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EN
Purpose: The review focuses on chitosan nanoparticle synthesis and its biomedical applications. The review briefly explains the biomedical applications of antimicrobials, cancer therapy, gene therapy, and anti-ageing. Notably, the chitosan biological activity can be further increased by coating metal ions such as iron oxide nanoparticles, gold nanoparticles, etc. Design/methodology/approach: Chitosan is the N-acetyl derivative of chitin, which has the unique properties of biodegradability, non-toxicity, polycationic property and biocompatibility— no reports of ZnO sulphated chitosan nanoparticles being produced for antibacterial. We hope for the conduction of antibacterial research of ZnO sulphated chitosan nanoparticles. Findings: The study establishes that metal oxide nano-CH, characterised by an expanded size range beyond conventional parameters, exhibits a broad spectrum of biomedical applications. Its commendable biological attributes, encompassing biocompatibility, non-toxicity, and biodegradability, make it a vehicle for drug delivery in medicine. Research limitations/implications: Nanomedicine is an emerging branch of medicine that applies tools and the basis of nanotechnology for disease prevention, treatment and diagnosis. Moreover, it helps overcome conventional medicine's limitations, including adverse side effects, poor pharmacokinetics and lack of selectivity. Originality/value: Using chitosan extracted from marine waste presents economic advantages. Furthermore, when coated with metal oxide nanoparticles, it enhances biomedical efficacy. Chitosan is an effective drug delivery vehicle, and its theranostic applications are valuable in the biomedical sector.
EN
Phenol is present as a highly toxic pollutant in wastewater, and it has a dangerous impact on the environment. In the present research, the phenol removal from wastewater has been achieved using four treatment methods in a bubble column reactor (treatment by ozone only, using packed bubble column reactor with ozone, utilizing ozone with TiO2 NPs catalyst in the reactor without packing, and employing ozone with TiO2 NPs in the presence of packing). The effects of phenol concentration, ozone dosage, TiO2 NPs additions, and contact time on the phenol removal efficiency were determined. It was found that at a contact time of 30 min, the phenol removal was 60.4, 74.9, 86.0, and 100% for the first, second, third, and fourth methods, respectively. The results indicated that the phenol degradation method using catalytic ozonation in a packed bubble column with TiO2 NPs is the best treatment method. This study demonstrated the advantages of using packing materials in a bubble column reactor to enhance the mass transfer process in an ozonation reaction and then increase the phenol removal efficiency. Also, the presence of TiO2 NPs as a catalyst improves the ozonation process via the production of hydroxyl routs. Additionally, the reaction kinetics of ozonation reaction manifested that the first order model is more applicable for the reaction. Eventually, the packed bubble column reactor in the presence of TiO2 NPs catalyst provided a highperformance removal of phenol with a high economic feasibility.
EN
Purpose: Developing structural designs that offer superior vibration properties is still a major challenge, but they stay solid and lightweight simultaneously. Composite faces are frequently used in insulating constructions as an alternative to sheet metal roofs. Rubber overlays have been added to reduce waves' natural frequency and fade time. Design/methodology/approach: The mechanical properties and the natural frequency calculation of the materials that make up the composite structural panels designed for structural applications with the addition of rubber layers were studied in this study. Findings: The results showed the addition of rubber layers with SiO2 nanoparticles with a density of 1180 kg m3, and the optimal decrease (VF = 2.5%) is 38.5% in the natural frequency while at a density of 1210 kg/m3, it is 40.2% in the natural frequency. While the addition of rubber layers with Al2O3 nanoparticles shows a density of 1180 kg/m3, the optimum reduction (VF = 2.5%) is 41% in HF while at a density of 1210 kg/m3 36.8% in an NF 41% during a density of 1210 kg/m3 38.4%. Research limitations/implications: Certain hypotheses were used to apply Kirchhoff's theory to solve the mathematical model of the structure. Practical implications: The work was carried out on the faces of nanocomposites made of SiO2/epoxy and Al2O3/epoxy with different densities and polylactic acid core. The inclusion of nanoparticles as a percentage of the fraction size ranges from 0% to 2.50%. Originality/value: This study's results shed light on the fundamental behaviour of the components that make up the sandwich in the presence of rubber layers.
EN
The article presents methods of obtaining bioactive properties in the production of printed coatings The problems associated with the design of coatings are discussed and the currently known measures for combating pathogenic microorganisms are compared. Attention was also paid to special effects related to the durability of printed products with bioactive coatings.
