Integration of sharp silicon nitride tips into high-speed SU8 cantilevers in a batch fabrication process

• Nahid Hosseini,
• Matthias Neuenschwander,
• Oliver Peric,
• Santiago H. Andany,
• Jonathan D. Adams and
• Georg E. Fantner

Beilstein J. Nanotechnol. 2019, 10, 2357–2363, doi:10.3762/bjnano.10.226

• frequency for a rectangular cantilever with homogenous material properties and no external load is given by where E is the elastic modulus, I the second moment of area, ρ the density and A the cross-sectional area of the cantilever beam. Thus, the resonance frequency depends on the properties of the

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

Improvement of the thermoelectric properties of a MoO₃ monolayer through oxygen vacancies

• Wenwen Zheng,
• Wei Cao,
• Ziyu Wang,
• Huixiong Deng,
• Jing Shi and
• Rui Xiong

Beilstein J. Nanotechnol. 2019, 10, 2031–2038, doi:10.3762/bjnano.10.199

• of the relaxation time τ, we apply the deformation potential (DP) theory [25] where τ is estimated by τ = μm*/e. The carrier mobility μ2D in 2D materials is given by Where m* is the effective mass and md is the density of states (DOS) mass determined by E1 is the DP constant and C2D is the elastic

• modulus. All parameters corresponding to the carrier mobility and the effective mass are taken from [17] and summarized in Table 1. As for phononic transport properties, we calculate the thermal conductivity of the lattice using the Boltzmann transport theory as implemented in the Quantum ESPRESSO (QE

Development of a new hybrid approach combining AFM and SEM for the nanoparticle dimensional metrology

• Loïc Crouzier,
• Alexandra Delvallée,
• Sébastien Ducourtieux,
• Laurent Devoille,
• Guillaume Noircler,
• Christian Ulysse,
• Olivier Taché,
• Elodie Barruet,
• Christophe Tromas and
• Nicolas Feltin

Beilstein J. Nanotechnol. 2019, 10, 1523–1536, doi:10.3762/bjnano.10.150

• defined by: where K the equivalent elastic modulus of the NP and the substrate defined by: where Ei and νi are the Young’s modulus and the Poisson’s ratio of the sphere and the half space. The depth of indentation δ, i.e., the elastic displacement is defined by: In the case of silica NPs deposited on a Si

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

• amplitude signal was observed when scanning over a covered step on the same surface. These observations qualitatively indicate that there is a variation in the elastic modulus over uncovered steps and no variation over covered ones. The quantitative results of the elastic modulus required the use of FMM

• , while the CR mode better highlighted areas of reduced elastic modulus (although it was difficult to convert the data into a quantifiable modulus). In the FMM measurements, single atomic steps of graphene with uncovered step edges showed a decrease in the elastic modulus of approximately 0.5%, which is

• compared with no change in the elastic modulus for covered steps. The analysis of the experimental data taken under varying normal loads and with several different tips showed that the elastic modulus determination was unaffected by these parameters. Keywords: atomic force microscopy; contact resonance

Mechanical and thermodynamic properties of Aβ₄₂, Aβ₄₀, and α-synuclein fibrils: a coarse-grained method to complement experimental studies

• Adolfo B. Poma,
• Horacio V. Guzman,
• Mai Suan Li and
• Panagiotis E. Theodorakis

Beilstein J. Nanotechnol. 2019, 10, 500–513, doi:10.3762/bjnano.10.51

• YT being the transversal Young modulus and h being the indentation depth). If it actually follows this relationship, then the elastic modulus can be easily obtained from the slope of the curve. This approach can be used to test the experimental estimation of an elastic property. Most importantly, the

• dominated by extended regions of amorphous aggregates. Such regions will induce the overall softening of the fibril and therefore a drop in the elastic modulus. Figure 5b shows the distributions of the characteristic native distances (see Figure 2 for their definition). For β-amyloid and α-synuclein fibrils

Gold nanoparticles embedded in a polymer as a 3D-printable dichroic nanocomposite material

