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We use a water mist to experimentally visualize the wells in the potential energy of material levitated by a combined diamagnetic-acoustic levitator. The levitator consists of an 18.5 T superconducting magnet, which can levitate diamagnetic material, such as water, plastics, and organic materials, by applying a magnetic body force counteracting the force of gravity. Low-power ultrasound transducers operated at 37.5 kHz generate an acoustic field that spatially modulates the net force acting on the diamagnetically levitated material, making "sonomaglev" capable of levitating multiple objects in stable equilibrium. In these experiments, we levitate a mist of water droplets that are electrically charged so that they repel each other, preventing them from coalescing as a single drop in each of the local potential minima. The shapes of the potential wells are revealed by the shapes of clusters of droplets, which conform to the isosurfaces of the sum of the magnetic, gravitational, and acoustic potentials. The spacing of the droplets in a cluster is shown to depend on their charge, volume, and the force constant of the well in a simple model. Compared to acoustic levitation alone, the combination of diamagnetic and acoustic levitation allows more scope for the manipulation of levitated objects, since the acoustic field is not constrained by the requirement to balance the force of gravity. The method demonstrated here allows the influence on the potential energy of switching on the acoustic field to be observed directly. [ABSTRACT FROM AUTHOR]

A series of Mg doped ZCFAO (Zn0.3−xMgxCu0.7Al0.3Fe1.7O4 (0.05 ≤ x ≤ 0.25) spinel samples were synthesized by solid state reaction method. XRD, was utilized to investigate the structure phase, microstructural characteristics, The optical properties were analyzed; Biological instruments Sp-150 potentiostate is employed to investigate the dielectric measurements in the frequency range of 10 Hz to 1 MHz at various temperatures from 300 to 650 K. Vibrating sample magnetometer VSM was employed to examine the magnetic characteristics in the applied magnetic field ranging from − 20 to 20 kG. The creation of a single-phase cubic spinel was validated by X-ray analysis. The leverage of replacing Zn by Mg leads to enhancement in the lattice parameters, reducing both of the degree of inversion, crystal distortion and compelled these samples to be normal spinel. It turned out that as the degree of inversion sank, the crystallite size declined. The values of dislocations density was found in the order of 10−5 which reveal improving and completing the crystallization of the ferrite samples. The samples have an optical energy gap in the range 3.1–3.38 eV, according to the inferred optical characteristics. The dielectric constant revealed the normal behavior of spinel ferrite it decreases with increasing frequency and enhanced with increasing temperature. It seems that the microstructure of the compound consists of both high-conductive grains and low-conductive grain boundaries, which has been confirmed by the complex impedance. Additionally, the presence of the Maxwell–Wagner relaxation process is also detected. This information can provide valuable insights into the properties and behavior of the compound. Using Nyquist plot, the sample impedance characteristics were interpreted while taking grain and grain boundary contributions into account. The magnetic properties proved that doping ZCFAO with diamagnetic cations (Mg) increases both of saturation magnetization from 16.416 up to 29.983 emu/g and the magnetocrystalline anisotropic constant from 1319.24 to 1612.804 because the two main factors that influence the magnetic properties are the distribution of cations between the octahedral and tetrahedral sites and the magnetic moment of each of its cations. Novelty of our work replacing Zn by Mg (both of them diamagnetic materials) enhance the magnetic properties. Synthesized materials may reexamine the mechanisms underlying Mg2+ induced cationic exchange in ZCFAO and have prospective uses as soft-magnetic materials. [ABSTRACT FROM AUTHOR]

In this study, we successfully fabricated Fe61Zr10Co5Mo7W2B15 and Ni61Nb19.2Ta19.8 amorphous fibers (AFs) using the melt-extraction method. This method ensured a rapid cooling, uniform quality, minimal defects, and superior performance. Magnetic property analysis revealed that the Fe-based AFs exhibited a single-slope magnetization curve characteristic of paramagnetic or diamagnetic materials, while the Ni-based AFs displayed a rectangular curve with low magnetic hysteresis, typical of ferromagnetic materials. The axial saturation magnetization of as-prepared Ni-based AFs is ~1.5 × 10−7 emu/g, with a coercivity of about 85 Oe. The statistical analysis of tensile tests indicated that Ni-based AFs possess a higher fracture threshold of 2440 ± 199 MPa and a reliability of 14.7, demonstrating greater material safety and suitability for high-performance applications. As opposed to Ni-based AFs, Fe-based AFs present a fracture threshold and of 1582 ± 692 MPa and a reliability 4.2. Moreover, under cyclic loading conditions, Ni-based AFs exhibited less residual deformation and superior elastic recovery with a fracture strength of 2800 MPa. These findings highlight the potential of Ni-based AFs for advanced engineering applications, particularly where high strength, durability, and excellent magnetic properties are required, paving the way for their integration into next-generation technologies. [ABSTRACT FROM AUTHOR]

In this paper we report the microwave assisted synthesis and characterization of a family of Na−Ln coordination polymers (CPs) of formula [NaDy2(MeCOO)2(SALOH)5(chpH)2] (1Ln, Ln=Eu, Gd, Tb, Dy, Ho, Y). The Na+ cations isolate Ln2 units in a one‐dimensional polymer. By changing the lanthanoid ions, we attain Single Molecule Magnet properties (1Dy), luminescent properties (1Eu, 1Tb, 1Ho), a diamagnetic material (1Y) and a material that presents magnetocaloric effect (1Gd). [ABSTRACT FROM AUTHOR]

The magnetic levitation (MagLev) of diamagnetic materials in a paramagnetic solution is a robust technique for the density-based separation, measurements, and analysis of bulk materials/objects (e.g., beads and plastics). There is a debate in the literature, however, about whether a MagLev technique is reliable for the separation and/or density measurements of nanoscale objects. Here, we show that MagLev can levitate nanoparticles; however, the transition from the bulk to an 'effective' density must be acknowledged and considered in density measurements at the nanoscale regime. We performed a proof-of-concept study on MagLev's capability in measuring the 'effective density' of multiscale silver particles (i.e. microparticles, nanopowder, and nanoemulsion). In addition, we probed the effective density of nanoscale biomolecules (e.g. lipoproteins) using a standard MagLev system. Our findings reveal that the MagLev technique has the capability to measure both bulk density (which is independent of the size and dimension of the material) and the effective density (which takes place at the nanoscale regime and is dependent on the size and surrounding paramagnetic solution) of the levitated objects. [ABSTRACT FROM AUTHOR]

