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陶瓷微滤膜分离Zr(OH)4悬浮液的研究 总被引:2,自引:0,他引:2
以氯氧化锆为原料 ,氨水为沉淀剂制备超细ZrO2陶瓷微粉生成的前驱物Zr(OH) 4为微米、亚微米颗粒悬浮液 ,对于这种固液非均相物系的分离极为困难。本文采用陶瓷微滤膜新技术 ,分离该悬浮液〔1〕,实验结果表明其固液分离效率与操作性能均明显优于目前工业生产上普遍使用的各种传统分离技术 ,为陶瓷微滤膜在化学液相反应制备超细陶瓷微粉生产工艺的推广应用提供了科学依据 相似文献
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中国粉体工业发展战略 总被引:11,自引:5,他引:6
1 粉体工业范畴粉体由无数个颗粒组成 ,这里的颗粒是指在通常的操作和分散条件下不可再分的固态物质。在许多行业 ,这种颗粒状态物质俗称粉末。粉体的分类见表 1。这里需要说明的有两点 :(1)超微粉与亚微粉的界线是由显微镜下看见与否来区分的 ,而显微镜的下限在 0 .2~ 0 .8μm间 ,因此把界线划在 0 .1μm是严格的 ;②纳米颗粒是指须考虑量子尺寸效应的颗粒。量子尺寸效应和物质中许多特征尺寸有关 ,如德布洛意波长、量子 (电子波 )相干长度、隧穿势叠高度、磁畴尺寸等 ,这些尺寸各不相同 ,而且与温度有关 ,在低温下相干长度可达到1~ 1… 相似文献
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通过化学镀方法,制备了一种镀铜的聚酯微米级粉体,利用X射线衍射仪和热台光学显微镜对其表面成分和形貌进行了研究,该粉体在25℃~300℃内具有较好的热稳定性。将镀铜聚酯微粉与环氧树脂共混制备导电胶,其导电性能测试结果表明,用硬脂酸包覆处理的镀铜聚酯粉体抗氧化性好,添加质量分数为50%的硬脂酸处理镀铜聚酯微粉制备的导电胶体积电阻率为1.6×10-3Ω.cm,在25℃~120℃之内其体积电阻率变化在20%以下,是一种较好的常温导电填料。 相似文献
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《中国材料科技与设备》2012,(5):84-84
绵阳流能粉体设备有限公司长期致力于超细粉碎、分级技术与设备的开发与研制。在气流粉碎、分级技术与设备领域中的研究已走在粉体工业的前沿。公司以先进的技术,完善的设备,在粉碎、分级设备的研制与微粉加工行业中,已具有相当的专业水准。 相似文献
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A method is proposed for estimating the parameters of a mixture of exponential and Weibull distributions for which the accuracy of preliminary estimates obtained by graphical analysis is refined in accordance with the criterion of maximum likelihood. The efficiency of the proposed method is supported by the results of statistical modeling. 相似文献
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An approximate analytical expression is derived for the velocity of the front of the wave of change of boiling modes on a
rod and on a plate. The impact of the Thomson effect and of the heater orientation in the gravity field is included. Adequate
agreement is demonstrated between the derived relations and experimental data. 相似文献
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Liebert A Wabnitz H Grosenick D Möller M Macdonald R Rinneberg H 《Applied optics》2003,42(28):5785-5792
A novel method for the determination of the optical properties of tissue from time-domain measurements is presented. The data analysis is based on the evaluation of the first moment and the second centralized moment, i.e., the mean time of flight and the variance of the measured distribution of times of flight (DTOF) of photons injected by short (picosecond) laser pulses. Analytical expressions are derived for calculation of absorption and of reduced scattering coefficients from these moments by application of diffusion theory for infinite and semi-infinite homogeneous media. The proposed method was tested on experimental data obtained with phantoms, and results for absorption and reduced scattering coefficients obtained by the proposed method are compared with those obtained by fitting of the same data with analytical solutions of the diffusion equation. Furthermore, the accuracy of the moment analysis was investigated for a range of integration limits of the DTOF. The moment analysis may serve as a comparatively fast method for evaluating optical properties with sufficient accuracy and can be used, e.g., for on-line monitoring of optical properties of biological tissue. 相似文献
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水三相点是开尔文热力学温度的唯一基准点,也是ITS-90国际温标重要的定义固定点。因此,水三相点不确定度分析对整个温标的建立、温度量值传递起着至关重要的作用。近3年来,中国计量科学研究院研制出一系列高质量的水三相点容器,加强了水三相点的研究,为不确定度的分析提供了更为可靠的实验依据。同时,不确定度的分析也是客观评价新研制容器性能的一个重要指标。因此,根据实验结果对新研制容器所复现的水三相点进行了不确定度评定。评定结果表明,其扩展不确定度为0.16mK(k=2.69,P=0.99)。 相似文献
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