共查询到20条相似文献,搜索用时 156 毫秒
1.
2.
3.
4.
以钛酸四丁酯与醋酸钡为钛酸钡前驱体,PEG为分散剂,硝酸钐为掺杂物种给体,采用溶胶-凝胶法制备改性的Sm掺杂BaTiO3纳米粉体。样品经X射线衍射(XRD)与差热-热重联用(DSC-TGA)的方法对其进行了表征。研究了煅烧温度与分散剂对BaTiO3粉体粒径与相的影响。结果表明:立方相在700~850℃生成,前驱体经950℃热处理制得后呈四方相BaTiO3。分散剂PEG可抑制BaTiO3晶粒增长;随煅烧温度升高,粉体粒径增大。适量Sm掺杂可以抑制杂质BaCO3相的形成。 相似文献
5.
6.
7.
8.
采用溶胶-凝胶法,以菱镁矿、盐酸和尿素为原料,加入成胶剂聚乙二醇制备纳米氧化镁。考察了煅烧温度、成胶剂分子量、分散剂及其用量对实验的影响。结果表明,制备纳米氧化镁的适宜条件为:以10 000分子量聚乙二醇为成胶剂,1.5%的PVT-1为分散剂,煅烧温度为650℃。在此条件下,可获得纯度98.5%,平均粒径小于100 nm,呈近球形均匀分布,活性良好的纳米氧化镁。 相似文献
9.
10.
本文介绍了泡沫凝胶注模成型工艺,研究了分散剂、固相含量等工艺参数对浆料粘度的影响,研究得出浆料中固相含量为55%时,以PMAANa为分散剂,可获得100 mPa·S低粘度高固相的陶瓷浓悬浮液;同时还研究了引发剂对凝胶固化反应的影响,实验结果表明引发剂在0.3~0.4%时聚合时间较适宜;重点探讨了发泡剂、固相含量、引发剂等对多孔氧化铝陶瓷性能的影响。 相似文献
11.
12.
13.
14.
15.
16.
采用傅里叶变换衰减全反射红外光谱法(ATR-FTIR)研究了分散剂官能团特征与神府煤(SFC)成浆性匹配规律。基于4种分散剂的ATR-FTIR分析结果,采用Gaussian分峰法计算了这些分散剂中亲水基团(-OH、-C-O、-C=O、-SO3-)和疏水基团(-CH3、CH2、-C=C)的分布,研究了分散剂中亲、疏水基团对神府煤成浆性的影响。结果表明:用ZFZ分散剂所制备的神府水煤浆(SFCWS)的定黏浓度最高,用MZS分散剂制备的SFCWS的浓度最低。这主要归因于ZFZ分散剂有较多的亲水基团,相对较少的疏水基团,与神府煤有良好匹配性。采用偏最小二乘法(PLS)建立了分散剂与神府煤定黏浓度预测模型和匹配度模型,选用JJN、DNC和SMS分散剂验证了模型的精确性,误差在±1%以内,同时定黏浓度预测值和匹配度的预测值与定黏浓度的实验值变化趋势一致。 相似文献
17.
《Journal of the European Ceramic Society》1999,19(4):479-488
Acoustophoresis was used to study the effect of adding various commercially available dispersants onto aqueous suspensions of two zirconia and two titania powders. These powders were characterised for elemental composition by X-ray fluorescence (XRF) spectroscopy and for surface area by BET single point nitrogen adsorption. From the maximum value of the zeta potential, it was possible to select the most promising dispersants. From the shape of the curve the minimum amount of dispersant required to stabilise the powder particles was noted. The iso electric point (i.e.p) of the powders was also identified. Several dispersants can be recommended for the first titania powder, whilst none can be recommended for the second titania as the final zeta potentials on addition of the dispersants were low. The two powders had different surface chemistries which was reflected in a large difference in their i.e.p; the first at pH 7·5 and the second at pH 6·1. This was due to different coatings on the powder surfaces; alumina and an organic material respectively. Removal of this organic coating by calcinatian then enabled the dispersants to fully adsorb. Similarly dispersants for the first zirconia powder could be identified and the i.e.p identified at pH 5·4. However, no dispersants can be recommended for the second zirconia powder as yttria dissolves out of the powder under the naturally occurring weakly acidic conditions. The i.e.p was estimated to be pH i.e.p 7–7·5. 相似文献
18.
不同分散剂对纳米白炭黑的改性研究 总被引:2,自引:0,他引:2
在沉淀法制备白炭黑的过程中对白炭黑直接进行湿法改性,选用丙三醇、正丁醇、聚乙二醇-6000及其并用作为分散剂进行湿法改性,采用X射线衍射(XRD)、扫描电子显微镜(SEM)、Fourier红外光谱分析仪(IR)、HG/T 3062-2008标准测定吸油值(DBP值)对实验制得样品进行表征。研究了不同分散剂对沉淀法白炭黑的分散性、粒径、结构、表面形貌等性能的影响。结果表明:采用单一改性剂丙三醇、正丁醇、聚乙二醇-6000时效果不佳,将其中两种并用其改性效果提高,将三种分散剂并用效果最为明显。 相似文献
19.
在纯溴化锂溶液中加入纳米微粒或分散剂,对比测试其与纯溴化锂溶液的表面张力和沸腾温度的数据,并从所用分散剂的分子结构和纳米微粒的尺寸及外部轮廓的角度出发,定性推测不同种类分散剂及纳米微粒对溴化锂溶液表面张力和沸腾温度的影响.试验发现,添加分散剂溶液的表面张力明显降低,其沸腾温度也相应减小;固体纳米微粒因其填充加热表面凹坑使溶液的沸腾温度有所升高.对于加入纳米微粒及其分散剂的溴化锂溶液,溶液表面张力衰减的正效应因素和纳米微粒填充凹坑的负效应因素的耦合影响将对其沸腾温度产生重要影响. 相似文献