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The search for spin-reorientation (SR) phase transitions, a spontaneous rotation of ordered magnetic moments, in ferrimagnetic (FiM) materials, which carry a net magnetization, is of fundamental and practical interest for applications in the field of spintronics. In this work, we have investigated Mn self-doped (Er 0.7 Mn 0.3)MnO 3 solid solution with GdFeO 3 -type Pnma perovskite structure by combining specific heat, magnetic susceptibility and neutron powder diffraction measurements. We provide experimental evidence for FiM order below T C = 104 K, and a spontaneous SR transition at T SR = 11 K. A FiM structure appears in all (R 1-x Mn x)MnO 3 compounds with R = Dy–Lu for x ≥ 0.2. But in this structural family, R = Er is the only material with a SR transition. FiM order in (Er 0.7 Mn 0.3)MnO 3 appears with ferromagnetic (FM) ordering of Mn3+ and Mn4+ cations at the B site along the a -direction, which are antiferromagnetically (AFM) coupled with Er3+ and Mn2+ cations at the A site. At T SR , ordered Er3+ change direction from the magnetically harder a -axis to the magnetically easy b -axis and induce a change of the whole FiM structure, including the direction of all Mn spins from the irreducible representation m GM3+ to m GM4+. We calculated the crystal-field (CF) anisotropy for Ho3+ in (Ho 0.8 Mn 0.2)MnO 3 and Er3+ in (Er 0.7 Mn 0.3)MnO 3 , based on the point charge model; the results revealed large magnetic anisotropies. For the FiM structure of (Ho 0.8 Mn 0.2)MnO 3 , the magnetically easy a -axis of Ho3+ keeps the high-temperature magnetic directions along the a -axis and gives rise to a pronounced magnetization reversal effect at low temperature because of a significant rise of Ho3+ ordered moments. On the other hand, for the FiM structure of (Er 0.7 Mn 0.3)MnO 3 , the magnetically easy b -axis of Er3+ gives rise to a SR phase transition at T SR , which does not lead to magnetization reversal even though Er3+ ordered moments rise significantly at low temperatures. [ABSTRACT FROM AUTHOR]

This study investigates Co 40 Fe 40 Dy 20 thin films on glass substrates with thicknesses ranging from 10 nm to 50 nm under four conditions: as-deposited, annealed at 100 °C, 200 °C, and 300 °C. X-ray diffraction (XRD) confirms film amorphousness due to limited thermal energy. Maximum low-frequency alternate-current magnetic susceptibility (χ ac) is observed at thicker films and higher annealing temperatures, with films at 300 °C showing the highest value 0.41. Annealing at 200 °C yields exceptional properties high saturation magnetization (M s) 748 emu/cm³ and low coercivity (Hc) 10 Oe, though Ms decreases at 300 °C due to thermal effects. Electrical resistivity and sheet resistance decrease with thickness and annealing, enhancing carrier transport. Transmittance (%) decreases notably with increased thickness, attributed to thickness and interface effects. Variations in surface roughness from annealing affect properties, with smoother surfaces improving carrier conductivity but reducing optical transparency. Overall, Co 40 Fe 40 Dy 20 exhibits excellent soft magnetic properties suitable for various applications. [ABSTRACT FROM AUTHOR]

The mountainous region of central Shandong Province in eastern China is renowned for its high frequency of rainstorms, which often result in devastating flood disasters and have profoundly affected the evolution of local ancient civilizations. To identify ancient flood disaster events, recognizing sediment signatures via multiple indices is important. Here, we investigated the 2018 flood deposits in the Danhe River Basin and sampled short core DH2, on which the grain size, total organic matter (TOM) content, carbonate content, magnetic susceptibility (MS) and pollen were measured. The fine grain size of the flood sedimentary layer reveals that the flood energy in the alluvial plain area is usually weak. The pollen species and concentration and the tree pollen content in the flood layer are significantly greater than those in the soil layer, suggesting that the flood sediment mainly originates from the mountainous areas in the upper reaches of the river, which provides more forest vegetation information. The MS of flood deposits is lower than that of the soil layer, which is mainly related to the intensity of pedogenesis. The research results indicate that the flood sediments in the downstream floodplain areas of small watersheds are predominantly composed of fine-grained components, with characteristics of high loss on ignition, low magnetic susceptibility, high pollen abundance and diverse species. These findings establish a multi-index identification system for paleoflood sedimentation, which has important reference significance for the study of paleoflood sedimentology and hydrology. [ABSTRACT FROM AUTHOR]

The Li-ferrite and graphene oxide (GO) nanocomposites, denoted as (Li 0.5-x/2 ZnₓFe 2.5-x/2 O 4 : x = 0.25), were produced through ultrasonication. The wet method generated Li-ferrite, while the Hummers' method synthesized the GO. X-ray diffraction (XRD) was used to validate the development of Li-ferrite and GO in the nanocomposites. The dimensions of the crystal were determined between 41 and 52 nm, and the porosity of the composites increased with the higher quantity of GO. The scanning electron micrographs (SEM) of ferrites illustrated the formation of uniform and well-defined grains with consistent shapes, exhibiting properties well-suited for effective microwave absorption. The electrical resistance of spinel ferrite was measured at approximately 3.34 × 1011 Ω-cm and significantly lowered as the fraction of GO increased at ambient temperature. As per Maxwell Wagner's model, the electrical permittivity exhibited interfacial polarization with distinct real and imaginary components. The AC conductivity exhibited a positive correlation with the GO content due to the conductive properties of GO and the improved charge hopping mechanism. The frequency exponent parameter's value falls from 0.36 to 0.95 b y the Jonscher's Power law. The magnetic susceptibility of all the samples exhibited a progressive decrease as the temperature increased. The choice of using lithium-based ferrite as filler is made to strengthen the ferrite/GO composites and improve their magnetic and electrical properties. This is undertaken to harness these composites for high-frequency applications, such as their use as microwave absorbers in microwave devices. [ABSTRACT FROM AUTHOR]

Physical-property-based patterning is an alternative biofabrication approach that relies on the application of a remote field, and the intrinsic properties of the objects or materials of interest, to simply create complex tissues. Both buoyant and gravitational forces can rapidly create tissue gradients without any hardware, highlighting the appeal of in situ density-based patterning. Recent advances now allow for the magnetic patterning of naturally diamagnetic cells using paramagnetic solutions, including crosslinkable hydrogels. New methods have been developed to change the compressibility of a cell, enabling differential cell separation and alignment within an acoustic field. The field of biofabrication is rapidly expanding with the advent of new technologies and material systems to engineer complex tissues. In this opinion article, we introduce an emerging tissue patterning method, physical-property-based patterning, that has strong translational potential given its simplicity and limited dependence on external hardware. Physical-property-based patterning relies solely on the intrinsic density, magnetic susceptibility, or compressibility of an object, its surrounding solution, and the noncontact application of a remote field. We discuss how physical properties can be exploited to pattern objects and design a variety of biologic tissues. Finally, we pose several open questions that, if addressed, could transform the status quo of biofabrication, pushing us one step closer to patterning tissues in situ. [ABSTRACT FROM AUTHOR]

Fire is an essential component of the landscapes and forests of the Pacific Northwest, including the temperate rainforests of the Olympic Peninsula. Previous fire history reconstructions from the peninsula show that fire return intervals varied throughout the postglacial period, primarily in response to climatic changes and corresponding shifts in vegetation. However, much less is known about the fire history of the low-elevation forests of the Olympic Peninsula and the role of cultural fire regimes in these environments. The purpose of this study was to reconstruct the paleoenvironmental history of a low-elevation study site, Beaver Lake, located in the northwestern part of the peninsula. Using macroscopic charcoal, pollen, and sedimentological analyses of a ca. 3440-year-long record, we reconstructed a high-resolution record that shows fire activity was remarkably high during the late Holocene for an area considered part of a temperate rainforest. However, patterns of burning varied throughout the record, with the first third (ca. 3440 to 2350 cal yr BP) and last third (ca. 800 cal yr BP to the present day) recording much higher amounts of fire activity compared to the middle portion (ca. 2350 to 800 cal yr BP), which recorded very little fire activity. Larger and/or more severe fires that likely burned during multi-year droughts correlate with peaks in magnetic susceptibility and pollen trends that indicate substantial geomorphic responses and successional changes in forest structure following these events. Cooler temperatures and a wetter climate, indicated by nearby glacial advancements, may have staved off fire activity during the period of low fire activity. Cultural burning by the Indigenous tribes of the Olympic Peninsula likely contributed to the observed fire activity at Beaver Lake as nearby prairies were managed for resource procurement, indicated in particular by an increase in herbaceous morphotype charcoal during the past 800 years. [ABSTRACT FROM AUTHOR]

Worldwide, Quaternary loess-paleosol sequences archive terrestrial paleoenvironmental information. The Palouse loess in the northwestern USA is one such deposit representing at least a million years of sediment accumulation. Loess paleosol sequences are often studied via the magnetic susceptibility of sediments and the changes in susceptibility with depth. However, since variations in magnetic susceptibility can have different underlying causes, the interpretation of the magnetic susceptibility of loess depends on factors specific to each major loess region. We measured the magnetic susceptibility of sediments along depth profiles in a well-studied exposure of the Palouse loess in eastern Washington, USA (the "CLY-2 site," 46.3131° N, 118.4874° W, WGS84). Our measurements show that the magnetic susceptibility of sediments in the Palouse loess varies systematically and predictably with depth and can be correlated with other magnetic susceptibility profiles at the outcrop scale and at the regional scale. We also measured changes in grain size, elemental abundance, mineralogy, and other magnetic properties to determine the most likely cause of the magnetic susceptibility signal. Based on these results, variations in magnetic susceptibility in the Palouse are likely driven mostly by changes in coarse sediment supply and accumulation of tephra rather than changes in weathering. Magnetic susceptibility is useful as an inexpensive, non-destructive tool for stratigraphic correlation of Quaternary loess deposits in the Palouse, especially in combination with paleosol stratigraphic markers and known tephra deposits. [ABSTRACT FROM AUTHOR]

