- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Mechanistic Origin of the High Performance of Yolk@Shell Bi2S3@N-Doped Carbon Nanowire Electrodes
摘要： High-performance lithium-ion batteries are commonly built with the heterogeneous composite electrodes that combine multiple active components for serving various electrochemical and structural functions. Engineering these heterogeneous composite electrodes toward drastically improved battery performance is hinged on a fundamental understanding of the mechanisms of multiple active components and their synergy or tradeoff effects. Herein, we report a rational design, fabrication, and understanding of yolk@shell Bi2S3@N-doped mesoporous carbon (C) composite anode, consisting of a Bi2S3 nanowire (NW) core within a hollow space surrounded by a thin shell of N-doped mesoporous C. This composite anode exhibits desirable rate performance and long cycle stability (700 cycles, 501 mAhg-1 at 1.0 Ag-1, 85% capacity retention). By in-situ transmission electron microscopy (TEM), X-ray diffraction, and NMR experiments and computational modeling, we elucidate the dominant mechanisms of the phase transformation, structural evolution, and lithiation kinetics of the Bi2S3@C NW anode. Our combined in-situ TEM experiments and finite-element simulations reveal that the hollow space between the Bi2S3-NW core and carbon shell can effectively accommodate the lithiation-induced expansion of Bi2S3-NWs without cracking C shells. This work demonstrates an effective strategy of engineering the yolk@shell-architectured anodes and also sheds light onto harnessing the complex multistep reactions in metal sulfides to enable high-performance lithium-ion batteries.
关键词： multiple computational modeling,lithiation mechanism,in-situ experiments,yolk@shell composite anode,lithium-ion battery
更新于2025-09-23 15:21:01
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An Efficient Non-Invasive Method to Fabricate In-Fiber Microcavities Using a Continuous-Wave Laser
摘要： Natural ecosystems exhibit complex dynamics of interacting species. Man-made ecosystems exhibit similar dynamics and, in the case of mobile app stores, can be said to perform optimization as developers seek to maximize app downloads. This work aims to understand stability and instability within app store dynamics and how it affects ?tness. The investigation is carried out with AppEco, a model of the iOS App Store, which was extended for this paper and updated to model the store from 2008 to 2014. AppEco models apps containing features, developers who build the apps, users who download apps according to their preferences, and an app store that presents apps to the users. It also models developers who use commonly observed strategies to build their apps: innovator, milker, optimizer, copycat, and ?exible (the ability to choose any strategy). Results show that despite the success of the copycat strategy, there is a clear stable state for low proportion of copycats in developer populations, mirroring results in theoretical biology for producer–scrounger systems. The results also show that the best ?tness is achieved when the evolutionary optimizer (as producer) and copycat (as scrounger) strategies coexist together in stable proportions.
关键词： mobile app developers,Agent-based simulation,evolutionary ecosystem model,genetic algorithms,app stores,producer–scrounger systems,computational modeling
更新于2025-09-23 15:19:57
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High-Performance Synthesis of Phosphorus-Doped Graphene Materials and Stabilization of Phosphoric Micro- and Nanodroplets
摘要： A thermally induced cascade process leading to the formation of stable micro- and nanometer-size phosphoric droplets was developed starting from a molecular precursor. Microwave-induced pyrolysis of 1,2,3,4,5-pentaphenylphosphole oxide proceeded through a series of subsequent transformations involving formation of phosphorus-doped graphene oxide layers, seeding of carbon surface with phosphorus centers, and assembling of stable droplets. A complex nanostructured organization of the material was established in a remarkably short time of 3 min, and the process was performed in a thermally induced manner using microwave irradiation. High stability of the liquid phosphoric structures on the surface of doped graphene oxide over a few-month period was demonstrated, as well as under challenging conditions in organic solvents (chloroform, methylene chloride, or toluene media) and even under sonication. Detailed examination of this material by electron microscopy and a number of analytical methods showed its unique organization at the nanoscale, whereas computational modeling revealed unusually strong binding of phosphorus oxide P4O10 to the graphene surface. The study demonstrates a fascinating opportunity to access a complex nanostructured multicomponent material from a single and easily available molecular precursor.
