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[Studies in Computational Intelligence] Advances in Neural Computation, Machine Learning, and Cognitive Research II Volume 799 (Selected Papers from the XX International Conference on Neuroinformatics, October 8-12, 2018, Moscow, Russia) || Artificial Neural Networks for Diagnostics of Water-Ethanol Solutions by Raman Spectra
摘要： The present paper is devoted to an elaboration of a method of diagnosis of alcoholic beverages using artificial neural networks: the inverse problem of spectroscopy – determination of concentrations of ethanol, methanol, fusel oil, ethyl acetate in water-ethanol solutions – was solved using Raman spectra. We obtained the following accuracies of concentration determination: 0.25% vol. for ethanol, 0.19% vol. for fusel oil, 0.35% vol. for methanol, and 0.29% vol. for ethyl acetate. The obtained results demonstrate the prospects of using Raman spectroscopy in combination with modern data processing methods (artificial neural networks) for the elaboration of an express non-contact method of detection of harmful and dangerous impurities in alcoholic beverages, as well as for the detection of counterfeit and low-quality beverages.
关键词： Neural networks,Raman spectroscopy,Inverse problems,Water-ethanol solutions
更新于2025-09-10 09:29:36
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Potentiality of zinc oxide nanosensor prepared by a new electroplating method on p-Si (1?1?1) wafer substrate
摘要： Nanostructured ZnO thin films were deposited on p-Si (1 1 1) substrates using a new electrodeposition method. Electrical and sensing properties were investigated. Variations of the resistance measured between two points of the ZnO film, have shown a maximum sensitivity (d = 10) in the presence of gas ?CO? and (d = 14,70) in the presence of ?C2H5OH? at a temperature of 300 (cid:1)C. Therefore, we can say that the sensitivity tests indicate that the sensor consisting of a nanometer zinc oxide layer is more efficient at temperatures beyond 100 (cid:1)C. Moreover, the sensing element has demonstrated a good response to reducing gases species.
关键词： Sensitivity,ZnO,Ethanol/carbon monoxide sensor,Electrodeposition,Response/recovery times
更新于2025-09-10 09:29:36
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Wet-chemical preparation of TiO2-nanostructures using different solvents: Effect of CTAB concentration and tentative mechanism of particle formation
摘要： In this paper, TiO2 nanostructures (TiO2-NSs) were synthesized in a controlled way. The effects of the use of a surfactant, Cetyl trimethylammonium bromide (CTAB), and the nature of the solvent of synthesis (ethanol and toluene) on the characteristics of the final product were studied. For this, TiO2-NSs were characterized using IR spectroscopy, X-ray diffraction (XRD), Transmission and Scanning Electron Microscopy. The solid obtained, without heat treatment, presented an amorphous structure that crystallized when treated at 450 °C, giving anatase as crystalline phase, independent of the solvent of synthesis and the concentration of CTAB used. The size of the crystallite in the powders synthesized was 3-5 nm and was reduced on increasing CTAB concentration, regardless of the solvent used. Using ethanol, the primary particles had a spheroidal or needle type shape of nanometric size (<100 nm) and the agglomerates were spherical (1 to 5 μm), reducing in size on the addition of CTAB. On using toluene, irregular-shaped aggregates with acute edges were formed (10 to 20 μm), made up of primary particles nanometric (<100 nm) and with the presence of poros. Given the nature of the synthesis process, a mechanism was proposed to explain the formation of the TiO2-NSs.
关键词： toluene,mechanism of formation,ethanol,TiO2 nanostructures,synthesis,surfactant
更新于2025-09-10 09:29:36
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Tailoring the surface structure of silicon carbide support for copper catalyzed ethanol dehydrogenation
摘要： The production of acetaldehyde through biomass-derived ethanol dehydrogenation is a sustainable alternative compared to the fossil-feedstock based process, for which Cu-based catalysts are considered to be the most efficient. Herein, we modified the surface of silicon carbide (SiC) to alter the properties of the interface from SiO2-rich to C-rich, and we prepared a series of Cu-supported catalysts (Cu/SiC, Cu/SiO2/SiC, and Cu/C/SiC) with the aim of insight into the effect of the interface structure and composition on catalytic dehydrogenation of ethanol. At 280 °C, the Cu/SiO2/SiC catalyst exhibits high ethanol conversion due to the excellent dispersion of Cu nanoparticles promoted by SiO2-rich interface. In contrast, Cu nanoparticles dispersed on C/SiC shows somewhat lower activity but excellent acetaldehyde selectivity with trace amounts of by-products under identical reaction conditions. This difference is attributed to the fast removal of acetaldehyde because of its low affinity for the relatively inert C-rich interface (C/SiC). This work provides an in-depth understanding of Cu-Si-C multi-interfacial structure and the ethanol dehydrogenation behavior, which may shed light on the design of novel catalysts with tailored interfacial structures.
