Heating ability of elongated magnetic nanoparticles

• Elizaveta M. Gubanova,
• Nikolai A. Usov and
• Vladimir A. Oleinikov

Beilstein J. Nanotechnol. 2021, 12, 1404–1412, doi:10.3762/bjnano.12.104

• anisotropy constant, Kef ≈ KSh, determines the characteristic value of the reduced energy barrier between potential wells. The latter is equal in order of magnitude to σ = KefV/kBT, where kB is the Boltzmann constant and T is the absolute temperature. The dynamics of the unit magnetization vector of a

• field, is very small. At the same time, at small values of this parameter, σ ≪ 1, the dynamics of the unit magnetization vector is determined by thermal fluctuations, and the effect of the ac magnetic field is insignificant. Therefore, at fixed amplitude of the ac magnetic field, with increase in the

Cantilever signature of tip detachment during contact resonance AFM

• Devin Kalafut,
• Ryan Wagner,
• Maria Jose Cadena,
• Anil Bajaj and
• Arvind Raman

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

• Leonid S. Revin,
• Dmitriy V. Masterov,
• Alexey E. Parafin,
• Sergey A. Pavlov and
• Andrey L. Pankratov

Beilstein J. Nanotechnol. 2021, 12, 1279–1285, doi:10.3762/bjnano.12.95

• ; Shapiro steps; temperature dependence; YBaCuO Josephson junction; Introduction High-temperature superconducting (HTSC) Josephson junctions (JJs) are of great interest since many physical properties can be observed in dynamics during the changing the temperature within a wide range from nitrogen

• increases, and for 20 K, in the general case, Equation 1 becomes invalid, that is, the dynamics of the spatial distribution of the phase and the magnetic field inside the junction becomes important [39][40][41]. In the case of long JJs it is necessary to consider the sine-Gordon equation, taking into

• account the non-uniform distribution of currents flowing through the barrier, which is typical for bicrystal junctions [28][42][43]. However, if the junction length is of the order of the kink size and there is no external magnetic field, the long junction dynamics is close to that of a short one [39] and

A review on slip boundary conditions at the nanoscale: recent development and applications

• Ruifei Wang,
• Jin Chai,
• Bobo Luo,
• Xiong Liu,
• Jianting Zhang,
• Min Wu,
• Mingdan Wei and
• Zhuanyue Ma

Beilstein J. Nanotechnol. 2021, 12, 1237–1251, doi:10.3762/bjnano.12.91

• 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

• Beskok compared a slip-modified theoretical model with the molecular dynamics simulation results. They found that the slip enhancement in the electro-osmotic flow is independent of the channel height, which can provide a theoretical basis for membrane fabrication of electrically assisted nanofiltration

Impact of electron–phonon coupling on electron transport through T-shaped arrangements of quantum dots in the Kondo regime

• Patryk Florków and
• Stanisław Lipiński

Beilstein J. Nanotechnol. 2021, 12, 1209–1225, doi:10.3762/bjnano.12.89

• Nph is given by the Bose–Einstein distribution. In this approach the electron and phonon dynamics become decoupled. This approximation, which is widely used in literature [49][58][59][70][71][72], predicts the exponential suppression of the tunneling amplitudes (Franck–Condon (F–C)-type suppression

• state and double or fourfold occupied states become degenerate. The low-temperature dynamics is then described only by charge fluctuations, that is, flips of charge pseudospin (charge Kondo effect). Of special interest are the effective fluctuations between degenerate empty and fully occupied states

Irradiation-driven molecular dynamics simulation of the FEBID process for Pt(PF₃)₄

• Alexey Prosvetov,
• Alexey V. Verkhovtsev,
• Gennady Sushko and
• Andrey V. Solov’yov

Beilstein J. Nanotechnol. 2021, 12, 1151–1172, doi:10.3762/bjnano.12.86

• presents a detailed computational protocol for the atomistic simulation of formation and growth of metal-containing nanostructures during focused electron beam-induced deposition (FEBID). The protocol is based upon irradiation-driven molecular dynamics (IDMD), a novel and general methodology for computer

• deposition; irradiation-driven molecular dynamics; irradiation-induced chemistry; platinum nanostructures; reactive force fields; Introduction The controllable fabrication of nanostructures with nanoscale resolution remains a considerable scientific and technological challenge [1]. To address this challenge