The aim of this work is to create a new type of gravimeter that can function effectively in the challenging conditions of space, specifically on the surfaces of planets and moons. The proposed device, called a diamagnetically stabilized magnetically levitated gravimeter (DSMLG), uses magnetic forces to balance a test mass against the force of gravity, allowing for accurate measurements. A diamagnetically stabilized levitation structure comprises a floating magnet, diamagnetic material, and a lifting magnet. The floating magnet levitates between two diamagnetic plates without the need for external energy input due to the interaction between the magnetic forces of the floating magnet and the stabilizing force of the diamagnetic material. This structure allows for stable levitation of the floating magnet without requiring additional energy. The goal is to design a gravimeter that is lightweight, requires minimal power, can withstand extreme temperatures and shocks, and has a low data rate. The authors envision this gravimeter being used on various robotic spacecraft, such as landers and rovers, to study the interiors of rocky and icy celestial bodies. This paper reports on the results of a finite element model analysis of the DSMLG and the strength of the resulting diamagnetic spring. The findings contribute to the understanding of the levitation characteristics of diamagnetically stabilized structures and provide valuable insights for their practical applications, including in the development of the proposed DSMLG. [ABSTRACT FROM AUTHOR]

This paper belongs to the area of electrical manipulation of spins in quantum dots and molecular spins for quantum technologies. We propose a theoretical analysis of the electric field controllable superexchange in the two-electron linear arrays of quantum dots ("physical" molecules) and linear mixed-valence molecules based on metal ions in different oxidation degrees ("chemical" molecules) of increasing length. In this view, we consider the kinetic magnetic exchange in trimeric and tetrameric linear arrays of quantum dots and the field dependence of the exchange interaction between electrons. An attainable electric field in these systems is able to essentially change the electronic distribution in the systems under consideration and subsequently to affect the exchange interaction. The numerical estimations demonstrate the feasibility of the revealed effects of the electric field. At a weak electric field, this control is shown to be more efficient for larger numbers of diamagnetic quantum dots mediating superexchange. The peculiarities of chemical analogs of such quantum dot arrays represented by the linear triferrocenium and tetraferrocenium complexes containing two mobile holes are discussed as well. [ABSTRACT FROM AUTHOR]

Researchers seek methods to levitate matter for a wide variety of purposes, ranging from exploring fundamental problems in science through to developing new sensors and mechanical actuators. Many levitation techniques require active driving and most can only be applied to objects smaller than a few micrometers. Diamagnetic levitation has the strong advantage of being the only form of levitation which is passive, requiring no energy input, while also supporting massive objects. Known diamagnetic materials which are electrical insulators are only weakly diamagnetic and require large magnetic field gradients to levitate. Strong diamagnetic materials which are electrical conductors, such as graphite, exhibit eddy damping, restricting motional freedom and reducing their potential for sensing applications. In this work, we describe a method to engineer the eddy damping while retaining the force characteristics provided by the diamagnetic material. We study, both experimentally and theoretically, the motional damping of a magnetically levitated graphite plate in high vacuum and demonstrate that one can control the eddy damping by patterning the plate with through-slots which interrupt the eddy currents. We find that we can control the motional quality factor over a wide range with excellent agreement between the experiment and numerical simulations. [ABSTRACT FROM AUTHOR]

Diamagnetic levitation is a physical phenomenon that uses the diamagnetism of diamagnetic materials to stably levitate itself in an external strong magnetic field, which has great potential in the areas of sensors, actuators, and biomedicine. In this paper, a typical diamagnetic levitation system composed of a NdFeB permanent magnet array and pyrolytic graphite sheet is built. The levitation mechanism of the diamagnetic levitation system is analyzed theoretically, the main factors affecting the static levitation of the pyrolytic graphite sheet are determined, and the influence of structural parameters on the levitation height of the pyrolytic graphite sheet is studied. Furthermore, the dynamic and numerical simulation models of the diamagnetic levitation system are established, and the dynamic response characteristics of the pyrolytic graphite sheet are analyzed under different vibration excitation. This study provides a reference for developing applications based on the diamagnetic levitation system. [ABSTRACT FROM AUTHOR]

Magnetic hyperthermia is beneficial in cancer treatment and in the treatment of some blood vessel diseases. However, excessive temperatures may also kill healthy cells in the vicinity of a sick cell. Using magnetic nanoparticles and changing the nature of the magnetic field as required, magnetic hyperthermia may be regulated in the blood. This research examines the effects of uniform and non-uniform magnetic fields on suspensions of bio-magnetic fluid and nano-bio-magnetic fluid under hyperthermia. Blood is a diamagnetic material, and when combined with superparamagnetic Fe 3 O 4 , its thermo-mechanical characteristics are changed significantly. By manipulating the nature of the magnetic field, it is possible to raise or decrease the temperature in the flow domain of magnetic nano-fluids. A computational study of two such magnetic fields has been conducted, and their effects on the blood-based magneto nano-fluid flow in a rectangular conduit have been documented in this study using COMSOL multi-physics. Results indicate that a uniform magnetic field increases temperature only locally, but decreases the overall temperature in the domain. The non-uniform field of a current-carrying wire decreases both the local maximum and average blood temperature as field strength increases. [ABSTRACT FROM AUTHOR]

