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Search for "diffusion" in Full Text gives 662 result(s) in Beilstein Journal of Nanotechnology. Showing first 200.
Sidewall angle tuning in focused electron beam-induced processing
Beilstein J. Nanotechnol. 2024, 15, 447–456, doi:10.3762/bjnano.15.40
- deposit. In addition, the dissociation of the precursor molecules needs to be modelled, secondary reactions of the etch products need to be taken into account, also the residence time of the fragments on the deposit, the sticking and diffusion of the water molecules, and so on. Although this is a very
- the etching takes place is unknown. It was noticed that a small change in the pressure of water vapour led to a significant change in the etching rate, suggesting that the process is gas-limited (see Supporting Information File 1, section S3). The role of diffusion could therefore be significant. The
- diffusion rate of adsorbed contamination is known to be enhanced by the presence of water layers [21]. But since the relevant quantities are hard to measure, the diffusion rate has not been included in the model, nor have some other factors such as scattering, porosity, and secondary etch product reactions
Heat-induced morphological changes in silver nanowires deposited on a patterned silicon substrate
Beilstein J. Nanotechnol. 2024, 15, 435–446, doi:10.3762/bjnano.15.39
- fragmentation of NWs is attributed to the interplay between heat-enhanced diffusion and Rayleigh instability. In this work, we demonstrated that contact with the substrate plays an important role in the fragmentation process and can strongly affect the outcome of the heat treatment. We deposited silver NWs onto
- process, fragmentation in either adhered or suspended parts can dominate. Experiments were supported by finite element method and molecular dynamics simulations. Keywords: diffusion; finite element method; heat treatment; molecular dynamics simulations; morphological changes; scanning electron microscopy
- . However, during prolonged heat treatment (lasting minutes or more), surface atom diffusion can lead to morphological changes in NWs even at temperatures several hundred degrees below the melting point of the material [26][27]. Sintering of Ag and Au NWs at intersections can occur at temperatures as low as
Investigating ripple pattern formation and damage profiles in Si and Ge induced by 100 keV Ar+ ion beam: a comparative study
Beilstein J. Nanotechnol. 2024, 15, 367–375, doi:10.3762/bjnano.15.33
- Harper [31] based on morphological effects of IBS. The height h(x, y, t) of the sputtered surface can be described by a linear equation (Equation 1): where ν0 is the constant erosion velocity, ν is the effective surface tension, and D denotes the surface diffusion which is activated by different physical
- processes (i.e., thermal diffusion and ion-induced diffusion) [32]. This approach is based on the linear cascade model and Gaussian approximation of energy distribution as developed by Sigmund [26] to describe ion–atom collisions inside the target. Rutherford backscattering spectrometry (RBS) studies in the
- diffusion processes. The values for α and β were found to be α = 0.42 and 0.26 and β = 0.23 and 0.19 for Si and Ge, respectively, indicating that sputtering dominates in both cases to create ripples on the two surfaces. However, this process is better for Si. Transmission electron microscopy studies The TEM
Exploring the relationships between physiochemical properties of nanoparticles and cell damage to combat cancer growth using simple periodic table-based descriptors
Beilstein J. Nanotechnol. 2024, 15, 297–309, doi:10.3762/bjnano.15.27
- unstable and tend to agglomerate. NPs attract negative or positive ions from the medium to build a diffusion double layer. The electronegativity of the NPs also depends on the pH value of the medium [40]. In colloidal solutions, negatively charged metal oxides decrease the zeta potential, which reflects
Multiscale modelling of biomolecular corona formation on metallic surfaces
Beilstein J. Nanotechnol. 2024, 15, 215–229, doi:10.3762/bjnano.15.21
- rate of collisions between two spheres in solution, normalized by the number of binding sites for that protein, where RNP is the radius of the NP, NA is Avogadro’s number, RA is the effective adsorbate radius, D is the pair diffusion coefficient given by taking the viscosity η = 8.9 × 10−4 Pa·s. We
Graphene removal by water-assisted focused electron-beam-induced etching – unveiling the dose and dwell time impact on the etch profile and topographical changes in SiO2 substrates
Beilstein J. Nanotechnol. 2024, 15, 190–198, doi:10.3762/bjnano.15.18
- is dependent on the precursor dynamics (adsorption/desorption rate, diffusion), electron beam (lateral size, electron flux, energy), and scanning parameters (dwell time, refresh time, scanning strategy) [22]. Additionally, residual hydrocarbons inside the scanning electron microscope chamber manifest
