Investigation of Centreline Segregation and Centreline Porosity in CC ‐ Slabs

Improvements of solidification processing in conventional or near net shape casting depend on sophisticated methods of macroscopic examination of central unsoundness and inhomogeneity of the cast material. As long as remarkable deviations referring to the quality features exist between the slab centre and the bulk material such methods should be looked after. Two semi‐macroscopic methods of segregation analysis are discussed in this paper: firstly, the potential of the emission spectral analysis combined with sectioning of a sample and secondly, the computer aided micro‐probe analysis. Both methods are restricted to small local areas. The proneness of elements and steel grades with respect to micro‐ and macrosegregation as well as distribution‐ and segregation coefficients are determined. The effect of a diffusion anneal on homogenisation of segregation is studied. Last not least the precipitation of sulphides, phosphides or carbonitrides is estimated. Ultrasonic detection of the central unsoundness of conventional slabs or thin slabs is a new approach towards a quantitative macroscopic examination. The sample size is 400 mm x 300 mm x 30 mm. To achieve a low ultrasonic noise using a 5 MHz‐transducer the samples are heat treated for grain refinement. “Dog bone porosity”, macroscopic topographical misfit between the upper and lower solidifying shells, periodical corner cracks or systematic transverse centre cracks are detected. Obviously, segregations do not reflect the ultrasonic beam. However, it can be presumed that an interrelation exists between porosity and segregation, although these might be locally apart from each other. This new ultrasonic test of the central unsoundness of continuous cast (c.c.) slabs gives valuable arguments to machine builders and maintenance people to decide on the right concepts for strand guidance, support rollers and secondary cooling. Soft reduction can be optimized and variations in casting speed counteracted by dynamic means. R&D service of this kind can help steelmakers when decisions are impending to build new casting machines or revamp old ones.     

RD取样器及其应用

RD取样器是在APR-M2工具基础上发展起来的专用取样设备，由取样心轴、取样外筒、破裂盘、样品腔几部分组成。与RD安全循环阀配合使用，完全可以替代APR-M2工具，具有取样准确、缩短施工工期，取样过程简单、安全等特点。     

矿石中金的快速测定

研究了活性炭纤维滤布富集分离的条件和解脱方法,并利用微波溶样、液珠萃取比色法测定矿石中的金。该方法的测定范围为(0.5~xx)×10-6,相对标准偏差RSD为3.2%,可用于矿石中金的野外快速测定。     

综合应用地震属性、测井数据反演储层参数

本文研究了样点地震属性的特征提取，利用BP神经网络建立测井声波时差和地震属性的非线性映射关系。采用距离加权平均对研究区所有井的反演结果进行外推。为了提高分辨率和计算结果的准确性，详细分析、研究了适合于地震信号分解和重构的小波，以及测井声波时差和地震波阻抗与层界面的关系。最后，对反演的声波时差资料进行界面影响校正，进而计算出较符合实际情况的孔隙率参数。经已知井和新钻井验证，计算结果和实际情况相一致，效果令人满意。     

Direct preparation of particles from liquid suspension for ESEM or SEM analysis

A simplified method for the preparation of particles from liquid suspensions has been developed. Particles are deposited directly on carbon planchets for rapid analysis by environmental scanning electron microscopy or by conventional scanning electron microscopy after an additional drying step. This is accomplished by filtering the liquid through thin carbon planchets. Three different grades of graphite were investigated for their suitability as the source material for these planchets. The high quality isomolded graphite is recommended for the filtration and direct observation of particles by electron microscopy. This technique is demonstrated for particles in hydraulic fluid and aquatic suspended particulate material from a natural water source.     

Use of the Extreme Groups Approach: A Critical Reexamination and New Recommendations.

Analysis of continuous variables sometimes proceeds by selecting individuals on the basis of extreme scores of a sample distribution and submitting only those extreme scores to further analysis. This sampling method is known as the extreme groups approach (EGA). EGA is often used to achieve greater statistical power in subsequent hypothesis tests. However, there are several largely unrecognized costs associated with EGA that must be considered. The authors illustrate the effects EGA can have on power, standardized effect size, reliability, model specification, and the interpretability of results. Finally, the authors discuss alternative procedures, as well as possible legitimate uses of EGA. The authors urge researchers, editors, reviewers, and consumers to carefully assess the extent to which EGA is an appropriate tool in their own research and in that of others. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

可节约生产成本的湿处理工艺技术

从传统意义上来讲，针织物及对张力敏感的梭织物的湿处理生产线（包括漂白、染色、柒色后水洗）通常是利用染缸来完成的，而这正是高水耗、高蒸汽消耗和高能源消耗的症结所在，同时带来一些质量问题（如折痕、起毛球和刮印等）。随着现代连续式平幅湿处理线技术的发展，整体生产成本可以下降到最多这50％。介绍了德国欧宝泰克生产的敏感织物连续式平幅湿处理线设备。     

钼酸铵溶液深度净化工艺探索

对传统的钼酸铵溶液净化工艺及文献介绍工艺进行了较为详细的分析 ,并与实验数据对比分析 ,找到了较为合理的工艺方案