Preparation and characterisation of irradiated waste eggshells as oil adsorbent

Adsorption method had been developed by using natural organic adsorbent for the removal of oil because of its ability to bind the oil molecules into the surface of adsorbent. In this study, chicken eggshells waste was used and it undergoes irradiation process with four different amount of dose which was 0.5 kGy, 1.0 kGy, 1.5 kGy, and 2.0 kGy by using Gamma Cell Irradiator. Three equipment had been used for the characterization process which were the Scanning Electron Microscope (SEM), Energy Dispersive X-ray spectroscopy (EDX), and Fourier-Transform Infrared Spectroscopy (FTIR). The adsorption experiment was conducted to calculate the sorption efficiency by using different mass of samples. The result showed that irradiated chicken eggshells powder with 2.0 kGy amount of radiation dose has a best performance as oil adsorbent

BiCMOS variable gain transimpedance amplifier for automotive applications

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Large-Area, Low-Noise, High Speed, Photodiode-Based Fluorescence Detectors with Fast Overdrive Recovery

Two large-area, low noise, high speed fluorescence detectors have been built. One detector consists of a photodiode with an area of 28 mm x 28 mm and a low noise transimpedance amplifier. This detector has a input light-equivalent spectral noise density of less than 3 pW/Hz^1/2, can recover from a large scattered light pulse within 10 us, and has a bandwidth of at least 900 kHz. The second detector consists of a 16 mm diameter avalanche photodiode and a low-noise transimpedance amplifier. This detector has an input light-equivalent spectral noise density of 0.08 pW/Hz^1/2, also can recover from a large scattered light pulse within 10 us, and has a bandwidth of 1 MHz.Comment: Submitted to Review of Scientific Instrument

Exact design solutions for photodiode transimpedance amplifiers based on FET input OP-AMPs

We calculate the transfer function of an optical receiver composed by a photodiode and a FET input operational amplifier as a current to voltage converter. According to the theory of low-pass filters, the receiver bandwidth and quality factor are here analytically evaluated, proposing design solutions and their related sensitivity to eventual parameter fluctuations. We exemplify the combined action of photodetection and filtering comparing the analytical expression with full numerical SPICE simulations

Novel Resistorless Mixed-Mode PID Controller with Improved Low-Frequency Performance

This paper introduces a new resistorless mixed-mode proportional-integral-derivative (PID) controller. It employs six simple transconductors and only two grounded capacitors. The proposed PID controller offers several advantageous features of resistorless configuration, use of grounded capacitors, independent electronic-tuning characteristic of its parameters, and mixed-mode operation such as current, transimpedance, transadmittance, and voltage modes. The parasitic element effects of the transconductors on the proposed controller are investigated and the improved low-frequency performance of the proposed controller is then discussed. As applications, the proposed controller is demonstrated on two closed-loop systems. The PSPICE simulations with TSMC 0.18µm CMOS process and ±0.9V supply voltage verify the theoretical analysis