Too Big To Fail

Sarah Dunn and Martin Felsen of UrbanLab tackle the timidity of current practice: ‘Why, as a discipline, do we think that we can counter big crises with small ideas?’ They call for a contemporary revival and redefinition of the megastructure. This is exemplified by their project for the Free Water District (FWD) in the Great Lakes, which enables the infrastructural reconstruction and urban renewal of a post-industrial landscape.     

一个大豆锈病新抗源的筛选与鉴定

采用离体叶片接种方法对2007-2010年收集的1 000份大豆种质资源进行抗性筛选,得到1份高抗材料SX6907。SX6907在接种锈菌后20d不产生侵染病斑;在接种高浓度锈菌时,产生少数红褐色RB（Red-brown）病斑,但无孢子堆破裂现象,无孢子产生;已知抗病品种（除日向外）在本研究抗性鉴定中主要表现为黄褐色TAN型感病病斑,抗性丧失。组织学观察表明,SX6907在接种部位造成细胞坏死,侵染点无孢子形成,其抗性表现为抗锈菌扩展。SX6907是一个优异的抗锈病资源,可做亲本在抗锈病育种中应用。     

蒸汽回转干燥机“T”换热管的改造及应用

通过技术分析、焊接试验、结构改造,优化换热管的加工及结构,并成功应用于生产实践中。     

Long-term monitoring of atmospheric corrosion at weathering steel bridges by an electrochemical impedance method

Weathering steel corrosion was monitored for one to two years under natural atmosphere by an electrochemical impedance technique. Two identical comb-shape weathering steel sheets embedded in epoxy resin were used as monitoring probe electrodes at two different bridges in Japan. Impedances at 10 kHz (Z_10kHz) and 10 mHz (Z_10mHz) were automatically measured every hour. Coupons (50 × 50 × 2 mm³) prepared from the same steel sheets were exposed together to measure the corrosion mass loss. The average (Z_10mHz)⁻¹ value for half to one year exposure correlated well with the average corrosion rate determined from the corrosion mass loss.     

一种通用型微乳化金属切削液的研制

通过正交实验和配方优化研制出具有自主品牌的,适用于金属材料：不锈钢、铜、铝及铝合金、钛合金等材料的切削、磨削、钻孔及数控加工的微乳化切削液,性能达到或超过国内外同类产品,对机床、工件无锈蚀,对人体和生态无害,具有较好的防锈性和极压性。     

Mechanisms of long-term anaerobic corrosion of iron archaeological artefacts in seawater

An iron ingot immersed during 2000 years at 12 m depth in the sea has been examined with the help of a combination of microscale techniques. This methodology allowed us to show that the main phase precipitated during the immersion is an iron hydroxychloride (β-Fe₂(OH)₃Cl) that is characteristic of corrosion in anoxic and chlorinated medium. Moreover locally on the external part of the corrosion products sulphur containing phases have been identified as mackinawite (FeS) in nanocrystalline or slightly oxidised state. The presence of this phase could be explained by the activity of sulphate-reducing bacteria. The presence of β-Fe₂(OH)₃Cl could be interpreted via a thermodynamic modelling taking into account the environmental conditions.     

碳酸环己胺用于化工装备气相保护的研究

研究了气相缓蚀剂碳酸环己胺（CHC）用于化工装备保护的可能性。结果发现,CHC只要有饱和蒸气存在就可以提供良好的保护,而一旦脱离其蒸气氛围,即失去对金属的保护作用,并认为CHC属物理吸附型缓蚀剂。试验结果证明,CHC只能用于密闭体系,得出与目前普遍认为CHC可用于经常打开的包装体系相反的结论。     

自燃煤矸石集料含硫量抑制研究

用自燃煤矸石集料制作混凝土 ,常常遇到硫含量偏高 ,导致钢筋锈蚀 ,从而影响煤矸石混凝土的推广应用。本文针对这一问题 ,介绍了加水预湿冲洗、掺入 0 2 %硅酸钠溶液和加入外加剂的措施抑制硫含量的方法。     

油罐空气泡沫产生器立管清扫口的设计补充建议

石油储罐空气泡沫产生器的立管设计中,规定在管下部设锈渣清扫口,但没有具体尺寸的规定,形成了五花八门的现状,以致于有的企业在火灾扑救时出现问题,本文对锈渣清扫口设计提出具体补充意见。     

Formation of the Fe(II-III) hydroxysulphate green rust during marine corrosion of steel associated to molecular detection of dissimilatory sulphite-reductase

Accelerated corrosion phenomena of carbon steel constantly immersed in seawater could be simulated in situ via a galvanic coupling of the samples with steel port structures. Three harbours located on different seas and various conditions of immersion were considered so as to study the eventual correlation between dissimilatory sulphite-reductase genes and sulphate-containing corrosion products. In each case, after 6 or 12 months, the rust layers proved to be made of an inner black layer, close to steel surface, and an orange outer layer. Scanning electron microscopy, chemical analyses by inductively coupled plasma/atomic emission spectroscopy, X-ray diffraction and micro-Raman spectroscopy were used to obtain a detailed characterisation of these layers. The inner one proved to be mainly composed of iron sulphides FeS and Fe(II-III) hydroxysulphate green rust , the outer one of Fe(III) oxyhydroxides, with lepidocrocite γ-FeOOH as a major component. The molecular detection of dissimilatory sulphite-reductase, the key enzyme in dissimilatory sulphate reduction by micro-organisms, was applied for the first time to rust layers. This detection was positive in most cases, especially for the inner part of the rust layers. This demonstrates that sulphate reducing bacteria are associated to inside the rust layers, more likely playing the role of a source of sulphate. The systematic presence of iron sulphides also testifies the activity of sulphate reducing bacteria and/or thiosulphate reducing bacteria.