- 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
-
Effect of structures and substrate temperatures on BaZn0.06Bi0.94O3- perovskite-based NTC thermistor thin films
摘要: Negative temperature coefficient (NTC) thermistor thin films based on perovskite-type BaBiO3 (BB) and BaZn0.06Bi0.94O3-δ (BZB) were successfully prepared by radio frequency (RF) magnetron sputtering method on Pt substrate. The crystal structure and grain morphology of the BZB and BB films deposited at different substrate temperatures (25–200 °C and 200 °C, respectively) were examined by X-ray diffraction (XRD) and atomic force microscope (AFM). The substrate temperature had a significant influence on the crystallinity and phase structure, in which the main crystalline phases with the cubic and tetragonal BaBiO3-based perovskite structures could be obtained on the substrate temperatures of 100 °C and 200 °C, respectively. On the other hand, the electrical properties were analyzed by measuring the resistance temperature (ρ-T) characteristics, and all the thin films exhibited good NTC thermistor characteristics. In addition, the grain (Rg) and grain boundary (Rgb) contribution to the total resistance were estimated by three parallel R-CPE equivalent circuits in series, in which the main contribution of resistance for BZB thin film deposited at 200 °C was derived from Rg response rather than that in Rgb at the higher temperature range. This was one of the most important reasons why this sample had a good NTC behavior, and this result was confirmed by the current-voltage (I-V) characteristics analysis. For the BB film, the room-temperature resistivity (ρ25) was 1540 Ω cm (B25/85 –3240 K), while the ρ25 value decreased to approximately 1156 Ω cm (B25/85 –3183 K) for BZB film deposited at a same substrate temperature (200 °C). This is mainly due to the change in crystal structural characteristics. It is believed that the substitution of Zn2+ for BB thin films deposited at an appropriate temperature will be useful for low-resistance applications as novel thin film NTC thermistors.
关键词: Substrate temperature,NTC thermistor,Electrical properties,BaBiO3,Thin film
更新于2025-09-23 15:23:52
-
A Novel Method for Compensating Temperature Measurement Error Caused by Dust Using Infrared Thermal Imager
摘要: The dust generated in industrial processes has a serious impact on the accuracy of infrared thermometry, which is also the main reason for the limited use of infrared industrial temperature measurement methods applications. To reduce the influence of dust on infrared temperature measurement, this paper proposes a new method for compensating measurement error caused by dust. Firstly, the source of temperature measurement error caused by dust is analyzed, and a compensation method, in which the dust transmittance is important but difficult to determine, is proposed based on the principle of infrared temperature measurement. Then, to solve the difficulty of determining dust transmittance, we define a spatial temperature level co-occurrence matrix and a neighboring temperature level dependence matrix which can be utilized to extract the infrared thermal image’s texture features affected by dust. Finally, by integrating stacked denoising auto-encoder with optimized parameters and support vector regression, a dust transmittance model is established to determine dust transmittance based on the extracted features. Experimental results indicate that the proposed compensation method can reduce the influence of dust on infrared thermal imager’s accuracy effectively.
关键词: temperature measurement,dust transmittance,dust,texture feature,Compensation model,infrared thermal imager
更新于2025-09-23 15:23:52
-
[IEEE 2018 IEEE International Power Electronics and Application Conference and Exposition (PEAC) - Shenzhen, China (2018.11.4-2018.11.7)] 2018 IEEE International Power Electronics and Application Conference and Exposition (PEAC) - Investigation of Temperature-Dependent Electrical Behavior and Trap Effect in AlGaN/GaN HEMT
摘要: Temperature-dependent electrical behavior and trap effect in AlGaN/GaN high-electron mobility transistors (HEMT) were investigated at temperatures ranging from 25°C to 125°C. The experiment results show that transfer curves negatively shift and transconductance degrades with the increase in temperature at DC and pulsed conditions, meanwhile, gate leakage current increases significantly. Besides, the shift variation of pulsed transfer curves becomes larger at the elevated temperature and static bias states. This mechanism could be attributed to the enhancement of electron-assisted tunneling ability and easily escaping from the traps for trapped electrons at higher temperature. These traps were confirmed on the base of low frequency noise technique under different temperatures, and the extracted activation energy is 0.521eV for the present devices. The above results may provide useful guidance for design and application of the AlGaN/GaN HEMT.
