A review of demodulation techniques for multifrequency atomic force microscopy

• David M. Harcombe,
• Michael G. Ruppert and
• Andrew J. Fleming

Beilstein J. Nanotechnol. 2020, 11, 76–91, doi:10.3762/bjnano.11.8

• provide further nanomechanical sample information. These include properties such as sample elasticity, stiffness and adhesiveness [17], which are mapped simultaneously with the topography. Acquiring these observables requires the accurate demodulation of amplitude and phase of multiple frequency

• fundamental resonance frequency of 156.75 kHz. The sample is a blend of polystyrene (PS) and polyolefin elastomer (LDPE) available from Bruker (PS-LDPE-12M). Due to the different elastic moduli of the PS and LPDE regions, the sample is used for evaluating imaging methods that are sensitive to elasticity

Abrupt elastic-to-plastic transition in pentagonal nanowires under bending

• Sergei Vlassov,
• Magnus Mets,
• Boris Polyakov,
• Jianjun Bian,
• Leonid Dorogin and
• Vahur Zadin

Beilstein J. Nanotechnol. 2019, 10, 2468–2476, doi:10.3762/bjnano.10.237

• attributed to the peculiar inner structure of pentagonal NWs. Qin et al. reported on recoverable plasticity in penta-twinned Ag NWs [31] in tensile tests. The enhanced elasticity, exceptional strength and unexpected brittle failure of pentagonal Ag NWs were reported by Zhu et al. [25] in tensile tests and by

• ]. In this model, the pentagonal NW was composed of five triangular prism-shaped domains with vertex angle of 72°. These domains represent the FCC single crystals. Each domain was assigned an elasticity matrix of Ag or Au corresponding to their crystal structure to account for structural anisotropy. The

• elasticity matrix independent parameters in Voigt notation for Ag were C11 = 124 GPa, C12 = 93.4 GPa, C44 = 46.1 GPa and for Au C11 = 190 GPa, C12 = 161 GPa, C44 = 42.3 GPa. The NW was fixed by a portion of the bottom facet at one end and pushed at the other end by applying gradually increasing force. The

Atomic force acoustic microscopy reveals the influence of substrate stiffness and topography on cell behavior

• Yan Liu,
• Li Li,
• Xing Chen,
• Ying Wang,
• Meng-Nan Liu,
• Jin Yan,
• Liang Cao,
• Lu Wang and
• Zuo-Bin Wang

Beilstein J. Nanotechnol. 2019, 10, 2329–2337, doi:10.3762/bjnano.10.223

• are revealed by AFAM. Our results show that AFAM is capable of imaging surface elastic deformations. By immunofluorescence experiments, we find that the L929 cells significantly elongate on the patterned stiffness substrate, whereas the elasticity of the pattern has only little effect on the spreading

• with increasing exposure dose. This could be attributed to the increase of the surface stiffness. To further characterize the elasticity of the substrate the Young’s moduli of the undeveloped arrays were calculated using the Hertzian model. Here, the Young’s modulus measurements were repeated twenty

• spreading of the L929 cells on the patterned stiffness surfaces. This agrees well with the recent finding that changes in the cell shape cannot be attributed to changes of the substrate matrix elasticity [35]. However, the spreading and the differentiation of hepatic stellate cells (HSCs) have been related

Design of a nanostructured mucoadhesive system containing curcumin for buccal application: from physicochemical to biological aspects

• Sabrina Barbosa de Souza Ferreira,
• Gustavo Braga,
• Évelin Lemos Oliveira,
• Jéssica Bassi da Silva,
• Hélen Cássia Rosseto,
• Lidiane Vizioli de Castro Hoshino,
• Mauro Luciano Baesso,
• Wilker Caetano,
• Craig Murdoch,
• Helen Elizabeth Colley and
• Marcos Luciano Bruschi

Beilstein J. Nanotechnol. 2019, 10, 2304–2328, doi:10.3762/bjnano.10.222

• CUR at 25 °C, an increase of G’, G” and η’ and a decrease of tan δ was observed for most frequencies. Hence, these changes provided better structuring and elasticity at 25 °C. However, polymer blends containing CUR investigated at 37 °C displayed lower G’, G” and η’ with an absence of significant

