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- 2019
- photovoltaic power generation system
- sensitivity analysis
- Monte Carlo
- fuzzy layering evaluation method
- Electrical Engineering and Automation
- Xi’an Jiaotong University
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Nonlinear emission from silver-coated 3D hollow nanopillars
摘要： High aspect ratio metal nanostructures have been the subject of a number of studies in the past, due to their pronounced resonances in the infrared that can be exploited to enhance vibrational spectroscopies. In this work, we investigate the nonlinear optical response of both individual and closely-packed assemblies of vertical hollow Ag nanopillars upon excitation with ultrafast laser pulses. In particular, the analysis of their nonlinear emission spectra evidences an intense two photon photoluminescence (TPPL) emission and a neat signature of second harmonic generation (SHG). Given the relatively low background, this pronounced nonlinear emission could be employed as a local probe for analytes trapped at the surface of the nanopillar or flowing through it. For this reason, these nanostructures may become appealing building blocks in multi-purpose devices for nonlinear photonics and sensing.
关键词： Two Photon Photoluminescence,Ag Nanopillars,Localized Surface Plasmons,3D nanofabrications,Second Harmonic Generation
更新于2025-09-09 09:28:46
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New Candidate Multicomponent Chalcogenide Glasses for Supercontinuum Generation
摘要： Broadband supercontinuum (SC) generation requires host material attributes defined by both optical and physical properties and the material’s manufacturability. We review and define the trade-offs in these attributes as applied to fiber or planar film applications based on homogeneous glass property data, and provide a series of examples of how one might optimize such attributes through material compositional and morphology design. As an example, we highlight the role of varying composition, microstructure, and linear/nonlinear optical properties, such as transmittance, refractive index, and the multiphoton absorption coefficient, for a series of novel multicomponent chalcogenide glasses within a model GeSe2-As2Se3-PbSe (GAP-Se) system. We report key optical property variation as a function of composition and form, and discuss how such glasses, suitable for both fiber and planar film processing, could lend themselves as candidates for use in SC generation. We demonstrate the impact of starting glass composition and morphology and illustrate how tailoring composition and form (bulk versus film) leads to significant variation in linear, nonlinear, and dispersive optical property behavior within this system that enables design options that are attractive to optimization of desirable SC performance, based on optical composites.
关键词： photonics,infrared optical materials,chalcogenide glass science,supercontinuum generation,nonlinear optics
更新于2025-09-09 09:28:46
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Helicenic complexes of lanthanide: influence of f-element on the inter-system crossing efficiency and competition between luminescence and oxygen sensitization.
摘要： The coordination of a helicen functionalized bipyridine to various lanthanide complexes (Ln = Y, Eu, Yb, Gd) led to the formation of an isostructural series. The photophysical study indicated that non-emissive lanthanide act as heavy atoms strongly enhancing the singlet oxygen generation. We also demonstrated that sensitization of the f-f luminescence is in competition with singlet oxygen generation.
关键词： singlet oxygen generation,lanthanide,photodynamic therapy,luminescence,helicen
更新于2025-09-09 09:28:46
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Nanoscale Materials in Water Purification || Recent Progress in TiO2- and ZnO-Based Nanostructured Hybrid Photocatalysts for Water Purification and Hydrogen Generation
摘要： Energy and clean environmental conditions are the two basic requirements for the survival and progress of human civilization. The Industrial Revolution was a prime factor in the rapid development of human society. However, the industrial malpractices of waste disposal and extensive use of fossil fuels have led human society to face a number of challenges such as global warming, and water and air pollution. Also, the extensive use of pesticides in agriculture has led to high toxicity in soil and ground water, which can pose a big threat to human and wildlife [1]. A recent WHO report shows that about 3.7 million people globally die each year in the 21st century from the hazards of water and air pollution, and 92% of the world’s population still does not have access to pure water [2]. The fossil fuel resources are limited in their ability to cater to the energy demands of the growing world’s population and are on the verge of exhaustion in the near future. This has led to the fear of energy crises, which can prove fatal for human society. Hence, the search for an ultimate and clean energy source, as well as the development of technologies for the remediation of hazardous materials from the environment have become topics of high international concern. There have been several attempts to harness alternative energy sources such as wind, water tides, biomass and solar energy, etc., as well as to design methods for the remediation of environmental pollutants. Hence, the development of cleaner, low carbon, and sustainable technologies is a bigger challenge for scientists and engineers worldwide [3]. Some technologies have been developed to harness alternative energy sources, but these have proven either inefficient or too expensive. Also, efforts toward the removal of harmful environmental pollutants are either inefficient or have their own side effects [4]. Among renewable energy sources, solar energy is available in abundance and has the potential for overcoming current environmental impacts. However, its unavailability at night, and during rainy and foggy seasons make it difficult to properly harness. Hence, transforming energy from sunlight to the chemical energy of hydrogen through photocatalytic water splitting could be a more promising approach [5]. Solar energy is also gaining attention for water treatment. There have been a number of metal oxide-based photocatalysts prepared for degrading organic pollutants such as dyes and pesticides. This chapter stresses H2 generation through photocatalytic and photoelectrochemical water splitting and photocatalytic water treatment using two well-known photocatalysts, ZnO and TiO2.
