Phenalenyl-based mononuclear dysprosium complexes

• Yanhua Lan,
• Andrea Magri,
• Olaf Fuhr and
• Mario Ruben

Beilstein J. Nanotechnol. 2016, 7, 995–1009, doi:10.3762/bjnano.7.92

• , respectively. However, due to the incomplete saturation of the magnetization, a residual slope is observed at high fields indicating the presence of magnetic anisotropy in the material [48][49]. Moreover, no hysteresis effect is observed in all three cases under these conditions. Dynamic magnetic properties As

Synthesis of cobalt nanowires in aqueous solution under an external magnetic field

• Xiaoyu Li,
• Lijuan Sun,
• Hu Wang,
• Kenan Xie,
• Qin Long,
• Xuefei Lai and
• Li Liao

Beilstein J. Nanotechnol. 2016, 7, 990–994, doi:10.3762/bjnano.7.91

• diffraction mottling were shown in each SAED pattern, which demonstrated that the resultant nanowires possessed crystal structure and PVP had only little impact on that. Figure 4 displays the hysteresis loop measured at room temperature under an applied magnetic field of up to 25000 Oe for the PVP-protected

• cobalt nanowires obtained in aqueous solution under an external magnetic field of 40 mT. An expanded plot is shown in the insert for field strengths between −6000 Oe and 6000 Oe. The hysteresis loop suggested that the synthesized cobalt nanowires were ferromagnetic at room temperature, which differs from

• nanowires prepared with PVP (c) and without PVP (d). The hysteresis loop of the PVP-protected cobalt nanowires prepared under an external magnetic field measured at room temperature. The inset shows the respective expanded plots for fields between −6000 and 6000 Oe. Acknowledgements Financial supports by

Thickness dependence of the triplet spin-valve effect in superconductor–ferromagnet–ferromagnet heterostructures

• Daniel Lenk,
• Vladimir I. Zdravkov,
• Jan-Michael Kehrle,
• Günter Obermeier,
• Aladin Ullrich,
• Roman Morari,
• Hans-Albrecht Krug von Nidda,
• Claus Müller,
• Mikhail Yu. Kupriyanov,
• Anatolie S. Sidorenko,
• Siegfried Horn,
• Rafael G. Deminov,
• Lenar R. Tagirov and
• Reinhard Tidecks

Beilstein J. Nanotechnol. 2016, 7, 957–969, doi:10.3762/bjnano.7.88

• increasingly hard to evaluate, the thinner the Cu41Ni59 layer is. We should remark, that the present reconstruction of the hysteresis loop is not unambiguous. Moreover, it shows small deviations from the data, especially for the positive sweep direction around H = 0. Possibly, these deviations can be reduced

• by the extended version of the model of Geiler and co-workers [62]. However, this requires the inclusion of three additional fit parameters per layer and sweep direction. This fact, in conjunction with the lack of clear structures in the hysteresis loop, yields mutual dependencies of the parameters

• and, thus, renders the extended model inapplicable. Moreover, even in the simple version of the model, the obtained parameters include an estimated error of about ±10% for ms and ±(10–20)% for the other parameters. Investigations of the hysteresis loops of (Cu41Ni59/Si) × 4 samples show that the

Magnetic switching of nanoscale antidot lattices

• Ulf Wiedwald,
• Joachim Gräfe,
• Kristof M. Lebecki,
• Maxim Skripnik,
• Felix Haering,
• Gisela Schütz,
• Paul Ziemann,
• Eberhard Goering and
• Ulrich Nowak

Beilstein J. Nanotechnol. 2016, 7, 733–750, doi:10.3762/bjnano.7.65

• uniaxial anisotropy with same axis but opposite value of the shape anisotropy. Using this procedure, the shape anisotropy is cancelled out and our simulations are closer to the experiments. During hysteresis, domain nucleation will turn out to be an important factor affecting the reversal process [27]. As

