Artykuły w czasopismach: „Nanoparticle dispersions”

1

Metin, Cigdem, Roger T. Bonnecaze i Quoc P. Nguyen. "The Viscosity of Silica Nanoparticle Dispersions in Permeable Media". SPE Reservoir Evaluation & Engineering 16, nr 03 (24.07.2013): 327–32. http://dx.doi.org/10.2118/157056-pa.

Pełny tekst źródła

Streszczenie:

Summary The potential application of nanoparticle dispersions as formation-stimulation agents, contrast agents, or simply as tracers in the upstream oil and gas industry requires knowledge of the flow properties of these nanoparticles. The modeling of nanoparticle transport in hydrocarbon reservoirs requires a comprehensive understanding of the rheological behavior of these nanofluids. Silica nanoparticles have been commonly used because of their low-cost fabrication and cost-effective surface modification. The aqueous silica-nanoparticle dispersions show Newtonian behavior under steady shear measurements controlled by a rheometer, as discussed by Metin et al. (2011b). The viscosity of nanoparticle dispersions depends strongly on the particle concentration, and that this correlation can be depicted by a unified rheological model (Metin et al. 2011b). In addition, during flow in permeable media, the variation of shear associated with complex pore morphology and the interactions between the nanoparticles and tortuous flow channels can affect the viscosity of nanoparticle dispersion. The latter is particularly important if the concentration of nanoparticles in dispersion may change because of nanoparticle adsorption on mineral/fluid and oil/water interfaces or by mechanical trapping of nanoparticles. In this paper, the flow of silica-nanoparticle dispersions through different permeable media is investigated. The rheological behaviors of the dispersions are compared with those determined by use of a rheometer. We established a correlation between the nanoparticle concentration and dispersion viscosity in porous media for various nanoparticle sizes. The effects of pore structure and shear rate are also studied. We have confirmed that the concept of effective maximum packing fraction can be applied to describe the viscosity of aqueous nanoparticle dispersions in both bulk flow and flow in porous media with high permeability and regular pore structures, but not at low permeability because of mechanical trapping. Our work provides new insight to engineering nanoparticle rheology for subsurface applications.

Style APA, Harvard, Vancouver, ISO itp.

2

Bouaziz, Amina Manel, M. N. Bouaziz i A. Aziz. "Influences of Zero Mass Flux and Active Conditions on the Predictions of Double Dispersion and Double Diffusive Boundary Layer in Darcy/Non Darcy Nanofluid Flow". International Journal of Engineering Research in Africa 57 (9.11.2021): 49–65. http://dx.doi.org/10.4028/www.scientific.net/jera.57.49.

Pełny tekst źródła

Streszczenie:

Free convective of nanofluid inside dispersive porous medium adjacent to a vertical plate under the effects of the zero mass nanoparticles flux condition and the thermal and solutal dispersions is studied. Buongiorno's model revised is used considering Darcy and non Darcy laminar flows, and isothermal or convective flux outer the wall. Dimensionless governing equations formulated using velocity, temperature, concentration and nanoparticle volume fraction have been solved by finite difference method that implements the 3-stage Lobatto collocation formula. The numerical data obtained with semi or full dispersions cases are compared to predictions made using the non dispersive porous medium. Taking into account the dispersions, the influence of the zero mass nanoparticles flux condition is examined to test the validity of the control active nanoparticle assumption. It is found mainly that the thermal transfers can reach more than 100% in connection with the case where of a semi-dispersion of the porous medium is applied. Realistic condition, i.e. zero mass flux should be addressed for the heat transfer rate rather than the mass transfer rate, discovered markedly different to the active condition. This signifies the importance of considering the zero nanoparticles mass flux and dispersions in the performance characterization of nanofluid flow in porous media.

Style APA, Harvard, Vancouver, ISO itp.

3

López, Israel, i Idalia Gómez. "Microwave-Assisted Synthesis of Cadmium Sulfide Nanoparticles: Effect of Hydroxide Ion Concentration". MRS Proceedings 1617 (2013): 151–56. http://dx.doi.org/10.1557/opl.2013.1178.

Pełny tekst źródła

Streszczenie:

ABSTRACTCadmium sulfide nanoparticles were synthesized by a microwave-assisted route in aqueous dispersion. The cadmium sulfide nanoparticles showed an average diameter around 5 nm and a cubic phase corresponding to hawleyite. The aqueous dispersions of the nanoparticles were characterized by UV-Vis spectroscopy, luminescence analysis, transmission electron microscopy and X-ray diffraction. The addition of sodium hydroxide solutions at different concentrations causes a red-shift in the wavelength of the first excitonic absorption peak of the cadmium sulfide nanoparticles, indicating a reduction of the band gap energy. Besides, the intensity of the luminescence of the nanoparticle dispersions was increased. However, there is a threshold concentration of the hydroxide ion above which the precipitation of the cadmium sulfide nanoparticles occurs.

Style APA, Harvard, Vancouver, ISO itp.

4

Lorenzo, Arnaldo T., Ramakrishna Ponnapati, Tirtha Chatterjee i Ramanan Krishnamoorti. "Structural characterization of aqueous solution poly(oligo(ethylene oxide) monomethyl methacrylate)-grafted silica nanoparticles". Faraday Discussions 186 (2016): 311–24. http://dx.doi.org/10.1039/c5fd00137d.

Pełny tekst źródła

Streszczenie:

The structure of aqueous dispersions of poly(oligo(ethylene oxide) monomethyl methacrylate)-grafted silica nanoparticles was characterized using contrast variation small-angle neutron scattering studies. Modeling the low hybrid concentration dispersion scattering data using a fuzzy sphere and a polydisperse core–shell model, demonstrated that the polymer chains are highly swollen in the dispersions as compared to the dimensions of the free polymer chains in dilute solution. At higher hybrid concentrations, the dispersions were well described using a Percus–Yevick approximation to describe the structure factor. These structural characterization tools are excellent starting points for effective molecular level descriptors of dewetting and macroscopic phase transitions for polymer tethered hybrid nanoparticle systems.

Style APA, Harvard, Vancouver, ISO itp.

5

Peiris, T. A. Nirmal, Juan Benitez, Luke Sutherland, Manoj Sharma, Monika Michalska, Andrew D. Scully, Doojin Vak, Mei Gao, Hasitha C. Weerasinghe i Jacek Jasieniak. "A Stable Aqueous SnO2 Nanoparticle Dispersion for Roll-to-Roll Fabrication of Flexible Perovskite Solar Cells". Coatings 12, nr 12 (12.12.2022): 1948. http://dx.doi.org/10.3390/coatings12121948.

