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Search for "simulations" in Full Text gives 536 result(s) in Beilstein Journal of Nanotechnology. Showing first 200.
Micro-structures, nanomechanical properties and flight performance of three beetles with different folding ratios
Beilstein J. Nanotechnol. 2022, 13, 845–856, doi:10.3762/bjnano.13.75
- through wind tunnel tests and numerical simulations, it was found that a higher aspect ratio of bionic wings leads to a higher lift-to-drag ratio [19]. The three-dimensional effect of flow is weakened with increasing aspect ratio, which increases the aerodynamic coefficient [47]. Based on beetle hind wing
Gelatin nanoparticles with tunable mechanical properties: effect of crosslinking time and loading
Beilstein J. Nanotechnol. 2022, 13, 778–787, doi:10.3762/bjnano.13.68
- stiffer particles is explained by a lower energy needed to engulf them as demonstrated by coarse grain simulations [6]. The simulations showed a faster receptor binding for more deformable particles due to the larger surface area upon deformation. However, when it comes to membrane wrapping and
Recent advances in nanoarchitectures of monocrystalline coordination polymers through confined assembly
Beilstein J. Nanotechnol. 2022, 13, 763–777, doi:10.3762/bjnano.13.67
- building blocks of coordination polymers [94]. Ex situ and in situ characterizations and computer simulations have been employed to investigate and analyze the crystallization processes of several coordination polymers [94][95][96][97]. The results suggest that there are many kinds of prenucleation
A superconducting adiabatic neuron in a quantum regime
Beilstein J. Nanotechnol. 2022, 13, 653–665, doi:10.3762/bjnano.13.57
- and the formation of the sigmoidal activation function have also been studied. We start with the parameters of the input flux as presented in Figure 3. Numerical simulations demonstrate a distortion of the sigmoidal form of the activation function even when the SQ neuron is initialized in the ground
- instantaneous eigenbasis. Numerical simulations are performed for the temperature of the bosonic thermostat at T = 50 mK. We investigated the relaxation of the excited states for both the single-well (l < l*, Figure 10a,c) and double-well (l > l*, Figure 10b,d) potential shapes. The key result is the
- SQ neuron concept was developed with the support of the Russian Science Foundation (project no. 20-12-00130). The numerical simulations were supported by UNN within the framework of the strategic academic leadership program “Priority 2030” of the Ministry of Science and Higher Education of the
Fabrication and testing of polymer microneedles for transdermal drug delivery
Beilstein J. Nanotechnol. 2022, 13, 629–640, doi:10.3762/bjnano.13.55
- the MN before skin rupture. Several methods are used to estimate these critical loads and their associated stresses, including theoretical analysis, experimental investigations, and FEA simulations [21]. For example, due to the skin’s SC barrier, the normal (vertical) insertion of MN patches on the
Comparative molecular dynamics simulations of thermal conductivities of aqueous and hydrocarbon nanofluids
Beilstein J. Nanotechnol. 2022, 13, 620–628, doi:10.3762/bjnano.13.54
- nanoparticles can enhance the properties of both polar and nonpolar fluids. In the current paper, dispersions of nanoparticles were carried out in hydrocarbon and aqueous-based fluids using molecular dynamic simulations (MDS). The MDS results have been validated using the autocorrelation function and previous
- well. Moreover, except for Abid et al. [31], there are not many studies which discuss polar and nonpolar fluid thermal conductivities. However, experimental studies rather than simulations have been carried out. In their study they have not used alkanes; rather, they have used kerosene oil as a
- atomic level. Although a lot of research has been dedicated to different molecular dynamics simulations of phase transitions and thermal properties of nanofluids, unlike previous works, this research aims to examine the thermal behaviour of water/CuO and alkane/CuO nanofluids by comparing the behaviour
Approaching microwave photon sensitivity with Al Josephson junctions
Beilstein J. Nanotechnol. 2022, 13, 582–589, doi:10.3762/bjnano.13.50
- achieve in real junctions. In our opinion, the most reliable way to determine the critical current is to compare the experimental lifetime as a function of the current with the lifetime calculated using numerical simulations [39][40][41] in the frame of the resistively–capacitively shunted junction (RCSJ
- need to use numerical simulations since, in the experiment, we are limited by the time constant of the filters that provide suppression of external interferences. As a result, we cannot measure switching times faster than the time constant, which in our case is about 1 ms. To obtain shorter times, we