Metallic biomaterials, such as stainless steels, cobalt–chromium–molybdenum (Co–Cr–Mo) alloys, and titanium (Ti) alloys, have long been used as load-bearing implant materials due to their metallic mechanical strength, corrosion resistance, and biocompatibility. However, their magnetic susceptibility and elastic modulus of more than 100 GPa significantly restrict their therapeutic applicability. In this study, spinodal Zr 60 Nb 40 , Zr 50 Nb 50 , and Zr 40 Nb 60 (at.%) alloys were selected from the miscibility gap based on the Zr–Nb binary phase diagram and prepared by casting, cold rolling, and aging. Their microstructure, mechanical properties, corrosion resistance, magnetic susceptibility, and biocompatibility were systematically evaluated. Spinodal decomposition to alternating nanoscale Zr-rich β 1 and Nb-rich β 2 phases occurred in the cold-rolled Zr–Nb alloys during aging treatment at 650 °C. In addition, a minor amount of α phase was precipitated in Zr 60 Nb 40 due to the thermodynamic instability of the Zr-rich β 1 phase. Spinodal decomposition significantly improved the mechanical strength of the alloys due to nanosized dual-cubic reinforcement. The Zr–Nb alloys showed an electrochemical corrosion rate of 94–262 nm per year in Hanks' solution because of formation of dense passive films composed of ZrO 2 and Nb 2 O 5 during the polarization process. The magnetic susceptibilities of the Zr–Nb alloys were significantly lower than those of commercial Co–Cr–Mo and Ti alloys. The cell viability of the Zr–Nb alloys was more than 98 % toward MC3T3-E1 cells. Overall, the spinodal Zr–Nb alloys have enormous potential as bone-implant materials due to their outstanding overall mechanical properties, extraordinary corrosion resistance, low magnetic susceptibility, and sufficient bicompatibility. This work reports on spinodal Zr–Nb alloys with heterostructure. Spinodal decomposition significantly improved their mechanical strength due to the nanosized dual-cubic reinforcement. The Zr–Nb alloys showed large corrosion resistance in Hanks' solution because of formation of dense passivation films composed of ZrO 2 and Nb 2 O 5 during the polarization process. The magnetic susceptibilities of the Zr–Nb alloys were significantly lower than those of commercial Co–Cr–Mo and Ti alloys. The cell viability of the Zr–Nb alloys was more than 98 % toward MC3T3-E1 cells. The results demonstrate that spinodal Zr–Nb alloys have enormous potential as bone-implant materials due to their outstanding overall mechanical properties, high corrosion resistance, low magnetic susceptibility, and sufficient biocompatibility. [Display omitted] [ABSTRACT FROM AUTHOR]

Field-to-susceptibility inversion in quantitative susceptibility mapping (QSM) is ill-posed and needs numerical stabilization through either regularization or oversampling by acquiring data at three or more object orientations. Calculation Of Susceptibility through Multiple Orientations Sampling (COSMOS) is an established oversampling approach and regarded as QSM gold standard. It achieves a well-conditioned inverse problem, requiring rotations by 0°, 60° and 120° in the yz -plane. However, this is impractical in vivo , where head rotations are typically restricted to a range of ±25°. Non-ideal sampling degrades the conditioning with residual streaking artifacts whose mitigation needs further regularization. Moreover, susceptibility anisotropy in white matter is not considered in the COSMOS model, which may introduce additional bias. The current work presents a thorough investigation of these effects in primate brain. Gradient-recalled echo (GRE) data of an entire fixed chimpanzee brain were acquired at 7 T (350 μm resolution, 10 orientations) including ideal COSMOS sampling and realistic rotations in vivo. Comparisons of the results included ideal COSMOS, in-vivo feasible acquisitions with 3–8 orientations and single-orientation iLSQR QSM. In-vivo feasible and optimal COSMOS yielded high-quality susceptibility maps with increased SNR resulting from averaging multiple acquisitions. COSMOS reconstructions from non-ideal rotations about a single axis required additional L2-regularization to mitigate residual streaking artifacts. In view of unconsidered anisotropy effects, added complexity of the reconstruction, and the general challenge of multi-orientation acquisitions, advantages of sub-optimal COSMOS schemes over regularized single-orientation QSM appear limited in in-vivo settings. [ABSTRACT FROM AUTHOR]

The composite MoO 3 / Me MoO 4 (Me = Cu, Ni, Co, Fe, and Mn) ceramics were obtained by standard high-temperature sintering. Their structure was tested using XRD, SEM, EDS, and XPS. The occurrence of two phases was determined. The main MoO 3 phase exhibited an orthorhombic Pnma space group related to the ceramic grain of micrometre size. The second phase was induced by doping with the Me atom. It showed various monoclinic structures and a smaller grain size. The XPS test confirmed the coexistence of the phases, which was reflected in several lines in the patterns. The valence band of the undoped MoO 3 was located ∼3.3 eV below the Fermi level. An additional subband attributed to the Me 3d state was detected within the energy gap. The MoO 3 / Me MoO 4 composites showed a valence band shifted toward the Fermi level and overlapped with the subband, originating from hybridized Mo 4d – Me 3d states. Magnetic susceptibility showed an antiferromagnetic state below ∼20 K for the Ni- and Fe-doped composites. The estimated magnetic moment magnitudes indicated the contribution from Me 2+ and Me 3+ ions that marked the occurrence of oxygen vacancies. Diffuse reflectance spectra exhibited anomalies in the Vis (∼500–650 nm) and the NIR (∼700–850 nm) ranges and tails in the ∼900–1000 nm range. The estimated magnitudes of energy gaps were attributed to defect-induced states. They corresponded to deduced oxygen vacancies (2.05–2.38 eV) and states or subbands induced by the introduced Me atoms (1.34–1.89 eV). Electric dc resistivity temperature dependence showed thermally activated dependence. The estimated activation energy varied from 0.27 eV to 0.58 eV, depending on the doping of the Me atom. The electric features were consistent with the electronic structure determined using XRD and XPS tests. [ABSTRACT FROM AUTHOR]

Dense ceramic samples of wolframite-type MnMoO 4 (w -MnMoO 4) have been prepared by Cool-SPS (Spark Plasma Sintering) for the first time with the goal of investigating the magnetic, dielectric, and magneto-electric properties of this thermally fragile polymorph of MnMoO 4. Earlier studies found that w -MnMoO 4 converts to the structurally different α-MnMoO 4 phase if heated in air at 873 K, thus hindering fabrication of w -MnMoO 4 ceramics by conventional high-temperature sintering. Unsintered powder samples, which were prepared via a hydrothermal method, and dense ceramics elaborated by Cool-SPS have the same magnetic properties. Magnetic susceptibilities display Curie-Weiss behaviour, χ = C/(T-θ), with effective moments for Mn2+ ion μ eff ≈ 5.9 μ B /Mn-atom and negative Weiss temperatures θ ≈ - 96 to - 98 K. Unlike the isostructural multiferroic compounds MnW 1-x Mo x O 4 (0 ≤ x < 0.3) which exhibits at least two successive magnetic transitions below 15 K, w -MnMoO 4 undergoes only one paramagnetic-to-antiferromagnetic transition at T N ≈ 32 K. The field-dependent magnetization at 2 K shows a spin-flop transition at μ 0 H SF ≈ 2 T. Capacitance and dielectric losses obtained for a ceramic between 2 and 300 K in zero field and in a field of 9 T reveal several weak anomalies. Dielectric anomalies are observed at the magnetic phase transition, suggesting a magnetoelectric coupling. Qualitatively different dielectric and magnetodielectric behaviours occur in α-MnMoO 4 ceramics at low temperature. [ABSTRACT FROM AUTHOR]

Development of efficient photothermal catalysts made of earth-abundant elements is of prime importance for heterogeneous photocatalysis driven by solar light. Herein, we report for the first time the synthesis of NiTi@TiO 2 /Ni core-shell-satellite nanoparticles from pristine nitinol nanopowder (NiTi) by simple and easily scalable ultrasonically assisted hydrothermal treatment in pure water (T = 200 °C, P = 14 bar, f = 20 kHz, P ac = 17 W, τ = 3 h). Prepared material exhibits unique set of properties, such as strong capability of light-to-heat conversion, good magnetization, high stability, and remarkable thermally assisted photocatalytic hydrogen production (5.5 mmol h−1 g−1 at T = 90 °C). The core-shell-satellite morphology of NiTi@TiO 2 /Ni particles maximizes the contact area between the heat generating metallic core and photocatalytically active TiO 2 /Ni nanocrystalline shell providing the most efficient photothermal effect in the processes of H 2 production and CO 2 methanation without CO emission. In addition, significant magnetic susceptibility of the NiTi@TiO 2 /Ni nanoparticles allows their easy recovery from solution with an external magnetic field. Noncongruent surface oxidation of nanoalloys reported in this work paves the way to the preparation of new generation of catalysts with advanced photothermal properties. [Display omitted] • NiTi@TiO 2 /Ni photocatalyst was prepared from NiTi nanopowder by ultrasonically assisted hydrothermal treatment in water. • Obtained material exhibits strong capability of light-to-heat conversion, good magnetization, and high stability. • NiTi@TiO 2 /Ni nanoparticles exhibit remarkable activity for thermally assisted photocatalytic hydrogen production. • This material enables CO 2 methanation by in situ generated hydrogen in aqueous solutions. [ABSTRACT FROM AUTHOR]