关键词： dehydrogenation,ethanol,SiC,copper,surface structure
更新于2025-09-10 09:29:36
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Visible Light-Promoted Plasmon Resonance to Induce “Hot” Hole Transfer and Photothermal Conversion for Catalytic Oxidation
摘要： Titanium dioxide (TiO2) semiconductor photocatalysts were photosensitized to the visible spectrum with gold nanospheres (AuNSs) and gold nanorods (AuNRs) to study the ethanol photo-oxidation cycle, with an emphasis towards driving carbon-carbon (C-C) bond cleavage at low temperatures. The photocatalysts exhibited a localized surface plasmon resonance (SPR) that was harnessed to drive the complete photo-oxidation of formic acid (FA) and ethanol (EtOH) via augmented carrier generation/separation and photothermal conversion. Contributions of transverse and longitudinal localized SPR modes were decoupled by irradiating AuNSs-TiO2 and AuNRs-TiO2 with targeted wavelength ranges to probe their effects on plasmonically-assisted photocatalytic oxidation of FA and EtOH. Photocatalytic performance was assessed by monitoring the yield of gaseous products during photo-oxidation experiments using a gas chromatography-mass spectrometry-multiple headspace extraction (GC-MS-MHE) analysis method. The complete oxidation of EtOH to CO2 under visible-light irradiation was confirmed by GC-MS-MHE for both AuNSs and AuNRs on TiO2 at room temperature. Photothermal and local field enhancements were found to aid in selectively cleaving the C-C bond in EtOH to form FA, while FA was further oxidized to CO2 by plasmon-induced electron transfer mechanisms. Under visible light (>420 nm) irradiation, carrier generation/separation and photothermal conversion was achieved, resulting in the photogenerated “hot” holes driving the photo-oxidation primarily on the AuNPs. Specifically, plasmonic enhancement by AuNR-TiO2 enhances EtOH oxidation, providing a method to selectively cleave C-C bonds.
关键词： Carbon-carbon bond cleavage,Photocatalysis,Hybrid Materials,Gold nanoparticles,Ethanol oxidation,Magnetic,Formic acid oxidation,Plasmonics,TiO2,Optical
更新于2025-09-10 09:29:36
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Giant Chemical Surface Enhancement of Coherent Raman Scattering on MoS <sub/>2</sub>
摘要： Raman spectroscopy is a powerful tool for molecular chemical analysis and bio-imaging, which shows an astonishing sensitivity when combined with a huge enhancement by the coherence and surface effects. Noble metal nanoparticles have been commonly used for the spontaneous surface-enhanced Raman scattering (SERS) and for the surface-enhanced coherent anti-Stokes Raman scattering (SECARS) spectroscopies, as they provide large enhancement factors via the electromagnetic and chemical mechanisms. Recently, two-dimensional (2D) semiconductors, such as monolayer molybdenum disulfide (MoS2), were used for the potential SERS applications as cheaper substrates compared to the noble metal nanoparticles. However, the coherent enhancement of SECARS on 2D materials has not been previously explored. Here we present the experimental SECARS measurements of pyridine-ethanol solutions containing 2D MoS2 nanocrystals with the giant chemical enhancement factor of 109 over coherent anti-Stokes Raman scattering (CARS), which is attributed to the charge transfer states and resonant MoS2 excitation. As a comparison, the SERS signals on MoS2 using incoherent nonresonant excitation show at least two orders of magnitude smaller enhancement. Time-resolved SECARS measurements directly reveal the increased vibrational dephasing rates which provide strong evidence for the charge transfer in the pyridine-ethanol-MoS2 system.
