- 标题
- 摘要
- 关键词
- 实验方案
- 产品
过滤筛选
- 2019
- photovoltaic power generation system
- sensitivity analysis
- Monte Carlo
- fuzzy layering evaluation method
- Electrical Engineering and Automation
- Xi’an Jiaotong University
-
The Advantages of Spark Discharge Generation for Manufacturing of Nanoparticles with Tailored Properties
摘要： The number of nanoparticle-based products on the market is expected to increase considerably during the coming decades. For this to happen a solid supply of high-quality nanoparticles is needed. For metal nanoparticles no large-scale manufacturing method exists today but production using spark discharge generation is believed to be one of the most suitable candidates. Spark discharge generation offers several advantages over other methods and the ?rst steps towards scaling up have already been taken. In this paper the spark discharge generator concept is presented and its advantages are discussed. Examples of nanoparticle materials and applications for the as-generated particles are reviewed.
关键词： Nanoparticles,spark discharge generation,aerosols
更新于2025-09-09 09:28:46
-
Automated retinal imaging and trend analysis – a tool for health monitoring
摘要： Most current diagnostic devices are expensive, require trained specialists to operate and gather static images with sparse data points. This leads to preventable diseases going undetected until late stage, resulting in greatly narrowed treatment options. This is especially true for retinal imaging. Future solutions are low cost, portable, self-administered by the patient, and capable of providing multiple data points, population analysis, and trending. This enables preventative interventions through mass accessibility, constant monitoring, and predictive modeling.
关键词： next-generation imaging technology,mass accessibility,early disease indicators,predictive health assessment,predictive analysis
更新于2025-09-09 09:28:46
-
<b>Compatibility of Anfis controller and FPGA in solar power generation for a domestic oad
摘要： Among other soft computing techniques, the Adaptive Neuro Fuzzy Inference System (Anfis) gives a significant and advantageous result in solar power generation, especially in tracking the maximum power point. Due to the dynamic nature of solar irradiance and temperature, efficient energy conversion is not possible. However, advancements in the areas of artificial intelligence have made it possible to overcome the hurdles. The Maximum Power Point Tracking (MPPT) technique adopting the advantages of Anfis has been proven to be more successful with a fast dynamic response and high accuracy. The complete system is modeled using Matlab/Simulink; the hardware results are validated with the benefits of Field Programmable Logic Array (FPGA) instead of ordinary micro-controllers.
关键词： DC-AC power conversion,MPPT,FPGA,Anfis controller,solar power generation
更新于2025-09-09 09:28:46
-
A synergistic heterostructured ZnO/BaTiO3 loaded carbon photoanode in photocatalytic fuel cell for degradation of Reactive Red 120 and electricity generation
摘要： Photocatalytic fuel cell (PFC) is considered as a sustainable green technology which could degrade organic pollutant and generate electricity simultaneously. A synergistic double-sided ZnO/BaTiO3 loaded carbon plate heterojunction photoanode was fabricated in different ratios by using simple ultrasonication and mixed-annealed method. The double-sided design of photoanode allowed the lights irradiated at both sides of the photoanode. The ferroelectricity fabricated photoanode was applied in a membraneless PFC with platinum-loaded carbon as the cathode. Results revealed that the photoanode with 1:1 ratio of BaTiO3 and ZnO exhibited a superior photocatalytic activity among all the photoanodes prepared in this study. The heterojunction of this photoanode was able to achieve up to a removal efficiency of 93.67 % with a maximum power density of 0.5284 μW cm-2 in 10 mg L-1 of Reactive Red 120 (RR120) without any supporting electrolyte. This photoanode was able to maintain at high performance after recycling 3 times. Over loading of ZnO above 50% on BaTiO3 could lead to deterioration of the performance of PFC due to the charge defects and light trapping ability. The interactions, interesting polarizations of the photocatalysts and proposed mechanism of the n-n type heterojunction in the photoanode of ZnO/BaTiO3 was also discussed.