• Pd(2+) vs. Pd(3+). • Suggested Revised Structure(s). • DFT Use in IR Spectroscopy. The formulation of the reputed complex [PdCl 2 (L -proline)]∙ L -proline, recently reported by Jiménez-Cruz et al. (J. Molec. Struct., 2023 , 1294 , 136354), is questioned. This postulation is based on the reported diamagnetic nature of the material despite the presence of a presumed formally Pd(3+) metal centre within the crystal lattice. Comments are likewise directed to some aspects of the solution of the crystallographic dataset with respect to the structural elucidation of the reported material. Alternative hypothetical components of the crystalline material isolated in this previous study are put forward to explain some of the anomalies reported for the title compound. [ABSTRACT FROM AUTHOR]

Levitation offers extreme isolation of mechanical systems from their environment, while enabling unconstrained high‐precision translation and rotation of objects. Diamagnetic levitation is one of the most attractive levitation schemes because it allows stable levitation at room temperature without the need for a continuous power supply. However, dissipation by eddy currents in conventional diamagnetic materials significantly limits the application potential of diamagnetically levitating systems. Here, a route toward high‐Q macroscopic levitating resonators by substantially reducing eddy current damping using graphite particle based diamagnetic composites is presented. Resonators that feature quality factors Q above 450 000 and vibration lifetimes beyond one hour are demonstrated, while levitating above permanent magnets in high vacuum at room temperature. The composite resonators have a Q that is >400 times higher than that of diamagnetic graphite plates. By tuning the composite particle size and density, the dissipation reduction mechanism is investigated, and the Q of the levitating resonators is enhanced. Since their estimated acceleration noise is as low as some of the best superconducting levitating accelerometers at cryogenic temperatures, the high Q and large mass of the presented composite resonators positions them as one of the most promising technologies for next generation ultra‐sensitive room temperature accelerometers. [ABSTRACT FROM AUTHOR]

In this work, the structural and magnetic properties of Cr doping at possible sites in the InS monolayer were systematically investigated by density functional theory. The pristine InS monolayer is a diamagnetic semiconductor material of an indirect band gap. Based on our results, doping of the Cr atom at possible lattice sites in the InS monolayer tuned the band gap and induced ferromagnetism in a diamagnetic InS monolayer. Furthermore, the dopant atom induces impurity states within the band gap of the pristine InS monolayer. Thermodynamically, Cr In is the most stable site among all possible doping sites under growth conditions. Therefore, we chose the In site for further investigations. The InS monolayer doped with Cr at the S site shows a half-metallic nature, which is the basic need for the next generation of spintronic devices. Finally, we studied the ferromagnetic (FM) and anti-ferromagnetic (AFM) interactions of dopant atoms by varying the interaction length between the two dopant sites. To estimate the Curie temperature T c , the calculated exchange coupling parameter J = 1.056 meV for two Cr atoms doped at far positions. We found that two Cr atoms lying at the near separation distance prefer the AFM state, while two Cr atoms lying at the far separation distance prefer the FM state. T c estimated for the latter arrangement is 8.17 K (45.27 K) at equilibrium ( - 3 % biaxial strain). We conclude that the substitutional doping of Cr atom(s) in the 2D InS monolayer improved their electronic and magnetic properties, indicating that InS:Cr is a potential candidate for spintronic devices. The Cr atom doped in an InS monolayer at possible doping sites shows a half-metallic nature required for the next generation of spintronic devices. The Cr In is the thermodynamically most stable site among all possible doping sites in both In-rich conditions and S-rich conditions. Therefore, we chose the In site for further investigations. Finally, we have calculated the exchange coupling parameter J for two Cr atoms doped at In sites in an InS monolayer (T = 2/64) lying at near and far positions [see Fig. (a–d)]. We found that two Cr atoms lying near the opposite planes prefer the AFM state [see Fig. (a, b)], while two Cr atoms lying at far separation positions on the same atomic plane prefer the FM state [see Fig. (c, d)]. T c estimated for the latter arrangement is 8.17 K (45.27 K) at equilibrium (−3% biaxial strain). We conclude that the substitutional doping of Cr atom(s) in the InS monolayer improved its electronic and magnetic properties, indicating a suitable candidate for spintronic devices operating above room temperature. [ABSTRACT FROM AUTHOR]

Numerical tools appear to be essential for modeling and designing devices based on superconducting materials. In this article different simulation results are presented, using a computer code based on the finite element method adopted for the resolution of the electromagnetic equations, in the case of an axisymmetric two-dimensional problem, with this code we study the variations of the different electromagnetic quantities. The second generation superconductor has been modeled as an interesting diamagnetic material as inductive pulse sources. The performance in magnetic field resistance, energy storage and thermal stability of the ribbon, known as YBCO, makes it possible to broaden its field of application. Two categories of machines have been proposed and analyzed, the first is classic and the second uses a superconducting ribbon. In addition, a comparative study between the two proposed models is carried out and the results are analyzed and discussed. [ABSTRACT FROM AUTHOR]

In this study, we report the synthesis of a new organic–inorganic molecular salt of the clinically used antifungal drug fluconazole, (H2Fluconazole).SnCl6.2H2O. By detailed investigation and analysis of its structural properties, we show that the structure represents a 0D structure built of alternating organic and inorganic zig-zag layers along the crystallographic c-axis and the primary supramolecular synthons in this salt are hydrogen bonding, F···π and halogen bonding interactions. Magnetic measurements reveal the co-existence of weak ferromagnetic behavior at low magnetic field and large diamagnetic contributions, indicating that the synthesized material behaves mainly as a diamagnetic material, with very low magnetic susceptibility and with a band gap energy of 3.6 eV, and the salt is suitable for semiconducting applications. Extensive theoretical study is performed to explain the acceptor donor reactivity of this compound and to predict the Cl-substitution effect by F, Br and I. The energy gap, frontier molecular orbitals (FMOs) and the different chemical reactivity descriptors were evaluated at a high theoretical level. Calculations show that Cl substitution by Br and I generates compounds with more important antioxidant ability and the intramolecular charge transfer linked to the inorganic anion. [ABSTRACT FROM AUTHOR]

