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Search results for: NITROUS OXIDE
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Status report on high temperature fuel cells in Poland – Recent advances and achievements
PublicationThe paper presents recent advances in Poland in the field of high temperature fuel cells. The achievements in the materials development, manufacturing of advanced cells, new fabrication techniques, modified electrodes and electrolytes and applications are presented. The work of the Polish teams active in the field of solid oxide fuel cells (SOFC) and molten carbonate fuel cell (MCFC) is presented and discussed. The review is oriented...
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Low-Coherence Interferometric Fiber-Optic Sensors with Potential Applications as Biosensors
PublicationFiber-optic Fabry-Pérot interferometers (FPI) can be applied as optical sensors, and excellent measurement sensitivity can be obtained by fine-tuning the interferometer design. In this work, we evaluate the ability of selected dielectric thin films to optimize the reflectivity of the Fabry-Pérot cavity. The spectral reflectance and transmittance of dielectric films made of titanium dioxide (TiO2) and aluminum oxide (Al2O3) with...
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Elicitation strategies for the improvement of essential oil content in Rhododendron tomentosum (Ledum palustre) bioreactor-grown microshoots
PublicationRhododendron tomentosum Harmaja, previously Ledum palustre L., is a fragrant plant growing in swampy areas, which is characterized by well-known repellent properties and the anti-arthritic potential. In the present study, R. tomentosum microshoots cultivated in RITA® bioreactor, providing the alternative, environment-independent source of the valuable essential oil, were treated for 7 days with copper and nickel salts, methyl jasmonate,...
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CGO FILMS ON YSZ ELECTROLYTE FABRICATED BY SPRAY PYROLYSIS FOR SOFC
PublicationINTRODUCTION Solid oxide fuel cells are one of the fastest developing energy converters. The advancement introduced by research community provides steady state progress is stability and performance of the fuel cells. Significant influence on the cell’s performance and stability is related to cell design. The simplest design just consists of an anode, a solid electrolyte and a cathode. However, in order to improve the properties,...
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Electronic conductivity in the SiO2-PbO-Fe2O3 glass containing magnetic nanostructures
PublicationThe linear impedance spectra of iron–silicate–lead glass samples were measured in the frequency range from 1 MHz to 1 MHz and in the temperature range from 153 K to 423 K. The structure was investigated by means of XRD and atomic force microscopy. Local electrical and magnetic properties of the samples were tested with the aid of electrostatic force microscopy (EFM) and magnetic force microscopy (MFM). The obtained results show...
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Multi-layered tissue head phantoms for noninvasive optical diagnostics
PublicationExtensive research in the area of optical sensing for medical diagnostics requires development of tissue phantoms with optical properties similar to those of living human tissues. Development and improvement of in vivo optical measurement systems requires the use of stable tissue phantoms with known characteristics, which are mainly used for calibration of such systems and testing their performance over time. Optical and mechanical...
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Treatment Wetland effluent quality improvement by usage sorbents of various origin
PublicationTWs are finding as low-cost and also effective system to treat domestic wastewater. The aim of this study is to find suitable adsorbing material for application in an additional treatment unit where treatment wetlands do not provide sufficient PO4 3- reduction level. Material M1 is a fine-grained by-product of thermal treatment of carbonate-siliceous rock (opoka) with high content of calcium carbonate CaCO3 in temperature 700°C....
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Unconditionally blue: Curing epoxy with polyethylene glycol (PEG) surface-functionalized Zn Fe3-O4 magnetic nanoparticles
PublicationNanoparticles govern early (chemical-controlled) and late (diffusion-controlled) stages of epoxy crosslinking, respectively. Surface functionalization of nanoparticles with macromolecules was recognized as an effective route to compensate for inadequate diffusion-controlled crosslinking. However, the effect of bulk composition amended with cations having catalytic effect towards epoxy ring opening has remained hitherto undescribed....
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INFLUENCE OF BISMUTH CONTENT ON COMPLEX IMMITTANCE CHARACTERISTICS OF PRESSURELESS SINTERED BiNbO4 CERAMICS
PublicationGoal of the present research was to study immittance properties of BiNbO4 ceramics fabricated by the solid state reaction route followed by pressureless sintering. Four sets of samples were examined, namely the one fabricated from the stoichiometric mixture of oxides, viz. Bi2O3 and Nb2O5 as well as the ones with an excess of 3%, 5% and 10% by mole of Bi2O3. The immittance properties were studied by impedance spectroscopy. Measurements...
