Wet-spinning of magneto-responsive helical chitosan microfibers

• Dorothea Brüggemann,
• Johanna Michel,
• Naiana Suter,
• Matheus Grande de Aguiar and
• Michael Maas

Beilstein J. Nanotechnol. 2020, 11, 991–999, doi:10.3762/bjnano.11.83

• . This strategy is based on wet-spinning of magnetic fibers, which are collected on a rotating needle controlled by an external magnetic field with a predefined helical geometry. The fibers were characterized regarding their morphology, microstructure, magnetization and mechanical characteristics. These

Effect of magnetic field, heat generation and absorption on nanofluid flow over a nonlinear stretching sheet

• Santoshi Misra and
• Govardhan Kamatam

Beilstein J. Nanotechnol. 2020, 11, 976–990, doi:10.3762/bjnano.11.82

• . The external magnetic field has a massive effect on the velocity profile of an electrically conducting fluid, which causes a considerable amount of resistance to its motion and a driving force, called the Lorentz force, which reduces the fluid velocity (Figure 12). Impact of M on θ(η) With an increase

• in the magnetic parameter, M, and, consequently, of the fluid resistance, the fluid temperature profile, θ(η), increases and so does the thickness of the thermal boundary layer. This is due to the fact that with an external magnetic field being employed, the temperature of the fluid increases

• distribution, ϕ(η), which is depicted in Figure 14. Even though there is a minimal increasing trend observed, the flow seems invariable. Since the concentration gradient of the fluid flow is not significantly modified by the external magnetic field applied, there is not much of a change in particle motion upon

Multilayer capsules made of weak polyelectrolytes: a review on the preparation, functionalization and applications in drug delivery

• Varsha Sharma and
• Anandhakumar Sundaramurthy

Beilstein J. Nanotechnol. 2020, 11, 508–532, doi:10.3762/bjnano.11.41

Nonequilibrium Kondo effect in a graphene-coupled quantum dot in the presence of a magnetic field

• Levente Máthé and
• Ioan Grosu

Beilstein J. Nanotechnol. 2020, 11, 225–239, doi:10.3762/bjnano.11.17

• Equation 1, HD, models the interacting QD and reads: where εdσ is the discrete spin-dependent energy of the QD, and and dσ represent the fermionic creation and annihilation operators of the localized electrons in the QD. We assume that an external magnetic field B is applied to the QD resulting in a

• transmission through the QD at , for which the renormalized QD energy level is calculated self-consistently from the relation [34]. We now investigate the effect of an external magnetic field acting only on the QD without affecting the graphene leads. Neglecting the effect of the magnetic field on the

Dynamics of superparamagnetic nanoparticles in viscous liquids in rotating magnetic fields

• Nikolai A. Usov,
• Ruslan A. Rytov and
• Vasiliy A. Bautin

Beilstein J. Nanotechnol. 2019, 10, 2294–2303, doi:10.3762/bjnano.10.221

• coefficient of a particle in a viscous liquid, V is the particle volume, and is the fluctuating rotational moment that describes the free Brownian rotational motion of a particle in a liquid in the absence of an external magnetic field. In accordance with the fluctuation–dissipation theorem [54], the

Targeted therapeutic effect against the breast cancer cell line MCF-7 with a CuFe₂O₄/silica/cisplatin nanocomposite formulation

• B. Rabindran Jermy,
• Vijaya Ravinayagam,
• Widyan A. Alamoudi,
• Dana Almohazey,
• Hatim Dafalla,
• Lina Hussain Allehaibi,
• Abdulhadi Baykal,
• Muhammet S. Toprak and
• Thirunavukkarasu Somanathan

Beilstein J. Nanotechnol. 2019, 10, 2217–2228, doi:10.3762/bjnano.10.214

• expected health crisis [1]. However, the single modal drug delivery system is hampered by low bioavailability (about 5–10%), burst release, and lower target efficiency. Multifunctional theranostic nanoparticles that can respond to an external magnetic field for drug release and assist in bioimaging

• external magnetic field [18]. In the case of CuFe2O4 with x value between 0.08 and 0.15, a lower saturated magnetization value was observed (≤1.0 emu/g), while increasing the x value to 0.17 showed a high magnetization of 7.65 emu/g. In order to understand the cisplatin coordination environment of CuFe2O4

Nitrogen-vacancy centers in diamond for nanoscale magnetic resonance imaging applications

• Alberto Boretti,
• Lorenzo Rosa,
• Jonathan Blackledge and
• Stefania Castelletto