The present study was conducted to investigate the influence of microgravity on human gut microbiota using 16S rRNA gene sequencing in vitro. The diamagnetic material magnetic levitation method was used to simulate weightless environment. The human gut microbiota was cultured under two different conditions: normal gravity (1 g), and simulated microgravity (0 g), which showed that both the richness (P = 0.04) and diversity (P = 0.0002) of human gut microbiota were significantly altered. As compared to the normal gravity, the simulated microgravity significantly reduced abundance of bacteria related to anti-inflammatory effects, such as Subdoligranulum, Faecalibacterium, Fusicatenibacter, Butyricicoccus, and Lachnospiraceae-NK4A136-0 group (P < 0.05), while significantly increased that of Alistipes and Eubacterium-Ventriosum-group (P < 0.05). Moreover, the Spearman's correlation analysis showed that there were more significantly correlated species (|r|≥ 0.5, P < 0.05) in normal gravity than that in the simulated microgravity. KEGG pathway analysis revealed that the microgravity significantly (P < 0.05) affected the metabolism of gut microbiota, such as the metabolism of pyrimidine, fatty acids, glyoxylate and dicarboxylate, peptidoglycan biosynthesis, and carbon fixation in photosynthetic organisms. These results suggested that the exposure to a microgravity environment might induce disturbances in human gut microbiota. Key points: • Using 16sRNA gene sequencing technology, it was found that magnetic levitation-simulated microgravity had varying degrees of influence on the abundance, diversity, species correlation, and KEGG pathways of human intestinal microbes. • Digital PCR can improve the detection rate of microorganisms with low abundance. [ABSTRACT FROM AUTHOR]

In the traditional surface plasmon resonance sensor, the sensitivity is calculated by the usage of angular interrogation. The proposed surface plasmon resonance (SPR) sensor uses a diamagnetic material (Al2O3), nickel (Ni), and two-dimensional (2D) BlueP/WS2 (blue phosphorous-tungsten di-sulfide). The Al2O3 sheet is sandwiched between silver (Ag) and nickel (Ni) films in the Kretschmann configuration. A mathematical simulation is performed to improve the sensitivity of an SPR sensor in the visible region at a frequency of 633 nm. The simulation results show that an upgraded sensitivity of 332°/RIU is achieved for the metallic arrangement consisting of 17 nm of Al2O3 and 4 nm of Ni in thickness for analyte refractive indices ranging from 1.330 to 1.335. The thickness variation of the layers plays a curial role in enhancing the performance of the SPR sensor. The thickness variation of the proposed configuration containing 20 nm of Al2O3 and 1 nm of Ni with a monolayer of 2D material BlueP/WS2 enhances the sensitivity to as high as 374°/RIU. Furthermore, it is found that the sensitivity can be altered and managed by means of altering the film portions of Ni and Al2O3 [ABSTRACT FROM AUTHOR]

The optical transmission, the wavelength and temperature dependence of the Verdet constant as well as the thermally induced depolarization in a Zn 4 B 6 O 13 crystal were investigated. The analytical dependence of the Verdet constant on wavelength and temperature, which describes well the experimental data in the 240–1100 nm range, was obtained. The small coefficient of linear expansion and its isotropy significantly suppressed thermally induced depolarization associated with thermally induced linear birefringence caused by the photo-elastic effect, while the diamagnetic nature of the material ensured the absence of thermally induced depolarization associated with the temperature dependence of the Verdet constant. The results revealed that Zn 4 B 6 O 13 is highly suitable for the wavelength range of 248–350 nm and can be used as a magneto-optical material for an optical isolator for high-average-power UV lasers. [Display omitted] [ABSTRACT FROM AUTHOR]

Partially aligned nickel nanocubes were grown epitaxially in a diamagnetic magnesium oxide (MgO:Ni) host and studied by a continuous wave ferromagnetic resonance (FMR) spectroscopy at the X-band (9.5 GHz) from ca. 117 to 458K and then at room temperature for multiple external magnetic fields/resonant frequencies from 9.5 to 330 GHz. In contrast to conventional magnetic susceptibility studies that provided data on the bulk magnetization, the FMR spectra revealed the presence of three different types of magnetic Ni nanocubes in the sample. Specifically, three different ferromagnetic resonances were observed in the X-band spectra: a line 1 assigned to large nickel nanocubes, a line 2 corresponding to the nanocubes exhibiting saturated magnetization even at ca. 0.3 T field, and a high field line 3 (geff∼6.2) tentatively assigned to small nickel nanocubes likely having their hard magnetization axis aligned along or close to the direction of the external magnetic field. Based on the analysis of FMR data, the latter nanocubes possess an anisotropic internal magnetic field of at least ∼1.0 T in magnitude. [ABSTRACT FROM AUTHOR]

The thermal properties of Ba3Cu2Sn3Se10 were investigated by measurement of the thermal conductivity and heat capacity. The chemical bonding in this diamagnetic material was investigated using structural data from Rietveld refinement and calculated electron localization. This quaternary chalcogenide is monoclinic (P21/c), has a large unit cell with 72 atoms in the primitive cell, and a high local coordination environment. The Debye temperature (162 K) and average speed of sound (1666 m s−1) are relatively low with a very small electronic contribution to the heat capacity. Ultralow thermal conductivity (0.46 W m−1 K−1 at room temperature) is attributed to the relatively weak chemical bonding and intrinsic anharmonicity, in addition to a large unit cell. This work is part of the continuing effort to explore quaternary chalcogenides with intrinsically low thermal conductivity and identify the features that result in a low thermal conductivity. [ABSTRACT FROM AUTHOR]

The thermal properties of Ba3Cu2Sn3Se10 were investigated by measurement of the thermal conductivity and heat capacity. The chemical bonding in this diamagnetic material was investigated using structural data from Rietveld refinement and calculated electron localization. This quaternary chalcogenide is monoclinic (P21/c), has a large unit cell with 72 atoms in the primitive cell, and a high local coordination environment. The Debye temperature (162 K) and average speed of sound (1666 m s−1) are relatively low with a very small electronic contribution to the heat capacity. Ultralow thermal conductivity (0.46 W m−1 K−1 at room temperature) is attributed to the relatively weak chemical bonding and intrinsic anharmonicity, in addition to a large unit cell. This work is part of the continuing effort to explore quaternary chalcogenides with intrinsically low thermal conductivity and identify the features that result in a low thermal conductivity. [ABSTRACT FROM AUTHOR]

