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Search results for: phonon calculations
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Solvent effects for proton transfer reaction from dimethyl(4-nitrophenyl)malonate to cis 1,2-bis(diethylaminomethyl)cyclohexane
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FTIR, NMR and kinetic studies of proton transfer reactions from nitro-substituted diarylmethanes to N-bases with guanidine character
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Non-stoichiometric magnetite as catalyst for the photocatalytic degradation of phenol and 2,6-dibromo-4-methylphenol – a new approach in water treatment
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Immobilization of TiO2 and Fe–C–TiO2 photocatalysts on the cotton material for application in a flow photocatalytic reactor for decomposition of phenol in water
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The kinetics of phenol decomposition under UV irradiation with and without H2O2 on TiO2, Fe–TiO2 and Fe–C–TiO2 photocatalysts
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Influence of temperature and nitrogen pressure on the test without active gases for high-temperature proton exchange membrane fuel cells
PublicationHigh-Temperature Proton-Exchange Membrane Fuel Cells (HT-PEMFCs) are a candidate for electrical energy supply devices in more and more applications. Most notably in the aeronautic industry. Before any use, an HT-PEMFC is preheated and after that supplied with its active gases. Only at this state, the diagnostics can be performed. A method of testing not requiring a complete start-up would be beneficial for many reasons. This article...
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Online Volatile Compound Emissions Analysis Using a Microchamber/Thermal Extractor Coupled to Proton Transfer Reaction-Mass Spectrometry
PublicationIndoor air is a complex and dynamic mixture comprising manifold volatile organic compounds (VOCs) that may cause physiological and/or psychological discomfort, depending on the nature of exposure. This technical note presents a novel approach to analyze VOC emissions by coupling a microchamber/thermal extractor (μ-CTE) system to a proton transfer reaction-mass spectrometer (PTR-MS). This configuration provides an alternative to...
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Photoactivity of decahedral TiO2 loaded with bimetallic nanoparticles: Degradation pathway of phenol-1- 13 C and hydroxyl radical formation
PublicationDecahedral TiO2decorated with bimetallic nanoparticles were synthesized via radiolysis and photode-position method. The effect of bimetallic surface composition (Ag Pt, Ag Au, Au Pd, Au Pt) as well asdeposition technique (simultaneous or sequential) on the photocatalytic activity in phenol degradationand efficiency of hydroxyl radicals generation under UV–vis light irradiation were investigated. Modifiedand pristine decahedral...
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Monitoring of odors emitted from stabilized dewatered sludge subjected to aging using proton transfer reaction–mass spectrometry
PublicationOne of the potential emission sources of odorous compounds from wastewater treatment plants is sludge processing. The odorous compounds released from dewatered sludge can result in odor nuisance. This study concerns the use of flux hood chamber combined with proton transfer reaction—time of flight—mass spectrometry (PTR-MS) technique for periodical monitoring of odorous compounds emitted from aged, stabilized dewatered sludge samples...
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Direct measurements of odorous volatile organic compounds present in biosolids cakes by Proton Transfer Reaction – Mass Spectrometry Technique
PublicationThis paper show the results of investigation of concentration of odorous chemical compounds emitted upon ageing of anaerobically stabilised biosolids that could contribute to the overall odour character of nuisance emissions. Biosolids samples from wastewater treatment plant were collected in spring time. Concentrations of volatile organic compounds using a US EPA flux hood and Proton Transfer Reaction-Time of Flight-Mass Spectrometry...
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On-line assessment of oil quality during deep frying using an electronic nose and proton transfer reaction mass spectrometry
PublicationWe describe a novel method for the quality assessment of oil utilized for deep frying. The method is based on the analysis of frying fumes using a custom electronic nose. The quality score could be obtained after less than 3 min of analysis and without interrupting the frying process or sampling the oil directly. The obtained results were correlated with the peroxide value using a multivariate linear regression model. The most...
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The impact of air humidity on the operation of proton exchange membrane fuel cells determined using dynamic electrochemical impedance spectroscopy
PublicationThis paper describes the changes in the fuel cell impedance across a range of current loads and humidity changes. The changes of each equivalent circuit parameters representing specific processes occurring in fuel cells, as a function of humidity and current changes, were determined. Within the combined scope of current and humidity, the optimal working conditions of the cells were determined, corresponding to the lowest impedance...
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Impact of dyes isomerization effect on the charge transfer phenomenon occurring on the dye/nanosemiconductor interface
PublicationThe present work aimed to find the answer how does the isomerization of the Ru based dyes affect the overall photon-to-current efficiency of the DSSCs and to explain the charge transfer phenomenon occurring on the dye/ nanosemiconductor interface. Therefore, electronic and optical properties of three bipyridine derivatives anchored on the TiO2 electrode were investigated by computational simulations based on quantum chemistry codes...
