Tb3+掺杂的氟氧碲酸盐玻璃发光性能

用高温熔融法制备了Tb³⁺掺杂的氟氧碲酸盐玻璃样品,测试了不同Tb³⁺和Gd³⁺浓度玻璃样品的密度、透过光谱、以及380 nm紫外光和X射线激发的发光光谱.着重研究了玻璃中不同Tb³⁺和Gd³⁺离子含量对玻璃性能的影响规律及机理.结果表明:氟氧碲酸盐玻璃具有较大的密度,ρ大于5 g/cm³;增加Tb³⁺离子的浓度,可以有效提高样品的闪烁发光 关键词： 铽离子 氟氧碲酸盐玻璃 闪烁玻璃 发光性能     

Eu掺杂的高Gd玻璃荧光及闪烁发光性能研究

分别在空气和还原气氛下,采用高温熔融法制备了Eu 掺杂(1 wt%) 的15SiO₂-25B₂O₃-30Al₂O₃-30Gd₂O₃ 氧化物玻璃,对二者的光致发光和闪烁发光性能进行测试. 结果显示：还原气氛下制得的玻璃在395 nm 紫光和X 射线激发下,均可以得到450–550 nm 的Eu²⁺ 蓝绿发光和615 nm 的Eu³⁺ 红光;然而在不同的激发光源下,Eu²⁺ 和Eu³⁺发光强度比存在明显不同,395 nm 紫光激发下,Eu³⁺ 发光强度仅为Eu²⁺ 的0.02 倍,X 射线激发下,Eu³⁺ 发光强度变为Eu²⁺ 强度的1.37 倍. 通过声子边带谱分析,还原后玻璃中Si 形成体附近的Eu³⁺ 全部被还原为Eu²⁺,B 和Al形成体周围的Eu³⁺ 部分被还原为Eu²⁺. 进一步分析闪烁发光的机理表明：Gd 的敏化剂作用以及B 和Al 形成体周围Eu²⁺→Eu³⁺ 的能量传递都增强了还原玻璃中Eu³⁺ 的闪烁发光性能. 关键词： 高Gd玻璃 2+')" href="#">Eu²⁺ 闪烁发光 声子边带谱     

Eu^3+激活氟氧硼酸锗酸盐闪烁玻璃的发光性能

采用传统高温熔融法合成了玻璃组成为B2O3-GeO2-15GdF3-(40-x)Gd2O3-xEu2O3(0≤x≤10)的Eu^3+激活氟氧硼酸锗酸盐闪烁玻璃。在硼锗酸盐玻璃基质中,Gd2O3和GdF3稀土试剂的总含量高达55%,从而确保其密度高于6.4 g/cm^3。闪烁玻璃的光学性能通过光学透过光谱、光致发光光谱、X射线激发发射(XEL)光谱和荧光衰减曲线来表征。玻璃中Gd^3+→Eu^3+离子的能量传递通过激发光谱、发射光谱和Gd^3+-Eu^3+离子间距得到证明,同时也确定了在紫外线和X射线激发下Eu^3+激活氟氧硼酸锗酸盐闪烁玻璃的最佳浓度。Judd-Ofelt理论分析了玻璃中Eu―O键的共价性随Eu^3+掺杂浓度增加而显著增强。Eu^3+激活氟氧硼酸锗酸盐闪烁玻璃在80~470 K温度范围内荧光衰减曲线和发射光谱的温度依赖关系最终证实了其具有较好的发光稳定性。     

Tb3+掺杂高密度锗酸盐闪烁玻璃的发光性质

采用高温熔融法制备了Tb³⁺掺杂高密度锗酸盐玻璃。分别测试了该玻璃的透过光谱、密度、荧光光谱、荧光寿命及X射线激发发光光谱,揭示了该玻璃的物理化学性质和发光性质。透过光谱表明该玻璃具有良好的可见光透过率。高含量的Lu₂O₃和Gd₂O₃使得玻璃的密度高达6.4 g/cm³。该玻璃在377 nm光和X射线激发下发出强的绿光。544 nm发光的荧光寿命为1.325~1.836 ms。研究结果表明,Tb³⁺掺杂高密度锗酸盐玻璃是一种可用于慢速事件X射线探测器的候选闪烁材料。     

