Uniform cobalt nanoparticles embedded in hexagonal mesoporous nanoplates as a magnetically separable, recyclable adsorbent

• Can Zhao,
• Yuexiao Song,
• Tianyu Xiang,
• Wenxiu Qu,
• Shuo Lou,
• Xiaohong Yin and
• Feng Xin

Beilstein J. Nanotechnol. 2018, 9, 1770–1781, doi:10.3762/bjnano.9.168

• dopamine hydrochloride concentrations of: (a) 2.0, (b) 2.5, (c) 1.0 and (d) 2.5 g/L. (B) A photograph illustrating the physical separation of the adsorbent material (NPLs-2.5-800) from water in the presence of an external magnetic field (permanent magnet). (A) Raman spectrum and (B–D) XPS spectra of the

Increasing the performance of a superconducting spin valve using a Heusler alloy

• Andrey A. Kamashev,
• Aidar A. Validov,
• Joachim Schumann,
• Vladislav Kataev,
• Bernd Büchner,
• Yakov V. Fominov and
• Ilgiz A. Garifullin

Beilstein J. Nanotechnol. 2018, 9, 1764–1769, doi:10.3762/bjnano.9.167

• magnetic field, should yield a complete switching on and off of the superconducting current in such a construction. A number of experimental studies have confirmed the predicted effect of the mutual orientation of magnetizations in the F1/S/F2 structure on Tc [5][6][7][8][9]. However, the major difficulty

• magnetic vectors. This is because in the former case the mean exchange field from the F-layers destructively acting on the Cooper pairs is larger. Thus, under favorable conditions the switching between AP and P configurations, which could be achieved by an appropriate application of a small external

Magnetic properties of Fe₃O₄ antidot arrays synthesized by AFIR: atomic layer deposition, focused ion beam and thermal reduction

• Juan L. Palma,
• Alejandro Pereira,
• Raquel Álvaro,
• José Miguel García-Martín and
• Juan Escrig

Beilstein J. Nanotechnol. 2018, 9, 1728–1734, doi:10.3762/bjnano.9.164

• lattice parameters are slightly larger than those of the arrays with smaller lattice parameters (i.e., the curves exhibit a wider and more vertical shape), regardless of whether we treat square or hexagonal arrays. Small differences exist between the loops obtained with the external magnetic field applied

• increases with increasing the lattice parameter of the array and by applying the magnetic field along the direction of the second-neighbor holes. This means that the coercivity increases with increasing space between the holes in the direction in which the external magnetic field is applied. Of course, this

• increases, a behavior opposite to that observed in arrays of antidots obtained from other synthesis techniques [30], which may be associated with the thermal reduction process of AFIR. Figure 6 shows the coercivity and normalized remanence as a function of the angle at which the external magnetic field is

Nanocomposites comprised of homogeneously dispersed magnetic iron-oxide nanoparticles and poly(methyl methacrylate)

• Sašo Gyergyek,
• David Pahovnik,
• Ema Žagar,
• Alenka Mertelj,
• Rok Kostanjšek,
• Miloš Beković,
• Marko Jagodič,
• Heinrich Hofmann and
• Darko Makovec

Beilstein J. Nanotechnol. 2018, 9, 1613–1622, doi:10.3762/bjnano.9.153

• coercivity in the absence of an external magnetic field [1][2]. Their colloidal suspensions are vital in a variety of technological [3] and biomedical applications [4], such as contrast agents in magnetic resonance imaging (MRI) [5][6], targeted drug delivery [6] and magnetic hyperthermia based on the

Robust topological phase in proximitized core–shell nanowires coupled to multiple superconductors

• Tudor D. Stanescu,
• Anna Sitek and
• Andrei Manolescu

Beilstein J. Nanotechnol. 2018, 9, 1512–1526, doi:10.3762/bjnano.9.142

• presence of the core [29]. The corresponding direction of the spin-orbit field for electrons moving along the wire is shown in Figure 1. The next term in Equation 1, ΓB = gμbB, corresponds to the Zeeman spin splitting generated by an external magnetic field applied parallel to the wire (e.g., along the z