The improvement of the archaeomagnetic dating method requires compiling new and older data of the Earth's magnetic field (EMF) variations for the last millennia. Combustion events from fumier sequences have been proposed as good directional EMF recorders. However, they are subjected to diverse taphonomical processes and how these affect the archaeomagnetic record has not yet been studied. In order to evaluate it, here we report the first archaeomagnetic and rock-magnetic results on samples from experimentally recreated fumiers since 2014 under controlled conditions. A facies description with unprecedent resolution was used to study the variation of magnetic properties in depth. Rock-magnetic analyses indicate a homogenous magnetic mineralogy dominated by pseudo-single domain magnetite as main carrier in all facies, with not very high and similar contribution of the finest (superparamagnetic) grains. The low values of anisotropy of magnetic susceptibility (AMS) indicate that the studied sample set is mainly isotropic. The directional behaviour in well-preserved burned facies (here described as G, LM and DGB), are jointly characterized by highly reversible thermomagnetic curves, high Koenigberger (Q n) ratio values and intense, univectorial and normal polarity orthogonal NRM demagnetization diagrams. On the contrary, specimens affected by mechanical alteration processes are less magnetic and show anomalous directional behaviours. The high thermomagnetic reversibility of ashes indicates that they reached ca. 600–700 °C, in line with the thermocouples' data. Temperatures of 460 °C were obtained for the DGB facies (subyacent black carbonaceous facies). Sampling of ashes located on the top of these combustion events should be avoided for archaeomagnetism. Being just beneath the last stabling episode they are the most prone to undergo mechanical alterations and do not preserve well the Earth's magnetic field direction. Despite their unlithified nature and the multiple taphonomic processes that fumier sequences may undergo, under certain quality criteria, they are valid geomagnetic field recorders providing both information of archaeological and geophysical interest. [ABSTRACT FROM AUTHOR]

The glaciers of the Tibetan Plateau have undergone profound changes due to rapid global warming, but the nature of their response to climate change at various settings remains unclear. This study focuses on the analysis (grain sizes, magnetic susceptibility, and element ratios) of a sedimentary core from a proglacial lake (Qiangyong (QY) Co) at the southern Tibetan Plateau, based upon the 210Pb and 137Cs dating, aiming to unveil the fluctuations of the QY glacier over the recent 500 years and its response to global warming. Four pre-1900s distinct glacier advance/cold intervals (C1: 1560s, C2: 1660s, C3: 1760s and C4: 1860s), a minor advance in the 1950s and an extensive glacier retreat since the 2010s were discerned. There are five glacier fluctuation cycles, each spanning approximately 100 years, correlating generally well with the Northern Hemisphere temperature patterns on a century time scale. The glacier advances align with the cold periods, whereas the retreats correspond to the warm intervals. However, coarse grain sizes indicated a marked glacier shrinkage of the QY glacier since the 1920s owing to global warming, over-shading the inherent 100-years fluctuation cyclic variations intrinsic to glaciers. The reason is that after QY glacier has significantly shrunk to higher altitude, the response of the glacier to climate change is no longer as sensitive as at the lower altitude, even under post-industrial-revolution warming. The QY glacier and even the entire Himalayan region will face the threat of glacier melting during the 21st century, but dynamic patterns of glacier retreats in higher Himalayan regions may differ from that in the low-altitude. [ABSTRACT FROM AUTHOR]

This study reports on the properties of glasses and glass-ceramics isolated in a novel ternary system Na 2 O–NiO-(1-x)P 2 O 5 –xV 2 O 5 with varying concentrations of V 2 O 5 (x = 0, 0.2, 0.4, and 0.6 mol%). The materials were prepared by melting the mixture of reagents with stoichiometric proportions. Their amorphous and crystalline nature was confirmed via the XRD analysis. The vitreous feature and thermal parameters of the glasses were explored using differential scanning calorimetry. The density values have shown an increase and a slight decrease in the molar volume with the increase in the V 2 O 5 content. The elemental composition of the glass and glass-ceramics was studied using energy-dispersive X-ray spectroscopy. In addition, the study examined the influence of the composition on the structure of the materials using both IR and Raman spectroscopies. XRD analysis of annealed samples revealed the presence of different crystalline phases depending on the V 2 O 5 content. The EPR results were influenced by the variation of concentration of V 2 O 5 and indicated the presence of V4+ ions in octahedral sites with tetragonal compression. The analysis of the magnetization according to the magnetic field at different temperatures showed a ferromagnetic behavior at low temperatures and a paramagnetic one at higher temperatures for all glasses. Magnetic susceptibility data reveal a Curie-Weiss behavior and the predominance of antiferromagnetic interactions. The dielectric studies were conducted as a function of temperature and frequencies to evaluate the composition effect on the dielectric constant, dielectric loss, and ionic conductivity. Electrical features were also examined using impedance spectroscopy. [ABSTRACT FROM AUTHOR]

Herein, the structure, thermal stability, optical, magnetic characteristics, and adsorption performance towards methylene blue (MB) of Sn 1- x Zn 2 x Cr 2 O 5 nanocomposites (x = 0, 0.2, 0.4, 0.5, 0.6, 0.8, and 1), prepared by the hydrothermal method, were investigated. The crystal structures, elemental chemical compositions and surface morphology were conducted using XRD, TEM, EDX, and SEM techniques. The structural parameters significantly depend on the elemental composition. For example, a tetragonal SnO 2 phase was formed at x = 0, and 0.2, while a spinel-structured ZnCr 2 O 4 was formed at x ≥ 0.4 beside the orthorhombic CrO 3 phases. The mass magnetic susceptibility and magnetization of the Sn 1- x Zn 2 x Cr 2 O 5 nanocomposites displayed a weak room temperature ferromagnetism behavior. The maximum surface area (100.89 m2/g), evaluated via the Brunauer-Emmett-Teller method, was achieved for Sn 0.6 Zn 0.8 Cr 2 O 5 nanocomposite. The optical band gap and Urbach energy show opposite trends and are slightly influenced by Zn content. Moreover, the impact of the Zn2+ ratio on the structure, optical, thermal stability, and magnetic characteristics was correlated. The adsorption performance of the Sn 1- x Zn 2 x Cr 2 O 5 nanocomposite (0 ≤ x ≤ 0.6) revealed an excellent removal efficiency (max ∼87.64%) towards MB dye with apparent rate kinetic constant of 44.9 × 10–2 min–1. [ABSTRACT FROM AUTHOR]

The AMUSED (A MUltidisciplinary Study of past global climatE changes from continental and marine archives in the MeDiterranean region) project aims at improving knowledge of late Quaternary climate variability and its expressions in different geological settings of the Mediterranean region. In this framework, the Castiglione maar, in the Colli Albani Volcanic District, central Italy, was selected for acquiring a high-resolution and geochronologically well-constrained multi-proxy record by drilling the entire lacustrine succession. Electrical Resistivity Tomography (ERT) profiles were acquired across the central portion and the SW crater edge to depict the geometry of the sedimentary infilling and select the best drilling site. Two parallel cores (C1 and C2), 116 m- and 126.5 m-depth respectively, were recovered from the central sector of the Castiglione basin, where, according to ERT profiles, the sedimentary succession reaches the maximum thickness. The sedimentary infilling consists of fine-grained sediments: mainly fine sand, silt and clay, with minor gravel intervals and numerous tephra layers and volcaniclastic lenses. Specifically, more than 60 tephras were identified and used, alongside other lithostratigraphic features, to correlate the C1 and C2 cores and to assemble a composite section. The variability in magnetic susceptibility, led by glacial-interglacial cycles, and the geochemical fingerprinting of key tephra layers allowed to establish a preliminary chronological framework for the Castiglione succession which certainly spans the last 365 ka, with a mean sedimentation rate of 0.33 mm/yr. The relatively long time span of the Castiglione maar succession arises as a new potentially meaningful node of the network of Mediterranean records for better reconstructing the late Quaternary climate dynamics on a regional and extra-regional scale. [ABSTRACT FROM AUTHOR]

We report a new cancer imaging modality in the contrast of tissue intrinsic susceptibility property by computed inverse magnetic resonance imaging (CIMRI). In MRI physics, an MRI signal is formed from tissue magnetism source (primarily magnetic susceptibility χ) through a cascade of MRI-introduced transformations (e.g. dipole-convolved magnetization) involving MRI setting parameters (e.g. echo time). In two-step computational inverse mappings (from phase image to internal fieldmap to susceptibility source), we could remove the MRI transformations and imaging parameters, thereby obtaining χ-depicted cancer images (canχ) from MRI phase images. Canχ is computationally implemented from clinical cancer MRI phase image by CIMRI. As a result of MRI effect removal through computational inverse mappings, the reconstructed χ map (canχ) could provide a new cancerous tissue depiction in contrast of tissue intrinsic magnetism property (i.e. diamagnetism vs paramagnetism) as in an off-scanner state (e.g. in absence of main field B 0). Through retrospective clinical cancer MRI data analysis, we reported on the canχ method in technical details and demonstrated its feasibility of innovating cancer imaging in the contrast of tissue intrinsic paramagnetism/diamagnetism property (in a cancer tissue state free from MRI effect). [ABSTRACT FROM AUTHOR]

Citrate auto-combustion method was employed to create Bi-perovskite (BFO), Zn-ferrite (ZFO) and Sr-hexaferrites (SFO) nanoparticles, which were then mixed up to form matrix composite which used to separate the lead metal ions from wastewater. Based on XRD peaks, the crystallite size was between 30 and 52 nm. The particles' FTIR spectra clearly show that each synthesized compound has unique functional groups. The samples had agglomeration, with each agglomerate including many grains, as shown by the SEM micrographs. The energy band gap of SFO was enhanced and reduced from 3.5 to 1.5 eV by adding BFO and ZFO. For magnetic study, T C as well as μ eff of BFO and ZFO were improved by adding SFO. While the dielectric properties for pure SFO was enhanced after adding BFO and ZFO in the nanocomposite, in this research paper author succeed in preparing nanosample with upgrading magnetic, optical and electric properties more than individual samples' properties. The synthetic BFO/ZFO/SFO nanocomposite produced impressive results in the treatment of wastewater due to their enormous surface area, regulated size, well-defined structure, and high magnetic, optical and electric properties. Kinetic and isotherm analysis are applied to the experimental results. The high correlation coefficient indicates the adsorption of heavy metal ions, which is described by the Langmuir and Freundlich isotherms (R2). For the 97% removal of Pb (II) from wastewater at a contact duration of 40 min at room temperature and pH 7. [ABSTRACT FROM AUTHOR]

