长余辉发光材料研究进展

第一次观察到Sm~(3 )、Tm~(3 )、Yb~(3 )的红色和橙红色长余辉发光;首次在含镉的氧化物中观察到红、绿、蓝等多种颜色的新型长余辉发光,特别第一次观察到非稀土离子如Pb~(2 )、Bi~(3 )、Sn~(2 )、Sb~(3 )的长余辉发光现象;首先发现在一种基质中由一种稀土离子(Dy~(3 ))激活产生的发白色光的长余辉发光材料;第一次观察到Er~(3 )、Ho~(3 )的绿色长余辉发光;在掺Tm~(3 )的材料中发现迄今为止未见国内外报道的800nm最长波长的长余辉发射;在掺Tm~(3 )的材料中初步观察到既有上转换发光又具有长余辉发射的新的发光现象;开展了长余辉发光材料的纳米组装,以及开拓这类材料在环境和生物医学领域的应用研究。研究的能产生长余辉发光的激活离子和基质化合物已有较大扩展,并发现了一些变化规律及用现有模型和规则难以说明和解释的新的现象。迄今,文献报道的具有长余辉发光的基质和离子主要是铝酸盐、硅酸盐、硫氧化钇等基质和Eu~(2 )、Eu~(3 )、Ce~(3 )、Tb~(3 )、Pr~(3 )、Mn~(2 )等离子,拓展到锗酸盐、钨酸盐、镓酸盐、石榴石、含镉的氧化物以及稀土硫氧化物等...     

农业院校科研基地建设对产学研的促进作用初探

在中国,农业院校肩负着推进农业现代化的重任,在具体实施的过程中主要通过"农科教"和"产学研"两种方式展开。对于农业院校而言,其最大优势在于具备辽阔的实验基地,而基地建设无论在"农科教"还是"产学研"模式中都具有举足轻重的作用。文章针对农业院校在产学研合作模式下,强调科研基地建设的重要性及功能的开发,提出了在产学研一体化下基地的建设与分区规划,以及相应的管理与实施措施。     

关于《材料化学专业英语》课堂教学方法探索

《材料化学专业英语》是针对材料化学专业学生开设的一门专业课程,具有很强的专业性、应用性。从目标、施教方案、反馈效果等方面进行系统策划,围绕材料化学专业英语课程教学,大力推进教学方法改革,开展切实可行的实践教学。结合教学实践,探讨如何设计教学过程,改进教学方法,提高教学效率。     

石墨烯薄膜制备与表征综合性实验教学设计

坚持为"基础化学实验"课程补充新内容,甚至追踪科学前沿是有必要的。结合"碳材料研究"科研课题,设计适合本科新生实验操作的"石墨烯薄膜制备与表征"实验方案。该方案为综合性实验,包含氧化石墨烯制备与还原,材料二维形貌控制与成形以及相关性质的表征等环节,整个实验教学系统完整地模拟科学研究过程,实验条件简单,设备易普及,实验现象重现性好,实验结果可靠。该实验教学设计有助于学生实验技能的培养,科研思维与创新意识的建立,从而实现提高学科教育与教学质量的目的。     

Synthesis and luminescence properties of SrAleO4：Eue＋,Dy3＋ hollow microspheres via a solvothermal co-precipitation method

SrAl2O4:Eu2+,Dy3+ hollow microspheres were successfully prepared through a facile and mild solvothermal co-precipitation combining with a postcalcining process.The structure and particle morphology were investigated by X-ray diffraction(XRD),scanning and transmission electron microscopy(SEM and TEM)pictures,respectively.The mechanism for the formation of spherical SrAl2O4:Eu2+,Dy3+ phosphor was preliminary presented.After being irradiated with ultraviolet(UV)light,the spherical phosphor emitted long-lasting green phosphorescence.Both the photoluminescence(PL)spectra and luminance decay,compared with that of commercial bulky powders,revealed that the phosphors had efficient luminescent and long lasting properties.It was considered that the SrAl2O4:Eu2+,Dy3+ hollow microspheres had promising long-lasting phosphorescence with potential scale-dependent applications in photonic devices.     

Long-Lasting Properties of Rare Earth-Doped Y2O2S Phosphors

The aim of this presentation is to report a new result of afterglow materials. The Y2O2S:Ln^3 (Ln = Sm, Tm)phosphors show bright reddish orange and orange-yellow colors when excited by UV or visible light. The main spectroscopic characterizations of Sm^3 and Tm^3 in yttrium oxysulfide and their long-lasting phosphorescence were measured and discussed in this presentation. Their long-lasting phosphorescence can be seen by the naked eyes clearly for about one hour in the dark room after the irradiation light sources were removed. XRD and photoluminescence (PL) spectra as well as the luminance decay were used to characterize these long-lasting phosphorescence phosphors. The results of XRD indicate that the products synthesized through the flux fusion method under 1050℃ for 6 h have a good crystallization without any detectable amount of impurity phase. Both the PL spectra and luminance decay results reveal that these phosphors have efficient luminescent and good long-lasting properties. We believe that the experimental data gathered in our present work will be useful in finding some new long-lasting phosphors with different colors.     

Luminescence Properties of Rare Earth Ions in Cadmium Metasilicate

The luminescence properties of CdSiO3:RE^3 phosphors doped with various rare earth ions are reported. The series of rare earth ions doped CdSiO3 phosphors are prepared by the conventional high-temperature solid-state method, and characterized by XRD and photoluminescence (PL) spectra. The results of XRD measurement indicate that the products fired under 1050 ~C for 3 h have a good crystallization without any detectable amount of impure phase. The PL spectra measurement results show that CdSiO3 is a novel self-activated luminescent matrix. When rare earth ions such as Y^3 ,La^3 , Gd^3 , Lu^3 , Ce^3 , Nd^3 , Ho^3 , Er^3 , Tm^3 and Yb^3 are introduced into the CdSiO3 host, one broadband centered at about 420 nm resulted from traps can be observed. In the case of other earth ions which show emissions at the visible spectrum region, such as Pr^3 , Sm^3 , Eu^3 , Tb^3 and Dy3 , the mixture of their characteristic line emissions with the ～420 nm strong broadband luminescence results in various emitting colors. As a consequence, different emitting colors can be attairied via introducing certain appropriate active ions into the CdSiO3 matrix. In additional, this kind of phosphors shows good long-lasting properties when excited by UV light. All the results show that CdSiO3 is a potential luminance matrix.