二阶谱理论及在海浪研究中的应用

Ⅰ.二阶谱的性质   总被引：3，自引：0，他引：3       下载免费PDF全文

余宙文  丁平兴  孙孚 《海洋与湖沼》1993,24(5):553-559

针对目前国内对于二谱的研究及应用尚不普遍的状况，在参考国外文献以及我们已完成的有关研究基础上，系统地阐述了实过程的二阶谱，交叉二阶谱与矢量过程的旋转二阶谱，旋转交叉二阶谱的定义与概念，重点讨论了实过程二阶谱的有关性质。  相似文献   

Elevated curing temperature-associated strength and mechanisms of reactive MgO-activated industrial by-products solidified soils     

Dongxing Wang  Xiangyun Gao  Ruihong Wang  Stefan Larsson  Mahfoud Benzerzour 《Marine Georesources & Geotechnology》2020,38(6):659-671

Abstract

Alkali-activated industrial by-products (granulated blast furnace slag, Class F fly ash) by traditional alkali activator (such as NaOH and Na₂SiO₃) serves as a partial replacement for Portland cement in soil stabilization projects and suffers from environmental and technical problems. Reactive MgO – a greener and more practical alternative has recently emerged as a potential activator for slag and fly ash, but its micromechanisms of alkaline activation still need to be deeply investigated for strength improvement of soils. Hence, this study focuses on the strength and hydration properties of reactive MgO-slag and MgO-fly ash solidified soils, especially incorporating the impact of elevated curing temperature. Reactive MgO is proved to be excellent as a novel activator for activation of slag and fly ash, and their activating efficiency increases with elevated curing temperature that helps to remarkably enhance the compressive strength of soils. The major hydration products for reactive MgO-slag solidified soils, detected jointly by X-ray diffraction, scanning electron microscopy and thermogravimetric/differential thermogravimetric tests, are calcium silicate hydrate gels and hydrotalcite-like phases. The primary hydration products for MgO-fly ash solidified soils are magnesium silicate hydrate gels and Mg(OH)₂. That is just the intrinsic reason why the microstructure of solidified soils becomes much denser and the mechanical behavior is significantly improved. The minor carbonate phases such as magnesium carbonate and/or calcite are also observed in reactive MgO-slag and MgO-fly ash solidified soils, depending on the period of exposure to air. The curing temperature and binder amount are proved to be the two major factors governing the hydration process of reactive MgO-slag and MgO-fly ash blends. A higher curing temperature and binder amount can generate more hydration products, but their chemical compositions such as accurate element ratios need to be investigated in the future study.  相似文献   

Z-2000偏振塞曼石墨炉原子吸收分光光度计测定地球化学样品中痕量金   总被引：5，自引：2，他引：3  

李勇 《岩矿测试》2008,27(4):305-309

用φ=50%的王水分解样品,聚氨酯泡沫塑料吸附富集金,10g/L硫脲为解脱剂,偏振塞曼石墨炉原子吸收分光光度计测定痕量金。对干燥、灰化、原子化、净化温度和时间,以及载气流量和灯电流强度进行了讨论;对影响金吸附效果的泡塑载体和王水浓度等因素进行了研究。通过实验得到了Z-2000偏振塞曼原子吸收分光光度计最佳石墨炉分析测试条件。方法检出限为0.3ng/g,回收率为95.0%~101.0%,精密度(RSD,n=12)低于8.0%,经国家一级标准物质(GBW07243~GBW07245)分析验证,结果与标准值相符。  相似文献   

石墨炉原子吸收光谱法测定岩石和土壤中痕量镉   总被引：8，自引：6，他引：2  

邵文军  张激光  刘晶晶 《岩矿测试》2008,27(4):310-312

试样用王水、高氯酸分解。在高氯酸介质中,不经分离富集,无需添加任何基体改进剂,用石墨炉原子吸收光谱法直接测定岩石和土壤样品中的痕量镉。对试样分解、灰化和原子化温度进行了选择,优化了仪器工作条件。方法检出限为0.0066μg/g,精密度(RSD,n=12)低于8.0%。方法简单、快速、准确,适用于大批量岩石和土壤样品中痕量镉的分析。  相似文献   

溶剂萃取—石墨炉原子吸收法测定地质样品中痕量碲   总被引：2，自引：0，他引：2  

张佩瑜  金义 《岩矿测试》1990,9(2):128-131

本文研究了塞曼石墨炉原子吸收光谱法测定痕量Te的各种条件;采用甲基异丁基酮于4.8mol/L HCI中萃取Te(Ⅳ)的氯化物;以Rh为基体改进剂石墨炉原子吸收法测定有机相中Te。Te的特征质量为7.6×10~(-11)g(0.0044 A),相对标准偏差为6.51％(2ng Te,n=10)。方法用于地质试样中痕量碲的测定,灵敏、快速、准确。  相似文献   