Aim Plastic clips are a diamagnetic material and produce fewer artefacts in the MR field than titanium clips, which are standard in neurosurgery. However, alongside their physical properties, the shape of the clips, and their very geometry subtlety affects their behaviour in the magnetic field. Therefore, we performed a simulation in order to establish which clips cause less disturbance in the magnetic field from the point of view of the geometry of the body. Methods The simulation tool used for the research was the software package COMSOL Mph version 4.3. Since it was a question of magnetics, the models were prepared in the AC/DC module within the option Magnetic Fields, No Currents (mfnc). Within this module we were able to analyse electro-magnetic fields for a specific geometrical structure, using the Finite Element Method in order to resolve the two-dimensional electromagnetic problems. Results The value of the magnetic field with titanium clips with their specific geometric reference lines reached the value of c. (A/m). The simpler geometry of the plastic clips resulted in a less intensive magnetic field, amounting to c. (A/m), which is an entire order of magnitude less than the field with the titanium clips. Conclusion The simpler geometry of the plastic clips and the type of material from which they are made causes less disturbance to the magnetic field, which was precisely confirmed with the simulation model. The use of plastic clips in neurosurgery and neuroradiology will facilitate the interpretation of MR images. [ABSTRACT FROM AUTHOR]

The magnetic properties of a polyfluorene derivative, {Poly[9,9'‐dihexylfluorene‐2,7‐yl)‐3,8‐(1,10‐phenanthroline)]} and its complexes with neodymium ions are explored and discussed in the light of the macromolecular configuration and photophysical properties. The pristine noncomplexed material is a diamagnetic material, and the introduction of Nd atoms in the polymer leads to a paramagnetic behavior over the entire temperature range. The prominent role of the morphology is demonstrated by comparison of two forms, with different ligands to the metal: one with bulky β‐diketone groups and another with small chorine as ligands. The large groups hinder interchain interaction, whereas the smaller salt forms favored interchain π‐stacking, providing a better interaction of the magnetic field with the polymer backbone, resulting in enhanced magnetic properties. The form with the β‐diketone groups exhibits a paramagnetic behavior whereas the one in the salt form presents ferromagnetic behavior at room temperature. This contribution brings solid confirmation to the importance of interchain interaction in the magnetic properties of conjugated polymers, opening a new way to the obtainment of magnetic conjugated polymers. [ABSTRACT FROM AUTHOR]

In this study, for the first time the diamagnetic 5d0 Ta5+ ions and Ta2O5 nanocrystals were utilized to enhance the thermal stability, optical linear and nonlinear, and Faraday rotation of diamagnetic glasses. Temperature‐dependent crystal morphology, phases, and structures of Ta2O5 were studied and 50 nm spherical δ‐Ta2O5 nanocrystal was obtained and shown decreased band gap of 3.68 eV. Transparent Ta2O5 nanocrystal doped diamagnetic glasses were obtained, and the embedded Ta2O5 nanocrystals have size ranging from 50 to 80 nm. EDX, XRD, FT‐IR, and Raman analysis indicated that Ta2O5 partially dissolved into glass as TaO6 octahedral units, while partially residual as undissolved Ta2O5 nanocrystals. Ta5+ ions strengthened the network connectivity of 1%–5% Ta2O5‐doped glasses, but Ta5+ acted as network modifier in 10% doped sample and changed the frame coordination units of glass. Therefore, 1% and 5% Ta2O5‐doped glasses showed high Tg and large thermal stability (107° and 120°). All Ta2O5‐doped glasses exhibited broad and intense optical emission at 420 nm, excellent nonlinear refractive index (5.22 × 10−14 cm2/W) and giant Verdet constant (56.19 rad/T·m) due to the increase in density, polarizability, and diamagnetic susceptibility by Ta2O5 doping. [ABSTRACT FROM AUTHOR]

The structure and various components of the electron drift velocity are discussed in application to plasma discharges with the E × B drift. In high density plasmas, the contribution of the diamagnetic drift can be of the same order magnitude as the E × B drift. It is pointed out that curvature and gradient drifts associated with magnetic field inhomogeneities manifest themselves via the electron pressure anisotropy. Estimates show that the components of the diamagnetic drift related to the electron pressure anisotropy and magnetic field gradients can be important for the parameters of modern magnetrons and Hall thrusters. Similar additional terms appear in the momentum balance as mirror forces which may affect the distribution of the electrostatic potential in Hall devices. [ABSTRACT FROM AUTHOR]

We report here the syntheses of a diamagnetic Fe complex [Fe(HL)2] (1), prepared by reacting a redox non-innocent ligand precursor N,N′-bis(3,5-di-tert-butyl-2-hydroxy-phenyl)-1,2-phenylenediamine (H4L) with FeCl3, and its phenoxazine derivative [Fe(L′)2] (2), which was obtained via intra-ligand cyclisation of the parent complex. Magnetic measurements, accompanied by spectroscopic, structural and computational analyses show that 1 can be viewed as a rather unusual Fe(III) complex with a diamagnetic ground state in the studied temperature range due to a strong antiferromagnetic coupling between the low-spin Fe(III) ion and a radical ligand. For a paramagnetic high-spin Fe(II) complex 2 it was found that, when crystalline, it undergoes a thermally induced process where 25% of the molecules in the material change to a diamagnetic low-spin ground state below 100 K. Single crystal X-ray studies conducted at 95 K afforded detailed structural evidence for this partial change of spin state of 2 showing the existence of crystallographically distinct molecules in a 3 : 1 ratio which exist in high- and low-spin states, respectively. Also, the magnetic behaviour of 2 was found to be related with the crystallinity of the material as demonstrated by near-IR radiation to unpaired electrons conversion ability of amorphous sample of 2. [ABSTRACT FROM AUTHOR]

