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EN
The scientific aim of the paper is the characteristics of various types of nanoparticles, their physical and chemical parameters. In the article authors give examples of various nanoparticles used in reservoir engineering and EOR methods. The results of laboratory measurements of the impact of nanoparticles on the change of reservoir parameters and the increase of oil recovery of sandstones and carbonates are presented. In the article have been shown the possibilities of using nanotechnology, including the achievements of different authors. It presents a general literature review of modern research methodologies of nanoparticles in the global oil industry.
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In the present study silver nanoparticles were obtained using the ability of chitosan to form chelate compounds with metal ions and taking advantage of its reducing properties. The reduction process was conducted at the temperature 60°C or applying γ radiation from 60Co cobalt source. A preliminary characteristic which allows us to realize the size of formed silver nanoparticles was made on the basis of the measurements of UV absorption and dynamic light dispersion.
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Content available remote Effect of Surfactant Types on the Size of Tin Oxide Nanoparticles
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In this study, tin oxide (SnO₂) nanoparticles were synthesized by hydrothermal method in the presence of hydrazine and ammonia by adding surfactant for 12 h in a Teflon autoclave at 100°C reaction temperature. Tin(II) chloride hydrate as an inorganic precursor, hexadecyl trimethyl ammonium bromide (CTAB), and tetrapropyl ammonium bromide (TPAB) as cationic, and sodium dodecyl sulfonate (SDS) as anionic surfactants were used. The results showed that the size and shape of nanoparticles depended on the surfactant types. The nanoparticles sizes between 17.5 and 19.7 nm were obtained by changing types of surfactants. Synthesized tin oxide nanoparticles were characterized by field emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and the Fourier transform infrared spectroscopy.
EN
Silver particles having fine or ultrafine sizes are one of the fastest growing research interests with wide applications. Here we report the preparation method of silver modified paints which revealed antimicrobial activity against gram-negative bacteria Escherichia coli, gram-positive Staphylococcus aureus, yeast Saccharomyces cerevisiae and pathogenic fungi belonging to Candida family. In this work, we choose heptane and cyclohexane, as the oil phase for preparation nanometer sized metallic particles. We have also studied the effect of different silver precursors – silver nitrate, silver citrate and different surfactants: anionic AOT, non-ionic Triton X100, Span 80 and Tween 85 for stabilization of obtained silver colloids. UV-VIS spectrum contained a strong plasmon band near 410 nm, which confirmed silver ions reduction to Ag° in microemulsion system or aqueous phases. Prepared samples contained from 500 to 2000 ppm of silver. The diameter size of silver nanoparticles was in the range from 16 nm to 82 nm and were stable for 3 months without precipitation.
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Content available remote FMR study of agglomerated nanoparticles in a Fe3C/C system
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Three samples with various Fe3C/C ratios have been prepared by the carburisation of iron with ethylene or an ethylene-hydrogen mixture. Carburisation was controlled with thermogravimetry. After carburisation, the samples were characterized using XRD and scanning electron microscopy. XRD measurements have shown the presence of the Fe3C (cementite) phase only. The mean size of cementite crystallites estimated using Scherrer's equation was in the range of 40-46 nm. Ferromagnetic resonance (FMR) absorption signals were investigated at room temperature. In all samples an asymmetric, very broad, and intense FMR line shifted toward low magnetic field was recorded. The linewidth, intensity, and position of the resonance field depended strongly on carbon concentration. With increasing carbon concentration the linewidth and integrated intensities of the FMR spectra decreased, and the resonance line shifted towards higher magnetic fields. The separation of granules from each other by carbon could drastically influence the FMR absorption spectrum due to decreasing intergranular interaction with increasing carbon concentration.
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Content available Air quality filtration in vehicle cabins
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EN
A filter system is presented which allows the reduction of the concentration of ultrafine particles in vehicle cabins to very low levels. The original ventilation system is switched to the recirculation mode and all cabin intake air is supplied via a retro fitted filter system. Tests with a variety of different vehicles (from passenger cars to coaches) show the efficiency of the system. Number concentration of particles inside and outside a car, the nanoparticle filtration system, fllter-efficiency: transmission for the new filter and for the filter loaded to apressure drop of 2.9 mbar, setup of the filter with integrated prefilter for course particles and blower, prototype of the filter system, main filter, prefilter and blower are included the system operated by an external control box, containing the drive electronics for the blower and displays for filter pressure drop and time meter, filter pressure drop as function of operating time in a highly polluted road tunnel, a possible solution to mount the filter system, particle concentration inside and outside the car (passenger car), concentration drops to very low levels, particle concentration inside and outside a passenger car with the filter turned on, two nanocleaner filter systems mounted in a school bus, filter system for buses installed in the luggage compartment are presented in the paper.
