Molecular dynamics simulations of mechanical failure in polymorphic arrangements of amyloid fibrils containing structural defects

• Hlengisizwe Ndlovu,
• Alison E. Ashcroft,
• Sheena E. Radford and
• Sarah A. Harris

Beilstein J. Nanotechnol. 2013, 4, 429–440, doi:10.3762/bjnano.4.50

•  5. All three fibril polymorphs demonstrate an anisotropic response to mechanical probing. Similar mean peak forces are required to break the fibrils when the hydrogen-bond networks are probed (“shear” and “stretch”). There are however, very distinct responses in the SMD simulations that probe the

A highly pH-sensitive nanowire field-effect transistor based on silicon on insulator

• Denis E. Presnov,
• Sergey V. Amitonov,
• Pavel A. Krutitskii,
• Valentina V. Kolybasova,
• Igor A. Devyatov,
• Vladimir A. Krupenin and
• Igor I. Soloviev

Beilstein J. Nanotechnol. 2013, 4, 330–335, doi:10.3762/bjnano.4.38

• and contact pads. Aluminium mask e-beam vapour deposition. Anisotropic reactive ion etching of the device layer through the Al mask and mask removal. Magnetron sputtering of titanium electrodes and their isolation with silica to allow measurements in liquids. Both optical and electron-beam lithography

Grating-assisted coupling to nanophotonic circuits in microcrystalline diamond thin films

• Patrik Rath,
• Svetlana Khasminskaya,
• Christoph Nebel,
• Christoph Wild and
• Wolfram H.P. Pernice

Beilstein J. Nanotechnol. 2013, 4, 300–305, doi:10.3762/bjnano.4.33

• thin film by reactive ion etching (RIE) on an Oxford 80 system. We use oxygen/argon chemistry at high bias voltage in order to obtain highly anisotropic etching. Typical etch rates are around 25 nm/min, allowing us to precisely reach a desired etch depth. A false-colour SEM image of a typical ridge

• that the etch recipe is indeed highly anisotropic. Also visible in the image is the residual e-beam resist (labelled HSQ for Hydrogen silsesquioxane) on top of the waveguide. Design of focussing grating couplers We fabricate nanophotonic waveguides with a width of 1000 nm using the procedure outlined

Hydrogen-plasma-induced magnetocrystalline anisotropy ordering in self-assembled magnetic nanoparticle monolayers

• Alexander Weddemann,
• Judith Meyer,
• Anna Regtmeier,
• Irina Janzen,
• Dieter Akemeier and
• Andreas Hütten

Beilstein J. Nanotechnol. 2013, 4, 164–172, doi:10.3762/bjnano.4.16

• ) that switch as a whole entails hard shoulders in the hysteresis curves. (c) The assumption of a perfect grid entails anisotropic response functions [31]. In the experimental realization, the data resemble the average taken over all measuring directions due to arbitrarily oriented particle grains

Characterization and properties of micro- and nanowires of controlled size, composition, and geometry fabricated by electrodeposition and ion-track technology

• Maria Eugenia Toimil-Molares

Beilstein J. Nanotechnol. 2012, 3, 860–883, doi:10.3762/bjnano.3.97

• etching solution the ion tracks can be selectively dissolved and subsequently enlarged into channels [39]. For the successful fabrication of templates, the anisotropic dissolution rate along the ion track (Vt) must be higher than the dissolution rate of the undamaged bulk material (Vb). The material of

• these thermoelectric nanomaterials should increase due to quantum size effects and the thermal conductivity should decrease due to enhanced phonon surface scattering [85][86][87][88]. The thermoelectric properties of these Bi-compound materials are anisotropic and are extremely sensitive not only to

Pure hydrogen low-temperature plasma exposure of HOPG and graphene: Graphane formation?

• Baran Eren,
• Dorothée Hug,
• Laurent Marot,
• Rémy Pawlak,
• Marcin Kisiel,
• Roland Steiner,
• Dominik M. Zumbühl and
• Ernst Meyer

Beilstein J. Nanotechnol. 2012, 3, 852–859, doi:10.3762/bjnano.3.96

• simplicity, εi was taken as 3.6 Te, which is 12.6 ± 1.8 eV in our case. We think that double-sided hydrogenation may be achieved under these plasma conditions. It is also possible to achieve single-surface hydrogenation, anisotropic chemical etching [28] or physical sputtering of HOPG by changing the plasma