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Preparation and Characterization of Au/Pd Modified-TiO2 Photocatalysts for Phenol and Toluene Degradation under Visible Light—The Effect of Calcination Temperature
PublicationRutile loaded with Au/Pd nanoparticles was prepared using a water-in-oil microemulsion system of water/AOT/cyclohexane followed by calcination.Theeffect of calcination temperature (from350 to 700∘C) on the structure ofAu/Pd nanoparticles deposited at rutile matrix and the photocatalytic properties of Au/Pd-TiO2 was investigated in two model reactions (toluene degradation in gas phase and phenol degradation in aqueous phase). The...
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Structure of single KL0–, double KL1–, and triple KL2 − ionization in Mg, Al, and Si targets induced by photons, and their absorption spectra
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Phenol-rich alternatives for Rosa x damascena Mill. Efficient phytochemical profiling using different extraction methods and colorimetric assays
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Validation of high-resolution 3D patient QA for proton PBS and IMPT using laser CT of improved polymer gel dosimeters
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Kinetic and equilibrium studies of the proton and deuteron transfer reaction between bis(2,4-dinitrophenyl)methane and strong nitrogen bases in acetonitrile
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SU‐E‐T‐103: Three‐Dimensional Measurements of Dose and LET from a Proton Beam via Polymer Gel Dosimetry
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WITHDRAWN: The kinetics of phenol decomposition under UV irradiation with and without H2O2 on TiO2, Fe-TiO2 and Fe-C-TiO2 photocatalysts
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Electrochemical performance of Co3O4/CeO2 electrodes in H2S/H2O atmospheres in a proton-conducting ceramic symmetrical cell with BaZr0.7Ce0.2Y0.1O3 solid electrolyte
PublicationThe electrochemical performance of Co3O4/CeO2 mixed oxide materials as electrodes, when exposed to H2S/H2O atmospheres, was examined employing a proton conducting symmetrical cell, with BaZr0.7Ce0.2Y0.1O3 (BZCY72) as the solid electrolyte. The impact of temperature (700–850 °C) and H2S concentration (0–1 v/v%) in steam-rich atmospheres (90 v/v% H2O) on the overall cell performance was thoroughly assessed by means of electrochemical...
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Computational analysis of substituent effects on proton affinity and gas-phase basicity of TEMPO derivatives and their hydrogen bonding interactions with water molecules
PublicationThe study investigates the molecular structure of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) and its derivatives in the gas phase using B3LYP and M06-2X functional methods. Intermolecular interactions are analyzed using natural bond orbital (NBO) and atoms in molecules (AIM) techniques. NO2-substituted TEMPO displays high reactivity, less stability, and softer properties. The study reveals that the stability of TEMPO derivatives...
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Pendant Proton-Relays Systematically Tune the Rate and Selectivity of Electrocatalytic Ammonia Generation in a Fe-Porphyrin Based Metal-Organic Framework
PublicationElectrocatalytic nitrite reduction (eNO2RR) is a promising alternative route to produce ammonia (NH3). Until now, several molecular catalysts have shown capability to homogeneously reduce nitrite to NH3, while taking advantage of added secondary-sphere functionalities to direct catalytic performance. Yet, realizing such control over heterogeneous electrocatalytic surfaces remains a challenge. Herein, we demonstrate that heterogenization...
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Complementary Use of Multi-dimensional Gas Chromatography and Proton Transfer Reaction Mass Spectrometry for Identification of Rapeseed Oil Quality Indicators
PublicationThe change of concentration of various volatiles generated during frying may be an indicator of oil quality. Chemical compounds such as aldehydes, ketones, alcohols and carboxyl acids are the products of oxidation during thermal degradation of edible oils. Shown in this work is a complementary use of GC×GC-TOFMS and PTR-MS for the detection and determination of quality indicators of rapeseed oil. The former technique was used for...
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An integral-differential method for impedance determination of the hydrogen oxidation process in the presence of carbon monoxide in the proton exchange membrane fuel cell
PublicationThe impedance of a proton exchange membrane fuel cell powered by hydrogen contaminated with carbon monoxide, ranging from 150 to 300 ppb, is measured and discussed. The tested range of CO concentration complied with the fuel standard specified in the ISO standards. Studies of influence of CO contamination on operation of PEMFC are crucial for further development and commercialization of fuel cells for automotive applications. Based...