EN
In future, more mobile devices with different frequencies will be used at the same time. Therefore, it is expected that the trouble caused by wave interference between devices will be further intensified. In order to prevent this trouble, investigation of selective frequency transmission or absorption material is required. In this paper, magnetic properties of nickel-zinc-copper ferrite nano powder was researched as wave absorber. (Nia-Znb)xCu1-xFe2O4(NZCF) nanoparticles were fabricated by the sol-gel method. The influence of copper substitution on lattice parameter change was analyzed by X-ray diffraction (XRD), particle size was analyzed by scanning electron microscopy (SEM), and Magnetic properties analyzed by vibrating sample magnetometer (VSM). The NZCF and Nickel-zinc ferrite (NZF) lattice parameter difference was 0.028 Å and particle size was calculated as 30 nm with the XRD peak. The VSM results of (Ni0.3-Zn0.3)0.6Cu1-0.6Fe2O4 annealed sample at 700°C for 3hous were 58.5 emu/g (Ms), 22.8 Oe (Hc). It was the most suitable magnetic properties for wave absorber in this investigation.
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Content available remote Restructurization of nanoaggregates in the impact breakage process
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The influence of spatial distribution of nanoparticles inside the aggregates on their impact breakage properties has been investigated. Modelling of mono- and polydispersional nanoaggregate impact breakage was performed for various structures and various sizes of nanoparticles, the interactions of which were determined by the Derjagin.Muller.Toropov model of adhesion and van der Waals theory, [2]. In the structures built of two types of particles, where those with smaller diameters are grouped in the form of an internal cluster (nucleus), the breakage process varies depending on the nucleus positions. In conclusion, we expect that control of nanoaggregate impact breakage is likely to provide structures with requested morphology.
PL
Badano wpływ rozkładu przestrzennego nanocząstek wewnątrz agregatu podczas zderzeń bezwładnościowych. Modelowanie rozpadu mono- i polidyspersyjnych nanoagregatów wykonano dla różnych struktur agregatu i rozmiarów cząstek związanych ze sobą siłami van der Waalsa według modelu Derjagina. Mullera.Toropova. Proces rozpadu struktur składających się z cząstek o różnych rozmiarach, z których mniejsze tworzą wewnętrzny zespół (jądro), zależy od pozycji jądra w agregacie. Wyniki badań wskazują również, że kontrolowany proces rozpadu w zderzeniach bezwładnościowych może prowadzić do otrzymywania agregatów o pożądanej morfologii.
EN
The effect of six SiO2 nanosized concentrations (0, 5, 20, 40, 60 and 80 mg L-1) and three seed prechilling treatments (control, seed prechilling before nano SiO2 treatments, treatments of seed with nano SiO2 before prechilling) on germination and seedling growth of tall wheatgrass (Agropyron elongatum L.) were studied. Results indicated that application of SiO2 nanoparticles significantly increased seed germination of tall wheatgrass from 58 percent in control group to 86.3 and 85.7 percent in 40 and 60 mg L-1, respectively. Applying SiO2 nanoparticles increased dry weight of shoot, root and seedling of tall wheatgrass. Increasing concentration of nanoparticle from 0 up to 40 mg L-1 increased seedling weight around 49 percent compared to the control, nevertheless decreased under 60 and 80 mg L-1 treatments. In conclusion, seed prechilling in combination with SiO2 nanoparticles largely broke the seed dormancy for A. elongatum.
EN
The effect of six SiO2 nanosized concentrations (0, 5, 20, 40, 60 and 80 mg L-1) and three seed prechilling treatments (control, seed prechilling before nano SiO2 treatments, treatments of seed with nano SiO2 before prechilling) on germination and seedling growth of tall wheatgrass (Agropyron elongatum L.) were studied. Results indicated that application of SiO2 nanoparticles significantly increased seed germination of tall wheatgrass from 58 percent in control group to 86.3 and 85.7 percent in 40 and 60 mg L-1, respectively. Applying SiO2 nanoparticles increased dry weight of shoot, root and seedling of tall wheatgrass. Increasing concentration of nanoparticle from 0 up to 40 mg L-1 increased seedling weight around 49 percent compared to the control, nevertheless decreased under 60 and 80 mg L-1 treatments. In conclusion, seed prechilling in combination with SiO2 nanoparticles largely broke the seed dormancy for A. elongatum.
