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- 实验方案
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Triplet-State Photochemistry of Dissolved Organic Matter: Triplet-State Energy Distribution and Surface Electric Charge Conditions
摘要： Excited triplet states of chromophoric dissolved organic matter (3CDOM*) are highly reactive species in sunlit surface waters and play a critical role in reactive oxygen species (ROS) formation and pollutant attenuation. In the present study, a series of chemical probes, including sorbic acid, sorbic alcohol, sorbic amine, trimethylphenol, and furfuryl alcohol, were employed to quantitatively determine 3CDOM* and 1O2 in various organic matters. Using a high concentration of sorbic alcohol as high-energy triplet states quencher, 3CDOM* can be first distinguished as high-energy triplet states (>250 kJ mol?1) and low-energy triplet states (<250 kJ mol?1). The terrestrial-origin natural organic matter (NOM) was found to mainly consist of low-energy triplet states, while high-energy triplet states were predominant in autochthonous-origin NOM and effluent/wastewater organic matter (EfOM/WWOM). The 1O2 quantum yields and electron transfer quantum yield coefficients (f TMP) generated from low-energy triplet states remained constant in all tested organic matters. External phenolic compound showed quenching effects on triplet-state formation and tended to have a higher quenching efficiency for aromatic ketone triplet states, which are the main high-energy triplet states. In comparison with terrestrial-origin NOM, autochthonous-origin NOM and EfOM/WWOM presented lower reaction rate constants for sorbic amines and higher reaction rate constants for sorbic acid, and these differences are likely due to dissimilar surface electric charge conditions. Understanding the triplet-state photochemistry of CDOM is essential for providing useful insights into their photochemical effects in aquatic systems.
关键词： surface charge,triplet-state photochemistry,energy distribution,dissolved organic matter,reactive oxygen species,chemical probes
更新于2025-11-19 16:56:35
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[IEEE 2018 31st International Vacuum Nanoelectronics Conference (IVNC) - Kyoto, Japan (2018.7.9-2018.7.13)] 2018 31st International Vacuum Nanoelectronics Conference (IVNC) - Field emission from vertically-aligned graphene edges on graphitized pencil lead
摘要： We have already demonstrated that the graphitized mechanical pencil lead show superior field emission features in high emission current regime [1]. In this paper, we present the results of additional detailed analysis of field emission from completely graphitized pencil lead including Raman scattering, FIM/FEM images and energy distributions of emitted electrons as well as field emission characteristics also in low emission current regime. It is concluded again that the fully graphitized pencil lead is promising as low cost but superior field emitters
关键词： graphite,energy distribution,FIM,FEM,vertically-aligned graphene,field emission
更新于2025-09-23 15:21:21
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[IEEE 2018 31st International Vacuum Nanoelectronics Conference (IVNC) - Kyoto, Japan (2018.7.9-2018.7.13)] 2018 31st International Vacuum Nanoelectronics Conference (IVNC) - Field Emission Energy Distribution from Planar Integrated Graphene
摘要： We report field emission energy distributions from planar graphene edges. Field effect transistors with integrated gate and drain electrodes and vacuum transport parallel to the substrate surface are fabricated using graphene edge emission sources are prepared from two types of graphene. The emission distributions produced by reduced graphene oxide are roughly symmetric, often time. These contain multiple peaks, and shift over characteristics suggest the emission originates in local edge states. Emission produced by high quality graphene grown on Cu foil more closely resembles emission from a linear density of states, suggesting the emission starts from the delocalized band as well as discrete states.
关键词： energy distribution,graphene edge,vacuum transistor,Field emission
更新于2025-09-23 15:21:21
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Deviations from generalized equipartition in confined, laser-cooled atoms
摘要： We observe a signi?cant steady-state deviation from the generalized equipartition theorem, one of the pivotal results of classical statistical mechanics, in a system of con?ned, laser-cooled atoms. We parametrize this deviation, measure its dynamics, and show that its steady-state value quanti?es the departure of nonthermal states from thermal equilibrium even for anharmonic con?nement. In particular, we ?nd that deviations from equipartition grow as the system dynamics becomes more anomalous. We present numerical simulations that validate the experimental data and reveal an inhomogeneous distribution of the kinetic energy through the system, supported by an analytical examination of the phase space.
关键词： kinetic energy distribution,laser-cooled atoms,generalized equipartition theorem,anharmonic con?nement,nonthermal states
更新于2025-09-23 15:19:57
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[IEEE 2019 6th International Conference on Advanced Control Circuits and Systems (ACCS) & 2019 5th International Conference on New Paradigms in Electronics & information Technology (PEIT) - Hurgada, Egypt (2019.11.17-2019.11.20)] 2019 6th International Conference on Advanced Control Circuits and Systems (ACCS) & 2019 5th International Conference on New Paradigms in Electronics & information Technology (PEIT) - Photovoltaic-Based Interconnected-Modified DC-Nanogrids within an Open Energy Distribution System
摘要： A DC nano-grid is typically intended as a reliable scheme capable of delivering power to the local loads from distributed renewable energy resources. The conventional nano-grid uses two-separate conversion stages for feeding both ac and dc loads. But, the modified design for the dc nano-grid uses only a single-stage converter. It is based on a single-input power-electronic multi-output converter that interfaces the source with the average load requirements. It deals with a switched boost inverter (SBI) that can fed from a solar photovoltaic (PV) renewable energy source. SBI is a single-stage power converter capable of simultaneously supplying both dc and a higher or lower ac loads from a single dc input voltage source. The converter operation is also contributed by a simple model reference adaptive closed loop control technique, to fed the high output ratings steadily, especially in the critical range for its duty ratio. In addition, this paper presents a full model design for multiple interconnected nanogrids through a dc-link within a multilevel direct current (dc) scheme called an open energy distributed system (OEDS). Each nanogrid involves a switched boost inverter (SBI) providing its closed-loop control method for its dc-link voltage. Moreover, this paper involves a controller method to attain the optimum suggested power interconnected nanogrids. The proposed systems are modelled and simulated with the help of MATLAB/Simulink software package to assess the robustness of the proposed OEDS with multiple 5-Kw interconnected nanogrids fed from photovoltaic (PV) renewable energy resources.
关键词： Switched Boost Inverter (SBI),Modified - DC nanogrids,Distributed Renewable Energy Source (DRES),Open Energy Distribution System (OEDS)
更新于2025-09-19 17:13:59