Preparation of Ni/Cu composite nanowires

• Hu Wang,
• Xiaoyu Li,
• Ming Li,
• Kenan Xie and
• Li Liao

Beilstein J. Nanotechnol. 2015, 6, 1268–1271, doi:10.3762/bjnano.6.130

• surface of nickel nanowires, named Ni/Cu composite nanowires, was developed for the first time. The synthetic process consisted of two steps. Firstly, pure nickel nanowires were prepared in solution without template by applying a weak external magnetic field. Secondly, the obtained nickel nanowires were

• (a) and Ni/Cu composite nanowires (b). It can be observed from Figure 3a that nickel particles are assembled into a solid linear structure under an external magnetic field, which correspond with our previous research [7][20]. It is obvious that the surface of the Ni/Cu composite nanowires is compact

• self-assembly of nickel particles under an external magnetic field and the reduction of Cu2+ on the surface of prepared nickel nanowires. It is found that an external magnetic field can make nickel particles self-assemble in one dimension, leading to the formation of polycrystalline nickel nanowires

Magnetic properties of iron cluster/chromium matrix nanocomposites

• Arne Fischer,
• Robert Kruk,
• Di Wang and
• Horst Hahn

Beilstein J. Nanotechnol. 2015, 6, 1158–1163, doi:10.3762/bjnano.6.117

• -field cooled/field cooled (ZFC/FC) magnetization measurements and magnetic hysteresis loops recorded in a commercial superconducting quantum interference device (SQUID, Quantum Design) magnetometer. The ZFC/FC curves were collected with an applied external magnetic field of μ0H = 20 mT in a temperature

• range between 10 and 350 K. The measurement geometry was in-plane, i.e., the external magnetic field was applied parallel to the sample surface (as for all magnetic data presented in this paper). Figure 2 shows the TB of the Fex/Cr samples extracted from the ZFC/FC curves. At this point it is reasonable

• interactions) become dominant. Hysteresis loops were recorded at 5 K after field cooling from 350 K, which is above the TN of Cr (311 K [16]), in an external magnetic field of μ0H = 4.5 T. A linear diamagnetic background originating from the Si substrate as well as the Au layers was subtracted. The coercivity

Interaction of electromagnetic radiation in the 20–200 GHz frequency range with arrays of carbon nanotubes with ferromagnetic nanoparticles

• Agylych Atdayev,
• Alexander L. Danilyuk and
• Serghej L. Prischepa

Beilstein J. Nanotechnol. 2015, 6, 1056–1064, doi:10.3762/bjnano.6.106

• material are currently the subject of intensive study. The properties of such materials can be tuned by the external magnetic field, spin-polarized current or electromagnetic radiation. In conventional ferromagnetic materials, the magnetic properties are determined by the domain structure and domain walls

Production, detection, storage and release of spin currents

• Michele Cini

Beilstein J. Nanotechnol. 2015, 6, 736–743, doi:10.3762/bjnano.6.75

• vertices of the polygon represent sites and are acted upon by the spin–orbit interaction and by the external magnetic field B(t). The side length may be taken to be of order of a few angstroms. All sites are connected to the first neighbors by spin-diagonal matrix elements. The Hamiltonian for the left and

Manipulation of magnetic vortex parameters in disk-on-disk nanostructures with various geometry

• Maxim E. Stebliy,
• Alexander G. Kolesnikov,
• Alexey V. Ognev,
• Alexander S. Samardak and
• Ludmila A. Chebotkevich

Beilstein J. Nanotechnol. 2015, 6, 697–703, doi:10.3762/bjnano.6.70

• sandwich consisting of two permalloy (Py) disks with diameters of 600 and 200 nm separated by a nonmagnetic interlayer are studied. Magnetization reversal of the disk-on-disk nanostructures depends on the distance between centers of the small and big disks and on orientation of an external magnetic field

• different combinations of polarity and chirality [2]. Polarity (up or down out-of-plane component of magnetization in the central core of the vortex state) can be controlled by an external magnetic field aligned perpendicular to a disk plane. This method is complicated to be used for microelectronic

