Relevant bibliographies by topics / Nanoparticle size

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  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'Nanoparticle size'

Author: Grafiati
Published: 4 June 2021
Last updated: 15 February 2022

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Journal articles on the topic "Nanoparticle size"

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Li, Meng, Liqiang Lin, Ruyan Guo, Amar Bhalla, and Xiaowei Zeng. "Numerical investigation of size effects on mechanical behaviors of Fe nanoparticles through an atomistic field theory." Journal of Micromechanics and Molecular Physics 02, no. 03 (September 2017): 1750010. http://dx.doi.org/10.1142/s2424913017500102.

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At nanoscale, the mechanical response of nanoparticles is largely affected by the particle size. To assess the effects of nanoparticle size (e.g., nanoparticle’s volume, cross-sectional area and length) on mechanical behaviors of bcc Fe nanoparticles under compressive loading, an atomistic field theory was introduced in current study. In the theory, atomistic definitions and continuous local density functions of fundamental physical quantities were derived. Through the atomistic potential-based method, the mechanical responses of bcc Fe nanoparticles were analyzed in different sizes. The simulation results reveal that the ultimate stress decreases as Fe nanoparticle’s volume, cross-sectional area or length increases under compressive loading. Nonetheless, the Young’s modulus increases as nanoparticle size increases. In addition, for a fixed finite volume nanoparticle, this study indicates that the ultimate stress will increase as strain rate increases, but Young’s modulus will decrease with increasing strain rate. A loading–unloading study illustrates the energy dissipation due to irreversible structure changes in Fe nanoparticles.
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Bao, Lingling, Chaoyang Zhong, Pengfei Jie, and Yan Hou. "The effect of nanoparticle size and nanoparticle aggregation on the flow characteristics of nanofluids by molecular dynamics simulation." Advances in Mechanical Engineering 11, no. 11 (November 2019): 168781401988948. http://dx.doi.org/10.1177/1687814019889486.

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Molecular dynamics simulation is used to investigate the flow characteristics of Cu–Ar nanofluids considering the influence of nanoparticle size and nanoparticle aggregation. Nanofluids viscosity is calculated by equilibrium molecular dynamics based on Green–Kubo equation. Results demonstrate that the viscosity of nanofluids decreases with the increase of nanoparticle size. In addition, nanoparticle aggregation results in the increase of the nanofluids viscosity. Compared with nanoparticle size, nanoparticle aggregation has a larger impact on viscosity. Nanofluids flowing in parallel-plate nanochannels are simulated. The velocity profiles are studied through three nanoparticle sizes (11.55, 14.55, and 18.33 Å) and four nanoparticle aggregate configurations. Results show that the velocity profile of 14.55 Å nanoparticle size is larger than that of other two nanoparticle sizes. As for four nanoparticles, the nanoparticles clustering as a line leads to the maximum velocity profile, while the nanoparticles clustering as a cube causes the minimum velocity profile. Compared with viscosity, nanoparticle aggregation has a greater effect on the velocity profile. When the nanoparticles are evenly distributed, the influence of viscosity on velocity profiles is dominant. Otherwise, the aggregation, aggregate configuration, and distribution of nanoparticles have a dominant impact on the flow characteristics of nanofluids.
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Neouze Gauthey, Marie-Alexandra, Marco Litschauer, Michael Puchberger, Martin Kronstein, and Herwig Peterlik. "Tuning the Pore Size in Ionic Nanoparticle Networks." Journal of Nanoparticles 2013 (March 11, 2013): 1–9. http://dx.doi.org/10.1155/2013/682945.

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Highly promising hybrid materials consisting of silica, titania, or zirconia nanoparticles linked with ionic liquid-like imidazolium units have been developed. The nanoparticle networks are prepared by click-chemistry-like process through a nucleophilic substitution reaction. The type of metal oxide nanoparticles appears to play a key role regarding the pore size of the hybrid material.
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Lavagna, Enrico, Jonathan Barnoud, Giulia Rossi, and Luca Monticelli. "Size-dependent aggregation of hydrophobic nanoparticles in lipid membranes." Nanoscale 12, no. 17 (2020): 9452–61. http://dx.doi.org/10.1039/d0nr00868k.

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Petithory, Tatiana, Laurent Pieuchot, Ludovic Josien, Arnaud Ponche, Karine Anselme, and Laurent Vonna. "Size-Dependent Internalization Efficiency of Macrophages from Adsorbed Nanoparticle-Based Monolayers." Nanomaterials 11, no. 8 (July 30, 2021): 1963. http://dx.doi.org/10.3390/nano11081963.

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Functional coatings based on the assembly of submicrometric or nanoparticles are found in many applications in the biomedical field. However, these nanoparticle-based coatings are particularly fragile since they could be exposed to cells that are able to internalize nanoparticles. Here, we studied the efficiency of RAW 264.7 murine macrophages to internalize physisorbed silica nanoparticles as a function of time and particle size. This cell internalization efficiency was evaluated from the damages induced by the cells in the nanoparticle-based monolayer on the basis of scanning electron microscopy and confocal laser scanning microscopy observations. The internalization efficiency in terms of the percentage of nanoparticles cleared from the substrate is characterized by two size-dependent regimes. Additionally, we highlighted that a delay before internalization occurs, which increases with decreasing adsorbed nanoparticle size. This internalization is characterized by a minimal threshold that corresponds to 35 nm nanoparticles that are not internalized during the 12-h incubation considered in this work.
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Peretz, Vital, Menachem Motiei, Chaim N. Sukenik, and Rachela Popovtzer. "The Effect of Nanoparticle Size on Cellular Binding Probability." Journal of Atomic, Molecular, and Optical Physics 2012 (June 7, 2012): 1–7. http://dx.doi.org/10.1155/2012/404536.

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Nanoparticle-based contrast agents are expected to play a major role in the future of molecular imaging due to their many advantages over the conventional contrast agents. These advantages include prolonged blood circulation time, controlled biological clearance pathways, and specific molecular targeting capabilities. Recent studies have provided strong evidence that molecularly targeted nanoparticles can home selectively onto tumors and thereby increase the local accumulation of nanoparticles in tumor sites. However, there are almost no reports regarding the number of nanoparticles that bind per cell, which is a key factor that determines the diagnostic efficiency and sensitivity of the overall molecular imaging techniques. Hence, in this research we have quantitatively investigated the effect of the size of the nanoparticle on its binding probability and on the total amount of material that can selectively target tumors, at a single cell level. We found that 90 nm GNPs is the optimal size for cell targeting in terms of maximal Au mass and surface area per single cancer cell. This finding should accelerate the development of general design principles for the optimal nanoparticle to be used as a targeted imaging contrast agent.
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Wang, Shenqing, Xiliang Yan, Gaoxing Su, and Bing Yan. "Cytotoxicity Induction by the Oxidative Reactivity of Nanoparticles Revealed by a Combinatorial GNP Library with Diverse Redox Properties." Molecules 26, no. 12 (June 14, 2021): 3630. http://dx.doi.org/10.3390/molecules26123630.

