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Cr_2O_3对高放核废料磷酸盐玻璃固化体的影响

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无机材料学报 2005年第4期20卷 842-850页

作者：黄文旵周萘 Day Delbert e Ray Chandra S 同济大学材料学院 University of Missouri-Rolla Rolla MO 65409USA

在含高放核废料的玻璃固化体中添加了不同含量的Cr2O3,以考察其对玻璃固化体的结构和性质的影响.对添加Cr2O3的玻璃固化体进行了各种方法(溶出速率法,蒸汽水化侵蚀和试样坚固性法)的化学稳定性的测试.测试结果表明,Cr2O3的引入不会对玻... 详细信息

在含高放核废料的玻璃固化体中添加了不同含量的Cr2O3,以考察其对玻璃固化体的结构和性质的影响.对添加Cr2O3的玻璃固化体进行了各种方法(溶出速率法,蒸汽水化侵蚀和试样坚固性法)的化学稳定性的测试.测试结果表明,Cr2O3的引入不会对玻璃固化体的化学稳定性产生不良的影响.与此相反,Cr2O3能抑制各种离子自玻璃固化体中沥析出来, 改善玻璃固化体的化学耐蚀性. XRD内标法测定,Cr2O3在铁磷酸盐玻璃中的溶解度可达4.1%,是其在硼硅酸盐玻璃的3倍. FTIR和DTA的结果表明,不同含量的Cr2O3的引入, 不会对玻璃固化体的网络结构造成显著的变化. Mossbauer谱表明,fe2+/fe3+的比值随着Cr2O3的含量的增加而增大,说明Cr离子和fe离子在玻璃熔制过程中发生氧化还原反应, 形成的Cr+6有利于提高玻璃固化体的化学耐蚀性.

关键词：铁磷玻璃氧化铬核废料处理化学稳定性

Batch and fixed-bed column studies of selenite removal from contaminated water by orange peel-based sorbent

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Water Science and engineering 2020年第4期13卷 307-316页

作者： Barbara Perez Mora fernando A.Bertoni María F.Mangiameli Juan C.Gonzalez Sebastian e.Bellu Faculty of Biochemical and Pharmaceutical Sciences National University of RosarioRosario S2002LRKArgentina Chemistry Institute of Rosario National Council of Scientific and Technological ResearchRosario S2002LRKArgentina

Orange peel is a biomass derived from citrus processing with desirable properties for metal *** recent years,orange peel has been used to remove various heavy metals and toxic ***(Se)is an essential trace element for ***,when the concentration of selenium exceeds an umbral limit,it becomes *** this study,orange peel was used to treat Se(IV)-contaminated water.A high sorption capacity of 32.5 mg/g was obtained at a temperature of 20℃and a pH of *** groups bound Se(IV)to the surface of the orange *** sorption process was spontaneous and endothermic.A chemical sorption mechanism was involved in the removal of Se(IV).The Thomas and modified dose-response models were used to simulate the experimental breakthrough *** bed depth service time model was used to calculate the critical bed depth(Z0),and the calculated Z0 value was 1.6 *** study reveals that orange peel is a useful sorbent for Se(IV),and can be used for the purification of Se(IV)-contaminated water.©2020 Hohai *** and hosting by elsevier *** is an open access article under the CC BY-NC-ND license(http://***/licenses/by-nc-nd/4.0/).

关键词： Sorption Orange peel Removal of heavy metal Selenium-contaminated water Sorbent Breakthrough curve

Temperature and composition dependent screw dislocation mobility in austenitic stainless steels from large-scale molecular dynamics

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npj Computational Materials 2020年第1期6卷 176-185页

作者： kevin Chu mich.e. e.Foster Ryan B.Sills Xiaowang Zhou Ting Zhu David L.McDowell school of Materials Science and engineering Georgia Institute of Technology AtlantaAtlantaGA 30332USA Sandia National Laboratories LivermoreCA 94550USA Department of Materials Science and engineering Rutgers UniversityPiscatawayNJ 08854USA Woodruff school of Mechanical engineering Georgia Institute of TechnologyAtlantaGA 30332USA

extensive molecular dynamics simulations are performed to determine screw dislocation mobility in austenitic fe_(0.7)NixCr_(0.3-x) stainless steels as a function of temperature ranging from 100 to 1300 k,resolved shear stress from 30 to 140 MPa,and Ni composition from 0.0 to 30.0 at%.These mobility data are fitted to a linear mobility law with a nonzero stress offset,referred to as the threshold *** find that both the linear drag coefficient and the threshold stress increase with Ni *** drag coefficient increases with temperature,whereas the threshold stress decreases with *** on these calculations,we determine fitting functions for the linear solute drag coefficient as a function of temperature and *** mobility laws determined in this study may serve to inform dislocation dynamics simulations pertinent to dislocation network evolution at elevated temperatures for a wide composition range of austenitic stainless steels.