固体悬浮液进样-石墨炉原子吸收法测定岩石矿物中痕量银     

陈友祎 《岩矿测试》1991,(4):291-294

本文初步探讨了采用超声波使固体样与溶剂形成均匀的固体悬浮液,直接进样石墨炉原子吸收光谱法测定岩石矿物中痕量Ag。对18个国家级标准样品中Ag进行了测试,结果吻合。对含Ag3.2μg/g的GSD-11 标样测定10次,其相对标准偏差为3.06％,方法特征量为1.9pg/0.0044A,测定下限可达0.1ng/ml。  相似文献   

Remediation of electric arc furnace dust leachate by the use of cementitious materials： A column-leaching test     

Josee Duchesne Guylaine Laforest 《中国地球化学学报》2006,25(B08):99-99

Disposal of industrial solid wastes in a hydrologic environment can cause environmental risks due to the mobility of toxic trace elements. It is increasingly important to find simple and inexpensive treatments to remove undesirable elements from industrial solid wastes. One of the most important problems in the secondary steel mill industry is the disposition of dusts produced from electric arc furnace. A large quantity （10-20 kg） of electric arc furnace dust （EAFD） is generated per ton of steel produced. The Toxicity Characteristic Leaching Procedure （TCLP） shows that the total Cr and Cr （Ⅵ） concentrations （9.7 and 6.1 mg/L respectively） from the EAFD studied exceeded the Toxicity Characteristic Regulatory Level. Some heavy metals of EAFD like chromium are toxics and have high solubility. Chromium （Ⅵ） is particularly problematic because it must initially be reduced before fixed in an insoluble phase. To counter this problem, the use of ordinary Portland cement （OPC） and ground granulated blast furnace slag （GGBFS） was investigated. Column leaching test was performed to evaluate the leaching of EAFD amended with GGBFS and OPC under dynamic conditions simulating heap leaching. The goal of this study is to find a simple and economic way to decrease contaminants in the leachate. Test columns have been set up to evaluate the effect of alkaline additives （OPC and GGBFS） on the geochemistry of drainage water. The control column consists of EADF only. A set of columns presents the effect of the addition of 5% by mass of OPC or GGBFS mixed homogeneously with the EAFD. Another set of columns was set up with the same quantities of OPC and GGBFS but concentrated at the base of the EAFD simulating a liner. Columns were fed three times weakly during 1 month. The parameters monitored after each flush of water include leachate volume, pH, electrical conductance and water quality （Cr-Ni-Pb-Zn concentrations）. The leaching of the control （EAFD only） presents high Cr concentration.  相似文献   

泡沫塑料富集-石墨炉原子吸收光谱法测定地质样品中微量铊   总被引：2，自引：0，他引：2  

林光西周泳德  周康明 《岩矿测试》2006,25(4):377-380

采用HF-HClO4-HNO3-HCl溶解样品，泡沫塑料富集-石墨炉原子吸收光谱法测定岩石、土壤、水系沉积物等地质样品中微量铊。以抗坏血酸为基体改进剂，Fe^3＋加入量选择100mg，灰化温度为600℃，原子化温度为1600℃。方法用于测定国家一级标准物质，结果与标准值基本一致。方法精密度（RSD，n=8）为2．88％～6．27％，回收率为95．24％～101．3％，检出限可达0．058μg/g。  相似文献   

The Use of Waste Materials in the Passive Remediation of Mine Water Polution     

Lesley C. Batty  Paul L. Younger 《Surveys in Geophysics》2004,25(1):55-67

The contamination and resulting degradation of water coursesby effluents from abandoned and active mines is a world-wideproblem. Traditional methods of remediating the dischargesfrom mines involve the addition of chemicals and the utilisationof artificial energy sources. Over the last 15–20 years passivetreatment systems have been developed that harness naturalchemical and biological processes to ameliorate the potentiallytoxic effects of such discharges. There are many different typesof passive system, including compost wetlands, reducing andalkalinity producing systems (RAPS), permeable reactive barriersand inorganic media passive systems. Different waste materialscan be utilised as reactive media within each of these systems,dependent upon the type of mine water and treatment technology.In many cases the reactivity of these recycled waste materialsis key to the remedial performance of these systems. The materialsused may be organic (e.g., composts) or inorganic (e.g., blast furnaceslag) and where possible are sourced locally in order to minimisetransport costs. The remediation of mine waters in itself canproduce large quantities of waste products in the form of ironoxide sludge. Potential uses of this material in the productionof pigments and in the treatment of phosphate contaminatedwaters is also currently under investigation.The exploitation of what are traditionallythought of as waste materials within treatmentsystems for polluted waters is an expandingtechnology which provides great scope for recycling.  相似文献   

石墨炉蒸发硫化铝双原子分子吸收光谱法测定硫     

周小力 《岩矿测试》1994,13(2):118-120

介绍了以空心阴极灯代替连续光源，确定了硫化铝双原子分子吸收光谱法测硫的最佳条件，方法的灵敏度（０．００４４Ａ）为３×１０￣（－９）ｇＳ，测定含Ｓ１０ｇ／ｍｌ试样１０次，其ＲＳＤ为３．３％，标准加入回收率在９９％～１０４％之间。用所拟方法测定了大气硫酸盐化速率，结果与比色法符合。  相似文献