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Study of the Effect of Filling Thermoplastic Medical Polyurethane with PVA, PLA or Diatomite on the Relaxation Times Distributions of 1H NMR
PublicationIn this work, to characterize the mobility of diferent sections of the macromole‑ cules of polyurethane (PUR), polyvinyl alcohol (PVA), and polylactic acid (PLA), as well as the density of crosslinks of the polymer chains when using fllers, we used the distributions of spin–lattice and spin–spin relaxation times for the protons. It is shown that the rigidity of the thermoplastic polymers depends on the sizes of the granules of...
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Gelatin-Modified Polyurethanes for Soft Tissue Scaffold
PublicationRecently, in the field of biomaterials, which are being designed for soft tissue scaffolding, is growing the interest of their modification with natural polymers. Synthetic polymers are often hard, not easy to process and they do not possess fine biodegradable profile. From the other hand natural polymers are biocompatible, but weak when used alone. The combination of natural and synthetic polymers gives the suitable properties...
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Electron-beam irradiation in TEM of hard-segment homopolymers and polyurethanes with different hard-segment content.
PublicationZbadano odporność na niszczenie radiacyjne w transmisyjnym mikroskopie elektronowym homopolimeru segmentów sztywnych i poliuretanów z różną zawartością segmentów sztywnych. Dokonano rejestracji morfologii tych polimerów w TEM w trakcie obserwacji w jasnym polu oraz selektywnej dyfrakcji elektronowej. Analizowano tkże te polimery w mikroskopie polaryzacyjnym przed i po obserwacjach w TEM. Potwierdzono doniesienia literatutowe o...
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Nanoemulsion Structural Design in Co-Encapsulation of Hybrid Multifunctional Agents: Influence of the Smart PLGA Polymers on the Nanosystem-Enhanced Delivery and Electro-Photodynamic Treatment
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<p>In vivo Studies on Pharmacokinetics, Toxicity and Immunogenicity of Polyelectrolyte Nanocapsules Functionalized with Two Different Polymers: Poly-L-Glutamic Acid or PEG</p>
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Coordination polymers based on octacyanometalates(iv,v) (M = Mo, W) and aliphatic polyamine copper(ii) tectons with [N3] donor atom sets
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Exploring thiophene-2-acetate and thiophene-3-acetate binding modes towards the molecular and supramolecular structures and photoluminescence properties of Pb(ii) polymers
PublicationTo evaluate the impact of the flexible positional isomeric ligands thiophene-2-acetate (2tpacCOO) andthiophene-3-acetate (3tpacCOO) on the construction and self-assembly process of Pb(II) polymers, twonovel compounds, [Pb(2tpacCOO)2(H2O)]n(1) and [Pb(3tpacCOO)2]n(2), were preparedviaanonhydro-thermal method with respect to green chemistry rules. The obtained polymers were fully characterized byelemental analysis, TG/DTG and PXRD,...
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Application potential of dummy molecularly imprinted polymers as solidphase extraction sorbents for determination of low-mass polybrominated diphenyl ethers in soil and sediment samples
PublicationDespite the introduction of restrictive regulations in the USA and the European Union, polybrominated diphenyl ethers (PBDEs) are still found in various types of environmental and biological samples at significant concentration levels. The presence of these persistent organic pollutants in the environment raises important issues because of their negative impact on immunological and neurological systems, and on the hormonal balances...
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Bioactive core material for porous load-bearing implants
PublicationSo far state of knowledge on biodegradable materials is reviewed. Among a variety of investigated materials, those composed of polymers and ceramics may be considered as only candidates for a core material in porous titanium alloy. The collagen and chitosan among natural polymers, polyhydroxy acids among synthetic polymers, and hydroxyapatite and tricalcium phosphate among ceramics are proposed for further research. Three essential...
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Evaluation of Low Temperature Properties of Rubberized Asphalt Mixtures
PublicationThe paper presents low-temperature test results of asphalt mixtures designed with use of bitumen modified by crumb rubber and also SBS polymer. Laboratory tests were conducted on two types of asphalt mixtures for wearing course – stone matrix asphalt (SMA 8) and porous asphalt (PA 8). This paper presents results of the following laboratory tests at low temperatures: TSRST test, three point bending creep test, fracture toughness...