To understand if unexplained signal artifacts in MRg-LITT proton resonance frequency- (PRF-) shift thermometry images are caused by air bubbles or hemorrhages, and to characterize their effects on temperature measurements. Retrospective image data from an IRB-approved clinical trial of intracranial MRg-LITT were inspected for asymmetric distortions observed in phase data during ablations, which have been previously reported as likely hemorrhages. A total of eight patient cases were selected: seven with artifact occurrence and one without. Mathematical image models for air bubbles or hemorrhages were implemented to estimate the size of the air bubble or hemorrhage needed to explain the clinically observed phase artifacts. Correlations and Bland-Altman analyses were used to determine if an air bubble model or a hemorrhage model was better correlated to the clinical data. The model was used to inject bubbles into clean PRF phase data without artifacts to examine how temperature profile distortions change with slice orientation. The simulated air-bubble injected data were compared to clinical data containing artifacts to examine the bubbles' effects on temperature and thermal damage estimates. The model demonstrated that air bubbles up to approximately 1 cm in diameter could explain the clinically observed phase artifacts. The bubble model predicts that a hemorrhage would have to be 2.2 times as large as an air bubble in order to explain the same extent of phase distortion observed in clinical data. Air bubbles had 16% percent higher correlations to the clinical PRF phase data than hemorrhages, even after rescaling the hemorrhage phases to better match the data. The air bubble model also explains how the phase artifacts lead to both large positive and large negative temperature errors, up to ±100 °C, which could cascade to damage estimate errors of several millimeters. Results showed that the artifacts are likely caused by air bubbles rather than hemorrhages, which may be introduced before heating or appear during heating. Manufacturers and users of devices that rely upon PRF-shift thermometry should be aware these phase distortions from bubble artifacts can result in large temperature errors. [ABSTRACT FROM AUTHOR]

The magnetic susceptibility is a reflection of minerals like the iron oxide that affect the pore system. This work applied the magnetic susceptibility as an effective indicator of reservoir quality. A total of (38) sandstone samples were collected from the Nubia Group exposed in Northeast Aswan, representing the Sabaya, Abu Agag and Um Bramil Formations. The samples were petrophysically examined in terms of porosity, grain density, bulk density, permeability and magnetic susceptibility (κ). Reservoir quality index (RQI) and distribution of the sample within the Global Hydraulic Elements (GHEs) were determined. Several relations constructed between (κ) as a function of iron oxides and the measured properties. The results showed Sabaya and Abu Agag samples are characterized by the highest average values of κ, (287 & 219SI) respectively, matched with the lowest average values of porosity, permeability, RQI and the highest average values of grain & bulk density, hence most samples lie in the lower quality zones (GHE-1, 2, 3 and 4). On the contrary, the lowest average value of (κ) is (37.9 SI) for Um Bramil samples, matched with the highest average values of porosity, permeability, RQI and the lowest average values of grain & bulk density, hence most samples lie in the higher quality zones (GHE-6, 7 and 8). Petrographic description showed the tight and wide pore system relation to the magnetic susceptibility values. The novelty here is utilizing the magnetic susceptibility as an effective pointer for the reservoir quality expectation and classification into hydraulic units. [ABSTRACT FROM AUTHOR]

To explore the factors controlling the spatiotemporal variability of dust magnetic susceptibility (SUS) across tectonically stable (Chinese Loess Plateau, CLP) and tectonically active (eastern Tibetan Plateau, ETP) regions, the SUS and grain-size records of the Jingyuan and Lantian loess‒paleosol deposits from the CLP, and Lixian lacustrine sediments from the ETP, were analyzed. The results show that, spatially, SUS decreases substantially from SE to NW in the CLP, and from the CLP to the ETP; and temporally, SUS increases significantly both in the CLP and the ETP during warm periods. The former is consistent with pedogenic contributions previously proposed, while the later responds to the enhanced seismic activities and foehn effect during warm period. The correlation analysis shows that the strongest positive correlation between SUS and 2–10 μm fractions in the CLP indicates a substantial contribution of fine particles to magnetic minerals, which has been underestimated in the earlier studies. The strongest positive correlation between SUS and coarse‒grained fractions in ETP reveals that SUS is mainly controlled by frequent release of magnetic minerals from bedrock caused by tectonic activities. These results reflect different controlling factors of SUS changes under different tectonic backgrounds. Therefore, the correlation analysis between SUS and grain‒size fractions can be used as a simple and effective method to sensitively reveal regional tectonic activity, and effectively trace the Earth surface processes including material supply, transport dynamics, and sedimentology. [ABSTRACT FROM AUTHOR]

In soils of the temperate zone, there is an increase in the magnetic susceptibility χ of an upper layer compared to χ C of parent rocks. The difference between χ and χ C characterizes the magnetic "enhancement" Δχ, which is usually considered as associated with mean annual precipitation (MAP), allowing the reconstruction of MAP of the past from Δχ values of paleosols. which is widely enough used. However, in regions with a wide MAP range, non-monotonic dependence of Δχ on MAP is observed, making this reconstruction ambiguous. To construct climatic functions for reconstructing the past climate, we subdivided the south of European Russia into three regions, where climatic functions such as MAP(Δχ) of modern soils are monotonic and close to linear. These regions are relatively dry, humid, and semi-humid cold. We considered an extended set of climatic features including potential evapotranspiration (PET), actual evapotranspiration (AET), water deficit (WD = PET–AET), moisture index (MI = MAP/PET), an index of De Martonne (IDM = MAP/(MAT+10), where MAT is the mean annual temperature). The links of Δχ with MAP were positive in dry and negative in humid and semi-humid cold where they are weaker, but there were closer links with temperature-dependent WD and PET. Reliable (with R 2 > 0.7) climatic functions were constructed for dry and semi-humid cold, but such reliable functions were absent in humid part. Since the differences in soil - forming material, it is necessary to identify some parameter to characterize lithological factors. For this reason, we include in consideration median grain sizes (lgSz) in soil profiles and total iron (Fet) to obtain some explanations for the results. Although the use of Δχ, lgSz and Fe t together made the climatic functions more reliable (R 2 ∼ 0.8), but Δχ played the main role, while lgSz and Fe t were not always significant. Based on the obtained data, it appears possible to provide a more detailed subdivision of paleoecological periods in the Late Holocene for the steppe and forest-steppe zones of the Eastern Europe. Taking into account the diversity of soil conditions in different regions, equations using soil profile MS enhancement to reconstruct rainfall should be used locally and regionally, taking into account the identified limitations and eliminating the possible ambiguity of reconstructions. [ABSTRACT FROM AUTHOR]

Differentiation of calcification and calcium-containing tissue from blood products remains challenging using magnetic resonance imaging (MRI). We developed a novel post-processing algorithm which creates both paramagnetic- and diamagnetic-specific SWI images generated from T2* weighted images using distinct "positive" and "negative" phase masks. 10 patients who had undergone clinical MRI scanning of the brain with a rapid echo planar based T2*-weighted EPI-GRE pulse sequence with evidence for either hemosiderin and/or calcifications were retrospectively identified. Complex raw k-space data from individual imaging coils were then extracted, reconstructed, and appropriately combined to produce magnitude and phase images using a phase preserving method. The final reconstructed images included the T2* EPI-GRE magnitude images, p-SWI and d-SWI images. Filtered phase images were also available for review. Correlation with CT scans and MR imaging appearance over time corroborated the composition of the voxels. Differential "blooming" of diamagnetic and paramagnetic foci was readily identified on the corresponding p-SWI and d-SWI images and provided fast and reliable visual differentiation of diamagnetic from paramagnetic susceptibility effects by ascertaining which of the two images depicted the greatest "blooming" effect. Correlation with the available filtered phase maps was not necessary for differentiation of paramagnetic from diamagnetic image components. Clinical interpretation of SWI images can be further enhanced by creating specific p-SWI and d-SWI image pairs which contain greater visual information than the combination of standard p-SWI images and phase image. [Display omitted] • New concept of individually reconstructed diamagnetic and paramagnetic specific SWI images: Current clinical/commercially available SWI post-processing algorithms only create images which enhance the paramagnetic component of susceptibility (e.g. p-SWI specific susceptibility weighted images). • In this work we separately reconstruct diamagnetic and paramagnetic susceptibility weight images (d-SWI, p-SWI) and use these to better discriminate hemosiderin from calcification. • The algorithm is described pictorially in the attached diagram. • The phase masks were applied exponentially to the magnitude image, with exponent of 4 for p-SWI and 5 for d-SWI. [ABSTRACT FROM AUTHOR]

Soil loss is a global environmental problem resulting from the erosion process caused by many factors, including land use and slope position. Estimation of total soil loss from agricultural fields is useful for understanding the consequences of historical and current erosion. The main purposes of the current study are to explore the application of magnetic measurements in the mapping and measuring soil redistribution in cultivated (MZ13) and forested (MZ17) transects in a Moroccan subcatchment, to develop a methodological approach correlating magnetic susceptibility (MS, denoted χ) variation to soil erosion/aggradation, and to discriminate the effects of land-use change and slope position on the total cumulative soil loss, assessed using three recently established erosion models based on an MS parameter. MS measurements were done on several soil cores collected at different slope positions including the summit (SU), shoulder (SH), back slope (BS), foot slope (FS), toe slope (TS) for Transects MZ13 and MZ17. A tillage homogenization (T-H) model, simple correlation model (SCM), and simple proportional model (SPM) based on χ lf (where lf indicates low frequency) were applied to estimate soil loss for each slope position in the two transects. The results show that the correlation between χ lf and χ fd (which is the frequency-dependent magnetic susceptibility percentage) is positive and high for the two transects (R 2 = 0.95; p < 0.01). The results confirm that the χ lf enhancement of soils selected in calcareous parent material is related to the pedogenic processes with the formation of superparamagnetic particles distributed along the slope positions. The current study proves that it is possible to trace and monitor soil erosion and deposition using magnetic parameters (χ lf and χ fd %) for different slope positions along cultivated and forested transects. The results confirm that the soil losses strongly depend on land use and slope position. Higher erosion depth (d) estimated using the three erosion models are comparable and were about d (T-H, BS17L) = −154.9 cm, d (SCM, BS17L) = −142.3 cm, and d (SPM, BS17L) = −143.6 cm for MZ17 Transect, and about d (T-H, FS13M) = −156.3 cm, d (SCM, TS13L) = −143.8 cm, d (SPM, FS13M) = −145.9 cm for MZ13 Transect. The applied models indicate that the strong losses take place in the upper and lower slopes of the cultivated transect, and in the middle and lower slopes of the forested transect. [ABSTRACT FROM AUTHOR]