关键词： austenitic dislocation dynamics

Structure-from-Motion Photogrammetry and Rare earth Oxides can quantify diffuse and convergent soil loss and source apportionment

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International Soil and Water Conservation Research 2023年第4期11卷 633-648页

作者： Pia Benaud karen Anderson Mike R.James Timothy A.Quine John N.Quinton Richard e.Brazier CReWW GeographyFaculty of EnvironmentScience and EconomyUniversity of ExeterExeterDevonEX44RJUnited Kingdom environment and Sustainability Institute University of ExeterPenrynCornwallTR109FEUnited Kingdom Lancaster environment Centre Lancaster UniversityBailriggLancasterLA14YQUnited Kingdom Geography Faculty of EnvironmentScience and Economy.University of ExeterExeterDevonEX44RJUnited Kingdom

Accurately quantifying rates of soil erosion requires capturing both the volumetric nature of the visible,convergent fluvial pathways(also known as rills)and the subtle nature of the less-visible,diffuse pathways(interrill areas).The aim of this study was to use Rare earth Oxide(ReO)tracers and Structure-from-Motion(SfM)photogrammetry to elucidate retrospective information about soil erosion rates and sediment sources during different soil erosion conditions,within a controlled laboratory *** experimental conditions created erosion events consistent with diffuse and convergent erosion *** tracers allowed the sediment transport distances of over 2 m to be described,and helped resolved the relative contribution of diffuse and convergent soil erosion;interrill areas were also iden-tified as a significant sediment sources soil loss under convergent erosion *** the potential for SfM photogrammetry to resolve sub-millimetre elevations changes was demonstrated,under some conditions non-erosional changes in surface elevation,such as compaction,exceeded volumes of soil loss via diffuse *** discrepancies between SfM Photogrammetry calculations and ReO tagged sediment export were beneficial,identifying that during soil erosion events sediment in both aggregate and particle form is deposited within the convergent features,even when the rill extended the full length of the soil *** combination of SfM photogrammetry and ReO tracers has provided a novel platform for building a spatial understanding of patterns of soil loss and source apportionment between rill and interrill erosion.

关键词： Soil erosion Structure-from-Motion Photogrammetry Rare earth Oxides Tracers Sediment Rainfall simulator Sheetwash Rilling Interrill

Photodegradation of Bisphenol A Induced by Metal Ions in Aqueous Solution in the Presence of Ascorbic Acid

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Wuhan University Journal of Natural Sciences 2008年第1期13卷 107-112页

作者： PeNG Zhang＇e ZHANG Xu YANG Liu WU feng DeNG Nansheng school of Resources and environmental Sciences Wuhan University Wuhan 430079 Hubei China

The photodegradation of bisphenol A （BPA） in aqueous solution containing metal ions and ascorbic acid （AsA） was investigated. After strong irradiation, the aqueous solution containing AsA and Cu^2＋ could produce hydroxyl radicals that induced the photodegradation of BPA. The photodegradation efficiency of BPA in the solution containing 70 μmol·L^1 Cu^2＋ and 15 mg·L^1 AsA reached 59% at pH 6.0 after 4 hours irradiation with high pressure mercury lamp. The photodegradation efficiency of BPA reached 10% after 4 hours irradiation with daylight lamp in the presence of 70 μmol·L^1 Cu^2＋ and 15 mg·L^1 ascorbic acid. BPA was not degraded in the aqueous solution only containing AsA or Cu^2＋. The BPA photodegradation in aqueous solution containing AsA and fe^3＋ was weaker than in aqueous solution that containing AsA and Cu^2＋ at the same concentration. This work showed a new route of the BPA photodegradation in aqueous environment.

关键词： bisphenol A photodegradation metal ions hydroxyl radicals

Model-Based Identification of Mechanical Characteristics of Sinosaurus(Theropoda) Crests

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Acta Geologica Sinica(english edition) 2015年第1期89卷 1-11页

作者： XING Lida WANG Yikun eric SNIVeLY ZHANG Jianping DONG Zhiming mich.e. e.BURNS Philip J.CURRIe school of the earth Sciences and Resources China University of Geosciences Auckland Bioengineering Institute The University of Auckland Department of Mechanical engineering Ohio University Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Department of Biological Sciences University of Alberta Alberta T6G 2e9 Canada

The paired cranial crests of Sinosaurus （Theropoda） have been hypothesized as too weak to resist mechanical loads during combat. Finite element analysis （feA） is used to test this hypothesis, first with geometry obtained through direct laser scanning of a well-preserved fossil of the crest, and then with two conceptual fe models of both crests analyzing the structure-deformation effects of fenestration. In the original fossil model, under direct loading on the dorsal faces of the crest, we found that the areas surrounding cavities on the crest experience shear stress that implies a high chance of material failure - the fracture of bone. In the conceptual model, a series of computational studies were conducted with varying loading directions. One simulation found that the shear stress and strain in the material around the cavity presented more deformation compared with the conceptual model without the cavities, and under this morphologically realistic scenario the loading conditions would result in local bone fractures. These model-based computational results indicate that the crest could not resist high loads, because it could not effectively decentralize the loading stress. Future investigations need to focus on more comprehensive computational experiments with more conditions, e.g. dynamical loading conditions, and direct palaeontological evidence.