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Magnetic Molecularly Imprinted Polymer Nanoparticles for Selective Extraction of Copper from Aqueous Solutions Prior to Its Flame Atomic Absorption Determination
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Magnetic molecularly imprinted polymer nanoparticles for selective extraction of copper from aqueous solutions prior to its flame atomic absorption determination
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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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Performance evaluation of an improved optical computed tomography polymer gel dosimeter system for 3D dose verification of static and dynamic phantom deliveries
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Dosimetry study of Re-188 liquid balloon for intravascular brachytherapy using polymer gel dosimeters and laser-beam optical CT scanner
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Unusual fluorescence anisotropy spectra of three-component donor-mediator-acceptor systems in uniaxially stretched polymer films in the presence of energy transfer
PublicationW pracy analizowano transfer energii w układzie donor-mediator-akceptor w osiowo rozciąganych foliach polimerowych. Stwierdzono, że informacja zawarta w orientacji wektora pola elektrycznego wiązki światła wzbudzającego układ jest zachowana po zajściu procesu transferu energii pomiędzy molekułami w foliach rozciąganych. Natomiast w foliach nierozciąganych fluorescencja mediatora i akceptora jest bardzo silnie zdepolaryzowana.
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Insightful Analysis of Phenomena Arising at the Metal|Polymer Interphase of Au-Ti Based Non-Enzymatic Glucose Sensitive Electrodes Covered by Nafion
PublicationThis paper focuses on the examination of glucose oxidation processes at an electrode material composed of gold nanoparticles embedded in a titanium template. Three dierent conditions were investigated: the chloride content in the electrolyte, its ionic conductivity and the presence of a Nafion coating. The impact of the provided environment on the oxidation reaction was evaluated by cyclic voltammetry (CV) and electrochemical impedance...
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Titania nanotubes infiltrated with conducting polymer PEDOT modified by Prussian Blue – a novel type of organic-inorganic heterojunction characterised with enhanced photoactivity.
PublicationA highly ordered p–n heterojunction was formed based on titania nanotubes containing a conducting polymer with Prussian blue matrix. The study demonstrates, for the first time, cases when a composite based on titania array scaffolding and Prussian blue embedded in PEDOT exhibits reversible FeII/FeIII redox activity. Highly enhanced photoactivity and capacitance of the obtained material are depicted in comparison to pristine titania....
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Synthesis and structural properties of (Y, Sr)(Ti, Fe, Nb)O3−δ perovskite nanoparticles fabricated by modified polymer precursor method
PublicationThe yttrium, iron and niobium doped-SrTiO3 powders have been successfully fabricated by a modified low–temperature synthesis method from a polymer complex. The usage of strontium hydroxide precursor instead of conventional strontium nitrate or strontium carbonate provides to the possibility of significant decrease of annealing temperature. It allows to prepare a material with sphere-shape grains of nanometric size (15–70 nm). The...
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The effect of transglutaminase or 1-ethyl-3-(3-dimethyl amino propyl) carbodimide (EDC) on the properties of two-component films fromfish-skin gelatin and other natural polymers
PublicationBadania dotyczą wpływu transglutaminazy na rozpuszczalność, właściwości mechaniczne oraz przepuszczalność pary wodnej dwuskładnikowych folii z żelatyny rybnej z dodatkiem kazeiny, białek soi, białek jaja kurzego lub pektyn. Dla porównania przeprowadzono równolegle modyfikacje chemiczne przy użyciu EDC.
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Wpływ syntetycznego polihydroksymaślanu na wybrane właściwosci nowych, otrzymanych z jego udziałem poliuretanów do zastosowań medycznych. cz II. Poliuretany z cykloalifatycznym diizocyjanianem w segmencie sztywnym. Polimery 56(1) 27-34, 2011
Publicationzsyntezowano poliuretany, w ltórych segmenty gietkie SG były zbudowane z telehelicznego, zakończonego obustronnie grupami -OH, ataktycznego polihydroksymaślanu (PHB). Wyniki DSC wskazują, że wprowadzenie PHB zaburza uporządkowanie w obrębie SG i sztywnych, zminejsza sie stopień krystaliczności, zwieksza sie nieco sorpcja wody. Test mikrobiologiczne wytworzonych PUR dowodzą skuteczności sterylizacji plazmą.