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Enhanced photocatalytic activity of transparent carbon nanowall/TiO2 heterostructures
PublicationThe synthesis of novel tunable carbon-based nanostructure represented a pivotal point to enhance the efficiency of existing photocatalysts and to extend their applicability to a wider number of sustainable processes. In this letter, we describe a transparent photocatalytic heterostructure by growing boron-doped carbon nanowalls (B-CNWs) on quartz, followed by a simple TiO2 sol-gel deposition. The effect on the thickness and boron-doping...
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Mechanism of hopping conduction in Be–Fe–Al–Te–O semiconducting glasses and glass–ceramics
PublicationElectrical properties of beryllium-alumino-tellurite glasses and glass–ceramics doped with iron ions were studied using impedance spectroscopy. The conductivity was measured over a wide frequency range from 10 mHz to 1 MHz and the temperature range from 213 to 473 K. The D.C. conductivity values showed a correlation with the Fe-ion concentration and ratio of iron ions on different valence states in the samples. On the basis of...
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Effect of isovalent substitution on microstructure and phase transition of LaNb1−xMxO4 (M=Sb, V or Ta; x=0.05–0.3)
PublicationLaNb1−xMxO4 oxides with pentavalent elements of different ionic sizes (M=Sb, Ta and V, x=0.05–0.3) were synthesized by the solid state reaction method. Special interest was devoted to the antimony substituted lanthanum niobate which is a new material in this group. Rietveld analysis of the X-ray diffraction patterns was used to determine the influence of the material composition on unit cell parameters. On the basis of dilatometric...
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Structural and optical investigations of sol-gel derived lithium titanate thin films
Publicationin this paper structural and optical studies of lithium titanate (lto) thin films are presented. nanocrystalline thin films with 800 nm thickness were prepared by sol-gel method. to examine the influence of the annealing time on as-prepared films crystallization, the coatings were heated at 550 °c for 10, 20 and 80 h. structure of manufactured thin films was investigated using x-ray diffraction (xrd). the most visible lithium titanate...
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Nutraceutical value of persimmon (Diospyros kaki Thunb.) and its influence on some indices of atherosclerosis in an experiment on rats fed cholesterol-containing diet
PublicationThe nutraceutic value of persimmon (Diospyros kaki Thunb. cv. Triumph) and its influence on some indices of atherosclerosis were studied in vitro and in experiment on rats fed cholesterol-containing diet. It was found that persimmon possesses a high nutraceutical value: it contains soluble fibers, total polyphenols and phe - nolic acids. The content of dietary fiberwas 1.83 ± 0.11, 0.69 ± 0.07 and 1.14 ± 0.12 g/100 g fresh weight...
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Rheological, Mechanical, Microstructural and Radiation Shielding Properties of Cement Pastes Containing Magnetite (Fe3O4) Nanoparticles
PublicationThis work examines the influence of iron oxide nanoparticles (Fe3O4 NPs) on neutron and gamma-ray radiation shielding characteristics of Portland cement paste. Experimental evaluations were supplemented with theoretical studies using NXCom program. Portland cement pastes with 5, 10, 15, 20, and 30 wt% of nanomagnetite cement replacement were produced. Moreover, rheological, early strength development, compressive strength, and...
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Enhanced solar light photocatalytic performance of Fe-ZnO in the presence of H2O2, S2O82−, and HSO5− for degradation of chlorpyrifos from agricultural wastes: Toxicities investigation
PublicationThis study reported Fe doped zinc oxide (Fe-ZnO) synthesis to degrade chlorpyrifos (CPY), a highly toxic organophosphate pesticide and important sources of agricultural wastes. Fourier transform infrared, X-ray diffraction, scanning electron microscope, and energy-dispersive X-ray spectroscopic analyses showed successful formation of the Fe-ZnO with highly crystalline and amorphous nature. Water collected from agricultural wastes...
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Waste materials assessment for phosphorus adsorption toward sustainable application in circular economy
PublicationPhosphorus is the main determinant of nutrient enrichment in the water bodies. Many resources including nutrients may be shortly exhausted, assuming current consumption. This scenario leads to growing interest in resources recovery and/or reuse, which together with sustainable energy consumption and waste reduction are the main courses of the circular economy. Usage of coagulants in wastewater treatment plants (WWTP) does not allow...