• is also true for saliva, which can also be considered as a natural protection in the organism against impurities exposed to the mucosa and can hinder the retention of such systems and thereby impair the clinical efficacy [65][66][67]. Hardness, compressibility, adhesiveness, elasticity and

• ]. The gel ability to flow and return to the initial state is defined as elasticity [9]. In addition, cohesiveness is related to the restructuration and molecular interactions after subsequent shear stress during the application of the system [67][72]. The incorporation of CUR did not significantly

Precise local control of liquid crystal pretilt on polymer layers by focused ion beam nanopatterning

• Maxim V. Gorkunov,
• Irina V. Kasyanova,
• Vladimir V. Artemov,
• Alena V. Mamonova and
• Serguei P. Palto

Beilstein J. Nanotechnol. 2019, 10, 1691–1697, doi:10.3762/bjnano.10.164

• orientational LC elasticity, which yields the Laplace equation Δθ(r) = 0 for the equilibrium distribution of the LC director [3]. In the homogeneous background area of the LC cell, hybrid LC alignment takes place as the LC is anchored in-plane by rubbed PI at one substrate, θ = π/2 at z = 0, and vertically by

• dependence in Equation 6 used for extracting the pretilt values is strictly applicable only in terms of the one-constant approximation for the LC elasticity. However, it remains sufficiently accurate for realistically different elastic constants. Using values typical for the nematic E7 mixture with the ratio

• striped pattern: The molecules are anchored in-plane along the rubbing direction (white “R” arrow) by pristine PI (light yellow stripes) and orthogonally to the substrate by PI irradiated with FIB (middle darker stripe). The competing aligning actions are averaged by the LC elasticity at some distance

Upcycling of polyurethane waste by mechanochemistry: synthesis of N-doped porous carbon materials for supercapacitor applications

• Christina Schneidermann,
• Pascal Otto,
• Desirée Leistenschneider,
• Sven Grätz,
• Claudia Eßbach and
• Lars Borchardt

Beilstein J. Nanotechnol. 2019, 10, 1618–1627, doi:10.3762/bjnano.10.157

• that accumulate as plastic waste are poorly recyclable because of low recycling yields and insufficient properties of the recycled polymers in terms of elasticity, rheology, and thermal and mechanical stability [5]. Amongst them is PU, a thermosetting polymer with a cross-linked structure [5][11][12

Nanoscale spatial mapping of mechanical properties through dynamic atomic force microscopy

• Zahra Abooalizadeh,
• Leszek Josef Sudak and
• Philip Egberts

Beilstein J. Nanotechnol. 2019, 10, 1332–1347, doi:10.3762/bjnano.10.132

• resonance are avoided) in previous studies, the elastic modulus calculation by FMM requires operation in regions of the spectrum where there is little or no change in amplitude for small frequency shifts. This is to ensure that the amplitude response is restricted to variations of the sample elasticity

• influenced by covered steps of the HOPG surface, out-of-plane elasticity is not. Influence of tip shape As discussed previously, the size and shape of the tip will influence the adhesive interaction between the tip and sample, and thus the total applied normal force. As we have labeled the measurements shown

A Ni(OH)₂ nanopetals network for high-performance supercapacitors synthesized by immersing Ni nanofoam in water

• Donghui Zheng,
• Man Li,
• Yongyan Li,
• Chunling Qin,
• Yichao Wang and
• Zhifeng Wang

Beilstein J. Nanotechnol. 2019, 10, 281–293, doi:10.3762/bjnano.10.27

• layer smoothly adheres to the MG matrix. The thickness of the Ni-NF layer is ca. 1.5 μm; the Ni40Zr20Ti40 MG is ca. 22 μm thick. It is well known that Ni-based MGs exhibit a much larger elasticity and ductility than their corresponding crystalline alloys. A sufficiently thick MG layer acts as a ductile

Pull-off and friction forces of micropatterned elastomers on soft substrates: the effects of pattern length scale and stiffness

• Peter van Assenbergh,
• Marike Fokker,
• Julian Langowski,
• Jan van Esch,
• Marleen Kamperman and
• Dimitra Dodou

Beilstein J. Nanotechnol. 2019, 10, 79–94, doi:10.3762/bjnano.10.8

• is dominated by surface-tension effects, whereas for larger features, surface-tension effects are balanced by elasticity [25]. Summarizing, whereas for rigid substrates, adhesive micropatterns have been designed to gain a low Eeff, it remains to be investigated whether this design approach should