• nanostructures with different distances between its centers, s, which range from 0 (small disk in the center) to 230 nm (small disk at the edge of big disk). We have experimentally studied the effect of the orientation of the disk-on-disk nanostructure relatively to an external magnetic field on the

Silica micro/nanospheres for theranostics: from bimodal MRI and fluorescent imaging probes to cancer therapy

• Shanka Walia and
• Amitabha Acharya

Beilstein J. Nanotechnol. 2015, 6, 546–558, doi:10.3762/bjnano.6.57

• magnetic field. It was observed that the bifunctional NPs were distributed uniformly in the solution as long as there was an external magnetic field. The detection limit of tripropylamine (TPA) with these sensors was found to be 6.5 nM. Similarly, Santra et al. [28] reported the synthesis of

• superparamagnetic behavior for both iron oxide and the bifunctional nanocomposite with saturation magnetization values of 68.8 and 9.7 emu/g, respectively. To study the application of these NPs in an electrochemiluminescence sensor, these NPs were fabricated on a glassy carbon wafer in the presence of an external

Multifunctional layered magnetic composites

• Maria Siglreitmeier,
• Baohu Wu,
• Tina Kollmann,
• Martin Neubauer,
• Gergely Nagy,
• Dietmar Schwahn,
• Vitaliy Pipich,
• Damien Faivre,
• Dirk Zahn,
• Andreas Fery and
• Helmut Cölfen

Beilstein J. Nanotechnol. 2015, 6, 134–148, doi:10.3762/bjnano.6.13

• sample at 2 K and 293 K. Inset: Enlargement of the low-field region showing the different coercive fields for the NPs at 2 and 293 K. Attraction of modified nacre with b) no magnetic field and c) external magnetic field (ca. 1 Tesla). Degree of sample swelling plotted as a function of the swelling time

Synthesis of boron nitride nanotubes and their applications

• Saban Kalay,
• Zehra Yilmaz,
• Ozlem Sen,
• Melis Emanet,
• Emine Kazanc and
• Mustafa Çulha

Beilstein J. Nanotechnol. 2015, 6, 84–102, doi:10.3762/bjnano.6.9

• the external magnetic field. A superconducting quantum interference device (SQUID) magnetometer analysis was carried out and revealed that the magnetic properties of the BNNTs were related to the Fe catalysts. Considering the magnetic properties and the ability to bind molecules on a large surface

• –NaGdF4:Eu composites had higher toxicity in the presence of a magnetic field due to increased cellular uptake of the composites and thus increased doxorubicin delivery. It can be said that the BNNT–NaGdF4:Eu composites increase the chemotherapy efficiency by the use of an external magnetic field [84

Experimental techniques for the characterization of carbon nanoparticles – a brief overview

• Wojciech Kempiński,
• Szymon Łoś,
• Mateusz Kempiński and
• Damian Markowski

Beilstein J. Nanotechnol. 2014, 5, 1760–1766, doi:10.3762/bjnano.5.186

• [8]. The localization of charge carriers can be easily observed with the EPR technique [36]. This consists of the resonant absorption of microwave energy by unpaired spins (localized charge carriers) placed in the external magnetic field. The EPR signal of ACFs can be observed only in the low

Physics, chemistry and biology of functional nanostructures II

• Anatolie S. Sidorenko

Beilstein J. Nanotechnol. 2014, 5, 1218–1219, doi:10.3762/bjnano.5.134

• current of up to 107 A/cm2. However, this critical current is only present in the MgB2 superconducting material when there is no magnetic field. The external magnetic field very rapidly suppresses the critical current and destroys the superconductivity of magnesium diboride. This issue was successfully

Designing magnetic superlattices that are composed of single domain nanomagnets

• Derek M. Forrester,
• Feodor V. Kusmartsev and
• Endre Kovács

Beilstein J. Nanotechnol. 2014, 5, 956–963, doi:10.3762/bjnano.5.109

• applied magnetic field Throughout we use the damping parameter equal to α = 0.01 and a large value of b (about 390) to confine the magnetic moments to move in the x–y-plane. We investigated nanomagnets with semi-major to semi-minor elliptical cross-sections of lx/ly ≈ 10. The external magnetic field in

