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Search for "numerical simulation" in Full Text gives 49 result(s) in Beilstein Journal of Nanotechnology.
Ferromagnetic resonance spectra of linear magnetosome chains
Beilstein J. Nanotechnol. 2024, 15, 157–167, doi:10.3762/bjnano.15.15
- nanoparticles; numerical simulation; Introduction Magnetotactic bacteria are living organisms that grow within themselves magnetite nanoparticles called magnetosomes [1][2][3][4]. In contrast to chemically synthesized magnetite nanoparticles [5][6], magnetosomes have a perfect crystal structure, a narrow size
- [1][2][3][4][7][8][9][16][17][18][19][20][21][22][23] accumulated to date for assemblies of magnetosome chains. Numerical Simulation Consider a dilute assembly of linear chains of magnetosomes consisting of Np spherical nanoparticles of average diameter D. Dynamics of the unit magnetization vector
- resolved for angles θ ≥ 75°. To summarize the numerical simulation data obtained for oriented assemblies, in Figure 3a we show the angle dependence of the resonance FMR field, Hres(θ), for linear chains with various average particle diameters. It is interesting to note the noticeable dependence of the
Measurements of dichroic bow-tie antenna arrays with integrated cold-electron bolometers using YBCO oscillators
Beilstein J. Nanotechnol. 2024, 15, 26–36, doi:10.3762/bjnano.15.3
- of numerical simulation. The aim of the optimization was to bring the absorption bandwidth in line with the current requirements for the LSPE receiving system. According to these requirements, the width of the absorption line should be 20% of the operating frequency for the 210 GHz channel and 10% of
Biomimetics on the micro- and nanoscale – The 25th anniversary of the lotus effect
Beilstein J. Nanotechnol. 2023, 14, 850–856, doi:10.3762/bjnano.14.69
- suspension feeding in common Crustacea. The results show that a system combining long and short setae with different mechanical properties has the best performance. The numerical simulation can in future be easily adapted to other systems and therefore be used for biomimetic developments (e.g., in the field
Specific absorption rate of randomly oriented magnetic nanoparticles in a static magnetic field
Beilstein J. Nanotechnol. 2023, 14, 485–493, doi:10.3762/bjnano.14.39
- in the vicinity of the FFP has been obtained considering an inhomogeneous dc magnetic field created by two opposite magnetic fluxes, for the case of assemblies with different nanoparticle size distributions. Results and Discussion Numerical simulation Let us consider a dilute assembly of magnetic
- combined action of ac and dc magnetic fields is studied using a numerical simulation based on the solution of the stochastic Landau–Lifshitz equation [17][20][22][23][26]. The SAR of a randomly oriented assembly is calculated in terms of the area of the dynamic hysteresis loop according to the well-known
A distributed active patch antenna model of a Josephson oscillator
Beilstein J. Nanotechnol. 2023, 14, 151–164, doi:10.3762/bjnano.14.16
- direct numerical simulation of the sine-Gordon Equation 3 for up and down current sweep. The red line shows the analytic solution with the excess current given by Equation 24. The agreement between exact (without linearization) numeric and (approximate) analytic solutions is quite good. It is seen that a
Numerical study on all-optical modulation characteristics of quantum cascade lasers
Beilstein J. Nanotechnol. 2022, 13, 1011–1019, doi:10.3762/bjnano.13.88
- by Equation 4 and Equation 3, respectively. The numerical methods solving FRE are excellently recorded in [18]. By taking into account the effects of optical injection [19] and electron temperature [20][21], the full rate equation is modified to obtain a more accurate numerical simulation of the
- , and the modulation frequency can reach 60 GHz [13]. Moreover, all-optical modulation can directly alter the carrier distribution and is highly efficient. However, the mechanism of all-optical modulation is very complex. If we could effectively describe all-optical modulation of QCLs by numerical
- simulation, it would be very helpful for optimizing its use and dielectric nanostructure design. Although there has been much research on all-optical modulation of QCLs, only optical injection locking [14] and quenching [15][16] can currently provide one-sided numerical support. Based on the classical 1
Numerical modeling of a multi-frequency receiving system based on an array of dipole antennas for LSPE-SWIPE
Beilstein J. Nanotechnol. 2022, 13, 865–872, doi:10.3762/bjnano.13.77