• . Formation of protrusions is a trade-off between, on the one hand, elastic stresses and, on the other hand, the compressive load on the bulk. On the stiffer PVA-18 substrate, this positive effect of a terminal layer on pull-off forces was not observed. PVA-18 has a higher elasticity, likely resulting in a

Recent highlights in nanoscale and mesoscale friction

• Andrea Vanossi,
• Dirk Dietzel,
• Andre Schirmeisen,
• Ernst Meyer,
• Rémy Pawlak,
• Thilo Glatzel,
• Marcin Kisiel,
• Shigeki Kawai and
• Nicola Manini

Beilstein J. Nanotechnol. 2018, 9, 1995–2014, doi:10.3762/bjnano.9.190

• [101] leading to a size-dependent breakdown of structural lubricity. As anticipated, the critical length scale depends sensitively on the ratio between the slider elasticity and the interaction forces with the substrate. Consequently, this transition was experimentally observed only for the MoS2

• and the elasticity of the sliding plates, are needed to account for both laws within the same frictional model. The authors of [201] suggested that insight gained from spring-block frictional models could offer explanations for statistical properties of macroscopic frictional systems, and extended it

A simple extension of the commonly used fitting equation for oscillatory structural forces in case of silica nanoparticle suspensions

• Sebastian Schön and
• Regine von Klitzing

Beilstein J. Nanotechnol. 2018, 9, 1095–1107, doi:10.3762/bjnano.9.101

• interpreted as the distance between the particles within the confinement, is solely dependent on the particle number density and is equal to λ = c−1/3 [35]. This dependence seems fundamental as it is very robust against multiple parameters such as salt concentration, particle size [36], surface elasticity

Scanning speed phenomenon in contact-resonance atomic force microscopy

• Christopher C. Glover,
• Jason P. Killgore and
• Ryan C. Tung

Beilstein J. Nanotechnol. 2018, 9, 945–952, doi:10.3762/bjnano.9.87

• velocity Vs. The adsorbed water layer is surrounding the tip–sample junction but does not exist in the contact region. This case, depicted in Figure 1b, represents a situation where the AFM is solely measuring the elastic properties of the sample. The elasticity of the sample has been represented as the

Effect of microtrichia on the interlocking mechanism in the Asian ladybeetle, Harmonia axyridis (Coleoptera: Coccinellidae)

• Jiyu Sun,
• Chao Liu,
• Bharat Bhushan,
• Wei Wu and
• Jin Tong

Beilstein J. Nanotechnol. 2018, 9, 812–823, doi:10.3762/bjnano.9.75

• abdominal segment extends again, HW2 will not be moved away, and the microtrichia will act as a braking device. The folding results from the structure and elasticity of the cuticles of the veins, which are discontinuous between the proximal and distal parts of the veins in Coleoptera [23]. An investigation

• retains the wing in a fully folded condition. To overcome elasticity these simple transverse folds are usually opened to the extended position and rely on “preening” movements of the abdomen [39]. At this point, the folding is basically completed, and the final state has been achieved. In this state, the

Lyapunov estimation for high-speed demodulation in multifrequency atomic force microscopy

• David M. Harcombe,
• Michael G. Ruppert,
• Michael R. P. Ragazzon and
• Andrew J. Fleming

Beilstein J. Nanotechnol. 2018, 9, 490–498, doi:10.3762/bjnano.9.47

• stiffness, elasticity and adhesiveness [10]. The acquisition of these observables requires tracking the amplitude and phase of additional frequencies of interest. These include higher harmonics of the fundamental frequency [11], higher flexural eigenmodes [12] and intermodulation products [13]. Higher

Engineering of oriented carbon nanotubes in composite materials

• Razieh Beigmoradi,
• Abdolreza Samimi and
• Davod Mohebbi-Kalhori

Beilstein J. Nanotechnol. 2018, 9, 415–435, doi:10.3762/bjnano.9.41

• hard, solid or powder, biological, and organic or inorganic surfaces. This device can measure geometric morphology, adhesion distribution, friction, surface impurities, texture, elasticity, magnetism, chemical bonding forces, distribution of electric charges and electric polarization in different parts