• parameter a is shown through the phase diagram of Figure 1a for the two coupled nanomagnets systems that were also considered in [15]. In this phase diagram the AF1 phase occurs when [15] In this system the average magnetization, that evolves with the application of an external magnetic field, has a

Manipulation of isolated brain nerve terminals by an external magnetic field using D-mannose-coated γ-Fe₂O₃ nano-sized particles and assessment of their effects on glutamate transport

• Tatiana Borisova,
• Natalia Krisanova,
• Arsenii Borуsov,
• Roman Sivko,
• Ludmila Ostapchenko,
• Michal Babic and
• Daniel Horak

Beilstein J. Nanotechnol. 2014, 5, 778–788, doi:10.3762/bjnano.5.90

• of Kyiv, 64 Volodymyrska Str, Kiev, Ukraine The Department of Polymer Particles, Institute of Macromolecular Chemistry AS CR, Heyrovsky Sq. 2, 162 06 Prague 6, Czech Republic 10.3762/bjnano.5.90 Abstract The manipulation of brain nerve terminals by an external magnetic field promises breakthroughs

• . The study also focused on the analysis of the potential use of these nanoparticles for manipulation of nerve terminals by an external magnetic field. It was shown that more than 84.3 ± 5.0% of L-[14C]glutamate-loaded synaptosomes (1 mg of protein/mL) incubated for 5 min with D-mannose-coated γ-Fe2O3

• uptake and release; manipulation by an external magnetic field; D-mannose; membrane potential; nanoparticles; rat brain nerve terminals; synaptic vesicle acidification; Introduction Nanoparticles have great biotechnological potential opening a wide range of new applications. Properties of nanomaterials

Spin relaxation in antiferromagnetic Fe–Fe dimers slowed down by anisotropic Dy^III ions

• Valeriu Mereacre,
• Frederik Klöwer,
• Yanhua Lan,
• Rodolphe Clérac,
• Juliusz A. Wolny,
• Volker Schünemann,
• Christopher E. Anson and
• Annie K. Powell

Beilstein J. Nanotechnol. 2013, 4, 807–814, doi:10.3762/bjnano.4.92

• with the iron centres [14][15]. Moreover, the reported compounds [14][15] – with an antiferromagnetic coupling in the central iron dimer – show a very intriguing effect: the collapse of the magnetic hyperfine splitting under the effect of the external magnetic field. This apparently paradoxical

• structural aspect can prevail over the others. Here, we report how, contrary to reported Fe2Dy2 compounds [14][15], the application of an external magnetic field does not always affect the ground state of the DyIII ion and its relaxation time. Two compounds [Fe4Ln2(μ3-OH)2(L)4((CH3)3CCOO)6(N3)2]·(solv) (Ln

• through a free iteration method with two sextets with the effective hyperfine fields Beff = 23.5 and 23.2 T, respectively, at the nuclei. When applying an external magnetic field one cannot see significant changes in the values of the hyperfine parameters. The spectra represent a superposition of two

Nanoglasses: a new kind of noncrystalline materials

• Herbert Gleiter

Beilstein J. Nanotechnol. 2013, 4, 517–533, doi:10.3762/bjnano.4.61

• FeSc nanoglasses Figure 16 presents the magnetization curves, M (magnetization) versus H (external magnetic field), of a nanoglass sample and of a melt-spun ribbon having the same chemical composition (Fe90Sc10) [17]. The M-versus-H loop, recorded at ambient temperature, evidences that the ribbon is

• ). Magnetization curves (magnetization versus external magnetic field) of a nanoglass sample (red) and a melt-spun ribbon (green) at 300 K. The ribbon exhibits paramagnetic behavior, while the nanoglass shows a curve characteristic for ferromagnetic materials with a magnetization of 1 μB per Fe atom in the applied