EN
Purpose: The article presents the results of research on titanium dioxide synthesized by a sol-gel method that is an easy process enabling the control of the shape and size of particles The purpose of this article is to examine titanium dioxide nanoparticles and thin films deposited by an atomization method. Design/methodology/approach: Titanium dioxide sol was synthesized by using titanium isopropoxide as a precursor. Optical properties were measured by a UV-Vis spectrometer. Structural studies were performed by Raman spectroscopy. Qualitative analysis was performed by the EDS. Surface morphology of nanoparticles and thin films was performed by the SEM technique. Findings: The sol-gel method allows the formation of uniform nanoparticles and thin films of titanium dioxide. The atomization method is a successful method for the deposition of sol to the surface of substrates. Research limitations/implications: The next step in the research will be to investigate the obtained thin films in dye-sensitized solar cells as a semiconductive layer. Practical implications: Unique properties of produced titanium dioxide nanostructural materials have caused the interest in them in such fields as optoelectronics, photovoltaics, medicine and decorative coatings. Originality/value: Titanium dioxide thin films and nanoparticles were synthesized using the sol-gel method and then deposited by the atomization method.
PL
Celem artykułu jest określenie wpływu modyfikacji posadzki betonowej wybranymi nanocząstkami na jej parametry wytrzymałościowe. Przedstawiono wyniki badań wytrzymałości na zginanie i ściskanie posadzki wykonanej z zaprawy cementowej modyfikowanej nanocząsteczkami. Badania dotyczyły serii zapraw cementowych różniących się procentową zawartością nanocząstek w stosunku do masy cementu. Na podstawie przeprowadzonych badań wykazano, że wraz ze wzrostem zawartości nanocząstek w stosunku do masy cementu wytrzymałość zaprawy cementowej na zginanie maleje oraz że w zależności od rodzaju nanocząstki wytrzymałość na ściskanie zaprawy cementowej wzrasta, maleje lub pozostaje na podobnym poziomie.
EN
The purpose of the article is to describe the influence of modification of cement floor with selected nanoparticles on its strength parameters. Results of research of compressive strength and flexural strength made of cement mortar modified with addition of selected nanoparticles are described in the article. The research was performed for series of mortars differed in the percentage share content of nanoparticles in relation to cement mass. In the research it is reveal that nanoparticles influence mentioned above durability parameters of the floor. Based on the performed research it has been proved that with increasing content of nanoparticle flexural strength of the floor is decreasing. It has been also proved that depending on the used nanoparticle compressive strength is increasing, decreasing or is on similar level.
EN
Purpose: The article presents the results of research on ZnO nanopowder prepared using sol-gel method that is the easy process enabling us to control shape and size of particles The purpose of this article is to synthesized ZnO nanostructures by sol-gel method and characterized them for use in dye sensitized solar cells. Design/methodology/approach: Zinc oxide nanopowder was synthesized by using zinc acetate dehydrate as a precursor. The prepared nanopowder has been subjected to structural analysis using a transmission electron microscope (TEM). Scanning Electron Microscopic (SEM) images were taken with a Zeiss Supra 35. Qualitative studies of chemical composition were also performed using the Energy Dispersive Spectrometer (EDS). The structure of zinc oxide was investigated by X-ray crystallography The absorbance of zinc oxide layers with and without dye were measured by Thermo Scientific Evolution 220 spectrophotometer equipped with a xenon lamp in the wavelength range from 190 nm to 1100 nm. Findings: Sol-gel method allows the formation of uniform nanoparticles of zinc oxide. The nanoparticles have been successfully used in photoelectrode of dye sensitized solar cell. The light harvesting efficiency of the electrode it remains in a wide spectral range above 85%, which gives better results than in the case of titanium dioxide. Research limitations/implications: The next step in the research will be to investigate the ZnO/NiO composite on the properties of the photoelectrode of dye sensitized solar cell. Practical implications: he unique properties of produced ZnO nanostructural materials have caused their interest in such fields as medicine, transparent electronics and photovoltaics. Originality/value: The ZnO nanoparticles were prepared using sol-gel method and then effectively used in the photoanode of dye sensitized solar cell.
EN
Because of excellent properties, similar to natural bone minerals, and variety of possible biomedical applications, hydroxyapatite (HAp) is a valuable compound among the calcium phosphate salts. A number of synthesis routes for producing HAp powders have been reported. Despite this fact, it is important to develop new methods providing precise control over the reaction and having potential to scale-up. The main motivation for the current paper is a view of continuous synthesis methods toward medical application of produced hydroxyapatite, especially in the form of nanoparticles.