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Embedded gas sensing setup for air samples analysis
PublicationThis paper describes a measurement setup (eNose) designed to analyze air samples containing various volatile organic compounds (VOCs). The setup utilizes a set of resistive gas sensors of divergent gas selectivity and sensitivity. Some of the applied sensors are commercially available and were proposed recently to reduce their consumed energy. The sensors detect various VOCs at sensitivities determined by metal oxide sensors’ technology...
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Electrically Conductive Carbon‐based (Bio)‐nanomaterials for Cardiac Tissue Engineering
PublicationA proper self-regenerating capability is lacking in human cardiac tissue which along with the alarming rate of deaths associated with cardiovascular disorders makes tissue engineering critical. Novel approaches are now being investigated in order to speedily overcome the challenges in this path. Tissue engineering has been revolutionized by the advent of nanomaterials, and later by the application of carbon-based nanomaterials...
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Effect of high loading of titanium dioxide particles on the morphology and selected properties of natural rubber-based composites
PublicationThe aim of this work was to prepare and characterize the natural rubber vulcanizates contained different amounts of titanium dioxide particles. At first rubber mixture was prepared using a laboratory two-roll mill and then samples were vulcanized in a hydraulic press. The formulation of rubber mixture and rubber-processing technique is based on our earlier investigations. Materials were obtained at the different titanium dioxide...
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Hybrid TiO2–Polyaniline Photocatalysts and their Application in Building Gypsum Plasters
PublicationHybrid materials of conjugated polymer and titanium(IV) oxide have attracted considerable attention concerning their potential benefits, including (i) ecient exploitation of visible light, (ii) a high adsorption capacity for organic contaminants, (iii) and eective charge carriers separation. The new class of the photocatalysts is promising for the removal of environmental pollutants in both aqueous and gaseous phases. For the first...
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Neurochemical changes underlying cognitive impairment in olfactory bulbectomized rats and the impact of the mGlu5-positive allosteric modulator CDPPB
PublicationThe olfactory bulbectomized (OBX) rat model is a well-established model of depression in which antidepressant drugs reverse deficits in the passive avoidance test 14 days after administration. Recently, the olfactory bulbectomized rat model has been proposed to be a model of Alzheimer’s disease (AD), and the available data indicate similarities between the changes that typically occur in AD and those observed in OBX animals. In...
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Emerging oxidized and defective phases in low-dimensional CrCl3
PublicationTwo-dimensional (2D) magnets such as chromium trihalides CrX3 (X ¼ I, Br, Cl) represent a frontier for spintronics applications and, in particular, CrCl3 has attracted research interest due its relative stability under ambient conditions without rapid degradation, as opposed to CrI3. Herein, mechanically exfoliated CrCl3 flakes are characterized at the atomic scale and the electronic structures of pristine, oxidized, and defective...
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Determination of Odor Air Quality Index (OAQII) Using Gas Sensor Matrix
PublicationThis article presents a new way to determine odor nuisance based on the proposed odor air quality index (OAQII), using an instrumental method. This indicator relates the most important odor features, such as intensity, hedonic tone and odor concentration. The research was conducted at the compost screening yard of the municipal treatment plant in Central Poland, on which a self-constructed gas sensor array was placed. It consisted...
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Anisotropic optical properties of few-layer black phosphorus coatings: from fundamental insights to opto-electrochemical sensor design
PublicationFew-layer black phosphorus (FLBP) is characterised by a tuneable bandgap, high carrier mobility and anisotropic optical properties. It therefore has the potential to find applications in electronics and photonics. FLBP oxidizes upon exposure to air, limiting its utility in devices and components. To address this issue, the thesis introduces methods and tools developed for studying FLBP's optical parameters, with a particular emphasis...
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Sonocatalytic degradation of Bisphenol A from aquatic matrices over Pd/CeO2 nanoparticles: Kinetics study, transformation products, and toxicity
PublicationIn this work, different ratios of palladium – cerium oxide (Pd/CeO2) catalyst were synthesized and characterized, while their sonocatalytic activity was evaluated for the degradation of the xenobiotic Bisphenol A (BPA) from aqueous solutions. Sonocatalytic activity expressed as BPA decomposition exhibited a volcano-type behavior in relation to the Pd loading, and the 0.25Pd/CeO2 catalyst characterized by the maximum Pd dispersion...