Highly ordered ultralong magnetic nanowires wrapped in stacked graphene layers

• Abdel-Aziz El Mel,
• Jean-Luc Duvail,
• Eric Gautron,
• Wei Xu,
• Chang-Hwan Choi,
• Benoit Angleraud,
• Agnès Granier and
• Pierre-Yves Tessier

Beilstein J. Nanotechnol. 2012, 3, 846–851, doi:10.3762/bjnano.3.95

• exhibit a similar crystalline structure. Indeed, in both cases only the 002 reflections corresponding to crystalline hexagonal graphite were present [29][30]. They appear as arcs instead of rings due to the anisotropic nanotexture in the analyzed area [30]. The 004 reflections and hk bands (i.e., 10 and

Tuning the properties of magnetic thin films by interaction with periodic nanostructures

• Ulf Wiedwald,
• Felix Haering,
• Stefan Nau,
• Carsten Schulze,
• Herbert Schletter,
• Denys Makarov,
• Alfred Plettl,
• Karsten Kuepper,
• Manfred Albrecht,
• Johannes Boneberg and
• Paul Ziemann

Beilstein J. Nanotechnol. 2012, 3, 831–842, doi:10.3762/bjnano.3.93

• use of highly anisotropic materials are necessary to be competitive with storage media employing percolated perpendicular media. Principle of percolated perpendicular media. The exchange-coupled film is interspersed by nonmagnetic nanostructures (white dots) allowing domain-wall (black lines) pinning

Pinch-off mechanism in double-lateral-gate junctionless transistors fabricated by scanning probe microscope based lithography

• Farhad Larki,
• Arash Dehzangi,
• Alam Abedini,
• Ahmad Makarimi Abdullah,
• Elias Saion,
• Sabar D. Hutagalung,
• Mohd N. Hamidon and
• Jumiah Hassan

Beilstein J. Nanotechnol. 2012, 3, 817–823, doi:10.3762/bjnano.3.91

• (Vth) between the simulation and experimental curves can be illustrated by the presence of fixed interface charge, work function differences, or both [20]. It should be mentioned that, during the KOH anisotropic etching process, very complicated three-dimensional structures based on the etchant

Ordered arrays of nanoporous gold nanoparticles

• Dong Wang,
• Ran Ji,
• Arne Albrecht and
• Peter Schaaf

Beilstein J. Nanotechnol. 2012, 3, 651–657, doi:10.3762/bjnano.3.74

• acted as a mask during the anisotropic etching of Si in a KOH solution, and the Si surface was patterned into a periodic array of pyramidal pits. After removal of the SiO2 mask, about 20 nm of SiO2 was then again thermally grown on the structured Si surface to avoid a reaction between the subsequently

• thermally grown on the Si wafer. A pattern with an array of holes was defined by SCIL, and then transferred to the SiO2 layer by RIE. The SiO2 pattern with the array of holes acted as a mask during the anisotropic etching of Si in a 40 wt % KOH solution at 60 °C, and a periodic array of pyramidal pits was

Macromolecular shape and interactions in layer-by-layer assemblies within cylindrical nanopores

• Thomas D. Lazzara,
• K. H. Aaron Lau,
• Wolfgang Knoll,
• Andreas Janshoff and
• Claudia Steinem

Beilstein J. Nanotechnol. 2012, 3, 475–484, doi:10.3762/bjnano.3.54

• organic thin layer coating the pore surfaces (i.e., the LbL multilayer film). The dielectric constant is related to the refractive index by ε = n2. εAAO has anisotropic components that are described by the infinite, prolate ellipsoid approximation within the Maxwell–Garnett theory, and well-described

Mesoporous MgTa₂O₆ thin films with enhanced photocatalytic activity: On the interplay between crystallinity and mesostructure

• Jin-Ming Wu,
• Igor Djerdj,
• Till von Graberg and
• Bernd M. Smarsly

Beilstein J. Nanotechnol. 2012, 3, 123–133, doi:10.3762/bjnano.3.13

• crystalline standard. The standard was also used for the deconvolution of the instrumental-broadening contribution. Since the initial refinement gave rather high disagreement between the experimental and calculated curves, particularly in the [103] direction, an anisotropic broadening with a larger

• , suggesting an anisotropic shrinkage of the mesostructure in the direction normal to the substrate, which has often been observed previously [20]. For the SAXS patterns obtained in transmission geometry (β = 90°) the 1,−1,0 ring, corresponding to a random orientation of mesostructured domains of the bcc

Impact of cell shape in hierarchically structured plant surfaces on the attachment of male Colorado potato beetles (Leptinotarsa decemlineata)