• dynamics (IDMD) [13], a novel and general methodology for computer simulations of irradiation-driven transformations of complex molecular systems. This approach overcomes the limitations of previously used computational methods and describes FEBID-based nanostructures at the atomistic level by accounting

Self-assembly of amino acids toward functional biomaterials

• Huan Ren,
• Lifang Wu,
• Lina Tan,
• Yanni Bao,
• Yuchen Ma,
• Yong Jin and
• Qianli Zou

Beilstein J. Nanotechnol. 2021, 12, 1140–1150, doi:10.3762/bjnano.12.85

• ]. Although traditional materials provide good structural analogues for native bone and surrounding tissue, they are difficult to mimic the dynamics and complexity of the natural environment [9]. Therefore, it is necessary to develop a new generation of biomaterials to improve strategies for natural tissue

• phenylketonuria. Bera et al. [37] studied the effect of chiral on aromatic amino acid self-assembly. They found that the hybrid ᴅʟ system (racemate) alters the morphology and dynamics of the assemblies. For example, either ʟ-phenylalanine or ᴅ-phenylalanine can form amyloid fibers, but the ᴅʟ system shows a

Open-loop amplitude-modulation Kelvin probe force microscopy operated in single-pass PeakForce tapping mode

• Gheorghe Stan and
• Pradeep Namboodiri

Beilstein J. Nanotechnol. 2021, 12, 1115–1126, doi:10.3762/bjnano.12.83

• microscopy [29][30], pump–probe KPFM [31][32], or fast free force recovery KPFM [33] that are capable of observing the dynamics of the optoelectronic response of materials and electric field-induced charge migration at time scales of the order of tens of microseconds. Various OL KPFM implementations with

• scale of the order of 20 μs, which is about one hundred times faster than CL KPFM modes and could be used to observe ultrafast dynamics of electrical processes [35][46]. Due to the long-range nature of the electrostatic interactions, contributions from all the conductive parts (apex, cone, and

An overview of microneedle applications, materials, and fabrication methods

• Zahra Faraji Rad,
• Philip D. Prewett and
• Graham J. Davies

Beilstein J. Nanotechnol. 2021, 12, 1034–1046, doi:10.3762/bjnano.12.77

• in a study which integrated hollow silicon microneedles with a reservoir unit, a piezoelectric actuator system, and a flow sensor for real-time measurements of fluid dynamics [46]. In other research, much smaller microneedles – just 8 μm in height and 1 μm in diameter – were fabricated by DRIE for

The role of convolutional neural networks in scanning probe microscopy: a review

• Ido Azuri,
• Irit Rosenhek-Goldian,
• Neta Regev-Rudzki,
• Georg Fantner and
• Sidney R. Cohen

Beilstein J. Nanotechnol. 2021, 12, 878–901, doi:10.3762/bjnano.12.66

• review highlights the efficiency of various CNNs for noise removal compared to conventional de-noising [132]. Extracting quantitative information about the dynamics occurring in the sample from fully processed HS-AFM images is a time-consuming task, since one experiment can consist of tens of thousands

Effects of temperature and repeat layer spacing on mechanical properties of graphene/polycrystalline copper nanolaminated composites under shear loading

• Chia-Wei Huang,
• Man-Ping Chang and
• Te-Hua Fang

Beilstein J. Nanotechnol. 2021, 12, 863–877, doi:10.3762/bjnano.12.65

• ) composites under shear loading are investigated by molecular dynamics simulations. The effects of different temperatures, graphene chirality, repeat layer spacing, and grain size on the mechanical properties, such as failure mechanism, dislocation, and shear modulus, are observed. The results indicate that

• . Keywords: dislocation; graphene/Cu; molecular dynamics; shear; self-healing; Introduction Graphene is a monolayered hexagonal thin film composed of sp2-bonded carbon atoms and has extraordinary properties for applications in nanoelectronics [1][2][3][4][5][6]. However, because of the two-dimensional

• this work, we focus on temperature and microstructure effects on graphene/polycrystalline copper nanolaminated (GPCuNL) composites. As mentioned above, the microstructure plays a crucial role for the mechanical behavior of GPCuNL composites. Thus, in the present study, molecular dynamics (MD

