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Search results for: CHITOSAN HYDROGEL
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Aluminum-TiO2 NPs Composites as Non-precious Catalysts for Efficient Electrochemical Generation of Hydrogen
PublicationIn this paper, we demonstrated, for the first time, aluminum titania nanoparticle (Al-TiO2 NP) composites with variable amounts of TiO2 NPs as nonprecious active catalysts for the electrochemical generation of H2. These materials were synthesized by mixing desired amounts of hydrogen titanate nanotubes (TNTs), fabricated here by a cost-effective approach at moderate hydrothermal conditions, with aluminum powder (purity 99.7%; size...
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Review of hydrogen production technologies for automotive sector – thermodynamic analysis of energy and exergy losses
PublicationFew recent years has shown that hydrogen technology has a good chance to replace petroleum technology in automotive sector. However, hydrogen in pure form practically does not occur on Earth. That is why H2 form is used only as an energy carrier and it must be produced using another source of energy form water or hydrocarbon fuels. In this paper short overview of hydrogen production technology has been presented, with energy and...
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The effect of pre-hydrogen charging on corrosion behaviour of superduplex stainless steel welded joints
PublicationThe paper presents results of research undertaken to determine the influence of hydrogen on passivity and corrosion resistance of 2507 super duplex stainless steel welded joints. Butt welded joints were made with low heat input using flux corded arc welding (FCAW) method. Coupons of 5.0 x 5.0 mm were cut from the welded joints containing weld metal (WM), heat affected zone (HAZ) and parent metal (PM). Hydrogen was introduced...
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Nanosize effect of clay mineral nanoparticles on the drug diffusion processes in polyurethane nanocomposite hydrogels
PublicationStudies of swelling and release of naproxen sodium (NAP) solution by polyurethane nanocomposite hydrogels containing Cloisite® 30B (organically modified montmorillonite (OMMT)) have been performed. Polyurethane nanocomposite hydrogels are hybrid, nontoxic biomaterials with unique swelling and release properties in comparison with unmodified hydrogels. These features enable to use nanocomposite hydrogels as a modern wound dressing....
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Diffusible hydrogen management in underwater wet self-shielded flux cored arc welding
PublicationThis article reports the effect of underwater wet welding parameters and conditions on the diffusible hydrogen content in deposited metal for welding with a self-shielded flux cored wire. The diffusible hydrogen content in deposited metal was determined using the glycerin method according to the Plackett-Burman design determining the significance of the effect of the stick out length, welding current, arc voltage, travel speed...
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Bismuth-Doped Nano Zerovalent Iron: A Novel Catalyst for Chloramphenicol Degradation and Hydrogen Production
PublicationIn this study, we showed that doping bismuth (Bi) at the surface of Fe0 (Bi/Fe0, bimetallic iron system)—synthesized by a simple borohydride reduction method—can considerably accelerate the reductive degradation of chloramphenicol (CHP). At a reaction time of 12 min, 62, 68, 74, 95, and 82% degradation of CHP was achieved with Fe0, Bi/Fe0-1 [1% (w/w) of Bi], Bi/Fe0-3 [3% (w/w) of Bi], Bi/Fe0-5 [5% (w/w) of Bi], and Bi/Fe0-8 [8%...
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Effect of wet Hydrogen Sulfide on Carbon Steels Degradation in Refinery Based on Case Study
PublicationMaterial degradation caused by wet hydrogen sulfide (Wet H2S) is one of the major issues in refineries. Carbon steel is the main construction material used in refineries and is subjected not only to thickness loss but the hydrogen is the major concern. H2S leads to high atomic hydrogen penetration in steel which causes degradation in the form of blistering and/or cracking (HIC/SOHIC) and stress cracking in the area of welds and...
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Influence of conductive carbon and MnCo2O4 on morphological and electrical properties of hydrogels for electrochemical energy conversion
PublicationIn this work, a strategy for one-stage synthesis of polymer composites based on PNIPAAm hydrogel was presented. Both conductive particles in the form of conductive carbon black (cCB) and MnCo2O4 (MCO) spinel particles were suspended in the three-dimensional structure of the hydrogel. The MCO particles in the resulting hydrogel composite acted as an electrocatalyst in the oxygen evolution reaction. Morphological studies confirmed...