To investigate the relationship between pathological brain iron deposition and white matter hyperintensities (WMHs) in cerebral small vessel disease (CSVD), via Monte Carlo simulations of magnetic susceptibility imaging and the development of a novel imaging marker called the Expected Iron Coefficient (EIC). A synthetic pathological model of a different number of impenetrable spheres at random locations was employed to represent pathological iron deposition. The diffusion process was simulated with a Monte Carlo method with adjustable parameters to manipulate sphere size, distribution, and extracellular properties. Quantitative susceptibility mapping (QSM) was performed in a clinical dataset to study CSVD to derive and evaluate QSM, R2*, the iron microenvironment coefficient (IMC), and the EIC in the presence of WMHs. The simulations show that QSM signals increase in the presence of increased tissue iron, confirming that the EIC increases with pathology. Clinical results demonstrate that while QSM, R2*, and the IMC do not show significant differences in brain iron, the EIC does in the context of CSVD. The EIC is more sensitive to subtle changes in brain iron deposition caused by pathology, even when QSM, R2*, and the IMC fail. [ABSTRACT FROM AUTHOR]

The presence of orientation-dependent susceptibility artifacts in magnetic resonance chemical shift thermometry (CST) can confound accurate temperature calculations. Here, we quantify the effect of white matter (WM) tract orientation on CST due to tissue-specific susceptibility. Twenty-nine healthy volunteers (27 ± 4 years old) were scanned on a 3 T MR scanner with a 32-channel head coil. Diffusion tensor imaging (DTI), T1-weighted imaging, and single voxel spectroscopy (SVS) for CST were acquired. Participants were then asked to rotate their head ∼3–5° (yaw or roll) to alter the orientation of WM tracts relative to the external magnetic field. After head rotation, a second SVS scan and T1-weighted imaging were acquired. The WM-fraction-normalized DTI principal eigenvector (V1) images were used to calculate the length of the x-y component of V1, which was used as a surrogate for WM tracts perpendicular to B 0. A linear regression model was used to determine the relationship between the perpendicular WM tracts and brain temperature. Significant temperature differences between post- and pre-head rotation scans were observed for brain (−0.72 °C ± 1.36 °C, p = 0.01) but not body (0.012 °C ± 0.07 °C, p = 0.37) temperatures. The difference in brain temperature was positively associated with the corresponding change in perpendicular WM tracts after head rotation (R2 = 0.26, p = 0.005). Our results indicate WM tract orientation affects temperature calculations, suggesting artifacts from orientation-dependent susceptibility may be present in CST. [ABSTRACT FROM AUTHOR]

We report experimental studies on a series of Rb(Co 1 − x Ni x) 2 Se 2 (0.02 ≤ x ≤ 0.9) powder and single crystal samples using x-ray diffraction, neutron diffraction, magnetic susceptibility, and electronic transport measurements. All compositions are metallic and adopt the body-centered tetragonal structure with I 4 / m m m space group. Anisotropic magnetic susceptibilities measured on single crystal samples suggest that Rb(Co 1 − x Ni x) 2 Se 2 undergo an evolution from ferromagnetism to antiferromagnetism, and finally to paramagnetism with increasing Ni concentration. Neutron diffraction measurements on the samples with x = 0.1, 0.4, and 0.6 reveal an A -type antiferromagnetic order with moments lying in the a b plane. The moment size changes from 0.69 (x = 0. 1) to 2.80 μ B (x = 0. 6) per Co ions. Our results demonstrate that dilution of the magnetic Co ions by substitution of nonmagnetic Ni ions induces magnetic localization and evolution from itinerant to localized magnetism in Rb(Co 1 − x Ni x) 2 Se 2. • Dilution of Co ions in Rb(Co 1 − x Ni x) 2 Se 2 enhances the moment size of the Co ions. • Replacing Co with Ni tunes the ground state progressively. • The superconductivity in RbNi 2 Se 2 is suppressed by 10% Co-doping. • Rb(Co 1 − x Ni x) 2 Se 2 is a suitable platform to investigate two-dimensional magnetism.. [ABSTRACT FROM AUTHOR]

• Centimeter-scale Ni 2 SiO 4 single crystals are grown by a flux method. • Magnetization up to 43 T of polycrystalline shows six phase transitions at H 1 = 14 T, H 2 = 18.4 T, H 3 = 23 T, H 4 = 29 T, H 5 = 32.5 T, and H 6 = 37 T. • M is linear with H in phases V and VII, intercepting at 0 and half M saturation, respectively. • These phenomena in the triangular chain Ni 2 SiO 4 underscore its potential for studying complex magnetic interactions. Sub-centimeter-scale Ni 2 SiO 4 single crystals were grown by a flux method with K 2 MoO 4 as the flux. The obtained crystals exhibit high quality and were characterized using X-ray diffraction, chemical analysis, and magnetic properties, including high magnetic field (H) magnetization (M) measurements. The results of magnetic susceptibility and specific heat of a single crystal reveal significant magnetic anisotropy and antiferromagnetic ordering below T N = 30 K. High-field magnetization up to 43 T of polycrystalline shows six magnetic phase transitions at H 1 = 14 T, H 2 = 18.4 T, H 3 = 23 T, H 4 = 29 T, H 5 = 32.5 T, and H 6 = 37 T, forming a complex magnetic phase diagram with seven phases. Notably, the M exhibits a linear relationship with H during phases V (H 4 < H < H 5) and VII (H > H 6), showing intercepts at 0 and half of magnetization saturation respectively, implying the presence of a spin flop transition and a 1/2 magnetization plateau. These novel phenomena in such a triangular chain system highlight complex physical nature, making Ni 2 SiO 4 a promising candidate for studying intricate magnetic interactions. [ABSTRACT FROM AUTHOR]

A family of Cu(II) halide complexes with cationic N -donor ligands has been prepared and analyzed by single-crystal X-ray diffraction, variable temperature and field magnetic susceptibility and EPR. [Display omitted] Copper (II) complexes of the cationic ligands 1-(4′-pyridyl)-pyridinium (L1) and 1-(4′-pyridyl)-pyridin-4-ol (L2) have been prepared and characterized by single crystal X-ray diffraction and variable temperature magnetic susceptibility measurements: [Cu(L1) 2 X 2 ]X 2 [where X = Cl (1), Br (2)], and [Cu(L2) 2 X 2 ]X 2 [where X = Cl (3), Br (4)]. The complexes are fundamentally square planar with L 2 X 2 coordination planes and long, semi-coordinate bonds to the additional halide ions. All compounds crystallize in monoclinic systems with 1 and 2 in the P 2 1 / n space group and 3 and 4 in the P 2 1 / c space group. The crystal structures are stabilized by both non-classical (in the case of 1 and 2) and classical (3 and 4) hydrogen bonds. EPR data for 1 – 4 support a rhombohedral structure, in good agreement with the local geometry as seen in the crystal structures. Magnetic susceptibility measurements show the presence of very weak antiferromagnetic interactions. In addition, the syntheses and magnetic properties of two neutral complexes, [Cu(L3) 2 X 2 ]·2H 2 O [L3 = 1-(4′-pyridino)-4-pyridone; X = Cl (5), Br (6)] are reported. Magnetic susceptibility data indicate the presence of moderate antiferromagnetic exchange interactions [J ∼ 28 K (5), 60 K (6)] which were well modeled by the S = 1/2 Heisenberg uniform chain model. [ABSTRACT FROM AUTHOR]

A deep-sea sediment record from the Western Alboran Basin spanning the last 37 kyr has been analysed using a multiproxy approach, integrating sediment colour, magnetic susceptibility, elemental ratios, benthic foraminiferal assemblages and bioturbation, gaining new insights into Alboran Basin deep-sea environments and palaeoceanographic conditions since the Last Glacial Maximum. The combination of a diverse set of proxies made it possible to recognise the diagenetic signals and reconstruct new low-frequency events in the deep basin, recording the significant fluctuations in deep water oxygenation occurred during the studied period. From the studied data, short-term periodic low-oxygen events are recognised during Heinrich Stadials 2 and 3 (HS2 and HS3) and Greenland Interstadial GI8, showing important responses of the deep sea environments to climate climate change. Furthermore, the presence of a not previously well-defined Organic Rich Layer 2 (ORL 2) can be defined from the observations as a sequence of events transitioning between low oxygen (associated with humid conditions and Heinrich Events) and oxygenated conditions, and not as a singular low oxygenation event. In addition, the Organic Rich Layer 1 (ORL1), associated with the most recent low oxygen event has been also recognised in the record, with low oxygen conditions starting as early as 16 kyr before the present (BP) during the HS1 and spanning to 8 kyr BP with important fluctuations in environmental conditions and oxygenation. Several climate events that have been previously recognised in the Northern Hemisphere and the Mediterranean Basin can be linked to the observed changes in oxygen conditions during ORL1 deposition, for instance reoxygenation that occurred during the pre-ORL1, between the demise of Heinrich Event 1.1 (HE1.1) and the end of HS1 and the inception of the Bølling-Allerød (BA); the start of ORL1 deposition during BA with the onset of low oxygen conditions. Interestingly, the BA is punctuated by short duration reoxygenation events that can be recognised in the record and correlated to cold events observed in the North Atlantic records. In addition, there is a partial discontinuous reoxygenation during the Younger Dryas (YD), observed also in the Eastern Mediterranean and in other Mediterranean sites which was followed by the return to lower-oxygen conditions after the YD, coinciding with the start of S1 deposition. Finally, the final reoxygenation event occurs at around 8 kyr BP along with the demise of the ORL1. • A multiproxy approach has been used to reconstruct deep-sea oxygenation. • Maximum oxygen depletion marks the onset of the Deglaciation Heinrich Stadial 1 and Bølling-Allerød. • The Alboran Sea was low-ventilated during Heinrich Stadials 2 and 3 and interstadials 5 to 8. [ABSTRACT FROM AUTHOR]

