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Search results for: hydrolytic degradation
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Possibility of exact determination of thermal and flow degradation symptoms in on-line power objects diagnostics
PublicationPrzedyskutowano problem dokładności tworzenia symptomów degradacji dotyczących sprawności urządzeń składowych dużych obiektów energetycznych. W referacie zajęto się szczególnie metodami tworzenia wzorców sprawnej pracy w przypadku określania sprawności w układzie on-line i porównano ją z określeniem w systemie off-line. Do odtwarzania stanu referencyjnego zastosowano sieć neuronową statystyczną (SSN, ang. ANN) o nieskokowych funkcjach...
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Influence of H2S on degradation of 9Cr-1Mo steel in advanced stage of metal dusting process
PublicationPrzedstawiono wyniki badań stali 9Cr-1Mo w zaawansowanym stadium procesu pylenia metalu po 10 latach eksploatacji w piecu rafineryjnej instalacji platformingu CCR, przeprowadzonych w celu podjęcia decyzji o dozowaniu związków siarki do wsadu instalacji. Na podstawie długotrwałej ekspozycji próbek stali w 600C w mieszaninie wodoru i siarkowodoru wykazano, że siarka może być powodem procesów wpływających niekorzystnie na stan materiału...
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Condition of Reinforced Concrete Structures and Their Degradation Mechanism at the Former Auschwitz Concentration and Extermination Camp
PublicationThis paper presents the results of investigations on reinforced concrete structures present in the former Auschwitz I and Auschwitz II-Birkenau concentration and extermination camp. Field inspection employing the non-destructive method of reinforcement potential measurement according to the ASTM-C 876–15 standard, followed by laboratory investigations performed on genuine historic reinforced concrete samples collected from the...
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Improved degradation of etodolac in the presence of core-shell ZnFe2O4/SiO2/TiO2 magnetic photocatalyst
PublicationIn the present study, susceptibility to photocatalytic degradation of etodolac, 1,8-diethyl-1,3,4,9 – tetrahydro pyran - [3,4-b] indole-1-acetic acid, which is a non-steroidal anti-inflammatory drug frequently detected in an aqueous environment, was for the first time investigated. The obtained p-type TiO2-based photocatalyst coupled with zinc ferrite nanoparticles in a core-shell structure improves the separation and recovery...
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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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Covalent DNA modification by products of myrosinase catalysed glucosinolate degradation in cell-free system
PublicationThe bioactive phytochemicals found in Brassica vegetables belonging to glucosinolates (GLS) and especially the products of their degradation isothiocyanates (ITC) and indoles are regarded as the most promising cancer chemopreventive compounds. These secondary metabolites constitute defence system repelling or preventing the development of agrophages attacking brassica plants. The antibiological properties of these compounds suggest...
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Monte Carlo simulations of the fracture resistance degradation of asphalt concrete subjected to environmental factors
PublicationThe paper presents the results of laboratory tests of SCB (semi-circular beam) samples of asphalt concrete, subjected to the destructive effect of water and frost as well as the aging processes. The determined values of material parameters show significant dispersions, which makes the design of mixtures difficult. Statistical analysis of the test results supplemented by computer simulations made with the use of the proprietary...
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New procedure for the examination of the degradation of volatile organonitrogen compounds during the treatment of industrial effluents
PublicationWe present a new procedure for the determination of 32 volatile organonitrogen compounds in samples of industrial effluents with a complex matrix. The procedure, based on dispersive liquid–liquid microex-traction followed by gas chromatography with nitrogen-phosphorus and mass spectrometric detection, wasoptimized and validated. Optimization of the extraction included the type of extraction and disperser sol-vent, disperser solvent...
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Impedance monitoring of corrosion degradation of plasma electrolytic oxidation coatings (PEO) on magnesium alloy
PublicationImpedance technique based on continuous multisinusoidal current perturbation was used to explain degradation process of plasma electrolytic oxidation coatings (PEO) on magnesium alloy. An obtained impedance spectrum was fitted by electrical equivalent circuit to describe properties of conversion layer on magnesium alloy. Additionally, galvanostatic mode maintained during experiment, with DC current equal to zero, allowed to achieve...