- for CEB at high frequencies. In the process of numerical simulation, we calculated the dependence of the power, Pi, released on the active resistance of the i-th RC-chain of the array of receiving cells, on the frequency of the incident radiation, and the total power in all receiving cells: The
A broadband detector based on series YBCO grain boundary Josephson junctions
Beilstein J. Nanotechnol. 2022, 13, 325–333, doi:10.3762/bjnano.13.27
- –frequency characteristic, beam pattern, and fraction of the absorbed power in each Josephson junction were investigated. Based on the obtained results, a numerical simulation of one-dimensional arrays was carried out. The dc characteristics of the detector were calculated, that is, current–voltage
- the electromagnetic analysis and numerical simulation of the broadband detector based on a series of HTSC bicrystal Josephson junctions to maximize response, power dynamic range, and noise-equivalent power. Electromagnetic Simulation Figure 1a–c shows options for the geometry of a log-periodic antenna
Heating ability of elongated magnetic nanoparticles
Beilstein J. Nanotechnol. 2021, 12, 1404–1412, doi:10.3762/bjnano.12.104
- of magnitude with an increase in the volume fraction of nanoparticles in a cluster in the range of 0.04–0.2. Keywords: elongated magnetic nanoparticles; magnetic hyperthermia; numerical simulation; specific absorption rate; Introduction Magnetic nanoparticle assemblies have great potential for the
- with an increase in the particle volume fraction in a cluster in the range η = 0.04–0.2. Numerical Simulation In this work the magnetic properties of various assemblies of elongated spheroidal magnetite nanoparticles with different aspect ratios a/b > 1 are studied by means of numerical simulation. It
- cubic [25] magnetic anisotropy showed the existence of an interval of optimal nanoparticle diameters where the SAR of the assembly reaches a maximum at a given frequency and amplitude of an ac magnetic field. In this work, using numerical simulation, similar results were obtained for spheroidal
Cantilever signature of tip detachment during contact resonance AFM
Beilstein J. Nanotechnol. 2021, 12, 1286–1296, doi:10.3762/bjnano.12.96
- photodiode amplitude signal in units of μrad to a numerical simulation of the cantilever response driven by moment couples of different magnitudes. Figure 1c shows the maximum deflection of the cantilever about static equilibrium for the numerical simulations. The dashed grey line in this Figure indicates
- measurements. We also explore the aggregate numerical simulation data of Figure 1 by way of the phase space representation in Figure 3. The phase space has as many dimensions as state variables, but we restrict our viewing to the dominant contributors of the first three basis function modal coordinates
In situ transport characterization of magnetic states in Nb/Co superconductor/ferromagnet heterostructures
Beilstein J. Nanotechnol. 2021, 12, 913–923, doi:10.3762/bjnano.12.68
- by SQUID magnetometry in a field parallel to the film in the normal state at T > Tc. A significant hysteresis of M(H) reveals the in-plane anisotropy of Co films (albeit with a small coercive field, HC ≈ 30 Oe), consistent with earlier studies [44][45][46][47]. Figure 1c shows a numerical simulation
Influence of the magnetic nanoparticle coating on the magnetic relaxation time
Beilstein J. Nanotechnol. 2020, 11, 1207–1216, doi:10.3762/bjnano.11.105
- fill in this gap, this study presents a numerical simulation model that elucidates how the nanoparticle coating affects the nanoparticle agglomeration tendency as well as the effective magnetic relaxation time of the system. To simulate the self-organization of the colloidal nanoparticles, a stochastic
- relaxation time; nanoparticle coating; numerical simulation; stochastic Langevin dynamics method; superparamagnetic nanoparticles; Introduction One of the most important biomedical applications of colloidal magnetic nanoparticle systems is magnetic hyperthermia applied as an alternative for cancer treatment
- corresponding magnetic configuration of the system. For the numerical simulation, two widely known models have been used [19][20][21]. We started with a system of single-domain magnetic nanoparticles, consisting of spherical iron-oxide nanoparticles with uniaxial magnetic anisotropy, which have a lognormal
Thermophoretic tweezers for single nanoparticle manipulation
Beilstein J. Nanotechnol. 2020, 11, 1126–1133, doi:10.3762/bjnano.11.97
- , and the feedback loop frequency. The numerical simulation reproduced the experimental findings very well and can be thus utilized for the estimation of the stiffness for any combination of parameters. The all-optical creation of the tweezers allows for their dynamic relocation. Consequently, it
