- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Enhanced hydrogen sensing properties of Pd-coated SnO2 nanorod arrays in nitrogen and transformer oil
摘要： We report enhanced sensing properties of Pd-coated SnO2 nanorod (NR) arrays for detecting H2 gas in N2 and dissolved in transformer oil. The Pd nanoparticles were coated on randomly ordered vertical SnO2 NR arrays by the glancing angle deposition (GLAD) method, which utilizes an electron-beam evaporator and a DC magnetron sputtering system. The Pd-coated SnO2 NR arrays exhibited high response (104 at 1% H2) in N2. Pd-coated SnO2 NR arrays were immersed and in mineral oil that contains various concentrations of dissolved H2 and the electrical response was measured. We found that the Pd-coated SnO2 NR arrays showed superior response (R = ?96), low detection limit (0.3 ppm), and fast response times (300 s). The Pd-coated SnO2 NR arrays had a temperature coefficient of resistance (TCR) of 3.69 × 10-3 °C-1 at various oil temperatures (20–80 °C), indicating good thermal stability at high temperatures. The sensing mechanism of the Pd-coated SnO2 NR arrays was also demonstrated by using changes in the Schottky barrier height at the Pd/SnO2 interface upon exposure to H2.
关键词： Pd,SnO2,Transformer oil,Nanorod arrays,Hydrogen sensing
更新于2025-09-19 17:15:36
-
Favorable manipulation of macrophage/endothelial cell’s functionality and their cross-talk on silicon-doped titania nanotube arrays
摘要： Inflammatory reaction and the functionality of endothelial cells (ECs) on the surface of coronary stents are critical in the prevention of the in-stent restenosis and subsequent neoatherosclerosis. However, the interactions between immune cells and ECs on modified coronary stent surface have long been underestimated. In the present study, silicon (Si)-doped titania nanotube arrays (TNA-Sis) were obtained by a facile anodization of magnetron-sputtered Ti-Si coatings. The synergetic effect of titania nanotube arrays (TNAs) and chemical cues (Si) on the functionality of macrophages (MΦs) /ECs and their cross-talk were investigated. The results indicated that TNA-Sis, in comparison with TNAs alone, not only promoted ECs initial vitality, enhanced the expression of vascular endothelial growth factor (VEGF) and nitric oxide (NO), activated multiple cell signaling pathways (vWF, PECAM, eNOS), but also induced a favorable immune response through the polarization of MΦs to a pro-healing M2 phenotype via the activation of cell autophagy, resulting in the downregulation of inflammatory reaction. The beneficial immune response further facilitated the cross-talk between ECs and MΦs with a profoundly increased functionality of EC on TNA-Sis surfaces. This study demonstrated that the surface coating of TNA-Sis for the coronary stent may be a promising strategy to prevent in-stent restenosis.
关键词： Endothelial cells,Coronary stents,Silicon,Macrophages,Titania nanotube arrays
更新于2025-09-19 17:15:36
-
[IEEE 2019 IEEE 1st International Conference on Energy, Systems and Information Processing (ICESIP) - Chennai, India (2019.7.4-2019.7.6)] 2019 IEEE 1st International Conference on Energy, Systems and Information Processing (ICESIP) - PV fed LLC-LC Multi-resonant Converter based LED Driver
摘要： In many circumstances, the conventional ultrasonic liquid-level detection presents the unreliable estimations due to the dynamically changed liquid level. In addition, there are circumstances where the level change involves not only the fluctuation but also the rise or fall of liquid level. To improve the measuring accuracy of liquid level using the ultrasonic method in dynamically changed level case, an attractive ultrasonic method, named the liquid-level detection based on the multiple-input multiple-output ultrasonic transducer array, is proposed in this paper. This method is different from the early ultrasonic liquid-level detections, including those that utilize transducer array. Based on the virtual element technology, the method employs the multitransducer array to achieve the reduction of system complexity and cost, and then applies the synthetic aperture technology to realize rapid samples of liquid level. Besides, one adaptive searching scheme of focused position in beamforming of synthetic aperture in each scanning direction is optimized to get the high precise samples of liquid level. The proposed method is verified by simulation and a real system, and compared with the conventional single-channel approach. We still proposed a simulation method of ultrasonic echo signal from liquid level based on the boundary-layer theory and the ultrasonic scattering theory. The simulated and actual measurement results demonstrate that the proposed method is obviously superior to the conventional approach. Meanwhile, the factors influencing on the proposed method are investigated by simulation also. The investigations reveal that the focus position in beamforming, the SNR of echo signal, and the wave size of liquid level have impact on the suggested method. However, it is indicated that the good performance of the proposed method remains, provided that the focus in beamforming is properly set in every scanning direction and the noise of echo signal is effectively controlled.