关键词: Trap Effect,GaN,HEMT,Low Frequency Noise,Temperature
更新于2025-09-23 15:23:52
-
Investigation of an in-line fiber Mach–Zehnder interferometer based on peanut-shape structure for refractive index sensing
摘要: An in-line fiber Mach–Zehnder interferometer (MZI) for refractive index (RI) sensing was proposed, and the interferometer was fabricated by cascading two peanut-shape structures in the single mode fiber using the commercial fusion splicer. A model of the peanut-shape profile was used to calculate the power distribution of the modes in the device. The RI sensing performances of the peanut-shape structure in-line fiber MZIs with two different arm length (30 and 100 mm) were investigated. As the sensor with a short arm length of 30 mm, the RI sensitivity of ?67.355 nm/RIU was achieved for the RI range of 1.33–1.37. As the sensor with a long arm length of 100 mm, the simultaneous RI and temperature measurement was realized to eliminate the temperature and RI cross sensitivity, and the highest RI and temperature sensitivities of ?67.953 nm/RIU and 0.073 nm/?C were obtained, respectively.
关键词: Simultaneous refractive index and temperature measurement,Optical fiber sensor,Refractive index measurement,Mach–Zehnder interferometer,Peanut-shape structure
更新于2025-09-23 15:23:52
-
Intracortical neural stimulation with untethered, ultrasmall carbon fiber electrodes mediated by the photoelectric effect
摘要: Objective: Neural stimulation with tethered, electrically activated probes is damaging to neural tissue and lacks good spatial selectivity and stable chronic performance. The photoelectric effect, which converts incident light into electric potential and heat, provides an opportunity for a tetherless stimulation method. We propose a novel stimulation paradigm that relies on the photoelectric effect to stimulate neurons around a free-floating, ultrasmall (7-8μm diameter) carbon fiber probe. Methods: A 2-photon microscope induced photo-stimulation with a laser. Chronoamperometry and chronopotentiometry were used to characterize the electrochemical properties of photo-stimulation, while the fluorescence of Rhodamine-B was used to quantify temperature changes. Results: Photo-stimulation caused a local cathodic potential pulse with minimal leakage current. Stimulation induced voltage deflections of 0.05 - 0.4V in vitro, varying linearly with the power of the laser source (5 – 40 mW). Temperature increases in the immediate vicinity of the electrode were limited to 2.5°C, suggesting that this stimulation modality can be used without inducing heat damage. Successful stimulation was supported in vivo by increased calcium fluorescence in local neurons at stimulation onset in a transgenic GCaMP-3 mouse model. Furthermore, cells activated by photo-stimulation were closer to the electrode than in electrical stimulation under similar conditions, indicating increased spatial precision. Conclusion: Our results support the hypothesis that the proposed photoelectric method is effective for neural stimulation. Significance: Photoelectric stimulation is precise and avoids the need for a potentially destructive tether, making it a promising alternative to electrical stimulation.
关键词: GCaMP,electrochemistry,neuromodulation,photovoltaic effect,2-photon microscopy,temperature-dependent,fluorescence
更新于2025-09-23 15:23:52
-
Effect of temperature on digital images of speckle patterns generated by a metallic rough surface
摘要: It is well known that roughness can be inferred from digital images of speckle patterns generated by illuminated rough surfaces, by analyzing parameters such as fractal dimension, lacunarity and correlation, to cite a few. In this article, we investigate the effect of temperature on the speckle pattern generated by the light scattered from a metallic rough surface. We show that fractal dimension is less sensitive to temperature changes than are lacunarity and correlation, and provide information about which method is more suitable for processing the speckle patterns produced by rough surfaces under temperature variation.
关键词: Speckle pattern,Fractal dimension,Correlation,Roughness,Lacunarity,Temperature
更新于2025-09-23 15:23:52
-
High-<formula><tex>$T_\rm{c}$</tex></formula> Superconducting Fourth-Harmonic Mixer using a Dual-Band Terahertz On-Chip Antenna of High Coupling Efficiency
摘要: This paper presents a dual-band on-chip antenna coupled high-Tc superconducting (HTS) Josephson-junction sub-terahertz (THz) fourth-harmonic mixer. The antenna utilizes a couple of different structured twin-slots to enable the resonant radiations at two frequencies, and integrates a well-designed coplanar waveguide (CPW) network for achieving good radiation coupling and signal isolation characteristics. The electromagnetic (EM) simulations show that coupling efficiencies as high as -4 dB and -3.5 dB are achieved for the 160-GHz and 640-GHz operating frequency bands, respectively. Based on this dual-band antenna, a 640-GHz HTS fourth-harmonic mixer is developed and characterized in a range of operating temperatures. The mixer exhibits a measured conversion gain of around -18 dB at 20 K and -22 dB at 40 K respectively. The achieved intermediate-frequency (IF) bandwidth is larger than 23 GHz. These are the best results reported for HTS harmonic mixers at comparable sub-THz frequency bands to date.
