新冶钢Assel轧管机组的现状与未来发展战略

介绍了湖北新冶钢有限公司4套Assel轧管机组和2条热处理生产线的概况,着重阐述了机组工艺装备、产品定位、工艺流程及其特点;提出了在当前及今后相当长时期内,面对国内外严峻的市场形势和激烈的市场竞争,应坚持的品种研发方向和应采取的市场开发策略。     

Low-cycle fatigue strength of 10GN2MFA steel with a single-layer corrosion-resisting coating produced by electroslag strip cladding

The method of testing the uniform single-layer corrosion resisting coating, produced by electroslag strip cladding on 10GN2MFA steel, on the resistance to low-cycle fatigue strength using special specimens is described. Tests were carried out at a temperature of 20 °C with the symmetric axial tension–compression loading cycle (R_e = –1) with the given amplitude of the parent and cladding metal. The tests were carried out in the strain amplitude range ε_a = 0.28–0.8%, the number of cycles to the initiation of a crack was N_i = 340–16,000 cycles, loading frequency f = (0.25–2.0). The area of formation of the cracks was recorded in the experiments. In most cases, the cracks formed in the heat-affected zone in the vicinity of the fusion line and propagated in both the parent and deposited metal. The results show that in the range of low-cycle fatigue for the investigated 10GN2MFA steel with a deposited layer, the calculation coefficient of the decrease of the cyclic strength of the metal with a deposited layer in relation to the fatigue curve for the carbon and alloyed steel with 0.8 ≤ σ_0.2/σ_B ≤ 0.9, the value φ_S = 0.68 should be used in the calculations.     

A comparative analysis of experts’ and consumers’ perceptions of regionality in Australian wine purchase decisions

This study provides insight into consumers’ perception of regionality when purchasing regional wine in terms of regional specialisation for style, volume of production of the wine style, quality of the wine, heritage of the wine region and the distinctiveness of the wine styles produced in the wine regions of Australia. Data were collected from 203 Australian wine consumers through an online survey. The study compares the results of this study with Easingwood et al. [2011. The drivers of wine regionality. Journal of Wine Research, 22(1), 19–33.] study on experts’ opinion of regionality drivers. This paper will expand knowledge on how consumer involvement levels impact decisions relating to purchasing regional wine. This study is of value to academics and wine practitioners alike. It contributes to the wine literature by providing a new perspective on consumers’ perception and draws attention to the risk of drawing conclusions about wine consumption based on experts’ opinions as being reflective of the average consumers’ purchase decision-making.     

对国产塞曼原子吸收分光光度计仪器稳定性与数据重现性考察

本文通过对国产塞曼原子吸收分光光度计一段时间的使用与实际测量后,着重介绍了两个考察仪器性能的实验,一是开机不预热的长时间静态基线稳定性实验;二是长时间、多元素、混合测量的数据重现性实验。特别是实验二,是8小时的连续工作、多任务多元素的混合测量、关机后第二天的继续测量、以及若干天后的再次测量等,而确立的有针对性的考察数据能否稳定重现的实验,能够反映用户在实际使用中诸多常见的工作情况,具有一定的参考价值,从一个侧面反映了现有国产塞曼原子吸收仪器的可靠性能,得到了满意的结果。     

层次分析法在手机品牌比较中的应用

针对中国手机市场的激烈竞争现状,首先通过调查和分析市场相关因素并结合相关定性分析方法,确定了影响手机顾客消费的指标体系,然后利用层次分析法来定性和定量地分析手机的影响因素并确定各因素影响手机顾客消费的权重大小,最后提出了一种手机品牌的比较方法,同时指出此方法可扩展到其他产品.     

Thermally grown oxide scales on γ-TiAl coated with thermal protection systems

Abstract

Thermal barrier coatings (TBCs) of yttria partially stabilized zirconia were deposited on gamma TiAl samples using electron-beam physical vapour deposition. The specimens were coated with intermetallic Ti –Al – Cr layers and CrAlYN/CrN nanoscale multilayer coatings. The lifetime of the TBC systems was determined performing cyclic oxidation tests in air at temperatures between 850 and 950–C. The TBC systems with Ti –Al – Cr and CrAlYN/CrN layers did not fail at 850 and 900–C during the maximum exposure time period of 1000 cycles of 1 h dwell time at high temperature. No spallation of the thermal barrier coatings was observed. As revealed by post-oxidation microstructural analysis, the protective coatings were severely degraded when exposed at 900–C, resulting in growth of mixed oxides on the substrate. Underneath the thermal barrier coating an outer oxide scale with a columnar structure was observed, consisting of rutile and α-Al₂O₃. Energy-dispersive X-ray spectroscopy analysis revealed zirconia and chromia being dissolved in the outer oxide scale. The columnar structure and the presence of zirconia indicated an effect of the TBC on the morphology of the outer oxide scale. The zirconia top coat exhibited an excellent adherence to this oxide scale formed on the protective layers when degraded, and at defects like cracks. When thermally cycled at 950–C, the TBC system on specimens coated with Ti –Al – Cr failed by spallation of the thermally grown mixed oxides, whereas the thermal barrier coating was well adherent to the outer oxide scale at this temperature, too.     