关键词： level measurement,multiple-input multiple-output (MIMO) systems,Acoustics,transducers,measurement errors,arrays
更新于2025-09-19 17:13:59
-
[IEEE 2019 IEEE 8th International Conference on Advanced Optoelectronics and Lasers (CAOL) - Sozopol, Bulgaria (2019.9.6-2019.9.8)] 2019 IEEE 8th International Conference on Advanced Optoelectronics and Lasers (CAOL) - Machining Error Influnce on Stress State of Conical Thread Joint Details
摘要： This paper proposes a novel scalable digit-serial inverter structure with low space complexity to perform inversion operation in GF(2m) based on a previously modi?ed extended Euclidean algorithm. This structure is suitable for ?xed size processor that only reuse the core and does not require to modulate the core size when m modi?ed. This structure is extracted by applying a nonlinear methodology that gives the designer more ?exibility to control the processing element workload and also reduces the overhead of communication between processing elements. Implementation results of the proposed scalable design and previously reported ef?cient designs show that the proposed scalable structure achieves a signi?cant reduction in the area ranging from 83.0% to 88.3% and also achieves a signi?cant saving in energy ranging from 75.0% to 85.0% over them, but it has lower throughput compared to them. This makes the proposed design more suitable for constrained implementations of cryptographic primitives in ultra-low power devices such as wireless sensor nodes and radio frequency identi?cation (RFID) devices.
关键词： ?nite ?eld inversion,Scalable systolic arrays,ASIC,ultra-low power devices,hardware security
更新于2025-09-19 17:13:59
-
[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Shadow masking and tunnel contacts: A low cost process for high efficiency IBC solar cells
摘要： One of the main vulnerabilities of GNSS receivers jamming is their exposure to intentional or unintentional signals, which could even cause service unavailability. Several alternatives to counteract these effects were proposed in the literature, being the most promising those based on multiple antenna architectures. This is specially the case for high-grade receivers used in applications requiring reliability and robustness. This article provides an overview of the possible receiver architectures encompassing antenna arrays and the associated signal processing techniques. Emphasis is also put on the most typical implementation issues found when dealing with such technology. A thorough survey is complemented with a set of experiments, including real data processing by a working prototype, which exemplifies the above ideas.
关键词： array signal processing,Adaptive arrays,receiving antennas,satellite navigation systems,global positioning system,radio navigation,robustness,availability,electromagnetic interference
更新于2025-09-19 17:13:59
-
[IEEE 2019 16th China International Forum on Solid State Lighting & 2019 International Forum on Wide Bandgap Semiconductors China (SSLChina: IFWS) - Shenzhen, China (2019.11.25-2019.11.27)] 2019 16th China International Forum on Solid State Lighting & 2019 International Forum on Wide Bandgap Semiconductors China (SSLChina: IFWS) - Optimal thermal design of LED automotive headlamp with the response surface method
摘要： One of the main vulnerabilities of GNSS receivers is their exposure to intentional or unintentional jamming signals, which could even cause service unavailability. Several alternatives to counteract these effects were proposed in the literature, being the most promising those based on multiple antenna architectures. This is specially the case for high-grade receivers used in applications requiring reliability and robustness. This article provides an overview of the possible receiver architectures encompassing antenna arrays and the associated signal processing techniques. Emphasis is also put on the most typical implementation issues found when dealing with such technology. A thorough survey is complemented with a set of experiments, including real data processing by a working prototype, which exemplifies the above ideas.