• switching of in-plane magnetized antidot films Integral magnetic properties In this section, we present the magnetic hysteresis loops of Fe, Co, and Py antidot films of varying antidot diameter d as determined by SQUID magnetometry. These integral results – averaged over the thousands of structural domains

• of the antidot lattice – serve as a starting point for the following discussion of microscopic switching mechanisms obtained from magnetic microscopy techniques and micromagnetic simulations. Figure 5a presents the normalized magnetic hysteresis loops of Fe antidot films with d = 45 nm, 140 nm, 160

Coupled molecular and cantilever dynamics model for frequency-modulated atomic force microscopy

• Michael Klocke and
• Dietrich E. Wolf

Beilstein J. Nanotechnol. 2016, 7, 708–720, doi:10.3762/bjnano.7.63

• separately or simultaneously depending on the tip position. These mechanisms are adhesion hysteresis on the one hand and lateral excitations of the cantilever on the other. We find that the short range Lennard-Jones part of the atomic interaction alone is sufficient for changing the predominant mechanism

• . When the long range ionic interaction is switched off, the two damping mechanisms occur with a completely different pattern, which is explained by the energy landscape for the apex atom of the tip. In this case the adhesion hysteresis is always associated with a distinct lateral displacement of the tip

• of the dissipation signal in frequency-modulated atomic force microscopy (FM-AFM) was unclear for a long time, and different effects had been discussed, before it was shown that the main contribution comes from adhesion hysteresis [1][2][3]. However, agreement between theoretical predictions and

Cantilever bending based on humidity-actuated mesoporous silica/silicon bilayers

• Christian Ganser,
• Gerhard Fritz-Popovski,
• Roland Morak,
• Parvin Sharifi,
• Benedetta Marmiroli,
• Barbara Sartori,
• Heinz Amenitsch,
• Thomas Griesser,
• Christian Teichert and
• Oskar Paris

Beilstein J. Nanotechnol. 2016, 7, 637–644, doi:10.3762/bjnano.7.56

• adsorption and after desorption. Such an offset points to an only partially reversible process and perhaps also to slight drift problems. A clear hysteresis is evident between the adsorption and desorption curves above RH = 50%. This hysteresis in cantilever deflection agrees with the hysteresis seen in

• fluids leads to a non-monotonous deformation of mesoporous materials [12][13]. In particular the so-called strain-isotherm, i.e., the deformation of the porous material as a function of relative fluid pressure, exhibits a similar hysteresis as the sorption isotherm. The observed cantilever bending is

Correlative infrared nanospectroscopic and nanomechanical imaging of block copolymer microdomains

• Benjamin Pollard and
• Markus B. Raschke

Beilstein J. Nanotechnol. 2016, 7, 605–612, doi:10.3762/bjnano.7.53

• measure a dissipation (Figure 3g) of 25 eV over PMMA, and 45 eV over PS. The dissipation channel measures the integrated hysteresis between approach and retract and thus directly measures the energy lost to the sample. For purely elastic behavior, the energy loss is dominated by adhesive forces associated

Nanoscale effects in the characterization of viscoelastic materials with atomic force microscopy: coupling of a quasi-three-dimensional standard linear solid model with in-plane surface interactions

• Santiago D. Solares

Beilstein J. Nanotechnol. 2016, 7, 554–571, doi:10.3762/bjnano.7.49

• also worth emphasizing the counterintuitive observation that in Figure 8a the force curves corresponding to a larger 2D surface elastic modulus (which Figure 8f indicates lead to shallower indentations) exhibit the largest amount of dissipation (they have hysteresis loops of larger area [14]). This is

• interesting to note that not only the steepness and the area of the dissipation hysteresis loop changes, but also the maximum attractive force (“well depth” of the curves) can vary. This is because different tip profiles lead to different proximity between the surface elements and the surface of the tip, thus

Contact-free experimental determination of the static flexural spring constant of cantilever sensors using a microfluidic force tool