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Transport Mechanism of Paracetamol (Acetaminophen) in Polyurethane Nanocomposite Hydrogel Patches—Cloisite® 30B Influence on the Drug Release and Swelling Processes
PublicationThis article describes the swelling and release mechanisms of paracetamol in polyurethane nanocomposite hydrogels containing Cloisite® 30B (organically modified montmorillonite). The transport mechanism, swelling and release processes of the active substance in nanocomposite matrix were studied using gravimetric and UV-Vis spectroscopic methods. Swelling and release processes depend on the amount of clay nanoparticles in these...
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The effect of zinc oxide concentration on dry matter content of chitosan gels in carbonic acid.
Open Research DataThe dataset contains results determining the effect of zinc oxide addition at different concentrations on the dry matter content of chitosan gels in carbonic acid after a specified time. Zinc oxide at concentrations of 0.5 and 1% was added as a powder to a 1% solution of chitosan in carbonic acid and then homogenized. Differences were observed in the...
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A novel method for drop in drop edible oils encapsulation with chitosan using a coaxial technique
Open Research DataThe dataset present a novel one step method for oil encapsulation. In this coaxial system the oil constitutes the core of the capsule, while the chitosan solution is the polymer shell surrounding the core to provide separation of the core from the external environment. In comparison to other encapsulation methods, the presented technique is much simpler...
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Preparation, characterization and antimicrobial activity of polyvinyl alcohol/gum arabic/chitosan composite films incorporated with black pepper essential oil and ginger essential oil
PublicationIn this study, biocomposite films based on polyvinyl alcohol (PVA), gum arabic (GA) and chitosan (CS) incorporated with BPEO and GEO were fabricated by solvent casting method. FTIR, XRD, SEM and DSC were performed with mechanical and antimicrobial properties of PVA/GA/CS films with and without BPEO and GEO. The BPEO and GEO incorporated PVA/GA/CS films were significantly inhibited the growth of Bacillus cereus, Staphylococcus aureus,...
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Preparation, characterization and antimicrobial activity of polyvinyl alcohol/gum arabic/chitosan composite films incorporated with black pepper essential oil and ginger essential oil
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Electrostatic self-assembly approach in the deposition of bio-functional chitosan-based layers enriched with caffeic acid on Ti-6Al-7Nb alloys by alternate immersion
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Determination of changes in viscosity of hydrogel depending on shear rate (1.1 to 55 s-1).
Open Research DataThe rheological characteristics of hydrogel were made on the basis of a viscosity measurement using a Brookfield viscometer, using LV SC4 - 25 spindle and shear rates from 1.1 to 55 s-1.
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Determination of changes in viscosity of hydrogel depending on shear rate (1.7 to 34 s-1).
Open Research DataThe rheological characteristics of hydrogel were made on the basis of a viscosity measurement using a Brookfield viscometer, using LV SC4 - 27 spindle and shear rates from 1.7 to 34 s-1.
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Determination of changes in viscosity of hydrogel depending on shear rate (6.6 to 330 s-1).
Open Research DataThe rheological characteristics of hydrogel were made on the basis of a viscosity measurement using a Brookfield viscometer, using LV SC4 - 18 spindle and shear rates from 6.6 to 330 s-1.
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Raman data of deuterium and hydrogen grown boron-doped diamond
Open Research DataRaman spectra were recorded at room temperature using a micro-Raman spectrometer (Invia, Renishaw) equipped with an edge filter with different excitation wavelengths and lasers: UV λ = 325 nm (HeCd), blue λ = 488 nm (Ar+), green λ = 514 nm (Ar+), and IR λ = 785 nm (IR diode) and 50× microscope objective. To avoid sample heating, the radiation power...
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The effect of changes in the concentration of hydroxypropylcellulose on the rheological stability of pectin hydrogels.
Open Research DataThe rheological characteristics of the pectin hydrogel modified by hydroxypropylcellulose (added in a concetration range from 0.1 to 0.55% m/m) were made on the basis of the viscosity assessment using a Brookfield viscometer with an LV SC4 - 25 spindle and a shear rate of 0,22 s-1 in the temperature range 19-96 ° C.The data allowed selection of optimal...