Comprehensive review on ultrasound-responsive theranostic nanomaterials: mechanisms, structures and medical applications

• Sepand Tehrani Fateh,
• Lida Moradi,
• Elmira Kohan,
• Michael R. Hamblin and
• Amin Shiralizadeh Dezfuli

Beilstein J. Nanotechnol. 2021, 12, 808–862, doi:10.3762/bjnano.12.64

• anticancer drugs [139]. They can also be targeted to specific tissues through surface modification with different ligands [169][170]. Azmin et al. reviewed MB dynamics and the physical principles behind MBs, providing a theoretical basis for the development of MB-based theranostic systems [171]. Some

Reducing molecular simulation time for AFM images based on super-resolution methods

• Zhipeng Dou,
• Jianqiang Qian,
• Yingzi Li,
• Rui Lin,
• Jianhai Wang,
• Peng Cheng and
• Zeyu Xu

Beilstein J. Nanotechnol. 2021, 12, 775–785, doi:10.3762/bjnano.12.61

• can be used to speed up the generation of training data and vary simulation resolution for AFM machine learning. Keywords: atomic force microscopy; Bayesian compressed sensing; convolutional neural network; molecular dynamics simulation; super resolution; Introduction Atomic force microscopy methods

• . The energy maps of the interaction between several tips and samples under different conditions are simulated in dynamic and quasi-static modes. The molecular dynamics simulation details and main steps of reconstruction algorithms are presented. Then, several reconstruction results are conducted to

• dynamics simulation To test the effectiveness of the reconstruction algorithms we perform molecular dynamics simulations of AFM imaging in different conditions. The dynamic process (AM mode) and quasi-static process (the relative position of tip–sample remains unchanged in the simulation) are separately

Recent progress in magnetic applications for micro- and nanorobots

• Ke Xu,
• Shuang Xu and
• Fanan Wei

Beilstein J. Nanotechnol. 2021, 12, 744–755, doi:10.3762/bjnano.12.58

• microenvironment to promote intracellular biocatalysis. MaBiDz dynamics were significantly enhanced compared with free BiDz. MaBiDz also has cytocompatibility, is easy to integrate with cells, and exhibits intracellular stability. These features make it possible to quickly detect breast adenocarcinoma biomarkers

Electromigration-induced formation of percolating adsorbate islands during condensation from the gaseous phase: a computational study

• Alina V. Dvornichenko,
• Vasyl O. Kharchenko and
• Dmitrii O. Kharchenko

Beilstein J. Nanotechnol. 2021, 12, 694–703, doi:10.3762/bjnano.12.55

• dynamics of the evolution of surface morphology at elevated temperatures. This effect can lead to a change in the morphology of the surface compared to the isotropic case of deposition without the presence of an external field. Mathematical and numerical modeling of nanostructured thin film growth

• processes allows one to analyze in detail the dynamics of this process, to establish the influence of basic factors (pressure inside the chamber, deposition temperature, energy characteristics, and external influence) on the morphology of the growing surface and type and size of surface structures. One of

• the formation of nanoscale clusters of point defects in solids exposed to irradiating sources [69][70][71][72][73]. Electromigration effects The main purpose of this work is to study the effect of electromigration on the dynamics of surface growth during deposition, its morphology, and statistical

A review of defect engineering, ion implantation, and nanofabrication using the helium ion microscope

• Frances I. Allen

Beilstein J. Nanotechnol. 2021, 12, 633–664, doi:10.3762/bjnano.12.52

Surface-enhanced Raman scattering of water in aqueous dispersions of silver nanoparticles

• Paulina Filipczak,
• Krzysztof Hałagan,
• Jacek Ulański and
• Marcin Kozanecki

Beilstein J. Nanotechnol. 2021, 12, 497–506, doi:10.3762/bjnano.12.40

• near gold nanoparticles protected by various ligands [38][39]. The results of hydrogen bond dynamics and calculated far-IR spectra showed that a well-defined multilayered structure of water is formed close to the surface of the metal nanoparticle. The stabilization of this structure may be additionally

• are faster than molecular dynamics methods. The simulations were performed on a 100×100×32 FCC lattice and averaged over 10 000 time units. Two stiff immobile walls representing Ag {100} surfaces were placed at z = 1 and z = 32. In other directions, (x, y) periodic boundary conditions were used. All