• Lars Kool,
• Anton Bunschoten,
• Aldrik H. Velders and
• Vittorio Saggiomo

Beilstein J. Nanotechnol. 2019, 10, 442–447, doi:10.3762/bjnano.10.43

• envision a drastic change in the mechanical properties between pure PVA and AuNP–PVA. To test this, we 3D-printed dog-bone-shaped strips of plastic (2.5 × 0.4 × 0.1 cm) and tested the elastic modulus (Young’s modulus) using dynamic mechanical analysis (DMA). The pure PVA and the AuNP–PVA, as expected, did

• not show significant differences in the elastic modulus giving an average of 3.5 ± 0.8 MPa and 3.8 ± 0.6 MPa, respectively (Figure 2c). The relatively high standard deviation error is given by the intrinsic layer-by-layer 3D fabrication method. The filament was used for printing different “21st

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

• between the adhesive and the substrate, in the form of intermolecular forces, capillary forces, and suction forces. To achieve intimate contact between the adhesive and the substrate, researchers have been designing micropatterned adhesives with a low effective elastic modulus Eeff [6]. For example, micro

• microstructures of dimples with a terminal layer, deformation of the terminal layer is likely to happen, given that the elastic modulus of PDMS is in the kilopascal-range, and thus elastic, and the thickness of the terminal layer is limited (i.e., conformation to substrate roughness requires only a small volume

• samples from sub-microscale particles were characterized with atomic force microscopy (AFM), optical microscopy, and scanning electron microscopy (SEM). Monolayers and samples from microscale particles were characterized with optical microscopy and SEM. The elastic modulus of the fabricated micropatterns

Ternary nanocomposites of reduced graphene oxide, polyaniline and hexaniobate: hierarchical architecture and high polaron formation

• Claudio H. B. Silva,
• Maria Iliut,
• Christopher Muryn,
• Christian Berger,
• Zachary Coldrick,
• Vera R. L. Constantino,
• Marcia L. A. Temperini and
• Aravind Vijayaraghavan

Beilstein J. Nanotechnol. 2018, 9, 2936–2946, doi:10.3762/bjnano.9.272

• , materials comprising all three components can be expected to show improved properties. Since its discovery in 2004, graphene has been proposed for a wide range of applications due to its supreme values of specific surface area, electronic mobility, thermal and electrical conductivities and elastic modulus

The effect of flexible joint-like elements on the adhesive performance of nature-inspired bent mushroom-like fibers

• Elliot Geikowsky,
• Serdar Gorumlu and
• Burak Aksak

Beilstein J. Nanotechnol. 2018, 9, 2893–2905, doi:10.3762/bjnano.9.268

• packed, tilted and curved fibers of various dimensions to attach to surfaces. While the high elastic modulus of these fibers enables an extremely large number of fibers per unit area, where each fiber stands freely without sticking to its neighbors, the tilt/curvature provides them with the compliance

• and the directional adhesion properties to attach strongly and efficiently to a surface. Recent studies have revealed that many of such organisms also feature materials with a graded elastic modulus that is tailored towards improving the contact area without sacrificing the fiber density. In

• particular, for male ladybird beetles, research has shown that the adhesive setae feature a material gradient such that the elastic modulus of the material at the junction between the stalk and the divergent distal end is close to minimum. This soft material acts like a flexible joint, improving the bending

Friction reduction through biologically inspired scale-like laser surface textures

• Johannes Schneider,
• Vergil Djamiykov and
• Christian Greiner

Beilstein J. Nanotechnol. 2018, 9, 2561–2572, doi:10.3762/bjnano.9.238

• chosen that resulted in regular, elliptical protrusions, lowering friction compared to an untextured control sample [24]. In an approach resulting in surface textures much closer to the natural example, Baum et al. showed that variations in the effective elastic modulus (therefore allowing for damping

Adhesive contact of rough brushes

• Qiang Li and
• Valentin L. Popov

Beilstein J. Nanotechnol. 2018, 9, 2405–2412, doi:10.3762/bjnano.9.225

• elastic modulus, E is Young’s modulus, ν is Poisson’s ratio, γ is the work of separation (work of adhesion) per unit area, and is an effective radius of the square, defined so that the area of a cylinder with the radius a0 is equal to the area of the square. Note that the maximum adhesive force for a flat

