On The Realization of Active MURC Filter wth a Single Pole Amplifier
This paper presents the realization method of active MURC (multilayer uniformly distributed RC line) low pass filter with a single pole amplifier. The proposed circuit configuration consists of 2 MURC and one pole approximation of amplifier. The proposed circuit has a steeper rate of magnitude response at cut off and low sensitivities in the pass band. Experimental results of MATLAB simulations are carried
Active LPF using uniformly distributed RC line
The synthesis method of active low pass filters using uniformly distributed RC line has been published. This paper describes the Low Pass Filter (LPF) using double capacitive layers uniformly distributed RC line (DURC). This LPF circuit configuration with notch characteristics consists of DURC and a positive gain amplifier. The LPF using DURC can be used for anti-aliasing/smoothing filters for signal processors.
A bifunctional Cr/Yb/Tm:Ca3Ga2Ge3O12 phosphor with near-infrared long-lasting phosphorescence and upconversion luminescence.
Currently, upconversion nanocrystals and long-lasting phosphorescent particles have attracted extensive research interest for their possible applications as bioimaging probes. However, there are few reports concerning the achievement of both upconversion luminescence of lanthanide ions and long-lasting phosphorescence of transition metal ions in a sole host so far. Herein, we demonstrate a novel calcium gallium germanium garnet (Ca3Ga2Ge3O12) host where lanthanide ions such as Tm(3+)/Yb(3+) and transition metal ions such as Cr(3+) can be easily incorporated through substituting the Ca(2+) and Ga(3+) respectively. This Cr/Yb/Tm:Ca3Ga2Ge3O12 phosphor exhibits both broadband near-infrared long-lasting phosphorescence of Cr(3+) with an afterglow time of more than 7000 s and near-infrared to near-infrared upconversion luminescence of Tm(3+). Impressively, it is evidenced that the addition of Yb(3+)/Tm(3+) into Cr:Ca3Ga2Ge3O12 not only results in Tm(3+) upconversion luminescence but also greatly increases Cr(3+) afterglow time. Based on excitation/emission, three-dimensional thermoluminescence, and time-resolved luminescence spectra, the related long-lasting phosphorescence and upconversion luminescent mechanisms are systematically discussed as well.