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- 实验方案
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Self-Powered Filterless Narrow-Band pa??n Heterojunction Photodetector for Low Background Limited Near-Infrared Image Sensor Application
摘要： Photonic detection with narrow spectrum selectivity is very important to eliminate the signal from obtrusive light, which can improve the anti-interference ability of the infrared imaging system. While self-driving effect inherent to p-n junction is very attractive in optic-electronic integration, the application of p-n junction in narrow-band photodetector is limited by the usual broad absorption range. In this work, a self-powered filterless narrowband near-infrared photodetector based on CuGaTe2/silicon p-n junction was reported. The as-fabricated photodetector exhibited typical narrow-band response which shall be ascribed to the slightly smaller bandgap of Si than CuGaTe2 and the restricted photocurrent generation region in the p-n heterojunction by optimizing CuGaTe2 thickness. It is observed that when the thickness of CuGaTe2 film is 143 nm, the device exhibits a response peak centered around 1050 nm with a full-width at half-maximum of ~118 nm. Further device analysis reveals a specific detectivity of ~1012 Jones and a responsivity of 114 mA/W under 1064 nm illumination at zero bias. It was also found that image system based on the narrowband CuGaTe2/Si photodetector showed high noise immunity for its spectral selective characteristics.
关键词： p-n heterojunction,near infrared light,image sensing,spectral selectivity,narrow band photodetector
更新于2025-09-23 15:19:57
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - High Phosphorus-doped Seed Layer in Microcrystalline Silicon Oxide Front Contact Layers for Silicon Heterojunction Solar Cells
摘要： We report a 3-D-stackable 1S1R passive cross-point resistive random access memory (RRAM). The sneak (leakage) current challenge in the cross-point RRAM integration has been overcome utilizing a field-assisted superlinear threshold selector. The selector offers high selectivity of >107, sharp switching slope of <5 mV/decade, ability to tune the threshold voltage, stable operation at 125 °C, and endurance of >1011. Furthermore, we demonstrate 1S1R integration in which the selector-subthreshold current is <10 pA while offering >102 memory ON/OFF ratio and >106 selectivity during cycling. Combined with self-current-controlled RRAM, the 1S1R enables high-density and high-performance memory applications.
关键词： sneak path,cross-point memory,select device,resistive random access memory (RRAM),1S1R,selectivity
更新于2025-09-23 15:19:57
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[IEEE 2019 International Conference on Microwave and Millimeter Wave Technology (ICMMT) - Guangzhou, China (2019.5.19-2019.5.22)] 2019 International Conference on Microwave and Millimeter Wave Technology (ICMMT) - A Waveguide Bandpass Filter with High Selectivity Using Slot Excitation
摘要： Under the excitation of a pair of shifted inclined slots, TE101, TE011 and TM110 modes in a single rectangular cavity are excited, and exploited to form a passband of bandpass filter (BPF). The pair of slots are fed through microstrip lines at the input and output port. Based on the single triple-mode rectangular cavity, a dual-cavity BPF is designed, fabricated and measured to enhance the selectivity of filter by cascading two single ones. The BPF could achieve about 32 MHz bandwidth at center frequency of 2.98 GHz, and two transmission zeros (TZs) at 2.925 and 3.005 GHz, leading to the suppression outside passband larger than 50 dB in the vicinity of center frequency.
关键词： Waveguide,Slot Excitation,High Selectivity,Bandpass Filter
更新于2025-09-23 15:19:57
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<scp>Coupleda??line</scp> banda??pass filter with <scp>Ta??shaped</scp> structure for high frequency selectivity and stopband rejection
摘要： A coupled-line band-pass filter (BPF) with T-shaped stub structure is presented. Five transmission poles within the passband and eight deep transmission zeros (TZs) from 0 to 2f0 (f0 denotes filter's center frequency) are realized through input impedance calculations. With the simple T-shaped structure, the positions of six TZs can be appropriately adjusted to achieve high frequency selectivity and stopband rejection. For demonstration, a BPF prototype centered at 2.05 GHz is designed and fabricated, whose measured rejection levels are of over 45.5 dB at lower stopband and better than 19.5 dB at upper stopband. The simulation and measurement results are in good agreement, which validates the design idea.
