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Wyniki wyszukiwania dla: MATRIX ASSISTED LASER DESORPTION IONIZATION–MASS SPECTROMETRY
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Application of Headspace Solid-phase Microextraction with Poly(1-vinyl-3- Hexylimidazolium Chloride) Polymeric Ionic Liquid Coating using GC - MS to Determine Volatile Fatty Acids in Dairy Wastewater
PublikacjaVolatile fatty acids were determined in this study using headspace solid-phase microextraction (HS-SPME) with a poly(1-vinyl-3-hexylimidazolium chloride) polymeric ionic liquid coated fiber followed by gas chromatography - mass spectrometry. Experimental parameters such as extraction time and temperature, sample volume as well as desorption time and temperature were optimized. Detection limits of the method were in the range of...
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The difficulties in polybrominated diphenyl ethers identification by GC-EI-MS technique
PublikacjaAwareness about the harmful effects of brominated flame retardants on living organisms increases mainly due to link their presence in the human environment with health disorders. Therefore is a need to conduct research aimed at content control of these chemicals in the environment. Recent improvements in injection techniques and mass spectrometer ionization methods have led to a variety of options to determine PBDEs in environmental...
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Electron impact ionization and cationic fragmentation of the pyridazine molecules
PublikacjaElectron impact mass spectroscopy was used to investigate ionization and cationic fragmentation of the pyridazine (1,2 diazine), C4H4N2, molecules in the gas phase. The mass spectra were measured and the observed mass peaks assigned to the corresponding cations. The appearance energies of most of the cationic fragments were determined and the possible fragmentation processes are discussed. The total cross section for electron...
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Cross sections for ionization and ionic fragmentation of pyrimidine molecules by electron collisions
PublikacjaThe electron impact mass spectroscopy and the total ion collection measurements were used to investigate the ionization and ionic fragmentation of the pyrimidine, C4H4N2, molecules in the gasphase. The cation mass spectra were measured in the 10−85 amu range and the observed mass peaks assigned to corresponding ionic fragments. The most abundant cation in the mass spectra is the parent cation, C4H4N+2, at 80 amu. The appearance...
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Concentration levels of selected analytes in the gas phase of an e-cigarette aerosol
PublikacjaThe aerosols generated from e-cigarettes are composed of liquid and gas phases resulting from vapourized e-liquid. The apportioning of substances from e-liquid into the liquid and gas phases during e-cigarette use has not been extensively studied. Partitioning of e-liquid components between the gas and the liquid phase of the aerosol influences the substances inhaled and exhaled by the users, leading to second-hand exposure. It...
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The dispersive micro-solid phase extraction method for MS-based lipidomics of human breast milk*
PublikacjaA simple and rapid microextraction method ensuring high lipidome coverage was developed for liquid chromatography mass spectrometry (LC-MS)-based lipidomics of human breast milk. The dispersive microsolid phase extraction (D-µ-SPE) technique, coupled with the design of experiment (DoE) method, enabled the study of the influence of several conditions (desorption solvent, stationary phase ratio, and sorption and desorption time)...
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Hydrophobic deep eutectic solvents as “green” extraction media for polycyclic aromatic hydrocarbons in aqueous samples
PublikacjaThe paper presents novel nonionic and hydrophobic deep eutectic solvents which were synthesized from natural compounds, i.e., thymol, ±camphor, decanoic and 10-undecylenic acids. Fundamental physicochemical properties of the synthesized deep eutectic solvents were determined, followed by their application as extractants in ultrasound-assisted dispersive liquid-liquid microextraction to isolate and enrich polycyclic aromatic hydrocarbons...
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Dopants and gas modifiers in ion mobility spectrometry
PublikacjaThe ion mobility techniques, including the most commonly used drift-tube ion mobility spectrometry (IMS) and differential mobility spectrometry (DMS), are used successfully for the detection of a wide range of organic compounds in the gas phase. In order to improve detection quality, admixtures are added to gas streams flowing through the detector. Dopants mostly prevent the ionization of interfering chemicals however, better detection...
