- 标题
- 摘要
- 关键词
- 实验方案
- 产品
过滤筛选
- 2019
- 2018
- 2015
- low-temperature electronics
- junction field-effect transistors
- Bessel Function
- Coupling Coefficient
- Fusion temperature and Elongation speed
- Infrared Thermography
- Statistical Analysis
- Mean Temperature Difference
- Surface temperature distribution
- Diabetic Foot Complications
- Optoelectronic Information Science and Engineering
- Electronic Science and Technology
- Physics
- Don State Technical University
- China Jiliang University
- UIN Suska Riau
- BMS College of Engineering
- Dalhousie University
- Majmaah University
- Soochow University
- University of Riau
- Karnataka Institute of Endocrinology and Research (KIER)
- Southern Federal University
-
[IEEE 2018 2nd International Conference on Engineering Innovation (ICEI) - Bangkok (2018.7.5-2018.7.6)] 2018 2nd International Conference on Engineering Innovation (ICEI) - Schottky's Barrier Height of T91/Cr2O3 Heterojunction in Dry and Wet Conditions: Effects of WaterVapor Onto Accelerated High Temperature Oxidation
摘要： Increasing the operating temperature in thermal power plant will further accelerate the high temperature oxidation with the presence of water vapor. It is hypothesized that water vapor provides hydrogen that dissolves into the ferritic alloy susbstrate, hence altering their electronic state at the metal-semiconductor (oxide) interface. This study aims to quantitatively prove above postulation by comparing their Schottky’s Barrier Height (SBH) in dry and wet environment. The Schottky’s barrier was prepared by sputtering Cr2O3 onto the T91 boiler tube in high vacuum condition using RF power 150W for an hour. The T91/Cr2O3 junction was then connected with platinum wire for capacitance-voltage, C-V test at high temperature. The value of Vbi was used to calculate the SBH, which increase proportionately with built in voltage. It is clearly shown that the SBH value in wet condition is higher than that in dry condition by 10.3%. This is explained by the formation of space charge layer at metal/oxide interface due to dissolved hydrogen in metal, thus may change the transport property and accelerate the oxidation rate in water vapor.
关键词： T91 alloy,Cr2O3,Schottky’s barrier,High temperature oxidation
更新于2025-09-04 15:30:14
-
Best lighting for jeans, part 1: Optimising colour preference and colour discrimination with multiple correlated colour temperatures
摘要： In this study, two psychophysical experiments, one on colour preference and the other on colour discrimination, were conducted. To investigate the colour preference for blue jeans, 27 subjects with normal colour vision were asked to rate their visual appreciation of seven pairs of jeans with a colour gradient pattern. Nine LEDs, with uniformly sampled correlated colour temperature (CCT) values ranging from 2500 K to 6500 K, were used to illuminate the jeans. These lights produced a constant illuminance of approximately 200 lux, and their colour rendering indexes were between 79 and 91. In addition, using a Farnsworth-Munsell (FM)-100 Hue Test, the blue-region colour discrimination of 42 observers was assessed for the same type but with different CCTs (2500 K–6500 K, 1000 K interval). The results indicate that there is an optimum CCT of 5500 K for jeans, at which observers were found to exhibit the greatest capability for colour discrimination and the highest rating for colour preference. Interestingly, a significant gender difference was found in this study, which had not been observed in our previous work with quite similar experimental settings but different experimental objects. The findings of this study should provide a deeper understanding for the lighting design of shopping malls for jeans.
关键词： colour preference,correlated colour temperature,gender difference,blue jeans,colour discrimination
更新于2025-09-04 15:30:14
-
High Sensitive Directional Twist Sensor Based on a Mach–Zehnder Interferometer
摘要： A new type of Mach–Zehnder interferometer (MZI) is proposed to measure twist and temperature. The sensor contains a pretwisted taper and a ball. The pretwisted taper is made by pretwisted, and then, thermally tapering along a single-mode ?ber, to induce permanent spiral distortion in the ?ber. The experimental results indicate that the sensor has higher twist sensitivity. Twisting the sensor for counterclockwise and clockwise direction, the twist sensitivities of Dip 1584 nm are –0.378 and 0.083 nm/(rad/m), respectively, and the twist sensitivities of Dip 1685 nm are –0.117 and 0.089 nm/(rad/m), respectively. Meanwhile, the twist direction can be determined by the value of the twist sensitivities. The temperature sensitivities of Dip 1584 and Dip 1685 nm are 63 pm/°C and 74 pm/°C, respectively. The feasibility of measuring the torsion and temperature characteristics has been experimentally con?rmed. Thus, the proposed MZI sensor can be used to measure twist and temperature and discriminate twist direction.