The Cambrian period is an important era in geological history, marked by numerous major geological and biological events. To better understand these events, it is important to establish a high-precision chronostratigraphic framework. An astronomical time scale can be created by the identified Milankovitch cycles in well-preserved stratigraphic successions. Duibian B section in Jiangshan (Zhejiang Province, China) is the global stratotype section and point (GSSP) for the Jiangshanian Stage, and this section provides well-preserved records covering the upper Paibian to lower Jiangshanian stages. In this study, we use high-resolution magnetic susceptibility record to conduct cyclostratigraphic analysis of the Duibian B section. Our results indicate that the 2.44 m, 0.84–0.73 m, 0.20–0.19 m, and 0.12–0.09 m sedimentary cycles may represent long-eccentricity, short-eccentricity, obliquity, and precession cycles, respectively. Using the stable 405-kyr eccentricity cycles, we constructed an ∼5.96 Myr floating astronomical time scale to calibrate agnostoid trilobite zones. In addition, we reconstructed the precession rate k from geological records, and our result provides an insight into the Earth-Moon distance and length of day in the late Cambrian (Paibian–Jiangshanian, ∼494.2 Ma). It enriches our understanding of the Earth-Moon evolutionary history in deep time. • Milankovitch cycles were identified in the late Cambrian marine strata. • An ∼5.96 Myr ATS was constructed for geological events during the Paibian–Jiangshanian time. • Deep-time evolution of the Earth–Moon system was reconstructed. [ABSTRACT FROM AUTHOR]

This study explores the influence of confinement potential shape on the behavior of an off-center D0 impurity in a quantum dot (QD). In this study, we use the power exponential potential and Rashba spin-orbit interaction (RSOI), and Dresselhaus spin-orbit interaction (DSOI) beside an external magnetic field. Employing the variational method, we obtained the ground and first excited state energies and corresponding binding energies, transition energy, and magnetic susceptibilities across various impurity positions, QD parameters, and potential shapes. We ascertain the stable temperature by equating the maximum binding energy of an off-center D0 system. Subsequently, we computed the oscillator strength (OS) and conducted a comparative analysis with existing literature. Our findings demonstrate an exciting behavior in response to changes in potential shape, QD parameters, and spin-orbit coupling strengths. It helps us better understand how an off-center impurity behaves with different potential shapes in QDs and helps engineers to design devices in spintronics. [ABSTRACT FROM AUTHOR]

• Five [Qn+][Dy(β -diketonate) 4 -] n precursors were used to prepare five Dy-MOFs. • [Qn+][Dy(β -diketonate) 4 -] n was first used to control the structure of MOFs. • The change of β -diketone and Qn+ constructed different SBUs in MOFs 1 – 5. • MOFs 1 and 5 exhibit SMMs behavior. In this study, [Qn+][Dy(β -diketonate) 4 -] n (β -diketonate = Hfac, Hbtfa, Hdbm; n = 1, Q+ = Et 3 NH+, Et 4 N+; n = 2, Q2+= R -H 2 MPPA2+) was used to regulate the hydrolysis process of DyIII ions to generate different secondary building units (SBUs). The SBUs were further connected with fumaric acid ligands, exhibiting diverse coordination modes. Five dysprosium-based metal–organic frameworks (Dy-MOFs; 1 – 5) with various structural connections and topologies were synthesized. When cations in [Qn+][Dy(β -diketonate) 4 -] n were Et 3 NH+ and the anions changed from [Dy(fac) 4 ]- to [Dy(dbm) 4 ]- and [Dy(btfa) 4 ]-, three SBUs (C 2v Dy1O 8 , D 2d Dy2O 8 in 1 ; C 2v Dy1O 8 in 2 ; C 4v Dy1O 9 in 3) were formed. When anions in [Qn+][Dy(β -diketonate) 4 -] n were [Dy(btfa) 4 ]- and the cations changed from Et 3 NH+ to Et 4 N+ and R -H 2 MPPA2+, four SBUs (C 4v Dy1O 9 in 3 ; C s Dy1O 9 , D 3h Dy2O 9 in 4 ; D 4d Dy1O 8 in 5) were formed. Further magnetic characterization indicated that 2, 3 , and 4 exhibited antiferromagnetic behavior , while 1 and 5 exhibited ferromagnetic properties. The alternating-current magnetic susceptibilities of 1 and 5 exhibited significant frequency and temperature dependence. The Cole–Cole plot of 1 and 5 displayed a semicircular shape, and the effective energy barrier and relaxation time were 77.54 K and 3.20 × 10–8 s and 6.8 K and 7.50 × 10–5 s for 1 and 5 , respectively. [Display omitted] [ABSTRACT FROM AUTHOR]

• Refractory copper oxide mineral was efficiently recovered by Magnetic – Leaching process. • The acid consumption was significantly reduced by Magnetic – Leaching process compared to direct leaching. • DFT calculation revealed the copper determined the weak magnetism of copper-containing minerals. Copper oxide ore is the important component of copper resources and cannot be effectively recovered by conventional beneficiation method. In this work, the low-content and complex copper oxide ore was efficiently recovered by magnetic-leaching process. Under the optimized magnetic separation condition (feed ore size: −2 mm, rod matrix size: 3 mm, magnetic induction intensity: 1.5 T, pulsating frequency: 100 r/min), copper grade of the concentrate was enriched from 1.50 % to 8.60 % with copper recovery of 76.63 %. Compared with direct leaching, magnetic-leaching process decreased acid consumption for 1 t Cu from 13.63 t to 2.92 t. Magnetic susceptibility measurement and DFT calculation results indicated that the Cu atom of played a critical role in determining magnetism for copper-containing minerals. [ABSTRACT FROM AUTHOR]

• Industrial WLIMS and WHIMS were sampled and analyzed in terms of minerals; • Mineral recoveries are weakly correlated to their magnetic susceptibility; • Except for magnetite, mineral recoveries decrease with increasing particle size. Magnetic separation is used in ore processing to separate the minerals according to their magnetic susceptibility. Particle size also plays a role in the separation although few industrial results are presented in the literature to discuss this matter. Results from sampling industrial Wet Low Intensity Magnetic Separators (WLIMS) and Wet High Intensity Magnetic Separators (WHIMS) for processing an iron ore show that except for the strongly paramagnetic magnetite (Fe 3 O 4), the recovery of minerals decreases with increasing particle size for both WLIMS and WHIMS. The examination of polished sections of the coarse size fractions from the reject streams of the WHIMS does not provide ground to suspect liberation to be responsible for the reduced recovery of coarse particles. Results also show that it is difficult to establish clear relationships between the mineral recoveries and their reported magnetic susceptibilities for WLIMS while for WHIMS a weak trend is observable. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pollen and multiproxy studies to reconstruct palaeovegetation evolution in CGP. • Alternating climate oscillations in Late Holocene influenced Indian subcontinent. • Climate periods shaped Indian dynasties. • Last two millennia Indian Summer Monsoon pattern analysed using ESPS model. The study examines centennial-scale climatic oscillations over the past two millennia in the monsoon-dominated Indian subcontinent by multiproxy analysis of pollen along with stable carbon isotope, total organic carbon, magnetic susceptibility, and grain size from a 274 cm deep sediment profile in Sarsapukhra Lake, Varanasi, in the Central Ganga Plain (CGP) to portray vegetation changes and their impact on rise and fall of dominant dynasties. Between ∼1800 to 1600 cal yr BP, the coarser silty sand with few Poaceae and Asteraceae pollen with other proxy data, indicate that the region experienced a strong Indian Summer Monsoon (ISM). Subsequently, from ∼1600 to 1350 cal yr BP, presence of mixed moist deciduous taxa such as Shorea robusta, Madhuca indica , Rubiaceae, Morus alba , Syzygium , and Moraceae indicate a moderate ISM while between 1350 to 1200 cal yr BP, the dominance of dry deciduous taxa viz. Acacia sp., Bombax ceiba , Holoptelea , Rutaceae, Madhuca indica , Mangifera indica etc. suggested weak ISM conditions. A pulsative ameliorating trend from ∼1200 to 1030 cal yr BP showed the dominance of deciduous taxa such as Holoptelea , Rutaceae, Ziziphus , Rubiaceae, Maytenus and Acanthaceae etc. indicating warm and moist climatic conditions, followed by a weak ISM until ∼900 cal yr BP and improved ISM until 620 cal yr BP. Subsequently, an improving trend in the ISM from ∼620 to 450 cal yr BP was observed, with increased dominance of wetland taxa, followed by acute dry climate beyond ∼450 cal yr BP indicating poor ISM conditions. Additionally, the alternating warm and cold episodes had a direct impact on vegetation, forcing human civilizations to migrate from their original locations and contributing to the downfall of prominent dynasties. Furthermore, this study lays the foundation for future research into issues related to vegetation change, the amount of ISM shift, and human culture−climate relationship. [ABSTRACT FROM AUTHOR]