关键词： Dinosauria Sinosaurus behavior finite element analysis

emission of high-energy alpha particles in nuclear reactions of ^(48)Ca and ^(56)fe ions on ^(181)Ta and ^(238)U targets

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Chinese Physics C 2022年第11期46卷 177-194页

作者： Yu.e.Penionzhkevich V.V.Samarin S.M.Lukyanov V.A.Maslov M.A.Naumenko Flerov Laboratory of Nuclear Reactions Joint Institute for Nuclear ResearchDubna 141980Russia Department of experimental Methods in Nuclear Physics National Research Nuclear UniversityMoscow 115409Russia Department of Nuclear Physics Dubna State UniversityDubna 141982Russia

The results of experiments on measuring the energy spectra of alpha particles in reactions with heavy ions are *** measurements were performed using the high-resolution magnetic analyzer MAVR with beams of ^(48)Ca(280 MeV)and ^(56)fe(320 and 400 MeV)on ^(181)Ta and ^(238)U targets at an angle of 0°.A strong dependence of the double differential cross sections for production of alpha particles on the atomic number of the target nucleus was observed,which indicates that fast alpha particles are mainly emitted from the target nucleus;this conclusion was also confirmed by calculations within the time-dependent schrödinger equation *** analysis of the obtained experimental data was carried out within the model of moving sources modified to consider the kinematic limits for two-body and three-body exit channels.

关键词： alpha particle energy spectra two-and three-body kinematic limits model of moving sources time-dependent schrodinger equation

Cow manure and cow manure-derived biochar application as a soil amendment for reducing cadmium availability and accumulation by Brassica chinensis L. in acidic red soil

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Journal of Integrative Agriculture 2017年第3期16卷 725-734页

作者： Yasmin khan kiran Ali Barkat CUI Xiao-qiang feNG Ying PAN feng-shan TANG Lin YANG Xiao-e key Laboratory of environmental Remediation and ecological Health/Ministry of education College of Environmental and Resource SciencesZhejiang University State key Laboratory of Food Science and Technology School of Food Science and TechnologyJiangnan University National Agricultural Research Centre Islamabad

Organic amendment is a promising,in situ phytostabilization approach to alleviate the phytotoxic effects of heavy metal contaminated *** aim of this study was to evaluate the feasibility of cow manure（CM）and its derived biochar（CMB）as a soil amendment on cadmium（Cd）availability and accumulation in low and high Cd-accumulating cultivars of Brassica chinensis *** in an acidic red *** and CMB were applied to Cd-contaminated acidic red soil at the rates of 0,3.0and 6.0%（w/w）.Application of CMB was significantly more effective than that of CM,as it reduced the availability of Cd in soil by 34.3–69.9%and its bioaccumulation in the low Cd accumulator,Aijiaoheiye 333,by 51.2 and 67.4%,*** addition of CMB significantly increased the extractability and accumulation of trace metals（Zn,Mn,fe,and Cu）by plants and improved plant biomass *** application,combined with utilizing low Cd accumulating cultivars represents a new,sustainable strategy to alleviate the toxic effects on Cd and improve food safety.

关键词： Brassica chinensis biochar cow manure red soil phytostabilization trace metals

电极材料在铁磷酸盐玻璃熔体内腐蚀现象的研究

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稀有金属材料与工程 2006年第9期35卷 1424-1427页

作者：朱冬梅 Cheol-Woon kim Delbert e.Day 西北工业大学凝固技术国家重点实验室 Ceramic engineering Department and Graduate Center for Materials Research University of Missouri-RollaRolla MO 65401USA

选用合金Inconel690和693作为研究对象,着重研究了它们在铁磷酸盐玻璃熔体中的腐蚀行为。分别计算了不同电极材料的尺寸损失和质量损失,以及相应的损失速率,采用SeM,eDS和XRD等手段对材料表面的腐蚀层进行了分析,确定了腐蚀层的成分,主... 详细信息

选用合金Inconel690和693作为研究对象,着重研究了它们在铁磷酸盐玻璃熔体中的腐蚀行为。分别计算了不同电极材料的尺寸损失和质量损失,以及相应的损失速率,采用SeM,eDS和XRD等手段对材料表面的腐蚀层进行了分析,确定了腐蚀层的成分,主要相组成及其晶粒形态,讨论了材料腐蚀发生的可能机理。结果表明,在玻璃熔体内,合金Inconel693比Inconel690更耐腐蚀。随着腐蚀时间的延长,合金的腐蚀速率都逐渐降低。合金试样表面的腐蚀层主要由固熔体(fe,Cr)2O3组成。

关键词： Inconel合金腐蚀固熔体