关键词： microwave-induced pyrolysis,phosphorus-doped graphene,computational modeling,phosphoric droplets,nanostructured materials
更新于2025-09-23 15:19:57
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[IEEE 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Huangshan, China (2019.8.5-2019.8.8)] 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Research on real-time BER estimation in satellite downlink
摘要： Natural ecosystems exhibit complex dynamics of interacting species. Man-made ecosystems exhibit similar dynamics and, in the case of mobile app stores, can be said to perform optimization as developers seek to maximize app downloads. This work aims to understand stability and instability within app store dynamics and how it affects ?tness. The investigation is carried out with AppEco, a model of the iOS App Store, which was extended for this paper and updated to model the store from 2008 to 2014. AppEco models apps containing features, developers who build the apps, users who download apps according to their preferences, and an app store that presents apps to the users. It also models developers who use commonly observed strategies to build their apps: innovator, milker, optimizer, copycat, and ?exible (the ability to choose any strategy). Results show that despite the success of the copycat strategy, there is a clear stable state for low proportion of copycats in developer populations, mirroring results in theoretical biology for producer–scrounger systems. The results also show that the best ?tness is achieved when the evolutionary optimizer (as producer) and copycat (as scrounger) strategies coexist together in stable proportions.
关键词： producer–scrounger systems,computational modeling,app stores,evolutionary ecosystem model,mobile developers,genetic algorithms,Agent-based simulation
更新于2025-09-19 17:13:59
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Computational modeling of ultraviolet light-emitting diode (UV-LED) reactor for water treatment
摘要： The ultraviolet light emitting diode (UV-LED) has recently emerged as a new UV source. It offers design flexibility due to its small size and ability to alter its radiation profile. In view of the variety of design possibilities for a UV-LED reactor, a computational model could be of great value for simulating the reactor and providing insight into its performance. Given the UV-LED's ability to emit various radiation wavelengths and because it is a directional UV source, the challenges of simulation for UV-LEDs are greater than those for UV lamps, which typically have a single wavelength and an almost radial radiation profile. This study proposes a method of simulating UV-LED reactors in the Eulerian framework through the integration of the kinetic, hydrodynamic, and radiation models, representing UV-LED systems. Additionally, the concept of an ideal UV-LED system is proposed, which can provide insight into the efficiency of any UV-LED reactor design concept. The integrated model of reactor performance is evaluated through experimental studies of challenge organisms (e.g., Escherichia coli and MS2) in two UV-LED reactors under different operating conditions, including flow rates, flow regimes, radiant powers, and UV-LED configurations. The close agreement between the numerical predictions and experimental data demonstrates the ability of the proposed method to simulate UV-LED reactor performance.
关键词： Computational modeling,Ideal UV-LED reactor,UV-LED reactor performance,Design efficiency,UV-LED
更新于2025-09-19 17:13:59
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[IEEE 2019 Workshop on Recent Advances in Photonics (WRAP) - Guwahati, India (2019.12.13-2019.12.14)] 2019 Workshop on Recent Advances in Photonics (WRAP) - Experimental Verification of Enhanced Photoluminescence in p-doped GaAs using Fluorescence Lifetime Measurements
摘要： Recent studies indicate that pretreating microorganisms with ribosome-targeting antibiotics may promote a transition in the microbial phenotype, such as the formation of persister cells; i.e., those cells that survive antibiotic treatment by becoming metabolically dormant. In this letter, we developed the first genome-scale modeling approach to systematically investigate the influence of ribosome-targeting antibiotics on the metabolism of Pseudomonas aeruginosa. An approach for integrating gene expression data with metabolic networks was first developed to identify the metabolic reactions whose fluxes were positively correlated with gene activation levels. The fluxes of these reactions were further constrained via a flux balance analysis to mimic the inhibition of antibiotics on microbial metabolism. It was found that some of metabolic reactions with large flux change, including metabolic reactions for homoserine metabolism, the production of 2-heptyl-4-quinolone, and isocitrate lyase, were confirmed by existing experimental data for their important role in promoting persister cell formation. Metabolites with large exchange-rate change, such as acetate, agmatine, and oxoglutarate, were found important for persister cell formation in previous experiments. The predicted results on the flux change triggered by ribosome-targeting antibiotics can be used to generate hypotheses for future experimental design to combat antibiotic-resistant pathogens.