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It is crucial to establish relationship between nanoparticle structures (or properties) and nanotoxicity. Previous investigations have shown that a nanoparticle’s size, shape, surface and core materials all impact its toxicity. However, the relationship between the redox property of nanoparticles and their toxicity has not been established when all other nanoparticle properties are identical. Here, by synthesizing an 80-membered combinatorial gold nanoparticle (GNP) library with diverse redox properties, we systematically explored this causal relationship. The compelling results revealed that the oxidative reactivity of GNPs, rather than their other physicochemical properties, directly caused cytotoxicity via induction of cellular oxidative stress. Our results show that the redox diversity of nanoparticles is regulated by GNPs modified with redox reactive ligands.
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Muneesawang, Paisarn, and Chitnarong Sirisathitkul. "Size Measurement of Nanoparticle Assembly Using Multilevel Segmented TEM Images." Journal of Nanomaterials 2015 (2015): 1–8. http://dx.doi.org/10.1155/2015/790508.

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Multilevel image segmentation is demonstrated as a rapid and accurate method of quantitative analysis for nanoparticle assembly in TEM images. The procedure incorporatingK-means clustering algorithm and watershed transform is tested on transmission electron microscope (TEM) images of FePt-based nanoparticles whose diameters are less than 5 nm. By solving the nanoparticle segmentation and separation problems, this unsupervised method is useful not only in the nonoverlapping case but also for agglomerated nanoparticles. Furthermore, the method exhibits scale invariance based on comparable results from images of different magnifications.
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Szałaj, Urszula, Anna Świderska-Środa, Agnieszka Chodara, Stanisław Gierlotka, and Witold Łojkowski. "Nanoparticle Size Effect on Water Vapour Adsorption by Hydroxyapatite." Nanomaterials 9, no. 7 (July 12, 2019): 1005. http://dx.doi.org/10.3390/nano9071005.

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Handling and properties of nanoparticles strongly depend on processes that take place on their surface. Specific surface area and adsorption capacity strongly increase as the nanoparticle size decreases. A crucial factor is adsorption of water from ambient atmosphere. Considering the ever-growing number of hydroxyapatite nanoparticles applications, we decided to investigate how the size of nanoparticles and the changes in relative air humidity affect adsorption of water on their surface. Hydroxyapatite nanoparticles of two sizes: 10 and 40 nm, were tested. It was found that the nanoparticle size has a strong effect on the kinetics and efficiency of water adsorption. For the same value of water activity, the quantity of water adsorbed on the surface of 10 nm nano-hydroxyapatite was five times greater than that adsorbed on the 40 nm. Based on the adsorption isotherm fitting method, it was found that a multilayer physical adsorption mechanism was active. The number of adsorbed water layers at constant humidity strongly depends on particles size and reaches even 23 layers for the 10 nm particles. The amount of water adsorbed on these particles was surprisingly high, comparable to the amount of water absorbed by the commonly used moisture-sorbent silica gel.
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Ningrum, Wulan Agustin, W. Wirasti, Yulian Wahyu Permadi, and Fida Faiqatul Himmah. "Uji Sediaan Lotion Nanopartikel Ekstrak Terong Belanda Sebagai Antioksidan." Jurnal Ilmiah Kesehatan 14, no. 1 (March 29, 2021): 99. http://dx.doi.org/10.48144/jiks.v14i1.539.

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Abstrak. Nanopartikel adalah suatu teknologi formulasi suatu partikel yang terdispersi pada ukuran nanometer atau skala per seribu mikron. Tujuan penelitian ini adalah membuat sediaan lotion dari nanopartikel ekstrak terong belanda sebagai antioksidan. Teknologi nanopartikel ekstrak terong belanda mempunyai efek yang sangat baik sebagai antioksidan, sehingga dimungkinkan dibuat sediaan sebagai bahan kosmetik Penelitian ini menguji nanopertikel ekstrak terong belanda sebagai antioksidan sediaan lotion. Metode ekstraksi yang digunakan dalam penelitian ini adalah maserasi menggunakan pelarut metanol. Pembuatan teknologi nanopartikel ekstrak terong belanda menggunakan metode nanopertikel berbasis biopolimer. Nanopartikel ekstrak terong belanda diformulasi menjadi sediaan lotion. Uji aktivitas antioksidan dilakukan dengan metode penangkap radikal bebas DPPH. Parameter aktivitas antioksidan yaitu IC50 (Inhibititon Concentration), sedangkan uji sediaan lotion terdiri dari pH, viskositas, stabilitas, organoleptis (warna, aroma, bentuk). Hasil dari penelitian menunjukkan Lotion ekstrak terong belanda yang dihasilkan memenuhi syarat evaluasi fisik sediaan. Nilai IC50 lotion nanopartikel ekstrak terong belanda adalah 62 µg/mL. Ukuran partikel dari ekstrak nanopartikel adalah 182,4 µm. Lotion nanopartikel ekstrak terong belanda mempunyai kestabilan yang baik. Perlu dilakukan pembuatan bentuk sediaan yang lain dengan tujuan sebagai kosmetika. Kata kunci : Ekstrak terong belanda, nanopartikel, lotion, IC50 Tamarillo Extract Nanoparticle Lotion Preparation Test As Antioxidant Abstract. Nanoparticles are a technology for the formulation of particles that are dispersed at the nanometer size or scale per thousand microns. The purpose of this study was to make lotion preparations from the nanoparticles of tamarillo extract as an antioxidant. The nanoparticle technology of tamarillo extract has a very good effect as an antioxidant, so it is possible to make a cosmetic ingredient. This study tested the nanoparticle extract of tamarillo as an antioxidant for lotion preparations. The extraction method used in this research is maceration using methanol as a solvent. The manufacture of tamarillo extract nanoparticle technology used a biopolymer-based nanoperticle method. The nanoparticles of tamarillo extract were formulated into lotions. The antioxidant activity test was carried out using the DPPH free radical scavenger method. The parameter of antioxidant activity is IC50 (Inhibititon Concentration), while the lotion preparation test consists of pH, viscosity, stability, organoleptic (color, aroma, shape). The results showed that the tamarillo extract lotion produced met the requirements for the physical evaluation of the preparation. The IC50 value of tamarillo extract nanoparticle lotion was 62 µg / mL. The particle size of the nanoparticle extract was 182.4 µm. Tamarillo extract nanoparticle lotion has good stability. It is necessary to make other dosage forms for the purpose of cosmetics. Keywords: Tamarillo extract, nanoparticle, lotion, IC50
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Dissertations / Theses on the topic "Nanoparticle size"

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Khadra, Ghassan. "Magnetic and structural properties of size-selected FeCo nanoparticle assemblies." Thesis, Lyon 1, 2015. http://www.theses.fr/2015LYO10145/document.

