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排序方式: 共有165条查询结果,搜索用时 31 毫秒
1.
《Ceramics International》2021,47(22):31470-31475
In this study, the impact of cobalt oxide (CoO) on the structure, stability, linear and nonlinear optical parameters of B2O3–Na2O–ZnO glasses was scrutinized. A series of glass system (ZnCoNaB-glasses) was successfully prepared through the melt quenching approach. Optical absorbance, reflectance, transmittance and FTIR spectroscopy were performed for all ZnCoNaB-glasses. The FTIR results showed that the BO4 units are enhanced while nonbridging oxygens are decreased with further CoO addition. Furthermore, ZnO exists as four-coordinated [ZnO4] units and these units decreased with further doping of CoO. These structural variations produce a decreasing impact in Urbach energy and nonlinear refractive index, meanwhile enhance the glass stability. Further, the metallization criterion (M) values indicate that our glass samples can be used for a new generation of nonlinear optical glasses. The preceding results can predict that the investigated ZnCoNaB-glasses will be utilized in versatile applications; especially optical switching and computing.  相似文献   
2.
Dy3+激活的几种硼酸盐在VUV-VIS范围的光谱性质   总被引:1,自引:0,他引:1  
赫泓  梁宏斌  王淑彬  苏锵  陶冶  巨新  侯雪颍 《核技术》2002,25(10):783-787
本文报道了SrAl2B2o7:Dy^3 、BaAl2B2O7:Dy^3 、SrAl3BO7:Dy^3 、La2CaB10O19:Dy^3 的紫外-真空紫外(UV-VUV)激发光谱和UV激发下的发射光谱。根据发射光谱讨论了Dy^3 离子在这几种基质中发光的黄蓝比(Y/B)。在VUV激发光谱中推测了Dy^3 的f-d跃迁及电荷迁移态(CTS)和基质吸收的位置。  相似文献   
3.
《Ceramics International》2021,47(19):27142-27150
This work presents SrO-BaO-Nb2O5-B2O3-P2O5-K2O-TiO2 glass-ceramics prepared by controlled crystallization method. The uniformly dense microstructure with fine grains can be achieved by introducing TiO2. The structural changes were confirmed by the results of SEM and TEM. The 0.5 mol% TiO2 added glass heated at 750 °C for 2 h demonstrates excellent comprehensive properties of εr= 110, BDS = 1408 kV/cm, high energy storage efficiency (η) of 92% and energy storage density of 9.65 J/cm3. The as-prepared glass-ceramic exhibits ultrahigh power density (86.21 MW/cm3), actual discharge energy density (1.00 J/cm3) and excellent temperature stability. These findings qualify this environment-friendly glass-ceramics as one potential candidate for energy storage applications, especially in high power and pulsed power system field.  相似文献   
4.
The EPR, optical absorption and photoluminescence (emission and excitation) spectra as well as decay kinetics of a series of the Ce-doped glasses with Li2B4O7, LiKB4O7, CaB4O7, and LiCaBO3 compositions have been investigated and analysed. The borate glasses were obtained from the corresponding polycrystalline compounds in the air atmosphere, using standard glass technology. The EPR signals of the isolated Ce3+ and pair Ce3+–Ce3+ centres, coupled by magnetic dipolar and exchange interactions were registered at liquid helium temperatures. The characteristic for glass host broad bands corresponding to the 4f → 5d transitions of the Ce3+centres have been observed in the optical absorption and photoluminescence (emission and excitation) spectra. The obtained luminescence decay curves can be satisfactory described by exponential function with lifetimes in the 19.8–26.1 ns range, which depend on the basic glass composition. The local structure of Ce3+ centres in the investigated glasses has been considered and discussed.  相似文献   
5.
Polarized optical functions near the fundamental absorption edge of novel Cs3Zn6B9O21 nonlinear optical crystals possessing a wide UV transparency down to 190 nm were investigated. The anisotropy of optical functions is not well studied yet which restrains the further strategy of the formation on its base of solid state compounds with desirable properties. The studies were performed using a band structure calculations as well as the experimental measurements of fundamental polarized UV absorption edge and X-ray photoelectron spectra of the studied crystals. The experimental data were used for evaluation of scissor factors of the band structure. The results of the calculations were compared with the XPS and polarized absorption optical spectra of the investigated crystals. The introduction of the scissor factor was performed in order to obtain a sufficient agreement with experiment. The observed anisotropy of absorption may be explained by the anisotropy of carrier effective masses.  相似文献   
6.