玻璃闪烁体的研究进展

玻璃闪烁体作为射线探测的核心材料之一在医学成像、高能物理、环境监测以及安检等领域扮演着重要的角色.根据其特点和应用背景主要分为高密度玻璃闪烁体、低密度玻璃闪烁体、微晶玻璃闪烁体.本文介绍了不同种类玻璃闪烁体的特点,重点关注了玻璃闪烁体的制备、微观结构、发光性能以及应用,并对玻璃闪烁体性能的优化以及今后的发展作出了展望.     

硅烷偶联剂改性的芪3掺杂铅-锡-氟磷酸盐玻璃发光性能的研究

采用硅烷偶联剂KBM403对SnF2粉末进行表面改性,改性粉末的IR透射谱显示KBM403已经吸附在SnF2粉末表面,这种改性除了物理吸附外还存在微弱的化学吸附。采用溶有芪3的硅烷偶联剂KBM403对SnF2粉末进行改性,经改性的SnF2粉末有利于提高有机染料芪3掺杂的分散性。将含有芪3的改性SnF2粉末掺入低熔点铅-锡-氟磷酸盐玻璃,获得了芪3掺杂的有机/无机杂化玻璃。对玻璃的吸收、透射谱和激发发射谱进行分析,表明KBM403的介入改善了芪3在玻璃中的溶解性和分散性,减少了芪3二聚物的产生,提高了玻璃的透射率和均匀性。由于KBM403的改性减少了芪3二聚物所带来的荧光猝灭,同时KBM403与染料分子的相互作用增加了染料分子的刚性,玻璃的发光强度显著提高。     

有机染料掺杂玻璃的制备及荧光性能

铅-锡-氟磷酸盐玻璃是各种激光染料及非线性染料的理想基质,本文报道了荧光素及吖啶红掺杂铅-锡-氟磷酸盐玻璃的荧光性能,并且将吖啶红掺入有机改性的钛凝胶(TiO2-Ormosil),对两者的荧光性能进行了比较。     

Eu~(3+)掺杂碲酸盐闪烁玻璃的研究

用高温熔融法制备了Eu3+掺杂的碲酸盐闪烁玻璃。测试了Eu3+不同掺杂浓度玻璃样品的密度、差热特性、吸收、发射、激发光谱及X射线激发下的闪烁光谱。研究了不同Eu3+掺杂浓度对玻璃样品的密度、光谱性能的影响规律及掺杂离子的浓度猝灭效应。研究结果表明:Eu3+掺杂碲酸盐具有较大的密度和较强的闪烁发光,随着Eu3+浓度增加,由于Eu3+间的间距减小,共振能量转移几率增大,致使发光强度增强;但当掺杂到7mol%的高浓度时,会发生浓度猝灭效应。     

氟离子掺杂钨酸铅闪烁晶体的发光特性

钨酸铅(PWO)晶体是一种综合性能非常优异的无机闪烁晶体,并且在高能物理研究领域已获得重要应用,但光输出偏低的缺点严重制约了它在非高能物理领域的应用.本文采用氟化铅作为掺杂剂,用Bridgman方法生长出了光输出比普通PWO晶体高出2—3倍的新型PWO晶体.紫外和X射线荧光光谱的测试结果表明,这种新型晶体的发光波长比纯PWO晶体红移了大约134 nm,即为553 nm,衰减时间也从几十纳秒延长到100 ns以上,且光输出随积分时间的增加而增强.此外,发射波长和光输出沿晶体生长方向存在明显的位置依赖性,初期     