• John D. Parkin and
• Georg Hähner

Beilstein J. Nanotechnol. 2016, 7, 492–500, doi:10.3762/bjnano.7.43

• speed, was first increased and then decreased in the experiment. A slight hysteresis can be observed in the deflection curve for fluid speeds below ≈15 m/s, corresponding to pressure values of <0.8 kPa. To properly normalize the curve to zero deflection, the photodiode signal value at very low speeds

• experienced by the cantilever is due to plan-view-dependent drag as opposed to viscous shear, and the former is not significantly influenced by the presence of the tip. The reason for the observed hysteresis in the speed-dependent deflection (Figure 5) is not entirely clear. Some cantilevers showed no

• hysteresis at all while others showed more pronounced hysteresis, in particular Tap525. A change in the alignment of the cantilever relative to the channel had no effect on the observed phenomenon. The hysteresis could be related to changes in the humidity surrounding the cantilever as the fluid flow of dry

Charge and heat transport in soft nanosystems in the presence of time-dependent perturbations

• Alberto Nocera,
• Carmine Antonio Perroni,
• Vincenzo Marigliano Ramaglia and
• Vittorio Cataudella

Beilstein J. Nanotechnol. 2016, 7, 439–464, doi:10.3762/bjnano.7.39

• consequence, intriguing nonlinear phenomena, such as hysteresis, switching, and negative differential conductance have been observed in molecular junctions. In conducting molecules, either the center of mass oscillations [9], or thermally induced acoustic phonons [10] can be the source of coupling between

• of gigahertz. Recently, it has been found that phenomena such as switching, hysteresis, as well as multistability can be observed in NEMS [13]. NEMS have been proposed as high sensitive position and mass sensors [14][15][16][17][18][19][20]. Recently, research at the nanoscale has focused not only on

• and NEMS. In this review, we analyze the adiabatic regime, realized when the internal vibrational modes have frequencies smaller than the hopping rate. Within this regime, one can observe phenomena such as switching, multistability and hysteresis in molecular junctions or NEMS, and study the physics

Rigid multipodal platforms for metal surfaces

• Michal Valášek,
• Marcin Lindner and
• Marcel Mayor

Beilstein J. Nanotechnol. 2016, 7, 374–405, doi:10.3762/bjnano.7.34

Hemolysin coregulated protein 1 as a molecular gluing unit for the assembly of nanoparticle hybrid structures

• Tuan Anh Pham,
• Andreas Schreiber,
• Elena V. Sturm (née Rosseeva),
• Stefan Schiller and
• Helmut Cölfen

Beilstein J. Nanotechnol. 2016, 7, 351–363, doi:10.3762/bjnano.7.32

• to a higher squareness value of the hysteresis curve. Thus the Hcp1_cys3 unit is shown to be very versatile in the formation of new biohybrid materials with enhanced magnetic, catalytic and optical properties. Keywords: gold catalyst; hemolysin coregulated protein 1 (Hcp1); magnetic hybrid materials

• magnetization (MS) of 12.81 emu/g, which is similar to the blank NPs of 13.21 emu/g. The hybrid material demonstrates at 2 K a similar hysteresis curve to the Fe3O4 NP with MS of 13.69 emu/g and remanent magnetization (MR) of 2.64 emu/g, but with a higher squareness value (MR/MS ratio) of 0.2 (Figure 10B). The

• from the analyses of the FFTs of HRTEM images of individual particles. The FFT retrieved from the whole chain is shown in the inset and is overlaid with the diffraction pattern of magnetite. A) and B) Hysteresis curves at 300 K and 2 K, respectively. C) ZFC curves of the fibers and pure NPs, which show

High-bandwidth multimode self-sensing in bimodal atomic force microscopy

• Michael G. Ruppert and
• S. O. Reza Moheimani

Beilstein J. Nanotechnol. 2016, 7, 284–295, doi:10.3762/bjnano.7.26

• amplitude branch as can be seen in Figure 9c and Figure 9g. It is worth noting that for this case, the fifth mode amplitudes obtained from the OBD sensor and from the charge sensor form a hysteresis loop and more significantly show inverse behavior for small separations (compare Figure 9d and Figure 9h). As