Beilstein J. Nanotechnol. 2019, 10, 2128–2151, doi:10.3762/bjnano.10.207

• has also been proposed to develop a conventional spin-relaxation time sequence. This method is particularly relevant to imaging without an external magnetic field, which may negatively affect sample magnetization. NV center spin relaxation contrast also allows a new all-optical imaging approach

• , fundamental studies of the coupling of photoluminescence and spin properties of NV in diffraction-limited space are carried out by a super-resolution microscope. In the presence of a single ground state spin transition frequency for all emitters, the external magnetic field is used to split the resonant dips

Magnetic properties of biofunctionalized iron oxide nanoparticles as magnetic resonance imaging contrast agents

• Natalia E. Gervits,
• Andrey A. Gippius,
• Alexey V. Tkachev,
• Evgeniy I. Demikhov,
• Sergey S. Starchikov,
• Igor S. Lyubutin,
• Alexander L. Vasiliev,
• Vladimir P. Chekhonin,
• Maxim A. Abakumov,
• Alevtina S. Semkina and
• Alexander G. Mazhuga

Beilstein J. Nanotechnol. 2019, 10, 1964–1972, doi:10.3762/bjnano.10.193

• NMR spectra of 57Fe nuclei in uncoated and HSA-coated samples measured at zero external magnetic field at 4.2 K are shown in Figure 9. The spectra demonstrate a very broad intensity distribution in the range from approximately 62–76 MHz and contain two distinct peaks at 70.9 and 73.0 MHz and a broad

Unipolar magnetic field pulses as an advantageous tool for ultrafast operations in superconducting Josephson “atoms”

• Daria V. Popolitova,
• Nikolay V. Klenov,
• Igor I. Soloviev,
• Sergey V. Bakurskiy and
• Olga V. Tikhonova

Beilstein J. Nanotechnol. 2019, 10, 1548–1558, doi:10.3762/bjnano.10.152

• the unperturbed Hamiltonian of the system, is the external magnetic field and stands for the operator of the magnetic moment. In our approach we firstly take into account three energy states of such artificial Josephson atom: two qubit states with energies E1, E2 and one upper-lying level with

• energy E3 (see Figure 1). The external magnetic field is chosen as unipolar rectangular pulse of duration τ and amplitude A. The key point of our approach is to tune the parameters of the meta-atom and the control circuits in order to apply the magnetic field in a proper way to block the direct

Magnetic segregation effect in liquid crystals doped with carbon nanotubes

• Danil A. Petrov,
• Pavel K. Skokov,
• Alexander N. Zakhlevnykh and
• Dmitriy V. Makarov

Beilstein J. Nanotechnol. 2019, 10, 1464–1474, doi:10.3762/bjnano.10.145

• study the orientational transitions in a suspension of carbon nanotubes in a nematic liquid crystal induced by an external magnetic field. The case of a finite orientational anchoring of liquid crystal molecules at the surface of doped carbon nanotubes is considered. It is shown that in a magnetic field

• the NLC matrix. The total free energy F of such an NLC–CNT suspension in an external magnetic field can be written as follows: Here K11, K22, and K33 are the Frank constants, H is the external magnetic field strength, χa > 0 and are anisotropies of the diamagnetic susceptibility of the NLC matrix and

Superconducting switching due to a triplet component in the Pb/Cu/Ni/Cu/Co₂Cr_1−xFe_xAl_y spin-valve structure

• Andrey Andreevich Kamashev,
• Nadir Nurgayazovich Garif’yanov,
• Aidar Azatovich Validov,
• Joachim Schumann,
• Vladislav Kataev,
• Bernd Büchner,
• Yakov Victorovich Fominov and
• Ilgiz Abdulsamatovich Garifullin

Beilstein J. Nanotechnol. 2019, 10, 1458–1463, doi:10.3762/bjnano.10.144

• involved in the formation of the total moment. Figure 4 shows the dependence of the triplet contribution to the SSV effect on the external magnetic field for the sample PLAK4216. A similar increase of was observed by Singh et al. [14], for which no conclusive explanation can be found at present. This

Tailoring the magnetic properties of cobalt ferrite nanoparticles using the polyol process

• Malek Bibani,
• Romain Breitwieser,
• Alex Aubert,
• Vincent Loyau,
• Silvana Mercone,
• Souad Ammar and
• Fayna Mammeri