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Application of BN in Risk Diagnostics Arising from the Degree of Urban Regeneration Area Degradation
PublicationUrban regeneration as a complex project, generates many extremely specific threats affecting the increase of investment risk. Its unique nature causes that probability parameter, normally applied in the process of risk quantification, is extremely difficult to estimate. Due to lack of historical data urban regeneration related activities are therefore associated with uncertainty. According to the authors, a useful tool for resolving...
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Forced Degradation Studies of Ivabradine and In Silico Toxicology Predictions for Its New Designated Impurities
PublicationAll activities should aim to eliminate genotoxic impurities and/or protect the API against degradation. There is a necessity to monitor impurities from all classification groups, hence ivabradine forced degradation studies were performed. Ivabradine was proved to be quite durable active substance, but still new and with insufficient stability data. Increased temperature, acid, base, oxidation reagents and light were found to cause...
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ENVIRONMENTAL DEGRADATION OF DISSIMILAR AUSTENITIC 316L AND DUPLEX 2205 STAINLESS STEELS WELDED JOINTS
PublicationThe paper describes structure and properties of dissimilar stainless steels welded joints between duplex 2205 and austenitic 316L steels. Investigations were focused on environmentally assisted cracking of welded joints. The susceptibility to stress corrosion cracking (SCC) and hydrogen embrittlement was determined in slow strain rate tests (SSRT) with the strain rate of 2.2 × 10–6 s–1. Chloride-inducted SCC was determined in the...
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Degradation of electrical performance of a crystalline photovoltaic module due to dust deposition in northern Poland
PublicationThe reduction in power output caused by the accumulation of dust on the photovoltaic module surface is an important problem and should receive much more attention in the literature. This study was an evaluation of the performance degradation of crystalline photovoltaic modules due to natural and simulated dust deposition. Dust is created from powdered grains of sand and particles of different bodies. Dust originates from different...
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Degradation of stiffness of building columns exposed to bending and impact load during ground motions
PublicationThe safety of civil engineering structures under external loads, including ground motions, is one of the issues related to the idea of sustainable society. The earthquake-induced soft-storey failure is a typical type of damage observed in buildings due to seismic excitation. The failure of an intermediate soft storey of a structure results in large vertical impact loading acting on the lower floors due to the fall of the upper...
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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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Activated persulfate and peroxymonosulfate based advanced oxidation processes (AOPs) for antibiotics degradation – A review
PublicationSulfate radical AOPs (SR-AOP) were successfully utilized in degradation of antibiotics in water and wastewater treatment. The review discusses details on SR-AOPs mechanisms and applications for antibiotics degradation. The progress in this field was discussed, highlighting the most promising developments and remaining challenges. The applicability of SR-AOPs was summarized revealing the most susceptible and persistent to oxidation...
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Understanding the kinetics and atmospheric degradation mechanism of chlorotrifluoroethylene (CF2=CFCl) initiated by OH radicals
PublicationThe atmospheric degradation of chlorotrifluoroethylene (CTFE) by OH˙ was investigated using density functional theory (DFT). The potential energy surfaces were also defined in terms of single-point energies derived from the linked cluster CCSD(T) theory. With an energy barrier of −2.62 to −0.99 kcal mol−1 using the M06-2x method, the negative temperature dependence was determined. The OH˙ attack on Cα and Cβ atoms (labeled pathways...
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Degradation of bisphenol S – a contaminant of emerging concern - by synergistic ozone and percarbonate based AOP
PublicationDegradation of bisphenol S was studied using ozone activated by sodium percarbonate and the effectiveness of optimized process was compared with the peroxone process. The influence of several factors including sodium percarbonate concentration, ozone dose, pH, and water matrix were investigated. A synergetic coefficient of 3.84 was achieved for the combination of sodium percarbonate and ozone, confirming the effectiveness of this...
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Advanced Oxidation Processes for Degradation of Water Pollutants—Ambivalent Impact of Carbonate Species: A Review
PublicationAdvanced oxidation processes (AOPs) hold great promise in the removal of organic contaminants. Reactive oxygen species (ROS) produced in AOPs react with target pollutants to initially form several intermediate compounds that finally undergo complete mineralization. Such observations are reported, especially for laboratory-scale experiments performed in pure water. On the other hand, while considering real contaminated wastewater...