Ferromagnetic behaviour of Fe-doped ZnO nanograined films

• Boris B. Straumal,
• Svetlana G. Protasova,
• Andrei A. Mazilkin,
• Thomas Tietze,
• Eberhard Goering,
• Gisela Schütz,
• Petr B. Straumal and
• Brigitte Baretzky

Beilstein J. Nanotechnol. 2013, 4, 361–369, doi:10.3762/bjnano.4.42

• widely debated since 2000. In their theoretical work, Dietl et al. discussed the chances for oxides to possess saturation of magnetisation in an external magnetic field, coercivity, and a Curie temperature above room temperature (RT) [1]. According to their theory, FM could appear if one dopes the oxides

Antiferromagnetic coupling of TbPc₂ molecules to ultrathin Ni and Co films

• David Klar,
• Svetlana Klyatskaya,
• Andrea Candini,
• Bernhard Krumme,
• Kurt Kummer,
• Philippe Ohresser,
• Valdis Corradini,
• Valentina de Renzi,
• Roberto Biagi,
• Loic Joly,
• Jean-Paul Kappler,
• Umberto del Pennino,
• Marco Affronte,
• Heiko Wende and
• Mario Ruben

Beilstein J. Nanotechnol. 2013, 4, 320–324, doi:10.3762/bjnano.4.36

• visible. While the magnetic moments of Tb align parallel to the external magnetic field when the field is strong enough, they align antiparallel in a small magnetic field. This antiparallel alignment is caused by the magnetic coupling to the Ni substrate. At the top of Figure 3 one is able to identify the

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

• equal to the ones obtained for the as-grown C–Ni nanowires before annealing (Table 1 and Supporting Information File 1, Figure S3). The smaller saturation field ( = 1500 Oe) and the larger squareness (Mr/Ms = 0.4) when the external magnetic field is applied parallel to the nanowire axis, compared to the

• from the shape anisotropy resulting from the very high aspect ratio of these nanostructures [7][35][36][37][38][39][40][41][42][43]. Concerning the coercive field, it is slightly higher ( = 32 Oe) when the external magnetic field is applied parallel to the nanowire array, than the one measured for the

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

• ferromagnetic at room temperature down to a Co concentration of about 15 atom % [34]. MOKE remanence curves were measured by saturating the sample, subsequently applying a reverse field and recording the remanent magnetization (Figure 9). The angle θ of the external magnetic field with respect to the sample

Effect of spherical Au nanoparticles on nanofriction and wear reduction in dry and liquid environments

• Dave Maharaj and
• Bharat Bhushan

Beilstein J. Nanotechnol. 2012, 3, 759–772, doi:10.3762/bjnano.3.85

• treatment, nanoparticles are either functionalized with biomolecules that recognize and attach to the cancer cells, [6][7] or in the case of iron-oxide nanoparticles, the nanoparticles are directed by an external magnetic field [9]. The cells are destroyed by drugs that coat the nanoparticles or by

• absorbs the oil by motion of the nanoparticles towards the oil in a magnetic field [12]. Magnetic nanoparticles are also of interest in enhanced oil recovery (EOR) since they can be dispersed in fluid and manipulated and monitored by an external magnetic field [13][14]. In both oil detection and EOR

Analysis of fluid flow around a beating artificial cilium

• Mojca Vilfan,
• Gašper Kokot,
• Andrej Vilfan,
• Natan Osterman,
• Blaž Kavčič,
• Igor Poberaj and
• Dušan Babič

Beilstein J. Nanotechnol. 2012, 3, 163–171, doi:10.3762/bjnano.3.16

• superparamagnetic particles and driven along a tilted cone by a varying external magnetic field. Nonmagnetic tracer particles were used for monitoring the fluid flow generated by the cilium. The average flow velocity in the pumping direction was obtained as a function of different parameters, such as the rotation

• artificial cilia driven by an external magnetic field and proved that their asymmetric beating generated a directed fluid flow [8][9]. The artificial cilia were formed as stable yet flexible chains of superparamagnetic colloidal particles and were driven along a tilted inverted cone (Figure 1). An array of