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Ionization and fragmentation of furan molecules by electron collisions
PublikacjaCation mass spectra obtained by electron impact were measured to investigate the ionization and ionic fragmentation of furan, C4H4O, molecules in the gas phase. The most abundant cations, with comparable intensities in the mass spectra, were the parent, C4H4O+, cation (68 amu) and the C3H3+ fragment (39 amu). The appearance energies of most of the observed ionic fragments were determined and the possible fragmentation processes...
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Determination of Terpene Profile in Cape gooseberry (Physalis peruviana L.) with Use of HS-SPME/GCxGC-TOFMS Method
PublikacjaFresh fruits and products made of them, especially fruit juice, provide the basic energetic substances (simple and complex sugars) and are a source of health beneficial vitamins, macro and microelements, antioxidants and compounds which are classified together with essential oils (for example terpenes), which positively affect human s health. The terpenes profile of cape gooseberry was determined by headspace solid--phase microextraction...
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In-tube extraction for the determination of the main volatile compounds in Physalis peruviana L
PublikacjaAn analytical procedure based on in-tube extraction followed by gas chromatography with mass spectrometry has been developed for the analysis of 24 main volatile components in cape gooseberry (Physalis peruviana L.) samples. According to their chemical structure, the compounds were organized into different groups: one hydrocarbon, one aldehyde, four alcohols, four esters, and 14 monoterpenes. By single-factor experiments, incubation...
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Determination of the substances potentially allergenic in water
PublikacjaPersonal care chemicals are continuously released into environment through domestic and industrial wastewater, causing adverse effects on human health. Their presence can be detected in different environmental compartments. A group of chemicals included in most personal care products are the allergen fragrances. In the present work, simple and rapid methodology based on ultrasound-assisted emulsification-microextraction (USAEME)...
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Understanding the early-stage release of volatile organic compounds from rapeseed oil during deep-frying of tubers by targeted and omics-inspired approaches using PTR-MS and gas chromatography
PublikacjaDuring deep-frying, a plethora of volatile products is emitted with the fumes. These compounds could act as oil quality indicators and change the indoor air composition leading to health risks for occupants. The presented experiments focus on deep-frying of different tubers in rapeseed oil at different frying temperatures. Here, two scenarios for real-time monitoring of volatile organic compounds (VOCs) using proton transfer reaction...
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Matrix solid-phase dispersion (MSPD) as simple and useful sample preparation technique for determination of polybrominated diphenyl ethers (PBDEs) in dust
PublikacjaIn the present study a novel analytical procedure for the determination of polybrominated diphenylethers in dust samples was developed.The main aim of the research was the selection of the optimum conditions of the matrix solid-phasedispersion before thefinal determination of polybrominated diphenyl ethers in dust samples. In order toassess the best usefulness of this technique, a favourable ratio of sample amount to the mass ofdispersing...
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Pesticide residues levels in honey from apiaries located of Northern Poland
PublikacjaConcentration levels of 30 pesticide residues were measured in honey samples collected from apiaries in northern part of Poland (Pomerania) using method based on the QuEChERS extraction followed by liquid chromatography-tandem mass spectrometry with electron spray ionization (LC-ESI-MS/MS). In 29% of the samples were found positive for at least some of the target compounds. Concentration of bifenthrin, fenpyroximate, methidathion,...
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Chemical and biological characterization of Ocimum basilicum L. phenolic extract and essential oil derived through ultrasound and microwave-assisted extraction techniques
PublikacjaPlant-derived bioactive molecules are increasingly utilized in food processing as natural additives, driven by a growing interest in healthier lifestyles. This trend has spurred industries to reformulate products to meet the demands of health-conscious consumers. This study investigates the phenolic extract and essential oil of O. basilicum L. obtained via ultrasound-assisted extraction and microwave-assisted extraction, respectively. Characterization...