Large magnetic optical rotary dispersion (Faraday rotation) has been demonstrated recently in methylammonium lead bromide. Here, we investigate the prospect of extending the active spectral range by altering the halogen. We also investigate the origins of large Faraday rotation in these diamagnetic materials using magnetic circular dichroism (MCD) spectroscopy and the Kramers–Kronig relations. We find that, while MAPbCl3 (MA = methylammonium) single crystals exhibit a large Verdet constant in the blue, no appreciable Faraday rotation is observed in the red/near infra‐red for MAPbI3 single crystals. However, in all film samples, we find clear evidence of large MCD resulting from the Zeeman splitting of the highly resonant 1s exciton state. Our Kramers–Kronig calculations of Faraday rotation based on MCD data matches well with the dispersion of our experimental data for MAPbCl3 and MAPbBr3, with some deviation in magnitude—demonstrating the excitonic nature of Faraday rotation in these materials. However, our calculations predict significant Faraday rotation in MAPbI3, contrary to our experimental results, indicating a potential discrepancy between the properties of the thin film and single crystal. [ABSTRACT FROM AUTHOR]

Here, we propose the use of magnetic levitation (MagLev) device, as a simple, cheap, and portable experimental technique to measure the density of diamagnetic materials in laboratory settings. We highlight the basics of a standard MagLev system for measuring the density of unknown diamagnetic materials/objects using permanent magnets, paramagnetic solution, and standard density particles. The practical MagLev system enables students to separate and analyse materials based on their density differences both qualitatively and quantitatively. One of the significant advantages of the presented experimental set up is that it is small and fits on conventional laboratory benches, need no power or any other measuring tools, and enables students to measure the density of various diamagnetic materials. We suggest such practical and affordable analytical tool can improve instructional and experimental significance in physics or chemistry laboratories or, to a much extent, in basic sciences classes. [ABSTRACT FROM AUTHOR]

The mean-inner-potential (MIP) of a crystal is the average electrostatic Coulomb potential within a crystal with respect to vacuum. We conducted off-axis electron holography experiments on highly-oriented-pyrolytic-graphite (HOPG) in a transmission-electron-microscope to measure the MIP from nanometer-scale volumes of Bernal graphite oriented with respect to the electron beam, along the principal-axis or directions in the basal plane. These MIP were related to mean orbital electron radii and diamagnetic susceptibilities in perpendicular planes. These measurements are interesting compared to magneto-transport measurements, which report large anisotropy. Along the principal-axis, the susceptibility is highest amongst diamagnetic materials. However, those measurements vary significantly depending on type, size, and thickness of samples, indicating that the signal is significantly extrinsic due to defect induced interfaces. Indeed, structural examination of HOPG show stacking-faults and planar rotations around the principal-axis, such that measuring intrinsic properties requires probing a volume of ∼102 × 102 × 102 nm3. Experiments on such individual graphite crystals with (0001) basal, or (1–100), (2-1-10) prismatic planes, resulted in MIP of 10.16 ± 0.40V, 11.37 ± 0.35V, 12.66 ± 0.41V, respectively. First-principles calculations confirm these anisotropic measurements with 11.72V, 13.65V, 14.56 V, respectively. These measured MIP enable to determine projected mean-radii of electron orbitals and volume susceptibilities at 0.704 ± 0.015 Å, (−1.99 ± 0.08) × 10−5; 0.744 ± 0.015 Å, (−2.23 ± 0.07) × 10−5; 0.785 ± 0.015 Å, (−2.48 ± 0.08) × 10−5. [Display omitted] • The Mean Inner Potential was measured for Bernal graphite crystals with basal and prismatic surfaces. • The MIP measurements are from individual nanometer-scale crystals, enabled by off-axis electron holography in a transmission electron microscope. These measurements are in accordance with our first-principles calculations. • We extracted the electron orbital radii and diamagnetic orbital susceptibility in specified crystallographic planes. • Our reported orbital diamagnetic susceptibilities represent an intrinsic property compared to magnetometry, which is influenced by extrinsic defects. [ABSTRACT FROM AUTHOR]

4-Phenyl-3-thiosemicarbazide reacts with 2,3-butanedione to provide a new compound, diacetyl-bis(N4-phenyl-3-thiosemicarbazonato) (H2ATSP). In the presence of triethylamine (Et3N), the reaction of H2ATSP with NiCl2 affords a new nickel complex, diacetyl-bis(N4-phenyl-3-thiosemicarbazonato)nickle(II) (NiII-ATSP), a diamagnetic material, which has been characterized by physicochemical and spectroscopic methods. Studies exhibit that Ni-ATSP has good catalytic activities for both electrochemical and photochemical driven hydrogen evolution. Under an overpotential (OP) of 837.6 mV, 188.7 moles of hydrogen per mole of catalyst per hour (mol H2/mol catalyst/h) are afforded from an electrolysis of neutral water with Ni-ATSP. With blue light (λ = 469 nm) irradiation, together with CdS nanorods (CdS NRs) as a photosensitizer, and ascorbic acid (H2A) as a sacrificial electron donor, Ni-ATSP can catalyze hydrogen generation with a turnover number (TON) of 9554 moles H2 per mol of catalyst (mol of cat−1) during 50 h irradiation in a heterogeneous environment. [ABSTRACT FROM AUTHOR]

Peter Day’s research group reported the first molecular superconductor containing paramagnetic metal ions in 1995, β″-(BEDT-TTF)4(H3O)Fe(C2O4)3·C6H5CN. Subsequent research has produced a multitude of BEDT-TTF-tris(oxalato)metallate salts with a variety of structures and properties, including 32 superconductors to date. We present here the synthesis, crystal structure, and conducting properties of the newest additions to the Day series including the first superconductor incorporating the diamagnetic tris(oxalato)aluminate anion, β″-(BEDT-TTF)4(H3O)Al(C2O4)3·C6H5Br, which has a superconducting Tc of ~2.5 K. β″-(BEDT-TTF)4(H3O)Co(C2O4)3·C6H5Br represents the first example of a β″ phase for the tris(oxalato)cobaltate anion, but this salt does not show superconductivity. [ABSTRACT FROM AUTHOR]

