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1.
样品溶液经CL-5209萃淋树脂在2mol/L硝酸介质中分离铀后,用催化极谱法测定铌。铌在0.8%H2SO4-0.05mol/L酒石酸-2%KSCN-0.08%抗坏血酸-0.0004%聚乙烯醇底液中,于-1.3V处呈现络合催化氢波(vs.SCE)可用二次导数测定。铌峰电流与浓度(0.005~0.03μg/mL)有线性关系。称样0.1g时,铌的测定下限为0.5μg/gU、6次测定相对标准偏差<15%,加入回收率为91%~119%。 相似文献
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二氧化铀中微量铍和钍的测定 总被引:1,自引:0,他引:1
在三乙醇胺体系中,利用桑色素荧光光度法测定微量铍,当激发波长为400um时,铍-桑色素络合物的最大荧光波长为525um,铍的标准曲线范围为0.05~1.0μg/10mL。在盐酸介质中,利用偶氮胂-TBC分光光度法测定微量钍,钍的测定波长为635um,标准曲线的范围为0.2~5.0μg/25mL。利用CL-5209萃淋树脂进行了大量铀中微量铍和钍的分离。在1mol/LHNO3中,由于铀和钍的吸附,微量铍被定量分离,在1mol/LHCl+1mol/LNaCl介质中,微量钍可被定量淋洗。二氧化铀样品中铍和钍测定结果的相对标偏优于5%。 相似文献
3.
催化极谱法测定痕量钒 总被引:1,自引:0,他引:1
在0.001%铍试剂Ⅱ-1.2%溴酸钾-0.4%氟化铵-1.2×10^-2mol/L醋酸-醋酸钠介质中,钒在峰电位为-0.65V产生一个良好的导数极谱波,当钒浓度在7.8×10^-8-3.1×10^-6mol/L范围,峰电流与浓度成正比,大量铁及其他杂质不干扰,可直接测定低合金钢中痕量钒,方法简单,快速,准确。 相似文献
4.
样品溶液经CL-5209#淋树脂在2mol/L硝酸介质中分离铀后,用催化极谱法测钛。在含乙酸一乙酸铰缓冲液(pH5.5)的0.4%EDTA-0.002%铜铁试剂一0.005mol/L溴酸钠底液中,于一0.65V(vs.SCE)有一钛催化波,进行二次导数测定。钛峰高与浓度在0.005-0.05μg/mL有线性关系。称样0.1g钛的测定下限为0.5μg/g。相对标准偏差优于6%,加入回收率为94%一106%。 相似文献
5.
本法采用TBP萃取树脂,利用革取色谱分离技术,使铀与待测杂质元素在3mol/LHNO3介质中得到定量分离。用975型ICP直读光谱仪同时测定八氧化三铀系列标准物质中Ca、Cd、Cr、Cu、Fe、Mg、Mn、Mo、Ni、Ph和Sn11种杂质。测定下限为0.02—1.6μg·g-1,相对标准偏差<10%。分析结果均落在标准值的置信区间内 相似文献
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阐述了用γ-Fe2O3.H2O及FeO(OH)处理煤系硫铁矿的方法及最佳条件,试验表明明在γ-Fe2O3.H2O的量为60g/L,溶液酸度在pH0.5~1.0范围内,通过0.3L/min的空气并加热至沸的情况下,对10g/L硫铁矿反应16h,硫铁矿硫脱除率可达90%以上,比单纯用FeCl3氧化硫铁矿快3h以上。 相似文献
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《Analyst》1998年第123卷第1期刊登了YaseminT.等人用三辛胺(TOA)浸渍的聚氨酯泡沫塑料从水溶液中回收铀的文章。作者对萃取条件和解脱进行了详细研究。最佳萃取条件为:水溶液中铀浓度为25×10-6;萃取溶液酸度为pH=2;萃取溶液体积与TOA浸渍的聚氨酯泡沫塑料的质量比为500(mL/g);TOA-环己烷溶液中TOA浓度为10%(V/V);萃取时间为1h;萃取温度为23℃。在上述最佳条件下,铀的回收率为90.0±3.0%。用(NH4)2SO4、Na2CO3、NH4Cl-HCI… 相似文献
9.
在1mol/L硝酸介质中,铀被CL—5209萃淋树脂定量吸附,并与铅、镉等元素分离。收集流出液,加热蒸干后,在酸性(pH=2)底液中,铅和镉与碘离子生成络合物吸附于滴汞上,可进行阴极化二次导数极谱法测定。铅、镉的峰电位分别为-0.62V、-0.80V(相对饱和甘汞电极)。铅、镉浓度在0.01—1.0μg/mL是线性关系,对于痕量镉(小于0.1ppm)的测定可在测定铅的波高之后,再加入一滴四丁基碘化铵乙醇溶液,镉的波高增加3倍,并有线性关系。方法精密度≤±10%,回收率为90%-110%。 相似文献
10.
采用CL—5208萃淋树脂分离铀后,用二次导数极谱法测定铀氧化物中的镉.方法的相对标准偏差优于10%,回收率95%-111%。称样0.200g时,测定下限可达0.05μg/g。 相似文献
11.
<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 相似文献
12.
《中国稀土信息(英文版)》2014,(6)
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 相似文献
13.
YANG Li 《中国稀土信息(英文版)》2014,(6)
<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 相似文献
14.
Gao Wei 《中国稀土信息(英文版)》2014,(11)
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 相似文献
15.
《中国稀土信息(英文版)》2014,(8)
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 相似文献
16.
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。 相似文献
17.
Chen Zhanheng 《中国稀土信息(英文版)》2014,(5)
<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 相似文献
18.
Bai Wenping 《中国稀土信息(英文版)》2014,(12)
<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 相似文献
19.
《中国稀土信息(英文版)》2014,(9)
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 相似文献
20.
研究工作面瓦斯涌出规律对工作面瓦斯治理有重要意义。为了得到唐口煤矿深部3号煤层复杂开采条件下工作面回采时期瓦斯涌出时空演化规律,选取6304工作面作为对象,采用实测方法研究6304工作面瓦斯涌出规律。结果表明:6304工作面瓦斯涌出量为6.534 m3/min,其中煤壁占34.27%,落煤占29.62%,采空区占36.11%;沿工作面倾向由低到高,瓦斯浓度整体为上升趋势,其中1—76号架工作面瓦斯浓度小于0.20%,76—102号架瓦斯浓度上升明显,最大为0.387%;上隅角的后部采空区是工作面的瓦斯主要涌出源,上隅角1号测点瓦斯浓度0.78%,上隅角周边3号、5号、7号、8号、9号测点瓦斯浓度平均为0.643%;周期来压时,上隅角瓦斯相对平时较高。研究为针对性的瓦斯分源监控与灾害防治提供基础。 相似文献