关键词： pyridine,MoS2,SERS,Raman,ethanol,CARS,SECARS
更新于2025-09-10 09:29:36
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Large-scale synthesis of dual-emitting-based visualization sensing paper for humidity and ethanol detection
摘要： A novel visual and fluorometric-sensor paper is prepared for the monitoring of atmospheric humidity and ethanol. The paper contains a combination of copper nanoclusters (CuNCs) and carbon dots (CDs), immobilized on a filter paper. This makes it a dual-emission system. The visual sensor shows bright fluorescence and has a diameter of ～8 cm with uniform and homogeneous surface. The detection mechanism of the sensing paper is based on the fluorescence intensity variation of CuNCs in different environments. Desirable linear relationship is observed between fluorescence intensity ratio (red/blue) and humidity. Visible color transformation of this sensor paper is observed in the humidity range ～40-80%, implying utility for easy and facile atmospheric humidity determination. Furthermore, due to the water and ethanol have different impacts on the spectrum, this paper-based fluorescent probe shows excellent response to ethanol. Therefore dual-emitting sensing paper, when suitably calibrated, shows promise for visual and fluorometric sensing platforms aimed at humidity or ethanol detection.
关键词： Dual-emission,Humidity,Sensing paper,Ethanol,Visualization
更新于2025-09-10 09:29:36
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Synthesis of Sn-doped ZnO hierarchical particles and their gas-sensing properties
摘要： In this work, un-doped and Sn-doped hierarchical ZnO particles with high dispersity were successfully fabricated by a facile liquid reaction. The prepared samples are characterised by X-ray diffraction and scanning electron microscopy. The as-synthesised hierarchical ZnO particles with a diameter of ～1.5 μm were obtained by considerably intersecting thin nanosheets of ～20 nm thickness. The morphology of ZnO structures can be varied by adjusting reaction parameters, e.g. reaction temperature, calcination temperature, and dopant concentration. On the basis of experimental results, the gas-sensing measurement displays that the sensor based on Sn-doped ZnO microstructures have a low detection of 10 ppm ethanol at an operational temperature of 250°C, demonstrating its outstanding gas-sensing performance. Therefore, the ?ower-like Sn-doped ZnO have prospective applications in a multifunction ethanol sensor. Moreover, the fabrication method reported in the work is facile, ?exible and operable, it is possible to extend to synthesise other types of metal oxide-based applications in various ?elds.
关键词： Sn-doped ZnO,hierarchical particles,facile liquid reaction,gas-sensing properties,ethanol sensor
更新于2025-09-10 09:29:36
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Highly efficient ethanol gas sensor based on hierarchical SnO2/Zn2SnO4 porous spheres
摘要： In this work, hierarchucal porous SnO2/Zn2SnO4 nanospheres were succesfully prepared via a facile one-step hydrothermal method with subsequent calcination process. Scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were employed in order to investigate the structural and morphological properties of the as-prepared composites. The results showed that the SnO2/Zn2SnO4 composites were cpmposed of many porous nanospheres with a uniform diameter of about 500 nm. Moreover, the as-prepared products were used as sensing material for the fabrication of gas sensor. The sensing performance of the sensor was systematically evaluated, and the sensor exhibited excellent ethanol-sensing property. The optimum operating temperature was 250 oC with a reponse of 30.5 toward 100 ppm ethanol. Also, the sensor showed good selectivity, stability and a low detection limit of 0.5 ppm (response 1.4). The good sensing performance of SnO2/Zn2SnO4 nanospheres can be attibuted to the porous structure as well as the heterojunction formed between SnO2 and ZnSn2O4.
关键词： SnO2/Zn2SnO4,Porous sphere,Hydrothermal method,Ethanol,Gas sensor
更新于2025-09-09 09:28:46
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Highly sensitive gas sensor based on Er-doped SnO2 nanostructures and its temperature dependent selectivity towards hydrogen and ethanol
摘要： In the present work, impact of Er3+ doping on the response and selectivity of SnO2 based gas sensor has been investigated in detail. X-ray diffraction (XRD) results confirmed formation of a tetragonal rutile structure of undoped and erbium doped SnO2 nanoparticles. It has been observed that specific surface area of nanoparticles has increased with increase in dopant concentration. The oxidation states and presence of erbium in SnO2 lattice has been confirmed by X-ray photoelectron spectroscopy (XPS). Photoluminescence (PL) analysis revealed that concentration of oxygen vacancies increases with increase in dopant incorporation. It has been observed that 3% Er-doped SnO2 sensor exhibited enhanced sensor response and temperature dependent selectivity towards ethanol and hydrogen at 240 and 360℃ respectively. The enhanced sensor response of the fabricated sensor has been ascribed to large surface area, enormous oxygen vacancies and elevated surface basicity of doped nanoparticles used. The tunable dual selectivity of 3% doped sensor towards ethanol and hydrogen makes it a perfect candidate for ethanol-hydrogen sensing for ethanol steam reforming systems combined to fuel cells.
关键词： hydrogen,nanoparticles,ethanol,gas sensor,selectivity
更新于2025-09-09 09:28:46