关键词： Photocatalytic fuel cell,Degradation,Reusability,ZnO/BaTiO3 heterojunction,Electricity Generation
更新于2025-09-09 09:28:46
-
Probing the upper band gap of atomic rhenium disulfide layers
摘要： Here, we investigate the ultrafast carrier dynamics and electronic states of exfoliated ReS2 films using time-resolved second harmonic generation (TSHG) microscopy and density functional theory (DFT) calculations. The second harmonic generation (SHG) of layers with various thicknesses is probed using a 1.19-eV beam. Up to ~13 nm, a gradual increment is observed, followed by a decrease caused by bulk interferometric light absorption. The addition of a pump pulse tuned to the exciton band gap (1.57 eV) creates a decay-to-rise TSHG profile as a function of the probe delay. The power and thickness dependencies indicate that the electron–hole recombination is mediated by defects and surfaces. The two photon absorptions of 2.38 eV in the excited state that are induced by pumping from 1.57 to 1.72 eV are restricted because these transitions highly correlate with the forbidden d–d intrasubshell orbital transitions. However, the combined usage of a frequency-doubled pump (2.38 eV) with wavelength-variant SHG probes (2.60–2.82 eV) allows us to vividly monitor the variations in TSHG profiles from decay-to-rise to rise-to-decay, which imply the existence of an additional electron absorption state (s-orbital) at an approximate distance of 5.05 eV from the highest occupied molecular orbital states. This observation was critically examined by considering the allowance of each electronic transition and a small upper band gap (~0.5 eV) using modified DFT calculations.
关键词： density functional theory,ReS2,time-resolved spectroscopy,ultrafast carrier dynamics,second harmonic generation
更新于2025-09-09 09:28:46
-
Nonlinear light generation in topological nanostructures
摘要： Topological photonics has emerged as a route to robust optical circuitry protected against disorder and now includes demonstrations such as topologically protected lasing and single-photon transport. Recently, nonlinear optical topological structures have attracted special theoretical interest, as they enable tuning of topological properties by a change in the light intensity and can break optical reciprocity to realize full topological protection. However, so far, non-reciprocal topological states have only been realized using magneto-optical materials and macroscopic set-ups with external magnets, which is not feasible for nanoscale integration. Here we report the observation of a third-harmonic signal from a topologically non-trivial zigzag array of dielectric nanoparticles and the demonstration of strong enhancement of the nonlinear photon generation at the edge states of the array. The signal enhancement is due to the interaction between the Mie resonances of silicon nanoparticles and the topological localization of the electric field at the edges. The system is also robust against various perturbations and structural defects. Moreover, we show that the interplay between topology, bi-anisotropy and nonlinearity makes parametric photon generation tunable and non-reciprocal. Our study brings nonlinear topological photonics concepts to the realm of nanoscience.
关键词： Silicon nanoparticles,Nonlinear light generation,Third-harmonic signal,Mie resonances,Topological nanostructures
更新于2025-09-09 09:28:46
-
Interferometry of dipole phase in high harmonics from solids
摘要： Understanding the temporal profiles of high harmonics is essential for their applications in attosecond science. Microscopically, the dipole phase plays an important role in determining the high-harmonic emission phase. In gas-phase high-harmonic generation, the tunnel-ionized electron spends much of its travel time in the continuum—far from the parent ion, where it accumulates the dipole phase. Therefore, the atomic dipole phase is largely independent of the target atom. In solid-state high-harmonic generation, since the driven electron experiences a periodic potential during the entire travel time, the dipole phase may depend on the electronic structures of source materials. Here, we employ an interferometric method to characterize high harmonics from magnesium oxide and quartz crystals. We measure material-dependent intensity-induced high-harmonic phase delays that we attribute to the intensity-induced changes in the dipole phase originating from the interband polarization. The material-dependent dipole phase can provide a robust platform for high-harmonic spectroscopy of solids.