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Multi-Technique Investigation of Grave Robes from 17th and 18th Century Crypts Using Combined Spectroscopic, Spectrometric Techniques, and New-Generation Sequencing
PublikacjaThe textile fragments of the funeral clothes found in the 17th and 18th century crypts were subjected to spectroscopic, spectrometric, and microbial investigation. The next-generation sequencing enabled DNA identification of microorganisms at the genus and in five cases to the species level. The soft hydrofluoric acid extraction method was optimized to isolate different classes of dyes from samples that had direct contact with...
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Electrochemical simulation of metabolism for antitumor-active imidazoacridinone C-1311 and in silico prediction of drug metabolic reactions
PublikacjaThe metabolism of antitumor-active 5-diethylaminoethylamino-8-hydroxyimidazoacridinone (C-1311) has been investigated widely over the last decade but some aspects of molecular mechanisms of its metabolic transformation are still not explained. In the current work, we have reported a direct and rapid analytical tool for better prediction of C-1311 metabolism which is based on electrochemistry (EC) coupled on-line with electrospray...
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Recent Applications of 1D GC-MS and 2D GC-MS in Foodomics Studies
PublikacjaGas chromatography coupled with mass spectrometry and food chemistry have been tightly linked since the 1960s. This setup is also an integral part of the omics studies when it comes to low mass metabolites. Therefore, the marriage of GC-MS and foodomics is obvious. Two-dimensional gas chromatography coupled with mass spectrometry fits perfectly within the latest trends in foodomics, since it is tailored for holistic food analysis....
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Application of ultrasound-assisted solvent extraction of porous membrane packed liquid samples for polyphenols determination in wine samples
PublikacjaPolyphenols play a crucial role in a proper human health maintenance as well as their presence very often correspond to the quality assessment of producs like wine. Thus, their monitoring is of high interest. However, as they occur in a complex matrices their extraction is very often necessary prior the analysis. Herein, a new ultrasound-assisted solvent extraction of porous membrane packed liquid sample technique has been optimized...
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The use of HPLC-Q-TOF-MS for comprehensive screening of drugs and psychoactive substances in hair samples and several “legal highs” products
PublikacjaNon-targeted screening of drugs present in herbal products, known as “legal high” drugs and in hair as a biological matrix commonly used in toxicological investigations was accomplished with the use of high pressure liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF-MS). In total, 25 and 14 therapeutical drugs and psychoactive substances/metabolites were detected in investigated hair samples...
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Nowe substancje psychoaktywne Cz. III. Syntetyczne katynony-charakterystyka, metody oznaczania i wyzwania analitycznje
PublikacjaSyntetyczne katynony to druga co do liczebności (po syntetycznych kannabinoidach) grupa nowych substancji psychoaktywnych będących składnikiem dopalaczy zabezpieczanych przez policję w nielegalnym handlu. Substancje te po raz pierwszy wykryto w Europie w 2004 r., a do końca roku 2015 zidentyfikowano aż 103 nowe związki z tej grupy. Możliwość wprowadzania dodatkowych grup funkcyjnych w strukturę katynonu pozwala na niezwykle wiele...
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Soft X-ray Induced Production of Neutral Fragments in High-Rydberg States at the O 1s Ionization Threshold of the Water Molecule
PublikacjaDissociation of water molecules after soft X-ray absorption can yield neutral fragments in high-Rydberg (HR) states. We have studied the production of such fragments by field ionization and ion time-of-flight (TOF) spectrometry. Neutral HR fragments are created at all resonances below the O 1s ionization potential (IP) and particularly within 1 eV above the O 1s IP. The latter effect is due to the recapture of the O 1s photoelectrons...
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Wear Resistance Enhancement of Al6061 Alloy Surface Layer by Laser Dispersed Carbide Powders
PublikacjaIn this paper, results of the experimental study on improving wear resistance in sliding friction of Al-based alloy are presented. The technique used involves the formation of a metal matrix composite (MMC) in the alloy surface layer by laser dispersion of carbide powders such as WC, TiC and SiC. For WC and TiC MMC surface coatings fabricated under conditions typical for most of the technologically relevant solid-state lasers (wavelength...