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A study of the photoelectron spectra of α-tetrahydrofurfuryl alcohol over the outer valence energy region (9–25 eV)
PublicationPhotoelectron spectra of α-tetrahydrofurfuryl alcohol (THFA) molecules, the threshold spectrum and spectra for constant photoelectron energies, have been measured over the photon energy range 9–25 eV. Analysis of the photoelectron spectra has allowed overlapping photoionization bands to be separated, tentatively assigned and their vertical photoionization energies to be determined. These energies are compared with existing theoretical...
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A TPC Detector for Studying Photo-nuclear Reactions at Astrophysical Energies with Gamma-ray Beams at ELI--NP
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Photodecomposition of dyes on Fe-C-TiO2 photocatalysts under UV radiation supported by photo-Fenton process
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The pulsed laser ablation synthesis of colloidal iron oxide nanoparticles for the enhancement of TiO2 nanotubes photo-activity
PublicationThe rapid, only a few minutes long synthesis of FeO, Fe3O4, and Fe2O3nanoparticles mixture utilizing the pulsedlaser ablation using simply pure iron target and water was demonstrated. The size and crystal phase of Fe-basedNPs were characterized using DLS and HR-TEM techniques, respectively. The metastable suspension of FeO,Fe3O4, and Fe2O3nanoparticles was used to the decoration of anodized TiO2nanotubes (TiO2-NTs) by means ofthe...
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Photo-elastic and DIC techniques to study development of dilatant and compaction shear bands within granular materials
PublicationW artykule omówiono wyniki doświadczalne w odniesieniu do rozwoju stref ścinania w materiałach granulowanych. Wyniki stref ścinania otrzymano stosując metodę foto-sprężystą oraz technikę korelacji cyfrowych obrazów DIC. Pokazano zalety i wady obu metod to wykrywania stref scinania.
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Superconducting properties and electronic structure of NaBi
PublicationResistivity, dc magnetization, and heat capacity measurements are reported for superconducting NaBi. Tc, the electronic contribution to the specific heat γ, the ΔCp/γTc ratio, and the Debye temperature are found to be 2.15 K, 3.4 mJ mol−1 K−2, 0.78, and 140 K respectively. The calculated electron–phonon coupling constant (λep = 0.62) implies that NaBi is a moderately coupled superconductor. The upper critical field and coherence...
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Experimental generation of complex noisy photonic entanglement
PublicationWe present an experimental scheme based on spontaneous parametric down-conversion to produce multiple-photon pairs in maximally entangled polarization states using an arrangement of two type-I nonlinear crystals. By introducing correlated polarization noise in the paths of the generated photons we prepare mixed-entangled states whose properties illustrate fundamental results obtained recently in quantum information theory, in particular those...
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Monte-Carlo Modeling of Optical Sensors for Postoperative Free Flap Monitoring
PublicationThis work aims to develop a numerical tissue model and implement software to simulate photon propagation using the Monte Carlo method to determine design guidelines for a physical measurement system. C++ was used for the simulation program, and Python as a programming environment to create an interface that allows the user to customize individual simulation elements, allowing for increased accuracy and flexibility when simulating...
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Monte-Carlo Modeling of Optical Sensors for Postoperative Free Flap Monitoring
PublicationThis work aims to develop a numerical tissue model and implement software to simulate photon propagation using the Monte Carlo method to determine design guidelines for a physical measurement system. C++ was used for the simulation program, and Python as a programming environment to create an interface that allows the user to customize individual simulation elements, allowing for increased accuracy and flexibility when simulating...
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Equivalent temperature for design of airport pavements using mechanistic-empirical methods
PublicationThe paper presents implementation of equivalent temperature for design of airport asphalt pavements. The calculation methods of equivalent temperature: the Shell method, the French method and method that use the Asphalt Institute fatique criteria were presented. An example of calculations of equivalent temperature for Gdansk Airport was introduced and discussed. It was shown that methods of calculation of equivalent temperature...
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3D dose verification with polymer gel detectors of brain-spine match line for proton pencil beam cranio-spinal: A preliminary study
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The antioxidant and antimicrobial properties of phenol-rich extracts of Dracocephalum forrestii W. W. Smith shoot cultures grown in the nutrient sprinkle bioreactor
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Analysis of volatile fraction of sweetie (Citrus maxima × Citrus paradisi) and its parent fruit using proton transfer reaction mass spectrometry
PublicationThe quality of the fruit is affected by several main ingredients and the aroma plays a fundamental role during the selection of fruit by consumers. In the case where several fruit have similar aromas and only one of them has specific health properties, it is very important to find the differences in the volatile organic compounds (VOCs) composition to distinguish these samples. Such situations are often found for hybrid fruit....