关键词： array signal processing,Adaptive arrays,receiving antennas,satellite navigation systems,global positioning system,radio navigation,robustness,availability,electromagnetic interference
更新于2025-09-19 17:13:59
-
Efficient Nanorod Arrays Perovskite Solar Cells: A Suitable Structure for High Strontium-Substitution in a Nature Environment
摘要： Organic-inorganic hybrid perovskite solar cells (PSCs) have become a research hotspot because of their excellent power conversion efficiency (PCE), but the presence of toxic lead (Pb) in perovskite film has significantly limited their commercial application. In this study, using a TiO2 nanorod arrays (TNRAs) as the electron transport layer (ETL), strontium chloride (SrCl2) was chosen to fabricate lead-less PSCs in air environment (relative humidity, RH=50%) by a simple two-step spin-coating method. The influence of introduced strontium (Sr) on the perovskite films and cell properties was systematically investigated by various characterization methods. With increasing Sr substitution amount from 0 to 15 mol%, the formed perovskite films with a compact structure and a large crystalline size essentially remained invariable, while residual PbI2 was reduced, which is beneficial for the cell performance. The optimal PCE of 16.08% (average PCE = 15.37%) was obtained for the 5 mol% Sr-substituted PSCs because of the enhanced charge extraction from the perovskite film to the TNRAs and the suppressed charge recombination in the PSC. Both the humidity and thermal stability of the Sr-substituted PSCs were improved. More importantly, the 15 mol% Sr-substituted PSCs still exhibited a PCE of 15.09% in air (RH = 50%), maintaining 99% of the cell efficiency of the pristine (0 mol% Sr) PSC (15.27%), suggesting that the TNRAs structure is suitable for synthesis of high Sr-substituted lead-less PSCs.
关键词： Lead-less perovskite solar cells,TiO2 nanorod arrays,Defect density,Strontium substitution,Recombination
更新于2025-09-19 17:13:59
-
Improved electro-optic chaotic system with nonlinear electrical coupling
摘要： Design disjunction is developed to offer a broad coverage, high resolution, and low overhead approach to online diagnosis and recovery of recon?gurable fabrics. Design disjunction leverages the condensed diagnosability of T logic resources to achieve self-recovery using partial recon?guration in O(log T ) steps. Recon?guration is guided by the constructive property of f-disjunctness which forms O(log T ) resource groups at design-time. Resolution of f simultaneous resource faults is shown to be guaranteed when the resource groups are mutually f-disjunct. This extends run-time fault resilience to a large resource space with certainty for up to f faults using a decision-free resolution process that also provides a high likelihood of identifying the fault’s location to a ?ne granularity. Finally, design disjunction is parameterized to accommodate the low coverage issue of functional testing for which inarticulate tests can otherwise impair fault isolation. Experimental results for MCNC and ISCAS benchmarks on a Xilinx 7-series ?eld programmable gate array (FPGA) demonstrate f-diagnosability at the individual slice level with a minimum average isolation accuracy of 96:4 percent (94:4 percent) for f ? 1 (f ? 2). Results have also demonstrated millisecond order recovery with a minimum increase of 83:6 percent in fault coverage compared to N-modular redundancy (NMR) schemes. Recovery is achieved while incurring an average critical path delay impact of only 1:49 percent and energy cost roughly comparable to conventional two-MR approaches.
关键词： online test,run-time fault diagnosis and recovery,design space exploration,Recon?gurable logic devices,autonomous fault handling,fault-tolerant systems,?eld programmable gate arrays
更新于2025-09-19 17:13:59
-
[IEEE 2019 IEEE International Conference on Microwaves, Antennas, Communications and Electronic Systems (COMCAS) - Tel-Aviv, Israel (2019.11.4-2019.11.6)] 2019 IEEE International Conference on Microwaves, Antennas, Communications and Electronic Systems (COMCAS) - Advances in Slotted Waveguide Array Antenna Technology
摘要： We review the state of the art of slotted waveguide array antenna technology. Design and analysis techniques of slot arrays in standard rectangular waveguides are discussed first. Subsequently slots cut in ridge waveguides, iris excited waveguides, strip lines, radial waveguides and gap waveguides are addressed. Some applications of slot arrays and manufacturing techniques are also briefly reviewed.
关键词： Slot arrays,antenna theory,slotted waveguide,antenna design,array analysis and optimization
更新于2025-09-19 17:13:59
-
Watt-Level CW Ti:Sapphire Oscillator Directly Pumped with Green Laser Diodes Module
摘要： A watt-level directly diode-pumped continuous-wave (CW) Ti:Sapphire oscillator was demonstrated for the first breakthrough by a high-power green laser-diode-pumped module employing the technologies of beam shaping, beam collimation, polarization beam combining, and fiber coupling. A 1.36-W output power and 10.6% of slope efficiency were obtained based on the double-concave (DC) cavity configuration. This is the highest CW output power from Ti:Sapphire (Ti:S) oscillator directly pumped by green laser diodes (LDs) reported so far.
关键词： Semiconductor laser arrays,Optical pumping,Optical design techniques,Diode lasers
更新于2025-09-19 17:13:59