A robust AFM-based method for locally measuring the elasticity of samples

• Alexandre Bubendorf,
• Stefan Walheim,
• Thomas Schimmel and
• Ernst Meyer

Beilstein J. Nanotechnol. 2018, 9, 1–10, doi:10.3762/bjnano.9.1

• Micro Facility (KNMF), Karlsruhe, Germany 10.3762/bjnano.9.1 Abstract Investigation of the local sample elasticity is of high importance in many scientific domains. In 2014, Herruzo et al. published a new method based on frequency-modulation atomic force microscopy to locally determine the elasticity

• elasticity of samples is of high interest in many scientific domains, as many processes and physical quantities are correlated with the elastic modulus. In biology, for instance, studies showed that the elasticity of cells depends on their age, the stage of the cell cycle and the degree of differentiation [1

• ]. In physics, the band gap size of nanocrystals and the presence of planar defects on nanotubes are a function of the Young’s modulus [2][3]. Probing local elasticity requires an instrumentation capable of operating with high resolution and under different conditions, such as variable temperature

Magnetic field induced orientational transitions in liquid crystals doped with carbon nanotubes

• Danil A. Petrov,
• Pavel K. Skokov and
• Alexander N. Zakhlevnykh

Beilstein J. Nanotechnol. 2017, 8, 2807–2817, doi:10.3762/bjnano.8.280

• experimental observations [18][19][23]. Due to induced gradients of the LC director and the increase in the energy of orientationally elastic deformations F1 in Equation 1, the forces of orientational elasticity tend to return the director to the initial planar state. Distortions of the orientational structure

Electro-optical characteristics of a liquid crystal cell with graphene electrodes

• Nune H. Hakobyan,
• Hakob L. Margaryan,
• Valeri K. Abrahamyan,
• Vladimir M. Aroutiounian,
• Arpi S. Dilanchian Gharghani,
• Amalya B. Kostanyan,
• Timothy D. Wilkinson and
• Nelson Tabirian

Beilstein J. Nanotechnol. 2017, 8, 2802–2806, doi:10.3762/bjnano.8.279

• oscillations). Then the relaxation process takes place only under the influence of the molecular forces of elasticity. The system returns to its original oriented state, similar to relaxation after influence of an electric field. The above-mentioned feature of the reorientation process under the influence of

• essentially much larger than in the previous mode due to its dependence on only the rotational viscosity and elasticity of the LC. However, it is possible to achieve higher performance by applying a control voltage with a special shape, which is based on the transition nematic effect (TNE), when a step change

Material discrimination and mixture ratio estimation in nanocomposites via harmonic atomic force microscopy

• Weijie Zhang,
• Yuhang Chen,
• Xicheng Xia and
• Jiaru Chu

Beilstein J. Nanotechnol. 2017, 8, 2771–2780, doi:10.3762/bjnano.8.276

• force, the cantilever oscillation will show certain higher harmonic components [18], which are dominated by contact force and contact time [19][20][21]. Theoretical analysis and preliminary experiments have demonstrated that the harmonic signals are highly sensitive to the variation of local elasticity

• verify that the harmonic response depends on the contact time and peak contact force. Both quantities are related to the elasticity of the sample. Because the elastic modulus of PS is larger than that of LDPE, oscillating on the PS domain produces a much shorter contact time and a larger peak force in

Nanoprofilometry study of focal conic domain structures in a liquid crystalline free surface

• Anna N. Bagdinova,
• Evgeny I. Demikhov,
• Nataliya G. Borisenko and
• Sergei M. Tolokonnikov

Beilstein J. Nanotechnol. 2017, 8, 2544–2551, doi:10.3762/bjnano.8.254

• is discussed in detail in [4]. Equation 1 is valid in our case because we have a system of FCDs in smectic-A phase. This statement qualitatively corresponds to our results because we observe a slight increase of the FCD depth upon decreasing temperature. The elasticity of the smectic-A liquid crystal

High-speed dynamic-mode atomic force microscopy imaging of polymers: an adaptive multiloop-mode approach

• Juan Ren and
• Qingze Zou

Beilstein J. Nanotechnol. 2017, 8, 1563–1570, doi:10.3762/bjnano.8.158

• two orders of magnitude different lateral feature sizes, ranging from 10 nm (Celgard) to 100 nm (SBS) and up to 2 μm (PS–LDPE), respectively. The elasticity also differs over two orders of magnitude, ranging from 20 MPa (SBS) to 2 GPa (PS). These samples, with largely heterogeneous mechanical