Pełny tekst źródła

Streszczenie:

Perovskite solar cells (PSCs) are attracting increasing commercial interest due to their potential as cost-effective, lightweight sources of solar energy. Low-cost, large-scale printing and coating processes can accelerate the development of PSCs from the laboratory to the industry. The present work demonstrates the use of microwave-assisted solvothermal processing as a new and efficient route for synthesizing crystalline SnO2 nanoparticle-based aqueous dispersions having a narrow particle size distribution. The SnO2 nanoparticles are analyzed in terms of their optical, structural, size, phase, and chemical properties. To validate the suitability of these dispersions for use in roll-to-roll (R2R) coating, they were applied as the electron-transport layer in PSCs, and their performance was compared with equivalent devices using a commercially available aqueous SnO2 colloidal ink. The devices were fabricated under ambient laboratory conditions, and all layers were deposited at less than 150 °C. The power conversion efficiency (PCE) of glass-based PSCs comprising a synthesized SnO2 nanoparticle dispersion displayed champion levels of 20.2% compared with 18.5% for the devices using commercial SnO2 inks. Flexible PSCs comprising an R2R-coated layer of synthesized SnO2 nanoparticle dispersion displayed a champion PCE of 17.0%.

Style APA, Harvard, Vancouver, ISO itp.

6

Bartucci, Roberta, Alex Z. van der Meer, Ykelien L. Boersma, Peter Olinga i Anna Salvati. "Nanoparticle-induced inflammation and fibrosis in ex vivo murine precision-cut liver slices and effects of nanoparticle exposure conditions". Archives of Toxicology 95, nr 4 (8.02.2021): 1267–85. http://dx.doi.org/10.1007/s00204-021-02992-7.

Pełny tekst źródła

Streszczenie:

AbstractChronic exposure and accumulation of persistent nanomaterials by cells have led to safety concerns on potential long-term effects induced by nanoparticles, including chronic inflammation and fibrosis. With this in mind, we used murine precision-cut liver tissue slices to test potential induction of inflammation and onset of fibrosis upon 72 h exposure to different nanomaterials (0–200 µg/ml). Tissue slices were chosen as an advanced ex vivo 3D model to better resemble the complexity of the in vivo tissue environment, with a focus on the liver where most nanomaterials accumulate. Effects on the onset of fibrosis and inflammation were investigated, with particular care in optimizing nanoparticle exposure conditions to tissue. Thus, we compared the effects induced on slices exposed to nanoparticles in the presence of excess free proteins (in situ), or after corona isolation. Slices exposed to daily-refreshed nanoparticle dispersions were used to test additional effects due to ageing of the dispersions. Exposure to amino-modified polystyrene nanoparticles in serum-free conditions led to strong inflammation, with stronger effects with daily-refreshed dispersions. Instead, no inflammation was observed when slices were exposed to the same nanoparticles in medium supplemented with serum to allow corona formation. Similarly, no clear signs of inflammation nor of onset of fibrosis were detected after exposure to silica, titania or carboxylated polystyrene in all conditions tested. Overall, these results show that liver slices can be used to test nanoparticle-induced inflammation in real tissue, and that the exposure conditions and ageing of the dispersions can strongly affect tissue responses to nanoparticles.

Style APA, Harvard, Vancouver, ISO itp.

7

Vippola, M., GCM Falck, HK Lindberg, S. Suhonen, E. Vanhala, H. Norppa, K. Savolainen, A. Tossavainen i T. Tuomi. "Preparation of nanoparticle dispersions for in-vitro toxicity testing". Human & Experimental Toxicology 28, nr 6-7 (czerwiec 2009): 377–85. http://dx.doi.org/10.1177/0960327109105158.

Pełny tekst źródła

Streszczenie:

Studies on potential toxicity of engineered nanoparticle (ENP) in biological systems require a proper and accurate particle characterization to ensure the reproducibility of the results and to understand biological effects of ENP. A full characterization of ENP should include various measurements such as particle size and size distribution, shape and morphology, crystallinity, composition, surface chemistry, and surface area of ENP. It is also important to characterize the state of ENP dispersions. In this study, four different ENPs, rutile and anatase titanium dioxides and short single- and multi-walled carbon nanotubes, were characterized in two dispersion media: bronchial epithelial growth medium, used for bronchial epithelial BEAS cells, and RPMI-1640 culture media with 10% of fetal calf serum (FCS) for human mesothelial (MeT-5A) cells. The purpose of this study was to determine the characteristics of ENPs and their dispersions as well as to compare dispersion additives suitable for toxicity tests and thus establish an appropriate way to prepare dispersions that performs well with the selected ENP. Dispersion additives studied in the media were bovine serum albumin (BSA) as a protein resource, dipalmitoyl phosphatidylcholine (DPPC) as a model lung surfactant, and combination of BSA and DPPC. Dispersions were characterized using optical microscopy and transmission electron microscopy. Our results showed that protein addition, BSA or FCS, in cell culture media generated small agglomerates of primary particles with narrow size variations and improved the stability of the dispersions and thus also the relevance of the in-vitro genotoxicity tests to be done.

Style APA, Harvard, Vancouver, ISO itp.

8

Shalaev, P. V., P. A. Monakhova i S. A. Tereshchenko. "Study of colloidal dispersions of gold nanorods using light scattering methods". Izvestiya Vysshikh Uchebnykh Zavedenii. Materialy Elektronnoi Tekhniki = Materials of Electronics Engineering 23, nr 2 (15.09.2020): 116–26. http://dx.doi.org/10.17073/1609-3577-2020-2-116-126.

Pełny tekst źródła

Streszczenie:

Five samples of colloidal dispersions of gold nanorods with various aspect ratio were studied using methods based on light scattering. Transmission electron microscopy was used as a reference method. The advantages and disadvantages of the dynamic light scattering and nanoparticle tracking analysis methods for determination of the geometric parameters of nanoparticles, their concentration, monodispersity, as well as for detection of large aggregates and quasispherical impurities were given. It was shown that the method of depolarized dynamic light scattering can be used for determination of the geometric parameters of liquid dispersions of colloidal gold nanorods. Moreover, it was found that the presence of large impurities or particle aggregates in the sample strongly affects the measurement results. The presence of large particles in the dispersion can be determined using dynamic light scattering or nanoparticle tracking analysis methods. The method of dynamic light scattering was also found to be more sensitive to the presence of even a small amount of large impurities or aggregates in the sample. The monodispersity of a liquid dispersion of nanorods can also be estimated by dynamic light scattering and nanoparticle tracking analysis methods, and, comparing to electron microscopy, the measurement results can be considered more statistically reliable due to the analysis of a larger number of particles. It was found that the increase of spherical particles concentration in the composite dispersion of nanospheres and nanorods leads to a decrease in the contribution of the rotational mode in the total scattering intensity. In addition, the concentration of quasispherical impurities in samples of liquid dispersions of colloidal gold nanorods was calculated based on measurements of the depolarization degree of scattered light.

Style APA, Harvard, Vancouver, ISO itp.

9

Zhu, Chunxiao, Hugh Daigle i Steven L. Bryant. "Paramagnetic nanoparticles as nuclear magnetic resonance contrast agents in sandstone: Importance of nanofluid-rock interactions". Interpretation 4, nr 2 (1.05.2016): SF55—SF65. http://dx.doi.org/10.1190/int-2015-0137.1.