Development and characterization of potential larvicidal nanoemulsions against Aedes aegypti
Beilstein J. Nanotechnol. 2024, 15, 104–114, doi:10.3762/bjnano.15.10
- a transport exponent value (n) of 0.3, indicating a release mechanism primarily driven by Fickian diffusion [44]. The free terpenes exhibited a value of 0.6, suggesting an anomalous transport mechanism for drug release. This mechanism involves a combination of diffusion and dissolution processes for
- conditions. Modified Franz cells, equipped with a polyethersulfone membrane (Sigma-Aldrich) and with a diffusion area of 1.77 cm2 were used in the assays. A Microette (Hanson Research, USA) was used. The receptor compartment was filled with 7.0 mL of a receptor solution composed of 0.1 M phosphate buffer and
Berberine-loaded polylactic acid nanofiber scaffold as a drug delivery system: The relationship between chemical characteristics, drug-release behavior, and antibacterial efficiency
Beilstein J. Nanotechnol. 2024, 15, 71–82, doi:10.3762/bjnano.15.7
- nanofiber compositions [11][12][13]. For a long-term drug release, hydrophobic polymers are chosen for the preparation of drug-loaded nanofiber scaffolds. This is because the hydrophobicity of the polymer could form air gaps, slowing matrix hydration and suppressing drug diffusion from the nanofibers [14
- compared to that of other models. In addition, the release exponent (n) of the equation was 0.1703, indicating that the BBR release from the BBR/PLA nanofiber scaffold followed the Fickian diffusion. In this mechanism, the release of BBR was governed by a diffusion process, where the diffusion rate was
- higher than the polymer relaxation [43]. Based on the R2 values shown in Table 1, the release data of the BBR NPs/PLA nanofiber scaffold was simultaneously well described by the Higuchi and Ritger–Peppas models, suggesting that BBR NPs release was mainly controlled by a diffusion mechanism. However, the
Influence of conductive carbon and MnCo2O4 on morphological and electrical properties of hydrogels for electrochemical energy conversion
Beilstein J. Nanotechnol. 2024, 15, 57–70, doi:10.3762/bjnano.15.6
- the morphology also facilitates the penetration by the electrolyte, the diffusion of ions to electroactive sites, and the rapid release of the reaction, thus promoting the kinetics of the reaction and achieving higher efficiency of the catalyst built into the 3D structure [19]. The hydrogel matrix
- designed to facilitate and increase mass transport; therefore, it is vital to achieve the desired three-dimensional structure of the material. In addition, the free space in the form of pores and the network structure within the polymer facilitate the penetration by the electrolyte, the diffusion of ions
- scaffold, coating its surface. The characteristic porous structure is still formed but has a much more granular structure. The presence of pores is very important in the case of the application of hydrogel composite in OER. As aforementioned, the porosity has a beneficial effect on the diffusion of
Nanotechnological approaches in the treatment of schistosomiasis: an overview
Beilstein J. Nanotechnol. 2024, 15, 13–25, doi:10.3762/bjnano.15.2
- polymers or the polymerization of monomers [17]. The first one is more commonly describe in the literature, and the techniques usually employed to produce them include nanoprecipitation, solvent evaporation, emulsification/solvent diffusion, and emulsification/reverse salting out [18][19]. The main
- homogenization); (2) low-energy methods, which requires the precipitation of nanoparticles from homogeneous systems (such as microemulsions); and (3) methods based on organic solvents (emulsification–diffusion method) [35]. Liposomes are vesicles composed of a phospholipid and cholesterol with an aqueous core
unDrift: A versatile software for fast offline SPM image drift correction
Beilstein J. Nanotechnol. 2023, 14, 1225–1237, doi:10.3762/bjnano.14.101
- effective way to reduce thermal drift to a minimum is to carry out SPM experiments under cryogenic conditions close to the temperature of liquid helium. The cryogenic temperature, however, also drastically reduces the rates of thermal processes such as on-surface reactions, diffusion, or desorption [25
Elasticity, an often-overseen parameter in the development of nanoscale drug delivery systems
Beilstein J. Nanotechnol. 2023, 14, 1149–1156, doi:10.3762/bjnano.14.95
- filled with poly(lactic-co-glycolic acid) (PLGA) cores of different sizes resulting in interfacial water layers with different thicknesses and therefore with tunable elasticity [38]. Semielastic particles whose Young’s moduli were around 50 mPa showed the fastest diffusion in mucus. However, harder