Studies on structural and electrical properties of copper-doped zinc oxide powders prepared by a solid state method at high temperatures

Abstract

The synthesis, crystal structure and electrical conductivity properties of Cu-doped ZnO powders (in the range of 0.25 – 15 mole %) is reported. I-phase samples, which were indexed as single phase with a hexagonal (wurtzite) structure in the Cu-doped ZnO binary system, were determined by X-ray diffraction. The limit solubility of Cu in the ZnO lattice at this temperature is 5 mole % at 1000°C. The impurity phase was determined as CuO when compared with standard XRD data using the PDF program. We focused on single I-phase ZnO samples which synthesised at 1000°C because the limit solubility range is widest at this temperature. It was observed that the lattice parameters a increased and c decreased with Cu doping concentration. The morphology of the I-phase samples was analysed with a scanning electron microscope. The electrical conductivity of the pure ZnO and single I-phase samples were studied using the four-probe dc method at temperatures between 100 and 950°C in an air atmosphere. The electrical conductivity values of pure ZnO and 5 mole % Cu-doped ZnO samples at 100°C were 2 × 10^?6 and 1.4 × 10^?4 ohm^?1 cm^?1, and at 950°C they were 1.8 and 3.4 ohm^?1 cm^?1, respectively. In other words, the electrical conductivity slightly increased with Cu doping concentration. Also, it was observed that the activation energy of the I-phase samples was decreased with Cu doping concentration.     

Composite portraiture in New Zealand

Abstract

Composite portraiture has a long history which is not, of course, confined to this country, but it flourished here to a significant and, perhaps, astonishing degree during the 19th century. The purpose of the composites was usually commercial. Members of a congress might be so portrayed in collective fashion, or else a professional portrait photographer might take advantage of his accumulated files and issue a composite as his firm's advertisement. In this fashion the Burton Brothers of New Zealand made a fascinating composition between 1867 and 1877, which has already been published in another context¹ , but is here reproduced for easy reference (Figure 1). The firm's shop-front is shown in the centre with the two photographers on either side. Above the shop-front are portraits of Captain Cook, Captain Cargill (the leader of the Otago settlement), Queen Victoria (the royal patron of the firm), and julius Vogel (the Premier of New Zealand in 1873), together with local administrators and other dignitaries. In the top corners are the bishops of the Anglican and Roman Catholic churches; below are the wives of the photographers. There are some 785 portraits in all. There is also, woven into the composite, the wording ‘hotography Burton Bros Dunedi’ which has been cut out and superimposed on the pasted-up portraits. Closer inspection reveals much humour. Under the words ‘Burton Bros’ are two photographs of seances or ghost pictures. In the ‘U’ of the word ‘unedi’ Alfred Burton himself appears, dressed up as Uncle Sam. A man who is thought to be Walter Burton appears in a nightshirt between the ‘I’ and ‘N’, and he is certainly the figure making strange gestures in two shots beyond the ‘N’. Between the ‘N’ and ‘E’ Alfred again appears, dignified in Masonic dress, while an adoring female worships him from the proximity of the adjacent ‘N’. A dog even turns up between the ‘H’ and ‘Y’ of the word ‘hotograph’. An interesting feature is the photographic caricature of a man with a large head on a small body, reminiscent of an 1876 example shown by Gaston Tissandier, who also gave some rather obvious instructions to enterprising montage artists: To represent a large head on a small body a picture of the head alone is first taken and then a picture of the entire body on a much smaller scale. Proofs are taken on paper from the two negatives, and then the large head is cut out and pasted on to the shoulders of the figure on the smaller scale. If the large head does not fit very well on to the small body the neck is touched up with a brush. A photograph is then taken of the picture thus obtained, and the negative produced will furnish any number of caricature proofs². For sheer photographic fun, the Burton work is an outstanding example of its kind.     

浪形保持架整形凹模加工工艺改进

浪形保持架整形凹模在等分车床上加工时,由于加工精度低,达不到使用要求,选择在镗铣加工中心加工,既减少了加工工序,又提高了模具的精度和寿命,提高了生产率。     

单层钢结构厂房板件宽厚比限值的选用分析

在单层钢结构厂房设计中,合理选用钢构件宽厚比限值,对厂房的单位耗钢量有很大的意义。为此,GB 50011—2010《抗震规范》引入了"抗震性能化设计"的设计原则,对钢结构设计提出了"高延性-低弹性承载力"和"低延性-高弹性承载力"两类思路。通过计算比较的方式确定板件宽厚比,使设计更加合理。通过解读GB 50011—2010中的相关条文并通过实例计算,以期对设计者在进行单层钢结构厂房设计时选用合理的设计方法提供参考和帮助。