Pełny tekst źródła

Streszczenie:

Nuclear magnetic resonance has been applied in well logging to investigate pore size distribution with high resolution and accuracy based on the relaxation time distribution. However, due to the heterogeneity of natural rock, pore surface relaxivity, which links relaxation time and pore size, varies within the pore system. To analyze and alter pore surface relaxivity, we saturated Boise sandstone cores with positively charged zirconia nanoparticle dispersions in which nanoparticles can be adsorbed onto the sandstone pore wall, while negatively charged zirconia nanoparticles dispersions were used as a control group to provide the baseline of nanoparticle retention due to nonelectrostatic attraction. We have performed core flushing with deionized water, pure acid, and alkali with different pH values; compared properties of zirconia nanoparticles before and after exposure to Boise sandstone; analyzed the portion of zirconia nanoparticles retained in the rock; altered pore surface relaxivity; and linked the adsorbed nanoparticle concentration on the pore surface to the modified surface relaxivity. Our work has indicated that after two pore volumes of core flooding, there was approximately 1% of negatively charged nanoparticles trapped in the Boise sandstone core, whereas approximately 8%–11% of positively charged nanoparticles was retained in the Boise sandstone cores. Our results indicated that besides van der Waals attraction, electrostatic attraction was the driving force for retention of nanoparticles with a positive surface charge in sandstone cores. The attachment of nanoparticles onto sandstone surfaces changed the mineral surface relaxivity. Exposure to acidic or strong alkaline conditions increased the Boise sandstone surface relaxivity. After contact with Boise sandstone, the nanoparticles themselves exhibited increased relaxivity due to interactions between nanoparticles dispersion and mineral surface under different pH conditions.

Style APA, Harvard, Vancouver, ISO itp.

10

Orlandi, Silvia, Erika Benini, Isabella Miglioli, Dean R. Evans, Victor Reshetnyak i Claudio Zannoni. "Doping liquid crystals with nanoparticles. A computer simulation of the effects of nanoparticle shape". Physical Chemistry Chemical Physics 18, nr 4 (2016): 2428–41. http://dx.doi.org/10.1039/c5cp05754j.

Pełny tekst źródła

Streszczenie:

Molecular-scale Monte Carlo simulations of liquid crystal-nanoparticle dispersions show the effect on the orientational order and on the clearing temperature of shape and concentration of the dopant nanoparticles.

Style APA, Harvard, Vancouver, ISO itp.

11

Marlow, Philipp, Felix Manger, Karen Fischer, Christian Sprau i Alexander Colsmann. "Eco-friendly fabrication of organic solar cells: electrostatic stabilization of surfactant-free organic nanoparticle dispersions by illumination". Nanoscale 14, nr 14 (2022): 5569–78. http://dx.doi.org/10.1039/d2nr00095d.

Pełny tekst źródła

Streszczenie:

Electrostatic effects promote the self-stabilization of surfactant-free P3HT and P3HT : ICBA nanoparticle dispersions in ethanol. Photoexcitation can control the stabilization of P3HT and other organic semiconductor nanoparticle dispersions.

Style APA, Harvard, Vancouver, ISO itp.

12

Lazauskas, Algirdas, Dalius Jucius, Linas Puodžiukynas, Asta Guobienė i Viktoras Grigaliūnas. "SiO2-Based Nanostructured Superhydrophobic Film with High Optical Transmittance". Coatings 10, nr 10 (29.09.2020): 934. http://dx.doi.org/10.3390/coatings10100934.

Pełny tekst źródła

Streszczenie:

Superhydrophobic and transparent films would be very useful in optoelectronic applications where non-wetting is desired. Herein, hexamethyldisilazane was used for functionalization of fumed SiO2 nanoparticles via silylation derivatization reaction. Modified fumed SiO2 nanoparticle dispersion was used for fabrication of SiO2-based nanostructured film via drop-casting method. This film exhibited a combination of high optical transmittance in the visible spectrum portion and superhydrophobicity (163° ± 1° and hysteresis as low as ~2°). This was possible to achieve due to the submicrometer-scale roughness (Rq = 252.7 nm) and branched network structure of the film surface with convenient surface chemistry of hydrophobic methyl groups. The method reported herein is not complicated, allows for obtaining large quantities of modified SiO2 nanoparticle dispersions and can be used in combination with other deposition methods.

Style APA, Harvard, Vancouver, ISO itp.

13

Galvão, Carolina, Luccas Sanches, Beatriz Mathiazzi, Rodrigo Ribeiro, Denise Petri i Ana Carmona-Ribeiro. "Antimicrobial Coatings from Hybrid Nanoparticles of Biocompatible and Antimicrobial Polymers". International Journal of Molecular Sciences 19, nr 10 (28.09.2018): 2965. http://dx.doi.org/10.3390/ijms19102965.

Pełny tekst źródła

Streszczenie:

Hybrid nanoparticles of poly(methylmethacrylate) synthesized in the presence of poly (diallyldimethyl ammonium) chloride by emulsion polymerization exhibited good colloidal stability, physical properties, and antimicrobial activity but their synthesis yielded poor conversion. Here we create antimicrobial coatings from casting and drying of the nanoparticles dispersions onto model surfaces such as those of silicon wafers, glass coverslips, or polystyrene sheets and optimize conversion using additional stabilizers such as cetyltrimethyl ammonium bromide, dioctadecyldimethyl ammonium bromide, or soybean lecithin during nanoparticles synthesis. Methodology included dynamic light scattering, determination of wettability, ellipsometry of spin-coated films, scanning electron microscopy, and determination of colony forming unities (log CFU/mL) of bacteria after 1 h interaction with the coatings. The additional lipids and surfactants indeed improved nanoparticle synthesis, substantially increasing the conversion rates by stabilizing the monomer droplets in dispersion during the polymerization. The coatings obtained by spin-coating or casting of the nanoparticles dispersions onto silicon wafers were hydrophilic with contact angles increasing with the amount of the cationic polymer in the nanoparticles. Against Escherichia coli and Staphylococcus aureus, bacteria cell counts were reduced by approximately 7 logs upon interaction with the coatings, revealing their potential for several biotechnological and biomedical applications.

Style APA, Harvard, Vancouver, ISO itp.

14

Zhang, Ren, Bongjoon Lee, Christopher M. Stafford, Jack F. Douglas, Andrey V. Dobrynin, Michael R. Bockstaller i Alamgir Karim. "Entropy-driven segregation of polymer-grafted nanoparticles under confinement". Proceedings of the National Academy of Sciences 114, nr 10 (22.02.2017): 2462–67. http://dx.doi.org/10.1073/pnas.1613828114.