- the interaction with mucus in vitro, they demonstrated that the apparent permeability coefficient (Papp value) through porcine intestinal mucus as well as the diffusion determined by particle tracking is significantly higher for softer particles. However, as soon as cells are included in the system
Dual-heterodyne Kelvin probe force microscopy
Beilstein J. Nanotechnol. 2023, 14, 1068–1084, doi:10.3762/bjnano.14.88
- dynamics is indeed the effective mobility of holes and electrons (under the effect of drift diffusion) in the donor and acceptor networks. After the application of a light pulse – and during the duration of the pulse – the charge mobility limits the rate at which an electrostatic equilibrium can be reached
Nanoarchitectonics of photothermal materials to enhance the sensitivity of lateral flow assays
Beilstein J. Nanotechnol. 2023, 14, 988–1003, doi:10.3762/bjnano.14.82
- photothermal LFA (A). Comparison of Pe and Da on the LFA membrane. (Pe, the ratio between diffusion time and convection time), (Da, ratio between diffusion flux and reaction flux) (B). Comparison of visual and thermal signal (A, B and C stand for 100, 60, 30 nm sized GNP respectively: A, B and C correspond to
Isolation of cubic Si3P4 in the form of nanocrystals
Beilstein J. Nanotechnol. 2023, 14, 971–979, doi:10.3762/bjnano.14.80
- precursor for diffusion doping of wafers and as anode material for Li-ion batteries. A similar method with a hydrogenation step offers the possibility to obtain other compounds, such as silicon selenides, arsenides, and sulfides. Keywords: ampoule annealing; defective zinc blende structure; DFT
- microcircuits through the introduction of P donors by diffusion doping of wafers with an efficiency comparable to monolayer doping [18] or ion implantation [19]. This paper outlines the successful formation of the cubic Si3P4 phase under mild conditions. The technique developed for this investigation requires
- phosphorus as a dopant. From the outset, phosphorus diffusion through hydrogenated and oxide layers was surmised to be different. In the case of similar previously performed syntheses of Si NPs with an oxide layer [21], phosphorus diffuses deep into the NP cores and distributes rather homogenously with a
Low temperature atomic layer deposition of cobalt using dicobalt hexacarbonyl-1-heptyne as precursor
Beilstein J. Nanotechnol. 2023, 14, 951–963, doi:10.3762/bjnano.14.78
- resistance to electromigration and lowers the tendency to undergo diffusion, giving a higher stability in environments involving both elevated temperature and high current densities [1][3]. In current technology nodes with device dimensions below 10 nm, electron scattering becomes the dominant factor in
Antibody-conjugated nanoparticles for target-specific drug delivery of chemotherapeutics
Beilstein J. Nanotechnol. 2023, 14, 912–926, doi:10.3762/bjnano.14.75
- antigen binding ability. Improper antibody conjugation influences antigen binding affinity and specificity. Once injected into the body, the ACNPs face both physical and biological barriers (such as diffusion, flow and shear forces, aggregation, protein adsorption, phagocytic sequestration, and clearance
Nanostructured lipid carriers containing benznidazole: physicochemical, biopharmaceutical and cellular in vitro studies
Beilstein J. Nanotechnol. 2023, 14, 804–818, doi:10.3762/bjnano.14.66
- –Peppas model, also called power law, was initially used to describe drug release in polymeric systems where the two predominant mechanisms were relaxation of the polymer chains and diffusion. In this model (Equation 2), Mt/M∞ is the fraction dissolved, K is a constant that incorporates structural and
- release can be inferred through the value of the release exponent n. For spherical systems, n will take a value of 0.43 for drug release governed by Fickian diffusion, a value of 1 for zero-order release, and intermediate values for intermediate behavior, often regarded as anomalous transport. In our case
- , the estimated value of n was 0.56, suggesting mixed release mechanisms at play with a strong contribution of diffusion. As in our case there is no polymer relaxation involved, it may be hypothesized that the burst effect could be slightly affecting the global kinetics of the process [35]. Although
Silver-based SERS substrates fabricated using a 3D printed microfluidic device
Beilstein J. Nanotechnol. 2023, 14, 793–803, doi:10.3762/bjnano.14.65
- reactants in segmented flow and oil in continuous flow. They can control the reaction rates by mass transfer through convection and diffusion [20][21]. Furthermore, droplet-based microfluidic devices are frequently utilized to synthesize complex materials of uniform size, as each droplet can function as a
Silver nanoparticles loaded on lactose/alginate: in situ synthesis, catalytic degradation, and pH-dependent antibacterial activity
Beilstein J. Nanotechnol. 2023, 14, 781–792, doi:10.3762/bjnano.14.64