关键词： dipole phase,solids,high-harmonic generation,attosecond science,interferometry
更新于2025-09-09 09:28:46
-
White light-emitting Dy <sup>3+</sup> -doped transparent chloroborosilicate glass: synthesis and optical properties
摘要： Dy3+-doped chloroborosilicate glasses with the composition 35.7SiO2-25.5B2O3-17BaO-3.4K2O-3.4Al2O3-15BaCl2 (mol%) were prepared using melt quenching technique. The glass transition temperature (Tg) was ~610°C. In UV-Vis-NIR absorption spectra characteristic absorption bands of Dy3+ appeared at 322, 347, 364, 388, 795 and 880 nm due to spectral transitions from the 6H15/2 level to various higher levels of Dy3+ ion. The excitation spectrum was recorded at within 200–550 nm by monitoring emissions at 576 nm. The excitation bands at 392, 428, 453 and 472 nm were attributed to the 6H15/2 → 4I13/2, 4G11/2, 4I15/2 and 4F9/2 transitions, respectively. Prominent emission bands were observed at wavelengths of 484, 576, 664 and 754 nm when excited at 447 nm. The bands correspond to the transitions 4F9/2→6H15/2, 4F9/2 → 6H13/2, 4F9/2 → 6H11/2, and 4F9/2 → 6H9/2 6F11/2 respectively. The emitted light from all the samples were found to be white. Their colour coordinates lie within the white range. The sample containing 0.5 wt% Dy2O3 emitted white light with the colour coordinates x=0.351, y=0.335, which are the very closest to pure white light and whose colour temperature of 4716 K is similar to daylight. Such white light-emitting transparent glasses promise to be enormously useful for various photonic applications.
关键词： white light generation,chloroborosilicate glass,Dy3+-doped glass,photoluminescence,absorption spectra
更新于2025-09-09 09:28:46
-
Dynamic theory of nanophotonic control of two-dimensional semiconductor nonlinearities
摘要： We introduce a Maxwell-Bloch simulation approach which self-consistently combines a microscopic description of the carrier and polarization dynamics of a transition-metal-dichalcogenide (TMDC) monolayer with a spatiotemporal full-wave time-domain simulation of Maxwell’s equations on the basis of a ?nite-difference time-domain (FDTD) method beyond the slowly varying amplitude or paraxial approximations. This offers a platform to realistically model, in particular, the typical ultrafast optical excitation experiments in micro- and nanocavities. Our simulations con?rm that the weak screening of the Coulomb interaction in TMDC monolayers yields pronounced exciton lines in the linear spectrum and we uncover the second-order nonlinearity represented in the semiconductor Maxwell-Bloch equations by an intraband dipole moment. This allows us to calculate the spectral shape of the exceptionally strong second-harmonic generation around the exciton lines of TMDC monolayers. We demonstrate that the second-harmonic signal can remarkably be further enhanced by several orders of magnitude through a suitably designed (one-dimensional) photonic microcavity. Due to its self-consistency, ?exibility, explicit spatio-temporal resolution on the nanoscale and the ready access to light ?eld and electron dynamics, our theory and computational approach is an ideal platform to design and explore spatiotemporal nonlinear and quantum dynamics in complex photonic or plasmonic micro- and nanostructures for optoelectronic, nanophotonic and quantum applications of TMDC monolayers.
关键词： second-harmonic generation,nonlinear optical response,TMDC monolayer,Maxwell-Bloch simulation,photonic microcavity
更新于2025-09-09 09:28:46
-
[IEEE 2018 43rd International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz2018) - Nagoya, Japan (2018.9.9-2018.9.14)] 2018 43rd International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz) - Optical Rectification of a 100W Average Power Ultrafast Thin-Disk Oscillator
摘要： We demonstrate THz generation by optical rectification in GaP crystals using excitation average power levels exceeding 100 W. The laser source is a state-of-the-art diode-pumped Yb:YAG modelocked thin-disk laser, capable of generating 120 W at 13.4 MHz directly from a one-box oscillator, without the need for any amplification stages. In this first demonstration, we measured a maximum average power of 78 μW at a central frequency of 0.8 THz. This first result shows that optical rectification of high average power (100 W class) ultrafast sources is within reach, and paves the way towards Watt-level, ultrafast laser pumped THz sources.
关键词： optical rectification,ultrafast lasers,GaP crystals,high average power,THz generation
更新于2025-09-09 09:28:46