The Eastern Galicia Magnetic Anomaly (EGMA) is one of the most distinctive and best studied magnetic anomalies in Iberia. It is located in NW Spain and overlaps the Variscan gneissic domes of Lugo and Sanabria. The Lugo Dome, in the north of the EGMA, deforms a large thrust sheet, the Mondoñedo Nappe, allowing the outcropping of its relative autochthon in the Xistral Tectonic Window, where extensional detachments resulting from late-Variscan tectonics crop out. A younger major detachment, the Viveiro Fault, developed on the western limb of the dome. Detailed ground-based magnetic mapping and geological charts show a clear spatial relationship between magnetic maxima and the extensional structures. Magnetic and paleomagnetic studies carried out on samples from this region indicate that rocks in the detachments commonly bear magnetite and hematite carrying induced but also remanent magnetizations and a very well-defined anisotropy of the magnetic susceptibility with directions matching those of the late-Variscan extensional fabrics. Three pairs of metasedimentary samples in equivalent structural positions display variously developed medium-pressure Barrovian parageneses attributed to the early compressional phases of the Variscan orogeny, and low-pressure Buchan-type parageneses associated with the late Variscan extension. Our phase diagram-based petrological study suggests that the non-magnetic samples preserve the Barrovian conditions of 560–640 °C, 5–8.7 kbar. The lithologically and structurally equivalent samples, originally non-magnetic, developed magnetite/hematite-bearing mineral assemblages during decompression and cooling to 500–620 °C, 1.5–6 kbar. This recrystallization was probably assisted by metasomatic oxidizing fluids. The induced component of magnetization is essentially carried by magnetite, while hematite seems the main carrier of remanence. These results support the existing cartographic, geophysical and paleomagnetic findings indicating that the magnetization in the Lugo Dome is related to late-Variscan extension. [Display omitted] • The origin of the EGMA is related to late-Variscan extensional detachments. • The non-magnetic samples reflect Barrovian P-T conditions. • Magnetic samples contain low-pressure, high-temperature assemblages. • The magnetization is a result of exhumation and fluid-rock interaction. [ABSTRACT FROM AUTHOR]

Reaction of [Cu 2 (μ -L 2)(μ -O 2 CMe)]·H 2 O (1 ·H 2 O) with Et 4 NOH in MeOH medium replaces the μ -O 2 CMe bridge by MeO−. Atmospheric fixation CO 2 is achieved from nucleophilic attack of copper(II) bound MeO− to CO 2 and formation of MeOCO 2 − in [Cu 2 (μ -L 2)(μ -O 2 COMe)]·H 2 O (2 ·H 2 O). [Display omitted] • Facile synthesis of imidazolidinyl phenolate supported dicopper(II/II) complexes with multifunctional capabilities. • Dicopper(II/II) complexes serve as model systems for studying the structure. • Exhibited intriguing IR, UV–Vis, X-ray crystallographic analyses, magnetic properties, and DFT properties. • Cu 2 complex fixes atmospheric CO 2 , forming a bridging MeOCO 2 ligand, confirmed by IR spectra and crystallographic data. Two imidazolidine grafted Schiff bases H 3 L 2 and H 3 L 3 have been utilized to fasten the Cu 2 core in four new complexes [Cu 2 (μ -L 2)(μ -O 2 CMe)]·H 2 O (1 ·H 2 O), [Cu 2 (μ -L 2)(μ -O 2 COMe)]·H 2 O (2 ·H 2 O), [Cu 2 (μ -L 2)(μ -NO 3)]·H 2 O (3 ·H 2 O) and [Cu 2 L 3 (μ -OAc)]·5H 2 O (4 ·5H 2 O). Room temperature solution reaction of H 3 L 2 with Cu 2 (OAc) 4 ·2H 2 O provided 1 ·H 2 O in good yield. Follow-up reaction of 1 ·H 2 O with Et 4 NOH in air replaces μ -O 2 CMe (acetato) bridge by MeOCO 2 − (monomethyl carbonato) linker in 2 ·H 2 O. Single crystal X-ray structure established the individual complexes and confirmed the fixation of atmospheric CO 2. Variable temperature (2 to 300 K) magnetic susceptibility measurements recognized the antiferromagnetic exchange interactions between the adjacent copper(II) centers in complexes 2 and 3. The amount of spin–spin interactions are found to be higher for ancillary NO 3 − bridge (−284 cm−1) compared to the in situ transformed MeOCO 2 − bridged (−1.64 cm−1). [ABSTRACT FROM AUTHOR]

In the Northeast Mollisol region of China, straw mulching has a great effect on preventing soil loss from ridge tillage, but how furrow straw mulching (FSM) impacts the spatial distribution of erosion-deposition and sediment sources in longitudinal ridge tillage systems is still unclear. Therefore, this study was to quantify the effects of the FSM on the spatial distribution of soil erosion-deposition and sediment sources in longitudinal ridge tillage systems by using the magnetism tracing methodology and indoor simulation rainfall experiments. The experimental treatments included two surface treatments: without the FSM (NFSM) and with the FSM of 0.30 kg·m−2 amount, two rainfall intensities of 50 and 100 mm h−1 were included; each experiment was run for 60 min at a soil pan with a 5° slope gradient, 6.2 m length, 1.3 m width and 0.7 m depth. The results indicated that, compared with the NFSM treatment, the total slope runoff and soil loss in the FSM treatment at two rainfall intensities were decreased by 41.6 % and 99.5 % and by 37.9 % and 97.7 %, respectively, and the reduction in slope runoff and soil loss decreased with an increase of rainfall intensity. The total mass of sediments intercepted by straw mulching on the entire slope accounted for 36.9 % and 10.4 % of the total soil loss in the NFSM treatment, respectively. Erosion regimes dominated on the hillslope of the NFSM treatment with strong-weak alternation at two rainfall intensities, while for the FSM treatment, only deposition regime was observed at 50 mm h−1 rainfall intensity; a slight change with erosion-deposition on the ridge tops was observed and deposition in the furrows was observed at 100 mm h−1 rainfall intensity. Furthermore, the FSM treatment changed the main sediment source from ridge tops to furrows on the hillslope compared to the NFSM treatment, whose sediment contributions from the ridge tops and the furrows at the two rainfall intensities were approximately 16.4 % and 83.6 %, respectively. In conclusion, FSM should be promoted due to its high efficiency in decreasing slope runoff and intercepting sediments. The findings of this study served as a scientific reference for effectively controlling soil erosion along slopes in the Chinese Mollisol region. • The effect of straw mulch in longitudinal furrows on slope erosion was quantified. • The magnetism tracing method was used to obtain digital information on the soil loss in the longitudinal ridge system. • Furrow straw mulching weakened the hillslope spatial pattern of erosion-deposition. • The main sediment source shifted from the ridge tops to the furrows in the treatment with furrow straw mulching. [ABSTRACT FROM AUTHOR]

The magnetic properties and magnetocaloric effects of rare earth fluorides NH 4 RE 3 F 10 (RE = Tb, Dy, Ho and Er) were investigated firstly in NH 4 - RE- F system. The χ (T) curves show that the materials exhibit a paramagnetic-like behavior and high thermal reversibility. The Curie-Weiss fitting gives that there is an antiferromagnetic interaction between the magnetic moments of RE ions in these materials. Based on the magnetic isotherms data, the values of -Δ S m (T) in the cases of Δ H = 10, 20 and 50 kOe were calculated. In the case of Δ H = 10 kOe, the -Δ S m (T) of NH 4 Er 3 F 10 is the largest and the maximum value is about twice as large as that of Gd 3 Ga 5 O 12 (GGG). It indicates that the NH 4 Er 3 F 10 materials may be candidates of low-field-driven cryogenic magnetic coolant. [ABSTRACT FROM AUTHOR]

In this work, I investigated and studied the CrTe compound, which has a spin amplitude of about 2, to determine its critical behaviors at near room temperature, magnetocaloric cooling, and magnetic characteristics. For the purpose of this study, I used the Metropolis algorithm with the Monte Carlo approach. The Curie temperature of CrTe is around 326 K, which is determined through the magnetization M(T) and the inverse magnetic susceptibility (χ − 1 ). The Arrott curves (H/M vs. M2) and the isothermal magnetization M(H) demonstrate a second-order ferromagnetic (FM) to paramagnetic (PM) state phase transition. The magnetic entropy change (-ΔS M), relative cooling power (RCP), and refrigeration capacity (Q) at 8 T are 1.31 J kg⁻1 K⁻1, 106 J kg⁻1, and 79 J kg⁻1, respectively. To calculate the critical exponents of CrTe, I used the Widom scaling relation and the modified Arrott plot (MAP). The critical exponent values were found to be in good agreement with those estimated using the renormalization group approach for a 3D-Ising model. • The CrTe has been studied. • Thermal magnetization, Inverse susceptibility magnetization of the system have been established. • Transition temperature has been deduced. • Isothermal magnetic entropy change, relative cooling power (RCP) and RC for the different external magnetic field have been examined. • Critical behaviors have been determined. [ABSTRACT FROM AUTHOR]

Based on Monte Carlo Simulations (MCS) under the Metropolis algorithm, we have investigated the magnetic and magnetocaloric properties of a 2D square lattice Ising core-shell system, after discussing the exact ground state phase diagrams linked to interfacial exchange, applied magnetic field and anisotropy parameters. The obtained diagrams have exhibited various topologies depending on the model parameters. Therefore, the main quantities we have calculated are total and partial temperature-dependent magnetizations and magnetic susceptibility, as well as thermodynamic properties namely magnetic heat capacity and magnetic entropy which allowed us to evaluate the changes of entropy during magnetization and demagnetization of the system in order to measure the magnetocaloric effect (MCE). The obtained results show two types of magnetization curves which vary slightly with interfacial exchange parameter, as well as wide range of temperature where entropy change values are maximum, which is an interesting phenomenon for MCE. • Monte Carlo simulations of a 2D core-shell mixed spin (3/2, 1) system are reported. • The phase diagrams, magnetic and magnetocaloric properties are determined and discussed. • Correlation between compensation temperature and MCE is studied. • Parameters' combinations favoring maximal MCE are identified. • Potential use of our material as magnetic refrigerant is justified. [ABSTRACT FROM AUTHOR]

We report on the successful synthesis of PrCuGe 3 which crystallizes in the tetragonal BaNiSn 3 -type structure (space group: I 4 mm) with lattice parameters, a = 4.1470(2) Å and c = 10.185(3) Å. The material is characterized using dc magnetic susceptibility χ (T) , ac magnetic susceptibility χ ac (T) , isothermal magnetization M (B) , specific heat C p (T) , and electrical resistivity ρ (T) measurements. PrCuGe 3 undergoes a long-range ferromagnetic ordering at T C = 23 K, which is followed by another transition below T tr = 17 K. T C has a quite small anomaly in C p (T) and ρ (T) despite displaying large associated anomalies in both χ (T) and χ ac (T) and a sizable ferromagnetic ordered moment. Instead the transition at T tr has a much larger anomaly in C p (T) and ρ (T) but essentially no signal in χ (T) and χ ac (T). Such observations in PrCuGe 3 are nontrivial. A Sommerfeld coefficient γ = 375 mJ/(mol K2) is extracted from specific heat which indicates a significant enhancement of the quasi-particle mass at low temperature. Hence, PrCuGe 3 exemplifies a system with the coexistence of complex magnetic ordering and a putative heavy-fermion state. • Exploration of the Pr-Cu-Ge phase diagram. • PrCuGe 3 synthesis and structural considerations. • Long-range ferromagnetic ordering. • Observation of nontrivial magnetic properties. • Enhancement of quasiparticle mass. [ABSTRACT FROM AUTHOR]