• dependence of the elastic modulus on depth, such as where E0 is a characteristic elastic modulus and c0 is a characteristic length. We additionally assume that the Poisson’s ratio of the graded medium is constant and consider only a positive k, which means that the material is softer at the surface and

• , and the force of adhesion can be easily written in an explicit form: The factors determining the force of adhesion are thus: elastic modulus E*, work of adhesion γ, size of the contact a0 and normalized roughness l / dcrit. In the case of power-law-graded materials, the situation may change

Fabrication of photothermally active poly(vinyl alcohol) films with gold nanostars for antibacterial applications

• Mykola Borzenkov,
• Maria Moros,
• Claudia Tortiglione,
• Serena Bertoldi,
• Nicola Contessi,
• Silvia Faré,
• Angelo Taglietti,
• Agnese D’Agostino,
• Piersandro Pallavicini,
• Maddalena Collini and
• Giuseppe Chirico

Beilstein J. Nanotechnol. 2018, 9, 2040–2048, doi:10.3762/bjnano.9.193

• stress–strain curves of the three types of films followed the same trend, however being characterized by different elastic modulus, maximum stress and maximum strain values. In particular, PVA films without GNSs showed the lowest stiffness value in comparison with both types of PVA-GNS films (p < 0.05

• . Tests were performed at 37 °C by applying a ramp force of 1 N/min up to 18 N (force limit of DMA instrument). The elastic modulus (E), calculated considering the strain range 0–10%, maximum stress (σmax) and maximum strain (εmax) were drawn from the stress–strain curve elaboration and expressed as mean

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

• minimum of energy dissipation. In this case, the low friction is depending on the high elastic modulus of graphene, which ensures that the graphene lattice remains nearly unaltered relative to the gold lattice. Therefore, an incommensurate contact is maintained during movement along the gold surface. An

Defect formation in multiwalled carbon nanotubes under low-energy He and Ne ion irradiation

• Santhana Eswara,
• Jean-Nicolas Audinot,
• Brahime El Adib,
• Maël Guennou,
• Tom Wirtz and
• Patrick Philipp

Beilstein J. Nanotechnol. 2018, 9, 1951–1963, doi:10.3762/bjnano.9.186

• irradiation is part of these studies [2]. Irradiation-induced defects affect the elastic modulus and the tensile strength of CNTs [3]. For example, for multiwalled carbon nanotubes (MWCNTs), the presence of a small number of defects can increase the interlayer shear strength by several orders of magnitude [4

• carbon-based materials. It has been used to study the influence of the twist angle in combination with defects of bi-layered graphene on the Raman peaks [25], to correlate ion irradiation to the number of defects and the change in elastic modulus [7], the comparison of C+ and Ni+ ion irradiation for

Synthesis of hafnium nanoparticles and hafnium nanoparticle films by gas condensation and energetic deposition

• Irini Michelakaki,
• Nikos Boukos,
• Dimitrios A. Dragatogiannis,
• Spyros Stathopoulos,
• Costas A. Charitidis and
• Dimitris Tsoukalas

Beilstein J. Nanotechnol. 2018, 9, 1868–1880, doi:10.3762/bjnano.9.179

• . Nanomechanical properties and porosity of Hf NTFs Hardness (H) and elastic modulus (E) of the nanocrystalline porous Hf NTFs were determined by nanoidentation measurements. (The load–displacement curves of Hf NTFs are presented in Supporting Information File 1, Section 3.) For comparison, the hardness and

• elastic modulus of a radio-frequency (RF)-sputtered 120 nm thick Hf film, was measured with the same technique as the NTFs. When Vs = 0 kV, elastic modulus and hardness are E = 33.6 GPa and H = 0.45 GPa, respectively. With increasing substrate voltage the mechanical properties are improved. For Vs = 2 kV