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Dans ce travail, nous nous sommes intéressés aux propriétés magnétiques intrinsèques (moments et anisotropie magnétiques) de nanoparticules bimétalliques fer-cobalt. Pour cela, des agrégats FeCo dans la gamme de taille 2-6 nm ont été préparés en utilisant la technique MS-LECBD (Mass Selected Low Energy Cluster Beam Deposition) et enrobés en matrice in − situ afin de les séparer, d'éviter leur coalescence pendant les recuits et de les protéger à leur sortie à l'air. Dans un premier temps, les propriétés structurales (dispersion de taille, morphologie, composition, structure cristallographique) ont été étudiées en vue de corréler directement les modifications des caractéristiques magnétiques des nanoparticules, à leur structure et à l'ordre chimique obtenu après traitement thermique haute température. D'autre part, pour mettre en évidence les effets d'alliages à cette échelle, des références d'agrégats purs de fer et de cobalt ont été fabriquées et étudiées en utilisant les mêmes techniques. Par microscopie électronique en transmission à haute résolution, diffraction anomale et absorption de rayons X (high resolution transmission electron microscopy (HRTEM), anomalous x-ray diffraction (AXD) and extended x-ray absorption fine structure (EXAFS), nous avons mis en évidence un changement structural depuis une phase A2 chimiquement désordonnée vers une phase B2 type CsCl chimiquement ordonnée. Cette transition a été validée par nos résultats obtenus par magnétomètrie SQUID et dichroïsme magnétique circulaire (x-ray magnetic circular dichroism (XMCD))
Over the past few decades, use of nanostructures has become widely popular in the different field of science. Nanoparticles, in particular, are situated between the molecular level and bulk matter size. This size range gave rise to a wide variety physical phenomena that are still not quite understood. Magnetic nanoparticles are at their hype due to their applications in medical field, as a catalyst in a wide number of chemical reactions, in addition to their use for information storage devices and spintronics. In this work, we are interested in studying the intrinsic magnetic properties (magnetic moments and anisotropy) of FeCo nanoparticles. Thus, in order to completely understand their properties, mass-selected FeCo nanoparticles were prepared using the MS-LECBD (Mass Selected Low Energy Cluster Beam Deposition) technique in the sizes range of 2-6 nm and in − situ embedded in a matrix in order to separate them, to avoid coalescence during the annealing and to protect during transfer in air. From a first time, the structural properties (size, morphology, composition, crystallographic structure) of these nanopar- ticles were investigated in order to directly correlate the modification of the magnetic properties to the structure and chemical ordering of the nanoparticles after high temperature treatment. In addition to the bimetallic FeCo nanoparticles, reference Fe and Co systems were also fabricated and studied using the same techniques. The structural properties were investigated using high resolution transmission electron microscopy (HRTEM), anomalous x-ray diffraction (AXD) and extended x-ray absorption fine structure (EXAFS) where a phase transition from a disordered A2 phase to a chemically ordered CsCl B2 phase was observed and further validated from the magnetic findings using SQUID magnetometry and x-ray magnetic circular dichroism (XMCD)
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Moffitt, Matthew. "Nanoparticle size control and coronal structure in block ionomer micelles." Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=35015.

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Quantum-confined semiconductors have been synthesized in ionomer microdomains, demonstrating thermodynamic control of nanoparticle sizes via a priori knowledge of ion aggregation numbers. In block ionomers, cadmium sulfide (CdS) nanoparticle sizes are found to scale with the ionic block length (N B) as NB3/5. CdS-polymer composites from block ionomers can be suspended in organic solvents as reverse micelles. Micelle stability is improved by reneutralization of acrylic acid blocks surrounding the nanoparticle. Reloading of microreactors and controlled continued growth of nanoparticles is demonstrated. Novel assemblies of CdS-containing reverse micelles are formed by secondary self-assembly in aqueous media. Scaling relations are also determined for microreactors containing different metal ions. For all metal ions investigated, the ionic core size scales as NB0.58+/-0.03, in agreement with starlike models; the proportionality constant is found to depend on the metal ion.
Coronal structure in block ionomers has been investigated by small-angle neutron scattering (SANS), using deuterated labels at various distances from the ionic core. Near the outside of the polymer brush, the scattered intensity scales with the scattering vector (q) as q --5/3, suggesting a semidilute environment for the label. Chain conformations are influenced by neighbouring coronae above the micelle overlap concentration. Closer to the ionic core, the chains become more crowded, and the semidilute assumption is not applicable. For labels directly connected to the core, intensity scaling suggests highly extended chains.
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Moffitt, Matthew. "Nanoparticle size control and coronal structure in block ionomer micelles." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape10/PQDD_0015/NQ44517.pdf.

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Blanco-Mantecon, Mireia. "Interactions, particle size and surface effects in magnetic nanoparticle systems." Thesis, Bangor University, 2000. https://research.bangor.ac.uk/portal/en/theses/interactions-particle-size-and-surface-effects-in-magnetic-nanoparticle-systems(2f7d3ef7-ef4c-43b0-b3ad-9e5c68f629e5).html.

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This work has involved the study of the magnetic behaviour of small magnetic nanoparticle systems. Due to the reduced size of magnetic nanoparticles they present distinctive properties, such as size and surface effects, that have been analysed in this work, as well as the effect of interactions in such systems. The samples chosen for the study were magnetite particles in the form of a ferrofluid and Co nanoclusters in a nonmagnetic matrix of Cu. Both systems present very narrow particle size distributions, which facilitates the interpretation of the data. The samples have been subjected to basic characterisation, which includes the determination of the distribution of magnetic particle sizes using the magnetisation curves at room temperatures, TEM microscopy and X-ray diffraction, in the case of the ferrofluid samples. For the nanoclusters, a time of flight spectrometer has been used to obtain the number of atoms per cluster. Many of the measurements have been performed at low temperatures, where thermal effects are minimised. For such measurements the samples have been frozen in a zero applied field, so that they have a random distribution of magnetic moments prior to the measurement. The energy barrier distributions have been calculated via the temperature decay of remanence (TDR). From this study, an effective anisotropy constant has been calculated. For the study of the interactions, surface and size effects, magnetisation, susceptibility (ZFC), remanence and delta-M curves, as well as the time dependence of magnetisation have been studied. The attempt frequency of the different particle size systems has been calculated using different techniques. The basic magnetic behaviour can be explained on the basis of the Neel blocking model. It has been found that the systems with the smaller particles have significant surface effects, which are enhanced at lower temperatures. Interactions, which are weak due to the low concentration of magnetic material in the samples (<10%), have been found to be overall demagnetising and the evolution of the magnetic properties with dilution has been explained. As is the case for the surface effects, interaction effects are stronger at low temperatures due the reduction of thermal effects. The experimental results have been compared with calculations from a Montecarlo model for fine particles, which includes the effects of concentration, anisotropy, particle size and temperature.
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Wilson, Austin T. "Measurement of Nanoparticle Size Distributions and Number of Nanoparticles Per Volume by Inductively Coupled Plasma Mass Spectrometry." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1471823411.