Cr(VI) remediation from aqueous environment through modified-TiO₂-mediated photocatalytic reduction

• Rashmi Acharya,
• Brundabana Naik and
• Kulamani Parida

Beilstein J. Nanotechnol. 2018, 9, 1448–1470, doi:10.3762/bjnano.9.137

• overlap of the TiO2 band with that of Fe3O4 and (iii) efficient separation and recyclability of the catalyst under application of an external magnetic field because of the presence of magnetic Fe3O4. Therefore, the composite photocatalysts exhibited a higher rate of photoreduction of Cr(VI) as compared to

Andreev spectrum and supercurrents in nanowire-based SNS junctions containing Majorana bound states

• Jorge Cayao,
• Annica M. Black-Schaffer,
• Elsa Prada and
• Ramón Aguado

Beilstein J. Nanotechnol. 2018, 9, 1339–1357, doi:10.3762/bjnano.9.127

• is subjected to an external magnetic field (denoted by the black arrow). Superconducting correlations are induced into the nanowire via proximity effect, thus becoming superconducting with the induced pairing potential ΔS < ΔS′. Low-energy spectrum of a superconducting nanowire as function of the

• on top of two s-wave superconductors (S’) with pairing potentials ΔS′ and subjected to an external magnetic field (denoted by the black arrow). Superconducting correlations are induced into the nanowire through the proximity effect. Bottom: Left and right regions of the nanowire become

Magnetic characterization of cobalt nanowires and square nanorings fabricated by focused electron beam induced deposition

• Federico Venturi,
• Gian Carlo Gazzadi,
• Amir H. Tavabi,
• Alberto Rota,
• Rafal E. Dunin-Borkowski and
• Stefano Frabboni

Beilstein J. Nanotechnol. 2018, 9, 1040–1049, doi:10.3762/bjnano.9.97

• performed on as-deposited samples without applying an external magnetic field. Two different sets of NWs on amorphous C substrates were studied: one deposited at a beam energy of 15 keV and another deposited at a beam energy of 5 keV. In each sample, the deposited shape was the same: 2.5 µm in length, 50 nm

• this map, a slight accumulation of deposit at the corner is visible. However, it does not appear to affect the overall magnetic state. Before performing MFM, the same external magnetic field Bext of 0.3 T, aligned with one of the sides, was applied outside the microscope. After the first analysis, it

• content (by 5–10% for the 5 keV deposition than for the 15 keV deposition) and a difference in NW width. L-TEM analysis of both the NWs and the square rings provided insight into the effect on magnetic domain structure of a weak external magnetic field. L-TEM images of NWs were used to reveal the presence

Single-crystalline FeCo nanoparticle-filled carbon nanotubes: synthesis, structural characterization and magnetic properties

• Rasha Ghunaim,
• Maik Scholz,
• Christine Damm,
• Bernd Rellinghaus,
• Rüdiger Klingeler,
• Bernd Büchner,
• Michael Mertig and
• Silke Hampel

Beilstein J. Nanotechnol. 2018, 9, 1024–1034, doi:10.3762/bjnano.9.95

• ) were heated to a temperature of 900 °C with a heating rate of 5 K/min followed by an isothermal of 15 min under air atmosphere with a flow rate of 100 mL/min. The magnetic field dependence of the magnetization at 5 K and 300 K in an external magnetic field up to ±5 T was measured by means of

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

• Danil A. Petrov Pavel K. Skokov Alexander N. Zakhlevnykh Physics of Phase Transitions Department, Perm State University, Bukireva St. 15, 614990 Perm, Russia 10.3762/bjnano.8.280 Abstract We propose a continuum theory of orientational phase transitions induced by an external magnetic field in a

• coupling () of CNTs to the LC matrix. In this state, the directors of the LC and CNTs are directed orthogonally to the external magnetic field and parallel to the boundaries of the layer. Another uniform solution [φ(ζ) = 0 and ψ(ζ) = π/2] corresponds to the homeotropic phase where the LC director is