Influence of calcium on ceramide-1-phosphate monolayers

• Joana S. L. Oliveira,
• Gerald Brezesinski,
• Alexandra Hill and
• Arne Gericke

Beilstein J. Nanotechnol. 2016, 7, 236–245, doi:10.3762/bjnano.7.22

• monolayers in the condensed state are not perfectly reproducible concerning the areas per molecule (as already reported by Kooijman [8]). They exhibit hysteresis between compression and decompression, which proves the highly crystalline state of these systems and leads to limitations in a precise

Single-molecule magnet behavior in 2,2’-bipyrimidine-bridged dilanthanide complexes

• Wen Yu,
• Frank Schramm,
• Eufemio Moreno Pineda,
• Yanhua Lan,
• Olaf Fuhr,
• Jinjie Chen,
• Hironari Isshiki,
• Wolfgang Wernsdorfer,
• Wulf Wulfhekel and
• Mario Ruben

Beilstein J. Nanotechnol. 2016, 7, 126–137, doi:10.3762/bjnano.7.15

• with the presence of hysteresis loops. Keywords: bipyrimidine; diketone; hysteresis; lanthanide; magnetism; Introduction The application of magnetic molecular compounds within molecular electronic devices is combined in the progressive field of spintronics. An anisotropic spin is confined by the

• total spin, leading to slow magnetic relaxation and magnetic hysteresis at low temperatures. Combined with their long coherence times they could open the door to quantum computing [5][6]. After the first SMM was discovered in 1980 [7][8], for the next 15 years the SMM field was dominated by cluster

• was measured using AC, DC and micro-SQUID magnetometry techniques. The homo-dinuclear complexes of Dy(III) and Er(III) show single-molecule magnet behavior featuring hysteresis loops. The [Tb(tmhd)3]2bpm was sublimated on Au(111) surfaces and scanning tunneling microscopy results are presented in this

Controlled graphene oxide assembly on silver nanocube monolayers for SERS detection: dependence on nanocube packing procedure

• Martina Banchelli,
• Bruno Tiribilli,
• Roberto Pini,
• Luigi Dei,
• Paolo Matteini and
• Gabriella Caminati

Beilstein J. Nanotechnol. 2016, 7, 9–21, doi:10.3762/bjnano.7.2

• liquid–air interface followed by controlled transfer onto the surface of a solid substrate [24]. The LB procedure was already employed in a related paper [22] for the deposition of AgNCs onto solid substrates, here we extended the preparation protocol investigating in detail the influence of hysteresis

•  1, Figure S1) show a small hysteresis that vanishes completely after the second cycle. These findings exclude loss of material in the subphase upon compression and support the formation of elastic arrays of AgNCs that quickly recover their closely-packed morphology after expansion thanks to the

• ± 0.5 °C (Haake thermostatic bath, Germany). Continuous spreading isotherms and hysteresis cycles were obtained using the same barrier speed of 20 mm min−1 in both directions. The reported results are the average of at least three independent measurements. Langmuir–Blodgett films were transferred, after

An adapted Coffey model for studying susceptibility losses in interacting magnetic nanoparticles

• Mihaela Osaci and
• Matteo Cacciola

Beilstein J. Nanotechnol. 2015, 6, 2173–2182, doi:10.3762/bjnano.6.223

• . Consequently, multi-domain nanoparticles exhibit a lower hysteresis loss than single-domain nanoparticles [4]. For both theoretical and experimental researches in this field, choosing the right parameters of superparamagnetic nanoparticle systems to control magnetic hyperthermia is an important task [3][8][9

Selective porous gates made from colloidal silica nanoparticles

• Roberto Nisticò,
• Paola Avetta,
• Paola Calza,
• Debora Fabbri,
• Giuliana Magnacca and
• Dominique Scalarone