• Bettina Prüm,
• Robin Seidel,
• Holger Florian Bohn and
• Thomas Speck

Beilstein J. Nanotechnol. 2012, 3, 57–64, doi:10.3762/bjnano.3.7

• and kettle trap flowers. Plant species from different systematic groups were investigated and classified as to their surface design by Poppinga et al. [12]. Surface structuring, showing anisotropic papillate cells pointing downwards are frequently found in carnivorous plants and kettle trap flowers

STM study on the self-assembly of oligothiophene-based organic semiconductors

• Elena Mena-Osteritz,
• Marta Urdanpilleta,
• Erwaa El-Hosseiny,
• Berndt Koslowski,
• Paul Ziemann and
• Peter Bäuerle

Beilstein J. Nanotechnol. 2011, 2, 802–808, doi:10.3762/bjnano.2.88

• , which are very close to the Fermi level and are coupled, at this bias, to an almost anisotropic contribution from the LDOS of the substrate. In Figure 3, STM images of a 2-D crystal of the next higher homologue, hexamer H6TCOOH, are depicted. Figure 3, left, shows a large-scale STM image of a densely

Interaction of spin and vibrations in transport through single-molecule magnets

• Falk May,
• Maarten R. Wegewijs and
• Walter Hofstetter

Beilstein J. Nanotechnol. 2011, 2, 693–698, doi:10.3762/bjnano.2.75

• Grünberg Institut and JARA - Fundamentals of Information Technology, Forschungszentrum Jülich, 52425 Jülich, Germany 10.3762/bjnano.2.75 Abstract We study electron transport through a single-molecule magnet (SMM) and the interplay of its anisotropic spin with quantized vibrational distortions of the

• the fundamental problem of how a few magnetic atoms in an anisotropic environment respond to an electron current [1]. Such an environment is provided, for instance, by ligand groups holding such atoms together in a single magnetic molecule contacted in a break junction [2][3]. A very similar situation

• -Kondo temperature TK is suppressed too much, reducing both the height and width of the peak (without splitting it). Dynamic anisotropy The anisotropic couplings of the large spin to the vibrational mode D′ and E′ are, however, also of importance [9], especially if the vibrational mode frequency energy Ω

Investigation on structural, thermal, optical and sensing properties of meta-stable hexagonal MoO₃ nanocrystals of one dimensional structure

• Angamuthuraj Chithambararaj and
• Arumugam Chandra Bose

Beilstein J. Nanotechnol. 2011, 2, 585–592, doi:10.3762/bjnano.2.62

• formed during the nucleation stage are composed of hexagonal unit cells which can induce anisotropic growth along the c-axis, and thus hexagonal shaped nanocrystals with 1D structure are favored [24][25]. Thermal analysis The thermal behavior was studied in detail and is depicted in Figure 8. From the TG

Self-organizing bioinspired oligothiophene–oligopeptide hybrids

• Alexey K. Shaytan,
• Eva-Kathrin Schillinger,
• Elena Mena-Osteritz,
• Sylvia Schmid,
• Pavel G. Khalatur,
• Peter Bäuerle and
• Alexei R. Khokhlov

Beilstein J. Nanotechnol. 2011, 2, 525–544, doi:10.3762/bjnano.2.57

• the A–B system 6 in the native state of the peptide. In principle both parts of this hybrid molecule (thiophene part and peptide part) may be capable of strong intermolecular interactions, thus leading to the formation of highly anisotropic structures such as nanofibers, nanorods, etc. However, the IR

Towards multiple readout application of plasmonic arrays

• Dana Cialla,
• Karina Weber,
• René Böhme,
• Uwe Hübner,
• Henrik Schneidewind,
• Matthias Zeisberger,
• Roland Mattheis,
• Robert Möller and
• Jürgen Popp

Beilstein J. Nanotechnol. 2011, 2, 501–508, doi:10.3762/bjnano.2.54

• will also be enhanced due to the plasmon resonance of the nanoantenna. This effect is described as the second part of the electromagnetic SERS mechanism [30][31]. Recently we [24] investigated this contribution of secondary emission enhancement to the overall SERS signal, utilizing the anisotropic

Plasmonic nanostructures fabricated using nanosphere-lithography, soft-lithography and plasma etching

• Manuel R. Gonçalves,
• Taron Makaryan,
• Fabian Enderle,
• Stefan Wiedemann,
• Alfred Plettl,
• Othmar Marti and
• Paul Ziemann