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Walji, Nimisha. "A systematic correlation of nanoparticle size with diffusivity through biological fluids." Thesis, Imperial College London, 2010. http://hdl.handle.net/10044/1/6080.

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Nanomedicine, the application of nanotechnology for medical purposes, has been widely identified as a potential solution for today‟s healthcare problems. Nanomedicine uses the "bottom-up‟ principles of nanoscale engineering to improve areas of medicine which have previously been considered undevelopable. One of the enduring challenges for medicine is the design of innovative devices able to overcome biological barriers, allowing drugs and therapeutics to effectively reach their correct location of action. Biological barriers are a defence mechanism of the body which are extremely well-evolved to protect the body from foreign and harmful particles. Therapeutic drugs and devices, which are not harmful, are often identified by the body as dangerous because their composition differs from native and accepted entities. The traversal of these biological barriers, such as mucus, remains a bottleneck in the progress of drug delivery and gene therapy. The mucus barrier physically limits the motion of particles due to its complicated mesh structure which obstructs the particles' traversal path. Mucus fibres can also adhere to the particles, entrapping them and restricting their motion. Particle traversal of mucus is carried out by passive diffusion. As diffusion has traditionally been defined by the Stokes-Einstein equation as inversely proportional to particle radius, it follows that reducing particle sizes into the nanoscale would result in increased diffusive ability. These predictions, however, do not consider the obstructive effects of the complicated mesh structure for the case of mucus. The exact effect of reducing particle size into the nanoscale for diffusion through mucus is therefore unknown. Multiple Particle Tracking was used to obtain real-time movies of the diffusion of nanoparticles, ranging from 12nm – 220nm in diameter, through mucus samples. The experimental data generated was used to systematically correlate the relationship between particle size and diffusivity through mucus. This study reveals that nanoparticles, smaller than the average pore size in the mucus mesh structure, can diffuse through lower viscosity pores which pose less resistance to diffusive motion, allowing nanoparticles to travel at up to four times the speed expected from the bulk viscosity of the mucus. This type of information can help researchers understand the importance of size for therapeutic nanoparticles, allowing researchers to decide whether attempts to decrease nanoparticle size at the expense of other functionality are worthwhile.
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Narayanan, Radha. "Shape-Dependent Nanocatalysis and the Effect of Catalysis on the Shape and Size of Colloidal Metal Nanoparticles." Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/6878.

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From catalytic studies in surface science, it has been shown that the catalytic activity is dependent on the type of metal facet used. Nanocrystals of different shapes have different facets. This raises the possibility that the use of metal nanoparticles of different shapes could catalyze different reactions with different efficiencies. The catalytic activity is found to correlate with the fraction of surface atoms located on the corners and edges of the tetrahedral, cubic, and spherical platinum nanoparticles. It is observed that for nanoparticles of comparable size, the tetrahedral nanoparticles have the highest fraction of surface atoms located on the corners and edges and also have the lowest activation energy, making them the most catalytically active. Nanoparticles have a high surface-to-volume ratio, which makes them attractive to use compared to bulk catalytic materials. However, their surface atoms are also very active due to their high surface energy. As a result, it is possible that the surface atoms are so active that their size and shape could change during the course of their catalytic function. It is found that dissolution of corner and edge atoms occurs for both the tetrahedral and cubic platinum nanoparticles during the full course of the mild electron transfer reaction and that there is a corresponding change in the activation energy in which both kinds of nanoparticles strive to behave like spherical nanoparticles. When spherical palladium nanoparticles are used as catalysts for the Suzuki reaction, it is found that the nanoparticles grow larger after the first cycle of the reaction due to the Ostwald ripening process since it is a relatively harsh reaction due to the need to reflux the reaction mixture for 12 hours at 100 oC. When the tetrahedral Pt nanoparticles are used to catalyze this reaction, the tetrahedral nanoparticles transform to spherical ones, which grow larger during the second cycle. In addition, studies on the effect of the individual reactant have also provided clues to the surface catalytic process that is taking place. In the case of the electron transfer reaction, the surface catalytic process involves the thiosulfate ions binding to the nanoparticle surface and reacting with the hexacyanoferrate (III) ions in solution. In the case of the Suzuki reaction, the surface catalytic mechanism of the Suzuki reaction involves the phenylboronic acid binding to the nanoparticle surface and reacting with iodobenzene via collisional processes.
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Liu, Chang. "Controlled Evaluation of Silver Nanoparticle Dissolution: Surface Coating, Size and Temperature Effects." Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/97509.

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The environmental fate and transport of engineered nanomaterials have been broadly investigated and evaluated in many published studies. Silver nanoparticles (AgNPs) represent one of the most widely manufactured nanomaterials. They are currently being incorporated into a wide range of consumer products due to their purported antimicrobial properties. However, either the AgNPs themselves or dissolved Ag+ ions has a significant potential for the environmental release. The safety issues for nanoparticles are continuously being tested because of their potential danger to the environment and human health. Studies have explored the toxicity of AgNPs to a variety of organisms and have shown such toxicity is primarily driven by Ag+ ion release. Dissolution of nanoparticles is an important process that alters their properties and is a critical step in determining their safety. Therefore, studying nanoparticles' dissolution can help in the current move towards safer design and application of nanoparticles. This research endeavor sought to acquire comprehensive kinetic data of AgNP dissolution to aid in the development of quantitative risk assessments of AgNP fate. To evaluate the dissolution process in the absence of nanoparticle aggregation, AgNP arrays were produced on glass substrates using nanosphere lithography (NSL). Changes in the size and shape of the prepared AgNP arrays were monitored during the dissolution process by atomic force microscopy (AFM). The dissolution of AgNP is affected by both internal and external factors. First, surface coating effects were investigated by using three different coating agents (BSA, PEG1000, and PEG5000). Capping agent effects nanoparticle transformation rate by blocking reactants from the nanoparticle surface. Coatings prevented dissolution to different extents due to the various way they were attached to the AgNP surface. Evidence for the existence of bonds between the coating agents and the AgNPs was obtained by surface enhanced Raman spectroscopy. Moreover, to study the size effects on AgNP dissolution, small, medium, and large sized AgNPs were used. The surrounding medium and temperature were the two variables that were included in the size effects study. Relationships were established between medium concentration and dissolution rate for three different sized AgNP samples. By using the Arrhenius equation to plot the reaction constant vs. reaction temperature, the activation energy of AgNPs of different sizes were obtained and compared.
Doctor of Philosophy
Nanomaterials, defined as materials with at least one characteristic dimension less than 100 nm, often have useful attributes that are distinct from the bulk material. The novel physical, chemical, and biological properties enable the promising applications in various manufacturing industry. Silver nanoparticles (AgNPs) represent one of the most widely manufactured nanomaterials and has been used as the antimicrobial agent in a wide range of consumer products. However, either the AgNPs themselves or dissolved Ag+ ions has a significant potential for the environmental release. The environmental fate and transport of AgNPs drawn considerable attentions because of the potential danger to environment and human health. Dissolution of nanoparticles is an important process that alters their properties and is a critical step in determining their safety. Ag+ ions migrate from the nanoparticle surface to the bulk solution when an AgNP dissolves. Studying nanoparticles' dissolution can help in the current move towards safer design and application of nanoparticles. This research aimed to acquire comprehensive kinetic data of AgNP dissolution to aid in the development of quantitative risk assessments of AgNP fate. AgNP arrays were produced on glass substrates using nanosphere lithography (NSL) and changes in the size and shape during the dissolution process were monitored by atomic force microscopy (AFM). First, surface coating effects were investigated by using three different coating agents. Coatings prevented dissolution to different extents due to the various way they were attached to the AgNP surface. Moreover, small, medium, and large sized AgNPs were used to study the size effects on AgNP dissolution. The surrounding medium concentration and temperature were the two variables that were included in the size effects study.
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Sundström, Johanna. "Nanoparticle size-dependent activation of the hemostasis and the innate immune system." Thesis, Uppsala universitet, Institutionen för immunologi, genetik och patologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-298888.