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Sztywne pianki poliuretanowe modyfikowane wybranymi nanonapełniaczami
PublicationZwiększona odporność nanokompozytów na działanie ognia polega na dobrym rozlokowaniu lamelarnych struktur oraz na ograniczeniu mobilności makromolekuł poprzez powstające mocne wiązanie polimer-nanonapełniacz, co utrudnia penetrację ognia do wnętrza materiału polimerowego. Badania przeprowadzone w Katedrze Technologii Polimerów Politechniki Gdańskiej miały na celu zbadanie wpływu wybranych nanonapełniaczy na bazie montmorylonitu...
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Study of the electrochemical stability of polypyrrole coating on iron in sodium salicylate aqueous solution
PublicationIn this work electrochemical stability of optimized PPy film on iron in aqueous solution of sodium salicylate is studied. The main drawback of conducting polymers is their possibility to undergo an irreversible degradation (overoxidation). The overoxidized polymers lose their properties, for example, conductivity and redox activity, what excludes them from some practical applications. This study demonstrates that lowering the concentration...
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Ocena właściwości niskotemperaturowych mieszanek mineralno-asfaltowych z asfaltem modyfikowanym SBS i gumą
PublicationW artykule przedstawiono wyniki badań przeprowadzonych w niskich temperaturach dla mieszanek mineralno-asfaltowych zaprojektowanych z użyciem asfaltów modyfikowanych miałem gumowym oraz polimerem SBS. Badania laboratoryjne zostały przeprowadzone dla dwóch rodzajów mieszanek mineralno-asfaltowych do warstwy ścieralnej – mastyksu grysowego (SMA 8) i asfaltu porowatego (PA 8). W niniejszym artykule przedstawiono wyniki następujących...
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Correction: Titania nanotubes infiltrated with the conducting polymer PEDOT modified by Prussian blue – a novel type of organic–inorganic heterojunction characterised with enhanced photoactivity
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Facilitated transport of Zn(II), Cd(II) and Pb(II) ions trough polymer inclusion membranes with calix[4]-crown-6 derivaties
PublicationBadano transport mieszaniny równomolowych ilości jonów Zn(II), Cd(II) i Pb(II)z wodnej fazy azotanowej (cMe=0,001M) przez polimerowe membrany inkluzyjne(PIM) zawierające pochodne kaliks[4]korony-6 jako nośniki jonów. Badany był wpływ różnych podstawników na wydajność procesu. Selektywność transportu przez membrany zawierające jonofory 4 i 5 malała w kolejności Pb(II), Zn(II), Cd(II), natomiast z jonoforem 3 Pb(II), Zn(II)Cd(II)....
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Determination of modifier contents in polymer-modified bitumens and in samples collected from the roads using high performance gel permeation/size exclusion chromatography
PublicationThis paper describes application of high performance gel permeation/size exclusion chromatography (HP-GPC/SEC) for the determination of content of polymer modifiers in modified road bitumens. The obtained results were compared with the measurements based on the procedure recommended by the American Association of State Highway and Transportation Officials, which employs Fourier transform mid-infrared spectroscopy (mid-IR FTIR)....
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Evolution of the nanostructure of Pt and Pt–Co polymer electrolyte membrane fuel cell electrocatalysts at successive degradation stages probed by X-ray photoemission
PublicationWe present a set of XPS (X-ray photoemission spectroscopy) measurements and detailed data-analysis of electrodes for polymer electrolyte membrane fuel cell (PEMFC) based on carbon supported catalysts (Pt and Pt–Co) subjected to a step-like potential cycling (accelerated degradation test). The results of the measurements complete and corroborate parallel TEM (transmission electron microscopy), XRD (X-ray diffraction) and XAS (X-ray...
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β-cyclodextrin-containing polymer based on renewable cellulose resources for effective removal of ionic and non-ionic toxic organic pollutants from water
PublicationA novel, bio-derived cyclodextrin-based trifunctional adsorbent has been successfully synthesized for efficient, rapid and simultaneous removal of a broad-spectrum of toxic ionic (anionic and cationic dyes) and non-ionic organic pollutants from water. The composition, morphology and the presence of functional groups in the obtained sorption material were characterized by elemental analysis, XRD, SEM, and FTIR spectroscopy. The...