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Multi-residue method for the determination of 16 recently used pesticides from various chemical groups in aqueous samples by using DI - SPME coupled with GC-MS
PublikacjaA simple and solvent-free multi-residue method has been optimized to determine 16 currently used pesticides from different chemical groups in aqueous samples. The extraction of analytes was carried out with direct immersion solid-phase microextraction (DI-SPME) and for the identification and quantitative determination gas chromatography coupled with mass spectrometry (GC-MS) was applied. Two commonly used adsorbent coatings have...
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Research on the separation properties of empty-column gas chromatography (EC-GC) and conditions for simulated distillation (SIMDIS)
PublikacjaThe paper presents the results of investigations on new procedures of determination of selected cleaning additives in diesel fuel. Two procedures: one-step analysis using gas chromatography with flame ionization detection (GC-FID) or mass spectrometry (GC-MS) and a two-step procedure in which normal-phase high-performance liquid chromatography (NP-HPLC) was used for preliminary separation of the additives, were compared. The additive...
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Application of normal-phase high-performance liquid chromatography followed by gas chromatography for analytics of diesel fuel additives
PublikacjaThe paper presents the results of investigations on new procedures of determination of selected cleaning additives in diesel fuel. Two procedures: one-step analysis using gas chromatography with flame ionization detection (GC-FID) or mass spectrometry (GC-MS) and a two-step procedure in which normal-phase high-performance liquid chromatography (NP-HPLC) was used for preliminary separation of the additives, were compared. The additive...
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Yields and Time-of-Flight Spectra of Neutral High-Rydberg Fragments at the K Edges of the CO2 Molecule
PublikacjaWe have studied the production of neutral fragments in high-Rydberg (HR) states at the C 1s and O 1s edges of the CO2 molecule by performing two kinds of experiments. First, the yields of neutral HR fragments were measured indirectly by ionizing such fragments in a static electric field and by collecting resulting singly charged positive ions as a function of the photon energy. Such measurements reveal not only excitations below...
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Simultaneous determination of ibuprofen and its metabolites in complex equine urine matrices by GC-EI-MS in excretion study in view of doping control
PublikacjaA novel assay for the simultaneous determination of ibuprofen (IBU) and its four probable metabolites, 1-hydroxyibuprofen (1-OH IBU), 2-hydroxyibuprofen (2-OH IBU), 3-hydroxyibuprofen (3-OH IBU) and carboxyibuprofen (CBX IBU) in equine urine samples with the application of Gas Chromatography-Electron Ionization-Mass Spectrometry (GC-EI-MS) has been developed and elaborated. The new approach for sample preparation including minimizing...
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Determination of polybrominated diphenyl ethers in house dust using standard addition method and gas chromatography with electron capture and mass spectrometric detection
PublikacjaMonitoring of the environmental fate of polybrominated diphenyl ethers (PBDEs) involves determination of their concentration in air, airborne particles and settled dust. This requires the implementation of appropriate analytical tools like measuring instruments, reference materials and analytical procedures. In this study an analytical procedure was developed for determining PBDEs in samples with a complex matrix composition. The...
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Funcionality assessment of Citrus Hysteria peel as a protective barrier using gas chromatography
PublikacjaThe aim of this study was to analyse the volatile fractions of fruit peel and pulp using two-dimensional gas chromatography technique coupled with mass spectrometry. The isolation of the compounds was achieved by microextraction to the stationary phase from the headspace of the sample (HS-SPME). Mass spectrometry with time-of-flight analyser (TOF-MS) was used to identify the chemical compounds. There are no reports in the literature...