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Nanoparticles are small particles with a size range of 10-1000 nm. They exist all around us, in make-up, dust and even food. They can enter our bloodstream through different pathways such as inhalation and cause thrombosis and multiple organ failure. They can be modified to act as drug deliverers and can treat even hard to reach places because of their small size. Studies have shown that the activation of the coagulation system and complement system is dependent on the size of the nanoparticle. This study’s main focus was to determine if there was a difference in the degree of activation on hemostasis and innate immunity by using four different nanoparticle sizes. The Chandler loop model makes it possible for blood to incubate with the nanoparticles and still be circulating in 37oC similar to the situation in the body. ELISA was thereafter performed on the plasma to determine the concentration of thrombin- antithrombin complex (TAT), C3a and Terminal Complement Complex (TCC). The most activating particles size on the complements system was 260 nm and for the coagulation system it was the 75 nm. FXII assay was performed and the results collaborated with the findings from the ELISA that the smallest particle sizes are most activating on the coagulation system. Taken together, smaller nanoparticle sizes are activating the coagulation system while the bigger nanoparticle sizes are more activating on the complement system. To confirm these results additional research should be performed to statistically confirm the importance of these findings.
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Shen, Christopher. "Effects of surface chemistry and size on iron oxide nanoparticle delivery of oligonucleotides." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/39520.

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The discovery of RNA interference and the increasing understanding of disease genetics have created a new class of potential therapeutics based on oligonucleotides. This therapeutic class includes antisense molecules, small interfering RNA (siRNA), and microRNA modulators such as antagomirs (antisense directed against microRNA) and microRNA mimics, all of which function by altering gene expression at the translational level. While these molecules have the promise of treating a host of diseases from neurological disorders to cancer, a major hurdle is their inability to enter cells on their own, where they may render therapeutic effect. Nanotechnology is the engineering of materials at the nanometer scale and has gained significant interest for nucleic acid delivery due to its biologically relevant length-scale and amenability to multifunctionality. While a number of nanoparticle vehicles have shown promise for oligonucleotide delivery, there remains a lack of understanding of how nanoparticle coating and size affect these delivery processes. This dissertation seeks to elucidate some of these factors by evaluating oligonucleotide delivery efficiencies of a panel of iron oxide nanoparticles with varying cationic coatings and sizes. A panel of uniformly-sized nanoparticles was prepared with surface coatings comprised of various amine groups representing high and low pKas. A separate panel of nanoparticles with sizes of 40, 80, 150, and 200 nm but with the same cationic coating was also prepared. Results indicated that both nanoparticle surface coating and nanoparticle hydrodynamic size affect transfection efficiency. Specific particle coatings and sizes were identified that gave superior performance. The intracellular fate of iron oxide nanoparticles was also tracked by electron microscopy and suggests that they function via the proton sponge effect. The research presented in this dissertation may aid in the rational design of improved nanoparticle delivery vectors for nucleic acid-based therapy.
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Books on the topic "Nanoparticle size"

1

Donnelly, Michelle K. Particle size measurements for spheres with diameters of 50 nm to 400 nm. Gaithersburg, Md: U.S. Dept. of Commerce, Technology Administration, National Institute of Standards and Technology, Building and Fire Research Laboratory, 2003.

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From gold nano-particles through nano-wire to gold nano-layers. New York: Nova Science, 2010.

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Podzimek, Stepan. Light scattering, size exclusion chromatography, and asymmetric flow field flow fractionation: Powerful tools for the characterization of polymers, proteins and nanoparticles. Hoboken, N.J: Wiley, 2011.

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Cardiovascular effects of inhaled ultrafine and nano-sized particles. Hoboken, N.J: Wiley, 2011.

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Netzer, Falko P., and Claudine Noguera. Oxide Thin Films and Nanostructures. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780198834618.001.0001.

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Nanostructured oxide materials ultra-thin films, nanoparticles and other nanometer-scale objects play prominent roles in many aspects of our every-day life, in nature and in technological applications, among which is the all-oxide electronics of tomorrow. Due to their reduced dimensions and dimensionality, they strongly interact with their environment gaseous atmosphere, water or support. Their novel physical and chemical properties are the subject of this book from both a fundamental and an applied perspective. It reviews and illustrates the various methodologies for their growth, fabrication, experimental and theoretical characterization. The role of key parameters such as film thickness, nanoparticle size and support interactions in driving their fundamental properties is underlined. At the ultimate thickness limit, two-dimensional oxide materials are generated, whose functionalities and potential applications are described. The emerging field of cation mixing is mentioned, which opens new avenues for engineering many oxide properties, as witnessed by natural oxide nanomaterials such as clay minerals, which, beyond their role at the Earth surface, are now widely used in a whole range of human activities. Oxide nanomaterials are involved in many interdisciplinary fields of advanced nanotechnologies: catalysis, photocatalysis, solar energy materials, fuel cells, corrosion protection, and biotechnological applications are amongst the areas where they are making an impact; prototypical examples are outlined. A cautious glimpse into future developments of scientific activity is finally ventured to round off the treatise.
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Maysinger, Dusica, P. Kujawa, and Jasmina Lovrić. Nanoparticles in medicine. Edited by A. V. Narlikar and Y. Y. Fu. Oxford University Press, 2017. http://dx.doi.org/10.1093/oxfordhb/9780199533060.013.14.

