聚丙烯酸铵对纳米SiO2悬浮液性能的影响

研究了聚丙烯酸铵(NH4PAA)对纳米SiO2粉体表面电动特性及其悬浮液稳定性的影响。结果表明。NH4PAA在SiO2表面吸附．提高了颗粒间的排斥势能，改善了悬浮液的稳定性。在pH为8、NH4PAA的加入量为0．9％时，纳米SiO2颗粒表面吸附达到饱和。     

SiC磨料悬浮液体系分散稳定性的影响因素研究

利用SiC表面Zeta电位的变化研究了p H值、分散剂类型及用量对SiC磨料悬浮液分散稳定性的影响。结果表明,p H值、分散剂类型及用量对SiC磨料悬浮液分散体系的分散稳定性均有显著影响。当p H=9,添加聚丙烯酸铵分散剂且添加量为0.40%时,SiC表面Zeta电位绝对值最大,此时SiC磨料悬浮液体系的分散稳定性达到最佳。     

电沉积Ni-ZrO_2复合镀层的耐蚀性能研究

在氨基磺酸盐溶液中获得了纳米Ni镀层和复合结构Ni-ZrO2镀层,两种镀层试样在4%NaCl溶液中进行耐蚀性能测试.利用X射线衍射、扫描电镜技术对镀层进行结构、形貌分析发现,Ni-ZrO2复合镀层表面颗粒更为细小,显微组织更加均匀、致密.腐蚀性能试验表明复合电镀层的耐蚀性优于纳米镍镀层的原因是因为纳米ZrO2颗粒的存在,不仅细化了基质金属的晶粒,同时提高了复合电镀层表面的化学稳定性,提高了腐蚀电位.     

水基纳米流体对钢环摩擦副减摩抗磨性能的研究

采用聚乙二醇和羧甲基纤维素钠作为分散剂,将分散剂和纳米碳化硼颗粒以一定的质量分数加入水基础液中,通过两步法制备出稳定分散的水基纳米碳化硼流体。采用单一变量法,研究了水基纳米碳化硼流体对钢环摩擦性能的影响,提出了水基纳米碳化硼流体作为传动介质的抗磨减摩机理。实验结果表明,羧甲基纤维素钠作为分散剂且质量分数为0.3%、纳米颗粒粒径为80nm且质量分数为0.8%、分散介质为去离子水时水基纳米碳化硼流体具有良好的抗磨减摩性能。当摩擦负载超过200N~250N范围之后,水基纳米碳化硼流体的抗磨减摩性能大大降低。     

低梯煤矿许用铵梯炸药的研制

本文对降低煤矿许用铵梯炸药梯恩梯(TNT)含量而设计了低梯煤矿许用铵梯炸药的配方，并从理论和实践上对其爆炸性能、安全性能、贮存期稳定性进行了分析。认为该项技术有较好的社会经济效益和推广价值。     

纳米铜粉在太阳能集热器循环工质中的分散

以阿拉伯树胶和六偏磷酸钠为分散剂,以乙二醇水溶液为分散介质,采用球磨分散法制备用作太阳能集热器循环工质的铜纳米流体.通过分光光度法和沉降法研究分散剂含量和球磨时间等因素对铜纳米流体稳定性的影响.结果表明,阿拉伯树胶和六偏磷酸钠均能有效的分散铜纳米颗粒,得到均匀、稳定的铜纳米流体.当用阿拉伯树胶作分散剂时,质量分数为0.25%、球磨时间为6h时,分散效果最佳.用六偏磷酸钠作分散剂,质量分数为0.1%、球磨时间为2h时,分散效果最佳.阿拉伯树胶对铜纳米颗粒的稳定分散作用主要是通过空间位阻机制来实现的,而六偏磷酸钠对铜纳米颗粒的稳定分散作用则主要是通过静电稳定机制来实现的.     

水基纳米流体润滑对钢环摩擦副减摩抗磨性能的影响

采用聚乙二醇和羧甲基纤维素钠作为分散剂,将分散剂和纳米碳化硼颗粒以一定的质量分数加入水基础液中,通过两步法制备出稳定分散的水基纳米碳化硼流体。采用单一变量法,研究水基纳米碳化硼流体对钢环摩擦性能的影响,提出水基纳米碳化硼流体作为传动介质的抗磨减摩机理。结果表明,羧甲基纤维素钠作为分散剂且质量分数为0.3%、纳米颗粒粒径为80 nm且质量分数为0.8%、分散介质为去离子水时水基纳米碳化硼流体具有良好的抗磨减摩性能。当摩擦负载超过200 N之后,水基纳米碳化硼流体的抗磨减摩性能大为降低。     

盱眙凹凸棒石的超声分散影响因素分析

采用超声波对凹凸棒石进行超声分散,研究了分散剂聚丙烯酸钠用量、凹凸棒石矿浆浓度、超声时间、超声波功率以及超声波工作间隙对凹凸棒石超声分散效果的影响.试验数据表明,当分散剂聚丙烯酸钠用量为0.4%、凹凸棒石矿浆浓度为9%、超声时间为13min、超声波功率为180W、超声波工作间隙为12%的分散务件下,凹凸棒石的分散效果最好.透射电子显微镜(TEM)的分析结果表明,通过超声波分散后凹凸棒石基本上以单个棒晶形式分散,说明通过超声波作用可以破坏棒晶之间的聚集力,从而获得均匀分散的凹凸棒石纳米棒晶.     