Beilstein J. Nanotechnol. 2011, 2, 448–458, doi:10.3762/bjnano.2.49

• adsorbed on the surface influence the anisotropic etching of quartz (Figure 5). The anisotropic RIE (using ICP-RIE Oxford Plasmanlab 80 Plus) process was applied to transfer the Cr pattern onto the quartz substrate [39][40]. The etching process uses a side wall passivation similar to the Bosch process [38

Micro to nano: Surface size scale and superhydrophobicity

• Christian Dorrer and
• Jürgen Rühe

Beilstein J. Nanotechnol. 2011, 2, 327–332, doi:10.3762/bjnano.2.38

• micromachining Using standard lithographic techniques and reactive ion etching, different patterns of shapes were transferred from a photomask into an oxide layer on 4 inch, silicon (100) wafers. The oxide acted as a masking layer in the subsequent anisotropic etching step, where the actual three-dimensional

The effect of surface anisotropy in the slippery zone of Nepenthes alata pitchers on beetle attachment

• Elena V. Gorb and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2011, 2, 302–310, doi:10.3762/bjnano.2.35

• to the upward one, whereas clawless insects did not. These results led to the conclusion that, (i) due to the particular shape of lunate cells, the pitcher surface has anisotropic properties in terms of insect attachment, and (ii) claws were mainly responsible for attachment enhancement in the

• given in Figure 2. These cells are responsible for the anisotropic surface relief of up to 10 μm in height, whereas crystalline wax coverage creates an additional roughness in the range of about 1 µm. De-waxed pitcher samples and their polymer replicas displayed a very similar surface structure with a

• -waxed samples and their replicas were observed compared to the intact pitchers. Taking into account the relatively low height and aspect ratio of this waviness, it seemed to have no effect on the anisotropic properties of plant surfaces as discussed below. Anisotropy effect on insect attachment Insect

Effect of large mechanical stress on the magnetic properties of embedded Fe nanoparticles

• Srinivasa Saranu,
• Sören Selve,
• Ute Kaiser,
• Luyang Han,
• Ulf Wiedwald,
• Paul Ziemann and
• Ulrich Herr

Beilstein J. Nanotechnol. 2011, 2, 268–275, doi:10.3762/bjnano.2.31

• capacities. This development is associated with the introduction of new technologies, such as the magneto-resistive read heads first based on the anisotropic magneto-resistance (AMR) and later on the giant magneto-resistance (GMR) and tunnel magneto-resistance (TMR) effect. In conventional magnetic thin

Schottky junction/ohmic contact behavior of a nanoporous TiO₂ thin film photoanode in contact with redox electrolyte solutions

• Masao Kaneko,
• Hirohito Ueno and
• Junichi Nemoto

Beilstein J. Nanotechnol. 2011, 2, 127–134, doi:10.3762/bjnano.2.15

• permittivity (ε of TiO2 = 85.8 and 170, anisotropic), ε0 the vacuum permittivity (8.854 × 10−12 F·m−1), q the elementary electric charge (1.602 × 10−19 C), N the carrier density [m−3], E the applied potential [V], Efb the flat band potential [V], kB the Boltzman constant (1.380 × 10−23 J·K−1), and T the

• Equation 2, the flat band potential Efb, carrier density N, and the thickness of space charge layer dsc were calculated and are shown in Table 1. For the calculation, since the relative permittivity ε of TiO2 is anisotropic (85.8 and 170), we used both the values in the calculation, and thereafter took

Structure, morphology, and magnetic properties of Fe nanoparticles deposited onto single-crystalline surfaces

• Armin Kleibert,
• Wolfgang Rosellen,
• Mathias Getzlaff and
• Joachim Bansmann

Beilstein J. Nanotechnol. 2011, 2, 47–56, doi:10.3762/bjnano.2.6

• supported by or be embedded into a suitable medium. Many studies showed that the cluster–substrate interaction has an tremendous impact on the resulting magnetic properties. The physical origin of such a behavior may be caused, e.g., by strain effects resulting from the interface or a (often anisotropic

Ultrafine metallic Fe nanoparticles: synthesis, structure and magnetism

• Olivier Margeat,
• Marc Respaud,
• Catherine Amiens,
• Pierre Lecante and
• Bruno Chaudret

Beilstein J. Nanotechnol. 2010, 1, 108–118, doi:10.3762/bjnano.1.13

• contribution should be anisotropic, which could explain the large effective magnetic anisotropy measured in these particles. Oriented NPs would be necessary to investigate this latter phenomenon. Conclusion Systems of well isolated metallic Fe NPs with diameters of less than 2 nm and embedded in a polymer have