The excited state characteristics by means of the excited state absorption (ESA), optical gain and bleaching spectra have been measured for prototype glasses with Li2B4O7 (LBO) and KLiB4O7 (KLBO) compositions activated by Cr3+ ions. The work addressed to search for novel attractive media for broadband lasers and amplifiers, is a completion of detailed spectroscopic evaluation described in earlier papers. One of the examined materials (KLBO), in accordance with optimistic comments given in previous work, reveals a very broad gain spectrum in the near IR, which itself is interesting in view of very few reports on glasses showing optical gain for Cr3+ ions in the low-field local environment. The ESA/gain/bleaching spectra, registered with equipment of improved sensitivity, have been reproduced by calculations, and detailed single configuration coordinate diagram, based on experimental data, has been created for interpretation.  相似文献   
7.
Immunochromatographic assays (ICAs) are considered as a suitable diagnostic tool for the detection of mycotoxins. Mycotoxins and especially, ochratoxin A are analytes with more demanding sensitivity requirements. To enhance the sensitivity of current immunochromatographic assays for ochratoxin A (OTA), a novel sensitive ICA was developed in this study. In the assay, microspheres enclosing fluorescent europium (III) [Eu(III)] nanoparticles (EuNPs) were used as a label for OTA monoclonal antibody (OTA-mAb) conjugation. Accordingly, assay was called time-resolved fluorescent immunochromatographic assay (TRFICA). The test strip was composed of three parts: a sample pad, nitrocellulose membrane and an absorbent pad. As for detection, a proper concentration of conjugated microspheres was pipetted into the microtube and sample extract was added to it. Then the strip was inserted into the tube and the fluid flow along the strip. The TRFICA results were obtained in 8 min and read by a portable TRFICA strip reader. The established method allows quantitative determination of OTA with limit of detection as low as 1.0 μg kg−1 in the samples. For validation, spiked samples including wheat, maize, soybean and rice were respectively assayed by TRFICA and a standard high performance liquid chromatography equipped with a fluorescence detector (HPLC-FLD), and good agreement of results was obtained between two methods.  相似文献   
8.
报道三种魔芋葡甘聚糖颗粒阻溶剂的配方组成,并利用阻溶剂A进行了魔芋精粉湿法制备试验。阻溶剂A由硼酸盐──柠檬酸盐──亚硫酸盐组成,其主体成分为硼酸盐,在鲜魔芋块茎磨碎时加入磨浆机中,能有效地防止魔芋葡甘聚糖颗粒的溶胀粘连。  相似文献   
9.
水溶性含氮硼酸酯摩擦学性能研究   总被引:7,自引:2,他引:7  
利用四球机和环块试验机考察了两种水溶性含氮硼酸酯的摩擦学性能,并用X-射线光电子能谱仪(XPS)对摩擦表面进行了分析,摩擦学试验表明:含氮硼酸酯在水中具有良好的减摩抗磨性能和承载能力,表面分析证实含氮硼酸酯在摩擦过程中发生了摩擦化学反应,生成了含硼酸,三氧化二硼,有机氮等的复合膜,有效地提高了水基液的抗磨减摩性能和承载能力。  相似文献   
10.
模拟含硼废液喷雾干燥试验   总被引:1,自引:0,他引:1  
安鸿翔  周连泉  范智文  孙琦  林小龙 《辐射防护》2007,27(5):297-301,320
研究了三种喷雾干燥方式处理模拟含硼废液试验的性能和影响因素.三种喷雾干燥方式为:旋转式雾化并流喷雾干燥、气流式雾化并流喷雾干燥和气流式雾化混合流动喷雾干燥.对于硼浓度21 000 ppm(10-6)的模拟含硼废液,在供料温度为62~64 ℃,干燥塔进出口温度分别为210~220 ℃和110~120 ℃,压空流量为8.0 m3/h,雾化器转速为73.0 m/s的条件下,三种喷雾干燥方式均得到了流动性良好的粉体,粉体中占总质量95%的粉体粒径在0.356~0.061 mm之间.三种喷雾干燥方式处理模拟含硼废液的减容系数在0.22~0.27之间,气流式雾化并流喷雾干燥方式、气流式雾化混合流动喷雾干燥方式和旋转式雾化并流喷雾干燥方式的废液处理能力依次增大,所得粉体的含水率依次增大.  相似文献   
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