- microbial strains S. aureus (Gram-positive) and S. typhi (Gram-negative) using the disk diffusion method at different pH values. To establish the bioactivity of the nanocomposite, antibacterial assays were also conducted in media with different pH values without the nanocomposite. These resulted in no
- to experiment antibacterial activity. The solutions with pH 4, 6, and 12 were also used to determine stability of the nanocomposite through zeta potential measurements and TEM. The disk diffusion method was employed to assay the antibacterial activity of the samples [52]. In order to conduct the
In situ magnesiothermic reduction synthesis of a Ge@C composite for high-performance lithium-ion batterie anodes
Beilstein J. Nanotechnol. 2023, 14, 751–761, doi:10.3762/bjnano.14.62
- the low-frequency region. The former component is characteristic of charge transfer resistance, while the latter presents the diffusion of ions in the solid phase. Compared to the pure Ge electrode, the diameters of the semicircle are smaller in the Ge@C electrodes because of the higher electrical
- elements (CPE) [65]. According to Table 2, the charge transfer resistances of all Ge@C electrodes are much lower than the values of the pure Ge electrode, and Ge/C-iM750 exhibits the lowest value. The ionic conductivity was evaluated using the lithium-ion diffusion coefficient () using the following
Control of morphology and crystallinity of CNTs in flame synthesis with one-dimensional reaction zone
Beilstein J. Nanotechnol. 2023, 14, 741–750, doi:10.3762/bjnano.14.61
- difficult to achieve in a highly heterogeneous environment. Therefore, the analysis of the properties of the reaction zone within the flame is critical for the optimal growth of CNTs. In the present study, a comprehensive comparison between the CNT synthesis using a methane diffusion flame and a premixed
- significant difference in temperature distribution between the two flames causes a difference in the characteristics of the growth products. In the diffusion flame, the growth is limited to specific regions at certain height-above-burner (HAB) values with a temperature range of 750 to 950 °C at varying radial
- control to achieve stable growth conditions. Yet, achieving independent parametric control in flame synthesis is a challenging task. In a diffusion flame, specific locations within the flame are imperative and conducive for CNT growth, depending on height above burner (HAB), local distance from the flame
Cross-sectional Kelvin probe force microscopy on III–V epitaxial multilayer stacks: challenges and perspectives
Beilstein J. Nanotechnol. 2023, 14, 725–737, doi:10.3762/bjnano.14.59
- 1 × 1018 cm−3. The three Zn doping levels of InP layers were purposely inverted along the growth direction to facilitate electrochemical capacitance–voltage (ECV) characterization due to the strong Zn diffusion. The InP:Zn and the GaInAsP:Zn layers were epitaxially grown at a surface temperature of
- KELSCAN [13], which evaluates the contact potential and surface photovoltage as a function of the position. The Silvaco ATLAS model solves the Poisson equation self-consistently coupled to carrier continuity and transport equations in the well-known drift diffusion model, which is given detail in [22] and
- space charge that extends for around 0.16 μm inside the first InP:Zn region. As a matter of fact, the diffusion of Zn impurities is likely to occur due to the high temperatures required for the growth of the material and the high diffusion coefficient of Zn in InP [30]. Therefore, the true spatial
A graphene quantum dots–glassy carbon electrode-based electrochemical sensor for monitoring malathion
Beilstein J. Nanotechnol. 2023, 14, 701–710, doi:10.3762/bjnano.14.56
- the electrode are diffusion-controlled, and the linear relationship (R2 = 0.9674) between peak height and scan rate suggests an enhanced electrochemical activity. Electrochemical detection of malathion Using the modified working GQDs/GCE electrode as electrochemical sensor, a differential pulse
Humidity-dependent electrical performance of CuO nanowire networks studied by electrochemical impedance spectroscopy
Beilstein J. Nanotechnol. 2023, 14, 683–691, doi:10.3762/bjnano.14.54
- , e.g., RH 73% and 95%, Figure 2a). A small tail at low frequencies (RH 95%, Figure 2a inset) corresponds to the appearance of a Warburg element W in the equivalent circuit (Figure 2b), which may be attributed to diffusion processes from liquids at high humidity. The values of impedance magnitude and
- the physisorbed water layer grows [27][32]. At RH above 60% (Figure 4b) the Warburg element appears and it grows with increasing the humidity, which suggests increased contribution of the diffusion processes to the total impedance with increased thickness of the water layer adsorbed at the nanowire
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