关键词： ZnO,water purification,nanostructured hybrid photocatalysts,hydrogen generation,TiO2
更新于2025-09-09 09:28:46
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Spatially-Controllable Hot Spots for Plasmon-Enhanced Second-Harmonic Generation in AgNP-ZnO Nanocavity Arrays
摘要： Plasmon-enhanced second-harmonic generation (PESHG) based on hybrid metal-dielectric nanostructures have extraordinary importance for developing efficient nanoscale nonlinear sources, which pave the way for new applications in photonic circuitry, quantum optics, and biosensors. However, the relatively high loss of excitation energies and the low spatial overlapping between the locally enhanced electromagnetic field and nonlinear materials still limit the promotion of nonlinear conversion performances in such hybrid systems. Here, we design and fabricate an array of silver nanoparticle-ZnO (AgNP-ZnO) nanocavities to serve as an efficient PESHG platform. The geometry of AgNP-ZnO nanocavity arrays provides a way to flexibly modulate hot spots in three-dimensional space, and to achieve a good mutual overlap of hot spots and ZnO material layers for realizing efficient SH photon generation originating from ZnO nanocavities. Compared to bare ZnO nanocavity arrays, the resulting hybrid AgNP-ZnO design of nanocavities reaches the maximum PESHG enhancement by a factor of approximately 31. Validated by simulations, we can further interpret the relative contribution of fundamental and harmonic modes to Ag-NP dependent PESHG performances, and reveal that the enhancement stems from the co-cooperation effect of plasmon-resonant enhancements both for fundamental and harmonic frequencies. Our findings offer a previously unreported method for designing efficient PESHG systems and pave a way for further understanding of a surface plasmon-coupled second-order emission mechanism for the enhancement of hybrid systems.
关键词： second-harmonic generation,hybrid nanostructure,finite-difference time-domain,plasmonics
更新于2025-09-09 09:28:46
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Analysis of the Potential of Solar Energy Development inSaudi Arabia
摘要： Saudi Arabia has been exploring the potential of renewable energy for many years. Saudi authorities, scientists, and researchers view the generation of renewable energy as a viable long-term energy strategy. Despite this, because Saudi Arabia is one of the leading oil producing nations and relies heavily on it as a form of energy and source of income, solar energy has not been given much serious consideration. However, it has become more and more evident that for the continuing prosperity of the nation and the inevitable gradual decline in long-term oil production, it is essential to explore and invest in alternative energy sources. The main objectives of this research are: i) to establish the potential of solar energy generation as a suitable, cost-effective alternative to petroleum products. ii) to establish the potential for maximizing renewable power generation to support the supply grid. This paper presents an examination of various economic and technological aspects of generating solar energy in Saudi Arabia. Using some existing data on the amount of solar radiation, a seasonal multiple linear forecasting method is used to generate forecasts for electric energy generation potential for 32 cities. Results of this research demonstrate the desirability and economic feasibility of installing solar panel farms and constructing distribution lines.