关键词： twist,Mach–Zehnder interferometer,temperature,pre-twisted taper
更新于2025-09-04 15:30:14
-
Simultaneous measurements of temperature and pressure with a dual-cavity Fabry-Perot sensor
摘要： A fiber-optic dual-cavity Fabry-Perot interferometric sensor for the simultaneous measurement of temperature and pressure is proposed and experimentally demonstrated. The sensor cascades a fiber-optic intrinsic Fabry–Perot interferometer (IFPI) and an extrinsic Fabry–Perot interferometer (EFPI). The IFPI is used as the temperature sensor and the EFPI is used as the pressure sensor. The pressure sensor is based on a diaphragm-free structure, and can work stably at high temperature. Two optical path differences are interrogated simultaneously by using the fast Fourier transform-based white-light interferometry and the peak-to-peak method. Experimental results show that the proposed sensor exhibits a temperature sensitivity of 29.63 nm/°C within the temperature range of 40-1100 °C, and a pressure sensitivity of 1465.8 nm/MPa within the pressure range of 0-10 MPa at the room temperature.
关键词： pressure measurement,femtosecond laser micromachining,fiber optics sensors,Fabry-Perot interferometers,temperature measurement
更新于2025-09-04 15:30:14
-
Model Development for Threshold Voltage Stability Dependent on High Temperature Operations in Wide-Bandgap GaN-Based HEMT Power Devices
摘要： Temperature-dependent threshold voltage (Vth) stability is a significant issue in the practical application of semi-conductor power devices, especially when they are undergoing a repeated high-temperature operation condition. The Vth analytical model and its stability are dependent on high-temperature operations in wide-bandgap gallium nitride (GaN)-based high electron mobility transistor (HEMT) devices that were investigated in this work. The temperature effects on the physical parameters—such as barrier height, conduction band, and polarization charge—were analysed to understand the mechanism of Vth stability. The Vth analytical model under high-temperature operation was then proposed and developed to study the measurement temperatures and repeated rounds dependent on Vth stability. The validity of the model was verified by comparing the theoretical calculation data with the experimental measurement and technology computer-aided design (TCAD) simulation results. This work provides an effective theoretical reference on the Vth stability of power devices in practical, high-temperature applications.
关键词： high-temperature operation,gallium nitride (GaN),analytical model,high electron mobility transistors (HEMTs),threshold voltage (Vth) stability
更新于2025-09-04 15:30:14
-
Temperature Driven Phase Transition of Organic-Inorganic Halide Perovskite Single Crystals
摘要： Organic-inorganic halide perovskite single crystals undergo phase transition of being cubic, tetragonal, or orthorhombic depending on the temperature. We investigated the CH3NH3PbBr3?xIx single crystals grown by the inverse temperature crystallization method with temperature-dependent UV-Vis absorption and photoluminescence. From the temperature-dependent absorption measurement, the optical band gap is extracted by derivation of absorption spectrum fitting and Tauc plot. In our results, CH3NH3PbBr3?xIx single crystals show that an abrupt change in optical band gap, PL peak position and intensity appears around 120 K - 170 K regions, indicating the phase transition temperature.
关键词： Photoluminescence,Phase transition,Perovskite single crystal,Temperature-dependent absorption,Derivation of absorption spectrum fitting (DASF)
更新于2025-09-04 15:30:14
-
[IEEE 2018 13th European Microwave Integrated Circuits Conference (EuMIC) - Madrid, Spain (2018.9.23-2018.9.25)] 2018 13th European Microwave Integrated Circuits Conference (EuMIC) - Characterisation of GaAs pHEMT Transient Thermal Response
摘要： Transient gate resistance thermometry is employed to characterise the time domain response of a GaAs pHEMT under pulsed conditions. Self heating is observed from hundreds of nanoseconds to hundreds of milliseconds. A TFR-heated test structure is used to develop a 3-D ?nite-element thermal model that scales with power density and gate periphery. Thermal coupling between gate ?ngers in a multi-?nger device is measured, and then further investigated via simulation. The model’s application to thermal optimisation of devices and circuits is discussed.