Beilstein J. Nanotechnol. 2019, 10, 1166–1176, doi:10.3762/bjnano.10.116

• shape change of the magnetostrictive component under an external magnetic field. Here, the size of the interface between the two components plays a crucial role. Therefore, the development of nanomaterials exhibiting large surface-to-volume ratios can help to respond to such a requirement. However, the

• viewpoint paper about the current limits of such nanostructures [4]. In these materials, the ME coupling arises from a mechanical transmission of strain originating from the shape change of the magnetostrictive component under an external magnetic field, or of the piezoelectric component under an external

• measurements were performed by applying an in-plane external magnetic field (see the Experimental section). The results are presented in Figure 7. For the Co-0.67-TriEG-6 consolidated derivative, a maximal radial magnetostrictive deformation (L − L0)/L0 of −76 ppm has been observed for the demagnetized state

Scavenging of reactive oxygen species by phenolic compound-modified maghemite nanoparticles

• Małgorzata Świętek,
• Yi-Chin Lu,
• Rafał Konefał,
• Liliana P. Ferreira,
• M. Margarida Cruz,
• Yunn-Hwa Ma and
• Daniel Horák

Beilstein J. Nanotechnol. 2019, 10, 1073–1088, doi:10.3762/bjnano.10.108

• , targeting tumor sites using an external magnetic field, MRI contrast agents, or magnetic hyperthermia. Under physiological conditions, the nanoparticle surface is exposed to the action of biomolecules, oxygen, peroxides, and radicals, which changes particle properties and behavior. Moreover, Fe2+ ions can

Magnetic field-assisted assembly of iron oxide mesocrystals: a matter of nanoparticle shape and magnetic anisotropy

• Julian J. Brunner,
• Marina Krumova,
• Helmut Cölfen and
• Elena V. Sturm (née Rosseeva)

Beilstein J. Nanotechnol. 2019, 10, 894–900, doi:10.3762/bjnano.10.90

• -assembled mesocrystalline films, which are formed without the influence of a magnetic field. The remarkable structural difference of mesocrystals produced within the external magnetic field from those self-assembled without field indicates that the specific nanoparticle ordering within the superstructure is

• ]. Due to the superparamagnetic property of the magnetite nanocrystals, their assembly process can be strongly influenced by an external magnetic field which is then labelled as “directed assembly” [21]. The magnetic moment of the magnetic nanocrystals tends to align along a certain crystallographic axis

• within a magnetic field, the so-called “easy axis”. Therefore, superparamagnetic magnetite nanocrystals with an easy axis along <111>magnetite give an extraordinary opportunity to investigate the assembly processes directed by an external magnetic field [22][23][24]. This approach provides an opportunity

Tungsten disulfide-based nanocomposites for photothermal therapy

• Tzuriel Levin,
• Hagit Sade,
• Rina Ben-Shabbat Binyamini,
• Maayan Pour,
• Iftach Nachman and
• Jean-Paul Lellouche

Beilstein J. Nanotechnol. 2019, 10, 811–822, doi:10.3762/bjnano.10.81

• . For WS2-NTs (red spectrum, inset image), the external magnetic field induces a very weak magnetic field in the opposite direction. This means that WS2-NTs are diamagnetic. The CAN-mag curve (green) demonstrates superparamagnetic behavior, where the magnetization increases with the strength of the

Coexisting spin and Rabi oscillations at intermediate time regimes in electron transport through a photon cavity

• Vidar Gudmundsson,
• Hallmann Gestsson,
• Nzar Rauf Abdullah,
• Chi-Shung Tang,
• Andrei Manolescu and
• Valeriu Moldoveanu

Beilstein J. Nanotechnol. 2019, 10, 606–616, doi:10.3762/bjnano.10.61

• oscillations of the transport current in time still reveal Rabi oscillations, but in a complex many-level system other oscillations can be present. In particular we find that for a weak Rabi splitting the even weaker Zeeman spin splitting caused by a small external magnetic field plays a role in the transport

• the z-axis, perpendicular to the two-dimensional quantum wire, inserted to break the spin and possible orbital degeneracies of the states in order to guarantee stability of the results. We use GaAs parameters with m* = 0.067me, κe = 12.4, and g* = −0.44. The small external magnetic field, Bext, and

• doubles, as expected, for both polarization of the cavity field, but the frequency of the slower oscillations is not changed. If the slower oscillations are linked to the Zeeman splitting, then their frequency should change with the small external magnetic field perpendicular to the short quantum wire. In

