT analysis of artificially corroded laboratory-produced glasses and corroded archaeological glasses retrieved from soil environments. Corrosion layers with a thickness of 20 µm or more can be detected as areas with lower X-ray attenuation values than the non-corroded glass. Features that are revealed by µCT analyses include the degree and patterns of corrosion and the presence of various internal structures in the corrosion layers. The study of restored corroded glasses demonstrates that mechanical and laser cleaning can be monitored efficiently. The study of consolidation practices, using test objects, requires the use of additives to increase X-ray attenuation values of the organic compounds that are used. 相似文献
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论贵东岩体东西部花岗岩岩石学特征和铀成矿条件差异性 总被引：10，自引：1，他引：10
通过对贵东岩体花岗岩岩石学特征和铀地球化学性状的系统研究,认为贵东岩体主体花岗岩是由有一定时间间隔的三期花岗岩在空间上的复合,即东部的下庄岩体、东南部的鲁溪岩体和西部的隘子岩体,三期花岗岩为不同源区地壳物质部分熔融的产物。东部下庄岩体的富铀性和铀的强烈活化,使它成为该区唯一有利的成矿铀源体,阐明了贵东岩体东部成矿西部不成矿的根本原因,指出今后的找矿重点还应放在东部地区。 相似文献
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The influence of parent rock and soil material on the corrosion rate of metallic fragments that remained in soil after World
War I in the Soča front area (Slovenia), as well as the corrosion products of these fragments, were studied. The results of
corrosion tests did not indicate appreciable differences in corrosion rates between various corrosion media. Consequently,
the corrosion rates are influenced mostly by soil aeration, soil humidity and also by microstructures of alloys. Soil type
seems to have the most influence on corrosion products. For the pH and Eh ranges that prevail in the studied soils, goethite
is the only stable iron mineral. Lead minerals are not stable, and lead, in a Pb2+ cation form, is probably adsorbed onto some minerals – especially goethite – or is bound with organic matter. In distric
brown soil, lead stays in the cation form as Pb2+ because of high soil acidity. Cuprite is stable in rendzina and brown soil on limestone, whereas in distric brown soil copper
stays in solution as Cu2+.
Received: 7 October 1999 · Accepted: 8 March 2000 相似文献
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钢在不同海底沉积物中的腐蚀研究 总被引：3，自引：1，他引：3
1993年9月—1994年9月在中国科学院海洋研究所培育楼流动海水实验室将普通碳钢（A3钢）和低合金钢（16Mn钢）以分别和电连接两种挂片方式置于海面大气区、海水全浸区和不同的海底沉积物中进行一年的室内模拟实验。结果表明，两种钢在海洋环境中的腐蚀率在分别挂片时呈下列顺序：海面大气区＞海水全浸区＞海底沉积区；在电连挂片时出现如下顺序：海面大气区＞海底沉积区＞海水全浸区。随着海底沉积物颗粒度的减小，水／泥（砂）界面腐蚀最轻的钢片的腐蚀速度在电连挂片时成正相关关系，分别挂片时影响不大。处于沉积区最底部的钢片因成为宏电池的阳极，而遭受最严重的腐蚀。低合金钢的腐蚀率比普碳钢略大。 相似文献
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The Red River drains 242000 km2 with 90% of this area being downstream of discharges from naturally occurring brine seeps and springs. The upstream area
has been designated as a major chloride emission area in Texas and Oklahoma. Ten major brine source emission areas along the
tributaries to the Red River were identified by U.S. Public Health Service and U.S. Army Corps of Engineers. Eight of these
areas were deemed suitable for the control of brine emissions by structural methods including a ring dike to enclose brine
springs; low flow dams to capture and divert stream flows with high chloride content to evaporation lakes; and shallow aquifer
brine collection wells with a deep-well disposal system. Two adjacent emission areas, designated as Areas XIII and XIV, contribute
500 metric tons of salt per day to the Red River. These areas, along Jonah Creek and Salt Creek, tributaries to the Prairie
Dog Town Fork of the Red River were selected for investigation to control brine emission by utilization of shallow collection
wells and disposal by deep injection wells. Drilling programs and pumping tests were performed to determine the number and
location of shallow collection wells. Eighteen wells with 12 operating full time, will be located in the primary emission
areas. The collected brine will be conveyed through corrosion-resistant pipelines to a treatment facility for filtration at
a rate of 300 l/s. Additional pipelines will convey the filtered brine to deep injection wells for disposal. Nine deep wells
will be installed with seven operating full time. Design criteria for the project are 100-year life expectancy and automated
operation with minimum supervision and maintenance. The required minimum operating, maintenance and supervision coupled with
100-year life expectancy of the project added significantly to the estimated US $58 million capital cost of the project. However,
the reduction in annual cost for labor, repairs and replacement of the component of the system should result in a lower life
cycle cost. The estimated annual operating and maintenance cost is US $4.7 million.
Received: 5 May 1998 · Accepted: 30 June 1998 相似文献
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Artificial neural networks and their application to assessment of ultimate strength of plates with pitting corrosion 总被引：1，自引：0，他引：1
The potential for the structural capability degrading effects of both corrosion and fatigue induced cracks are of profound importance and must be both fully understood and reflected in vessel's inspection and maintenance programme. Corrosion has been studied and quantified by many researchers, however its effect on structural integrity is still subject to uncertainty, particularly with regards to localized corrosion. The present study is focused on assessing the effects of localized pitting corrosion on the ultimate strength of unstiffened plates. Over 265 non-linear finite-element analyses of panels with various locations and sizes of pitting corrosion have been carried out. The results indicate that the length, breadth and depth of pit corrosion have weakening effects on the ultimate strength of the plates while plate slenderness has only marginal effect on strength reduction. Transverse location of pit corrosion is also an important factor determining the amount of strength reduction. When corrosion spreads transversely on both edges, it has the most deteriorating effect on strength. In addition, artificial neural network (ANN) method is applied to derive a formula to predict ultimate strength reduction of locally corroded plates. It is found out that the proposed formulae can accurately predict the ultimate strength of locally corroded plates under uniaxial in-plane compression. 相似文献