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A procedure for the visualization of fingerprint traces on standard and thermal paper using the electron excitation energy of 1,8-diazafluoren-9- one aggregates in a polyvinylpyrrolidone polymer
PublicationThe scope of this study is a new procedure for visualizing dactyloscopic traces on an absorbent surface using a solution based on aggregates of 1,8-diazafluoren-9-one (DFO) in a polyvinylpyrrolidone polymer (PVP). An absorbent surface is defined as a plain or thermal paper, which is considered to be a difficult surface due to its varying chemical composition. In the case of the thermal paper surface, the procedure can be further...
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Studies on removal of Zn(II), Cd(II) and Pb(II) ions in polymer inclusion membrane transport with calix[4]-crown-6 derivatives
PublicationZbadano selektywność procesu wydzielania jonów cynku(II), kadmu(II) i ołowiu(II) z wodnych roztworów azotanowych zawierających równomolową mieszaninę tych trzech metali (cMe= 0,01 M) w procesie transportu przez polimerowe membrany inkluzyjne (PIM) przy użyciu w roli przenośników jonów pochodnych kaliks[4]-korony-6. Membrany typu PIM syntezowano z trójoctanu celulozy (nośnik), eteru o?nitrofenylopentylowego (pastyfikator) i pochodnych...
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PREPARATION AND CHARACTERIZATION OF CoFe2O4/TiO2-PANI HYBRID NANOCOMPOSITE WITH MAGNETIC AND PHOYOCATALYTIC ACTIVITY
PublicationHybrid nanocomposites consisting of inorganic component and organic conducting polymer are promising materials, which can be applied in heterogeneous photocatalysis. Titanium(IV) oxide is widely used photocatalysts due to its non-toxicity, low cost and chemical stability. The main disadvantage of TiO2 is low photocatalytic activity under visible light. Conducting polymers, also known as conjugated polymers are polymer materials...
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Electrochemically Induced Synthesis of Triphenylamine-based Polyhydrazones
PublicationTriphenylamine-based hydrazones were subjected to electropolymerization process that gave well conductive hydrazone based polymers. The first example of polyhydrazone formation during the electrochemical process was shown. The estimation of polymer structure was demonstrated using IR spectroelectrochemistry. The EPR spectroelectrochemistry allowed to explain why in some cases dimer couldn’t be formed. The results of electrochemical,...
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Evidence of Ligand Elasticity Occurring in Temperature-, Light-, and Pressure-Induced Spin Crossover in 1D Coordination Polymers [Fe(3ditz)3]X2(X = ClO4-, BF4-)
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The preparation and evaluation of core-shell magnetic dummy-template molecularly imprinted polymers for preliminary recognition of the low-mass polybrominated diphenyl ethers from aqueous solutions
PublicationThe design, preparation process, binding abilities, morphological characteristic and prospective field of application of dummy-template magnetic molecularly imprinted polymer (DMMIP) for preliminary recognition of the selected low-mass polybrominated diphenyl ethers (PBDE-47 and PBDE-99) from aquatic environment were investigated. The surface of iron oxide (Fe3O4) nanopowder (50-100 nm particles size) was modified with tetraethoxysilane...
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Dynamics of Chains as a Tool to Study Thermomechanical Properties of Proteins.
PublicationPolymer dynamics can be formulated on different levels of detail. One approach eliminates microscopic degrees of freedom and a polymer molecule is represented by a simplified structure—a chain. In the simplest case monomers of ideal chain have fixed length, and their orientation is independent of the orientations and positions of neighbouring monomers. This is reason that two monomers can co-exist at the same place. Ideal chain...
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Morphology and properties of recycled polyethylene/ground tyre rubber/thermoplastic poly(ester-urethane) blends
PublicationThe growing amount of plastics waste produced every year resulted in development of mechanical and chemical recycling methods of polymers and their blends or composites. From the environmental point of view, the possibility of plastics waste reusing and recycling is desirable. In this study three polymer blends were obtained with using recycled polyethylene (RPE), ground tyre rubber (GTR) and thermoplastic poly(ester-urethane)...
