磨料水射流除鳞技术在钢厂的应用

为了暴露各种钢材在热轧过程中产生的表面缺陷，需清除附于其上的氧化铁皮，称之为“除鳞”。传统的除鳞方法有酸洗、表面剥皮、喷丸处理等，这些方法存在很多缺点。本文介绍已在湖南涟钢用于生产的磨料水射流除鳞生产线，用磨料水射流除鳞具有速度快、质量高、成本低、操作简便等独特的优点。     

材料失效致因论研究

材料失效会引发产品失效,材料失效致因论主要有材料失效的累积损伤致因论、性能退化致因论、复杂环境致因论和原始缺陷致因论.研究材料失效致因论可以更加有效地预防材料及产品的失效.     

五莲县石材废料的资源化利用

石材工业是资源加工型产业,加工过程会产生大量的石材废料.我国对石材加工废料的研究起步较晚,应用技术不成熟.介绍了目前国内外对石材废料的几种主要资源化利用方式,并结合五莲县石材产业基地石材加工实际工艺及废料资源化处理方式,研究石材废料的资源化利用.     

自燃煤矸石山覆盖材料压缩及压实特性实验

自燃煤矸石山表面构建覆盖层,需要具备一定的低渗透性能以有效阻隔空气,防止煤矸石山内部发生自燃。本研究通过室内实验,测定煤矸石山构建覆盖层涉及的碾压材料包括黄土、粉煤灰及掺有粉煤灰的混合土样的界限含水率、一维压缩特性及压实特性,揭示和分析7种覆盖材料配方的压缩压实特性,表明覆盖材料通过碾压可有效阻隔空气,起到阻燃作用;将粉煤灰掺人到一般黄土材料中,可减缓混合土样击实曲线的陡峭性,从而降低材料在碾压中对含水率的敏感度。实验旨在为进行煤矸石山覆盖层碾压提供科学的实验数据及设计参数。     

微絮凝深床层过滤去除无机营养物及典型金属离子

在分析了微絮凝深床层过滤机理的基础上,实验研究了以煤矸石燃后残渣为滤料的深床层对微污染矿井水中无机营养物及典型金属离子的去除效果。结果表明,对于微污染矿井水中的NH3-N及COD的去除率仅有20%～40%;对可形成微絮凝体的磷的去除率高达80%以上,对于矿井水中的铁、锰离子的去除率可达75%以上,而絮凝剂的适量加入,不会大幅增加出水中铝离子的含量;分析表明,煤矸石燃后残渣滤料具有良好的吸附、截留作用;对溶解性NH3-N及COD的去除以吸附及生物作用,对铁、锰离子的去除则是以形成絮体沉淀为主,同时金属离子的水合作用、溶度积等对其去除有一定的影响。     

Enhancement of phosphorus sorption onto light expanded clay aggregates by means of aluminum and iron oxide coatings

Phosphorus (P) loading from non-point or point sources increases the eutrophication risk of natural waters. The functioning of constructed wetlands (CWs) used as natural water treatment systems can be improved by means of additional materials adsorbing soluble P. In this study, light expanded clay aggregates (LECA) and LECA coated with aluminum (Al) oxide (Al-LECA) or iron (Fe) oxide (Fe-LECA) were tested for their efficiency as P sorbents in the pH range 3–8. The oxide coatings duplicated the actual sorption capacity calculated from the sorption isotherms at the P concentration in the equilibrium solution of 20 μg L⁻¹, assumed to be the allowable P level in purified water. In the oxide-coated LECAs the sorption was fast and followed both the first- and second-order Lagergren kinetic models, suggesting that the formation of a binuclear surface complex was feasible. In LECA, sorption was markedly slower and followed the first-order kinetic model, indicating that retention occurred through a monodentate attachment. These findings were in harmony with the degree of P saturation (DPS) of the sorbent surfaces at the highest P addition level (200 μg L⁻¹), DPS being decisively higher for LECA than for the oxide-coated sorbents. Accordingly, at higher pH values the competition by hydroxyl ions diminished the sorption in LECA relatively more than that in the coated sorbents. In agreement with the acidity of Al³⁺ being 100 times lower than that of Fe³⁺, at elevated pH the sorption by Al-LECA proved to be less reversible than that by Fe-LECA. The results provide evidence that in CWs Al-coated sorbents are superior to Fe-coated ones that are also redox-sensitive and may lose their sorption properties in anoxic conditions.     

A GIS-based evaluation of the effect of decontamination on effective doses due to long-term external exposures in Fukushima

Despite the enormous cost of radiation decontamination, there has been almost no quantitative discussion on how much it would reduce the long-term external radiation exposure in the Evacuation Zone and Planned Evacuation Zone (restricted zone) in Fukushima. The aim of this study is to assess the effectiveness of decontamination and return options and to identify important parameters for estimating the long-term cumulated effective dose (CED) during 15, 30 and 70 year period using data on land-use, population and decontamination in the restricted zone (about 1100 km²) in Fukushima.     

海洋沉积物基质多环芳烃标准参考物质的原料样品制备研究

海洋沉积物基质多环芳烃(PAHs)标准参考物质是海洋环境沉积物监测分析中质量控制和质量保证的重要保障。由于缺少对相关原料样筛选研究,目前我国尚未有自主制备的海洋沉积物基质PAHs标准参考物质。通过海洋沉积物原始数据调研、定点筛查、实验室间验证等手段,对江苏近岸海域海洋沉积物原料样进行筛选研究。结果表明,连云港赣榆某入海口点位的海洋沉积物样品∑PAHs的质量分数为413μg/kg,该样品各粒径中的PAHs质量分数分布均匀,精密度能够满足我国海洋沉积物环境监测质量控制需求,可以为进一步制备海洋沉积物PAHs标准参考物质提供技术支持。     

57种臭氧前体有机物混合标准气体量值比对研究

标准物质的量值准确性是监测数据准确的重要前提。为科学评价57种臭氧前体有机物混合标准气体量值的准确性,研究建立了定量环进样-中心切割-气相色谱-双火焰离子化检测器分析方法与量值比对方法(E_n值法),并对市售6个品牌各2个批次标准气体开展量值比对研究。研究结果表明,4个品牌标气量值一致性、准确性较好,2个品牌存在5～22种组分量值偏离(E_n绝对值为1.0～5.3),用于开展臭氧前体有机物监测的标准物质质量仍需持续监督、提升。     

臭氧前驱体物监测用氮气中多组分VOCs气体标准物质的研制

介绍了瓶装1μmol/mol臭氧前驱体物监测用氮气中57组分挥发性有机物(VOCs)气体标准物质的研制过程,该气体标准物质严格按照《气体分析 校准用混合气体的制备 第1部分:称量法制备一级混合气体》(GB/T 5274.1-2018)所规定的配制气体标准物质的方法采用称量法制备。建立了GC-MS联用结合选择离子扫描(SIM)的分析方法,研究了目标化合物在气瓶中的均匀性和稳定性。57种目标化合物完全满足美国环保署光化学评估监测站(PAMS)关于臭氧前驱体物VOCs在线监测的技术要求。将气体标准物质分别送至中国环境监测总站和英国国家物理实验室(NPL)进行比对分析,结果良好,表明研制的气体标准物质具有较好的压力均匀性和稳定性,符合使用要求。相对扩展不确定度为5%(k=2),使用有效期为1年,取得国家二级标准物质证书,证书编号为GBW(E)083966。