关键词： high selectivity,band-pass filter,T-shaped structure,stopband rejection,coupled-line
更新于2025-09-23 15:19:57
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Regio- and stereo-selective [4+4] photodimerization of angular-shaped dialkyltetracenedithiophene
摘要： Angular-shaped dialkyltetracenedithiophenes (aTDTs) undergo [4+4] photodimerization in solution to form a butterfly-shaped skeleton. This reaction proceeds in a regio- and stereo-selective manner, forming only a single planosymmetric syn-[2,2]-daTDT out of six possible products. The photocycloaddition of aTDTs can take place topochemically in the thin-film state while maintaining regio- and stereo-selectivity. Stronger aliphatic dispersion forces and π–π interactions play important roles in forming the eclipsed dimeric complex that leads to the syn-[2,2]-daTDT isomer.
关键词： regio-selectivity,tetracenedithiophene,stereo-selectivity,topochemical reaction,photodimerization
更新于2025-09-19 17:15:36
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Morphological effect of titanate nanostructures on the photocatalytic degradation of crystal violet
摘要： The heterogeneous photocatalysis using semiconductor nanocrystals is an important process in the field of water treatment since it is a low cost, environmentally friendly, and zero waste technique. In this work, titanate nanostructures (sheets, tubes, and wires) were prepared by simple hydrothermal method. All samples were characterized by X-ray diffraction, transmission electron microscopy, Brunauer–Emmett–Teller surface area analysis, and Zetasizer. The results revealed that tuning the morphology of TiO2 changed the activity of the prepared nanostructures, where titanate nanowires exhibited the highest photocatalytic activity toward crystal violet dye, reaching 100% at pH 3 under ultraviolet illumination for 35 min.
关键词： water-treatment,crystal violet,selectivity,Selective degradation,titanate,photocatalysis
更新于2025-09-19 17:15:36
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Selectivity, Thermodynamic and Anisotropic Properties of Substituted Liquid-Crystal Cyanoazoxybenzenes as Stationary Phases for Gas Chromatography
摘要： Herein we discuss physical properties of 4-(ω-hydroxyalkoxy)-4’-cyanoazoxybenzene homologs. 1D and 2D correlation NMR spectroscopy (in particular, 1Н, 15N-HMBC experiment) have allowed elucidation of structure of the prepared rod-like supramolecular cyanoazoxybenzenes. Mesomorphic properties of the compounds have been studied by means of polarization thermomicroscopy and differential scanning calorimetry. All the studied cyanoazoxybenzenes have revealed enantiotropic nematic mesomorphism over wide temperature range. Nematic mesophase of the eighth homolog has possessed large positive dielectric anisotropy. Introduction of small amounts of the prepared cyanoazoxybenzenes as additive has stabilized the mesophase and has increased the dielectric anisotropy of 4-pentyloxy-4’-cyanobiphenyl. Gas-liquid chromatography studies have shown that sorbents based on 4-(2-hydroxyethyloxy)-4’-cyanoazoxybenzene are highly selective towards various structural isomers; that cannot be achieved using conventional nematic liquid crystals. Thermodynamic evidence of specific interactions between the mesogen and the non-mesomorphic sorbate has been discovered.
关键词： Mesogen,Dielectric anisotropy,Sorbent,Hydrogen bond,Structural selectivity,NMR spectroscopy,Nematic phase,Position isomerism,Azoxybenzene,Double refraction,Supramolecule
更新于2025-09-19 17:15:36
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[BestMasters] Topographic Organization of the Pectine Neuropils in Scorpions (An Analysis of Chemosensory Afferents and the Projection Pattern in the Central Nervous System) || High Performance VOCs Sensor Based on ?-Fe2O3/Al-ZnO Nanocomposites
摘要： In this study, ternary G-Fe2O3/Al-ZnO nanocomposites (NC) were prepared using the solvothermal sol-gel process and a successive supercritical drying in ethanol. SEM analysis of the ternary NC samples showed clearly that they are formed by very small nanoparticles in the nanometer range. XRD highlighted the presence of the characteristic diffraction peaks of G-Fe2O3 and ZnO phases in all samples. Conductometric sensors were fabricated and tested for the monitoring of acetone in air. Results obtained have demonstrated that the ternary composite-based sensors display higher response to acetone and ethanol compared to that obtained with Al-ZnO and G-Fe2O3 ones.
