陶瓷厚膜电致发光器件的电致发光特性研究

研制了以四元系组分ＰＭＮ－ＰＴ－ＰＦＮ－ＰＣＷ陶瓷厚膜为绝缘层的无Ｙ２Ｏ３介质层和有Ｙ２Ｏ３介质层两种结构的电致发光器件,并对陶瓷厚膜的制备民厚膜厚度等对陶瓷厚膜电致发光器件电致发光特性的影响进行了深入的研究。     

970nmLD激发Tm^3＋,Yb^3＋掺杂的MFT玻璃材料上转换发光的研究

设计并制备了一种Ｔｍ＾３＋、Ｙｂ＾３＋共掺杂的多氟化物调整碲酸盐（ＭＦＴ）玻璃材料,其组份为５０ＴｅＯ２－１４．ＰｂＦ２－１０ＡｌＦ３－１０ＢａＦ２－１０ＮａＦ－０．１Ｔｍ２Ｏ３－５Ｙｂ２Ｏ３。测量了该玻璃系统的Ｒａｍａｎ散射光谱,在９７０ｎｍＬＤ激发下裸眼可以观察到很强的蓝色我,光谱测量证实这个蓝色发射（４７６ｎｍ）来源于＾１Ｇ４→＾３Ｈ６的跃迁,同时,还有两个较弱的红色发射源于＾１Ｇ４→＾３Ｈ     

安培力的微观解释

安培力的微观解释邓小玖（合肥工业大学合肥２３０００９）１．前言目前《电磁学》的有关书籍较普遍地认为［１］，［２］：导线所受的安培力就是作用在各自由电子上洛仑兹力的宏观表现。这就会留下一个疑问：磁场中的载流导线在稳流条件下，导线中的自由电子并没有相对导...     

ZnS∶Tb薄膜电致发光的量子效率及过热电子分布

采用高频溅射的方法制备了高亮度的ＺｎＳ∶Ｔｂ薄膜电致发光器件．测量了发射强度比Ｉ（５Ｄ３－７Ｆ６）／Ｉ（５Ｄ４－７Ｆ４）随激发电压的变化关系、弛豫时间及发光的量子效率，计算了碰撞截面，分析ＺｎＳ∶Ｔｂ的过热电子的分布，并与ＺｎＳ∶Ｍｎ进行了比较．指出了ＺｎＳ∶Ｔｂ效率与ＺｎＳ∶Ｍｎ效率差异的可能原因．     

能斯脱热定理与热力学第三定律

 一、能斯脱热定理的发现本世纪初低温技术的进一步发展,同时化学热力学理论也达到了一定的发展水平,这样历史为热力学第三定律的发现准备了成熟的条件。1906年能斯脱(Nernst)系统地研究了低温下的化学反应后,得出结论说,在趋近于绝对零度时,化学亲合势A和反应热Q相等。     

Tm3+在亚碲酸盐玻璃中升频发光的研究及其光谱性质的J-O计算

报道了一种新组份亚碲酸盐玻璃作为掺稀土基质在提高升频发光效率方面的优良特性.在970mmLD泵浦下这种Tm³⁺掺杂的亚碲酸玻璃明显的蓝色及红色升频发光,通过测量其吸收光谱,用J-O理论计算了这种玻璃基质中Tm³⁺离子各发光能级的自发辐射几率、跃迁振子强度、分支比及寿命等光谱参量.并计算了481mm和650mm两种发光的发射截面.     

生物膜电极反应器降解对氨基二甲基苯胺的研究

采用生物膜电极法降解对氨基二甲基苯胺, 并与生物法降解和电化学降解的效果进行了比较.     

STATISTICAL STUDIES ON THE RELATIONSHIP BETWEEN WIDTHS AND RETENTION TIMES OF GAS CHROMATOGRAPHIC PEAKS

The k' (capacity ratio)and w_(1/2) (width at half peak height) values of chromatographic peaks were measured for the members of three homologous series, i.e. n-alkanes, n-alkyl alcohols and n-alkyl benzencs on three packed columns with OV 22,5, EGS or PEG 4000 as liquid phase respectively under suitable chromatographic conditions. It was found that the k'-w_(1/2) points of any homologous series on any column did not fall into a straight line, while they were best fitted by a curve.When the method of linear regression was applied to the k'-w_(1/2) data in order to make a comparison with the results of other chromatographers, it was proven that the linear regression lines obtained on the same column for samples of different homologous series always differed significantly.Whether β, a column parameter proposed by Lu, the author who advanced the theory of multi-component chromatography, may hold constant was also experimentally tested, and it was concluded that the constancy of β found little experimental     

不同掺杂浓度Tm3+：LiLuF4单晶的1800 nm荧光发射

采用坩埚下降法生长了Tm³⁺掺杂浓度为0.45%,0.90%,1.63%与3.25%（摩尔分数,x）的LiLuF₄单晶.测试了样品的电感耦合等离子体原子发射光谱（ICP-AES）、X射线衍射（XRD）谱、吸收光谱（1400-2000 nm）,并且分析比较了808 nm半导体激光器（LD）激发下荧光光谱. 结果表明：当Tm³⁺的浓度从0.45%变化到3.25%时,1800 nm处的荧光强度呈现了先增后减的趋势,当掺杂浓度约为0.90%时达到最大值,而位于1470 nm处的荧光强度则呈现了相反的趋势. Tm³⁺：³F₄能级的荧光衰减寿命随着掺杂浓度的增加不断减小. 1800 nm处的这种荧光强度变化归结于Tm³⁺离子间的交叉驰豫效应（³H₆,³H₄→³F₄,³F₄）和自身的浓度猝灭效应. 同时计算得到了浓度为0.90%的样品在1890 nm处的最大发射截面为0.392×10^-20 cm². 并且根据Judd-Ofelt 理论所得寿命和测定的荧光寿命计算得到了³F₄→³H₆的最大量子效率约为120%.     

Optimum fluorescence emission around 1.8 μm for LiYF4 single crystals of various Tm3＋-doping concentrations

In this paper, optical spectra of LiYF4 single crystals doped with Tm3＋ ions of various concentrations are reported. The emission intensity at 1.8 ktm first increases with increasing Tm3＋ concentration, and reaches a maximum value when the concentration of Tm3＋ is about 1.28 mol%, then it decreases rapidly as the concentration of Tm3＋ further increases to 3.49 mol%. The emission lifetime at 1.8 p.m also shows a similar tendency to the emission intensity. The maximum lifetime of 1.8 μm is measured to be 17.68 ms for the sample doped with Tm3＋ of 1.28 mol%. The emission cross section of 3F4 level is calculated. The maximum reaches 3.76 × 10 -21 cm2 at 1909 nm. The cross relaxation （3H6, 3H4 →3 F4, 3F4） between Tm3＋ ions and the concentration quenching effect are mainly attributed to the change of emission with Tm3＋ concentration. The largest quantum efficiency between Tm3＋ ions is estimated to be ,-147% from the measured lifetime and calculated radiative lifetime. All the results suggest that the Tm3＋/LiYF4 single crystal may have potential applications in 2 μm mid-infrared lasers.