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无机非金属材料专业实验是无机非金属材料专业必修的一门实验课,而真密度的测定是其中的一个基本实验。测定真密度,对于判断石英转变为方石英和鳞石英的程度,镁石再结晶为方镁石的程度,氧化铝的晶型转化程度以及在进行粘土或坯料的颗粒分布测定、球磨泥浆细度的快速测定等都需要真密度的数据。采用比重瓶法测定粉料的真密度,在实验过程中,由于比重瓶内部被水打湿(按原步骤)且瓶口较小,倒粉料人瓶时会粘在比重瓶的内壁且操作不慎粉料会撒在瓶外,导致所称粉料的重量与实际不符,如果返工, 相似文献
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比重瓶法与密度仪法测定香精密度相关性的回归分析 总被引:1,自引:0,他引:1
目前测定香精密度的方法主要有标准传统法-比重瓶法和密度仪法。用这两种方法测得的结果一致与否,为探求这两者之间相关关系的密切程度和表现形式,通过测定系列香精的密度,并对所得数据进行线性相关和回归分析,得出了比重瓶法与密度仪法所得结果的相关方程。利用该方程可以由密度仪法测得的结果计算出比重瓶法的密度,经计算出的结果与标准方法比较一致。通过回归方程,可以用密度仪法代替标准法来测定香精的密度。 相似文献
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本文依据GB/T 1033.1-2008《塑料非泡沫塑料密度的测定第1部分:浸渍法、液体比重瓶法和滴定法》分析了PVC-U管材密度测量不确定来源,并对其进行了测量不确定度评估。 相似文献
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A new method has been developed for the evaluation and comparison of quality of various types of poly(vinyl chloride) (PVC) powder with respect to their density homogeneity. The method consists in the determination of the dependence of the volume of a specifically heavier fraction of PVC powder on the density or concentration of testing aqueous NaNO3 solutions after a chosen time of contact between the powder and the testing solutions. Compared with the method of determination of density distribution using densitometric titration, the new method simplifies and extends possibilities of comparison of polymers and improves the density characterization. 相似文献
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建立了用高效液相色谱(HPLC)/二极管阵列检测器(DAD)同时检测粉状化妆品中多种有机着色剂的检测方法。样品采用甲醇+水(1:1)提取溶剂超声提取15min后,以乙腈-磷酸二氢钾缓冲溶液(pH=6)为流动相梯度洗脱,在240nm的波长下用DAD对9种目标物同时进行检测。用保留时间结合目标化合物的紫外吸收光谱定性,外标法定量。方法的平均回收率(n=9)在90.31%-99.10%的范围内,精密度RSD在1.95%-4.61%之间。方法简单、快速,能有效提取和分离测定粉状化妆品中多种有机着色剂。将该方法用于实际样品的检测,结果令人满意。 相似文献
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In this study, soymilk powder was produced by spray drying. The inlet air temperature of spray dryer was varied from 200 to 280°C and the feed concentration was varied from 15 to 25% (w/v). Response surface methodology was used to examine the effects of these independent variables on the detailed characteristics in terms of physical, structural, functional properties of powder. Overall, results show that rising the inlet air temperature caused a decrease in tapped and loose bulk density, true density, filling rate, water holding capacity, and water content of powder; and an increase in compressibility, Hausner ratio, porosity, interstitial air volume, and wettability index. An increase in feed concentration led to an increase in true density, compressibility, Hausner ratio, porosity, interstitial air volume, and wettability index; and a decrease in tapped and loose bulk density, filling rate, water holding capacity, and water content; whereas oil holding capacity might be increased or decreased and it depended almost solely on the feed concentration. 相似文献
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研究了球磨粉的特点和普通球磨粉与超细粉的差别,并根据不同粒度焦炭的吸附性计算出其粘结剂的最佳需要量。结果表明,-0.075mm球磨粉需要粘结剂量是2~1mm焦炭需要粘结剂量的3.8倍,是4~2mm焦炭需要粘结剂量的4.2倍。同时还计算了由不同粒度焦炭构成的糊料的真密度,-0.075mm球磨粉构成糊料的真密度低于0.5~0.15mm及0.15~0.075mm焦炭构成糊料的真密度,但明显高于4~2mm焦炭构成糊料的真密度。-0.075mm球磨粉的含量对炭素制品的性能有明显的影响,其含量适宜时,炭素制品的体积密度、抗折强度及弹性模量最高,电阻率最低。 相似文献
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就氦气替换法测定煤的真相对密度进行了研究。6个国家一级标准煤样的测定值都在标准值的不确定度范围之内;方法的准确度与国家标准方法没有偏倚,精密度与国家标准规定一致。 相似文献
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Jia Wang 《Journal of the American Ceramic Society》1992,75(9):2627-2629
Sintered Y-TZPs formed using cold isostatic compaction exhibit a lower sintered density and more porosity than ceramics formed using conventional uniaxial die compaction, although the isostatically pressed powder compact has a higher and more uniform green density. For the 3 wt% PEG1500-doped zirconia powder, the sintered density decreases in a near-linear manner with increasing isostatic pressing pressure. It was identified that the low sintered density and the poor microstructure were due to the incomplete burnout of PEG1500 at the low and intermediate temperatures when the powder compacts were heated at a rate of 3°C/min. The delayed organic burnout at temperatures close to and/or at the sintering temperature results in the formation of largely swollen intergranular pores. 相似文献
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探索了一条高固含量推进剂较安全的成型工艺路线,重点介绍了一种高固含量球形药工艺.采用内溶法制得纯硝化棉黏合剂体系及硝化棉与ETPE(含能热塑性弹性体)混合黏合剂体系的高固含量(RDX(黑索今)质量分数为55%~60%)球形药,其球形药密度接近理论计算值,颗粒饱满,粒度均匀致密.采用模压成型工艺将其压制成推进剂药柱,药柱经无损检测,均匀致密,内部无气孔.同时药柱进行了各项性能实验.研究结果表明:该工艺方法简单可行,安全可靠. 相似文献