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Rapid synthesis of gold nanoparticles (AuNPs) by pulsed electrodeposition was investigated in the non-aqueous electrolyte, 1-ethyl-3-methyl-imidazoliumbis(trifluoro- methanesulfonyl)imide ([EMIM]TFSI) with gold trichloride (AuCl3). To aid the dissolution of AuCl3, 1-ethyl-3-methyl-imidazolium chloride ([EMIM]Cl) was used as a supporting electrolyte in [EMIM]TFSI. Cyclicvoltammetry experiments revealed a cathodic reaction corresponding to the reduction of gold at −0.4 V vs. Pt-QRE. To confirmthe electrodeposition process, potentiostatic electrodeposition of gold in the non-aqueous electrolyte was conducted at −0.4 V for 1 h at room temperature. To synthesize AuNPs, pulsed electrodeposition was conducted with controlled duty factor, pulse duration, and overpotential. The composition, particle-size distribution, and morphology of the AuNPs were confirmed by field-emission scanning electron microscopy (FE-SEM), energy-dispersive spectroscopy (EDS), and transmission electron microscopy (TEM). The electrodeposited AuNPs were uniformly distributed on the platinum electrode surface without any impurities arising from the non-aqueous electrolyte. The size distribution of AuNPs could be also controlled by the electrodeposition conditions.
EN
Synthesis conditions influence on structure of FexCoyOz - nanoparticle in SiO2 - sol-gel coating is discussed. The samples are synthesized by hybrid sol - gel method including following stages: TEOS hydrolysis, introduction into sol of Co(NO3)2 . 6H20 and Fe(NO3)3 . 9H20, deposition of film-forming sol by spin-coating on silica substrate, heat treatment at the temperature from 200 up to 900 °C. The Synthesis conditions influence on a specific structural property of sol gel films is investigated by AFM.
EN
HNIW (2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane) is a family member of high-energy density cage nitramines which have so many versatile applications. In this paper, HNIW nanoparticles were prepared by the oil in water microemulsion route. The effects of various experimental parameters on this reaction were investigated using the Taguchi method. The effects of different variables: organic phase, water/organic phase (W1/W2), organic phase/ propanol (W3/W4) and HNIW weight percent, on the particle size of the HNIW were investigated at three distinct levels. Optimal conditions for obtaining HNIW nanoparticles were determined. Performing the process under the optimal conditions proposed by the Taguchi method leads to the production of HNIW nanoparticles with an average size of about 80 nm. The HNIW nanoparticles were characterized using Scanning Electron Microscopy (SEM), Dynamic Light Scattering (DLS), Differential Thermal Analysis (DTA) and X-Ray Diffraction (XRD).
EN
Cu-Ni composite nanoparticles were successfully synthesized by electrical explosion of wire (EEW) method. Cu-Ni alloy and twisted wires with various Ni contents were used as the feeding material for a 3 kV charging voltage EEW machine in an ethanol ambient chamber. The phase structure and magnetic properties of the as-fabricated samples were studied. It was established that the prepared powders after drying have a spherical form with the particle size is under 100 nm. XRD analysis indicated that the nanopowders consisted of binary Cu-Ni phases. Only pure phases of the intermetallic compound Cu-Ni (Cu0.81Ni0.19 and Cu3.8Ni) were observed in the XRD patterns of the samples. The synthesized intermetallic Cu-Ni alloy nanopowders reveal magnetic behaviors, however, the lower Ni content samples exhibited paramagnetic behaviors, meanwhile, the higher Ni content samples exposed ferromagnetic properties.
EN
The work discusses physicochemical phenomena related to interactions between the inhaled particles and the surface of pulmonary fluid which contains the lung surfactant. Dynamic surface phenomena which arise due to periodical variations of the interfacial area during breathing cycle are the extraordinary feature of this system and they are strictly related to the mechanics of ventilation and the pulmonary mass transfer processes. Presence of foreign material such as inhaled micro- and nanoparticles with different size, surface properties and morphology may alter these phenomena which may have some health consequences. This effect is discussed on two examples: mineral particles (CeO2) and carbonaceous particles emitted from diesel engine running on two different fuels. Two experimental methods of research in this field are presented: the Langmuir balance and the oscillating pendant drop. The results show the sensitivity of dynamic surface properties of the lung surfactant on exogenous materials which may be introduced to the respiratory system by inhalation of dusty air. Some physicochemical interpretation of these results is presented.
