基于CMOS集成有源传感器的新型高能物理粒子轨迹追踪器

本文研究了一个采用标准0.35μm CMOS 工艺制造的新型高能物理粒子轨迹追踪器.这个新型的追踪器运用CMOS有源像素传感器技术(CMOS Monolithic Active Pixel Sensors,MAPS)将信号的探测与处理电路集成在一起,在像素的内部实现了相关双次采样操作(Correlated Doubled Sampling,CDS).实验芯片包含一个128行×32列的像素矩阵,其中,像素的大小为25×25μm².通过采用放射源⁵⁵Fe的测定, 得到像素的等效输入随机噪声 (Temporal Noise) 仅为12个电子而固定噪声(Fixed Pattern Noise,FPN)仅为4个电子.传感器的电荷-电压转换系数(Charge-to-Voltage conversion Factor,CVF)为60μV/e^-.测试中,芯片的信号读取速度达到了12μs/帧.     

Pulsed Laser Ablation of Tin Oxide Nanoparticles in Liquid for Optoelectronic Devices

Silicon - Laser ablation of tin oxide (SnO2) nanoparticles (NPs) was carried out by irradiation of tin target in methanol and aqueous NaCl solutions with nanosecond laser pulses. X-ray diffraction...     

Effects of Al on the Phase Volume Fractions and Wear Properties in the AlxCoCrFeMoNi High Entropy Alloy System

Metals and Materials International - A detailed investigation was carried out to study the effect of Al on the phase volume fractions and wear properties in the AlxCoCrFeMoNi high entropy alloy...     

Determination of thermo-electrical properties in Sn based alloys

The variation of thermal conductivity of solid phase versus temperature for Sn-21 wt.% Bi, Sn-25 wt.% In and Sn-35 wt.% In-26 wt.% Bi alloys were measured with a radial heat flow apparatus. From the graphs of thermal conductivity versus temperature, the thermal conductivity of the solid phases at their melting temperatures and the thermal temperature coefficients for the same alloys were obtained. The ratios of thermal conductivity of liquid phase to solid phase for the same materials were measured with a Bridgman type directional solidification apparatus. The variations of electrical conductivity of solid phases versus temperature for the same alloys were determined from the Wiedemann-Franz law by using the measured values of thermal conductivity. From the graphs of electrical conductivity versus temperature, the electrical temperature coefficients for the same alloys were also determined. According to present experimental results it can be concluded that the thermal and electrical conductivity of Sn based alloys depend on the thermal and electrical conductivity of the alloying elements. If the thermal and electrical conductivity of the alloying elements are lower than the thermal conductivity of Sn, the thermal conductivity of Sn based alloys decreases, whereas, otherwise, it increases.     

Electrochemical oxidation of Basic Blue 3 dye using a diamond anode: evaluation of colour,COD and toxicity removal

BACKGROUND: Textile industries generate considerable amounts of waste‐water, which may contain strong colour, suspended particles, salts, high pH and high chemical oxygen demand (COD) concentration. The disposal of these coloured wastewaters poses a major problem for the industry as well as a threat to the environment. In this study, electrochemical oxidation of Basic Blue 3 (BB3) dye was studied in a bipolar trickle tower (BTT) reactor using Raschig ring shaped boron‐doped diamond (BDD) electrodes in recirculated batch mode. The effects of current density, temperature, flow rate, sodium sulfate concentration (Na₂SO₄) as supporting electrolyte, and initial dye concentration were investigated. RESULTS: The best experimental conditions obtained were as follows: current density 0.875 mA cm^?2, temperature 30 °C, flow rate 109.5 mL min^?1, Na₂SO₄ concentration 0.01 mol L^?1. Under these conditions, 99% colour and 86.7% COD removal were achieved. Toxicity tests were also performed on BB3 solutions under the best experimental conditions. CONCLUSION: Based on these results, the BDD anode was found to be very successful for the simultaneous degradation of BB3 and removal of COD. Additional toxicity test results also showed that electrochemical treatment using a BDD Raschig ring anode in a BTT reactor is an effective way of reducing toxicity as well as removing colour and COD. Copyright © 2010 Society of Chemical Industry     

Treatment of dairy industry wastewater by EC and EF processes using hybrid Fe?Al plate electrodes

BACKGROUND: In this study electrochemical treatment of dairy industry wastewater (DW) was investigated using a combined electrode system consisting of iron and aluminum as sacrificial electrodes. The dairy industry generates strong wastewaters characterized by high biological oxygen demand and chemical oxygen demand concentrations. Dairy industry waste effluents are concentrated in nature, and the main contributors of organic load to these effluents are carbohydrates, proteins and fats originating from the milk. Since dairy waste streams contain high concentrations of organic matter, these effluents may cause serious environmental problems. RESULTS: A pole changer device was employed to change polarization in given time intervals to generate iron and aluminum based coagulants respectively. The effects of current density, initial pH, sodium sulfate (Na₂SO₄) and H₂O₂ concentrations on the removal efficiency were investigated. The best experimental conditions obtained in electrochemical studies were as follows: current density = 15 mA cm^?2, natural pH, without supporting electrolyte addition, H₂O₂ concentration = 3 × 1000 mg L^?1. Under these conditions, 79.2% COD removal from DW was achieved. CONCLUSION: According to the results, 20 min electrolysis is enough, since insignificant variations in COD removal were observed after this time. These methods were found to be successful for the treatment of DW. Copyright © 2011 Society of Chemical Industry     

Prestretching effect and recovery process of polyvinyl alcohol film crosslinked with tartaric acid

The tartaric acid (TA)/polyvinyl alcohol (PVA) composite films were prepared with various TA concentrations from 5 to 20 wt%. The crosslinking due to TA improved the tensile characteristics such as tensile strength and the Young's modulus, and thermal stability of the films. The addition of TA in PVA led to a decrease in the crystallinity. Application of prestretching or preliminary deformation resulted in significant changes in both stress–strain behavior and tensile characteristics of both pure PVA and TA/PVA composite films. Although low preextension levels such as 5% strain did not change much the tensile characteristics, higher preextension levels improved the tensile strength but decreased the extensibility of the films. The recovery processes of the stretched films consisted of a fast recovery process for which most of the recoverable elastic deformation is seen took place within almost 30 min and a time-dependent long-lasting recovery process continued in time very slowly, which resulted in undesirable residual deformation. It was also observed that increasing TA concentration accelerated the recovery process, hence, improved the recovery properties of PVA. The use of TA in the membrane applications can be considered to improve the mechanical properties and reusability of the membrane technology.