Beilstein J. Nanotechnol. 2015, 6, 2105–2112, doi:10.3762/bjnano.6.215

• materials (see inset in Figure 3A). The N2 gas-volumetric isotherm shown in Figure 3A is of the IV type, with a small hysteresis loop of H2 type (from IUPAC classification) in the relative pressure range 0.9–1, next to the condensation limit. The BET surface area is of ca. 260 m2 g−1 and the DFT pore size

Controlled switching of single-molecule junctions by mechanical motion of a phenyl ring

• Yuya Kitaguchi,
• Satoru Habuka,
• Hiroshi Okuyama,
• Shinichiro Hatta,
• Tetsuya Aruga,
• Thomas Frederiksen,
• Magnus Paulsson and
• Hiromu Ueba

Beilstein J. Nanotechnol. 2015, 6, 2088–2095, doi:10.3762/bjnano.6.213

• remarkable hysteresis appears when the molecule is successfully lifted and released. Note that Δz is defined as the distance toward the molecule with respect to the initial set point, as depicted in the inset. The current during the approach shows a jump at Δz = 2.6 Å to the high-current state, which returns

Nanostructured superhydrophobic films synthesized by electrodeposition of fluorinated polyindoles

• Gabriela Ramos Chagas,
• Thierry Darmanin and
• Frédéric Guittard

Beilstein J. Nanotechnol. 2015, 6, 2078–2087, doi:10.3762/bjnano.6.212

• properties, characterized by extremely high water contact angles (θw) and low water adhesion or hysteresis (also known as “Lotus effect”), grows exponentially because of the importance for both the scientific and industrial community [1][2][3][4][5][6]. Superhydrophobic properties are quite common in nature

• θwater for the C6F13-polyindoles can be seen in Figure 5. Indeed, not only θwater of 159.0° were measured on this polymer, but also highly oleophobic properties with θhexadecane = 93.3°. Moreover, the polymer presents extremely low hysteresis and sliding angles for normalized charges of 50 and 100 mC·cm

• Wenzel equation [36] (cos θ = r·cos θY, where r is a roughness parameter), the surface roughness can increase θ, but only if θY > 90°. Hence, it is possible to have an extremely high θwater, but the contact angle hysteresis (H) is usually high because the surface roughness increases also the solid–liquid

Two-phase equilibrium states in individual Cu–Ni nanoparticles: size, depletion and hysteresis effects

• Aram S. Shirinyan

Beilstein J. Nanotechnol. 2015, 6, 1811–1820, doi:10.3762/bjnano.6.185

• transformation of binary alloyed nanoparticles taking into account size effects as well as depletion and hysteresis effects. In such a way the hysteresis in a form of nonsymmetry for forth and back transforming paths takes place; compositional splitting and the loops-like splitted path on the size dependent

• the point for nanosolidus. Thus nanosolidus and nanoliquidus may be not interrelated. We call this difference between the end point of forth transition and starting point of back transition as ‘thermodynamic hysteresis’. Similar effect has been shown for a structural transition of Fe-nanoparticle

• ensemble subjected to temperature change [41]. The reason of such hysteresis is nonsymmetry of transforming path of a nanosystem with respect to the initial conditions leading to differences in two-phase loops of nanomelting and nanosolidification in presented case. For example, for Cu–Ni nanoparticle

A facile method for the preparation of bifunctional Mn:ZnS/ZnS/Fe₃O₄ magnetic and fluorescent nanocrystals

• Houcine Labiadh,
• Tahar Ben Chaabane,
• Romain Sibille,
• Lavinia Balan and
• Raphaël Schneider

Beilstein J. Nanotechnol. 2015, 6, 1743–1751, doi:10.3762/bjnano.6.178

• could be related to the quantum confinement effects of nanocrystals and to the diamagnetic contribution of the ZnS core. At 2 K, all bifunctional nanoparticles exhibited hysteresis with remnance magnetization, MR, at 9 T and coercivity, HC, indicating a dominant ferromagnetic nature of the iron oxide