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Fabrication and photoactivity of organic-inorganic systems based on titania nanotubes and PEDOT containing redox centres formed by different Prussian Blue analogues
PublikacjaHerein, the heterojunction composed of an inorganic substrate: ordered hydrogenated titania nanotubes (H-TiO2NTs) and a deposited organic film: poly(3,4-ethylenedioxythiophene) (PEDOT) is reported. The conducting polymer is modified with different transition metal haxacyanoferrates (Mehcf), wherein as metal: copper, iron, cobalt and nickel are introduced. The presence of various metal centres provides characteristic redox activity...
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Influence of reactive oxygen species during deposition of iron oxide films by high power impulse magnetron sputtering.
PublikacjaIron oxide films were deposited using high power impulse magnetron sputtering (HiPIMS) of an iron cathode in an argon/oxygen gas mixture at different gas pressures (0.5~Pa, 1.5~Pa, and 5.0~Pa). The HiPIMS system was operated at a repetition frequency $f = 100$~Hz with a duty cycle of 1~\%. A main goal is a comparison of film growth during conventional and electron cyclotron wave resonance-assisted HiPIMS. The deposition plasma...
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Bisphenols and their derivatives in baby diaper samples.
PublikacjaMany common products contain and leach hazardous chemicals, including endocrine-disrupting chemicals such as bisphenols that are harmful to human health. For toddlers, this dangerousness is higher because of their not fully developed detoxification system. Due to this, bisphenols content in products such as baby diapers, should be monitored. Baby diapers not only remain in close contact with the skin, but are also used from the...
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Chemical Composition of Atmospheric Air in Nemoral Scots Pine Forests and Submountainous Beech Forests: The Potential Region for the Introduction of Forest Therapy
PublikacjaStudies show that forests are one of the main recreational destinations. This can be explained by their beneficial effects on the health of their visitors, which can be attributed to compounds from the terpene group. The aim of this research was to determine the chemical composition of air in the interiors of Nemoral Scots pine forests and submountainous beech forests, with the determination of compounds of the terpene group. Samples...
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Processing, Performance Properties, and Storage Stability of Ground Tire Rubber Modified by Dicumyl Peroxide and Ethylene-Vinyl Acetate Copolymers
PublikacjaIn this paper, ground tire rubber was modified with dicumyl peroxide and a variable content (in the range of 0–15 phr) of ethylene-vinyl acetate copolymers characterized by different vinyl acetate contents (in the range of 18–39 wt.%). Modification of ground tire rubber was performed via an auto-thermal extrusion process in which heat was generated during internal shearing of the material inside the extruder barrel. The processing,...
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Electrochemical and in silico approaches for liver metabolic oxidation of antitumor-active triazoloacridinone C -1305
Publikacja5-Dimethylaminopropylamino-8-hydroxytriazoloacridinone (C-1305) is a promising antitumor compound developed in our laboratory. A better understanding of its metabolic transformations is still needed to explain the multidirectional mechanism of pharmacological action of triazoloacridinone derivatives at all. Thus, the aim of the current work was to predict oxidative pathways of C-1305 that would reflect its phase I metabolism. The...
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Comprehensive two-dimensional gas chromatography and three-dimensional fluorometry for detection of volatile and bioactive substances in some berries
PublikacjaThe volatilefractionsofCapegooseberryandblueberryweredeterminedbyheadspacesolid-phase microextractioncoupledwithcomprehensivetwo-dimensionalgaschromatographywithtime-of-flight mass spectrometry(HS-SPME/GCGC-TOFMS).Thehighestamountofalcohol(51.8%),ester(32.8%)and carboxylicacid(6.9%)wasinblueberryincomparisonwithgooseberryandoppositelyketones(14.7%), aldehydes(9.9%)andterpenes(8%)werefoundingooseberry.Thebioactivecompoundsandantioxidant capacities...
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α-Pinene, 3-carene and d-limonene in indoor air of Polish apartments: The impact on air quality and human exposure
PublikacjaMonoterpenes are among most ubiquitous volatile organic compounds (VOCs) to be detected in indoor air. Since the quality of indoor air is considered important for inhabitants' well-being, the present study aimed at investigating impact of human activity on levels of selected monoterpenes applying passive sampling technique followed by thermal desorption and gas chromatography coupled mass spectrometry. One of the objectives of...