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This article examines the applications of nanoparticles in medicine. Nanomedicine is a promising field that can make available different nanosystems whose novel, usually size-dependent, physical, chemical and/or biological properties are exploited to combat the disease of interest. One kind of particulate systems represents a vast array of either metallic,semiconductor, polymeric, protein or lipid nanoparticles that can be exploited for diagnosis and treatment of various diseases. This article first provides an overview of general issues related to physicochemical and biological properties of different nanoparticles. It then considers the current problems associated with the use of nanoparticles in medicine and suggests some solutions. It also discusses the interaction of nanoparticles with cells and factors that determine these interactions and concludes with some examples of new approaches for real-time imaging of experimental animals that could be useful, complementary methods for evaluations of effectiveness (or toxicity) of novel nanomaterials andnanomedicines.
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Araújo, Ana Cláudia Vaz de. Síntese de nanopartículas de óxido de ferro e nanocompósitos com polianilina. Brazil Publishing, 2021. http://dx.doi.org/10.31012/978-65-5861-120-2.

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In this work magnetic Fe3O4 nanoparticles were synthesized through the precipitation method from an aqueous ferrous sulfate solution under ultrasound. A 23 factorial design in duplicate was carried out to determine the best synthesis conditions and to obtain the smallest crystallite sizes. Selected conditions were ultrasound frequency of 593 kHz for 40 min in 1.0 mol L-1 NaOH medium. Average crystallite sizes were of the order of 25 nm. The phase obtained was identified by X-ray diffractometry (XRD) as magnetite. Scanning electron microscopy (SEM) showed polydisperse particles with dimensions around 57 nm, while transmission electron microscopy (TEM) revealed average particle diameters around 29 nm, in the same order of magnitude of the crystallite size determined with Scherrer’s equation. These magnetic nanoparticles were used to obtain nanocomposites with polyaniline (PAni). The material was prepared under exposure to ultraviolet light (UV) or under heating, from dispersions of the nanoparticles in an acidic solution of aniline. Unlike other synthetic routes reported elsewhere, this new route does not utilize any additional oxidizing agent. XRD analysis showed the appearance of a second crystalline phase in all the PAni-Fe3O4 composites, which was indexed as goethite. Furthermore, the crystallite size decreases nearly 50 % with the increase in the synthesis time. This size decrease suggests that the nanoparticles are consumed during the synthesis. Thermogravimetric analysis showed that the amount of polyaniline increases with synthesis time. The nanocomposite electric conductivity was around 10-5 S cm-1, nearly one order of magnitude higher than for pure magnetite. Conductivity varied with the amount of PAni in the system, suggesting that the electric properties of the nanocomposites can be tuned according to their composition. Under an external magnetic field the nanocomposites showed hysteresis behavior at room temperature, characteristic of ferromagnetic materials. Saturation magnetization (MS) for pure magnetite was ~ 74 emu g-1. For the PAni-Fe3O4 nanocomposites, MS ranged from ~ 2 to 70 emu g-1, depending on the synthesis conditions. This suggests that composition can also be used to control the magnetic properties of the material.
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Mørup, Steen, Cathrine Frandsen, and Mikkel F. Hansen. Magnetic properties of nanoparticles. Edited by A. V. Narlikar and Y. Y. Fu. Oxford University Press, 2017. http://dx.doi.org/10.1093/oxfordhb/9780199533053.013.20.

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This article discusses the magnetic properties of nanoparticles. It first considers magnetic domains and the critical size for single-domain behavior of magnetic nanoparticles before providing an overview of magnetic anisotropy in nanoparticles. It then examines magnetic dynamics in nanoparticles, with particular emphasis on superparamagnetic relaxation and the use of Mössbauer spectroscopy, dc magnetization measurements, and ac susceptibility measurements for studies of superparamagnetic relaxation. It also describes magnetic dynamics below the blocking temperature, magnetic interactions between nanoparticles, and fluctuations of the magnetization directions. Finally, it analyzes the magnetic structure of nanoparticles, focusing on magnetic phase transitions and surface effects, non-collinear spin structures, and magnetic moments of antiferromagnetic nanoparticles.
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W, Mulholland G., and Building and Fire Research Laboratory (U.S.), eds. Particle size measurements for spheres with diameters of 50 nm to 400 nm. Gaithersburg, Md: U.S. Dept. of Commerce, Technology Administration, National Institute of Standards and Technology, Building and Fire Research Laboratory, 2003.

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Particle size measurements for spheres with diameters of 50 nm to 400 nm. Gaithersburg, Md: U.S. Dept. of Commerce, Technology Administration, National Institute of Standards and Technology, Building and Fire Research Laboratory, 2003.

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Book chapters on the topic "Nanoparticle size"

1

Caizer, Costica. "Nanoparticle Size Effect on Some Magnetic Properties." In Handbook of Nanoparticles, 475–519. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-15338-4_24.

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Caizer, Costica. "Nanoparticle Size Effect on Some Magnetic Properties." In Handbook of Nanoparticles, 1–38. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-13188-7_24-1.

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Iglesias, Òscar, and Hamid Kachkachi. "Single Nanomagnet Behaviour: Surface and Finite-Size Effects." In New Trends in Nanoparticle Magnetism, 3–38. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-60473-8_1.

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Sahu, Puspanjali, Jayesh Shimpi, and B. L. V. Prasad. "Molecular Tools for Controlling Nanoparticle Size/Morphologies." In Molecular Materials, 189–212. Boca Raton, FL : CRC Press, [2017]: CRC Press, 2017. http://dx.doi.org/10.1201/9781315118697-8.

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Zheng, Guangchao, Erjun Liang, and Shenli Wang. "CHAPTER 13. Proteins Engineer the Size and Morphology of Noble Metal Nanoparticles." In Reducing Agents in Colloidal Nanoparticle Synthesis, 333–54. Cambridge: Royal Society of Chemistry, 2021. http://dx.doi.org/10.1039/9781839163623-00333.

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Gomathi, Thandapani, K. Rajeshwari, V. Kanchana, P. N. Sudha, and K. Parthasarathy. "Impact of Nanoparticle Shape, Size, and Properties of the Sustainable Nanocomposites." In Sustainable Polymer Composites and Nanocomposites, 313–36. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-05399-4_11.

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Bażela, Wiesława, Marcin Dul, Andrzej Szytuła, and Volodymyr Dyakonov. "Grain Size Effect on Crystal Microstructure of the Nanoparticle TbMnO3 Manganite." In Springer Proceedings in Physics, 445–56. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-56422-7_33.

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Li, Mingheng, and Panagiotis D. Christofides. "Feedback Control of Particle Size Distribution in Nanoparticle Synthesis and Processing." In Feedback Control of MEMS to Atoms, 7–44. New York, NY: Springer US, 2011. http://dx.doi.org/10.1007/978-1-4419-5832-7_2.

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Royer, F., D. Jamon, J. J. Rousseau, D. Zins, V. Cabuil, S. Neveu, and H. Roux. "Magneto-optical properties of CoFe2O4 ferrofluids. Influence of the nanoparticle size distribution." In Trends in Colloid and Interface Science XVII, 155–58. Berlin, Heidelberg: Springer Berlin Heidelberg, 2004. http://dx.doi.org/10.1007/b94013.