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XPS data of deuterium and hydrogen grown boron-doped diamond
Open Research DataThe high-resolution C1s X-ray absorption spectra of BDD@H and BDD@D samples were measured using the facilities of the HE-SGM beamline (HE-SGM) at the BESSY II synchrotron radiation source of Helmholtz–Zentrum Berlin (HZB).[90] The measurements were carried out under ultra-high vacuum conditions: P ≈ 2×10−9 Torr at T = 300 K. The NEXAFS spectra were...
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Data on hydrogen migration in cation-induced dissociation of furan molecules
Open Research DataThe data include furan luminescence spectra obtained in collisions with H3+ and C+ cations and theoretical spectra of OH and CH radicals published in [1].
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TG-hydroxyl groups in TiO2-P25
Open Research DataTG analyses were performed for powdered TiO2 - commercial P25 sample, which was heat-treated from room temperature to 500 C in the nitrogen atmosphere. Mass loss at lower temperature such as 120 C was related to the physisorbed water, and that one occurring at 500 C to the chemisorbed hydroxyl groups.
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Generation of hydroxyl radicals in UV/TiO2 and UV/H2O2 systems
PublicationPrzeprowadzono badania efektywności generowania rodników hydroksylowych dla różnych warunkow fotokatalitycznego utleniania. Rodniki hydroksylowe oznaczano pośrednią metodą utleniania metanolu, w której następuje spektrofotometryczne oznaczenie powstałego formaldehydu po derywatyzacji z 2,4-dinitrofenylohydrazyną. Badania wykazały, że wzrost pH zwiększa efektywność generowania ·OH zarówno w układzie hetero- i homogenicznym....
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Unprecedented Adhesive Performance of Propylene-Based Hydroxyl Functionalized Terpolymers
PublicationThe synthesis of hydroxyl functionalized propylene-based terpolymers and their performance as hot melt adhesives were investigated. The products comprise uniformly distributed butyl and 4-hydroxyl-butyl branches along the polypropylene backbone. Despite the low hydroxyl-functionality level of ≤ 0.5 mol%, hydroxyl functionalized terpolymers show formidable adhesion to aluminum and steel providing an adhesive strength exceeding 16...
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Grzegorz Boczkaj dr hab. inż.
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Influence of High Temperature Oxidation on Hydrogen Absorption and Degradation of Zircaloy-2 and Zr 700 Alloys
PublicationThe present research was aimed at determining the effects of the oxide layers on hydrogen absorption, microstructure and mechanical properties of the Zircaloy- 2 and Zr 702 alloys. The oxidation was made at 350 °C, 700 °C and 900 °C for 10 to 30 min in laboratory air, followed by hydrogen cathodic charging for 72 h and annealing at 400 °C for 4 h. The slow strain rate tests were carried out on oxidized, charged and annealed specimens. The...
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Theoretical Investigation of the Electron-Transfer Dynamics and Photodegradation Pathways in a Hydrogen-Evolving Ruthenium-Palladium Photocatalyst
PublicationTime-dependent density functional theory calcula- tions combinedwith the Marcus theory of electron transfer (ET) were app lied on the molecular photocatalys t [(tbbpy) 2 Ru(tpph z)PdC l 2 ] 2 + in order to elucidate thelight-in- duced relaxation pathways populated upon excitation in the longer wavelength range of its absorption spectrum. The computational resultsshow that after the initial excitation, metal (Ru) to ligand (tpphz)chargetransfer...
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A giant 2-dimensional dielectric response in a compressed hydrogen-bonded hybrid organic–inorganic salt
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Role of nitrogen in optical and electrical band gaps of hydrogenated/hydrogen free carbon nitride film
PublicationWe report the optical and electrical band gap energy of amorphous hydrogenated carbon nitride (a-HCNx) and carbon nitride (a-CNx) as a function of nitrogen concentration (N/C). The optical band gap of a-HCNx and a-CNx films has been determined by means of Ellipsometry and UV-VIS. Both optical and electrical band gaps increase with elevated nitrogen concentration. Experimentally obtained electrical band gap is compared with the...