Pełny tekst źródła

Streszczenie:

The modification of nanoparticles with polymer ligands has emerged as a versatile approach to control the interactions and organization of nanoparticles in polymer nanocomposite materials. Besides their technological significance, polymer-grafted nanoparticle (PGNP) dispersions have attracted interest as model systems to understand the role of entropy as a driving force for microstructure formation. For instance, densely and sparsely grafted nanoparticles show distinct dispersion and assembly behaviors within polymer matrices due to the entropy variation associated with conformational changes in brush and matrix chains. Here we demonstrate how this entropy change can be harnessed to drive PGNPs into spatially organized domain structures on submicrometer scale within topographically patterned thin films. This selective segregation of PGNPs is induced by the conformational entropy penalty arising from local perturbations of grafted and matrix chains under confinement. The efficiency of this particle segregation process within patterned mesa−trench films can be tuned by changing the relative entropic confinement effects on grafted and matrix chains. The versatility of topographic patterning, combined with the compatibility with a wide range of nanoparticle and polymeric materials, renders SCPINS (soft-confinement pattern-induced nanoparticle segregation) an attractive method for fabricating nanostructured hybrid films with potential applications in nanomaterial-based technologies.

Style APA, Harvard, Vancouver, ISO itp.

15

Nagal, Anubhav, i Rajeev K Singla. "Nanoparticles in Different Delivery Systems: A Brief Review". Indo Global Journal of Pharmaceutical Sciences 03, nr 02 (2013): 96–106. http://dx.doi.org/10.35652/igjps.2013.12.

Pełny tekst źródła

Streszczenie:

Nanoparticles are particulate dispersions or solid particles with a size in the range of 10-1000nm. The drug is dissolved, entrapped, encapsulated or attached to a nanoparticle matrix. Based upon the method of preparation, nanoparticles, nanospheres or nanocapsules can be obtained. This review article covered fundamentals of nanoparticles and their applications in various treatment strategies. © 2011 IGJPS. All rights reserved.

Style APA, Harvard, Vancouver, ISO itp.

16

Suvarli, Narmin, Max Frentzel, Jürgen Hubbuch, Iris Perner-Nochta i Michael Wörner. "Synthesis of Spherical Nanoparticle Hybrids via Aerosol Thiol-Ene Photopolymerization and Their Bioconjugation". Nanomaterials 12, nr 3 (8.02.2022): 577. http://dx.doi.org/10.3390/nano12030577.

Pełny tekst źródła

Streszczenie:

Hybrid nanomaterials possess the properties of both organic and inorganic components and find applications in various fields of research and technology. In this study, aerosol photopolymerization is used in combination with thiol-ene chemistry to produce silver poly(thio-ether) hybrid nanospheres. In aerosol photopolymerization, a spray solution of monomers is atomized, forming a droplet aerosol, which then polymerizes, producing spherical polymer nanoparticles. To produce silver poly(thio-ether) hybrids, silver nanoparticles were introduced to the spray solution. Diverse methods of stabilization were used to produce stable dispersions of silver nanoparticles to prevent their agglomeration before the photopolymerization process. Successfully stabilized silver nanoparticle dispersion in the spray solution subsequently formed nanocomposites with non-agglomerated silver nanoparticles inside the polymer matrix. Nanocomposite particles were analyzed via scanning and transmission electron microscopy to study the degree of agglomeration of silver nanoparticles and their location inside the polymer spheres. The nanoparticle hybrids were then introduced onto various biofunctionalization reactions. A two-step bioconjugation process was developed involving the hybrid nanoparticles: (1) conjugation of (biotin)-maleimide to thiol-groups on the polymer network of the hybrids, and (2) biotin-streptavidin binding. The biofunctionalization with gold-nanoparticle-conjugates was carried out to confirm the reactivity of -SH groups on each conjugation step. Fluorescence-labeled biomolecules were conjugated to the spherical nanoparticle hybrids (applying the two-step bioconjugation process) verified by Fluorescence Spectroscopy and Fluorescence Microscopy. The presented research offers an effective method of synthesis of smart systems that can further be used in biosensors and various other biomedical applications.

Style APA, Harvard, Vancouver, ISO itp.

17

Röhl, Susanne, Lena Hohl, Sebastian Stock, Manlin Zhan, Tobias Kopf, Regine von Klitzing i Matthias Kraume. "Application of Population Balance Models in Particle-Stabilized Dispersions". Nanomaterials 13, nr 4 (11.02.2023): 698. http://dx.doi.org/10.3390/nano13040698.

Pełny tekst źródła

Streszczenie:

In this study, a first approach to model drop size distributions in agitated nanoparticle-stabilized liquid/liquid systems with population balance equations is presented. Established coalescence efficiency models fail to predict the effect of steric hindrance of nanoparticles at the liquid/liquid interface during the film drainage process. A novel modified coalescence efficiency is developed for the population balance framework based on the film drainage model. The elaborate submodel considers the desorption energy required to detach a particle from the interface, representing an energy barrier against coalescence. With an additional implemented function in the population balance framework, the interface coverage rate by particles is calculated for each time step. The transient change of the coverage degree of the phase interface by particles is thereby considered in the submodel. Validation of the modified submodel was performed with experimental data of agitated water-in-oil (w/o) dispersions, stabilized by well-defined spherical silica nanoparticles. The nanospheres with a size of 28 nm are positively charged and were hydrophobized by silanization with dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammoniumchloride. This modeling approach is a first step toward predicting time-resolved dynamic drop size distributions of nanoparticle-stabilized liquid/liquid systems.

Style APA, Harvard, Vancouver, ISO itp.

18

Metin, Cigdem O., Larry W. Lake, Caetano R. Miranda i Quoc P. Nguyen. "Stability of aqueous silica nanoparticle dispersions". Journal of Nanoparticle Research 13, nr 2 (17.09.2010): 839–50. http://dx.doi.org/10.1007/s11051-010-0085-1.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

19

Sahu, Manoranjan, Komkrit Suttiponparnit, Sirikalaya Suvachittanont, Tawatchai Charinpanitkul i Pratim Biswas. "Characterization of doped TiO2 nanoparticle dispersions". Chemical Engineering Science 66, nr 15 (sierpień 2011): 3482–90. http://dx.doi.org/10.1016/j.ces.2011.04.003.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

20

Horie, Masanori, Keiko Nishio, Haruhisa Kato, Shigehisa Endoh, Katsuhide Fujita, Ayako Nakamura, Arisa Miyauchi i in. "The Expression of Inflammatory Cytokine and Heme Oxygenase-1 Genes in THP-1 Cells Exposed to Metal Oxide Nanoparticles". Journal of Nano Research 30 (marzec 2015): 116–27. http://dx.doi.org/10.4028/www.scientific.net/jnanor.30.116.