• , elastic modulus and hardness increase to E = 40.4 GPa and H = 2 GPa, respectively. For Vs = 4.5 kV, further increments to E = 65.8 GPa and H = 9.1 GPa are observed. These values tend to approach the mechanical properties of the RF-sputtered Hf film, which are E = 94.5 GPa and H = 12 GPa. The results are

Preparation of micro/nanopatterned gelatins crosslinked with genipin for biocompatible dental implants

• Reika Makita,
• Tsukasa Akasaka,
• Seiichi Tamagawa,
• Yasuhiro Yoshida,
• Saori Miyata,
• Hirofumi Miyaji and
• Tsutomu Sugaya

Beilstein J. Nanotechnol. 2018, 9, 1735–1754, doi:10.3762/bjnano.9.165

• of biological tissues and for the reinforcement of scaffolds. Genipin has low toxicity, being about 10,000 times less cytotoxic than other crosslinking agents, such as glutaraldehyde [47]. Crosslinking with genipin has been shown to result in an improvement in tensile strength, elastic modulus, and

Electro-optical interfacial effects on a graphene/π-conjugated organic semiconductor hybrid system

• Karolline A. S. Araujo,
• Luiz A. Cury,
• Matheus J. S. Matos,
• Thales F. D. Fernandes,
• Luiz G. Cançado and
• Bernardo R. A. Neves

Beilstein J. Nanotechnol. 2018, 9, 963–974, doi:10.3762/bjnano.9.90

• peak force or tapping mode. Besides conventional topographic images, peak force mode yields several concomitant images which map mechanical properties of the sample, like adhesion, elastic modulus, dissipation and others [64]. The adhesion channel monitors tip–sample attractive forces along the imaging

Effect of annealing treatments on CeO₂ grown on TiN and Si substrates by atomic layer deposition

• Silvia Vangelista,
• Rossella Piagge,
• Satu Ek and
• Alessio Lamperti

Beilstein J. Nanotechnol. 2018, 9, 890–899, doi:10.3762/bjnano.9.83

• deposition process. This result is interpreted in the light of the contributions of different energy components (surface energy and elastic modulus) which act dependently on the substrate properties, such as its nature and structure. Keywords: atomic layer deposition; cerium(IV) oxide (CeO2) microstructure

Single-step process to improve the mechanical properties of carbon nanotube yarn

• Maria Cecilia Evora,
• Xinyi Lu,
• Nitilaksha Hiremath,
• Nam-Goo Kang,
• Kunlun Hong,
• Roberto Uribe,
• Gajanan Bhat and
• Jimmy Mays

Beilstein J. Nanotechnol. 2018, 9, 545–554, doi:10.3762/bjnano.9.52

• elastic modulus increases with crosslinking while the strain decreases significantly when CNT yarns are modified. Untreated samples exhibit lower strength but higher strain because of slippage of the CNTs. The strain is reduced due to enhancement in the CNTs interaction because of the crosslinking process

• . After the treatment of the yarn samples, load transfer and strength increase. The crosslinking process strongly affects the strength and elastic modulus [45]. The untreated CNT yarn demonstrates a strength of 251.09 ± 26.52 MPa and a modulus of 8.79 ± 1.19 GPa The modification of the CNT yarn structure

• with PAN improved the strength to 347.94 ± 66.36 MPa and the modulus to 15.38 ± 1.19 GPa, because of the crosslinking that probably occurred at the nitrogen atom of the =C=N– functionality [46]. These results show an increase of about 38.6% in strength and about 75% in elastic modulus. The biggest

Ultralight super-hydrophobic carbon aerogels based on cellulose nanofibers/poly(vinyl alcohol)/graphene oxide (CNFs/PVA/GO) for highly effective oil–water separation

• Zhaoyang Xu,
• Huan Zhou,
• Sicong Tan,
• Xiangdong Jiang,
• Weibing Wu,
• Jiangtao Shi and
• Peng Chen