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Hazra Chowdhury, Arpita, Rinku Debnath, Sk Manirul Islam, and Tanima Saha. "Impact of Nanoparticle Shape, Size, and Properties of Silver Nanocomposites and Their Applications." In Sustainable Polymer Composites and Nanocomposites, 1067–91. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-05399-4_37.

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Conference papers on the topic "Nanoparticle size"

1

Qiu, Jinghan, and Jie Fu. "Conditions that Influence Nanoparticle Size and Yield in Nanoparticle Preparation." In ICBET 2020: 2020 10th International Conference on Biomedical Engineering and Technology. New York, NY, USA: ACM, 2020. http://dx.doi.org/10.1145/3397391.3397419.

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Cody, Jonathan W., and Sungwon S. Kim. "Effects of Annealing Parameters on Nickel Catalyst Nanoparticle Size for Carbon Nanotube Synthesis Applications." In ASME 2016 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/imece2016-65514.

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The properties of carbon nanotubes are dependent, in part, on the size of the catalyst metal nanoparticles from which the carbon nanotubes are grown. Annealing is a common technique for forming the catalyst nanoparticles from deposited films. While there is ample work connecting catalyst film properties or catalyst nanoparticle properties to carbon nanotube growth outcomes, the control of catalyst nanoparticle size by means other than the variation of initial film thickness is less explored. This work develops an empirical correlation for the control of nickel nanoparticle equivalent diameter by modification of anneal plateau temperature and anneal plateau time, thereby providing an additional avenue of control for catalyst properties. It has been hypothesized that the size of catalyst nanoparticles can be predetermined by appropriate selection of the initial catalyst film thickness, plateau temperature, and plateau time of the annealing process. To this end, buffer layers of 50 nm titanium, followed by 20 nm aluminum, were deposited onto silicon substrates via electron beam evaporation. Nickel catalyst layers were then deposited with thicknesses of either 5, 10, or 20 nm. Samples of each of the three nickel layer thicknesses were annealed in an ambient air environment at different combinations of 500, 600, 700, 800, and 900 °C plateau temperature and 5, 10, and 15 minute plateau time. Representative time-temperature curves corresponding to each plateau temperature were also acquired. The end result was a set of 45 samples, each with a unique combination of initial nickel film thickness, anneal plateau temperature, and anneal plateau time. Resulting nanoparticles were characterized by atomic force microscopy, and distributions of nanoparticle equivalent diameter were collected via a watershed algorithm implemented by the Gwyddion software package. Comparison of the 45 parameter combinations revealed a wide range of nanoparticle sizes. In most cases, comparable equivalent diameters were obtained from a variety of parameter combinations. Thus, results provide multiple options for achieving the same nanoparticle diameter, for use in cases where additional restraints are present. To facilitate such decisions, a correlation was developed that connected catalyst nanoparticle diameter to the three process parameters of initial catalyst film thickness, anneal plateau temperature, and anneal plateau time. For example, a given initial Ni film thickness can be annealed to a specified nanoparticle size by selecting anneal plateau temperature and plateau time per the correlation, provided that comparable buffer layers were chosen. This correlation provides a more robust array of options for specification of catalyst nanoparticle size and final carbon nanotube properties for a specific application.
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Jurney, Patrick, Rachit Agarwal, Vikramjit Singh, Krishnendu Roy, S. V. Sreenivasan, and Li Shi. "The Effect of Nanoparticle Size on Margination and Adhesion Propensity in Artificial Micro-Capillaries." In ASME 2012 Third International Conference on Micro/Nanoscale Heat and Mass Transfer. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/mnhmt2012-75258.

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Intravenous injection of nanoparticles as drug delivery vehicles is a common practice used in in-vivo and clinical trials of therapeutic agents to target specific cancerous or pathogenic sites. The vascular flow dynamics of nanocarriers in human capillaries play an important role in the ultimate efficacy of this drug delivery method. This article reports an experimental study of the effect of nanoparticle size on their margination and adhesion propensity in micro fabricated microfluidic channels of a half elliptical cross-section. Spherical polystyrene particles ranging in diameter from 60 to 970 nm were flown in the microchannels and individual particles adhered to either the channel’s top or bottom wall were imaged using fluorescence microscopy. The results show a significant increase in adhesion for particles with diameter below 200 nm as well as the emergence of a critical nanoparticle diameter of about 970 nm, where no nanoparticle adherence was observed on the top wall. For the same particle number concentration, the total volume of the nanoparticles adhered to the top and bottom walls was found to increase with decreasing diameter for diameters less than 200 nm. The results are explained by the competition between Brownian motion, gravity and hemodynamic forces on the nanoparticles. These findings on the flow behavior of spherical nanoparticles in artificial micro-capillaries provide further insight for the rational design of nanocarriers for targeted cancer therapeutics.
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Yu, Qun, Chao Zhu, Robert Pfeffer, and Rajesh N. Dave. "Experimental Study on Fluidization Characteristics of Nanoparticles." In ASME 2004 Heat Transfer/Fluids Engineering Summer Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/ht-fed2004-56269.

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Recent studies show that nano-sized particles can be fluidized in the form of nanoparticle agglomerates. However, fluidization behavior such as the minimum fluidization velocity and fluidization regime differ significantly for different nanoparticles. Hence this paper is aimed to experimentally investigate the general fluidization characteristics of different nanoparticles. It is interesting to note that a fluidized bed of nanoparticle agglomerates is optically semi-transparent due to the extremely high porosity (typically over 99%) of the bed with respect to the primary materials of nanoparticles. Taking advantage of this unique feature, traditional optical measurement techniques are applied to visualize the flow structure as well as to measure the size of the fluidizing nanoparticle agglomerates. Based on measurements of four different nanoparticle materials, two types of fluidization behavior have been identified, which closely resemble those of classical Geldart Group A and Group B particles, respectively. It shows, however, that the bed of “Group A” nanoparticles expands as long as there is a flow through the bed, which is different from the classical fluidization of Geldart Group A particles where there is no bed expansion until reaching the minimum fluidization velocity. It is also noted that, based on the apparent density and size, the fluidization behavior of nanoparticle agglomerates do not precisely follow the Geldart classification. To differentiate these particles with very similar fluidization characteristics, terms the APF and ABF are introduced for the fluidization classification of nanoparticle agglomerates. Typical fluidization characteristics including bed expansion, bed pressure drop and hysteresis effects of both APF and ABF nanoparticles. The sizes of nanoparticle agglomerates also have been measured using an in-situ optical measurement system.
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Devaraj, Harish, Hyun-Jun Hwang, and Rajiv Malhotra. "Effect of Size Distribution on Optical Absorption During Intense Pulsed Light Sintering of Metal Nanoparticles." In ASME 2018 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/imece2018-87038.