Pełny tekst źródła

Streszczenie:

The effect of manufactured nanoparticles on the expression of proinflammatory cytokine genes was examined. THP-1 cells differentiated into macrophage cells were exposed to TiO2 and NiO medium dispersions. After 2, 6, 12, or 24 hours exposure, the expression of IL-1β, IL-6, IL-8, TNF-α and HO-1 genes was determined by real-time PCR. TiO2 nanoparticles did not affect cytokine production. In addition, TiO2 nanoparticles did not dissolve in the dispersion. On the other hand, NiO nanoparticles enhanced the expression of all the genes tested. NiO dispersions were composed of 58.3 μg/mL of NiO nanoparticles and 45.8 μg/mL of Ni2+. The release of metal ions from the nanoparticles is associated with their cytotoxicity. Therefore, the effect of an NiCl2 solution containing 45.8 μg/mL of Ni2+ on the expression of cytokine genes was also examined. The effects of NiCl2 were similar to those of the NiO nanoparticles. Furthermore, the effect of ZnO, SiO2-coated ZnO, Sb2O3, and Cr2O3 nanoparticles on the expression of IL-1β, IL-8 and TNF-α genes was examined. Soluble nanoparticles, such as ZnO, SiO2-coated ZnO, and Cr2O3 enhanced the gene expression of cytokines. Sb2O3 nanoparticles showed poor solubility and did not affect the expression of cytokine genes. In conclusion, these results suggest that nanoparticle solubility plays an important role in regulating the expression of proinflammatory cytokines.

Style APA, Harvard, Vancouver, ISO itp.

21

Nechaeva, Olga V., Tatiana A. Shulgina, Ksenia V. Zubova, Elena V. Glinskaya, Natalia V. Bespalova, Nikolay I. Darin, Elena I. Tichomirova i Anna G. Afinogenova. "Antimicrobial activity of aqueous dispersions of silver nanoparticles against pathogens of purulent-inflammatory diseases". Russian Journal of Infection and Immunity 12, nr 4 (9.09.2022): 755–64. http://dx.doi.org/10.15789/2220-7619-aao-1937.

Pełny tekst źródła

Streszczenie:

Currently, metal nanostructures are widely used in medical, microbiological, and veterinary practice. Silver nanoparticles are especially promising as antimicrobial agents, becauseno published data regarding antimicrobial resistance are available. Whiledeveloping preparations based on metal nanoparticles, an important remainingissue is the choice of a stabilizer, introduction of which during the synthesis ensures the preservation of structures at the nanoscale range, and, consequently, relevant main characteristics, including biocidal properties. The object of the study was to investigate silver nanoparticle aqueous dispersions stabilized by natural and synthetic polymeric compounds. Routine strains of Gram-positive and Gram-negative bacteria were used as experimental models: S. aureus 209 P, Escherichia coli ATCC 25922, Proteus mirabilis ATCC 3177 (O-form), Klebsiella pneumoniae ATCC 31488, obtained from the Scientific Centre for Expert Evaluation of Medicinal Products. The antimicrobial activity of diverse variants of silver nanoparticle aqueous dispersions was assessed by serial dilution platingon dense nutrient medium. In this work, we examined no effect of silver nanoparticles without stabilizers, because their absence led to rapid agglomeration of nanostructures and loss of nanoscale characteristics. The highest sensitivity of Gram-positive and Gram-negative bacteria was foundto the action of ansilver nanoparticle aqueous dispersions stabilized by polyazolidinammoniumand modified with iodine hydrate ions. Drug working concentrations ranging from 0.5 to 3% had a bactericidal effect against pathogens of purulent-inflammatory diseases, and the minimum working concentration of 0.125% led to decreased colony-forming units by 2057% for diverse bacterial strains. Silver nanoparticles stabilized with sodium dodecyl sulfate showed high efficiency against the studied test strainsprobably due to the high toxicity of the stabilizer used as was previously established during a comprehensive safety assessment using biotest objects and cell cultures. In this regard, its use as a component of antimicrobial preparations is not preferred. The results of the studies showed that among the variants of silver nanoparticle aqueous dispersions, preparations stabilized with polyvinyl alcohol and polyazolidinammonium modified with iodine hydrate ions are the most promising for use in biomedical practice, because they demonstrate a high level of antibacterial activity against both Gram-positive and Gram-negative bacteria as causative agents of purulent-inflammatory diseases and a low toxicity level. This allows us to recommend them as safe and effective antimicrobial components indisinfectants, as well as antiseptic preparations for prevention and treatment of skin and soft tissue infectious diseases.

Style APA, Harvard, Vancouver, ISO itp.

22

Lee, Eun Hee, Min Ku Lee i Chang Kyu Rhee. "Preparation and Characterization of Stable Dispersions of Ni Nanoparticles". Materials Science Forum 534-536 (styczeń 2007): 117–20. http://dx.doi.org/10.4028/www.scientific.net/msf.534-536.117.

Pełny tekst źródła

Streszczenie:

Colloid stability of the suspensions of Ni nanoparticles has been investigated with adding polymeric dispersant in various organic media. We characterized the dispersion stability of Ni nanoparticles by means of visual inspection, transmission profiles measured by Turbiscan, the particle size distribution, and the zeta potential. 0.01 wt% of Ni nanoparticles were found to be optimally dispersed in ethanol among various organic media employed in this study with adding the dispersant (0.6 wt%-2 wt%). As the concentration of the dispersant increased, the particle size decreased in size from 300 nm to 200 nm due to less coalescence. The zeta potential values of the Ni nanoparticles in suspensions with the dispersant were greater than -40mV. Such stable Ni nanoparticle suspensions are attributed to the electrosteric effect of the polymeric dispersant.

Style APA, Harvard, Vancouver, ISO itp.

23

Nastulyavichus, A. A., S. I. Kudryashov, A. M. Emelyanenko i L. B. Boinovich. "Laser Generation of Colloidal Nanoparticles in Liquids: Key Processes of Laser Dispersion and Main Characteristics of Nanoparticles". Colloid Journal 85, nr 2 (kwiecień 2023): 233–50. http://dx.doi.org/10.1134/s1061933x23600136.

Pełny tekst źródła

Streszczenie:

Abstract The processes of laser dispersion of materials for high-performance generation of colloidal nanoparticles in liquids have been considered. Various laser and material parameters affecting this process have been studied. Efficiencies and ergonomics of the generation of colloidal nanoparticles with the help of laser systems having nano-, pico-, and femtosecond pulse durations have been compared using optical and mass criteria by the example of laser ablation of a chemically inert model material (gold) in distilled water without the use of chemical stabilizers. The main characteristics of gold and silver nanoparticles obtained by ablation in water using pulsed laser radiation of different durations have been comprehensively compared. The types of colloidal interactions between nanoparticles in aqueous media have been discussed, and the contributions of structural and ion-electrostatic interactions to the long-term stability of gold and silver nanoparticle dispersions have been analyzed.

Style APA, Harvard, Vancouver, ISO itp.