Efficient outgassing of shallow magma bodies reduces the risk of explosive eruption. Silica-rich magmas are too viscous for exsolved gas bubbles to escape the system through buoyant forces alone, and so volatile overpressure is often released through deformation-related processes. Here we present a case study on magma emplacement-related deformation in a shallow (∼500 m depth) rhyolite intrusion (the Sandfell laccolith, Eastern Iceland) to investigate the establishment of degassing (volatile exsolution) and outgassing (gas escape) networks in silicic sub-volcanic intrusions. We observe viscous and brittle deformation features: from vesiculated flow bands that organized into 'pore channels' in the ductile regime, to uniform bands of tensile fractures ('fracture bands') that grade into breccia and gouge in the brittle regime. Through field mapping, structural analysis, and anisotropy of magnetic susceptibility (AMS) measurements, we show that areas with higher degrees of brittle deformation are proximal to abruptly changing AMS fabrics, and flow band orientations and point to laccolith-wide strain partitioning in the magma. We associate the changes in flow fabrics and the intensity of brittle deformation to the transition from dominantly horizontally flowing magma during initial sill-stacking to up to the NE magma flow linked to the propagation of a trap-door fault from the N to the SE. The establishment of intrusion-scale brittle permeable networks linked to changes in strain partitioning that facilitated magma flow during different stages of laccolith growth would have profoundly assisted the outgassing of the entire laccolith. Magmatic fracturing captures viscous and brittle processes working in tandem as an efficient outgassing mechanism, and should be considered in sub-volcanic intrusions elsewhere. • A viscous-brittle magmatic deformation spectrum is exposed in a rhyolite intrusion. • Densely fractured areas align with prolate fabrics reflecting laccolith growth • Fracture network allowed for outgassing during emplacement • Magma deformation preceded and controlled host rock deformation [ABSTRACT FROM AUTHOR]

Geophysical methods are widely used to gather information about the subsurface as they are non-intrusive and comparably cheap. However, the solution to the geophysical inverse problem is inherently non-unique, which introduces considerable uncertainties. As a partial remedy to this problem, independently acquired geophysical data sets can be jointly inverted to reduce ambiguities in the resulting multi-physical subsurface images. A novel cooperative inversion approach with joint minimum entropy constraints is used to create more consistent multi-physical images with sharper boundaries with respect to the single-method inversions. Here, this approach is implemented in an open-source software and its applicability on electrical resistivity tomography (ERT), seismic refraction tomography (SRT), and magnetic data is investigated. A synthetic 2D ERT and SRT data study is used to demonstrate the approach and to investigate the influence of the governing parameters. The findings showcase the advantage of the joint minimum entropy (JME) stabilizer over separate, conventional smoothness-constrained inversions. The method is then used to analyze field data from Rockeskyller Kopf, Germany. 3D ERT and magnetic data are combined and the results confirm the expected volcanic diatreme structure with improved details. The multi-physical images of both methods are consistent in some regions, as similar boundaries are produced in the resulting models. Because of its sensitivity to hydrologic conditions in the subsurface, observations suggest that the ERT method senses different structures than the magnetic method. These structures in the ERT result do not seem to be enforced on the magnetic susceptibility distribution, showcasing the flexibility of the approach. Both investigations outline the importance of a suitable parameter and reference model selection for the performance of the approach and suggest careful parameter tests prior to the joint inversion. With proper settings, the JME inversion is a promising tool for geophysical imaging, however, this work also identifies some objectives for future studies and additional research to explore and optimize the method. • Detailed review of the theory of joint minimum entropy constraints with additional considerations. • Detailed demonstration of how (joint) minimum entropy constraints influence the (joint) inversion of geophysical data. • Demonstration of approach on joint ERT-SRT inversion including a sensitivity study of important parameters. • Joint minimum entropy constrained inversion of magnetic and electrical field data to image a volcanic structure. • Discussion of factors that have significant influence on success of joint minimum entropy inversion. [ABSTRACT FROM AUTHOR]

This study investigates the metamagnetic anomaly in the Ashkin–Teller spin- 1 / 2 model in a ferromagnetic state, utilizing dynamic mean-field theory on a cubic lattice from a stochastic theory. We analyze instantaneous magnetizations over time, dynamic order parameters, and magnetic susceptibilities concerning the constant bias field, as well as examining dynamic phase diagrams. Our observations reveal that dynamic phase transitions occur at specific points of the constant bias field, where instantaneous magnetization transitions from oscillating between negative and positive states to a strictly positive state. We also observe a narrow region in the dynamic phase diagram between phase transitions of different order parameters of the model, for some conditions among the couplings of these order parameters. These results contribute to an understanding of the dynamic behavior of the spin-1/2 AT model under ferromagnetic conditions, providing interesting insights into phase transitions and the metamagnetic anomaly. • Ashkin–Teller model with constant bias magnetic field. • Phase diagram dynamics as a function of the bias magnetic field. • Dynamic order parameter with metamagnetic anomaly. • Magnetic susceptibility as a function of the bias magnetic field. • Peak of magnetic susceptibility with the metamagnetic anomaly. [ABSTRACT FROM AUTHOR]

By exploiting the Monte Carlo simulation technique, based on the Metropolis algorithm, we have investigated the mixed spin-1/2 and spin-1 Ising model in a simple cubic structure, with random magnetic field. This method was used to study phase diagrams, thermal variation of magnetizations and magnetic susceptibility, when the random field is bimodally and trimodally distribution. The results demonstrate that the system exhibits multiple qualitatively distinct types of phase diagram, depending on the values of the reduced random magnetic field H / J and the probability of distribution of this field p. When the values of the distribution probability and the reduced random field are insufficiently large, tricritical behavior manifests. Furthermore, the disorder of the system becomes difficult when the probability p is important in contrast to the random field, and the simple Ising system is found for H / J = 0 and p = 1. The values of the critical exponents associated with spontaneous magnetization and magnetic susceptibility have been well estimated and are very close to the universal values of the three-dimensional Ising model: β ≈ 0. 32218 and γ ≈ 1. 28182. • Tricritical behavior occurs for (p < 0. 35), while other cases show a purely second-order transition. • Results show a critical probability p ∗ ≈ 0. 63 , leading to two distinct critical behaviors. • For p < p ∗ , a critical H C / J value triggers a phase transition to the ground state. • If p ⩾ p ∗ , there is no H C / J , and the system retains its order at low temperatures. • Found critical exponents β ≈ 0. 32218 and γ ≈ 1. 28182 show the system's universal behavior. [ABSTRACT FROM AUTHOR]

Serpentinization, the water-driven alteration of olivine-rich rocks, is a fundamental process contributing to planetary habitability and the maintenance of rock-hosted life on Earth. Serpentinization generates molecular hydrogen via the reduction of water and the coupled oxidation of Fe, which partitions into serpentine, brucite and magnetite. Magnetite formation controls the magnetic properties of serpentinites, and researchers have highlighted a link between increasing magnetic susceptibility and decreasing density of peridotites with increasing degree of serpentinization. Several analytical and theoretical studies have suggested that these increases in magnetization and decreases in density are accompanied by increasing porosity. Here, we investigate the potential correlation between porosity generation and serpentinization by analyzing the geochemical composition, Fe redox state, and porosity of 28 abyssal serpentinites recovered via drilling from the Atlantic Ocean subseafloor. Principal component analysis applied to the resulting dataset revealed no direct links between these properties, which we suggest results from the introduction of variability due to low-temperature seafloor weathering processes. Seafloor weathering can modify the porosity of serpentinites by dissolving brucite, and it affects the Fe redox state of serpentinites by inducing the replacement of magnetite by Fe(III) minerals like maghemite, hematite, and goethite. Moreover, we also suggest that ophiolitic serpentinites would not show direct correlations between porosity and Fe redox state, due to geochemical transformations induced by metamorphism and porosity reworking linked to deformation induced by tectonic stresses. Ultimately, our results demonstrate that weathering processes can significantly affect the chemical and physical properties of serpentinites and thus must be considered in geochemical and geophysical evaluations of these rocks. • Literature studies suggest link between porosity and iron redox in serpentinites. • Porosity and geochemistry of abyssal serpentinites were characterized. • Statistical analysis revealed no significant correlations. • Correlations are obscured by seafloor weathering processes. • Characterization of full range of serpentinization could reveal hidden correlations. [ABSTRACT FROM AUTHOR]

Based on protonic-defected dicarboxylic acid, a simple pure organic single-component molecular conductor, [HEDT-TTF-dc] has been successfully synthesized. The neutral HEDT-TTF-dc molecules form two-dimensional conducting layers, which are connected by hydrogen bond interaction. The electrical resistivity measurement exhibits a semiconducting behavior with a low activation energy of 0.1 eV. The magnetic susceptibility can be fit by the singlet-triplet model, which provides with the small energy gap corresponding to the activation energy. Based on protonic-defected dicarboxylic acid, a simple pure organic single-component molecular conductor, [HEDT-TTF-dc] has been successfully synthesized. The neutral HEDT-TTF-dc molecules form two-dimensional conducting layers, which are connected by hydrogen bond interaction. The electrical resistivity measurement exhibits a semiconducting behavior with a low activation energy of 0.1 eV. The magnetic susceptibility can be fit by the singlet-triplet model, which provides with the small energy gap corresponding to the activation energy. [Display omitted] [ABSTRACT FROM AUTHOR]