- increases significantly. In Figure 5, one can see how the switching probability evolves with increasing temperature from 50 to 500 mK. The difference is not very large because at 50 mK the effective temperature was rather 265 mK, according to numerical simulations, and the thermal current at 500 mK is much
Zinc oxide nanostructures for fluorescence and Raman signal enhancement: a review
Beilstein J. Nanotechnol. 2022, 13, 472–490, doi:10.3762/bjnano.13.40
- Previous simulations have shown that the Ag NPs exhibit the greatest plasmonic activity in the excitation wavelength range of 400–520 nm and the greatest absorption and electric field energy enhancement at the size of 50–60 nm, while for AuNPs these ranges are 525–580 and 90–100 nm (and potentially bigger
Investigation of electron-induced cross-linking of self-assembled monolayers by scanning tunneling microscopy
Beilstein J. Nanotechnol. 2022, 13, 462–471, doi:10.3762/bjnano.13.39
- simulations, we propose that these voids may correspond to free volumes inside a cross-linked monolayer. Keywords: carbon nanomembranes; electron-induced cross-linking; scanning tunneling microscopy; self-assembled monolayers; subnanometer pores; Introduction Electron-induced chemistry plays an essential
- simulations. Figure 5d shows a typical structure of a TPT CNM, where pronounced valleys and hills in both height and lateral distance from each other can be clearly seen. In a simulation box containing 20 × 20 × 18 carbon atoms, the TPT CNM exhibits three subnanometer pores, corresponding to an areal density
- were analyzed by using an empirical fit. The lateral distribution of subnanometer voids was analyzed by partitioning the surface area into small segments and counting the number of voids in each segment. Classical molecular dynamics simulations The formation of a CNM was modelled using classical
Tunable superconducting neurons for networks based on radial basis functions
Beilstein J. Nanotechnol. 2022, 13, 444–454, doi:10.3762/bjnano.13.37
- implementation of the key elements of the discussed neural networks is the focus of this work. Results and Discussion Model of tunable Gauss-neuron: numerical simulations A common architecture of the considered RBFNs [49] is presented in Figure 1a. These networks have only one hidden layer of neurons on which
- dash–dot line) mutual orientations of magnetization between FM1 and FM2 layers as functions of the spacer thickness. Funding G-neuron and tunable inductance were developed with the support of the Russian Science Foundation (project no. 20-69-47013). The numerical simulations were supported within the
Controllable two- and three-state magnetization switching in single-layer epitaxial Pd1−xFex films and an epitaxial Pd0.92Fe0.08/Ag/Pd0.96Fe0.04 heterostructure
Beilstein J. Nanotechnol. 2022, 13, 334–343, doi:10.3762/bjnano.13.28
- be written in terms of the cubic anisotropy with small tetragonal distortion. In addition, based on the guess simulations, an importance of the uniaxial anisotropy in the film plane became obvious: where αi are directional cosines for the magnetic М with respect to crystallographic axes [100], [010
Theoretical understanding of electronic and mechanical properties of 1T′ transition metal dichalcogenide crystals
Beilstein J. Nanotechnol. 2022, 13, 160–171, doi:10.3762/bjnano.13.11
- to their composition and structural polytypes. However, experimental measurements of the electronic and mechanical properties of 2D materials face the challenge of synthesizing high-quality pristine crystals. Thus, numerical simulations have become a promising alternative due to the relatively good
Nanoscale friction and wear of a polymer coated with graphene
Beilstein J. Nanotechnol. 2022, 13, 63–73, doi:10.3762/bjnano.13.4
- challenging problem due to the complex viscoelastic properties and structure. Using molecular dynamics simulations, we investigate how a graphene sheet on top of the semicrystalline polymer polyvinyl alcohol affects the friction and wear. Our setup is meant to resemble an AFM experiment with a silicon tip. We
- . [27][28] show that graphene has a strong effect on the structure and dynamics of the polymer chains near the interface. In this work, we aim to develop our understanding of the frictional behavior of a polymer coated with graphene by using molecular dynamics simulations of a single sliding asperity at
- the nanoscale. We show that graphene protects the polymer substrate from wear and identify the mechanism of this protection. We show that crumpling of the graphene has an impact on the friction. In the next section we first describe the simulation setup. Then we move on to discussing our simulations
Effect of lubricants on the rotational transmission between solid-state gears
Beilstein J. Nanotechnol. 2022, 13, 54–62, doi:10.3762/bjnano.13.3