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Potential degradation of norfloxacin using UV-C/Fe2+/peroxides-based oxidative pathways
PublicationThe removal of norfloxacin (NOR), a widely used pharmaceutical and emerging water pollutant, was studied using UV-C and Fe2+ catalyzed peroxides-based oxidative processes (e.g., UV-C/Fe2+/H2O2, UV-C/Fe2+/S2O82− and UV-C/Fe2+/HSO5−) and compared with UV-C and UV-C/Fe2+. The UV-C and UV-C/Fe2+ degraded NOR to 38 and 55 %. However, use of peroxides, i.e., H2O2, S2O82−, HSO5− with UV-C and UV-C/Fe2+ promoted NOR %degradation to 75,...
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Epoxy/Ionic Liquid-Modified Mica Nanocomposites: Network Formation–Network Degradation Correlation
PublicationWe synthesized pristine mica (Mica) and N-octadecyl-N’-octadecyl imidazolium iodide (IM) modified mica (Mica-IM), characterized it, and applied it at 0.1–5.0 wt.% loading to prepare epoxy nanocomposites. Dynamic differential scanning calorimetry (DSC) was carried out for the analysis of the cure potential and kinetics of epoxy/Mica and epoxy/Mica-IM curing reaction with amine curing agents at low loading of 0.1 wt.% to avoid particle...
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Influence of Water-Induced Degradation of Polytetrafluoroethylene (PTFE)-Coated Woven Fabrics Mechanical Properties
PublicationThe impact of water-induced degradation on the mechanical properties of the chosen two PTFE-coated, glass threads woven fabrics is investigated in this paper. The paper begins with a survey of literature concerning the investigation and determination of coated woven fabric properties. The authors carried out the uniaxial tensile tests with an application of flat and curved grips to establish the proper values of the ultimate tensile...
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Thermal degradation kinetics of poly(propylene succinate) prepared with the use of natural origin monomers
PublicationLinear biobased polyester polyols were prepared with the use of succinic acid and 1,3-pro- panediol (both with natural origin). Tetraisopropyl orthotitanate (TPT) was used as a catalyst. In order to determine the effect of various synthesis temperature conditions on the thermal degradation kinet- ics, nine sequences of temperature conditions were used during two-step polycondensation reaction. Thermogravimetric analysis was conducted...
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The Effect of Long Term Service at Elevated Temperatures on Microstructure Degradation of Austenitic Reformer Tubes
PublicationThe paper analyses the relationship between an increase of the inner diameter of tubes made of Manaurite XM cast steel and transformations occurring in their microstructure due to long-lasting operation in methane reformer. Examinations included metallographic analysis with light microscope (LM), scanning electron microscope (SEM) and microanalysis of the chemical composition of precipitates (EDX). It was indicated that there is...
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Photocatalytic degradation of volatile and non volatile organics on titanium dioxyde particles in fluidized bed.
PublicationPrzeprowadzono degradację metyloetyloketonu w obecności dwutlenku tytanu jako fotokatalizatora. Badano wpływ początkowego stężenia substancji i stężenia fotokatalizatora na szybkość fotokatalitycznego rozkładu.
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Municipal soild waste settlement (MSWS) model with account for integrated creep and degradation processes.
PublicationModel oparto na superpozycji składowych osiadania zależnych od obciązenia i wpływu czasu, zgodnie z obserwowanym zachowaniem się odpadów komunalnych w warunkach polowych i laboratoryjnych. Składowe osiadania zależne od obciązenia, które przyrastają w miarę dokładania kolejnych warstw odpadów, oblicza się z uwzględnieniem modułu podatności zależnego od poziomu obciążenia. Składowe osiadania wynikające z upływu czasu obejmują osiadanie...