• matrix there is an analogous response of the LC director and magnetization to the external magnetic field, and the sequence of transitions is: uniform compensated phase (planar phase) – non-uniform phase. There are some very important differences between compensated ferronematics and the suspension of

Beyond Moore’s technologies: operation principles of a superconductor alternative

• Igor I. Soloviev,
• Nikolay V. Klenov,
• Sergey V. Bakurskiy,
• Mikhail Yu. Kupriyanov,
• Alexander L. Gudkov and
• Anatoli S. Sidorenko

Beilstein J. Nanotechnol. 2017, 8, 2689–2710, doi:10.3762/bjnano.8.269

Ferrocholesteric–ferronematic transitions induced by shear flow and magnetic field

• Dmitriy V. Makarov,
• Alexander A. Novikov and
• Alexander N. Zakhlevnykh

Beilstein J. Nanotechnol. 2017, 8, 2552–2561, doi:10.3762/bjnano.8.255

• mechanism of interaction between the LC and an external magnetic field, the addition of magnetic particles into the LC leads to the appearance of an additional dipole mechanism of the influence on the system. Some types of synthesized ferroliquid crystals have ferromagnetic properties and are highly

• sensitive to an external magnetic field [11][12]. If the carrier medium in the ferroliquid crystal is a cholesteric liquid crystal (CLC), such a composite system is called ferrocholesteric (FC). A distinctive feature of a CLC is the presence of a supramolecular helical structure, which is very sensitive to

• structure with λ < 1. In Figure 3 we see that as λ decreases, the critical value of uc decreases and weakly depends on the orientation of the external magnetic field. Figure 4 and Figure 5 represent the diagrams of the ferrocholesteric–ferronematic phase transition in the plane u–h for the magnetic field

Alternating current magnetic susceptibility of a ferronematic

• Natália Tomašovičová,
• Jozef Kováč,
• Veronika Gdovinová,
• Nándor Éber,
• Tibor Tóth-Katona,
• Jan Jadżyn and
• Peter Kopčanský

Beilstein J. Nanotechnol. 2017, 8, 2515–2520, doi:10.3762/bjnano.8.251

• properties, such as the capability of these materials to respond to external magnetic field more efficiently, comes from the collective properties of the MNPs dispersed in the liquid crystal. In this respect, investigation of such colloidal LC systems opens up new perspectives even for applications. While

Dynamic behavior of a nematic liquid crystal mixed with CoFe₂O₄ ferromagnetic nanoparticles in a magnetic field

• Emil Petrescu,
• Cristina Cirtoaje and
• Cristina Stan

Beilstein J. Nanotechnol. 2017, 8, 2467–2473, doi:10.3762/bjnano.8.246

• magnetic field to reorient the LC molecules and faster decrease the transition threshold. A mixture of 1% CoFe2O4 and the nematic 4-cyano-4′-pentylbiphenyl (5CB, Aldrich) was used in a 180 micrometer thick planar cell subjected to an external magnetic field. Due to their magnetic properties, the

The interplay between spin densities and magnetic superexchange interactions: case studies of mono- and trinuclear bis(oxamato)-type complexes

• Azar Aliabadi,
• Bernd Büchner,
• Vladislav Kataev and
• Tobias Rüffer

Beilstein J. Nanotechnol. 2017, 8, 2245–2256, doi:10.3762/bjnano.8.224

• term represents the Zeeman interaction of an electron spin S with an external magnetic field B0, while g and μB stand for the g-tensor and the Bohr magneton, respectively. The hyperfine (HF) interaction between the electron spin S of Cu(II) and the 63Cu, 65Cu and 14N nuclear spins ICu and IN is

• described by the second and the third term, respectively. Here, ACu and AN are the on-site Cu and transferred N HF coupling tensors, respectively. The last term describes the nuclear Zeeman interaction of the 63Cu, 65Cu and 14N nuclear spins ICu and IN with the external magnetic field B0, which is not

• ENDOR spectra of 8@7 at (ν = 9.56 GHz, T = 20 K) at six different orientations of the single crystal in the external magnetic field. The 0° orientation corresponds to the direction of B0 along the -axis of the g-tensor, and the 90° orientation represents the perpendicular direction. Reproduced with