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Chitosan-based nanomaterials for removal of water pollutants
PublicationThe rise of micropollutants presents a significant threat to both the environment and human well-being, requiring effective strategies for their mitigation. Chitin serves as the precursor for chitosan, composed of two monomers featuring acetamido and amino groups. Chitosan possesses several noteworthy attributes, including its ability to bind water and fat, humidity content, solubility, consistent molecular weight, and various...
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UV-Vis-Induced Degradation of Phenol over Magnetic Photocatalysts Modified with Pt, Pd, Cu and Au Nanoparticles
PublicationThe combination of TiO2 photocatalyst and magnetic oxide nanoparticles enhances the separation and recoverable properties of nanosized TiO2 photocatalyst. Metal-modified (Me = Pd, Au, Pt, Cu) TiO2/SiO2@Fe3O4 nanocomposites were prepared by an ultrasonic-assisted sol-gel method. All prepared samples were characterized by X-ray powder diffraction (XRD) analysis, Brunauer-Emmett-Teller (BET) method, X-ray photoelectron spectroscopy...
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A critical review on electrospun membranes containing 2D materials for seawater desalination
PublicationElectrospun nanofibers are a cutting-edge class of membranes which have been applied in several molecular separations. These membranes can be well designed and tailored due to the versatility of the electrospinning process. Eminently, electrospun membranes, once implemented in membrane processes, are an alternative in removing salts and some other minerals from water, so-called desalination, for producing drinking water. Such membranes...
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Bioreactor shoot cultures of Rhododendron tomentosum (Ledum palustre) for a large-scale production of bioactive volatile compounds
PublicationRhododendron tomentosum Harmaja (Ledum palustre), a peat bog plant from Ericaceae family, has been used in traditional medicine as the anti-arthritis agent. Although modern researches confirm its anti-inflammatory properties, it remains threatened by habitat degradation and possibilities to collect this endangered species from its natural environment for further biological activity studies are limited. Therefore, R. tomentosum...
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Time window based features extraction from temperature modulated gas sensors for prediction of ammonia concentration
PublicationElectronic gas recognition systems, in literature commonly referred as electronic noses, enable the recognition of a type and a concentration of various volatile compounds. Typical electronic gas-analyzing device consists of four main elements, namely, gas delivery subsystem, an array of gas sensors, data acquisition and power supply circuits and data analysis software. The commercially available metal-oxide TGS sensors are widely...
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Electrochemically Obtained TiO2/CuxOy Nanotube Arrays Presenting a Photocatalytic Response in Processes of Pollutants Degradation and Bacteria Inactivation in Aqueous Phase
PublicationTiO2/CuxOy nanotube (NT) arrays were synthesized using the anodization method in the presence of ethylene glycol and different parameters applied. The presence, morphology, and chemical character of the obtained structures was characterized using a variety of methods—SEM (scanning electron microscopy), XPS (X-ray photoelectron spectroscopy), XRD (X-ray crystallography), PL (photoluminescence), and EDX (energy-dispersive X-ray spectroscopy)....
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Chemical variability of Rhododendron tomentosum (Ledum palustre) essential oils and their pro-apoptotic effect on lymphocytes and rheumatoid arthritis synoviocytes
PublicationRhododendron tomentosum (Ledum palustre) is an aromatic plant traditionally used for alleviating rheumatic complaints which makes it a potential candidate for a natural drug in rheumatoid arthritis (RA) treatment. However, the effects of plants’ volatiles on apoptosis of synovial fibroblasts and infiltrating leucocytes of RA synovia, have not been reported. Volatile fraction of R. tomentosum is chemically variable and chemotypes...
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Design, synthesis and high antitumor potential of new unsymmetrical bisacridine derivatives towards human solid tumors, specifically pancreatic cancers and their unique ability to stabilize DNA G-quadruplexes
PublicationNew promising unsymmetrical bisacridine derivatives (UAs), have been developed. Three groupsincluding 36 compounds were synthesized by the condensation of 4-nitro or 4-methylacridinone, imi-dazoacridinone and triazoloacridinone derivatives with 1-nitroacridine compounds linked with anaminoalkyl chain. Cytotoxicity screening revealed the high potency of these compounds against severaltumor cell lines. Particularly, imidazoacridinone-1-nitroacridine...