• force between the chain and the anchoring site, and the actuation of the cilium were established with an external magnetic field. The optical tweezers were therefore equipped with a magnetic component that could generate a homogeneous magnetic field at the sample (Figure 5). Three orthogonal pairs of

Enhancement of the critical current density in FeO-coated MgB₂ thin films at high magnetic fields

• Andrei E. Surdu,
• Hussein H. Hamdeh,
• Imad A. Al-Omari,
• David J. Sellmyer,
• Alexei V. Socrovisciuc,
• Andrei A. Prepelita,
• Ezgi T. Koparan,
• Ekrem Yanmaz,
• Valery V. Ryazanov,
• Horst Hahn and
• Anatolie S. Sidorenko

Beilstein J. Nanotechnol. 2011, 2, 809–813, doi:10.3762/bjnano.2.89

• superconducting parameter makes it a very attractive candidate to replace Nb in various superconducting devices, namely for devices operating at temperatures around 20 K, which are attainable in low-cost cryocoolers. However, the dramatic fall of the critical current in an external magnetic field at temperatures

• around 20 K limits the possible use of magnesium diboride in engineering applications. Therefore, for a wide-scale technical application of MgB2 it is necessary to solve the problem of the enhancement of its critical current in an external magnetic field. Results and Discussion There have been many

• attempts to solve the above-mentioned problem relating to the decay of the critical current in an external magnetic field. Various research teams have tried to increase the critical current density either by doping MgB2 with various substances (carbon [3], aluminium [4], etc.) or by adding nanoparticles of

Distinguishing magnetic and electrostatic interactions by a Kelvin probe force microscopy–magnetic force microscopy combination

• Miriam Jaafar,
• Oscar Iglesias-Freire,
• Luis Serrano-Ramón,
• Manuel Ricardo Ibarra,
• Jose Maria de Teresa and
• Agustina Asenjo

Beilstein J. Nanotechnol. 2011, 2, 552–560, doi:10.3762/bjnano.2.59

• of the magnetic character of the sample. In addition, by means of variable field MFM [19], the changes in the signal as a function of the external magnetic field can be utilized either to evaluate the coercivity of the MFM probes [20][21] or to analyze the magnetic behavior of micro- and

• nanostructures [22][23], depending on the values of both the tip and sample coercive fields (Htip and Hsample) and the maximum external magnetic field applied (Hmax). Notice that the MFM measurements under an external magnetic field allow us to state the origin of the interaction but cannot remove other

Structural and magnetic properties of ternary Fe_1–xMn_xPt nanoalloys from first principles

• Markus E. Gruner and
• Peter Entel

Beilstein J. Nanotechnol. 2011, 2, 162–172, doi:10.3762/bjnano.2.20

• properties in a close interval of composition and energy gives rise to the hope that this material may allow the selection of specific magnetic or structural modifications with a fairly small energetic effort, which could be provided by an external magnetic field. In this respect, it looks promising that the

• their slope and different magnetic structures become competitive in energy. If composition and degree of order are carefully tuned, it might be possible to select the ferro or ferrimagnetic phase by an external magnetic field, while the ground state is still AF. In fact, Menshikov et al. [73

• ] demonstrated in their experiments, that an external magnetic field can induce a magnetization at finite temperatures in the vicinity of the Néel temperature, which decays again towards high as well as towards low temperatures. The authors explain this fact with the presence of FM clusters with possible

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

• electron yield at each photon energy and by switching the Ni film magnetization with a short external magnetic field pulse at each data point (a current of ≈100 A through two coils, 180 windings, magnetic field ≈1700 G). The photon helicity was kept fixed. Note that the nanoparticle data in Figure 2b are

Magnetic interactions between nanoparticles

• Steen Mørup,
• Mikkel Fougt Hansen and
• Cathrine Frandsen

Beilstein J. Nanotechnol. 2010, 1, 182–190, doi:10.3762/bjnano.1.22

• tendency for magnetic nanoparticles to form chains, especially if they can move freely in an external magnetic field, for example, if they are suspended in a liquid. If the nanoparticles form chains, a ferromagnetic ordering of the magnetic moments is favored in zero applied field with the magnetization