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Adaptive resolution simulation of liquid para-hydrogen: testing the robustness of the quantum-classical adaptive coupling
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Changes in the Mechanical Properties of Alginate-Gelatin Hydrogels with the Addition of Pygeum africanum with Potential Application in Urology
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AN EXPERIMENTAL STUDY OF THE PHOTOCATALYTIC HYDROGEN PRODUCTION IN THE LABORATORY-SCALE SET-UP DEPENDING ON THE PROCESS CONDITIONS
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A spectroscopic study into the decomposition process of titanium isopropoxide in the nitrogen–hydrogen 100kHz low-pressure plasma
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Peculiar hydrogen bonding behaviour of water molecules inside the aqueous nanochannels of lyotropic liquid crystals
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Resistance changes of carbon nanotubes decorated with platinum nanoparticles in the presence of hydrogen at different and constant concentrations
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Relationship between the static dipole polarizability and the static dipole magnetizability of the relativistic hydrogen-like atom
PublicationZnaleziono prostą liniową zależność pomiędzy statycznymi dipolowymi podatnościami: elektryczną i magnetyczną relatywistycznego atomu wodoropodobnego w stanie podstawowym.
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Supramolecular Assemblies of Hydrogen Bonded Carboxylic Acid Dimers Mediated by Phenyl-Pentafluorophenyl Stacking Interactions.
PublicationKwas pentafluorobenzoesowy tworzy heterodimery z kwasami benzoesowym i 2,4,6-trimetylobenzoesowym w wyniku oddziaływań typu pi-pi reszt fenylowych i pentafluorofenylowych. Otrzymane kokryształy wymienionych kwasów z 1,4-bisarylobutadiynami zawierały homodimery tworzone przez cząsteczki kwasów, pomiędzy którymi znajdowały się cząsteczki diarylodiacetylenów.
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Cubane Like Structure of a Silanethiol Primary Amine Assembly a Novel, Unusual Hydrogen Bond Pattern.
PublicationMetodą rentgenowskiej analizy strukturalnej wyznaczono struktury krystaliczne i cząsteczkowe trzech soli amoniowych: (t-BuO)3SiS(-)H3N(+)Bu-t, (i-PrO)3SiS(-)H3N(+)Bu-t i (t-BuO)3SiS(-)H3N(+)(CH2)2CH(CH3)2. Wszystkie trzy związki w ciele stałym tworzą tetramery w których atomy S i N wyznaczają w przybliżeniu naroża sześcianu. Trwałość tych agregatów, oprócz sił elektrostatycznego przyciągania, zapewnia sieć wiązań wodorowych N-H
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Determination of carbon monoxide, methane and carbon dioxide in refinery hydrogen gases and air by gas chromatography
PublicationW pracy przedstawiono metodę oznaczania śladowych zawartości tlenku węgla, metanu oraz dwutlenku węgla w rafineryjnych gazach wodorowych oraz powietrzu; granica oznaczalności metody wynosi odpowiednio 0,15, 0,15 oraz 0,20 mikro-gram/litr. Zaprezentowano w pracy prostą modyfikację chromatografu gazowego wyposażonego w detektor płomieniowo-jonizacyjny (FID). Zastosowano kolumnę typu PorapakQ, dodatkowo połączono szeregowo z krótką...
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Sulfate‐reducing bacteria‐assisted hydrogen‐induced stress cracking of 2205 duplex stainless steels
PublicationThe paper presents the results of a laboratory investigation of the microbiologically assisted hydrogen‐induced stress cracking (HISC) of 2,205 duplex stainless steel (DSS). The testing of susceptibility toward HISC was performed with two different methods. Precharged in sulfate‐reducing bacteria (SRB), inoculated medium samples were subjected to slow strain‐rate testing in artificial seawater. In situ constant load tests were...
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Exploring hydrogen energy systems: A comprehensive review of technologies, applications, prevailing trends, and associated challenges
PublicationExploring hydrogen energy and its associated technologies is a pivotal pathway towards achieving carbon neutrality. This article comprehensively reviews hydrogen production technologies, storage technologies, and end-use applications of hydrogen, based on the input energy source, operating conditions, conversion efficiency, energy density, and unit investment cost. The review also highlights the advantages, disadvantages, and technological readiness...
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Effect of underwater local cavity welding method conditions on diffusible hydrogen content in deposited metal
PublicationOne of the methods with great potential for applications in underwater repairs is local cavity welding. In local cavity method, cooling conditions and diffusible hydrogen amount in weld metal are nearly the same as those existed during welding in the air. This paper presents the results of literature survey and preliminary tests of the effect of local cavity welding conditions on diffusible hydrogen amount in a deposited metal....