Dy3+对Tb3+激活硅酸盐氟氧闪烁玻璃发光性能的影响

采用高温熔融法制备了Dy3+或Tb3+单掺和Dy3+/Tb3+共掺硅酸盐氟氧闪烁玻璃。通过对傅里叶变换红外光谱、透射光谱、光致激发和发射光谱、X射线激发发射光谱及荧光衰减曲线的分析,研究Dy3+与Tb3+之间的能量传递关系以及Dy3+对Tb3+激活硅酸盐氟氧闪烁玻璃发光性能的影响。实验结果表明：Dy3+/Tb3+共掺硅酸盐氟氧闪烁玻璃具有较高的密度和良好的可见区透过率,玻璃的网络结构是由[SiO₄]四面体和[AlO₄]四面体连接构成。在紫外光激发时,Dy3+单掺玻璃的发光源于Dy3+的4F_9/2→6H_15/2(483 nm),6H_13/2(576 nm)的跃迁发射,而Tb3+单掺玻璃的发光则源于Tb3+的5D₄→7F₆(489 nm),7F₅(544 nm),7F₄(586 nm)和7F₆(623 nm)的跃迁发射。对于Dy3+/Tb3+共掺玻璃,发射光谱则主要由Tb3+的荧光发射组成。通过对不同波长紫外光激发的发射光谱分析发现,Dy3+/Tb3+共掺闪烁玻璃中存在多种形式的能量传递。在以Dy3+的特征激发452 nm为激发波长时,Tb3+单掺玻璃的发光很弱。但随着Dy3+的引入,通过4F_9/2(Dy3+)→5D₄(Tb3+)的能量传递,Tb3+发光得到敏化增强。Dy3+/Tb3+共掺玻璃的发光强度随着Dy₂O₃含量的增多而增强,Dy₂O₃含量为1 mol%时达到最大,更高Dy₂O₃含量的样品由于Dy3+的浓度猝灭,减少了向Tb3+的能量传递,发光强度减弱。当激发波长减小到350 nm时,Dy3+和Tb3+均被激发到更高的能级6P_7/2(Dy3+)和5L₉(Tb3+),此时除了4F_9/2(Dy3+)→5D₄(Tb3+)的能量传递外,还出现了5D₄(Tb3+)→4F_9/2(Dy3+)的能量回传。Dy3+掺杂浓度较低时,Dy3+→Tb3+能量传递作用较强,Tb3+发光得到敏化增强。随着Dy₂O₃含量的增多,Tb3+→Dy3+能量传递作用增强。当Dy₂O₃含量超过0.4 mol%时,Tb3+→Dy3+能量传递强于Dy3+→Tb3+能量传递,减少了Tb3+的辐射跃迁发光,因此Dy3+/Tb3+共掺玻璃的发光强度开始减弱。由于Gd3+向Dy3+或Tb3+均可进行有效的能量传递,因此在以Gd3+的特征激发274 nm为激发光时,Dy3+/Tb3+共掺玻璃中出现了Dy3+和Tb3+对Gd3+传递能量的竞争。随着Dy₂O₃含量的增多,Tb3+所获得的能量不断减少,同时伴随着Tb3+→Dy3+能量回传和Dy3+之间的无辐射交叉弛豫作用,Dy3+/Tb3+共掺玻璃的发光强度不断减弱。对Dy3+/Tb3+共掺闪烁玻璃中Tb3+的5D₄→7F₅荧光衰减曲线分析还发现,随着Dy₂O₃含量的增多,Tb3+的荧光寿命从2.24 ms缩短到1.15 ms,曲线从单指数形式变为双指数形式,进一步证明玻璃中存在5D₄(Tb3+)→4F_9/2(Dy3+)的能量回传。X射线激发发射光谱显示,Dy3+的引入对Tb3+激活闪烁玻璃的辐射发光具有很强的负面影响,而这种负面影响不足以通过Dy3+→Tb3+能量传递来弥补,因此Dy3+/Tb3+共掺玻璃的辐射发光强度随着Dy₂O₃含量的增多而不断减弱。由此可见,在Tb3+激活硅酸盐氟氧闪烁玻璃中,不宜将Dy3+作为敏化剂,用于增强Tb3+的发光。     

Effect of gamma ray irradiation on optical properties of Nd doped phosphate glass