关键词： Quantitative Forecasting,Photovoltaic Generator,Renewable energy,Levelized Cost of Electricity (LCOE) generation model
更新于2025-09-09 09:28:46
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Light-dressed states under intense optical near fields
摘要： We studied the excitation dynamics of a finite quantum system with an intense optical near field (ONF) from a perspective of light-dressed states. A simple model consisting of a single electron and a nanosized short dipole source were employed. By calculating the time-dependent wave function subjected to the ONF, we demonstrated that the optical responses involved not only the first- and third-order but also the second- and fourth-order harmonic generations that were not obtained from conventional spatially homogeneous laser fields. In order to elucidate the origins of the exotic even-order harmonic generations, the dressed states altered by the ONF were explored. The result showed that the spatial distribution of the dressed states were significantly influenced by the ONF, making forbidden optical transitions allowed by parity breaking. This was caused by the spatial inhomogeneousness of the ONF, specifically its asymmetry, that was inherited to the dressed states.
关键词： harmonic generation,parity breaking,light-dressed states,quantum system,optical near field
更新于2025-09-09 09:28:46
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Solar Generation, Storage, and Electric Vehicles in Power Grids: Challenges and Solutions with Coordinated Control at the Residential Level
摘要： Solar energy is an abundant renewable energy source that is available all around the world every day. each hour, the solar rays that reach our earth (if properly converted to electricity and other forms of energy) represent more than the total energy consumption of the entire human race over the course of one year. wind energy is another important renewable resource available in large amounts every day. these two renewable energy sources are attracting significant investment as countries seek technology cost reductions to aid sustainability. improvements in the conversion and use of larger fractions of solar and wind energy would help in terms of supply security and satisfying societal energy needs for decades and even centuries to come without adding high levels of carbon dioxide and other greenhouse gases to the environment. therefore, in several energy markets (such as in brazil, norway, germany, england, and australia), governments and regulators are emphasizing the need to increase the deployment of solar and wind energy sources as well as other measures to enhance monitoring, pricing, and control mechanisms in modern power grids.
关键词： Power Grids,Solar Generation,Electric Vehicles,Storage,Coordinated Control
更新于2025-09-09 09:28:46
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Fully-Integrated Charge Pump Design Optimization for Above-Breakdown Biasing of Single-Photon Avalanche Diodes in 0.13-μm CMOS
摘要： A design methodology for an area-optimized integrated charge pump is described suitable for on-chip high-voltage reverse bias of single-photon avalanche diodes (SPADs). The high-voltage generation block is implemented in a general-purpose 0.13-μm CMOS process and is capable of generating a maximum regulated output voltage of 17.7 V from an input of 1.8 V. An ON–OFF regulation scheme with dynamic charging and discharging capability of the charge pump provides fast recovery of the output bias voltage during SPAD transients, where overshoot and undershoot must both be corrected during active quench and reset. Following a SPAD avalanche current pulse, the measured transient recovery time is 500 ns from a 150-mV overshoot and a 500-mV undershoot to reach 99% of steady-state output. The implemented SPAD bias generation system occupies 0.175-mm2 chip area, without requiring an off-chip load capacitor.
关键词： Single-photon avalanche diode,charge pump,high-voltage generation,SPAD
更新于2025-09-09 09:28:46
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Second Harmonic Generation Imaging Analysis of Collagen Arrangement in Human Cornea
摘要： PURPOSE. To describe the horizontal arrangement of human corneal collagen bundles by using second harmonic generation (SHG) imaging. METHODS. Human corneas were imaged with an inverted two photon excitation ?uorescence microscope. The excitation laser (Ti:Sapphire) was tuned to 850 nm. Backscatter signals of SHG were collected through a 425/30-nm bandpass emission ?lter. Multiple, consecutive, and overlapping image stacks (z-stacks) were acquired to generate three dimensional data sets. ImageJ software was used to analyze the arrangement pattern (irregularity) of collagen bundles at each image plane. RESULTS. Collagen bundles in the corneal lamellae demonstrated a complex layout merging and splitting within a single lamellar plane. The patterns were signi?cantly different in the super?cial and limbal cornea when compared with deep and central regions. Collagen bundles were smaller in the super?cial layer and larger in deep lamellae. CONCLUSIONS. By using SHG imaging, the horizontal arrangement of corneal collagen bundles was elucidated at different depths and focal regions of the human cornea.
关键词： collagen,corneal stroma,second harmonic generation,cornea
更新于2025-09-09 09:28:46