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A new method for real-time monitoring of volatiles in frying fumes using proton transfer reaction mass spectrometry with time-of-flight analyse
PublicationTo safeguard the consumers’ well-being, it is necessary to develop novel methods for determination of carcinogens in food, including volatiles generated during frying. The currently used procedures for analysis of volatile fraction of vegetable oils are not based on real-time measurements and thus do not enable the determination of carcinogenic compounds in frying fumes; instead, only the headspace or liquid fraction is sampled....
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Investigation of the Dynamism of Nanosized SOA Particle Formation in Indoor Air by a Scanning Mobility Particle Sizer and Proton-Transfer-Reaction Mass Spectrometry
PublicationTerpenes are VOCs of particular importance, since they are emitted from a wide range of indoor sources and are considered to be precursors of Secondary Organic Aerosol (SOA) formation. It has been proven that SOA particles, especially nanosized ones, pose a threat to human health. In this research, experiments with the application of an environmental chamber and real-time measurement techniques were carried out to investigate in...
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Imidazolium silanethiolates relevant to the active site of cysteineproteases. A cooperative effect in a chain of NH(+)...S(-) hydrogenbonds
PublicationThree imidazolium silanethiolates relevant to the active site of cysteine proteases have been synthesized and investigated by X-ray diffraction, IR spectroscopy and computational methods. As indicated by crystallographic and FT-IR data in the solid state, the transfer of proton from thiol to imidazole takes place and a thiolato-imidazolium ion pair is formed. The FT-IR spectra of crystalline imidazolium silanethiolates exhibit...
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Superconducting SrSnP with Strong Sn–P Antibonding Interaction: Is the Sn Atom Single or Mixed Valent?
PublicationThe large single crystals of SrSnP were prepared using Sn self-flux method. The superconductivity in the tetragonal SrSnP is observed with the critical temperature of ∼2.3 K. The results of a crystallographic analysis, superconducting characterization, and theoretical assessment of tetragonal SrSnP are presented. The SrSnP crystallizes in the CaGaN structure type with space group P4/nmm (S.G. 129, Pearson symbol tP6) according...
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Visible light photocatalytic activity of ionic liquid-TiO2 spheres: effect of the ionic liquid's anion structure
PublicationThe effect of the ionic liquid’s (IL) anion type ([BIMIM][X], where X= [Br], [PF6] or [OctSO4]) and content on the morphology, surface properties and photoactivity of TiO2 obtained by solvothermal method has been systematically investigated. Our results revealed that the presence of [Br], [OctSO4] anions favors formation of anatase phase, while presence of [PF6] anion causes formation of mixture of anatase and Ti(OH)PO4 phases....
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Studying the governing factors on the photo(electro)catalytic activity of surface-modified photocatalysts under visible light illumination
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Contact force network evolution in active earth pressure state of granular materials: photo‑elastic tests and DEM
PublicationArtykuł omawia ewolucję sieci sił kontaktowych w materiałach granulowanych podczas quasi-statycznego stanu aktywnego. Doświadczenia foto sprężyste zostały wykonane dla kulek szklanych. Doświadczenia zostały symulowane stosując metodę elementów dyskretnych (DEM). Model DEM prawidłowo przewidział strukturę sił kontaktowych i ich wielkość, lokalizację odkształceń oraz obszary zmian fazowych.
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Determinants of Directionality and Efficiency of the ATP Synthase Fo Motor at Atomic Resolution
PublicationFo subcomplex of ATP synthase is a membrane-embedded rotary motor that converts proton motive force into mechanical energy. Despite a rapid increase in the number of high-resolution structures, the mechanism of tight coupling between proton transport and motion of the rotary c-ring remains elusive. Here, using extensive all-atom free energy simulations, we show how the motor’s directionality naturally arises from the interplay...
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Simple Physics-Based Analytical Formulas for the Potentials of Mean Force for the Interaction of Amino Acid Side Chains in Water. 3. Calculation and Parameterization of the Potentials of Mean Force of Pairs of Identical Hydrophobic Side Chains
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Physical properties and electronic structure of La3Co and La3Ni intermetallic superconductors
PublicationLa3Co and La3Ni are reported superconductors with transition temperatures of 4.5 and 6 K, respectively. Here, we reinvestigate the physical properties of these two intermetallic compounds with magnetic susceptibility χ, specific heat Cp and electrical resistivity ρ measurements down to 1.9 K. Although bulk superconductivity is confirmed in La3Co, as observed previously, only a trace of it is found in La3Ni, indicating that the...
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Monitoring the BTEX Volatiles during 3D Printing with Acrylonitrile Butadiene Styrene (ABS) Using Electronic Nose and Proton Transfer Reaction Mass Spectrometry
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Adaptation of phenol-degrading Pseudomonas putida KB3 to suboptimal growth condition: A focus on degradative rate, membrane properties and expression of xylE and cfaB genes
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