• layer. The magnetic characteristics (MR, M9T, and HC) of the samples are given in Table 2. One can observe that the hysteresis loops are not saturated even for fields up to ±9 T; this could be due to frozen spins at the surface of the nanocrystals as reported in previous works [32][33]. The coercive

• fields increased with the iron oxide layer thickness, where the highest HC value of 0.18 T was measured for Mn:ZnS/ZnS/Fe3O4 QDs (3). Thus, the nanocrystals become magnetically harder with an increasingly open hysteresis loop with increasing thickness of the magnetite shell. The values of MR and M9T

Radiation losses in the microwave K_u band in magneto-electric nanocomposites

• Talwinder Kaur,
• Sachin Kumar,
• Jyoti Sharma and
• A. K. Srivastava

Beilstein J. Nanotechnol. 2015, 6, 1700–1707, doi:10.3762/bjnano.6.173

• interaction between the spins of hexaferrite and polyaniline are effecting the motion of π electrons, which causes an increase the absorption curve area [5][35]. Magnetic properties Hysteresis loops for PANI/Barium ferrite composites recorded at room temperature are shown in Figure 4. The magnetic parameters

• hexaferrite and (b) composite COP at room temperature in the X band. Hysteresis loops of composites. Transmission electron micrographs of magneto-electric composites (a) cluster of composites (b and c) particles of hexaferrite enclosed by polyaniline (CL6P). Reflection loss for composites. Real (µ′) and

Synthesis, characterization and in vitro biocompatibility study of Au/TMC/Fe₃O₄ nanocomposites as a promising, nontoxic system for biomedical applications

• Hanieh Shirazi,
• Maryam Daneshpour,
• Soheila Kashanian and
• Kobra Omidfar

Beilstein J. Nanotechnol. 2015, 6, 1677–1689, doi:10.3762/bjnano.6.170

• seemed that the magnetic nanoparticles were rather embedded in a chitosan matrix. According to the hysteresis curves (Figure 1c), the saturation magnetization (Ms) of TMC/Fe3O4 nanoparticles was 59.15 emu/g, which was notably higher than 33.65 emu/g found for the chitosan/Fe3O4 nanoparticles. Both of

• percentage of the viability of the control culture [48][54]. (a) TEM image of uncoated Fe3O4 nanoparticles and their (b) corresponding particle size distribution. (c) Hysteresis loop of the synthesized magnetic nanoparticles: (1) Fe3O4, (2) TMC/Fe3O4, (3) Au/TMC/Fe3O4, (4) chitosan/Fe3O4 and (5) Au/chitosan

Structural and magnetic properties of iron nanowires and iron nanoparticles fabricated through a reduction reaction

• Marcin Krajewski,
• Wei Syuan Lin,
• Hong Ming Lin,
• Katarzyna Brzozka,
• Sabina Lewinska,
• Natalia Nedelko,
• Anna Slawska-Waniewska,
• Jolanta Borysiuk and
• Dariusz Wasik

Beilstein J. Nanotechnol. 2015, 6, 1652–1660, doi:10.3762/bjnano.6.167

• exactly the same ‘histories’ and according to the results of structural studies, they have almost similar structures. Thus, presented results of magnetic measurements reflect the realistic behaviours of both nanostructures. Figure 6a and Figure 6b present the magnetization hysteresis of Fe NWs and Fe NPs

• application of the external magnetic field during the fabrication process. This indicates that during analysis of the hysteresis parameters it is also needed to consider the possible mechanisms of magnetization reversal besides the impact of simple anisotropy. According to the TEM measurements, the

• b) iron nanoparticles with regards to structural experimental results. a) Magnetization hysteresis loops of iron nanowires and nanoparticles at room temperature (Inset – magnification of hysteresis); b) Normalized magnetization hysteresis loops of both studied nanostructures; c) Magnetization as a