755氧分析仪工作原理、初吹启动及事故处理

介绍755型氧分析仪的工作原理及其在实际应用中的常见故障。     

Phase Transformations in Low-Fe Alloys of the Al-Cu-Fe System

Microstructure and phase transformation in the Al-Cu-Fe alloys of the approximate compositional range of 20-50 at.% Cu and 2 - 10 Fe at.% have been investigated from samples quenched from their respective temperatures by means of different thermal analysis, magnetothermal analysis, scanning electron microscopy, electron probe analysis and powder X-ray diffraction. Representative phase transformations categorized as polymorphic, discontinuous precipitation,quasi-binary eutectoid, and ternary transitional U-type phase transformation are presented. These phase transformations were found to have a common feature which consumes the β phase and appears the φ phase. A schematic diagram was proposed to demonstrate the transition processes with decreasing temperature.     

Tween-60+Span-80/异戊醇/环己烷微乳液法制备纳米Fe3O4

采用W/O型Tween-60 Span-80/异戊醇/环己烷微乳液作为"微反应器"合成纳米磁性Fe3O4粒子。研究结果表明纳米Fe3O4粒子磁化率均随着反应温度、pH、铁离子的浓度比例ω(=[Fe2 ]/[Fe3 ])的增大先增大后减小;最优的制备条件为反应温度30℃、ω=1.2:2、pH=11。最优条件下制备的纳米Fe3O4粒子AFM图片表明所得纳米Fe3O4为均匀分散的球形微粒,平均粒径为70nm。     

使用磁性纳米颗粒检测超滤膜组件完整性实例

将已经使用54个月的自来水厂超滤膜组件不同区域的膜丝,重新组装成18个小型超滤膜组件,采用磁性纳米颗粒为标记物,通过测定超滤膜组件透过液的磁化率,判别各膜组件的完整性。结果表明,通过测定透过液磁化率指标,能够有效分辨超滤膜组件的完整性,简易方便,能够达到压力衰减测试法同样的检出精度。     

煤工业组分对磁化率影响的实验研究

煤的磁性特征在磁法探测煤火区、磁法选煤等领域有着广泛地利用.为了探究煤体磁性变化机理,选取了不同变质程度的煤样进行工业分析与磁化率测定实验,再通过用不同温度热处理的方法改变煤样原有组分,对比分析烧变煤的磁性变化,研究常温与变温条件下煤的工业组分对其磁化率的影响.     

贵州某红铁矿微波磁化焙烧试验

采用微波加热还原技术,对贵州某红铁矿进行了磁化焙烧试验,研究了焙烧温度、配碳量和焙烧保温时间对焙烧矿磁化率的影响。试验结果表明：在温度为700 ℃,配碳量为10%,焙烧时间为80 min的条件下,焙烧矿磁化率为2.324 7,接近理论值2.333 2。     

智利月亮山铁铜矿岩矿磁化率与密度关系分析

以磁性测量为主,密度测量为辅的技术方法,研究智利月亮山铁铜矿区岩矿磁化率与密度关系,认为该区岩矿可分为磁（赤）铁矿型、含铜磁铁矿型、赤铁矿（镜铁矿）型、角砾岩型,岩矿的磁化率和密度、TFe含量基本上呈正相关关系,TFe含量越大,磁化率越高,密度越大,TFe含量越小,磁化率越低,密度越小。在月亮山矿区以后的找矿工作中,对磁（赤）铁矿、含铜磁铁矿等高密度、高磁化率异常以及黄铁矿、镜铁矿等高密度、低磁化率异常进行圈定,定位找矿靶区,是一个很好的勘查手段。     

人工磁铁矿和天然磁铁矿磁性及磁选行为研究

采用振动样品磁强计和磁选管对还原焙烧人工磁铁矿和天然磁铁矿的磁性及磁选行为进行了研究,结果表明:人工磁铁矿和天然磁铁矿的磁化强度和质量磁化率随外磁场强度增大具有相似的变化规律,但前者的磁化强度和质量磁化率明显比后者小,而剩磁和矫顽力比后者大。粒度较粗时,人工磁铁矿和天然磁铁矿的磁性差异较大,而随着颗粒粒度减小,二者的磁性差异缩小。与相同粒级的天然磁铁矿相比,人工磁铁矿颗粒的磁性较不均匀,分布相对分散。粒级相同的条件下,人工磁铁矿和天然磁铁矿磁分离质效率相近,但要获得相同的分选效率,前者所需的磁场强度比后者高。通过X射线衍射分析、颗粒形貌分析和微区能谱分析探讨了人工磁铁矿与天然磁铁矿磁性及磁选差异的机理。     

Synthesis and Characterization of T1-1223 Substituted by Scandium

X-ray powder diffraction, scanning electron microscopy （SEM）, energy dispersive X-ray, electrical resistivity and AC-magnetic susceptibility measurements have been performed for polycrystalline superconducting samples of type TIBa2Ca2_xSCxCU309_δ （0.0 ≤ x 〈 0.6）. The powder X-ray diffractograms indicate that the tetragonal structure of T1-1223 is not affected by Sc-substitution whereas the lattice parameters are changed. The X-ray analysis indicates that the low-contents of scandium （x） enhance the formation of T1-1223 and reduce the secondary phases. The grain-size determined by SEM decreases as x increases. The electrical resistivity measurements show suppression in the superconducting transition temperature, Tc, and an increase in both the residual resistivity and the superconducting transition width as x increases. The suppression in Tc is attributed to the hole-filling mechanism.     

模板法制备Fe-Ni/PTFE复合膜

采用模板法和化学镀相结合的方法,初步制备了Fe-Ni/PTFE无机磁性复合膜,并考察主要影响因素:Fe2+/Ni2+、pH、反应时间、温度对其单位质量磁化率的影响,获得了制备Fe-Ni/PTFE的较佳条件。发现Fe2+/Ni2+和溶液pH对磁化率的影响比较大,引入外加电场作用后,磁化率明显增加。