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The importance of degradation in the fate of selected organic compounds in the environment. Part II. Photodegradation and biodegradation
PublicationDegradacja jest naturalnym, wszechobecnym procesem rozkładu substancji organicznych obecnych w środowisku. Produkty degradacji lub pośrednie produkty rozkładu związków organicznych często wykazują inną toksyczność w stosunku do mikroorganizmów, zwierząt i ludzi niż związki wyjściowe. Procesy fotodegradacji i biodegradacji zachodzą zwykle jednocześnie. Fotodegradacja uznawana jest za wstępny proces, po którym następuje rozkład...
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The importance of degradation in the fate of selected organic compounds in the environment. Part. I. General considerations.
PublicationZwiązki organiczne, w zależności od elementu środowiska w jakim występują (gleba, osady denne, wody powierzzchniowe i gruntowe) mogą ulegać powolnym przemianom pod wpływem rozmaitych procesów fizycznych, chemicznych biologicznych czy też fotochemicznych. W pracy przedstawiono drogę degradacji wybranych trwałych zanieczyszczeń organicznych w różnych warunkach. Omówiono problem pojawiania się produktów pośrednich w czasie degradacji...
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Degradation and damage of advanced polymer composites due to environmental effects and low velocity impact
PublicationPrzedstawiono zagadnienie wpływu srodowiska wody oraz niskoenergetycznego udaru na właściwości mechaniczne laminatów epoksydowych wzmocnionych włóknami węglowymi, szklanymi, aramidowymi i hybrydowymi. Na tle krótkiego przeglądu literatury na dany temat przedstawiono oryginalne wyniki badań eksperymentalnych autorki.
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Application of artificial neural networks (ANN) as multiple degradation classifiers in thermal and flow diagnostics
PublicationPrzedyskutowano problem zwiększenia dokładności rozpoznawania wielokrotnych degradacji eksploatacyjnych urządzeń składowych dużych obiektów energetycznych. Zastosowani sieć neuronową (SSN) o skokowych funkcjach przejścia. Sprawdzono możliwości przyspieszenia treningu sieci neuronowych. Zastosowano modułową metodę budowy SSN, polegającą na dedykowaniu pojedynczej sieci do rozpoznawania tylko jednego typu degradacji.
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Niszczenie wodorowe stali o podwyższonej wytrzymałości = Hydrogen degradation of high-strength steels.
PublicationW artykule przedstawiono niszczenie wodorowe stali 18G2A i jej symulowanej strefy wpływu ciepła (SWC). Jako parametry niszczenia wodorowego wybrano względne wartości energii zniszczenia, czasu do pęknięcia, wydłużenia, przewężenia i wytrzymałości na rozciąganie. Parametry te wyznaczono w próbie odkształcania z małą prędkością na próbkach gładkich, okrągłych. Stwierdzono, że stal 18G2A w środowisku kwaśnym (0,1 N H2SO4) podczas...
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Prebiotic Potential of Oligosaccharides Obtained by Acid Hydrolysis of α-(1→3)-Glucan from Laetiporus sulphureus: A Pilot Study
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Potential DPP IV Inhibitory Peptides from Dry-Cured Pork Loins after Hydrolysis: An In Vitro and In Silico Study
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Partial inhibition of borohydride hydrolysis using porous activated carbon as an effective method to improve the electrocatalytic activity of the DBFC anode
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The Influence of COD Fraction Forms and Molecules Size on Hydrolysis Process Developed by Comparative OUR Studies in Activated Sludge Modelling
PublicationThe activated sludge models (ASMs) commonly used by the International Water Association (IWA) task group are based on chemical oxygen demand (COD) fractionations. However, the proper evaluation of COD fractions, which is crucial for modelling and especially oxygen uptake rate (OUR) predictions, is still under debate. The biodegradation of particulate COD is initiated by the hydrolysis process, which is an integral part of an ASM....
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Comparison and Optimization of Saccharification Conditions of Alkaline Pre-Treated Triticale Straw for Acid and Enzymatic Hydrolysis Followed by Ethanol Fermentation
PublicationThis paper concerns the comparison of the efficiency of two-stage hydrolysis processes, i.e., alkaline pre-treatment and acid hydrolysis, as well as alkaline pre-treatment followed by enzymatic hydrolysis, carried out in order to obtain reducing sugars from triticale straw. For each of the analyzed systems, the optimization of the processing conditions was carried out with respect to the glucose yield. For the alkaline pre-treatment,...