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Intense pulsed light sintering (IPL) of nanoparticles on rigid or flexible substrates enables rapid fabrication of thin films and patterns over large areas. In IPL, visible light from a high energy xenon lamp is absorbed by the nanoparticles for rapid sintering of metallic and non-metallic nanoparticles. This plasmonic optical absorption during the process for metal nanoparticles has been shown to depend on individual nanoparticle size. However, but there is little understanding of how this absorption depends on nanoparticle size distribution during IPL. This work incorporates a fully three-dimensional packing model along with an electromagnetic model of plasmonic absorption in silver nanoparticles to bridge this gap. It is shown that smaller standard deviation in a unimodal distribution and smaller size ratios in a bimodal distribution demonstrate relatively higher optical absorption in IPL.
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OLIVEIRA, E. M., J. A. CASTRO, I. C. R. P. VALADÃO, and A. S. F. ARAÚJO. "CHARACTERISATION OF NANOPARTICLE SIZE OF TIO2 USING NANOPARTICLE TRACKING ANALYSIS (NTA)." In XX Congresso Brasileiro de Engenharia Química. São Paulo: Editora Edgard Blücher, 2015. http://dx.doi.org/10.5151/chemeng-cobeq2014-0768-24092-152900.

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Kikitsu, T., Y. Yagoto, M. Ogawa, and H. Yagyu. "Laser microfabrication of gold nanoparticles dispersed polymer film with nanoparticle size control." In TRANSDUCERS 2015 - 2015 18th International Solid-State Sensors, Actuators and Microsystems Conference. IEEE, 2015. http://dx.doi.org/10.1109/transducers.2015.7181317.

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Mirkoohi, Elham, and Rajiv Malhotra. "Effect of Particle Shape on Neck Growth and Shrinkage of Nanoparticles." In ASME 2017 12th International Manufacturing Science and Engineering Conference collocated with the JSME/ASME 2017 6th International Conference on Materials and Processing. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/msec2017-2811.

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Sintering of nanoparticles to create films and patterns of functional materials is emerging as a key manufacturing process in applications like flexible electronics, solar cells and thin-film devices. Further, there is the emerging potential to use nanoparticle sintering to perform additive manufacturing as well. While the effect of nanoparticle size on sintering has been well studied, very little attention has been paid to the effect of nanoparticle shape on the evolution of sintering. This paper uses Molecular dynamics (MD) simulations to determine the influence of particle shape on shrinkage and neck growth for two common nanoparticle shape combinations, i.e., sphere-sphere and sphere-cylinder nanoparticles of different sizes. These sintering indicators are examined at two different temperature ramps. The results from this work show that depending on their relative sizes, degree of neck growth and shrinkage are both significantly affected by the nanoparticle shape. The possibility of using this phenomenon to control density and stresses during nanoparticle sintering are discussed.
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Coleman, Joshua P., and A. G. Agwu Nnanna. "Nanoparticle Deposition and Convective Transport in Microchannel Heat Exchanger Systems." In ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-62957.

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In the absence of dispersants, surfactants or other deposition inhibiting techniques, nanoparticles contained in a base fluid could potentially deposit on channel walls. Nanoparticle layering has been shown to impact heat transfer coefficient, alter hydrodynamic characteristics including viscosity and flow regime, and influence the onset of boundary layers. The rate of deposition is a function of nanoparticle size, heat flux, microchannel hydraulic diameter, fluid velocity, temperature, adhesion properties and volume fraction. This paper presents an analytical investigation of nanoparticle deposition in microchannel heat exchanger systems. The objective of this study is to correlate the rate of deposition with nanoparticle size, microchannel hydraulic diameter, heat flux and volume fraction for transient flow conditions in which Brownian diffusion and thermophoresis are appreciable slip mechanisms of nanoparticle transport. A two-component four-equation nonhomogeneous thermal equilibrium model for mass, momentum and energy in nanofluids that includes nanoparticle mass transport into the channel walls is used in this analysis. An analytical model representing the transient distribution of nanoparticles in a channel is proposed.
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Otanicar, Todd, Robert A. Taylor, Patrick E. Phelan, and Ravi Prasher. "Impact of Size and Scattering Mode on the Optimal Solar Absorbing Nanofluid." In ASME 2009 3rd International Conference on Energy Sustainability collocated with the Heat Transfer and InterPACK09 Conferences. ASMEDC, 2009. http://dx.doi.org/10.1115/es2009-90066.

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The concept of using a direct absorbing nanofluid, a liquid-nanoparticle suspension, has recently been shown numerically and experimentally to be an efficient method for harvesting solar thermal energy. Studies show that the size and shape of the nanoparticles as well as the scattering mode (e.g. dependent, independent, and multiple) all impact the amount of energy absorbed and emitted by the nanofluid. In order to optimize the efficiency of a direct absorption solar thermal system the optimum nanoparticle-liquid combination needs to be developed. The optimum nanofluid for a direct absorption solar thermal collector is investigated numerically through the variation of particle size, including the impact of size on optical properties, and scattering mode. The study addresses both the absorption of solar energy within the fluid as well as the emission of the fluid.
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Reports on the topic "Nanoparticle size"

1

Brechtel, Fredrick J. Compact Nanoparticle Size Distribution Measurement System for Unmanned Aerial Systems (UAS). Office of Scientific and Technical Information (OSTI), July 2017. http://dx.doi.org/10.2172/1371927.

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Thomson, T. Silicide formation and particle size growth in high temperature annealed, self-assembled FePt nanoparticle arrays. Office of Scientific and Technical Information (OSTI), October 2003. http://dx.doi.org/10.2172/826528.

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Kuang, C., P. Artaxo, S. Martin, and J. Wang. Observations and Modeling of the Green Ocean Amazon 2014/15. Nanoparticle Size Distribution (NPSD) Field Campaign Report. Office of Scientific and Technical Information (OSTI), April 2016. http://dx.doi.org/10.2172/1248489.

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Mohar, Jacob Steven, Ekaterina Dolgopolova, and Jennifer Ann Hollingsworth. Size and Shape Control of Gallium-Iron Oxide Nanoparticles. Office of Scientific and Technical Information (OSTI), July 2019. http://dx.doi.org/10.2172/1545738.

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Koski, Kristie Jo. Size-dependent structure of silver nanoparticles under high pressure. Office of Scientific and Technical Information (OSTI), December 2008. http://dx.doi.org/10.2172/978860.

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Zook, Justin M., Robert MacCuspie, John T. Elliott Jr., and Elijah J. Petersen. Reliable preparation of nanoparticle agglomerates of different sizes in cell culture media. National Institute of Standards and Technology, June 2015. http://dx.doi.org/10.6028/nist.sp.1200-14.

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Hackley, Vincent A. Measuring the Size of Nanoparticles in Aqueous Media Using Batch-Mode Dynamic Light Scattering. National Institute of Standards and Technology, May 2015. http://dx.doi.org/10.6028/nist.sp.1200-6.

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Underwood, Samuel J., and Justin M. Gorham. Challenges and approaches for particle size analysis on micrographs of nanoparticles loaded onto textile surfaces. Gaithersburg, MD: National Institute of Standards and Technology, May 2017. http://dx.doi.org/10.6028/nist.sp.1200-22.

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