Influence of pre-treatment on the surface composition of Al-Zn alloys

The influences of pre-treatments on the composition of Al-Zn alloys, containing 0.6-1.9 at.%Zn, are investigated using scanning and transmission electron microscopies, glow discharge optical emission spectroscopy and ion beam analysis. Alkaline etching, anodic alkaline etching and electropolishing result in zinc enrichments, just beneath the oxide/hydroxide films on the alloy surfaces. The enriched alloy, about 4-5 nm thick, contains zinc in solid-solution with aluminium, up to about 18 at.%. The highest and lowest enrichments are produced by alkaline etching and electropolishing respectively. For a given pre-treatment, the enrichment increases with increase in zinc content of the bulk alloy.     

加氢工艺技术生产25#变压器油

以江苏常二线油为原料,通过加氢微型试验装置,筛选出加氢精制催化剂3996、FV-1,将上述2种催化剂按照1：1（体积比）进行组合装填,进行一段加氢法生产25^#变压器油试验取得成功,并经过了工业生产试运行。结果表明,在适宜的操作条件下,可以利用原白油加氢装置生产出合格的25^#变压器油产品,优化了装置产品结构,提高了装置创效能力。     

New ferromagnetic material based on ZnSiAs2 containing manganese

Bulk and film samples of manganese-doped zinc-silicon diarsenide are obtained. Investigation of electrical and magnetic properties of ZnSiAs₂: Mn samples showed that they possess the combination of ferromagnetic and semiconductor properties at above room temperature and are of interest as materials for spin transport.     

TiO2/α-Fe2O3复合光催化剂的制备及表征

用溶胶-凝胶法在α-FeOOH上负载TiO2,经过煅烧制备了TiO2/α-Fe2O3光催化剂.用Brunauer-Emmett-Teller(BET)法测试氮吸附比表面积.用X射线衍射、透射电镜、扫描电镜、Fourier转换红外光谱等研究了不同煅烧温度制备的光催化剂物相组成和形貌特征.研究了不同煅烧温度制备的光催化剂对活性艳蓝X-BR染料的吸附和光催化性能.结果表明:与未负载TiO2的α-FeOOH相比,经过复合、350℃煅烧制备的TiO2/α-Fe2O3复合材料的比表面积有了显著增加,从35.4m2/g增加到167.7m2/g,但是,当温度高于450℃时,其比表面积又有所下降.随着煅烧温度的增加,其负载的TiO2晶型由锐钛矿转变为金红石型,粒径也逐渐增大.在煅烧温度为350℃时,TiO2/α-Fe2O3催化剂吸附和光催化性能最好,脱色率可达到85.19%.     

Influence of Microstructure of 1050 Alloys on Electrograining in Nitric Acid

Electrograining of structurally characterised 1050 aluminium alloys in nitric acid has been examined by scanning electron microscopy. With control of alloy microstructure, particularly the size and distribution of second phase material, acceptable electrograined structures are generated with reduced power consumption. This is related directly to second phase particles providing sites in their zone of influence where pits initiate and subsequently propagate to develop the required uniformly convoluted surface.     

Fire-resistant polymer nanocomposites based on metal oxides and hydroxides

The fire-resistant properties of polymer nanocomposites based on polyvinylchloride and nanoparticles of metal compounds were studied. The investigation of nanoparticles and the determination of their sizes were carried out using scanning electron microscopy (SEM). The size of the nanoparticles of magnesium hydroxide was equal to 50–100 nm; iron oxide, 25–50 nm; and zinc oxide, 50–100 nm. Another type of fire retardant used in the work was aminotrimethylenephosphonic acid ammonium salt (AMPAS); however, the total content of the different additives did not exceed 15%. The nanocomposites obtained were investigated by means of thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC); in addition, the parameters of the oxygen index (OI) and carbon residue (CR) were measured for them. The lowest combustibility was exemplified by the composite material containing as the fire retardants a mixture of AMPAS and ZnO.     

Kinetics of phase transformations in a binary alloy surface layer at the selective dissolution. I. Theoretical analysis

A procedure of estimating the formation rate of the individual phase of an electrochemically positive component B⁰ at the anodic selective dissolution or corrosion of an A-B alloy in a potential range above the critical potential of the development of a morphologically unstable surface is proposed and theoretically founded.     

Effect of nano-sized metal compounds on the flame-proof properties of plasticized polyvinyl chloride

Based on data from thermogravimetric analysis and the oxygen index, a PVC composite containing nanosized particles of zinc oxide and amino-tris-methylenephosphonic acid has the best fireproofing indexes. The OI of this composite was 27.5%.     

水资源优化配置调度系统信息传输通道建设

监测站分中心省中心图1信息传递流程示意图2传输通道建设本系统设分中心站2个(鞍山水文分局、辽阳水文分局),端站16个。超短波电台采用进口专用数传电台,工作频率段为国家无委专为水利系统批准的230MHz数传频点。辽宁中部地区的水系主要包括辽河干流、浑河、太子河、大辽河、绕     

大系统分解协调在库群防洪优化调度中的应用

文章介绍了大系统分解协调理论,建立了串联、并联库群水库防洪优化调度模型.以澧水流域并联系统为例进行了优化调度计算,并以常规调度方案成果进行了分析比较论证.