24

Rozhkov, S. P., Natalia N. Rozhkova i Maxim М. Sychov. "Shungite Carbon Nanoparticles as Modifiers of Zns:Cu Phosphor, Based on Analysis of the EPR Spectral Lines of Mn⁺²". Materials Science Forum 1031 (maj 2021): 201–8. http://dx.doi.org/10.4028/www.scientific.net/msf.1031.201.

Pełny tekst źródła

Streszczenie:

Water dispersions of shungite carbon (ShC) nanoparticles were used for modifying the particle surface of ZnS:Cu, commercial electrophosphor. The EPR spectrum of ZnS:Cu powder has parameters consistent with the paramagnetic centers of Mn+2. Modifying the phodphor surface with ShC nanoparticles results in a non-monotonic change in line width, amplitude and integral intensity caused by nanoparticle concentration, which correlates with variations in the brightness of electroluminescence. Variations in the parameters of spectral lines with nanoparticle concentration and UHF saturation power are interpreted in terms of modification and creation of additional dislocations in the subsurface layer of phosphor with new physico-chemical properties.

Style APA, Harvard, Vancouver, ISO itp.

25

Korskanov, V. V., O. M. Fesenko, T. V. Tsebrienko, O. P. Budnik i V. B. Dolgoshey. "The influence of gold nanoparticles on the thermal conductivity of water solutions of graphen". Кераміка: наука і життя, nr 4(45) (27.12.2019): 14–20. http://dx.doi.org/10.26909/csl.4.2019.2.

Pełny tekst źródła

Streszczenie:

The objects of study were water dispersions of raw graphene (hereinafter referred to as graphene-n), higher degree of purification of graphene samples (hereinafter graphene), and nanoparticles of graphene-Au nanoparticles based on them. The thermal conductivity of water graphene dispersions and water dispersions of gold graphene nanoparticles nanostructures at different temperatures and component ratios was investigated. The values of effective thermal conductivity of dry nanofillers are calculated. The temperature dependences of the thermal conductivity of the nanofillers were obtained. It is found that the in-thermal conductivity of water dispersions of purified graphene is higher than the thermal conductivity of raw graphene as a result of better packing of nanoparticles in pure graphene nanofillers compared to raw. The effect of enhancement of thermal conductivity of gold nanoparticles, which is accompanied by higher absolute values of thermal conductivity of nanoparticles of graphene-nanoparticles of gold than the corresponding graphene, was revealed. At the same time, there is a significant difference in thermal conductivity between nanoparticles of graphene nanoparticles of gold. It is established that higher values of thermal conductivity of graphene-nanoparticles nanostructures of gold are the result of the reinforcing action of a gold nanoparticle substrate, which is formed as a result of joint sedimentation with graphene during the formation of nano-flakes from water solution during evaporation of water.

Style APA, Harvard, Vancouver, ISO itp.

26

Laka, Marianna, Marite Skute, Sarmite Janceva, Velta Fridrihsone, Inese Sable, Linda Vecbiskena, Uldis Grinfelds, Laura Andze i Juris Zoldners. "Nanoparticle Gels Obtained from Hardwood and Softwood Bark for Reinforcing of Paper". Solid State Phenomena 267 (październik 2017): 12–16. http://dx.doi.org/10.4028/www.scientific.net/ssp.267.12.

Pełny tekst źródła

Streszczenie:

For reinforcing of paper, nanoparticle gels from black alder, birch and pine bark were obtained. Non-extracted bark and that extracted in biorefinery were used. For producing nanoparticles, the materials were destructed using the thermocatalytic destruction method and then dispersed in water medium in a ball mill. At a sufficient concentration, gel-like dispersions were obtained, which contained nanoparticles with the size ~300 nm. The effect of nanoparticle gels on the properties of paper sheets was investigated by introducing the dissolved gels in paper furnish and by covering both sides of paper sheets with nanoparticle gel coatings. It has been established that the nanoparticle fillers increase the tensile and burst strength. The nanoparticle fillers from extracted bark increase the mechanical indices to a higher extent. The coatings from nanoparticle gels considerably improve the Gurley air resistance of paper and increase the mechanical indices of paper sheets, especially burst strength. The effect of nanoparticle gel coatings is dependent on the coating thickness and gel concentration. The coatings decrease the tensile strength in a wet state.

Style APA, Harvard, Vancouver, ISO itp.

27

Shalaev, Pavel V., Polina A. Monakhova i Sergey A. Tereshchenko. "Study of colloidal gold nanorods in liquid dispersions using light scattering methods". Modern Electronic Materials 7, nr 2 (30.06.2021): 53–61. http://dx.doi.org/10.3897/j.moem.7.2.75519.

Pełny tekst źródła

Streszczenie:

Five samples of liquid dispersions of colloidal gold nanorods having various aspect ratios have been studied using light scattering methods. Transmission electron microscopy has been employed as a reference method. Advantages and drawbacks of dynamic light scattering and nanoparticle tracking analysis methods for study of nanoparticle geometrical parameters and concentration, sample monodispersity degree and detection of large particle aggregations and quasispherical impurities have been demonstrated. We show that depolarized dynamic light scattering method can be used for analysis of geometrical parameters of colloidal gold nanorods in liquid dispersions. The measurement results depend largely on the presence of large impurity particles or particle aggregations in samples. In turn the presence of large particles in dispersions can be detected using dynamic light scattering methods or nanoparticle tracking analysis. Dynamic light scattering method is more sensitive to the presence of even small quantities of large impurities or aggregations in samples. The monodispersity degree of nanorod liquid dispersions can also be assessed using dynamic light scattering and nanoparticle tracking analysis methods, and the measurement results can be considered more statistically significant in comparison with electron microscopy because a larger number of particles are analyzed. An increase in the concentration of spherical particles in compound dispersions of colloidal gold nanospheres and nanorods leads to a decrease in the contribution of the rotational mode to the overall scattering intensity. Data on the concentration of quasispherical impurities in samples of colloidal gold nanorod liquid dispersions have been reported on the basis of scattered light depolarization degree measurements.

Style APA, Harvard, Vancouver, ISO itp.

28

Wen, Haotian, José María Luna-Romera, José C. Riquelme, Christian Dwyer i Shery L. Y. Chang. "Statistically Representative Metrology of Nanoparticles via Unsupervised Machine Learning of TEM Images". Nanomaterials 11, nr 10 (14.10.2021): 2706. http://dx.doi.org/10.3390/nano11102706.

Pełny tekst źródła

Streszczenie:

The morphology of nanoparticles governs their properties for a range of important applications. Thus, the ability to statistically correlate this key particle performance parameter is paramount in achieving accurate control of nanoparticle properties. Among several effective techniques for morphological characterization of nanoparticles, transmission electron microscopy (TEM) can provide a direct, accurate characterization of the details of nanoparticle structures and morphology at atomic resolution. However, manually analyzing a large number of TEM images is laborious. In this work, we demonstrate an efficient, robust and highly automated unsupervised machine learning method for the metrology of nanoparticle systems based on TEM images. Our method not only can achieve statistically significant analysis, but it is also robust against variable image quality, imaging modalities, and particle dispersions. The ability to efficiently gain statistically significant particle metrology is critical in advancing precise particle synthesis and accurate property control.

