添加剂-磷酸对柔性石墨材料性能的影响

针对柔性石墨材料抗拉伸强度低、抗氧化性能差等问题,研究了添加剂-磷酸对其抗拉强度、抗氧化性和电阻率等性能的影响,并初步探讨了磷酸的作用机理。结果表明,添加剂-磷酸可显著提高柔性石墨材料的抗氧化性和抗拉强度,而对其它性能影响不大。随着磷酸质量分数的增加,抗拉强度先增大后减小,抗氧化性显著提高后略有降低。磷酸质量分数为9%时,抗拉强度最大,抗氧化性能最高。     

添加剂—硼酸对柔性石墨材料性能的影响

本文初步探讨了柔性石墨材料制造过程中添加硼酸的方法，并就硼酸溶液的浓度对材料性能的影响进行了比较和分析，结果表明，添加硼酸可显著提高柔性石墨材料的抗氧化能力的拉伸强度。     

添加剂－硼酸对柔性石墨材料性能的影响

本文初步探讨了柔性石墨材料创造过程中添加硼酸的方法，并就硼酸溶液的浓度对材料性能的影响进行了比较和分析．结果表明，添加硼酸可显著提高柔性石墨材料的抗氧化能力和拉抻强度．     

浸渍法提高柔性石墨抗氧化性能的研究

针对柔性石墨抗氧化性能差的问题,以磷酸、磷酸盐、硼酸盐为主要试剂配制浸渍液,通过正交试验方法确定了浸渍的最佳工艺条件.采用TG-DSC分析了漫渍液的化学组成、结构及氧化失重.结果表明,浸渍的最佳工艺条件为:蒸馏水40mL,四硼酸钠12 g,磷酸二氢钾12g,磷酸10mL,浸渍时间3h;经过浸渍处理后的柔性石墨在700℃条件下氧化1h的失重率比未处理的空白样降低90％;TG-DSC分析表明浸渍液在柔性石墨表面形成了一层抗氧化涂层,提高了柔性石墨的抗氧化性.     

短切炭纤维增强柔性石墨复合材料研究

考察了炭纤维／柔性石墨复合材料制备工艺中，炭纤维含量和长度对复合材料性能的影响。实验表明，在柔性石墨中加入适当含量和长度的炭纤维，可显著提高柔性石墨的抗拉强度和抗压强度。     

文摘

石墨电极的加压焙烧试验加压焙烧可提高石墨电极的体积密度 ,降低其电阻率 ,从而增强其抗氧化性能 ,降低其在炼钢过程中的消耗量。加压焙烧是一种提高石墨电极质量的较好方法。炭 石墨抗磨材料的抗氧化研究浸磷酸盐可提高炭 石墨抗磨材料的耐氧化性能 ,浸渍处理的后处理温度一定要高于其使用温度 ,浸渍液的组成对材料的耐氧化性能影响极大。通过调整和完善其配方 ,可进一步提高炭 石墨材料的抗氧化能力。植物纤维石膏复合板加工工艺及正交实验法研究通过正交试验对比分析 ,得出石膏基植物纤维复合板最佳材料配比 ,即当钢渣掺量 2 3 %～ 2 …     

某低品位钙基膨润土提纯、钠化及制备高效活性白土试验研究

以某低品位钙基膨润土为试验研究对象,采用湿法提纯工艺,以碳酸钠和氯化钠为钠化剂,对提纯后的膨润土进行钠化改性试验,并优化了钠化工艺条件,可将膨润土纯度从57.30%提高到89.60%。用硫酸溶液活化钠化改性膨润土以制备高效活性白土,初步研究了硫酸质量分数、活化时间、活化温度和液固质量比对活性白土性能的影响,确定了最佳工艺条件。活性白土性能测定表明,产物为脱色力强、游离酸含量低的高效活性白土。     

膨胀石墨吸附苦卤中有色物质研究

将膨胀石墨加压制成低密度板后,对海盐苦卤进行动态吸附脱色实验。确定了最佳工艺条件:温度20℃,苦卤溶液浓度(以溶液中X-计)为2mol/L,溶液pH=6,动态吸附流速为6mL/min,脱色率大于95%。膨胀石墨低密度板对海盐苦卤的饱和吸附量,比颗粒活性炭大12倍。吸附后的膨胀石墨低密度板,经加热到120℃并抽真空的方法脱附,可循环使用15次以上。     

硫酸-氢氟酸分步法提纯石墨的工艺研究

用硫酸与氢氟酸分步对原料石墨进行酸浸提纯,分别研究了硫酸和氢氟酸的反应温度、用量、反应时间对提纯效果的影响。采用外加磁场的反应器,大大缩短反应时间,提高反应效率。制取高纯石墨的最佳条件为:硫酸反应温度为80℃,6 mol/L的硫酸用量90 m L,反应时间为2 h;氢氟酸反应温度为50℃,质量分数20%的氢氟酸用量为80 m L,反应时间为2 h。经过硫酸-氢氟酸提纯之后的石墨,固定碳质量分数从79.03%可提高到98.65%,此工艺能有效缓解我国高纯石墨依靠进口的局面,应用前景广阔。     

不同改性膨润土对含磷废水的吸附试验研究

以东北建平膨润土为原料,采用KH2PO4溶液模拟含磷污水,分别对膨润土进行焙烧、酸碱药剂、钠盐及组合工艺改性研究,通过偏钼酸铵分光光度法测量改性膨润土对磷的吸附量。结果表明,几种改性后的膨润土吸附性能都得到一定改善,其中酸改性和焙烧改性膨润土对磷的吸附效果最好,最终通过正交试验得出最优组合工艺方案,当膨润土投加量为0.6 g,H2SO4质量分数为10%,改性温度为400℃时,膨润土吸附后的上清液中磷质量浓度达到最小。     

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     

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     

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     

2014 second batch of rare earth quota released

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矿用防爆轴流对旋主要通风机叶片ANSYS模态分析及应用

高效节能矿用防爆对旋主要通风机的叶片是主要通风机运行的关键部件,叶片在运行时不断受到气流的作用力,从而使叶片产生振动,当叶片振动的频率与叶片的固有频率接近时,容易产生共振从而导致叶片的断裂。一旦叶片断裂时,对主要通风机的安全运行产生致命的影响,从而导致矿山、化工等企业发生重大事故,将会产生不可估量的损失。基于有限元分析软件ANSYS,对高效节能矿用防爆轴流对旋主要通风机叶片进行模态分析及产生对应的六阶模态频率,对主要通风机叶片的运行频率、固有频率及产生的共振问题进行了原理分析,并且解决了叶片频率共振的问题,从而为主要通风机叶片结构设计提供理论依据,并对主要通风机叶片的安全运行提供保障。     

2013 NdFeB export analysis

<正>China totally exported nearly 24,000 tonsof NdFeB products during 201 3,including 18,825 tons of permanent magnet,valued USD 1.34 billion at an average price of 71.4 USD/kg;3,277 tons of NdFeB magnetic powder,valued USD 1 01 million at an average price of 30.9 USD/kg;1,334 tons of strip casting ribbon,with total export value of USD 74million at an average price of 55.3 USD/kg;and 586