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以硫酸钛的水溶液为原料,加尿素作添加剂(尿素与Ti4+摩尔比1:5),较低温度下用水热法在玻璃基板上制备了TiO2微米球,结果显示生成的TiO2晶体为锐钛矿型.并讨论了形成微米球的机理. 相似文献
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由于中空球结构材料的中空部分可容纳大量的客体分子或大尺寸的客体,从而产生一些奇特的效应,使得对中空结构材料的研究成为目前材料学领域中的热点,但以无机盐作壳材料制备中空球的研究却未见报道.以氯化钠作壳材料制备中空球,不仅拓展了对中空球材料的研究范围而且对工业生产也提供了有力的实例.将氯化钠与表面活性剂配制成溶液,通过喷雾干燥得到氯化钠的粉末.用Scott漏斗法测定了粉体的表观密度,大约为0.3 g/mL.用偏光显微镜测定了粉体的粒径,通过 XRD和SEM对粉体的晶型和形貌特征进行了分析,确认所得粉体颗粒由简单立方型氯化钠晶粒组成且粉体粒子具中空状球形结构. 相似文献
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引言在型焦与大型煤砖制造新的发展下推动了燃料制球的发展,就要求对粘结剂作一新的浏览,本文是作者关于粘结剂的概况与新发展的一个综论。 相似文献
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比较了制取聚合物微球的方法,指出了传统悬浮液聚合技术制备小白球的不足,并对喷射聚合小白球的生产工艺装置作了改进。 相似文献
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以硝酸镍为镍源,浓氨水为沉淀剂,水热法合成了花瓣状β型氢氧化镍球和β型氢氧化镍纳米片,其合成方法简单易行。采用XRD和SEM分别对合成的样品进行物相和形貌分析。结果表明:在相同的pH和反应时间条件下,低温下有利于合成花瓣状β型氢氧化镍球,高温下有利于合成β型氢氧化镍纳米片。即当反应时间为48.0 h、pH=9.0时,180℃下合成了花瓣状β型氢氧化镍球;240℃下合成了β型氢氧化镍纳米片。通过考察水热条件对产物形貌的影响,探讨了花瓣状β型氢氧化镍球和β型氢氧化镍纳米片的形成机制。 相似文献
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微囊化载药高分子微球制备方法研究进展 总被引:4,自引:0,他引:4
本文综述了各种微囊化制备微球的方法和原理,并对微囊化微球技术的研究最新进展及其在纳米微球,磁性高分子微球、智能微球制备上的应用作了介绍。 相似文献
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球磨机研磨体合理的级配,对提高磨机产量和产品质量、降低粉磨电耗,具有重大的作用。在总结几百家水泥厂磨机工艺技术员工作经验的基础上,根据笔者长期从事物料粉磨研究和实践的心得体会,综合考虑研磨体总装载量、各仓填充率、平均球径、物料水分、物料流动性、物料粒度、隔仓板形式、隔仓板篦缝大小、各仓长度、粉磨流程等因素,详细介绍了球磨机研磨体级配计算的方法、原理和步骤,并编制成“球磨机研磨体级配及补球计算程序”软件。 相似文献
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针对热解炭颗粒大、表面活性弱、吸附能力差的问题,本文提出了一种机械球磨表面改性方法,探讨了不同球磨改性参数下热解炭对磺胺甲唑(SMZ)的吸附效果。以废橡胶连续热解炭为原料,采用不锈钢球磨制得具有不同表面性质的球磨炭,分析了球磨前后热解炭的结构、表面性质及表面形貌,并对比了球磨改性前后的SMZ吸附性能。结果表明,球磨改性过程可以有效改善废轮胎热解炭结构及表面性质,球磨处理2h的热解炭对SMZ的吸附效果最好,吸附量达到59.37mg/g,吸附动力学符合伪二级吸附模型。 相似文献
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肖炳荣 《现代塑料加工应用》2003,15(5):32-34
从型材内筋壁厚、加工助剂、辅助原料、塑化控制、模具流道等方面分析了PVC型材低温落锤破裂影响因素,并提出了提高PVC型材低温落锤冲击性能的建议。 相似文献
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Flaky metal powders commonly used as paint and pigments, are generally produced by grinding in ball mills or vibration mills. The key to good quality powder production is to optimize the processing parameters. In the present work grinding of brass particles is studied in detail in a laboratory size ball mill to determine the optimal levels of the ball to material ratio, type and amount of additives, mill speed, ball load, etc. The quality of the powder is assessed on the basis of water coverage, degree of flattening and luster by visual inspection. Preliminary results in a 35 cm diameter ball mill with 30% ball load show that a material to ball ratio of 0.067 with a 0.1% dosage of stearic acid is required for good quality powder. For determining optimal mill speed and ball size a 22 factorial design of experiment has been followed. It has been determined that to achieve best powder quality the mill must run at 70% critical speed and the ball size must not exceed 20 mm. The quality of the powder assessed through SEM study for surface morphology and particle size analysis compares very well with the industrial samples. 相似文献
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Xiaoliang Yuan Shijie Liu Guangrong Feng Yingying Liu Yongdan Li Houfang Lu Bin Liang 《Korean Journal of Chemical Engineering》2016,33(7):2134-2141
Mechanical activation is an effective method for destroying the crystalline structure. Biomass, especially its hemicellulose, can be degraded in the green solvent of liquid hot-water compressed carbon dioxide. To improve the degradation of crystalline cellulose in liquid hot-water compressed carbon dioxide, pretreatment of camphorwood sawdust by mechanical activation with a stirring ball mill was studied. Ball milling parameters and their effects on structure were determined by SEM, XRD and FT-IR. The influence of milling parameters on cellulose conversion can be ranked as follows: ball milling speed>activation time>the mass ratio of ball to biomass. The optimum milling condition was obtained at ball milling speed of 450 rpm and mass ratio of 30: 1 of ball to biomass for 2 h. In this condition, cellulose crystallinity of sawdust decreased from 60.93% to 21.40%. The cellulose conversion was 37.8%, which was nearly four times of raw material (10.2%). The glucose yield in the hydrolysate was 1.49 g·L?1, which was nearly three times of that of raw material. It showed mechanical activation can destroy the crystalline structure of cellulose to promote degradation and the damage of lignocellulosic internal structure caused by ball milling is irreversible. 相似文献