EN
Purpose: The purpose of this article is to synthesized NiO nanostructures by sol-gel method and characterized them for use in dye sensitized solar cells. For this purpose, a paste prepared from nanoparticles was prepared and screen printed on a glass substrate with the FTO layer. Design/methodology/approach: Nickel oxide nanoparticles was synthesized with participation of nickel (II) nitrate hexahydrate and citric acid. The prepared nanopowder has been subjected to structural analysis using a transmission electron microscope (TEM). Scanning Electron Microscopic (SEM) images were taken with a Zeiss Supra 35. Qualitative studies of chemical composition were also performed using the Energy Dispersive Spectrometer (EDS). The structure of nickel oxide was investigated by X-ray crystallography. An average crystallite size were calculated using Scherrer method and Williamson-Hall analysis. Light harvesting efficiency LHE was calculated from measured absorbance. Findings: The uniform nickel oxide nanoparticles with spherical shape were successfully produced by sol-gel method. The diameter of the as prepared nanoparticles does not exceed 25 nm which is confirmed by the XRD and TEM analysis. The light harvesting efficiency of the electrode in the entire studied range it’s over 90%. Therefore the NiO can be an attractive alternative to the most commonly used TiO2. Research limitations/implications: The next step in the research will be to investigate the ZnO/NiO composite on the properties of the photoelectrode of dye sensitized solar cell. Practical implications: The unique properties of produced NiO nanostructural materials have caused their interest in such fields as medicine, transparent electronics and photovoltaics. Originality/value: The NiO nanoparticles were prepared using sol-gel method and then effectively used in the photoanode of dye sensitized solar cell.
EN
The aim of this study was to compare the physico-chemical and biological properties of polymeric nanoparticles obtained from poly(DL-lactide-co-glycolide) (PLGA) with different ratios of monomers loaded with daunorubicin (DNR). Methods: DNR-loaded nanoparticles (NPs) were prepared with use of modified simultaneous double-emulsion solvent evaporation/diffusion technique. NPs were characterized using dynamic light scattering, atomic force microscopy, transmission electron microscopy, scanning electron microscopy, and differential scanning calorimetry and Fourier transform infrared spectroscopy. Results: NPs with DNR were differing in size and zeta potential, depending on the type of polymer. The data obtained show that total content of DNR correlates with the values of the binding constant of DNR with polymers. The release of DNR from NPs proceeds predominantly for polymers with lower binding constants. The in vitro study of NPs on the MCF-7 cells showed similar activity of particles and substances while for the anthracycline-resistant MCF-7Adr cells the cytotoxicity of the nanoparticles was 3 to 7 times higher depending on the type of copolymer. Conclusions: PLGA DNR-loaded nanoparticles can be used to overcome multidrug resistance (MDR) as well as for reducing the frequency of DNR reception due to the prolonged effect, which allows maintaining the concentration of the drug at the required level. The usefulness of binding constant calculations for obtaining nanoparticles with the maximum drug loading was proven. The rate of drug administration and the frequency of administration can be calculated based on the DNR release profiles and release parameters that depend on polymer type.
11
Content available remote Cheap nano-clay additive as a lubricating enhancer
EN
Cheap nano-clay (montmorillonite) was taken into consideration in this study as an additive to mineral oil to improve its lubricating properties. Mineral oils form the basis of speciality lubricants for food processing technology due to their biodegradability. In contrast to synthetic oils they are also less harmful. Literature indicates that nano-particles additives have a huge impact on lubricating properties. In this work wear scare diameter (WSD), friction coefficient and film thickness were studied. High frequency reciprocating rig (HFRR) was used to measure the said lubricating properties of prepared mixtures. Authors performed roughness measurements on sample plates after HFRR tests to study the relationship between WSD and Ra.
EN
In this article summary of all accomplishments of Nuclear and Medical Electronics Division in the field of Magnetic Nanoparticles Imaging. Magnetic Nanoparticles Imaging is a new tomographic and molecular imaging method that employs superparamagnetic nanoparticles as the tracer. This article includes the most importuned definition regarding this technique, its most interesting features, as well as report about research conducted in the Division in prospect to advance this imaging method in Poland.
