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无硫高抗氧化膨胀石墨及其制品的生产 总被引:1,自引:1,他引:0
本文介绍了无硫高抗氧化膨胀石墨及其制品的生产工艺。石墨经过稀硝酸和高锰酸钾酸化,水洗时加入HW还原剂以减少锰、钾杂质会量,再经一种新型抗氧化剂处理,烘干、膨化,得到膨化石墨,压制成型后即得其制品。制品抗氧化能力和抗拉强度大幅度提高。酸化过程中,稀硝酸可回收利用多次。 相似文献
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以硝酸、乙酸为主插层剂,KMnO_4为氧化剂,磷酸、硝酸为辅助插层剂,采用分步插层法制备膨胀石墨。通过单因素变量法,在研究主插层剂最佳插层条件的基础上,考察辅助插层剂(磷酸和硝酸)对制备膨胀石墨的影响。结果表明,在最佳制备条件下,膨胀石墨的膨胀体积约为116 mL/g;当加入辅助插层剂磷酸时,膨胀体积约为180 mL/g;继续加入辅助插层剂硝酸时,膨胀体积最大约为172 mL/g。说明加入辅助插层剂磷酸后石墨的膨胀体积明显增大,加入辅助插层剂硝酸后石墨的膨胀体积略有下降。用SEM进行表征,结果与单因素试验结果一致,说明辅助插层剂磷酸对石墨膨胀体积有明显影响。 相似文献
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以细鳞片石墨及硫酸、硝酸、磷酸及高锰酸钾的适当配比.采用化学法经氧化酸化插层、水洗、干燥、高温膨胀过程制备得到膨胀石墨,通过对比实验获得了膨胀倍数为230ml/g的低硫细鳞片膨胀石墨.其最佳工艺条件为:硫酸:硝酸:磷酸=1:1:3,KMnO4用量为石墨质量的15%,反应温度25℃、反应时间为100min、膨胀温度1000℃. 相似文献
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以天然鳞片石墨为原料,硝酸、磷酸为插层剂,高锰酸钾为氧化剂,采用化学法经氧化酸化插层制备无硫可膨胀石墨,利用正交试验方法确定最佳工艺条件,并对产品进行XRD、SEM测试。结果表明:在反应温度75℃,反应时间30min,石墨(g)︰KMnO4(g)︰HNO3(ml)︰H3PO4(ml)=10︰1.0︰22︰32条件下,可以制备出膨胀体积达150ml/g的无硫膨胀石墨。相关影响因素的大小依次为:高锰酸钾、反应温度、反应时间、硝酸用量、磷酸用量。XRD测试表明膨胀石墨晶体未受破坏,SEM可见蠕虫状膨胀石墨结构。 相似文献
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陈小兰 《广东有色金属学报》2003,13(1):73-75
先用硝酸 氢氟酸溶解磷酸锆银钠样品,再加氨水(1 1)使其转换成氨性溶液,然后用原子吸收分光光度法测定磷酸锆银钠中的银.本法测定结果与火试金法测定结果一致,相对标准偏差小于0.37%,回收率大于95%. 相似文献
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以非高纯混合目天然鳞片石墨、硝酸、高锰酸钾、双氧水为原料,采用化学法经氧化酸化插层、水洗、干燥过程,制备无硫低灰分可膨胀石墨。用磷酸二氢钾饱和溶液、硼酸饱和溶液、磷酸及这3种溶液的混合液作为抗氧化剂进行二次浸渍插层,可制备得到最大膨胀体积为280mL/g的无硫高抗氧化性可膨胀石墨。研究了加入抗氧化剂后膨胀体积变化情况及氧化温度、氧化时间与抗氧化性的关系。结果表明,加入抗氧化剂后的可膨胀石墨具有更高的抗氧化性和膨胀倍数,其中磷酸与磷酸二氢钾混合溶液、磷酸与硼酸混合溶液、磷酸作为抗氧化剂时,膨胀石墨的抗氧化能力较强。 相似文献
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Ye Peipei 《中国稀土信息(英文版)》2014,(7)
<正>Extracted from Securities Guide 1.Popularity of new energy vehicles—an irresistible market trend1.1 Progress of new energy vehicles Chinese Premier Li Keqiang said recently on a visit to Xi'an BYD Autos that new energy vehicles,especially new energy bus,can lessen environment and noise pollution.He encouraged the use of new 相似文献
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《中国稀土信息(英文版)》2014,(11)
正November 1~10,2014Chinese rare earth market was still inactive.Demand for rare earth products was weak.Consumers took a wait-and-see attitude for lower price.As it was an off season for rare earth products,it was expected that prices of rare earth could continue turbulence at the bottom in short terms.Due to a sharp drop,demand for rare earth from downstream recovered.Affected by new energy vehicles,wind powder and energy-efficient appliances,production of rare earth permanent 相似文献
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《中国稀土信息(英文版)》2014,(8)
正August 1~10,2014 There was some good news in rare earth industry recently.Restructuring plans of rare earth groups led by Baotou IronSteel Group and Xiamen Tungsten Group respectively have been approved by MIIT.And rare earth storage policy,which had been expected for a very long time,has been launched officially.Pushed by the good news,rare earth price started to rebound since August 5.Price of didymium oxide and dysprosium oxide rose about 1% to 2%,averagely.About 10% of 相似文献