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A fast and convenient method for analysis of collagen hydrolysis products Szybka i dogodna metoda analizy produktów hydrolizy kolagenu
PublicationPolypeptides produced by hydrolysis of collagen from minced animal hide and skin scraps were studied by mass spectrometry (MS) in conjunction with electrophoresis to det. their mol. mass. The degree of peptides ionisation was ca 50+. This allowed for observation of the large polypeptide chains with mass analyzers with a relatively low m/z range. The electrospray and atm. pressure photoionization techniques were used. The polypeptide...
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Partial inhibition of borohydride hydrolysis using porous activated carbon as an effective method to improve the electrocatalytic activity of the DBFC anode
PublicationCarbon materials are commonly used catalyst supports in various types of fuel cells. Due to the possibility of designing their properties, they seem to be attractive and functional additives. In Direct Borohydride Fuel Cells (DBFCs), the electrooxidation reaction of borohydride competes with the undesirable hydrolysis reaction, therefore our work aimed to modify anodes based on a multi-component hydrogen storage alloy with a small...
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ICTP concentration in cervical-vaginal fluid as a potential marker of membrane collagen degradation before labor
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Phyto-mediated photocatalysis: a critical review of in-depth base to reactive radical generation for erythromycin degradation
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Enhanced sunlight photo-catalytic performances of ZnO/ZnNb2O6/Nb2O5 composites for organic pollutant degradation
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Continuous Monitoring of Thermooxidative Degradation Products of Polystyrene by Membrane Extraction with Sorbent Interface and Gas Chromatography
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Ag modified ZnO microsphere synthesis for efficient sonophotocatalytic degradation of organic pollutants and CO2 conversion
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The usefulness of ascorbic acid degradation to analyze the effectiveness of water filtration in household water filter jugs
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In-situ oxidative degradation of sulfamethoxazole by calcium peroxide/persulfate dual oxidant system in water and soil
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X-Ray Computer Tomography Study of Degradation of the Zircaloy-2 Tubes Oxidized at High Temperatures
PublicationThe investigations of high-temperature oxidation of zirconium alloys, applied for fuel pellets in nuclear power plants, are usually limited to oxidation kinetics, phase transformations and microstructural characterization. The purpose of this research was to characterize the degradation phenomena occurring within oxide layer and at the interface oxide/metal, on internal and external Zircaloy-2 tube...
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The effect of morphology and crystalline structure of Mo/MoO3 layers on photocatalytic degradation of water organic pollutants
PublicationMolybdenum oxide layers were formed by anodization of the Mo metallic foil in a water/ethylene glycol-based electrolyte containing fluoride ions. The as-prepared, amorphous samples were annealed in air at different temperatures in a range from 100 �C to 700 �C. The crystal phase and morphology of anodized and annealed MoO3 layers were investigated using X-ray diffraction, Raman spectroscopy, and scanning electron microscopy. The...
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Synergy between AgInS2 quantum dots and ZnO nanopyramids for photocatalytic hydrogen evolution and phenol degradation
PublicationDespite the unique properties of single semiconductor nanomaterials and quantum dots, poor photocatalytic activity has characterized them and the fabrication of nanocomposites has become necessary to enhance their photocatalytic performance. Thus, AgInS2 quantum dots (AIS QDs, 4.0±1.6 nm), have been successfully prepared and loaded onto ZnO nanopyramids (ZnO NPy). The effect of the nominal amount of AIS QDs decorating ZnO NPy on...
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The mechanical properties and bactericidal degradation effectiveness of tannic acid-based thin films for wound care
PublicationThe surface area is the most important aspect when considering the interactions between a material and the surrounding environment. Chitosan (CTS) and tannic acid (TA) were previously successfully tested by us to obtain thin films to serve as wound dressings or food packaging materials. However, surface properties as well as the antimicrobial activity of the material were not considered. They are important if the material is likely...
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Luminescence enhancement in nanocrystalline Eu2O3 nanorods – Microwave hydrothermal crystallization and thermal degradation of cubic phase
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