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Recovery and re-use of photovoltaic solar cells from crystalline silicon
PublicationCrystalline silicon-type PV modules consist, in order of mass, of glass, an aluminium frame, an EVA coating, solar cells, a terminal box, back film and tapping screws. From the economic point of view, pure silicon, recoverable from spent cells, is the most important material owing to its cost and shortage. For crystalline, silicon-based PV cells, the following chemical treatments were performed: removal of the metal coating, followed...
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WYBRANE WŁAŚCIWOŚCI FIZYCZNO-CHEMICZNE MIKROSFER I MOŻLIWOŚĆ ICH WYKORZYSTANIA W KOMPOZYTACH CEMENTOWYCH : The selected physico-chemical properties of microspheres and possibility of their use in cement composites
PublicationMicrospheres are formed during the mineral transformation stage in coal combustion. Their content in fly ashes from the combustion of different types of coals varies over a rather wide range from 0.01 to 4.8 wt.%. The microspheres have three main elements, silicon, aluminum and iron, the oxides of which account for about 89.0 wt.% of the material. Mineralogical analysis using XRD shows that microspheres mainly contain mullite and...
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A facile method for Tauc exponent and corresponding electronic transitions determination in semiconductors directly from UV–Vis spectroscopy data
PublicationIn this work, a facile method allowing for estimation of the exponent in the Tauc equation directly from the UV–vis spectra is presented. It is based on the Taylor expansion of the logarithmic version of the Tauc equation. The Tauc exponent is calculated from the tangent slope of the absorption data. Knowledge of this coefficient provides information about the optical transition types and is used as an input for the calculations...
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Proton-Electron Hole Interactions in Sr(Ti,Fe)O3−δ Mixed-Conducting Perovskites
PublicationOxides in which total electrical conductivity is determined by the partial conductivities of three types of charge carriers i.e. holes/ electrons, oxygen ions, and protons are key components of well-functioning proton ceramic fuel cells. Apart from electrochemical properties also easily modified microstructure is an important feature of the electrodes. In the paper, a group of SrTi1−xFexO3−δ (STF, x = 0.2–0.8) perovskites prepared...
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Comprehensive two-dimensional gas chromatography for determination of the terpenes profile of blue honeysuckle berries
PublicationTerpenes are the main group of secondary metabolites, which play essential role in human. The establishment of the terpenes profile of berries of different blue honeysuckle cultivars was achieved by headspace solid-phase microextraction coupled with comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (HS-SPME/GCGC-TOFMS). The berries were found to contain 44 terpenes identified by GCGC-TOFMS....
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Effect of cobalt addition on the corrosion behaviorof near equiatomic NiTi shape memory alloy in normal saline solution: electrochemical and XPS studies
PublicationThe electrochemical and corrosion (uniform and localized) behavior of a binary Ni52Ti48 shape memory alloy (SMA) and two ternary Ni52Ti48-xCox (x = 1.5 and 4.0 wt.%) SMAs were studied. Measurements were conducted in 0.9% NaCl solution at 37 oC employing various electrochemical methods. These include: linear polarization resistance (LPR), linear sweep voltammetry (LSV), chronoamperometry and dynamic electrochemical impedance spectroscopy...
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Dimethyl ether (DME) as potential environmental friendly fuel
PublicationIn recent years, there has been a growing interest in replacing petroleum fuels with so-called second generation environmental friendly fuels. Compared to traditional petroleum fuels dimethyl ether (DME) could be used as a clean high-efficiency compression ignition fuel with reduced particulate matter (PM), sulfur oxides (SOx), hydrocarbons (HC), carbon monoxide (CO) as well as combustion noise. Compared to some of the other leading...
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The influence of the Cu2O deposition method on the structure, morphology and photoresponse of the ordered TiO2NTs/Cu2O heterojunction
PublicationThe increased interest in highly ordered titania structures exhibiting tubular shape that could be directly formed onto the stable substrate is related with the intensive research on their modification enabling absorption of light within the wide solar spectrum and its further conversion into electric or chemical energy. Among others, formation of uniform 3D heterojunctions based on the TiO2 nanotubes attracts attention since porous...