The effect of gamma irradiation in the dose range of 5-500 kGy on the optical absorption and luminescence spectra of Nd doped phosphate glass is reported. The spectral absorption of this glass before and after gamma irradiation was measured in the spectral range 300-900 nm at room temperature using spectrophotometer and synchrotron beamline. Drastic increase in absorption was noted below 600 nm after gamma irradiation, which was dependent on the dose of irradiation. Additional absorption (AA) spectra of irradiated sample shows generation of two absorption bands below 600 nm, which finally became one very broad band peak with increased intensity at irradiation dose of 500 kGy. AA spectra also show the presence of negative peaks at the location of absorption peaks of Nd³⁺. Photoluminescence of Nd doped phosphate glass shows two strong bands which decreases to a very low intensity with a red shift after gamma irradiation. These results indicate that irradiation produces different kinds of defects in the glass material along with conversion of valence state of Nd³⁺ to Nd²⁺. This change was found irreversible at room temperature.     

Transport properties of lead phosphate glass doped by cobalt,vanadium and chromium oxides

The electrical transport properties were investigated of a glass system of basic composition 50?mol. % Pb₃O₄–50?mol. % P₂O₅ containing CoO, Cr₂O₃ or V₂O₅ dopanys. The ac conductivity and the thermoelectric power were measured as a function of temperature. Properties such as dielectric constant, loss factor tangent and electrical conductivity are reported in the frequency range 200?Hz–100?kHz and temperature range 300–450?K. The variation in electrical conductivity with temperature was found to depend on the types of transition metal ions involved. The temperature dependence of the frequency exponent, s, was analyzed using different theoretical models. The variation of the thermoelectric power with temperature indicated the presence of more than one conduction mechanism for the investigated samples. This result was confirmed with the results of the dielectric properties at different frequencies. The introduction of cobalt ions in glass formers improves the electrical properties of non-crystalline ionic conductors.     

微柱状CsI闪烁薄膜热蒸发生长工艺

采用真空热蒸发法在石英玻璃基片上制备了具有特殊微柱状结构的碘化铯闪烁薄膜。运用扫描电子显微镜、X射线衍射仪和荧光光谱仪分别对碘化铯薄膜的形貌、结构及发光性能等进行了表征与分析。结果表明:在基片温度为260℃、沉积速率为3 nm.s-1时,所生长的碘化铯薄膜具有理想的微柱形貌、沿(110)晶面的择优取向和良好的透射性能;紫外光激发下,发射主峰为438 nm,X射线激发下,发射主峰为315nm,说明短波段发射峰需要的激发能量较高,而长波段发射峰对紫外光激发更为敏感。     

微柱状CsI闪烁薄膜热蒸发生长工艺

采用真空热蒸发法在石英玻璃基片上制备了具有特殊微柱状结构的碘化铯闪烁薄膜。运用扫描电子显微镜、X射线衍射仪和荧光光谱仪分别对碘化铯薄膜的形貌、结构及发光性能等进行了表征与分析。结果表明：在基片温度为260 ℃、沉积速率为3 nm·s-1时,所生长的碘化铯薄膜具有理想的微柱形貌、沿（110）晶面的择优取向和良好的透射性能;紫外光激发下,发射主峰为 438 nm,X射线激发下,发射主峰为315 nm,说明短波段发射峰需要的激发能量较高,而长波段发射峰对紫外光激发更为敏感。     

A new method for detecting pulse gamma ray with scattered electrons

This paper describes a newly designed gamma pulse detector of current mode that uses the scattered electron method. Tungsten is used as the scattering target, an organic thin film scintillator ST401 is used to collect the scattered electrons. The spatial distribution of the electronic energy-flux density is studied by using the MCNP code. The optimization of the target and the thickness of the scintillator are also discussed. The results indicate that the energy response is relatively flat in the range of 0.4 to 5 MeV.     