关键词: high-temperature superconductor Josephson junction,dual-band on-chip antenna,terahertz wireless applications,fourth-harmonic mixing,Terahertz mixer
更新于2025-09-23 15:23:52
-
Facile synthesis of thermal responsive fluorescent poly(imino ether sulfone): Nondestructive detection of Tg and erasable thermal imaging
摘要: A novel heat-resistant fluorescent polymer poly(imino ether sulfone) (PIES) as thermally erasable and writable imaging material has been synthesized via a facile nucleophilic substitution polycondensation reaction. Taking advantage of the tenability of the 'push-pull' π-electron mode by changing temperatures, the Tg of PIES film can be 'naked eye' nondestructively detected by taking advantage of the visual fluorescence quenching.
关键词: Nondestructive detection,Poly(imino ether sulfone),High performance polymer,Glass transition temperature
更新于2025-09-23 15:23:52
-
[IEEE 2018 IEEE International Reliability Physics Symposium (IRPS) - Burlingame, CA (2018.3.11-2018.3.15)] 2018 IEEE International Reliability Physics Symposium (IRPS) - High-temperature and high-field cycling reliability of PZT films embedded within 130 nm CMOS
摘要: We present a systematic reliability study of PZT polarization retention after exposure to high temperatures and high-field cycling. After a 260 °C Pb-free solder assembly reflow-like exposure, a signal margin of >10 μC/cm2 is achieved at a read voltage of 1 V. Extraction of the Preisach distribution after thermal depolarization and restore exhibits an increase in the positive coercive voltage by 45 % while the negative coercive voltage shows minimal deviation (<7 %). Under accelerated aging via high electric fields (2.4 V), maximum wake-up at 106 cycles followed by fatigue >108 cycles is observed. Asymmetry in coercive voltage is minimized after wakeup and remanent polarization maximized. After fatigue, a signal margin >10 μC/cm2 is maintained for read voltages >0.8 V.
关键词: high-temperature bake,Ferroelectric capacitor,thermal depolarization,cycling,data retention,imprint
更新于2025-09-23 15:23:52
-
Achieving high-resolution thermal imagery in low-contrast lake surface waters by aerial remote sensing and image registration
摘要: A two-platform measurement system for realizing airborne thermography of the Lake Surface Water Temperature (LSWT) with ~0.8 m pixel resolution (sub-pixel satellite scale) is presented. It consists of a tethered Balloon Launched Imaging and Monitoring Platform (BLIMP) that records LSWT images and an autonomously operating catamaran (called ZiviCat) that measures in situ surface/near surface temperatures within the image area, thus permitting simultaneous ground-truthing of the BLIMP data. The BLIMP was equipped with an uncooled InfraRed (IR) camera. The ZiviCat was designed to measure along predefined trajectories on a lake. Since LSWT spatial variability in each image is expected to be low, a poor estimation of the common spatial and temporal noise of the IR camera (nonuniformity and shutter-based drift, respectively) leads to errors in the thermal maps obtained. Nonuniformity was corrected by applying a pixelwise two-point linear correction method based on laboratory experiments. A Probability Density Function (PDF) matching in regions of overlap between sequential images was used for the drift correction. A feature matching-based algorithm, combining blob and region detectors, was implemented to create composite thermal images, and a mean value of the overlapped images at each location was considered as a representative value of that pixel in the final map. The results indicate that a high overlapping field of view (~95%) is essential for image fusion and noise reduction over such low-contrast scenes. The in situ temperatures measured by the ZiviCat were then used for the radiometric calibration. This resulted in the generation of LSWT maps at sub-pixel satellite scale resolution that revealed spatial LSWT variability, organized in narrow streaks hundreds of meters long and coherent patches of different size, with unprecedented detail.
关键词: Lake surface water temperature,Uncooled infrared camera,Image registration,Lake Geneva,Thermal imagery,Aerial remote sensing
更新于2025-09-23 15:23:52