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皖北任楼煤矿深层地下水稀土元素地球化学特征桂和荣,孙林华宿州学院地球科学与工程学院摘 要:为深入理解深层地下水稀土元素特征及水岩相互作用机制,对皖北任楼煤矿深部3个含水层(四含,煤系和太灰水)的稀土元素组成进行了测试,结果表明:任楼煤矿3个含水层均以轻稀土亏损,重稀土富集为特征,且均具有明显的Eu正异常以及普遍的负Ce异常,但三者在稀土分异,Eu和Ce异常程度上存在区别.其中,Ce异常主要与氧化还原程度有关,正Eu异常除与测试中BaO的干扰有关外,还原环境下Eu2+和Sr2+之间的交换,氧化状态下Eu3+的存在形态可能分别对太灰水和四含水存在影响,但煤系水中最高的正Eu异常可能主要与斜长石的溶解有关.除围岩成分,温度及酸碱度之外,稀土元素无机形态可能对地下水稀土分异程度存在重要影响.含水层之间稀土元素......
铕-丁二酸衍生物-2,2’-联吡啶三元配合物的合成和荧光性质研究刘胜利,欧阳涛,禹良才,朱金良湖南科技大学化学化工学院摘 要:分别以丁二酸(L1),2-甲基丁二酸(L2),2-亚甲基丁二酸(L3),2-巯基丁二酸(L4),2-溴基丁二酸(L5),2-羟基丁二酸(L6)为第一配体,2,2’-联吡啶(bipy)为第二配体,合成了6种稀土铕的三元配合物,通过差热分析及稀土络合滴定确定了配合物的组成为Eu2(L)3bipy.2H2O(L=丁二酸及其衍生物).通过红外光谱,荧光光谱表征了配合物的性质.对6种配合物进行荧光光谱研究,结果表明:配体取代基的变化对配合物荧光激发峰和发射峰的位置变化影响很小,但对配合物的荧光强度有较大影响,其配合物的荧光强度大小为:-SH>-Br>-H>-OH>......
Intense blue-emitting Ca2PO4Cl:Eu2+ phosphor for near-ultraviolet converting white light-emitting diodesYi-Chen Chiu1,Chun-Kuei Chang2,Yao-Tsung Yeh1,Shyue-Ming Jang11. Material and Chemical Research...">A blue phosphor Ca2PO4Cl:Eu2+(CAP:Eu2+) was synthesized by solid state reaction.The Ca2PO4Cl:Eu2+ exhibited high quantum efficiency and excellent thermal stability.The luminescent intensity......
Structure and luminescent properties of luminous polypropylene fiber based on Sr2MgSi2O7:Eu2+,Dy3+罗军,高强,张开砚,葛明桥,刘佳林Key Laboratory of Science and Technology of Eco-Textiles, Ministry of Education, Jiangnan University摘 要:The luminous polypropylene fiber based on long afterglow luminescent material Sr2MgSi2O7:Eu2+,Dy3+ was prepared by melt-spinning process......
Orange-red emitting Eu2+-activated(Sr0.883Ba0.1Lu0.0.17)3(Si0.95Al0.05)O5 phosphor: structure, photoluminescence, and application in white LEDs赵凤阳,吕雁鹏,周广洲,朴贤卿,孙卓Engineering Research Center... that the optimal content of NH4 F flux was 3 wt.% and the optimal doping concentration of Eu2+ was x=0.023 mol. The phosphors showed intense absorption in near-ultraviolet to blue region and exhibited......
Ammonium-iodide route to anhydrous EuI2: mechanism and preparation刁成鹏,余金秋,李红卫,彭鹏,吴浩,何华强,颜世宏,胡运生摘 要:Anhydrous EuI2 is an essential raw material for novel Eu2+-doped halide scintillators such as SrI2:Eu, CsBa2I5:Eu and BaBrI :Eu. An efficient and economic method to produce high purity anhydrous EuI2 is critical for future development and applications......
Synthesis and luminescence of β-SrGe(PO4)2:RE(RE=Eu2+,Eu3+,Tb3+) phosphors for UV light-emitting diodes姜雨,柳伟,曹希禹,苏革,曹立新,高荣杰Institute of Materials Science and Engineering, Ocean University of China摘 要:A new series of β-Sr Ge(PO4)2:RE(RE=Eu2+,Eu3+,Tb3+) phosphors were synthesized and characterized by using X-ray powder diffraction as well as excitation......
Luminescent and thermometric properties of dual emitting Eu2+/Sm3+ co-doped Sr4La(PO4)3O phosphor based on energy transferFuwen Liu,Degang Deng,Ming Wu,Bowen Chen,Liuyan Zhou,Shiqing XuInstitute of Optoelectronic Materials and Devices,China Jiliang University摘 要:Eu2+/Sm3+co-doped dual-emitting Sr4 La(PO4)3O phosphors were synthesized through......
蓝色长余辉发光材料Sr2MgSi2O7:Eu2+,Ln3+的合成和性质 孟媛1,曹丽莉1,周健1,翟永清1 (1.河北大学化学与环境科学学院,保定,071002) 摘要:采用凝胶-燃烧法合成了系列稀土掺杂的Sr2MgSi2O7:Eu2+0.02,Ln3+0.04(Ln=La,Ce,Nd,Sm,Gd,Tb,Dy,Ho,Er,Tm)蓝色长余辉发光材料,用X射线粉末衍射(XRD),扫描电镜(SEM),荧光分光光度计等对合成产物进行了分析和表征.结果表明:掺杂了不同稀土离子的Sr2MgSi2O7:Eu2+,Ln3+的晶体结构均为四方晶系结构;其激发,发射光谱的峰形,峰位基本无变化,激发光谱为一宽带,最大激发峰位于402nm处,次激发峰位于415nm处,与高温固相法制得的样品相比,激发峰发生了明显的红移;发射光谱也为一宽带,最大发射峰位于468nm附近,是由典型的Eu2+的4f5d-4f跃迁......
-band UV-excited SrAl2O4∶Eu, Dy phosphor derived from a mosoporous precursor was observed at λmax=515 nm due to the transitions from the 4f65d1 to the 4f7 configurations of Eu2+ ion. The main......