Spontaneous shape transition of Mn_xGe_1−x islands to long nanowires

• S. Javad Rezvani,
• Luc Favre,
• Gabriele Giuli,
• Yiming Wubulikasimu,
• Isabelle Berbezier,
• Augusto Marcelli,
• Luca Boarino and
• Nicola Pinto

Beilstein J. Nanotechnol. 2021, 12, 366–374, doi:10.3762/bjnano.12.30

• using these techniques, NWs are grown away from the substrate, usually in a tilted direction, and size distribution and geometry strongly depend on the growth dynamics [32][33]. Furthermore, it is known that the catalyst introduces uncontrolled and unwanted contamination inside the crystal lattice of

Intracranial recording in patients with aphasia using nanomaterial-based flexible electronics: promises and challenges

• Qingchun Wang and
• Wai Ting Siok

Beilstein J. Nanotechnol. 2021, 12, 330–342, doi:10.3762/bjnano.12.27

• has an excellent temporal resolution at the millisecond scale. ECoG data have a typical sampling rate of 1,000–3,000 Hz. This high temporal resolution offers an opportunity to observe the rapid dynamics of neural activities in precisely localized brain regions. ECoG has a much higher signal-to-noise

• , iEEG is a promising method to reveal the dynamics of natural semantic processing. Khachatryan et al. [64] recorded neural signals from the scalp and cortex of nine epileptic subjects to study the activation of semantic and perceptual priming (Figure 4). Patients completed a semantic judgment task and

Differences in surface chemistry of iron oxide nanoparticles result in different routes of internalization

• Barbora Svitkova,
• Vlasta Zavisova,
• Veronika Nemethova,
• Martina Koneracka,
• Miroslava Kretova,
• Filip Razga,
• Monika Ursinyova and
• Alena Gabelova

Beilstein J. Nanotechnol. 2021, 12, 270–281, doi:10.3762/bjnano.12.22

• or cytoskeleton dynamics was quantified by atomic absorption spectroscopy (AAS) and the uptake was verified by fluorescent microscopy. The uptake route of the tested MNPs differed depending on the surface coating. While BSA-SO-MNPs were internalized via CME, PEG-SO-MNPs were preferentially taken up

• experiments, cells were exposed to MNPs in a medium supplemented with 2% FBS. A549 cells up to 20 generations (passaged two times per week) were used in the experiments. Treatment of cells After reaching exponential growth, cells were pre-treated with inhibitors of endocytosis or cytoskeleton dynamics for 1 h

• additional time of 1 h. Cell exposure was finished by sucking off the culture medium and washing the cells twice with phosphate-buffered saline (PBS). An illustration of the treatment is shown in Figure 4. The final concentrations of individual inhibitors of endocytosis or cytoskeleton dynamics were prepared

The nanomorphology of cell surfaces of adhered osteoblasts

• Christian Voelkner,
• Mirco Wendt,
• Regina Lange,
• Max Ulbrich,
• Martina Gruening,
• Susanne Staehlke,
• Barbara Nebe,
• Ingo Barke and
• Sylvia Speller

Beilstein J. Nanotechnol. 2021, 12, 242–256, doi:10.3762/bjnano.12.20

• capability of apical membrane features and fluctuation dynamics in aiding the assessment of adhesion and migration properties on a single-cell basis. Keywords: cell adhesion; membrane fluctuations; osteoblast; plasma membrane nanomorphology; scanning ion conductance microscopy (SICM); Introduction

• of 0.3–0.5 features per μm2, are observed. The characteristic dynamics of the sheets is fast compared to the acquisition leading to temporal undersampling. This results in distortions, which is particularly evident in Figure 2e where the ruffles appear as blurred bright spots. This becomes obvious

• when the live-cell dynamics is suppressed upon fixation of the osteoblasts with 4% paraformaldehyde (PFA). Figure 3a shows an example of a respective SICM topography. Now, the ruffles exhibit a clearer shape and resemble similar features to those observed with electron microscopy [29][30]. Our data

The role of gold atom concentration in the formation of Cu–Au nanoparticles from the gas phase

• Yuri Ya. Gafner,
• Svetlana L. Gafner,
• Darya A. Ryzkova and
• Andrey V. Nomoev