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Żółte barwniki organiczne w XIX-wiecznych farbach Jana Matejki - identyfikacja substancji barwiących, nośników, oraz wypełniaczy
PublikacjaNaturalne barwniki organiczne można znaleźć w wielu obiektach dziedzictwa kulturowego. Identyfikacja substancji barwiących obecnych w farbach historycznych dostarcza istotnych informacji dla wielu specjalistów zaangażowanych w naukę o sztuce. Identyfikacja składu farb pozwala na zastosowanie odpowiednich procedur dotyczących renowacji i konserwacji historycznych dzieł sztuki. Informacje te pozwalają na ich renowację zgodnie z decyzjami...
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Multi-state vibronic interactions in the fluorobenzene radical cation: The importance of quadratic coupling terms
PublikacjaThe multi-mode multi-state vibronic interactions in the set of X^2B_1 - D^2A_1 electronic states of the monofluoro benzene radical cation are investigated theoretically, based on a quadratic vibronic coupling approach. The underlying ionization potentials and coupling constants are obtained from ab initio coupled-cluster calculations. Previous investigations (relying on the linear coupling approach) are extended by including all...
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Isotope-labeled substances in analysis of persistent organicpollutants in environmental samples
PublikacjaUltratrace analysis of persistent organic pollutants (POPs) in environmental samples requires very sophisticated methods for both sample preparation and instrumental analysis. The complex matrix requires a multi-stage procedure. Each stage is a potential source of error, as a consequence of which the final result of analysis could be a source of misinformation rather than information. The individual stages and the procedure as...
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Cavitation wearing of the SUPERSTON alloy after laser treatment at cryogenic conditions
PublikacjaThe purpose of this paper is to demonstrate the method of laser remelting at cryogenic conditions of the SUPERSTON alloy and its influence on microstructure and cavitation wearing. The cavitation test was performed using the rotating disc facility in IPM PAN Gdansk. During the cavitation test, the mass loss of the material with different parameters of laser remelting was determined. Surface and cross-section microstructure of the...
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Dissociative multi-photon ionization of isolated uracil and uracil-adenine complexes
PublikacjaRecent multi-photon ionization (MPI) experiments on uracil revealed a fragment ion at m/z 84 that was proposed as a potential marker for ring opening in the electronically excited neutral molecule. The present MPI measurements on deuterated uracil identify the fragment as C3H4N2O+ (uracil+ less CO), a plausible dissociative ionization product from the theoretically predicted open-ring isomer. Equivalent measurements on thymine...
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Electron ionization induced fragmentation of fluorinated derivatives of bisphenols
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Ionization of tocopherols and tocotrienols in atmospheric pressure chemical ionization
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Low energy electron attachment to platinum(II) bromide (PtBr2)
PublikacjatDissociative electron attachment to PtBr2in the gas phase was studied in the low electron energy rangefrom zero up to 10 eV with an energy resolution of 150 meV. The experiments were carried out using ahemispherical electron monochromator coupled with a quadrupole mass spectrometer and pulse count-ing acquisition system. The only anion observed was Br−. This ion is formed at three resonance electronenergies: 0.4 eV, 1.2 eV and...
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Bi-dipole-bound anions
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Possible mechanisms for protecting NCα bonds in helical peptides from electron-capture (or transfer) dissociation
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Dissociation and fragmentation of furan by electron impact
PublikacjaDissociation and fragmentation processes that produce electronically excited atomic and molecular fragments, following electron impact excitation, have been studied in furan. The optical excitation technique has been employed over the electron incident energy range 15-95 eV. Formation of excited hydrogen atoms H(n) in the n = 4-10 states has been detected by observation of the Balmer series. The diatomic CH fragments are formed...