Current measurements in the intermittent-contact mode of atomic force microscopy using the Fourier method: a feasibility analysis
Beilstein J. Nanotechnol. 2020, 11, 453–465, doi:10.3762/bjnano.11.37
- second case, we performed a numerical simulation for a dynamic AFM experiment that operates in the attractive tip–sample interaction regime. For this we have integrated the equation of motion of a spring–mass–dashpot model (Equation 21), customarily used to model dynamic AFM [45], where meff is the
- spectrum of the cantilever response (Figure 6), one can observe that the an values decrease rather rapidly, such that only the first peak contributes significantly. Therefore, the frequency representation of the tunnelling current obtained for the numerical simulation is very close to the representation
- numerical simulation for case 3 is similar to that of case 2, except that only repulsive forces are considered, which are based on the Hertzian contact model (for simplicity, the attractive forces are not included). The simulation parameters can be found in Table 2. Here we first consider (i) an unperturbed
Understanding nanoparticle flow with a new in vitro experimental and computational approach using hydrogel channels
Beilstein J. Nanotechnol. 2020, 11, 296–309, doi:10.3762/bjnano.11.22
- results are grid independent. The computed mass losses of the particles are 1.341% and 6.253% for 4.12 g and 2.008 g inlet concentrations of NP fluid flow in hydrogel channels, respectively. It is observed that the numerical simulation results favorably agree with experimental data (1.286% and 5.96
An investigation on the drag reduction performance of bioinspired pipeline surfaces with transverse microgrooves
Beilstein J. Nanotechnol. 2020, 11, 24–40, doi:10.3762/bjnano.11.3
- Chemical and Petroleum Engineering, University of Calgary, Calgary T2N1N4, Canada 10.3762/bjnano.11.3 Abstract A novel surface morphology for pipelines using transverse microgrooves was proposed in order to reduce the pressure loss of fluid transport. Numerical simulation and experimental research efforts
- obtained by an orthogonal analysis method. The comparative experiments were conducted in a water tunnel, and a maximum drag reduction rate of 3.21% could be achieved. The numerical simulation and experimental results were cross-checked and found to be consistent with each other, allowing to verify that the
- wall), which reduced the influence of wall grid density on computational accuracy. This is why the SST κ–ω model has been widely used to solve the turbulent flow field. Considering the computational accuracy and cost, the Reynolds-averaged Navier–Stokes (RANS) numerical simulation method with the SST
Mobility of charge carriers in self-assembled monolayers
Beilstein J. Nanotechnol. 2019, 10, 2449–2458, doi:10.3762/bjnano.10.235
- Figure 1). This expression is not strictly correct, but numerical simulation reveals a deviation of less than 1% [29]. In the following we assume a 1D transport of charges along the (112) direction, because from the packing of the PAT-molecules (see Figure 3 and Figure 1g), we expect good π–π-overlap
Dynamics of superparamagnetic nanoparticles in viscous liquids in rotating magnetic fields
Beilstein J. Nanotechnol. 2019, 10, 2294–2303, doi:10.3762/bjnano.10.221
- SAR values of the order of 400–500 W/g can be obtained in a rotating magnetic field with a frequency f = 400 kHz and a moderate magnetic field amplitude H0 = 100 Oe. Keywords: magnetic hyperthermia; magnetic nanoparticles; numerical simulation; rotating magnetic field; specific absorption rate
- magnetic hyperthermia. As Figure 7b shows, in this case SAR values of about 400–600 W/g can be obtained over a wide range of nanoparticle diameters, D = 20–30 nm. Conclusion In this paper the dynamics of superparamagnetic nanoparticles in a viscous fluid in RMFs is studied using both numerical simulation
- in magneto-dynamics (MD) approximation are shown in slide 2. Numerical simulation results for the dynamics of vectors α and n in different modes are given in slides 3–5. The dynamics of vectors α and n for modes 1, 2, and 3 are shown in slides 3, 4, and 5, respectively. Supporting Information File
Heating ability of magnetic nanoparticles with cubic and combined anisotropy
Beilstein J. Nanotechnol. 2019, 10, 305–314, doi:10.3762/bjnano.10.29
- . However, the ability of magnetic nanoparticle assemblies to generate heat can be improved if the nanoparticles are covered by nonmagnetic shells of appreciable thickness. Keywords: fractal clusters; magnetite nanoparticles; magneto–dipole interaction; numerical simulation; specific absorption rate