Heating ability of magnetic nanoparticles with cubic and combined anisotropy

• Nikolai A. Usov,
• Mikhail S. Nesmeyanov,
• Elizaveta M. Gubanova and
• Natalia B. Epshtein

Beilstein J. Nanotechnol. 2019, 10, 305–314, doi:10.3762/bjnano.10.29

• ] and sufficiently high saturation magnetization [5]. However, only nanoparticles with a high specific absorption rate (SAR) in an alternating external magnetic field are suitable for magnetic hyperthermia. Therefore, a significant number of recent experimental studies [6][7][8][9][10][11][12][13][14

• nanoparticles to generate heat in an alternating external magnetic field. According to the present calculations, for interacting magnetite nanoparticles with cubic or combined anisotropy, sufficiently high SAR values of the order of 250–350 W/g can be obtained for low values of magnetic field amplitudes, H0

• that the influence of the magneto–dipole interaction on the assembly behavior is not significant. In addition, isolated nanoparticles can freely rotate in a viscous fluid as a whole under the action of an alternating external magnetic field. This effect gives an additional contribution to the assembly

Relation between thickness, crystallite size and magnetoresistance of nanostructured La_1−xSr_xMn_yO_3±δ films for magnetic field sensors

• Rasuole Lukose,
• Valentina Plausinaitiene,
• Milita Vagner,
• Nerija Zurauskiene,
• Skirmantas Kersulis,
• Virgaudas Kubilius,
• Karolis Motiejuitis,
• Birute Knasiene,
• Voitech Stankevic,
• Zita Saltyte,
• Martynas Skapas,
• Algirdas Selskis and
• Evaldas Naujalis

Beilstein J. Nanotechnol. 2019, 10, 256–261, doi:10.3762/bjnano.10.24

• . (c) Comparison of relative frequency dependence on diameter of the crystallites for the I and II series 370 nm thick films. Magnetoresistance dependence on LSMO film thickness with applied external magnetic field of 0.7 T parallel (B||) and perpendicular (B) to the plane of the film grown from (d

Magnetic-field sensor with self-reference characteristic based on a magnetic fluid and independent plasmonic dual resonances

• Kun Ren,
• Xiaobin Ren,
• Yumeng He and
• Qun Han

Beilstein J. Nanotechnol. 2019, 10, 247–255, doi:10.3762/bjnano.10.23

• resonator–waveguide system. The physical mechanisms of dual resonances are analyzed by the temporal coupled-mode theory. The transmission response to an external magnetic field is explored by using the remarkable tunability of the refractive index of the MF. Based on the different dependence of two

• increases from 1.4623 to 1.464 when the magnetic field H increases from 40 to 100 Oe. Figure 5 shows the transmission spectra as a function of the external magnetic field H. The left resonance at lower wavelengths is more influenced by the magnetic field strength than the right resonance at higher

• variation of magnetic field strength (pm/Oe). The sensitivity obtained here is 27 pm/Oe, i.e., 270 pm/mT, which is excellent compared to other reported values [12][13][14][15]. Because the right resonance is not sensitive to a change of the external magnetic field, it can be used as a reference. This is the

Size limits of magnetic-domain engineering in continuous in-plane exchange-bias prototype films

• Alexander Gaul,
• Daniel Emmrich,
• Timo Ueltzhöffer,
• Henning Huckfeldt,
• Hatice Doğanay,
• Johanna Hackl,
• Muhammad Imtiaz Khan,
• Daniel M. Gottlob,
• Gregor Hartmann,
• André Beyer,
• Dennis Holzinger,
• Slavomír Nemšák,
• Claus M. Schneider,
• Armin Gölzhäuser,
• Günter Reiss and
• Arno Ehresmann

Beilstein J. Nanotechnol. 2018, 9, 2968–2979, doi:10.3762/bjnano.9.276

• widths b of 5 μm, 2 μm, 1 μm, 500 nm, 200 nm and 100 nm were written by HIM in an external magnetic field, applied antiparallel to the initial EB field. For b ≥ 500 nm, the stripe repetition number was chosen to be N = 5, whereas for b < 500 nm, N = 10. The magnetic charge contrast of this pattern

• ferromagnetic (F) layer has been initialized by heating at 573 K for 90 min and subsequent cooling at a rate of 1 K·min−1 for 300 min to room temperature in an external magnetic field of 80 kA·m−1. HIM patterning A commercial HIM (Zeiss Orion Plus) has been modified with a sample holder allowing for the

