MPS-89N磨煤机旋转喷嘴改造节能性能分析

应用叶栅原理分析了MPS磨煤机旋转喷嘴的节能依据,根据实际运行数据,分析了磨煤机旋转喷嘴改造后的节能效果,对磨煤机旋转喷嘴的改造,不仅能改善磨煤机内部煤粉气流的均匀性,而且也有较为可观的节能效益。因此,利用此方法对MPS-89N型磨煤机旋转喷嘴的改造是成功的。     

Spectral remittances of chiral sculptured zirconia thin films in non-axial propagation

The transmission and reflection spectra from a right-handed chiral sculptured zirconia thin film are calculated using the piecewise homogeneity approximation method and the Bruggeman homogenization formalism and by considering that the dispersion of the dielectric function happens in a non-axial propagation state. First and second Bragg peaks were observed in cross-polarized reflectances and it became clear that increasing the azimuthal angle affects the spectra of the linearly polarized state significantly. This is opposite to the circularly polarized state.     

10CrNi3MoV对称球扁钢性能均一性分析

通过对连铸球扁钢横截面硬度测试、拉伸及冲击性能测试、金相组织与晶粒度的观察评定,研究了10CrNi3MoV对称球扁钢的性能均一性。结果表明,应进一步提高10CrNi3MoV性能均一性,缩小球头和腹板性能差异,改善沿轧制方向不同部位力学性能的明显差别。     

Assessment of damage in structural steels by the parameters of scatter of hardness characteristics in loaded and unloaded states

The authors discuss new experimental data on hardness of structural steels 25, 45, and 0N9, which were obtained for flat specimens subjected simultaneously to uniaxial tension, including the cases of intermittent unloading at various levels of residual strain. Based on numerous measurements (up to 30), mean values of hardness and their Gumbel scatter parameters have been determined for specimens in the loaded and unloaded states. The paper substantiates the procedure of determination of indices of sensitivity of measured hardness values and their scatter to loading conditions, which make it possible to refine the hardness characteristics as measured during technical diagnostics of equipment in operation. __________ Translated from Problemy Prochnosti, No. 3, pp. 29–37, May–June, 2008.     

温度对高精度光学玻璃折射率均匀性检测的影响

为了实现光学玻璃折射率均匀性的高精度(0.2×10-6)检测,测量环境温度引入的测量不确定度应小于0.05×10-6。对测量过程中温度引入的不确定度进行了详细分析,总结了温度引起的5种误差源,对各种误差源进行了不确定度分析。结果表明,当测量腔中空气、贴置板、折射率液及被测件的径向温差不超过±0.01℃时,温度引起的测量不确定度为0.031×10-6,满足精度要求。为实验室环境的改造提出了建议,并为高精度玻璃折射率均匀性测量提供了分析数据。     

多孔介质燃烧技术现状及发展

分析了多孔介质燃烧技术的概念,介绍了其在国内外的研究进展,并着重阐述了该技术的数值模拟和试验研究。最后对其工业应用进行了剖析。多孔介质燃烧技术在国内外的应用情况表明,该技术具有明显的节能、低排放和高供热强度的特点。宝钢使用多孔介质燃烧技术,温度均匀性好,节能10%以上,取得了显著效果,在中低温工业炉上推广应用具有广阔的前景。     

材料液滴非均匀形核时的热物理特性

建立了气相下，液滴非均匀形核时的内能，热膨胀系数的有关公式，讨论了液滴胚核热膨胀系数与其它相关物理特性之间的关系。     

Assessment of Enzymatic Endosperm Modification of Malting Barley Using Individual Grain Analyses

Enzymatic modification of the endosperm of malting barley is a main feature of the malting process. Uneven enzymatic modification of the endosperm (heterogeneity) can cause brewhouse problems. Although there is a general correlation between endosperm modification, beta‐glucan breakdown and endo‐beta‐glucanase development, it is based on average results from sample analyses and may conceal heterogeneity. The primary aim of this work was to use individual grain analyses to investigate factors that control endosperm modification and beta‐glucan breakdown. In terms of beta‐glucan breakdown and physical modification, the barley variety Chariot malted faster than Decanter. However, both varieties showed similar distribution of endo‐beta‐glucanase in individual grains during malting. Further work on individual grains showed that the correlation between beta‐glucan breakdown and endo‐beta‐glucanase activity was not significant. Surprisingly beta‐glucan breakdown did not always correlate with the physical modification of the endosperm. Both these findings suggest that sample analyses of beta‐glucan levels and malt beta‐glucanase activities are not reliable indicators of the degrees of which malt samples are modified during malting. Since the distribution of beta‐glucan in individual grains of the unmalted barley varieties was similar, the total beta‐glucan levels of the original barley did not determine the rate at which beta‐glucan was broken‐down during malting. Although protein studies are at a preliminary stage, the rate of protein breakdown was not correlated with the rate at which beta‐glucan was broken down in the malting grain. It is possible that the physico‐chemical properties of endosperm storage proteins may limit the rate of beta‐glucan breakdown during malting.     

改善高线加热炉加热质量的技术措施

针对棒线材加热炉在加热质量方面存在氧化烧损及脱碳情况方面损耗量大、加热温度均匀性差等问题,采用全平焰烧嘴、精细化供热分段等多种技术措施,达到进一步改善棒线材加热炉加热质量的目的。     

提高石英砂均匀性的改造

玻璃生产中石英砂的均匀性对稳定玻璃熔窑的热工制度、提高熔窑熔化量和质量起着重要的作用。通过对石英砂的投入前、投人过程、投入后的改造,实现了石英砂均匀性的提高效果。