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51.
52.
High color purity red emission with single band successfully achieved in a new Er3+, Tm3+ co-doped Y2Ti2O7 system under 1550 nm excitation, value of red to green emission ratio of the samples is more than 103. Efficient up-conversion luminescence can be obtained while the 4I13/2 level of Er3+ pumped by 1500 nm directly based on the large absorption section and long luminescence lifetime, and red emission composition will greatly enhanced by co-doping with Tm3+ ions, color purity of red emission under 1550 nm excitation is much higher than that of 980 nm. The quenching concentration of Er3+ ions is up to 28 mol% in Y2Ti2O7 rely on the layer distribution of cations, which can further improve the red emission color purity. 相似文献
53.
为提高生物组织荧光成像质量以及对肿瘤的高效光热治疗,设计合成了一种新型的窄带隙共轭聚合物(BDT-TTQ),并通过纳米沉积的方式将聚合物制备成水溶性纳米粒子(BDT-TTQ NPs).该共轭聚合物纳米粒子在1000~1200 nm近红外二区范围具有较好的吸收,在1064 nm的激发光下能实现1200~1400 nm的近红外二区荧光成像. BDT-TTQ NPs纳米粒子粒径分布较窄,形貌呈规则的球形且分散均匀,具有好的生物相容性.该纳米粒子既可以在体外实现较高的近红外二区荧光成像穿透深度,又可以实现对小鼠活体血管的高清晰度的近红外二区荧光成像.此外,BDT-TTQ NPs纳米粒子在1064 nm激光下展现出优异的光热转换效率,具有较高的光毒性,对体外的肿瘤细胞以及小鼠的异质瘤具有高的光热杀伤能力. 相似文献
54.
55.
Dinghong Gu Li Huang Chunlei Shao Haojie Fang Renxi Zhang Huiqi Hou 《Frontiers of Chemistry in China》2007,2(4):436-441
The photodegradation of organic dye rhodamine B (RhB) in an aqueous solution was studied using a microwave electrodeless UV
lamp (MWUVL). The 185 nm vacuum UV (VUV) intensity of the MWUVL amounted to 12% of the total UV output, about 1.7 times as
high as that of the con ventional low-pressure mercury lamp. An acidic condition was preferred for the degradation of RhB.
Precipitate was generated during RhB degradation when the initial concentration of RhB solution was above 60 mg · L−1. For 100 mg · L−1 RhB at pH 4.0, the mass of precipitate produced was nearly half of the initial amount of RhB in the solution after irradi
ation for 75 min. The corresponding degradation ratio of RhB reached up to 99.4% and COD reduced 77.4%. The photo degradation
of RhB is mainly achieved by direct photolysis of RhB by 185 nm and OH radical oxidation.
__________
Translated from Journal of Fudan University (Natural Science), 2006, 45(6): 726–731 [译自: 复旦学报 (自然科学版)] 相似文献
56.
Dr. Ze-Lin Zhu Sheng-Fu Wang Li-Wen Fu Ji-Hua Tan Chen Cao Dr. Yi Yuan Shek-Man Yiu Dr. Ye-Xin Zhang Prof. Yun Chi Prof. Chun-Sing Lee 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(4):e202103202
Upon fusing the pyrazinyl pyrazole entity in giving pyrazolo[3,4-f]quinoxaline chelate, the corresponding Os(II) based NIR emitter exhibited “invisible” and efficient electroluminescence with a peak maximum at 811 nm. A maximum external quantum efficiency of 0.97 % and a suppressed efficiency roll-off till a current density of 300 mA cm−2 was also exhibited. 相似文献
57.
本文报道了一种全固态腔内和频608.1 nm激光器。在激光谐振腔两个分臂中,两支激光二极管分别泵浦Nd: YVO4和Nd: YAG晶体,分别选择1 342 nm波长(Nd: YVO4晶体的4F3/2-4I13/2谱线)与1 112 nm波长(Nd: YAG晶体的4F3/2-4I11/2谱线)振荡并进行腔内和频。通过优化谐振腔设计,腔内两个波长获得了较好的模式匹配。在两个分臂的交叠部分,利用LBO I类相位匹配进行和频,获得和频608.1 nm激光输出。实验表明,当Nd: YVO4与Nd: YAG晶体泵浦功率分别为600和740 mW时,获得了功率为23.8 mW、波长为608.1 nm激光输出,激光输出稳定、噪声低。利用本文提出的和频结构是获得608.1 nm激光输出较为有效的方法。 相似文献
58.
文章报道了一个二极管激光抽运的1123 nm被动调Q激光器. 激光晶体为混晶Nd:LuYAG, 饱和吸收体选为Cr4+:YAG晶体. 在连续运转情况下, 最高输出功率为2.77 W, 对应的光-光转换效率为29.53%. 调Q运转时, 在9.38 W吸收抽运功率下, 最高输出功率为0.94 W. 脉冲宽度整体在105 ns左右. 在最高吸收抽运功率下, 1123 nm激光的输出重复频率为9.40 kHz, 对应的单脉冲能量可达100 μJ, 高于目前报道的单晶Nd:YAG 1123 nm单脉冲能量, 证明其在能量存储方面较单晶Nd:YAG更具优势. 另外, 据我们所知, 这是关于混晶Nd:LuYAG 1123 nm输出的首次报道. 相似文献
59.
Nonlinear evolution equations with cosine/sine compacton solutions are reviewed, including the Rosenau-Hyman equation and generalizations of Korteweg-de Vries, Camassa-Holm, Boussinesq, Benjamin-Bona-Mahony, Klein-Gordon and other equations. Each equation is generalized to three dimensions and the conditions for its cosine solitary waves to be either a compacton or a soliton are determined. Several equations claimed in the literature to be different among them are found to be equivalent. 相似文献
60.
A highly sensitive optical humidity probe based on reflectance measurements has been developed using Nafion®-crystal violet (CV) films. This sensor can be used to calibrate relative humidity (RH) in the range 0-0.25% with a detection limit (blank signal + 3σb, where σb = the standard deviation (S.D.) of the blank signal) of 0.018% RH (∼4.37 ppm) and exhibited low hysteresis. The sensor films were fully reversible in dry nitrogen and reversal times were shown to be dependent on exposure time and % RH. The response to 1% RH was highly reproducible (S.D. = 1.67%, number of samples (n) = 5). Hydrogen chloride gas did not interfere with the response of the sensor to RH but did reduce sensor reversal times. This sensor displayed sufficient sensitivity that it could be used to detect ppm levels of moisture in process gases such as nitrogen and HCl. 相似文献