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Cytocompatibility, antibacterial, and corrosion properties of chitosan/polymethacrylates and chitosan/poly(4‐vinylpyridine) smart coatings, electrophoretically deposited on nanosilver‐decorated titania nanotubes
PublicationThe development of novel implants subjected to surface modification to achieve high osteointegration properties at simultaneous antimicrobial activity is a highly current problem. This study involved different surface treatments of titanium surface, mainly by electrochemical oxidation to produce a nanotubular oxide layer (TNTs), a subsequent electrochemical reduction of silver nitrate and decoration of a nanotubular surface with...
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Performance and emission characteristics of diesel engines running on gaseous fuels in dual-fuel mode
PublicationConventional fossil fuels are being substituted with alternative green fuels because of their greenhouse gas emissions and pollution problems, which pose a severe threat to the environment. Several studies have reported the usage of biodiesel and gaseous fuels in both single and dual-fuel modes. Gaseous fuels such as producer gas, biogas, syngas, and hydrogen produced from renewable biomass could potentially be used along with...
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Pulsed Laser Deposition of Bismuth Vanadate Thin Films—The Effect of Oxygen Pressure on the Morphology, Composition, and Photoelectrochemical Performance
PublicationThin layers of bismuth vanadate were deposited using the pulsed laser deposition technique on commercially available FTO (fluorine-doped tin oxide) substrates. Films were sputtered from a sintered, monoclinic BiVO4 pellet, acting as the target, under various oxygen pressures (from 0.1 to 2 mbar), while the laser beam was perpendicular to the target surface and parallel to the FTO substrate. The oxygen pressure strongly affects...
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Recent Advances in Polymer Nanocomposites: Unveiling the Frontier of Shape Memory and Self-Healing Properties—A Comprehensive Review
PublicationShape memory and self-healing polymer nanocomposites have attracted considerable attention due to their modifiable properties and promising applications. The incorporation of nanomaterials (polypyrrole, carboxyl methyl cellulose, carbon nanotubes, titania nanotubes, graphene, graphene oxide, mesoporous silica) into these polymers has significantly enhanced their performance, opening up new avenues for diverse applications. The...
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Polymer and graphitic carbon nitride based nanohybrids for the photocatalytic degradation of pharmaceuticals in wastewater treatment – A review
PublicationPharmaceuticals, including antibiotics and anti-inflammatory drugs, have been frequently detected in water reservoirs, in concentrations ranging from ng/L to μg/L, owing to their wide use in treatment of human and animal disease. Their uncontrolled use results in their increased release into the environment which is harmful for humans, animals, aquatic life and aquatic system. To remove these pollutants from water bodies, various...
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From ashes to porous hierarchical nanocarbon electrode: Upcycling secondary waste materials through self-catalytic chemical vapour deposition
PublicationMetal and metal oxide particles are abundant in various ash-based wastes. Utilizing these as catalyst sources for the fabrication of carbon nanomaterials could present a valuable approach to reduce our reliance on non-renewable and costly catalyst sources, thereby facilitating large-scale nanomaterial production. In this context, secondary waste materials (SWMs) are by-products resulting from the (complete or partial) combustion...
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Emerging anticancer activity of candidal glucoseamine-6-phosphate synthase inhibitors upon nanoparticle-mediated delivery
PublicationNumerous glutamine analogues have been reported as irreversible inhibitors of the glucosamine-6-phosphate (GlcN-6-P) synthase in pathogenic Candida albicans in the last 3.5 decades. Among the reported inhibitors, the most effective N3-(4-methoxyfumaroyl)-L-2,3- diaminopropanoic acid (FMDP) has been extensively studied in order to develop its more active analogues. Several peptide−FMDP conjugates were tested to deliver FMDP to its...
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Immittance Studies of Bi6Fe2Ti3O18 Ceramics
PublicationResults of studies focusing on the electric behavior of Bi6Fe2Ti3O18 (BFTO) ceramics are reported. BFTO ceramics were fabricated by solid state reaction methods. The simple oxides Bi2O3, TiO2, and Fe2O3 were used as starting materials. Immittance spectroscopy was chosen as a method to characterize electric and dielectric properties of polycrystalline ceramics. The experimental data were measured in the frequency range D = (101–107)...