(Metallo)porphyrins for potential materials science applications

• Lars Smykalla,
• Carola Mende,
• Michael Fronk,
• Pablo F. Siles,
• Michael Hietschold,
• Georgeta Salvan,
• Dietrich R. T. Zahn,
• Oliver G. Schmidt,
• Tobias Rüffer and
• Heinrich Lang

Beilstein J. Nanotechnol. 2017, 8, 1786–1800, doi:10.3762/bjnano.8.180

• addition to what is easily readable in the UV–vis spectra [14]. The reason for the fine structure of the MCD spectra and hence for the higher sensitivity to the electronic properties lies in the Zeeman splitting of degenerate electronic levels induced by an external magnetic field. In addition to the

Synthesis and catalytic application of magnetic Co–Cu nanowires

• Lijuan Sun,
• Xiaoyu Li,
• Zhiqiang Xu,
• Kenan Xie and
• Li Liao

Beilstein J. Nanotechnol. 2017, 8, 1769–1773, doi:10.3762/bjnano.8.178

• replacement under an external magnetic field. The characterization results confirmed that the as-prepared product was bimetallic Co–Cu nanowires with a desirable linear structure. Additionally, the magnetic hysteresis loop showed that the bimetallic Co–Cu nanowires were paramagnetic, which meant they could be

• difference between the Co–Cu nanowire synthesis with and without application of an external magnetic field. It was very evident that the linear structure of the Co–Cu nanowires prepared without an external magnetic field was undesirable. Moreover, the Co–Cu nanowires prepared without an external magnetic

• emu·g−1, respectively. The appearance of a hysteresis loop demonstrated that the bimetallic Co–Cu nanowires possessed paramagnetism [12]. Therefore, the bimetallic Co–Cu nanowires could be easily separated from the solution by providing an external magnetic field. Figure 5b shows the plots of evolution

Near-infrared-responsive, superparamagnetic Au@Co nanochains

• Varadee Vittur,
• Arati G. Kolhatkar,
• Shreya Shah,
• Irene Rusakova,
• Dmitri Litvinov and
• T. Randall Lee

Beilstein J. Nanotechnol. 2017, 8, 1680–1687, doi:10.3762/bjnano.8.168

• (superparamagnetism) and provide a potentially useful new nanoarchitecture for biomedical or catalytic applications that can benefit from both activation by light and manipulation using an external magnetic field. Keywords: Au@Co; magneto-optical; nanochains; near-IR-active; superparamagnetic; Introduction The

• external magnetic field. Furthermore, the NIR-responsive capability (optical extinction maximum at ca. 900 nm) combined with their magnetic properties can plausibly be harnessed in nanotechnology-based biomedical applications, such as photo-thermally modulated drug delivery, photonic devices, and photo

• nanospheres in contrast to the chain-linked structures obtained using a magnetic stirrer. This control experiment indicates a likely interaction between the magnetic nanoparticles and the external magnetic field produced by the magnetic stirrer during the galvanic replacement reaction. We hypothesize that

Light-induced magnetoresistance in solution-processed planar hybrid devices measured under ambient conditions

• Sreetama Banerjee,
• Daniel Bülz,
• Danny Reuter,
• Karla Hiller,
• Dietrich R. T. Zahn and
• Georgeta Salvan

Beilstein J. Nanotechnol. 2017, 8, 1502–1507, doi:10.3762/bjnano.8.150

• ) designed and developed in this work. Negative magnetoresistance (positive magnetoconductance) was observed for both types of devices similar to the observations in [9]. Magnetoresistance is defined as the change in resistivity of a material/device due to application of an external magnetic field

• . Magnetoconductance (MC) is the change in conductivity of a material/device upon application of an external magnetic field. The magnetoresistance effect, however, was found to degrade over time significantly faster than the photocurrent. We suggest that this degradation is due to incorporation of water molecules from

Spin-chemistry concepts for spintronics scientists

• Konstantin L. Ivanov,
• Alexander Wagenpfahl,
• Carsten Deibel and
• Jörg Matysik