- and wear. However, on the microscopic scale, it is not clear to what extent lubricants are beneficial. Therefore, in this study, we consider two diamond solid-state gears at the nanoscale immersed in different lubricant molecules and perform classical MD simulations to investigate the rotational
- fluid. One obtains several fluid properties such as pressure, velocity, shear stress, density and strain rate. In the case of the gear–oil–gear system, several studies based on the CFD simulation have been reported [11][12][13][14][15][16][17][18]. However, most of the simulations for this type of
- and velocity distribution are not well defined and one has to resort to an atomistic description, for example, via molecular dynamics (MD) simulations. Also, the contact mechanics at the nanoscale is very different from the macroscopic case since specific pair interactions have to be taken into
Sputtering onto liquids: a critical review
Beilstein J. Nanotechnol. 2022, 13, 10–53, doi:10.3762/bjnano.13.2
Heating ability of elongated magnetic nanoparticles
Beilstein J. Nanotechnol. 2021, 12, 1404–1412, doi:10.3762/bjnano.12.104
- anisotropy constant was assumed [28][29] to be promising in magnetic hyperthermia. However, numerical simulations [30] showed that for spherical nanoparticles an increase of the uniaxial anisotropy constant leads to a decrease in SAR and a shift of the optimal particle diameters to smaller dimensions
Design aspects of Bi2Sr2CaCu2O8+δ THz sources: optimization of thermal and radiative properties
Beilstein J. Nanotechnol. 2021, 12, 1392–1403, doi:10.3762/bjnano.12.103
- sources. In this work we analyze thermal and radiative properties of such devices based on mesa structures of a layered high-temperature superconductor Bi2Sr2CaCu2O8+δ. Two types of devices are considered containing either a conventional large single crystal or a whisker. We perform numerical simulations
- needle-like whisker. We present numerical simulations for various geometrical configurations and parameters and make a comparison with experimental data. It is demonstrated that the structure and the geometry of both the superconductor and the electrodes play important roles. Electrodes provide an
- Comsol Multiphysics. Below, we present simulations of thermal and radiative properties calculated using “Heat Transfer” and “RF” modules, respectively. The presented simulations contain several simplifications and, therefore, are not aiming to self-consistently predict the extent of self-heating, ΔT, or
Cantilever signature of tip detachment during contact resonance AFM
Beilstein J. Nanotechnol. 2021, 12, 1286–1296, doi:10.3762/bjnano.12.96
- to improve their measurements. We shed light on this issue by deliberately pushing both our experimental equipment and numerical simulations to the point of tip–sample detachment to explore cantilever dynamics during a useful and observable threshold feature in the measured response. Numerical
- simulations of the analytical model allow for extended insight into cantilever dynamics such as full-length deflection and slope behavior, which can be challenging or unobtainable in a standard equipment configuration. With such tools, we are able to determine the cantilever motion during detachment and
- nonlinear response feature to the onset of tip–sample detachment in our numerical simulations to confirm the conclusions from prior works [26][27][28]. The simulations allow for deeper insight into cantilever dynamics during the interaction between the AFM probe tip and the sample, which in turn allow us to
Nonmonotonous temperature dependence of Shapiro steps in YBCO grain boundary junctions
Beilstein J. Nanotechnol. 2021, 12, 1279–1285, doi:10.3762/bjnano.12.95
- shown in Figure 1. Figure 2 shows the IVCs for temperatures of 70 and 50 K in the absence of a high-frequency signal and in the regime of detecting external 72 or 265 GHz signals. The measurement results are in good agreement with the numerical simulations (the black curves). It should be noted that the
A review on slip boundary conditions at the nanoscale: recent development and applications
Beilstein J. Nanotechnol. 2021, 12, 1237–1251, doi:10.3762/bjnano.12.91
- conversion from 3 to 70% [23]. Generally, the methods to investigate slip boundary conditions for nanoconfined liquids include theoretical analysis, physical experiments, and numerical simulations [8][24][25][26][27][28][29][30][31][32][33][34]. In recent years, machine learning methods have also been
- force [39][40][41][42]. However, compared with experimental methods, numerical simulations, such as the lattice Boltzmann method and molecular dynamics (MD) simulation, are more attractive in many aspects. First, numerical simulations can readily reach the system sizes and timescales of practical
- nanoflows [43]. Additionally, numerical methods can provide a controllable way to change a certain property of liquid or solid walls while other properties remain unchanged [44]. In comparison with physical experiments, numerical simulations allow researchers to study the density, velocity profiles, and