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《中国稀土信息(英文版)》2014,(7)
正July 1~10,2014Due to weak demand from downstream industry and slow transactions,rare earth market remained weak and price of rare earth products continued to decline.There was no sign of recovery in downstream market.The market of NdFeB magnetic materials and phosphor was depressed.Catalyst, 相似文献
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针对煤矿开采深度不断向深部延伸,掘进巷道受深部高应力的影响越来越大,巷道围岩整体稳定性差,矿山压力显现越剧烈现象,一般锚网喷加锚索支护无法从根本上控制巷道的变形。总结了平煤股份十三矿-685 m进风大巷注浆加固技术,依据对巷道掘进之后变形监测数据的采集,对巷道变形机理进行分析研究,并对注浆时段进行了合理选择,在对巷道的注浆工艺进行了充分论证的基础上,对巷道进行了注浆。注浆后效果表明:巷道滞后注浆时间段的选择非常重要,巷道在恰当的时间内进行注浆加固施工,能有效控制巷道的变形,巷道注浆后变形量明显减小,岩体的稳定性明显增强,减少了巷道日常维修工作,降低了矿井的生产成本,保障了矿井的安全生产。 相似文献
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《中国稀土信息(英文版)》2014,(9)
正China Minmetals Rare Earth Construction of Jianghua Separation Plant is set to complete at the yearend Civil works of Jianghua Separation Plant have been finished and the company is installing and debugging equipments now.It is estimated that construction of Jianghua Separation Plant will be 相似文献
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《中国稀土信息(英文版)》2014,(11)
正Total transactions of rare earth in Rare Earth Ex-change Center of Hunan South Rare and Precious Metal Exchange neared 40 billion yuan from January to October From the opening in January of this year to the end of October,the total transaction of rare earth products in Rare Earth Exchange Center of Hunan South Rare and Precious Metal Exchange neared40 billion yuan.There are 16 varieties including dysprosium oxide and terbium oxide traded on the exchange center,one of the largest trading platforms for rare earth oxides in China. 相似文献
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A hypothesis that associates optimal conditions of mineral flotation with a zero charge of their surface is put forward. This
hypothesis serves as a basis for a methodology to obtain and verify quantitative physical-chemical models for a minimal necessary
concentration of a collector during flotation of sulfide-free minerals. These models may be of use for upgrading engineering
processes of flotation and as a job for the concentration plant automation systems.
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Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 2, pp. 89–99, March–April, 2006. 相似文献
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随着地下采煤活动不断加大,越来越多的输电杆塔不可避免地被建设在煤矿沉陷区。目前,现有手段采用靠人力去进行定期检查一定会浪费大量的人力和物力,因而需开展对位于煤矿沉陷区的杆塔进行实时在线检测。基于NB-IoT和LoRa提出了一种新的算法——低功耗广域网(LPWAN)技术,提出了一种新型的输电杆塔倾斜监测系统,其中包含1个主节点和多个子节点,以适应地域广和远距离的需求信息监控。该系统通过LoRa多节点网络的数据传输,将杆塔的倾斜参数通过NB-IoT上传至在线实时监控系统。管理人员可以从后台得出监测数据并分析结果,及时对处于煤矿沉陷区的有故障的输电杆塔进行针对性的维护。 相似文献
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讨论了在煤矿提升机二级制动的基础上 ,对制动力矩进行补偿 ,保证提升机紧急制动时的减速度维持在《煤矿安全规程》规定的范围内。 相似文献