关键词： Sol-gel,Acetone Selectivity,G-Fe2O3,Al-ZnO,Composite nanoparticles
更新于2025-09-19 17:15:36
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Plasmonic photocatalysis applied to solar fuels
摘要： The induction of chemical processes by plasmonic systems is a rapidly growing field with potentially many strategic applications. One of them is the transformation of solar energy into chemical fuel by the association of plasmonic metal nanoparticles (M NPs) and a semi-conductor (SC). When the localized surface plasmon resonance (LSPR) and the SC absorption do not match, one limitation of these systems is the efficiency of hot electron transfer from M NPs to SC through the Schottky barrier formed at the M NPs/SC interfaces. Here we show that high surface area 1wt.%Au/TiO2-UV100, prepared by adsorption of a NaBH4-protected 3 nm gold sol, readily catalyzes the photoreduction of carbon dioxide with water into methane under both solar and visible-only irradiations with a CH4 vs. H2 selectivity of 63%. Tuning Au NPs size and titania surface area, in particular via thermal treatments, highlights the key role of the metal dispersion and of the accessible Au-TiO2 perimeter interface on the direct SC-based solar process. The impact of Au NPs density in turn evidences the dual role of gold as co-catalyst and recombination sites for charge carriers. It is shown that the plasmon-induced process contributes up to 20% of the solar activity. The plasmon-based contribution is enhanced by a large Au NP size and a high degree of crystallinity of the SC support. By minimizing surface hydroxylation while retaining a relatively high surface area of 120 m2 g-1, pre-calcining TiO2-UV100 at 450°C leads to an optimum monometallic system in terms of activity and selectivity under both solar and visible irradiation. A state-of-the-art methane selectivity of 100% is achieved in the hot electron process.
关键词： Methane production,Gold nanoparticles,Titania,Selectivity,CO2 reduction,Hot electrons,Plasmonic photocatalysis,Solar fuels
更新于2025-09-19 17:15:36
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Identification, Characterization, and Optimization of Integrin αvβ6-Targeting Peptides from a One-Bead One-Compound (OBOC) Library: Towards the Development of Positron Emission Tomography (PET) Imaging Agents
摘要： The current translation of peptides identified through the one-bead one-compound (OBOC) technology into positron emission tomography (PET) imaging agents is a slow process, with a major delay between ligand identification and subsequent lead optimization. This work aims to streamline the development process of 18F-peptide based PET imaging agents to target the integrin αvβ6. By directly identify αvβ6–targeting peptides from a 9-mer 4-fluorobenzoyl peptide library using the on-bead two-color (OBTC) cell-screening assay, a total of 185 peptide beads were identified and 5 beads sequenced for further evaluation. The lead peptide 1 (VGDLTYLKK(FB), IC50 = 0.45 ± 0.06 μM, 25% stable in serum at 1 h) was further modified at the N-, C-, and bi-termini. C-terminal PEGylation increased the metabolic stability (>95% stable), but decreased binding affinity (IC50 = 3.7 ± 1 μM) was noted. C-terminal extension (1i, VGDLTYLKK(FB)KVART) significantly increased binding affinity for integrin αvβ6 (IC50 = 0.021 ± 0.002 μM), binding selectivity for αvβ6-expressing cells (3.1 ± 0.8:1), and the serum stability (>99% stable). Our results demonstrate the challenges in optimizing OBOC-derived peptides, indicate both termini of 1 are sensitive to modifications, and show that further modification of 1 is necessary to demonstrate utility as an 18F-peptide imaging agent.
关键词： Fluorine-18,integrin αvβ6,affinity,one-bead one-compound (OBOC),library screening,solid-phase radiolabeling,positron emission tomography (PET),selectivity
更新于2025-09-19 17:15:36