Irradiation-driven molecular dynamics simulation of the FEBID process for Pt(PF3)4
Beilstein J. Nanotechnol. 2021, 12, 1151–1172, doi:10.3762/bjnano.12.86
- simulations of irradiation-driven transformations of complex molecular systems by means of the advanced software packages MBN Explorer and MBN Studio. Atomistic simulations performed following the formulated protocol provide valuable insights into the fundamental mechanisms of electron-induced precursor
- molecule, on a SiO2 surface. The simulations reveal the processes driving the initial phase of nanostructure formation during FEBID, including the nucleation of Pt atoms and the formation of small metal clusters on the surface, followed by their aggregation and the formation of dendritic platinum
- fundamental mechanisms of electron-induced precursor fragmentation and the corresponding mechanisms of nanostructure formation and growth using FEBID. Until recently, most computer simulations of FEBID and nanostructure growth have been performed using a Monte Carlo approach and diffusion–reaction theory [2
Criteria ruling particle agglomeration
Beilstein J. Nanotechnol. 2021, 12, 1093–1100, doi:10.3762/bjnano.12.81
- direction of a minimum of the free enthalpy. In this context, one may observe mechanisms leading to a reduction of the surface energy or controlled by the van der Waals interaction. Additionally, the ensemble may arrange in the direction of a maximum of the entropy. Simulations based on Monte Carlo methods
- teach that, in case of any energetic interaction of the particles, the influence of the entropy is minor or even negligible. Complementary to the simulations, the extremum of the entropy was determined using the Lagrange method. Both approaches yielded identical result for the particle size distribution
- increase at low numbers of collisions to a maximum at Ntot/2, followed by a steep decrease. These relations are depicted in Figure 4 for an ensemble of Ntot = 108 particles. The graphs show a maximum in the vicinity of Ntot/2. Because of the unavoidable fluctuations, simulations cannot determine the exact
A new method for obtaining model-free viscoelastic material properties from atomic force microscopy experiments using discrete integral transform techniques
Beilstein J. Nanotechnol. 2021, 12, 1063–1077, doi:10.3762/bjnano.12.79
- frequency – recall that z = eαeiω), for circles with different radii on the z-plane. The radii of the circles are respectively 1.01, 1.2, 2, and 2.5. As the figures show, the retardance calculated from the simulations and the theoretical values match closely with an error below 0.25%. Notice that the
- compliance, storage compliance and absolute retardance. Material parameters used in the simulations. Supporting Information The Supporting Information features derivations of generalized Voigt and Maxwell–Wiechert models in the Laplace and the z-domains; a brief overview of Fourier, modified Fourier
- , Laplace, and Z-transforms; additional data illustrating the misrepresentation of the system in the Fourier domain and additional data from AFM simulations; and, finally, a detailed analysis of loss and storage as a function of frequency and their estimation from modified Fourier transforms. Supporting
Is the Ne operation of the helium ion microscope suitable for electron backscatter diffraction sample preparation?
Beilstein J. Nanotechnol. 2021, 12, 965–983, doi:10.3762/bjnano.12.73
- interaction volume, a steady-state condition of ion impurity concentration and number of induced defects is reached. The EBSD measurements and Monte Carlo simulations indicate that when this steady-state condition is reached more quickly, which can be achieved using high-energy Ne ions at a glancing incidence
- transmission electron microscopy (STEM), TEM, TEM selected area electron diffraction (SAED), and TEM dark-field (DF) measurements. The results for each experiment are compared to those of a non-irradiated area of the Cu TEM grid. Monte Carlo simulations of the occurring ion–solid interactions are evaluated to
- produce artefacts that would compromise the TEM analysis. Monte Carlo simulations were performed using the program Stopping and Range of Ions in Matter (SRIM) to better understand the underpinning ion–solid interactions for the different settings [22]. The extent of created dislocations, vacancies as well
Molecular assemblies on surfaces: towards physical and electronic decoupling of organic molecules
Beilstein J. Nanotechnol. 2021, 12, 950–956, doi:10.3762/bjnano.12.71
- design often relies on non-planar adsorbates with bulky spacer groups, which can adopt various conformations. From a theoretical point of view, finding the energetically most stable conformational structure can be challenging and costly because conventional atomistic simulations are often limited to the
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