Style APA, Harvard, Vancouver, ISO itp.

29

Hofer, Corinne J., Martin Zeltner, Robert N. Grass i Wendelin J. Stark. "Stable Ferromagnetic Nanoparticle Dispersions in Aqueous Solutions". CHIMIA International Journal for Chemistry 69, nr 6 (24.06.2015): 369. http://dx.doi.org/10.2533/chimia.2015.369.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

30

Kim, Seongbeom, Bright Walker, Song Yi Park, Hyosung Choi, Seo-Jin Ko, Jaeki Jeong, Myoung Hee Yun, Jeong Chul Lee, Dong Suk Kim i Jin Young Kim. "Size tailoring of aqueous germanium nanoparticle dispersions". Nanoscale 6, nr 17 (25.06.2014): 10156. http://dx.doi.org/10.1039/c4nr01596g.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

31

Loria, Herbert, Pedro Pereira-Almao i Carlos E. Scott. "Determination of Agglomeration Kinetics in Nanoparticle Dispersions". Industrial & Engineering Chemistry Research 50, nr 14 (20.07.2011): 8529–35. http://dx.doi.org/10.1021/ie200135r.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

32

Harris, L. A., J. D. Goff, A. Y. Carmichael, J. S. Riffle, J. J. Harburn, T. G. St. Pierre i M. Saunders. "Magnetite Nanoparticle Dispersions Stabilized with Triblock Copolymers". Chemistry of Materials 15, nr 6 (marzec 2003): 1367–77. http://dx.doi.org/10.1021/cm020994n.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

33

Zhang, Hui, Hui-Jiuan Chen, Xiaoze Du i Dongsheng Wen. "Photothermal conversion characteristics of gold nanoparticle dispersions". Solar Energy 100 (luty 2014): 141–47. http://dx.doi.org/10.1016/j.solener.2013.12.004.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

34

Nitschke, Christian, Seán M. O’Flaherty, Michael Kröll, James J. Doyle i Werner J. Blau. "Optical properties of zinc phthalocyanine nanoparticle dispersions". Chemical Physics Letters 383, nr 5-6 (styczeń 2004): 555–60. http://dx.doi.org/10.1016/j.cplett.2003.11.071.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

35

Cheng, Christopher J., i Owen G. Jones. "Stabilizing zein nanoparticle dispersions with ι-carrageenan". Food Hydrocolloids 69 (sierpień 2017): 28–35. http://dx.doi.org/10.1016/j.foodhyd.2017.01.022.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

36

Frolov, Georgy A., Yakov N. Karasenkov, Alexander A. Gusev, Olga V. Zakharova, Anna Yu Godymchuk, Denis V. Kuznetsov i Valerii K. Leont'ev. "Antimicrobial Activity of Differently Concentrated Nanoparticle Dispersions". Nano Hybrids and Composites 13 (styczeń 2017): 239–47. http://dx.doi.org/10.4028/www.scientific.net/nhc.13.239.

Pełny tekst źródła

Streszczenie:

Preparation of nontoxic antimicrobial solutions is a priority in the development of new antibiotics. The in vitro effect of the chemical composition of the dispersed phase and dissolved solids in the dispersion medium on the antimicrobial properties of aqueous colloidal solutions of nanoparticles of a number of metals and metal oxides against microorganisms of different species - bacterial dental plaque, Bacillus cereus, and spores of vaccine strain Bacillus anthracis STI - 1 were studied in this work.

Style APA, Harvard, Vancouver, ISO itp.

37

Hu, Z., i X. Xia. "Hydrogel Nanoparticle Dispersions with Inverse Thermoreversible Gelation". Advanced Materials 16, nr 4 (17.02.2004): 305–9. http://dx.doi.org/10.1002/adma.200305560.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

38

Huber, Johannes, i Stefan Mecking. "Processing of Polyacetylene from Aqueous Nanoparticle Dispersions". Angewandte Chemie 118, nr 38 (25.09.2006): 6462–65. http://dx.doi.org/10.1002/ange.200601694.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

39

Huber, Johannes, i Stefan Mecking. "Processing of Polyacetylene from Aqueous Nanoparticle Dispersions". Angewandte Chemie International Edition 45, nr 38 (25.09.2006): 6314–17. http://dx.doi.org/10.1002/anie.200601694.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

40

Hirama, Hirotada, Ryutaro Otahara, Shinya Kano, Masanori Hayase i Harutaka Mekaru. "Characterization of Nanoparticle Adsorption on Polydimethylsiloxane-Based Microchannels". Sensors 21, nr 6 (11.03.2021): 1978. http://dx.doi.org/10.3390/s21061978.

Pełny tekst źródła

Streszczenie:

Nanoparticles (NPs) are used in various medicinal applications. Exosomes, bio-derived NPs, are promising biomarkers obtained through separation and concentration from body fluids. Polydimethylsiloxane (PDMS)-based microchannels are well-suited for precise handling of NPs, offering benefits such as high gas permeability and low cytotoxicity. However, the large specific surface area of NPs may result in nonspecific adsorption on the device substrate and thus cause sample loss. Therefore, an understanding of NP adsorption on microchannels is important for the operation of microfluidic devices used for NP handling. Herein, we characterized NP adsorption on PDMS-based substrates and microchannels by atomic force microscopy to correlate NP adsorptivity with the electrostatic interactions associated with NP and dispersion medium properties. When polystyrene NP dispersions were introduced into PDMS-based microchannels at a constant flow rate, the number of adsorbed NPs decreased with decreasing NP and microchannel zeta potentials (i.e., with increasing pH), which suggested that the electrostatic interaction between the microchannel and NPs enhanced their repulsion. When exosome dispersions were introduced into PDMS-based microchannels with different wettabilities at constant flow rates, exosome adsorption was dominated by electrostatic interactions. The findings obtained should facilitate the preconcentration, separation, and sensing of NPs by PDMS-based microfluidic devices.

Style APA, Harvard, Vancouver, ISO itp.

41

Gupta, Meenal, Ipsita Satpathy, Arun Roy i R. Pratibha. "Nanoparticle induced director distortion and disorder in liquid crystal-nanoparticle dispersions". Journal of Colloid and Interface Science 352, nr 2 (grudzień 2010): 292–98. http://dx.doi.org/10.1016/j.jcis.2010.08.027.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

42

Ntente, C., A. Strekla, Z. Iatridi, M. Theodoropoulou, G. Bokias i C. D. Tsakiroglou. "Polymer-functionalized nanoparticles as agents for the in situ remediation of oil-contaminated soils". IOP Conference Series: Earth and Environmental Science 1123, nr 1 (1.12.2022): 012064. http://dx.doi.org/10.1088/1755-1315/1123/1/012064.