EN
The motion of submicron particles involves the deterministic terms resulting from the aerodynamic convection and/or electrostatic attraction, and the stochastic term from the thermal displacement of particles. The Langevin equation describes such behavior. The Brownian dynamics algorithm was used for integration of the Langevin equation for the calculation of the single fiber deposition efficiency. Additionally the deterministic and stochastic of the particle motion were derived, using the Lagrangian and Eulerian approaches of particle movement and balance, for the calculation of the single fiber deposition efficiency due to both mechanisms separately. Combination of the obtained results allows us for calculation of the coupling effect of inertia and interception with the Brownian diffusion in a form of correlation. The results of calculation show that the omitting of the coupling effect of particular mechanism and using the simple additive rule for determination of the single fiber deposition efficiency introduces significant error, especially for particles with diameter below 300 nm.
EN
The influence of ethanol on photocatalytic destruction of dyes (methylene blue, safranine, eosine, phenosafranine) in the presence of TiO2 powders and CdS nanoparticles in aqueous solutions was investigated. Anatase showed higher activity in water-ethanol solutions compared to rutile. The most active nanoparticles were CdS and CdS partially substituted by indium. It was established that ethanol increases the rate of photocatalytic destruction if it does not compete with the substrate for sorption centers on the photocatalyst surface.
PL
W pracy opisano otrzymywanie nanoproszków TiO2 o różnych wielkościach cząstek i różnym składzie fazowym (anataz/rutyl) metodą zol-żel. Analiza XRD wykazała, że TiO2 w zależności od temperatury kalcynacji krystalizuje w tetragonalnej strukturze anatazu (T ≤ 540 °C) lub w tetragonalnych strukturach anatazu i rutylu (T = 560 °C). Wzrost temperatury kalcynacji powoduje transformację anatazu do rutylu, aglomerację i spiekanie ziaren TiO2, czego konsekwencją jest wzrost cząstek i zmniejszanie powierzchni właściwej proszków.
EN
The paper describes a sol-gel method for preparing nanocrystaline powders with various particle size and phase composition (anatase/rutile). The XRD analysis showed that TiO2, depending on the calcination temperature, crystallizes in the tetragonal structure of anatase (T ≤ 540 C) or tetragonal structure of anatase and rutile (T = 560 °C). The increase in calcining temperature results in the transformation of anatase to rutile, particle agglomeration and sintering, entailing particle growth and reduction of specific surface area of the powders.
EN
The results of experimental studies on the effect of addition of nanoparticles on the atomization process in effervescent nozzles have been presented. It has been shown that the ratio of the gas flow rate to suspension of nanoparticles flow rate influences the spray quality in the same way as in air.water systems. The quality of the atomization process depends on the construction of the atomizer used. The correlations for the Sauter mean diameter have been proposed.
PL
Przedstawiono wyniki badań wpływu dodatku nanocząstek na proces rozpylania w dyszach pęcherzykowych. Wykazano, że wpływ stosunku masowego natężenia powietrza do natężenia przepływu wodnej zawiesiny nanocząstek na jakość rozpylania jest taki sam jak w przypadku układu powietrze.woda. Proces rozpylania zależy od konstrukcji dyszy rozpylającej. Zaproponowano równania korelacyjne opisujące wielkość kropli.
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W pracy przedstawiono wyniki badań nad syntezą ultra drobnokrystalicznych zawiesin bromku srebra, uzyskiwanych w postaci stężonych zoli stabilizowanych nadmiarem jonów bromkowych oraz żelatyną. Zbadano wpływ szybkości dozowania substratów do mieszaniny dyspersyjnej na wielkość powstających kryształów bromku srebra. Oszacowano również zmiany wielkości kryształów w czasie przechowywania zawiesin w formie żelu, w obniżonej temperaturze. Właściwości granulometryczne badano metodą turbidymetryczną dokonując pomiaru zmętnienia w czasie procesu krystalizacji oraz metodą stężeniową.
EN
This work present the results of research in ultra-fine crystals suspension of silver bromide crystals, which were received as high concentration sols stabilized by excess of bromide ions and gelatin. Relation between dosing rate of reactants to dispersion system and size of obtained silver bromide crystals was investigated. Alterations of crystals size during storing time as gel in decreased temperature, was estimated. Particle size distributions were examined by turbidity measurements using direct turbidity measurement technique in real time of crystallization process and by concentration method.
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