• application of an in-plane magnetic field of 95 kA·m−1 during ion bombardment. The samples were aligned with their initial EB-field direction pointing antiparallel to the external magnetic field of the holder. 15 keV helium ion bombardment was performed on an area of 500 μm × 500 μm consisting of 216 × 216

Contactless photomagnetoelectric investigations of 2D semiconductors

• Marian Nowak,
• Marcin Jesionek,
• Barbara Solecka,
• Piotr Szperlich,
• Piotr Duka and
• Anna Starczewska

Beilstein J. Nanotechnol. 2018, 9, 2741–2749, doi:10.3762/bjnano.9.256

• carriers must be taken into serious considerations in future experiments. A schematic of the magnetic moment evoked by the PME circulating current in a point-illuminated 2D semiconductor in Corbino configuration (– vector of external magnetic field induction; the green wavey arrow represents illumination

Nanocellulose: Recent advances and its prospects in environmental remediation

• Katrina Pui Yee Shak,
• Yean Ling Pang and
• Shee Keat Mah

Beilstein J. Nanotechnol. 2018, 9, 2479–2498, doi:10.3762/bjnano.9.232

• dioxide sample. The incorporation of magnetite was able to inhibit the photodegradation of the cellulose structure during UV irradiation and this hybrid structure demonstrated high catalyst recyclability using an external magnetic field. Nanoparticles generally tend to aggregate, leading to difficulties

• magnetic field. As a result, magnetic nanomaterials have drawn increasing attention. Nanocellulose incorporated with other magnetic nanomaterials is presented as an excellent composite adsorbent with magnetic properties. For example, a core–shell cellulose magnetite (Fe3O4) polymeric ionic liquid magnetic

• effectively bind metal ions. Conventional cellulose-based adsorbents are difficult to recover from treated wastewater. The recovery step usually requires filtration or high-speed centrifugation. In contrast, magnetic cellulose nanocomposites can easily overcome the recovery issue by application of an external

Influence of the thickness of an antiferromagnetic IrMn layer on the static and dynamic magnetization of weakly coupled CoFeB/IrMn/CoFeB trilayers

• Deepika Jhajhria,
• Dinesh K. Pandya and
• Sujeet Chaudhary

Beilstein J. Nanotechnol. 2018, 9, 2198–2208, doi:10.3762/bjnano.9.206

• was varied (5, 10, 15, 20 and 25 nm). No cooling of the samples in an external magnetic field through the Néel temperature (TN) was performed. For accurately estimating the thicknesses of individual layers and interfacial roughness, X-ray reflectivity (XRR) measurements were performed using a

Interaction-induced zero-energy pinning and quantum dot formation in Majorana nanowires

• Samuel D. Escribano,
• Alfredo Levy Yeyati and
• Elsa Prada

Beilstein J. Nanotechnol. 2018, 9, 2171–2180, doi:10.3762/bjnano.9.203

• , Universidad Autónoma de Madrid, E-28049 Madrid, Spain 10.3762/bjnano.9.203 Abstract Majorana modes emerge in non-trivial topological phases at the edges of specific materials such as proximitized semiconducting nanowires under an external magnetic field. Ideally, they are non-local states that are charge

• annihilation operators, and σ and τ are the Pauli matrices in spin and Nambu space, respectively. The model is defined by setting the parameters m*, μ, α, VZ and Δ, corresponding to the effective mass, the chemical potential, the spin–orbit coupling, the Zeeman energy caused by an external magnetic field, and

Synthesis of a MnO₂/Fe₃O₄/diatomite nanocomposite as an efficient heterogeneous Fenton-like catalyst for methylene blue degradation

• Zishun Li,
• Xuekun Tang,
• Kun Liu,
• Jing Huang,
• Yueyang Xu,
• Qian Peng and
• Minlin Ao

Beilstein J. Nanotechnol. 2018, 9, 1940–1950, doi:10.3762/bjnano.9.185

• indicates that both of the samples show superparamagnetic behavior at room temperature [31]. The maximum saturation magnetizations of Fe3O4/diatomite and MnO2/Fe3O4/diatomite were measured to be 16.57 and 10.61 emu/g, respectively, which make the composites very easy to be separated by an external magnetic

• field (inset). The decrease of the maximum saturation magnetizations after the treatment with KMnO4 is largely ascribed to the outer MnO2 shell, the saturation magnetization of which is much lower than the Fe3O4 nanoparticles. XPS measurements were carried out to determine the surface chemical