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Controllable Synthesis of 3D Hollow-Carbon-Spheres/Graphene-Flake Hybrid Nanostructures from Polymer Nanocomposite by Self-Assembly and Feasibility for Lithium-Ion Batteries
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Application of molecularly imprinted polymer pipette tip micro-solid phase extraction of nalidixic acid and acetaminophen from pills and seawater samples and their determination by spectrophotometry
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Ocena wybranych własności materiałowych polimerowej warstwy ślizgowej hydrodynamicznego łożyska wzdłużnego = An estimation of selected material properties of the hydrodynamic thrust bearing polymer lining
PublicationZaprezentowano metody pomiaru najważniejszych własności mechanicznych i cieplnych polimerowego pokrycia segmentowego łożyska wzdłużnego, do których zaliczyć należy moduł sprężystości wzdłużnej oraz współczynnik przewodności cieplnej materiału dodatkowym utrudnieniem planowanego zadania jest fakt, że próbka do badań dostępna będzie jedynie w formie wycinka z segmentu łożyskowego, z tego powodu nie jest możliwe zastosowanie ogólnie...
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Fabrication of a Molecularly Imprinted Polymer Adsorbent for Pipette Tip Micro Solid-phase Extraction of Levofloxacin from Aqueous Samples Prior to its Spectrophotometric Determination
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The comparison of the removal of copper(II) and zinc(II) ions from aqueous solution using 2,6-diaminopyridine in a polymer inclusion membrane and in a classic solvent extraction
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Simultaneous Recovery of Precious and Heavy Metal Ions from Waste Electrical and Electronic Equipment (WEEE) Using Polymer Films Containing Cyphos IL 101
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SU-FF-T-192: Complete 3D QA for Rapid Arc Using BANG Polymer Gel and OCTOPUS-IQ Fast Laser CT Scanner
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Application of response surface methodology to optimize pipette tip micro-solid phase extraction of dyes from seawater by molecularly imprinted polymer and their determination by HPLC
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MAX phase ternary carbide derived 2-D ceramic nanostructures [CDCN] as chemically interactive functional fillers for damage tolerant epoxy polymer nanocomposites
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The possibility of application of the potentiometric sensor with all-solid-state electrodes containing lipid-polymer membranes for classification of tested black leaf teas in terms of their quality
PublicationPotentiometric sensor with all-solid-state electrodes containing lipid-polymer membranes for a set of black leaf teas coming from four countries (China, India, Sri Lanka and Kenia) classification was applied. The tested tea samples were reassigned to quality classes marked with numbers I–V according to the information available. The sensor results of tea samples are presented in the form of radar charts. It was observed that, in...
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An unusual four-nuclear Pb(II)-pyrrole-2-carboxylato polymer: The effect of the lone pair and non-covalent interactions on the supramolecular assembly and fluorescence properties
PublicationThe reaction of Pb(NO3)2 with 1H-pyrrole-2-carboxylic acid (2prCOOH) leads to the formation of a new four-nuclear Pb(II) polymer, [Pb4(2prCOO)8(H2O)]n, which has been characterized by CHN, FT-IR, TG, PL and single-crystal X-ray diffraction methods. In view of the primary Pb–O bonds, Pb1 and Pb3 show hemidirected pentagonal pyramidal geometries, while Pb2 and Pb4 display hemidirected octahedral geometries. The topology of the strongest...
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Obtaining of Coumarone-Indene Resins Based on Light Fraction of Coal Tar. 4. Bitumen-Polymer Blends with Participation of Coumarone-Indene Resins with Epoxy Groups
PublicationUsing light fraction of coal tar (5.75 wt % of coumarone and 44.45 wt % of indene), glycidyl methacrylate and styrene, the coumarone-indene resin with epoxy groups (CIRE) has been synthesized. Monoperoxy derivative of diglycidyl ether Bisphenol A (PO) was used as an initiator. The possible formation of CIRE has been studied on the model systems consisting of PO, glycidyl methacrylate, indene or coumarone, or styrene, or mixture...
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Deposition and characterization of organic polymer thin films using a dielectric barrier discharge with different C2Hm/N2 (m = 2, 4, 6) gas mixtures
PublicationOrganic polymer thin films have been deposited on Si(100) and aluminum coated glass substrates by a dielectric barrier discharge (DBD) operated at medium pressure using different C2Hm/N2 (m = 2, 4, 6) gas mixtures. The deposited films were characterized by various spectroscopic techniques. Fourier transform infrared reflection absorption spectroscopy (FT-IRRAS) revealed the chemical functional groups present in the films. The surface...