关键词： persister cells,systems biology,flux balance analysis (FBA),Computational modeling and simulations in biology
更新于2025-09-19 17:13:59
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[Laser Institute of America ILSC? 2019: Proceedings of the International Laser Safety Conference - South Kissimmee, Florida, USA (March 18–21, 2019)] International Laser Safety Conference - Visible lesion threshold modeling of skin laser exposure at 1070-nm
摘要： Computational models are capable of quantifying the expected thermal response of biological tissue to laser irradiation. A typical laser-tissue model accounts for optical energy deposition, heat transfer, and damage assessment, with calculation of the Arrhenius integral. Previous studies have successfully employed these methods to predict skin damage thresholds at laser wavelengths with high absorption in water, and usually for single continuous-wave exposures. However, there remains a need for a robust and accurate predictive model in low-absorption, high-scattering cases, such as for lasers in the near-infrared (NIR) region near 1 μm, where a large volume of tissue is heated simultaneously. This study presents a framework for modeling laser irradiation of skin tissue at 1070-nm for both continuous-wave and pulsed exposures with durations ranging from 10-2 to 101 seconds. We report the modeled skin thermal responses alongside thermal camera recordings of in-vivo porcine exposures as validation of simulation integrity. Comparisons of modeled damage thresholds calculated by the Arrhenius integral with past experimentally-determined minimum visible lesion ED50 data demonstrate a high degree of accuracy. The techniques outlined by this study provide a useful tool in assessing potentially hazardous near-infrared laser exposure scenarios while informing future investigations into modeling skin laser exposure at these wavelength regions.
关键词： near-infrared,Arrhenius integral,laser-tissue interaction,skin damage thresholds,computational modeling
更新于2025-09-16 10:30:52
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[IEEE 2019 Compound Semiconductor Week (CSW) - Nara, Japan (2019.5.19-2019.5.23)] 2019 Compound Semiconductor Week (CSW) - GaN-based Inverter by Monolithic Integration of Threshold Controlled MOSFETs
摘要： Natural ecosystems exhibit complex dynamics of interacting species. Man-made ecosystems exhibit similar dynamics and, in the case of mobile app stores, can be said to perform optimization as developers seek to maximize app downloads. This work aims to understand stability and instability within app store dynamics and how it affects ?tness. The investigation is carried out with AppEco, a model of the iOS App Store, which was extended for this paper and updated to model the store from 2008 to 2014. AppEco models apps containing features, developers who build the apps, users who download apps according to their preferences, and an app store that presents apps to the users. It also models developers who use commonly observed strategies to build their apps: innovator, milker, optimizer, copycat, and ?exible (the ability to choose any strategy). Results show that despite the success of the copycat strategy, there is a clear stable state for low proportion of copycats in developer populations, mirroring results in theoretical biology for producer–scrounger systems. The results also show that the best ?tness is achieved when the evolutionary optimizer (as producer) and copycat (as scrounger) strategies coexist together in stable proportions.
关键词： Agent-based simulation,genetic algorithms,mobile developers,app systems,evolutionary ecosystem model,computational modeling,app stores
更新于2025-09-16 10:30:52
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Computer Simulation and Investigations of the Roof Mount Photovoltaic System
摘要： The interest in the renewable energy sources is increasing due to the depletion of the conventional energy sources and the environmental pollution. In this paper we present a computer simulation and investigations of the roof mounted photovoltaic system. The results of the generated power of the 5kW built-in photovoltaic system by months over a period of 5 years are presented. Depending on the meteorological conditions, the investigated photovoltaic system generates year-round energy necessary for the needs of the household.
关键词： computer simulation inverters,photovoltaic systems,Computational modeling
更新于2025-09-12 10:27:22
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[IEEE 2018 EMF-Med 1st World Conference on Biomedical Applications of Electromagnetic Fields (EMF-Med) - Split, Croatia (2018.9.10-2018.9.13)] 2018 EMF-Med 1st World Conference on Biomedical Applications of Electromagnetic Fields (EMF-Med) - Comparison between Direct Electrical and Optogenetic Subthalamic Nucleus Stimulation
摘要： Subthalamic nucleus deep brain stimulation is a treatment for Parkinson’s disease. In this study, a computational model of a plateau-potential generating subthalamic nucleus neuron (Otsuka-model) and a four-state ChR2(H134R) model (Williams-model) are combined, in order to compare electrical and optogenetic neuromodulation capabilities. The impact of the stimulation modality (optogenetic or electric) on firing rates, strength-duration curves and action potential shape is investigated. First, in contrast to electrical stimulation, mean instantaneous firing rates saturate for optical stimulation at intensities higher than 0.1 W/cm2. Second, rheobase and chronaxie are 175% and 9.6% larger in optogenetic stimulation compared to electrical stimulation, respectively. Third, action potential shape is not significantly impacted by the neurostimulation modality.
关键词： Optogenetics,Channelrhodopsin-2 (H134R),subthalamic nucleus,Otsuka-model,computational modeling
更新于2025-09-10 09:29:36