We show that the standard concepts of nonlinear response to electromagnetic fields break down in two-dimensional Dirac systems, like graphene, in the quantum regime close to the Dirac point. We present a compelling many-body theory for nonlinear transport focusing on disorder scattering as a benchmark example. We show that, although the diamagnetic two-photon vertex is absent at the non-interacting level, disorder effects give rise to a self-generation of such two-photon vertex surviving even in the clean limit. We predict that the two-photon vertex self-generation is present only in two dimensions. The impact of such a striking scenario on the nonlinear quantum transport is discussed, predicting a huge enhancement of third-order dc conductivity comparing to the common models. [ABSTRACT FROM AUTHOR]

The effect of bound polaron on the thermodynamic properties of GaAs quantum dot (QD) with a quadratic potential in the presence of electromagnetic field is presented. The Schrödinger method as well as the canonical ensemble approach has been used to determine the energy of polaron and the thermodynamic properties such as heat capacity, entropy, and magnetic susceptibility with the help of canonical partition function. We found that the heat capacity increases with a potential confinement angle and also with temperature, and decreases with the increase in the magnetic field. This reduction in the heat capacity shows that our system behaves as a refrigerator. Furthermore, an increasing in magnetic field reduces the disorder in the quantum dot. Indeed, a strong increase in the magnetic field is much better for a good confinement of particles. Moreover, we found that the materials with low coupling constant avoid disorder in the quantum system. The polaron is therefore a good protector of the quantum dot against the external effects. We also found that an increasing temperature increases the speed of electrons and also for very small values of magnetic field, the system stores more energy. It is worthy to mention that our approach is consistent with the characteristic behavior of the diamagnetic materials, well-known as GaAs quantum dots. [ABSTRACT FROM AUTHOR]

Using a set of methods of physicochemical analysis, the effect of a constant magnetic field during the process of electrospark treatment in air on diffusion and phase formation in diamagnetic materials is studied. The form of concentration profiles, the mobility of alloying atoms in the coating and substrate, and the parameters of solid solutions depending on the presence and direction of the magnetic field are established. The influence of the value of the magnetic induction on the interaction of copper with silver during electrospark alloying is shown and the phases formed are determined. [ABSTRACT FROM AUTHOR]

Recently, it was found that the ferromagnetic SrRuO3 when combined with another ferromagnet in thin film form gives rise to exchange bias (EB) effect. However, we observed EB in single, strained, SrRuO3 thin films grown on diamagnetic LaAlO3 (100) substrates. It displays the training effect, which essentially confirms EB. The temperature dependence of the EB reveals the blocking temperature to be around ≈75 K. The strength of the exchange bias decreases with the increase in thickness of the film. We observe tensile strain in the out of plane direction. Further, the presence of in-plane compressive strain is observed through asymmetric reciprocal space mapping. Finally, we find a direct link between strain and EB. The evolution of strain with thickness matches well with the nature of scaled EB. It has been shown earlier by first principle calculations that this strain can induce EB in thin films. [ABSTRACT FROM AUTHOR]

We investigate the oscillating magnetocaloric effect on a size-quantized diamagnetic film in a transverse magnetic field. We obtain the analytical expression for the thermodynamic potential in case of the arbitrary spectrum of carriers. The entropy change is shown to be the oscillating function of the magnetic field and the film thickness. The nature of this effect is the same as for the de Haas-van Alphen effect. The magnetic part of entropy has a maximal value at some temperature. Such behavior of the entropy is not observed in magneto-ordered materials. We discuss the nature of unusual behavior of the magnetic entropy. We compare our results with the data obtained for 2D and 3D cases. [ABSTRACT FROM AUTHOR]

Employing very simple electro-mechanical principles known from classical physics, the Kibble balance establishes a very precise and absolute link between quantum electrical standards and macroscopic mass or force measurements. The success of the Kibble balance, in both determining fundamental constants (h, N A , e) and realizing a quasi-quantum mass in the 2019 newly revised International System of Units, relies on the perfection of Maxwell's equations and the symmetry they describe between Lorentz's force and Faraday's induction, a principle and a symmetry stunningly demonstrated in the weighing and velocity modes of Kibble balances to within 1 × 10 - 8 , with nothing but imperfect wires and magnets. However, recent advances in the understanding of the current effect in Kibble balances reveal a troubling paradox. A diamagnetic effect, a force that does not cancel between mass-on and mass-off measurement, is challenging balance maker's assumptions of symmetry at levels that are almost two orders of magnitude larger than the reported uncertainties. The diamagnetic effect, if it exists, shows up in weighing mode without a readily apparent reciprocal effect in the velocity mode, begging questions about systematic errors at the very foundation of the new measurement system. The hypothetical force is caused by the coil current changing the magnetic field, producing an unaccounted force that is systematically modulated with the weighing current. Here we show that this diamagnetic force exists, but the additional force does not change the equivalence between weighing and velocity measurements. We reveal the unexpected way that symmetry is preserved and show that for typical materials and geometries the total relative effect on the measurement is ≈ 1 × 10 - 9 . [ABSTRACT FROM AUTHOR]

Burning rate modulation of solid fuel can improve the performance of solid fuel ramjet over a wider altitude or Mach number envelopes. To better control the burning rate of a solid fuel, the effect of magnetic fields on the regression rate of solid fuel was experimentally and numerically investigated. In this experiment, the regression rates of polymethyl methacrylate (PMMA) rods under different types of magnetic field gradients were measured. Meanwhile, the morphological changes in the flame during combustion were recorded by a complementary metal-oxide semiconductor (CMOS) camera. The experimental results indicated that the regression rate for PMMA varies regularly with various magnetic field gradients, with rates in the range from -32.5% to 10.8%. Simultaneously, the flame structure also changes. The numerical simulation that considered both gas-phase combustion and gas-solid heat transfer produced results that were in good agreement with the experiment. The results show that the change in the regression rate is a result of the magnetic force acting on the paramagnetic and diamagnetic materials. By changing the flow field, the magnetic force can change the flame shape and temperature distribution. This alters the heat exchanged between the gas and the fuel surface and thus, changes the burning rate. It was found that the burning rate of solid fuel can be adjusted regularly by applying different types of non-uniform magnetic fields, and it may be used in the solid fuel ramjet burning rate modulation. [ABSTRACT FROM AUTHOR]