PL
Artykuł ten podsumowuje dotychczasowe osiągnięcia Zakładu Elektroniki Jądrowej i Medycznej w dziedzinie obrazowania nanocząsteczek magnetycznych. Obrazowanie nanocząsteczek magnetycznych jest to nowa metoda obrazowania molekularnego i tomograficznego wykorzystująca jako znacznik nanocząsteczki superparamagnetyczne. W treści artykułu zawarto najważniejsze definicje dotyczące tego zagadnienia. Obecny stan rozwoju tej techniki oraz jej najbardziej interesujące właściwości, jak również opis prac badawczych podjętych przez Zespół w celu rozwoju tej metody obrazowania w Polsce.
EN
The assemblage of textiles and electronics in a single structure has led to the development of smart textiles for functional purposes and special products. Conductive yarn as a necessary component of smart textiles is being developed by a number of techniques. The objective of the current study was to impart conductivity to yarn by coating the silver and copper nanoparticles on the surface of multifilament polyester textile fibres. The surface morphology and electrical conductivity of the coated yarns were investigated. The wash ability of the conductive yarns developed was also studied. The yarns showed good retention of the nanoparticles, as proven by the very small loss of the conductivity of the material.
PL
Połączenie tekstyliów i elektroniki w jednej strukturze doprowadziło do rozwoju inteligentnych tekstyliów znajdujących zastosowanie w celach funkcjonalnych i produktach specjalnych. Przędza przewodząca, jako niezbędny składnik inteligentnych wyrobów włókienniczych, może być otrzymywana za pomocą szeregu różnych technik. Celem badania było nadanie przewodnictwa przędzy poliestrowej poprzez powlekanie jej nanocząsteczkami srebra i miedzi. Zbadano morfologię powierzchni i przewodnictwo elektryczne powleczonych przędz, a także ich odporność na pranie. Przędze wykazywały dobrą retencję nanocząstek, co potwierdzała bardzo mała utrata przewodności materiału.
EN
Functionalization of textile fabrics with metal oxide nanoparticles can be used to add antibacterial and moisture management properties to them. Current work focuses on the development of these properties on polyester/cotton woven fabrics by treating them with zinc oxide nanoparticles for workwear and sportswear applications. Zinc oxide nanoparticles, prepared by sol-gel method, were applied on fabric samples, which were then tested for antibacterial and moisture management properties using standard test methods AATCC 147 with Staphylococcus aureus and AATCC 195, respectively. It was found that application of ZnO nanoparticles improved both these properties with smaller particle imparting larger effects on both of them.
EN
Toxicological research on the influence of noxious nanoparticles on human health indicates the need to develop efficient protective devices. In particular, this concerns respiratory protective equipment employing filtration nonwovens. This paper presents a methodology for the improvement of the filtration efficiency of electret nonwovens against nanoparticles by enriching amorphous polycarbonate (PC) with additives of different electrostatic potentials. We introduced perlite granules (positive charge) and amber granules (negative charge) to the polymer stream in melt-blown technology. Filtration efficiency was assessed by a standard method using paraffin oil and sodium chloride aerosol, as well as by a non-standard method using NaCl nanoparticles. The experiments showed that strengthening the effects of electrostatic forces by the introduction of modifiers is a promising approach to improving the efficiency of electret nonwovens against nanoparticles.
EN
The nanocomposites based on water glass matrix were attempted in the study. Nanoparticles of ZnO, Al2O3 or MgO in organic solutions were applied into water glass matrix in the amounts of: 1.5; 3; 4 or 5 mas. %. Wettability of the quartz sad by the nanocomposites based on water glass matrix was determined by testing changes of the wetting angle θ in time τ for the system: quartz – binder in non-stationary state, by means of the device for measuring wetting angles. Wettability measurements were carried out under isothermal conditions at an ambient temperature (20 – 25 oC). The modification improves wettability of quartz matrix by water glass, which is effective in improving strength properties of hardened moulding sands. Out of the considered modifiers in colloidal solution of propyl alcohol water glass modified by MgO nanoparticles indicated the smallest values of the equilibrium wetting angle θr. This value was equal app. 11 degrees and was smaller no less than 40 degrees than θr value determined for not modified water glass. Viscosity η of nanocomposites based on water glass matrix was determined from the flow curve, it means from the empirically determined dependence of the shearing stress τ on shear rate γ: τ = f (γ) (1), by means of the rotational rheometer. Measurements were carried out at a constant temperature of 20 oC. The modification influences the binder viscosity. This influence is conditioned by: amount of the introduced modifier as well as dimensions and kinds of nanoparticles and organic solvents. The viscosity increase of the modified binder does not negatively influence its functional properties.