Beilstein J. Nanotechnol. 2018, 9, 508–519, doi:10.3762/bjnano.9.49

• on the planet because of its biodegradability, sustainability, nontoxic nature, and biocompatibility [5]. Cellulose nanofibers (CNFs) derived from cellulose have gained wide attention due to their outstanding mechanical properties [6][7] such as an elastic modulus of 140 GPa [8]. In an aqueous

BN/Ag hybrid nanomaterials with petal-like surfaces as catalysts and antibacterial agents

• Konstantin L. Firestein,
• Denis V. Leybo,
• Alexander E. Steinman,
• Andrey M. Kovalskii,
• Andrei T. Matveev,
• Anton M. Manakhov,
• Irina V. Sukhorukova,
• Pavel V. Slukin,
• Nadezda K. Fursova,
• Sergey G. Ignatov,
• Dmitri V. Golberg and
• Dmitry V. Shtansky

Beilstein J. Nanotechnol. 2018, 9, 250–261, doi:10.3762/bjnano.9.27

• effects of different nanocomponents. In recent years, BN nanostructures have been in the focus due to advantageous combination of properties, such as high tensile strength and elastic modulus, superb chemical stability, biocompatibility, high thermal conductivity and perfect electrical insulation. This

Liquid-crystalline nanoarchitectures for tissue engineering

• Baeckkyoung Sung and
• Min-Ho Kim

Beilstein J. Nanotechnol. 2018, 9, 205–215, doi:10.3762/bjnano.9.22

• tissue by altering the elastic modulus of tissue [58]. Hard tissues Skeletal tissues are mineralized compact matrices of ordered biopolymers [59]. In vertebrates, bones consist of a dense mesophase of collagen fibrils [60], which has been believed to render mechanical stiffness to the skeletal tissues

• induced 2D and 3D aligned cell growth in response to the lamellar molecular structure of LCE matrices, with tunable porosity and crosslinking density [99][100][101]. In addition, the 3D anisotropic cell scaffolds can be fabricated by using nematic LCE microspheres as building blocks by tuning elastic

• modulus, porosity, surface roughness, and local anisotropy [102]. LC hydrogels and implants in nematic and smectic-A phases LC-ordered anisotropic gels have great potential to be directly applied to regenerative medicine therapeutics, due to their intrinsic tissue compatibility. Thermally or

Humidity-dependent wound sealing in succulent leaves of Delosperma cooperi – An adaptation to seasonal drought stress

• Olga Speck,
• Mark Schlechtendahl,
• Florian Borm,
• Tim Kampowski and
• Thomas Speck

Beilstein J. Nanotechnol. 2018, 9, 175–186, doi:10.3762/bjnano.9.20

• mechanically important parameters. Mechanical properties of the entire leaf and of single tissue layers were measured in tensile tests, which provided the basis for calculating the elastic modulus and tensile strength. The elastic modulus of the epidermis in transversal and longitudinal directions was not

• significantly different (Wilcoxon Mann-Whitney signed rank test, W = 38, p > 0.05), whereas the tensile strength differed significantly (Wilcoxon Mann-Whitney signed rank test, W = 19.5, p < 0.05). On the basis of Equation 7 (presented later in this work), we calculated the elastic modulus of the parenchyma and

• diameter dc = 77 µm, cell wall thickness tcw = 0.42 µm and Poisson’s ratio v = 0.28 and by using an elastic modulus of cell walls Ecw = 5.00 MPa [15], an elastic modulus of 0.25 MPa was calculated for the parenchyma and chlorenchyma. Poisson’s ratio from entire leaves was calculated from pictures taken

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

• relation exists when measuring in contact mode with a certain load FN and propose a new method for determining the elastic modulus of samples from this relation. The measurements were performed in non-dry air at ambient temperature on three different polymers (polystyrene, polypropylene and linear low

• elastic modulus from Δf22/Δf1. The method was used to give an estimate of the Young’s modulus of the FDTS thin film. Keywords: atomic force microscopy; contact resonances; elastic modulus; 1H,1H,2H,2H-perfluorodecyltrichlorosilane (FDTS); polymers; Young’s modulus; Introduction Knowledge of the local

• 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