Bismuth silicate glass as host media for some selected rare-earth ions and effects of gamma irradiation

Ultraviolet, visible and infrared spectral measurements were used to investigate prepared undoped and rare-earth doped (2.5%) bismuth silicate glasses (80% Bi₂O₃–20%SiO₂) before and after being subjected to gamma irradiation (8?Mrad). The base bismuth silicate glass reveals strong extended UV–near visible absorption bands which are attributed to the presence of trace iron impurities in the raw materials together with absorption due to sharing of Bi³⁺ ions. The RE-doped samples show the same strong UV–near visible bands as the undoped glasses beside extra narrow characteristic bands mostly in the visible and near-infrared regions due to the respective studied rare-earth ions. The base undoped and all RE-doped samples except CeO₂ sample reveal quite resistance to the effect of gamma irradiation due to heavy atomic mass Bi³⁺ ions present in high content (80%) and the rare-earth ions are known to be weakly affected due to the known 5s, 5p shielding. The exceptional effect of CeO₂-doped sample is related to the ability of Ce³⁺ ions to change its oxidation state through photochemical reaction by irradiation or exchange with Fe³⁺ present as trace iron impurities. The FT infrared spectra of the prepared glasses reveal characteristic absorption bands which are related to the silicate groups together with the sharing of vibrational modes due to Bi–O groups. The IR spectra are slightly affected by gamma irradiation indicating the stability of the structural network groups consisting of SiO₄ and BiO₆ units.     

Structural investigation of glasses with doped some transition metal oxides under the influence of gamma irradiation

The ultrasonic velocity of the alkali-borosilicate with different transition metal oxides (TMO) has been studied using the pulse echo technique. The elastic moduli such as elastic constant and bulk modulus have been obtained from the experimental data. Changes in the structure with different gamma irradiation doses have been investigated by using FTIR spectroscopy and ultrasonic studies. The results show that structural changes in the BO₃ to BO₄ due to TMO and irradiation are obtained.     

Structure and properties of soda lime silicate glass doped with rare earth

Soda-lime-silicate glasses doped with different rare-earth oxides (La₂O₃, CeO₂, Nd₂O₃, Gd₂O₃ and Y₂O₃) of 1 mol% content were prepared with the traditional melting-quenching methods. In order to reveal the effects of rare-earth elements on the behavior of soda-lime-silicate glass, the structure of soda-lime-silicate glasses doped with different rare-earth oxides were determined with Fourier transform infrared spectrometer using the KBr method, and viscosity of glass melts were measured by the rotating crucible viscometer, the melting temperature of the studied glasses were derived on the basis of Arrhenius Equation, moreover the density, bending strength and molar volume were measured and calculated. The effect of rare-earth dopants on the structure of soda-lime-silicate was analyzed by a shift of peak position and variation in the full-width at half-maximum. The effect of doping rare-earth oxides into glass on the viscosity, density and bending strength was interpreted by changing in structure of soda-lime-silicate glasses doped with rare-earth oxides.     

Effect of gamma irradiation on X‐ray absorption and photoelectron spectroscopy of Nd‐doped phosphate glass

X‐ray absorption near‐edge structure (XANES) and X‐ray photoelectron spectroscopy (XPS) of Nd‐doped phosphate glasses have been studied before and after gamma irradiation. The intensity and the location of the white line peak of the L₃‐edge XANES of Nd are found to be dependent on the ratio O/Nd in the glass matrix. Gamma irradiation changes the elemental concentration of atoms in the glass matrix, which affects the peak intensity of the white line due to changes in the covalence of the chemical bonds with Nd atoms in the glass (structural changes). Sharpening of the Nd 3d_5/2 peak profile in XPS spectra indicates a deficiency of oxygen in the glasses after gamma irradiation, which is supported by energy‐dispersive X‐ray spectroscopy measurements. The ratio of non‐bridging oxygen to total oxygen in the glass after gamma radiation has been found to be correlated to the concentration of defects in the glass samples, which are responsible for its radiation resistance as well as for its coloration.     

Large phase shift of spatial soliton in lead glass by cross-phase modulation in pump-signal geometry

We investigate the co-propagation of a strong pump beam and a weak signal beam in lead glass, and find that the large phase shift of the strongly nonlocal spatial optical soliton （SNSOS） can be realized via cross-phase modulation. The theoretical study suggests a synchronous propagation of the pump SNSOS and the signal SNSOS under the required initial condition. A π-phase shift of the signal SNSOS is experimentally obtained by changing the power of the pump SNSOS by about 13 mW around the soliton critical power, which agrees qualitatively with our theoretical prediction. The ratio of the phase shift rate of the signal SNSOS to that of the pump SNSOS shows a close match to the reciprocal of the ratio between their wavelengths.