Beilstein J. Nanotechnol. 2017, 8, 1427–1445, doi:10.3762/bjnano.8.143

• a factor of three. In real cases, a quantum mechanical treatment should be used to calculate the conversion efficiency as a function of the external magnetic field strength. Thus, we obtain that the interconversion efficiency is sensitive to external magnetic fields, giving rise to MFEs on chemical

• experiment. For observing MFEs in steady-state experiments, it is necessary to have some “branching”, which makes the overall product yield dependent on the interconversion rate, i.e., on the external magnetic field strength. In the absence of such branching, all radical pairs would eventually recombine

• all field directions in space become completely equivalent. However, in solids the reaction yield and the MFE can depend on the direction of the external magnetic field [91][92][93]. RYDMR One more important member of the family of spin-chemistry techniques is RYDMR [94][95][96][97]. The idea of RYDMR

Characterization of ferrite nanoparticles for preparation of biocomposites

• Urszula Klekotka,
• Magdalena Rogowska,
• Dariusz Satuła and
• Beata Kalska-Szostko

Beilstein J. Nanotechnol. 2017, 8, 1257–1265, doi:10.3762/bjnano.8.127

• , interaction with living cells can be obtained. The use of an external magnetic field quite often helps in removing toxins from healthy cells [13][14] via modified nanoparticles having a sieve-like property. The main aim of this work is to study immobilization effects of biological particles to the selected

• external magnetic field while the size of the particles is a critical parameter. It was observed that superparamagnetic fluctuations are blocked (or not blocked) at RT for nanoparticles with a diameter smaller than the reference magnetite due to elemental substitution. Therefore, at any stage of the

Ultrasmall magnetic field-effect and sign reversal in transistors based on donor/acceptor systems

• Thomas Reichert and
• Tobat P. I. Saragi

Beilstein J. Nanotechnol. 2017, 8, 1104–1114, doi:10.3762/bjnano.8.112

• , which favours the formation of bipolarons. The formation process is spin-sensitive and the number of bipolarons is reduced for an increasing external magnetic field. At low drain voltage, a moderate number of bipolaron species is present and positive magnetoresistance is obtained. For larger Vd values

Tuning the spin coherence time of Cu(II)−(bis)oxamato and Cu(II)−(bis)oxamidato complexes by advanced ESR pulse protocols

• Ruslan Zaripov,
• Evgeniya Vavilova,
• Iskander Khairuzhdinov,
• Kev Salikhov,
• Violeta Voronkova,
• Mohammad A. Abdulmalic,
• Francois E. Meva,
• Saddam Weheabby,
• Tobias Rüffer,
• Bernd Büchner and
• Vladislav Kataev

Beilstein J. Nanotechnol. 2017, 8, 943–955, doi:10.3762/bjnano.8.96

• in fused quartz has been made. The shift of the ESR resonance frequency can be written in the form Δω = ∑AkMk, where Ak and Mk are the HF constant and the projection of the k-th nuclear spin on the direction of the external magnetic field. For a number of reasons the projection Mk can stochastically

Synthesis of graphene–transition metal oxide hybrid nanoparticles and their application in various fields

• Arpita Jana,
• Elke Scheer and
• Sebastian Polarz

Beilstein J. Nanotechnol. 2017, 8, 688–714, doi:10.3762/bjnano.8.74

Intercalation and structural aspects of macroRAFT agents into MgAl layered double hydroxides

• Dessislava Kostadinova,
• Ana Cenacchi Pereira,
• Muriel Lansalot,
• Franck D’Agosto,
• Elodie Bourgeat-Lami,
• Fabrice Leroux,
• Christine Taviot-Guého,
• Sylvian Cadars and
• Vanessa Prevot

Beilstein J. Nanotechnol. 2016, 7, 2000–2012, doi:10.3762/bjnano.7.191

• ., almost exclusively those of the LDH hydroxyl groups. In a last step, the obtained 1H magnetization is stored parallel to the external magnetic field axis for a time τM to allow this magnetization to diffuse among abundant 1H nuclei within both the LDH host and the (co)polymer guest. This process occurs