纳米SiO2表面PMMA高分子接枝改性及分散性的研究

对纳米SiO2进行硅烷偶联剂改性及PMMA高分子接枝改性,采用正交试验法优化PMMA高枝改性工艺,用FTIR,XRD,TEM及DSC-TG等手段分析了改性前后纳米SiO2的表面基团、结构、形貌及粒径,采用沉降试验法研究了改性后纳米SiO2在甲苯、丙酮有机溶剂中分散稳定性.结果表明,改性前后SiO2均呈非晶态,经PMMA高分子接枝改性后纳米SiO2为核壳结构,平均粒度小于100 nm,在甲苯、丙酮有机溶剂中具有良好的分散稳定性.     

纳米陶瓷球在某萤石粗精矿再磨中的试验研究

以某单一石英型萤石矿为研究对象,该萤石矿中CaF_2含量为34.16%、SiO_2含量为43.72%、CaCO_3含量为13.30%。通过选矿试验最终确定了1粗1扫6精的闭路试验流程。通过在精选前进行粗精矿再磨,磨矿介质采用纳米陶瓷球,得到了CaF_2含量为97.43%、回收率83.74%的萤石精矿,本试验对纳米陶瓷球在萤石粗精矿再磨中的应用具有借鉴意义。     

Market and recycling of NiMH battery

<正>Market status and future trend of NiMH battery1.Global market of small NiMH battery Global market size of small NiMH batteries declined year on year since 2011.The trend will continue to 2018,at the rate of 5%to 10%annually.Demand for small NiMH batteries will be stable gradually.Many electrical apparatuses are powered by the built-in lithium battery today,which is the main reason for the shrunk market of small NiMH batteries.But,for some products,small NiMH     

China rare earth market review

正September 1-10,2014 Affected by the National Day holiday,rare earth transaction was stagnant and the market showed a weak steady state.As there was no good news for downstream market,some products with flat demand would likely rally slightly for some time to     

Current situation and future trend of China rare earth luminescent material industry

<正>Rare earth luminescent material is one of the most important application sectors of rare earths.China enjoys the exceptional advantage to develop rare earth luminescent material for its abundant rare earth resources.After several decades'endeavor,China's rare earth luminescent material industry,headed by rare earth phosphor for lamp and LED and high efficient rare earth energy-saving light source,has been gradually developed into a scale industry.China has become a major production base of rare earth phosphor for lamps and rare earth     

China rare earth market review

正June 1~10,2014Rare earth market remained weak.Quoted price of rare earth products was similar to that in May.There was no sign of recovery in downstream market.The market of NdFeB magnetic materials and phosphor was depressed.Catalyst,polishing powder and ceramic industries remained inactive.Demand from downstream industry was soft.Consumers purchased on their needs.Suppliers had strong intention to sell.Prices of rare earth products     

2014 second batch of rare earth quota released

正~~     

Annual Report analysis of Chinese rare earth-related listed companies in 2013

<正>Chinese rare earth-related listed companies have published their 2013 annual reports.It can be understood from their reports that production and operation activities of Chinese rare earth-related companies were still heavily affected by macro economy and industrial policies.They basically followed the steps of national economy.In 2013,world economy recovered slowly but the economy     

Market opportunities and challenges for rare earth polishing powder

正1.Status of rare earth polishing powder Rare earth polishing powder with high content of cerium oxide began to replace iron oxide for glass polishing and became one of the key materials in glass polishing process since 1940.Compared with traditional iron oxide,rare earth polishing powder has many advantages,such as fast polishing rate,high polishing quality and long service life.It can achieve good surface quality and improve operation conditions.For example,in lens polishing,the polishing work that cerium     

Baotou Research Institute of Rare Earths developed a new RE alloy preparation technology

正Pyrometallurgy Laboratory of Baotou Research Institute of Rare Earths had independently developed a new preparation technology of rare earth alloy for NdFeB.The alloy can remarkably enhance the coercivity of NdFeB magnet but also evidently reduce the production cost of the magnet.The new master alloy was prepared in the kA pilot-scale electrolytic cell by the independent technology.The rare earth master alloy can be used as the raw material for NdFeB.Compared     

China rare earth market review

正November 21~30,2014Due to weak demand from downstream industries,transactions of rare earth in Chinese domestic market were inactive.It was difficult to sell any rare earth products except for dysprosium oxide and terbium oxide.Suppliers lost confidence in recent market.Demand for rare earth products was soft.Consumers continued to take a wait-and-see attitude.Rare earth export market remained slow.     

Galaxy Magnets achieved the net profit of 34.02 million yuan in the first six months of 2014

正Galaxy Magnet announced its financial results for the first half of 2014 on August 14.For the first six months ended on 30 June 2014,Galaxy Magnet achieved operation income of RMB 182.3 million,up8.40% over the same period of 2013,and the net profit attributable to the shareholders of the listed company of 34.02 million yuan,increasing 35.49% over the same period of last year.Stable performance increase was led by development of new customers and application market of magnets.