Beilstein J. Nanotechnol. 2021, 12, 72–81, doi:10.3762/bjnano.12.6

• composition; however, the size of the resulting particles varies significantly. To solve this issue, we studied the formation of Cu–Au nanoparticles with different chemical compositions from a gaseous medium using computer molecular dynamics (MD) simulation. The aim was to determine the effect of the

• initial vapor phase, basically corresponded to a given target composition. Keywords: binary nanoparticles; computer simulation; copper; gold; molecular dynamics; Introduction The nanometer-sized Cu–Au compounds are being studied quite actively [1][2][3][4][5][6][7][8] because of their potential

• dynamics (MD) method, which allows us to analyze the behavior of the simulated system over a wide time interval (from picoseconds to several nanoseconds) and with the accuracy required to consider small atomic groups. This type of modeling can only be successful if a sufficiently realistic potential of

Effect of different silica coatings on the toxicity of upconversion nanoparticles on RAW 264.7 macrophage cells

• Cynthia Kembuan,
• Helena Oliveira and
• Christina Graf

Beilstein J. Nanotechnol. 2021, 12, 35–48, doi:10.3762/bjnano.12.3

• -coated UCNPs on RAW 264.7 macrophages, an analysis of the cell cycle dynamics of UCNP@thin_NH2 and UCNP@thick_NH2 samples was carried out. The cell cycle consists of four parts: The rest phase (G0); the first gap phase (G1), in which the cells grow and produce enzymes necessary for cell division; the

• @thin_NH2 sample and 0.35 ± 0.14 for the UCNP@thick_NH2 sample) compared to the control (0.53 ± 0.06). In contrast to this observation, the silica particles without a UCNP core (sample NP@SiO2-RBITC-NH2) exhibit similar cell-cycle dynamics as the nanoparticle-free control (Figure S4, Supporting Information

• the control is marked by a yellow-framed peak. (B) Summary of mean SSC flow cytometry measurements on all samples in RAW 264.7 cells after particle exposure for 24 h at 37 °C. Effect of (A) UC@thin_NH2 (tSiO2 = 8 ± 2 nm) and (B) UC@thick_NH2 (tSiO2 = 21 ± 2 nm) on the cell cycle dynamics of RAW 264.7

Scanning transmission imaging in the helium ion microscope using a microchannel plate with a delay line detector

• Eduardo Serralta,
• Nico Klingner,
• Olivier De Castro,
• Michael Mousley,
• Santhana Eswara,
• Serge Duarte Pinto,
• Tom Wirtz and
• Gregor Hlawacek

Beilstein J. Nanotechnol. 2020, 11, 1854–1864, doi:10.3762/bjnano.11.167

• channeling effect in the HIM has also been studied using Monte Carlo [21] and molecular dynamics [22] simulations. Measuring the energy of the transmitted particles is a novel technique that adds an information channel to the previously discussed transmission imaging modes. It will provide information on the

Nanomechanics of few-layer materials: do individual layers slide upon folding?

• Ronaldo J. C. Batista,
• Rafael F. Dias,
• Ana P. M. Barboza,
• Alan B. de Oliveira,
• Taise M. Manhabosco,
• Thiago R. Gomes-Silva,
• Matheus J. S. Matos,
• Andreij C. Gadelha,
• Cassiano Rabelo,
• Luiz G. L. Cançado,
• Ado Jorio,
• Hélio Chacham and
• Bernardo R. A. Neves

Beilstein J. Nanotechnol. 2020, 11, 1801–1808, doi:10.3762/bjnano.11.162

• methods; atomic force microscopy (AFM); molecular dynamics (MD); Raman spectroscopy; nanostructured materials; Introduction Layered materials such as graphite, talc, and transition metal dichalcogenides (TMDs), held together by strong covalent bonds within layers and relatively weak van der Waals

• been obtained through radial deformations [32], lattice dynamics studies [33], deformations of suspended layers [2][6], and bubble profiles [12]. The values reported for the bending stiffness of a graphene monolayer vary from 0.8 to 10,000 eV [34]. Also, there is no consensus on how κ varies with the

• folded 2D material. In principle, the model describes any 2D material, and its predictions are corroborated by comparison with classical molecular dynamics simulations and to results of previous investigations on graphene and talc. Because folds naturally occur in flakes of varying thickness