Photoluminescence of undoped and B-doped ZnO in silicate glasses

Photoluminescence of undoped and B-doped ZnO in silicate glasses was investigated by varying the concentration of ZnO (3550 mol%) and B dopant (0-10 mol%) in the glass matrices. The broad and intense near band edge emissions were observed while the visible light emission was very weak. UV luminescence in all samples was red-shifted relative to the exciton transition in bulk ZnO and enhanced by decreased ZnO concentration due to higher degree of structural integrity and the lower aggregation degree of ZnO. Donor B dopant played the double roles of filling conduction bands to broaden band gap when its concentration was lower than 5 mol%, and emerging with conduction bands to narrow the gap when B dopant exceeded this value. (c) 2007 Elsevier B.V. All rights reserved.

用光纤生物传感器检测炭疽杆菌、鼠疫杆菌及葡萄球菌肠毒素B

目的：用新研制的光纤生物传感器FOB-3检测多种病原微生物及细菌毒素.方法：利用双抗体夹心法,优化免疫反应的时间和浓度后,用FOB-3分别检测炭疽芽孢及繁殖体、鼠疫F1抗原和葡萄球菌肠毒素B.为便于结果判定,确定截断（cutoff）值,并以Ssignal与NNnoise差值的形式消除荧光信号中的噪声.结果：使用光纤生物传感器FOB-3,在20 min内可分别检测到50～1000 ng/mL的鼠疫F1抗原、0.1～100μg/mL的葡萄球菌肠毒素B、3×10^1～3×10^6 CFU/mL的炭疽杆菌繁殖体和

GeO2 : Bi, M (M = Ga, B) glasses with super-wide infrared luminescence

Broadband infrared luminescence covering the optical telecommunication wavelength region of 0, E and S bands was observed in GeO2: Bi, M (M = Ga, B) glasses prepared by conventional melting-quenching technique. The luminescence with a maximum at around 1320 nm possesses a full width at half maximum larger than 300 nm and mean fluorescent lifetime longer than 500 mus when excited by an 808 nm-laser. These glasses may have potential applications in widely tunable laser and super-broadband optical amplifier for the optical communications. (C) 2005 Elsevier B.V. All rights reserved.