- = 50–100 Oe, at a typical frequency f = 300 kHz. This shows the substantial potential of these nanoparticles for application in magnetic nanoparticle hyperthermia. Numerical Simulation It has been recently shown [22] that the technique based on the stochastic LL equation is preferable for investigation
- magnetite nanoparticles with diameter D ≥ D0. The results of the numerical simulation shown in Figure 2 and Figure 3 correspond to spherical magnetite nanoparticles. They are also qualitatively true for perfect magnetite nanoparticles of cubic external shape [8][10] having cubic magnetic anisotropy
Performance analysis of rigorous coupled-wave analysis and its integration in a coupled modeling approach for optical simulation of complete heterojunction silicon solar cells
Beilstein J. Nanotechnol. 2018, 9, 2315–2329, doi:10.3762/bjnano.9.216
- solar cells, reliable and accurate optical models implemented in numerical simulation tools are of great importance [10]. The models that enable simulations of thick incoherent and thin coherent layers, including textures of nano-, micro- and several micro-(macro) meter size, are required. Different
Numerical analysis of single-point spectroscopy curves used in photo-carrier dynamics measurements by Kelvin probe force microscopy under frequency-modulated excitation
Beilstein J. Nanotechnol. 2018, 9, 1834–1843, doi:10.3762/bjnano.9.175
- given to the mathematical model used in the data-fitting process as it constitutes a determining aspect in the calculation of time constants. Here, we propose and demonstrate an automatic numerical simulation routine that enables to predict the behavior of spectroscopy curves of the average surface
- work, where the minority-carrier lifetime in a silicon nanocrystal solar cell was obtained by KPFM spectroscopy under frequency-modulated light illumination [3]. This can be done by fixing the SPV decay time in the numerical simulation to the value predicted by the mathematical fit used on that
- occasion and comparing the correspondence between the spectroscopy curve resulting from the mathematical fit and the data points obtained from the numerical simulation. In [3], minority-carrier lifetime values were calculated through a mathematical fit procedure derived from previous publications [5] using
Mechanistic insights into plasmonic photocatalysts in utilizing visible light
Beilstein J. Nanotechnol. 2018, 9, 628–648, doi:10.3762/bjnano.9.59
- parameters of plasmonic metal nanostructures such as particle size, work function, surface facet and plasmonic band is a challenging task that demands numerical simulation. It is known that the photocatalysis performance is affected by the noble metal particle size and thus finite difference time domain
Revealing the interference effect of Majorana fermions in a topological Josephson junction
Beilstein J. Nanotechnol. 2018, 9, 520–529, doi:10.3762/bjnano.9.50
- trivial fermion states interfere with each other, the situation is very different. Though an analytic result cannot be obtained, our numerical simulation suggest that the general formula for the DOS for the electron (hole) part should be , with a and b being real constants. This can be understood as
Numerical investigation of the tribological performance of micro-dimple textured surfaces under hydrodynamic lubrication
Beilstein J. Nanotechnol. 2017, 8, 2324–2338, doi:10.3762/bjnano.8.232
- hydrodynamic lubrication. Due to the complexity of the governing equations, however, it is difficult to obtain an analytical solution. Therefore, a numerical simulation is adopted in this study to solve the problem. Characterization of tribological properties The effect of the micro-dimple array on the
- . Numerical simulation Meshing The three-dimensional model of the computational domain was meshed by using GAMBIT software. In order to obtain a high-quality mesh, the model was divided into three domains (see Figure 3). The micro-dimple was located in domain two and domain three. In order to guarantee the
- are required to fill the horizontal extent of the dimple. Since the mesh size has a great effect on the accuracy and efficiency of the numerical simulation, the grid independence analysis was carried out to develop the proper meshing strategy. The variation of the mesh size may affect the film
Molecular dynamics simulations of nanoindentation and scratch in Cu grain boundaries
Beilstein J. Nanotechnol. 2017, 8, 2283–2295, doi:10.3762/bjnano.8.228
- of the material along with the complex dislocation phenomenon of the grain boundary is unclear at the macroscopic scale. In the past few years, many researchers have used numerical simulation analysis to discuss the mechanical properties of metals [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17
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