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Interspecies distances between propionic acid degraders and methanogens in syntrophic consortia for optimal hydrogen transfer
PublicationA mixed culture from an anaerobic biowaste digester was enriched on propionate and used to investigate interspecies hydrogen transfer in dependence of spatial distances between propionate degraders and methanogens. From 20.3 mM propionate, 20.8 mM acetate and 15.5 mM methane were formed. Maximum specific propionate oxidation and methane formation rates were 49 and 23 mmol mg−1day−1, respectively. Propionate oxidation was inhibited by...
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Charge-assisted N(+)–H···(−)S hydrogen bonds in the crystal structure of selected diammonium thiophenolates.
PublicationNew salts of thiophenol with three flexible aliphatic diamines H2N(CH2)nNH2 (n = 2, 4 and 6) have been synthesized and characterized by elemental analyses, IR spectroscopy and X-ray crystallography in order to analyze their supramolecular architecture. Structural analyses indicate that in the crystals, proton transfer has occurred, with the –SH group giving (+)N–H···S(−) hydrogen bonding interaction. The structure of compound 1...
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THEORETICAL POTENTIAL OF HYDROGEN PRODUCTION FROM TEXTILES WASTES IN POMERANIAN REGION BY MEANS OF DARK FERMENTATION
PublicationModel has been developed for calculating theoretical mass of hydrogen produced from textile wastes by mean of dark fermentation. As vegetable fibres wastes were chosen two mostly used — cotton and linen (flax). As the synthethic carbohydrate rich fiber was chosen viscose. In the background there were introduced: problems of dark fermentation, characteristics of textile material structure. Additionally pathways of the process...
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Effect of Linear Energy and Microstructure on the Content of Residual Hydrogen in Welded Joints made of Superduplex Steels
PublicationThe article presents tests concerning the content of retained hydrogen present in FCAW and SAW welded joints made of superduplex steel. The use of various welding technologies resulted in the obtainment of welds having different microstructures and ferrite contents. Measurements of retained hydrogen present in joints (performed using the complete combustion method) revealed various contents of hydrogen in the base material and...
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Hydrogen migration in formation of NH(A3Π) radicals via superexcited states in photodissociation of isoxazole molecules
PublicationFormation of the excited NH(A 3Π) free radicals in the photodissociation of isoxazole (C3H3NO) molecules has been studied over the 14-22 eV energy range using photon-induced fluorescence spectroscopy. The NH(A 3Π) is produced through excitation of the isoxazole molecules into higher-lying superexcited states. Observation of the NH radical, which is not a structural unit of the isoxazole molecule, corroborates the hydrogen atom...
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Supramolecular Synthesis Based on a Combination of Se···N Secondary Bonding Interactions with Hydrogen and Halogen Bonds
PublicationExamination of the solid state structures of 2,1,3-benzoselenadiazole complexes with hydrogen or halogen bond donors has demonstrated that the 2,1,3-benzoselenadiazole molecules preferably form centrosymmetric dimers with use of [Se–N]2 supramolecular synthon, whereas the two remaining nitrogen atoms not involved in the [Se–N]2 supramolecular interactions can act as acceptors of hydrogen or halogen bonds. Cocrystallization of selenadiazoles...
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High Temperature Corrosion Evaluation of Porous Hastelloy X Alloy in Air and Humidified Hydrogen Atmospheres
PublicationIn this work a commercially available porous Hastelloy X alloy is characterized in terms of high temperature corrosion resistance. The alloy was oxidized in the temperature range from 500C to 900C in air and humidified hydrogen for 100 hours. Corrosion rates and porosity changes were measured. Microstructural characterization was performed using X-ray diffractometry and scanning electron microscopy. Results show that porous alloys...
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Hydrogen migration observed in fragmentation of the pyridine molecules in collisions with the H+, H2+, He+and He++cations
PublicationThe hydrogen atom migration preceding fragmentation of the pyridine molecules by the H+, H2+, He+ and He++ collisions has been investigated in the 5-2000 eV energy range. The pyridine molecule structure is lacking of the NH group, thus formation of the NH radicals is an evidence of the H atom relocation prior to the cation-induced fragmentation. The NH(A3Π) fragmentation yields measured by detecting its A3Π→X3Σ− fluorescence show...