EN
The ceaseless progress of nanotechnology, observed in the last years, causes that nanomaterials are more and more often applied in several fields of industry, technique and medicine. E.g. silver nanoparticles are used in biomedicine for disinfection and polymer nanoparticles allow insulin transportation in pharmacology. New generation materials containing nanoparticles are also used in the chemical industry (their participation in the commercial market equals app. 53 %). Nanomaterials are used in electronics, among others for semiconductors production (e.g. for producing nanoink Ag, which conducts electric current). Nanomaterials, due to their special properties, are also used in the foundry industry in metallurgy (e.g. metal alloys with nanocrystalline precipitates), as well as in investment casting and in moulding and core sand technologies. Nanoparticles and containing them composites are applied in several technologies including foundry practice, automotive industry, medicine, dentistry etc. it is expected that their role and market share will be successively growing.
EN
The article describes the morphology of carbon-metal nanocomposites consisting of nanostructured rhenium permanently attached to carbon nanomaterials, in the form of single-walled (SWCNTs), double-walled (DWCNTs) or multi-walled carbon nanotubes (MWCNTs). Such nanocomposites are produced as a result of the high-temperature reduction of a rhenium precursor, including HReO4 or NH4ReO4, to metallic rhenium, deposited on the previously functionalised carbon nanomaterials in the form of nanoparticles whose size and dispersion are dependent upon the conditions of a technological process. Microscopic examinations carried out with scanning electron microscopy (SEM) and transmission electron microscopy (TEM) confirmed a differentiated structure of the presented nanocomposites depending on impregnation time in a rhenium precursor, which is one of the manufacturing steps of such materials. It has been demonstrated that longer impregnation time brings favourable results for material homogeneity in the whole volume. Moreover, the Raman spectroscopy results of functionalised carbon nanotubes and carbon nanotubes decorated with rhenium also has been presented.
PL
Zwiększające się wymagania odnośnie do właściwości zaczynu i kamienia cementowego sprawiają, iż konieczne jest poszukiwanie niekonwencjonalnych rozwiązań i materiałów, które zapewnią uzyskanie jak najlepszych efektów. Stosując odpowiednie ilości nanocząsteczek możliwe będzie zaprojektowanie zaczynu cementowego o dobrych parametrach reologicznych, dużej wytrzymałości, a równocześnie charakteryzującego się niską filtracją. W wyniku przeprowadzonych badań można zauważyć pozytywny wpływ dodatku nanotlenku krzemu, nanotlenku glinu i nanotlenku cynku na wytrzymałość mechaniczną oraz mikrostrukturę stwardniałych zaczynów cementowych z ich dodatkiem. Tak zmodyfikowane zaczyny charakteryzują się wysokimi wartościami wytrzymałości na ściskanie oraz wysokimi przyczepnościami do rur stalowych. Stwardniałe zaczyny posiadają zwartą mikrostrukturę o niskiej zawartości makroporów.
EN
Increasing requirements on the properties of slurry and set cement slurry enforce seeking unconventional solutions and materials that will ensure obtaining the best results. By using appropriate amount of nanoparticles will be possible to design the cement slurry with good rheological parameters, high compressive strength, and at the same time low filtration. As a result of the study can be seen the positive effect of the addition nanosilica, nanoaluminum and nano zinc oxide on strength and microstructure of hardened cement slurry. Such modified slurries exhibit high compressive strength and high adhesion for steel pipes. Hardened slurry has a compact microstructure with a low content of macropores.
EN
The recent advances and potential applications of nanoparticles and nanofibres for energy, water, food, biotechnology, the environment, and medicine have immensely conversed. The present review describes a ‘green’ method for the synthesis and stabilization of nanoparticles and ‘green electrospinning’ both using tree gums (arabic, tragacanth, karaya and kondagogu). Furthermore, this review focuses on the impending applications of both gum stabilized nanoparticles and functionalized membranes in remediation of toxic metals, radioactive effluents, and the adsorptive removal of nanoparticulates from aqueous environments as well as from industrial effluents. Besides, the antibacterial properties of gum derivatives, gum stabilized nanoparticles, and functionalized electrospun nanofibrous membranes will also be highlighted. The functionalities of nanofibrous membranes that can be enhanced by various plasma treatments (oxygen and methane, respectively) will also be emphasized.
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