• round dots are made of LDPE, and the rest is PS, with the elasticity of PS and LDPE being 2 GPa and 100 MPa, respectively. However, this information was not discernible in the 2.5 Hz TM phase image (see Figure 1(b4)). Therefore, AMLM imaging yielded high-quality dynamic-mode imaging, and clearly

Parylene C as a versatile dielectric material for organic field-effect transistors

• Tomasz Marszalek,
• Maciej Gazicki-Lipman and
• Jacek Ulanski

Beilstein J. Nanotechnol. 2017, 8, 1532–1545, doi:10.3762/bjnano.8.155

• electronics. The properties of greatest importance for such applications are the extraordinary purity and chemical inertness of Parylene layer, its elasticity and ability to form smooth and pinhole-free conformal coatings. Due to high purity and low dielectric permittivity, the concentration of charge-carrier

3D continuum phonon model for group-IV 2D materials

• Morten Willatzen,
• Lok C. Lew Yan Voon,
• Appala Naidu Gandi and
• Udo Schwingenschlögl

Beilstein J. Nanotechnol. 2017, 8, 1345–1356, doi:10.3762/bjnano.8.136

• , we compare them to DFT calculations. The continuum theory will require as input elasticity constants, piezoelectric coefficients, and dielectric functions. DFT We first give the standard phonon dispersion relation as obtained from DFT calculations (Figure 1). They are obtained from first principles

• modes near the Γ point are shown. Continuum model: MoS2 For single-layer MoS2, we use the following parameters: c11d = 140 Pa·m, c12d = 33 Pa·m, c13d=-0.013 Pa·m, c33d = 0.078 Pa·m, c44d = −1.07 Pa·m, c66d = 53.7 Pa·m, d = 6.2·10−10 m, ρ2D = 3.1 ·10−6 kg/m2, ex1 = 0.5 C/m2. These elasticity parameters

• -principles, continuum elasticity theory was developed for two-dimensional materials. Piezoelectric materials required the simultaneous consideration of the electrostatics equations. Application to graphene, silicene and MoS2 revealed a number of interesting results. The out-of-plane vibrations were coupled

Hierarchically structured nanoporous carbon tubes for high pressure carbon dioxide adsorption

• Julia Patzsch,
• Deepu J. Babu and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2017, 8, 1135–1144, doi:10.3762/bjnano.8.115

• show outstanding elasticity and mechanical strength. A Young’s modulus of 600 GPa was measured for SiC wires [18][19]. Different templating methods were used for structuring such as the two-step synthesis using preceramic polymers as precursors (e.g., polycarbosilanes) [13][20][21], carbo-thermal

Dispersion of single-wall carbon nanotubes with supramolecular Congo red – properties of the complexes and mechanism of the interaction

• Anna Jagusiak,
• Barbara Piekarska,
• Tomasz Pańczyk,
• Małgorzata Jemioła-Rzemińska,
• Elżbieta Bielańska,
• Barbara Stopa,
• Grzegorz Zemanek,
• Janina Rybarska,
• Irena Roterman and
• Leszek Konieczny

Beilstein J. Nanotechnol. 2017, 8, 636–648, doi:10.3762/bjnano.8.68

• CR-dispersed SWNTs (obtained at 5:1 CR/SWNT ratio) analysing mechanical parameters such as elasticity, adhesion, dispersion (dissipation energy) and deformation (Figure 11). Cholate dispersed SWNTs form a monolayer at the mica surface (Figure 11.1) while SWNT–CR complexes form a thick layer with

• single nanotubes protruding above its surface (Figure 11.2). This can be explained by gel-like properties of the complex formed at high CR/SWNT ratio (see Figure 5B,C), which is a network of nanotubes and supramolecular CR. Elasticity measured as the stiffness range is specified in arbitrary relative

• units. Elasticity reached of about 200 mArb on the free SWNT (black) compared to mica layer (red) (Figure 11.1A). In Figure 11.2A we observed a thick layer of SWNTs covered by CR with elasticity of about 450 mArb, but also bulbs which show much lower stiffness and higher plasticity. These bulbs were