Pełny tekst źródła

Streszczenie:

Abstract In-situ flushing of chemicals, such as nanoparticle (NP) suspensions, and NP-based Pickering emulsions, is a well-promising method for the remediation of soils and aquifers contaminated with non-aqueous phase liquids (NAPLs) and the enhanced oil recovery from reservoir rocks. Linear and comb-type copolymers were synthesized by combining (i) hydrophilic, anionic monomers like 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPSA) and acrylic acid (AA) with (ii) hydrophobic monomers like dodecyl methacrylate (DMA). Moreover, polymer-coated nanoparticles (PNPs) was prepared by post-grafting and surface initiated free radical polymerization (FRP) on commercial silica nanoparticles. Dilute dispersions of polymers and PNPs were mixed with salts (NaCl, CaCl2), their dynamic surface and oil/water interfacial tensions were measured by the pendant drop method, and the wettability of all fluid systems to glass surface was quantified by measuring the contact angle. Oil-in-water Pickering emulsions were prepared by dispersing n-dodecane in polymers and n-decane in PNP-colloid with ultrasound probe, and their stability was evaluated by tracking the phase separation and changes of rheological properties, as functions of time. Furthermore, the most stable polymers and PNP-based dispersions and emulsions were chosen and tested as chemicals for the removal of residual oil from a transparent glass-etched pore network.

Style APA, Harvard, Vancouver, ISO itp.

43

Gavrielatos, I., R. Dabirian, R. Mohan i O. Shoham. "Comparison of Nanoparticle and Surfactant Oil/Water-Emulsion Separation Kinetics". SPE Journal 24, nr 05 (14.05.2019): 2182–94. http://dx.doi.org/10.2118/190114-pa.

Pełny tekst źródła

Streszczenie:

Summary Experimental observations, during oil–production operations, regarding the formation of oil/water emulsions stabilized by nanoparticles and surfactants, are presented. Similarities and differences between the two types of emulsions are discussed on the basis of acquired separation profiles, as well as respective fluid interfacial properties. A state–of–the–art portable dispersion–characterization rig (PDCR) was used to run the experiments, and a surveillance camera was deployed to monitor the emulsion separation kinetics. Commercial–grade mineral oil and distilled water were used as the test fluids. Silica nanoparticles of different wettabilities, as well as surfactants with different hydrophilic-lipophilic balance (HLB) values, were deployed to investigate commonalities/differences between the surfactant– and nanoparticle–stabilized emulsions under ambient–temperature and –pressure conditions. Separation profiles were analyzed, and similar behaviors between the corresponding surfactant and nanoparticle emulsions were observed for the 25%–water–cut case. For higher water cuts, however, the surfactant–stabilized emulsions were tighter than their nanoparticle counterparts, displaying much lower separation rates. In the most severe cases, the surfactants totally inhibited the oil–creaming process and oil remained trapped in the emulsion for several hours. Multiple emulsions (O/W/O) were observed in certain cases [for hydrophilic nanoparticles and lipophilic surfactants (Span® 80)]. On the basis of the aforementioned experimental observations, the presence of surfactants caused more–severe problems for the oil/water–separation process than did the presence of an equal concentration of nanoparticles. Pendant–drop measurements indicated that the surfactants significantly lowered the interfacial tension (IFT) between the oil and water, whereas the nanoparticles did not. Finally, a literature model was used to predict separation profiles for the oil/water dispersions and evaluated by comparing the predictions with the acquired experimental data. Current research sets the benchmark for more–thorough investigations aimed at providing guidelines for a more efficient operation of separators that handle surfactant– or nanoparticle–stabilized emulsions and a better understanding of the related phenomena.

Style APA, Harvard, Vancouver, ISO itp.

44

Yang, Lulu, Zhibin Yan, Lu Yang, Jianxin Yang, Mingliang Jin, Xiaobo Xing, Guofu Zhou i Lingling Shui. "Photothermal conversion of SiO2@Au nanoparticles mediated by surface morphology of gold cluster layer". RSC Advances 10, nr 55 (2020): 33119–28. http://dx.doi.org/10.1039/d0ra06278b.

Pełny tekst źródła

Streszczenie:

We manipulate the surface morphology of gold clusters on SiO₂@Au nanoparticle and found that macroscopic photothermal conversions of different nanoparticle dispersions are significantly affected by nanoscale differences of gold cluster morphologies.

Style APA, Harvard, Vancouver, ISO itp.

45

Lievonen, Miikka, Juan José Valle-Delgado, Maija-Liisa Mattinen, Eva-Lena Hult, Kalle Lintinen, Mauri A. Kostiainen, Arja Paananen, Géza R. Szilvay, Harri Setälä i Monika Österberg. "A simple process for lignin nanoparticle preparation". Green Chemistry 18, nr 5 (2016): 1416–22. http://dx.doi.org/10.1039/c5gc01436k.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

46

Appel, Christian, Björn Kuttich, Tobias Kraus i Bernd Stühn. "In situ investigation of temperature induced agglomeration in non-polar magnetic nanoparticle dispersions by small angle X-ray scattering". Nanoscale 13, nr 14 (2021): 6916–20. http://dx.doi.org/10.1039/d0nr08434d.

Pełny tekst źródła

Streszczenie:

Non-polar magnetic nanoparticles agglomerate upon cooling. The agglomeration is driven by either directed magnetic dipole interactions or isotropic van der Waals interactions depending on the size of the nanoparticle.

Style APA, Harvard, Vancouver, ISO itp.

47

Kendall, K., R. Amal, X. Jiang i A. Yu. "Effect of Adhesion on Aggregation in Nanoparticle Dispersions". Journal of Adhesion 83, nr 6 (12.07.2007): 573–85. http://dx.doi.org/10.1080/00218460701453569.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

48

Gebauer, J. S., V. Mackert, S. Ognjanović i M. Winterer. "Tailoring metal oxide nanoparticle dispersions for inkjet printing". Journal of Colloid and Interface Science 526 (wrzesień 2018): 400–409. http://dx.doi.org/10.1016/j.jcis.2018.05.006.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

49

Yuan, Xiaofeng, Matthias Schnell, Sandra Muth i Wolfgang Schärtl. "Cluster Formation and Rheology of Photoreactive Nanoparticle Dispersions". Langmuir 24, nr 10 (maj 2008): 5299–305. http://dx.doi.org/10.1021/la800043j.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

50

Moulton, S. E., P. C. Innis, L. A. P. Kane-Maguire, O. Ngamna i G. G. Wallace. "Polymerisation and characterisation of conducting polyaniline nanoparticle dispersions". Current Applied Physics 4, nr 2-4 (kwiecień 2004): 402–6. http://dx.doi.org/10.1016/j.cap.2003.11.059.

Pełny tekst źródła

Style APA, Harvard, Vancouver, ISO itp.

Artykuły w czasopismach na temat „Nanoparticle dispersions”

Utwórz poprawne odniesienie w stylach APA, MLA, Chicago, Harvard i wielu innych