Production of surface-active sophorolipid biosurfactant and crude oil degradability by novel Rhodotorula mucilaginosa strain SKF2

Biosurfactants are produced by important types of microorganisms such as bacteria, yeast, and filamentous fungi and have been used in a variety of industries. Among the 15 crude oil-degrading fungi, the two molds and one yeast were identified by 18S rDNA sequences as Mucor circinelloides strain SKMC, Fusarium fujikuroi strain DB2, and Rhodotorula mucilaginosa strain SKF2. These strains were isolated from crude oil–contaminated soil, diesel oil–contaminated soil, and activated sludge in the Oil Refinery Plant in Isfahan, Iran, respectively. The yeast strain was identified as a novel crude oil–degrading and biosurfactant-producing fungi in the presence of (1% v/v) Iranian light crude oil in the minimal salt medium (MSM). The highest amount of the dry weight of produced biosurfactant was measured at 6.2 g L⁻¹. Chemical nature of produced biosurfactant was determined as a surface-active sophorolipid biosurfactant compound by thin-layer chromatography, Fourier transform infra-red spectroscopy, and gas chromatography–mass spectrometry (GC–MS) analysis. The residual hydrocarbons in the MSM were analyzed by GC–MS, and it was shown that octadecane and docosane were eliminated by this novel strain completely.     

SKF滚动轴承仿真技术进展

SKF公司与PEIAB合作开发的BEAST滚动轴承仿真软件使滚动轴承动力学仿真设计真正变成现实，并应用于轴承新产品的开发当中。着重介绍仿真软件BEAST数学模型和特点，以及仿真结果的实验验证。     

SKF炉精炼钢中Als含量对夹杂总量的影响

对ＳＫＦ精炼炉中Ａｌｓ的含量与夹杂一的关系进行了研究,研究了当Ａｌｓ在０．０１５％￣０．０３０％的范围时,可以有效地控制夹杂总量,提高钢的纯净度。     

马钢SKF炉精炼渣工业性试验研究

研究分析了马钢ＳＫＦ钢包精炼炉精炼渣操作存在的问题,提出了优化的精炼渣系。工业试验结果表明,优化后的精炼渣系熔点低、流动性好,冶金效果显著,对包衬有显保护作用。     

现代细纱牵伸装置的技术进步与专件、器材的发展

在分析SKF型牵伸、HP型牵伸、R2P型牵伸和INA-V型牵伸的结构特点和技术进步的基础上，指出现代牵伸装置的技术进步主要体现在牵伸专件、牵伸器材的发展上。通过对各种牵伸加压摇架的性能进行比较，推荐独立气囊直压式气压摇架是今后发展方向。指出通过引进、消化、研制和创新，我国的牵伸专件和器材的使用性能基本上已达到现代水平，但其中关键器材胶辊的使用寿命仍有相当大的差距。     

浅析一钢SKF加热工位设备搬迁的可行性

马钢计划将原一钢厂SKF炉加热工位和真空泵系统搬迁到三钢厂。本文通过对SKF炉加热工位主要工艺设备的分析核算 ,证明SKF加热工位的主要工艺设备在理论上可以搬迁利用。     

Frictional power loss in solid‐grease‐lubricated needle roller bearing

The use of solid grease as a lubricant, in comparison with standard grease or oil, is a pre‐requisite when needle roller bearings undergo a high‐speed oscillating motion and when access to the bearing is difficult for maintenance purposes. This paper examines the frictional power loss of a solid‐grease‐lubricated needle roller bearing. First set of measurement result reveals that the test bearing has higher frictional power loss as compared with other bearings with conventional lubrications, due to the high viscosity of the solid grease. Furthermore, measurements are compared with the Palmgren and SKF models. For improving these models, the parameters of the models are updated on the basis of the measurement data. A second set of measurement result shows that the use of oil (kept at higher temperature) in addition to solid grease significantly reduces the frictional power loss. The reduction is due to the decrease in operational viscosity of the solid grease. Copyright © 2012 John Wiley & Sons, Ltd.     

SKF炉精炼钢中Als含量对夹杂总量的影响

对ＳＫＦ精炼炉中Ａｌｓ含量与夹杂总量的关系进行了研究，确定了当Ａｌｓ在０．０１５％～０．０３％的范围时，可以有效地控制夹杂总理，提高钢的纯净度。     

SKF炉电磁搅拌系统的切换改造

分析了马钢一钢厂SKF炉电磁搅拌系统的运行现状及问题,为加强安安可靠性,提出了增加切换装置变频器互为备用的改造方案,简要介绍了主回路和控制回路的改造方案。     

JF型细纱牵伸形式、工艺及其成纱质量

介绍了细纱牵伸的主要形式和采用摇架加压的JF型双短胶圈牵伸装置,说明其适应前区小隔距、小浮游区、强控制的牵伸工艺,纺纯棉的成纱质量指标得到全面提高,并且机构简洁,操作方便,成本降低。