High-energy electrons observed in the magnetosheath must be accelerated by some mechanism that is as yet undetermined. We present observations of high-energy electrons trapped in diamagnetic cavities as measured by Magnetospheric Multiscale from 2015 to 2018. The observations support the notion of local acceleration in the reconnection quasi-potential as many of events show particles with pitch angles that are increasingly closer to 90° with increasing energy. It is suggested that these particles can end up in the loss cone and be transported to the magnetosheath. We also characterize each diamagnetic cavity as formed due to low- or high-latitude reconnection based on prevailing solar wind conditions. The character of the ions in the diamagnetic cavity is only briefly mentioned as their properties warrant another stand-alone investigation. [ABSTRACT FROM AUTHOR]

Intrinsic and Te-doped GaAsSb nanowires with diameters ~100–120 nm were grown on a p-type Si(111) substrate by molecular beam epitaxy (MBE). Detailed magnetic, current/voltage and low-energy electron energy loss spectroscopy measurements were performed to investigate the effect of Te-doping. While intrinsic nanowires are diamagnetic over the temperature range 5–300 K, the Te-doped nanowires exhibit ferromagnetic behavior with the easy axis of magnetism perpendicular to the longitudinal axis of the nanowire. The temperature dependence of coercivity was analyzed and shown to be in agreement with a thermal activation model from 50–350 K but reveal more complex behavior in the low temperature regime. The EELS data show that Te doping introduced a high density of states (DOS) in the nanowire above the Fermi level in close proximity to the conduction band. The plausible origin of ferromagnetism in these Te-doped GaAsSb nanowires is discussed on the basis of d0 ferromagnetism, spin ordering of the Te dopants and the surface-state-induced magnetic ordering. [ABSTRACT FROM AUTHOR]

A series of Zr1-xNixO2 nanocrystalline powders were synthesized by chemical route and then calcined at 750 °C for 5 h. A mixed phase of monoclinic and tetragonal phase of ZrO2 has been observed in XRD patterns and Raman studies. The tetragonal phase of ZrO2 increases up to a Ni concentration of x = 0.025 and thereafter suppression of the tetragonal phase is observed with the increase in monoclinic phase of ZrO2. At lower concentration of Ni of x = 0.01, the material manifests with diamagnetic property and then a diamagnetic to ferromagnetic transition is established at above than x = 0.01. The saturation magnetization increases with increase in Ni concentration up to x = 0.025 and then decreases for Ni concentration of x = 0.03 in Ni substituted ZrO2. The sudden fall in saturation magnetization in Zr0.97Ni0.03O2 arises due to the superexchange interactions between two neighboring Ni2+ ions which lead to antiferromagnetism in the material and suppress the ferromagnetic ordering. [ABSTRACT FROM AUTHOR]

In the present study, the effect of Ni, Co, and Fe carbon‐based magnetic fillers (Ni‐C, Co‐C, and Fe‐C) was investigated on the magnetic, mechanical, thermal, and morphological properties of polyethylene nanocomposites. The in situ polymerization technique was used to prepare nanocomposites of polyethylene from the ethylene monomer introducing small amounts of filler ranging from 1 to 2 wt.%. The metal‐carbonized fillers were obtained by pyrolysis of wood sawdust activated by Ni, Co, or Fe salts. X‐ray diffraction showed that the fillers were of nanometric size. Thermogravimetric analysis was executed to investigate the thermal strength of the materials as well as to calculate the metal content in the carbon‐based fillers. The onset degradation temperature showed an enhancement of 17°C, whereas the maximum degradation temperatures increased 4°C with the introduction of the filler. Differential scanning calorimetry indicated an improvement of 3°C in crystallization temperature, whereas the melting temperature remained unchanged compared to neat polyethylene. The filler was shown to increase the modulus of elasticity of the nanocomposites. The addition of 1.0 wt.% of the metal‐carbonized material in the diamagnetic polymer matrix resulted in a thermoplastic nanocomposite with ferromagnetic behavior. POLYM. ENG. SCI., 60:988–995, 2020. © 2020 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

The constant magnetic field is an effective tool of influence during alloy crystallization, distribution of components and properties of alloys, including aluminum ones. The field with the flux density B < 1T is especially promising, since its creation does not require much energy and costs. Application of the magnetic field is hampered due to its complex effect on the alloys' structure, the mechanism of which is not completely studied. A constant magnetic field with B =0.25T redistributes additional components with different magnetic characteristics in the alloy with a paramagnetic base (Al). Its action is the most significant in increasing the diamagnetic additive (Cu) content in the grain (which brings its amount in the cast alloy closer to the heat-treated metal), the ferromagnetic one (Fe) at the periphery of grains (which increases grain alloying) and the paramagnetic addition (Ti) in the center of the grain (which enhances the effect of the modifier). It has been found that the constant magnetic field reduces the dendritic liquation of copper. Decreasing the concentration of Cu, along with increasing Ti content in the volume of several grains, reduces the depth of the alloy intergranular corrosion. [ABSTRACT FROM AUTHOR]

Metal matrix composite materials are a class of materials with improved mechanical, thermal and radiation resistance properties. They are used in several specific applications in nuclear and energy industry. Also, there are different applications due to improved wear resistance and mechanical strength. Best materials are those with very fine (nano-scaled) particles which are evenly distributed and fully dispersed inside the metal matrix. Such materials are difficult to produce, because separation and dispersion of small particles is a complicated task. Our research is aimed at investigating possibilities to use a strong electromagnetic, contactless interaction to disperse particles in liquid metal alloys. [ABSTRACT FROM AUTHOR]