关键词： MMICs,HEMTs,Gallium arsenide,thermal analysis,temperature measurement
更新于2025-09-04 15:30:14
-
[Advances in Chemical Engineering] Spatially Resolved Operando Measurements in Heterogeneous Catalytic Reactors Volume 50 || Spatio-Temporal Phenomena in Monolithic Reactors Measured by Combined Spatially-Resolved Mass Spectrometry and Optical Frequency Domain Reflectometry
摘要： Measuring the spatiotemporal temperature and reacting species concentrations of a reacting system under realistic conditions is essential to optimize the reactor design and operation. Conventional measurements of the inlet and outlet values provide only a partial picture of the reactor behavior. We describe the novel method coherent optical frequency domain reflectometry (c-OFDR) which provides unparalleled information about the spatiotemporal temperature in a catalytic reactor. c-OFDR launches a laser beam through an optical fiber positioned inside a reactor. The spatial dependence of temperature is determined through the measured spectral shift of reflected scattering light frequency. The advantages of c-OFDR include high spatial and temporal resolution (3 mm and 0.9 Hz), broad operating range (up to 800°C), noninvasive measurement (125 μm OD), stationary, and chemically resistant (gold-coated) sensor. In addition to describing the theory and standard operation of c-OFDR, we demonstrate c-OFDR for several applications involving reaction in a catalytic monolith during both steady-state and transient operation. The combination of c-OFDR with spatially resolved capillary inlet mass spectrometry (SpaciMS) provides detailed characterization of a catalytic reactor under periodic operation. Combined SpaciMS and c-OFDR successfully follow the cyclic lean/rich behavior during temperature programmed oxidation experiments. SpaciMS invasiveness is assessed through systematic measurement of the temperature by c-OFDR and concentration by SpaciMS. In an ideal adiabatic reactor, the temperature peak and complete reactant conversion should occur at the same position. Our experiments enabled generation of a map of operating conditions under which this did not occur which helps identify when the SpaciMS method is invasive.
关键词： reactor design,SpaciMS,catalytic reactor,spatiotemporal temperature,coherent optical frequency domain reflectometry
更新于2025-09-04 15:30:14
-
Synthesis and characterization of carbon-poor SiC nanowires via vapor-liquid-solid growth mechanism
摘要： Nanowires growth via vapor-liquid-solid mechanism leads to high-quality SiC nanowires. C content is key issue affecting the morphology and composition of SiC nanowires. Here, we report the synthesis and growth mechanism of 3C-SiC nanowires containing reduced amount of C, which are grown on single-crystal Si via pyrolysis of polycarbosilane (PCS) by adjusting pyrolysis temperature and precursor. SiC nanowires have a diameter of 50 nm, while their thickness is 43.75 μm. High-temperature stability of precursors with multiple side-chain groups has an impact on the reaction rate, in result the solid precursor state and pyrolysis temperature at 1350°C are beneficial to the formation of pure carbon-poor SiC nanowires.
关键词： precursor state,vapor-liquid-solid growth mechanism,SiC nanowires,pyrolysis temperature
更新于2025-09-04 15:30:14
-
Fabrication of high fill-factor aspheric microlens array by dose-modulated lithography and low temperature thermal reflow
摘要： A cost-effective fabrication method for high quality and high fill-factor aspheric microlens arrays (MLAs) is developed. In this method, the complex shape of aspheric microlens is pre-modeled via dose modulation in a digital micromirror device (DMD) based maskless projection lithography system. Digital masks for several bottom layers are replaced from circle to hexagon for the purpose of enhancing the fill-factor of MLAs, then a low temperature thermal reflow process is conducted, after which the average surface roughness of microlens is improved to * 0.427 nm while the pre-modeled profile keeps unchanged. Experimental results show that the fabricated aspheric MLAs have almost 100% fill-factor, high shape accuracy and high surface quality. The presented method may provide a promising approach for rapidly fabricating high quality and high fill-factor aspheric microlens in a simple and low-cost way.
关键词： high fill-factor,dose-modulated lithography,aspheric microlens arrays,surface roughness,low temperature thermal reflow
更新于2025-09-04 15:30:14