Magnetochemistry

14 pages, 2209 KB

Open AccessArticle

Synthesis, Structural, and Magnetic Properties of High-Entropy (Fe_0.2Co_0.2Cu_0.2Ni_0.2Mn_0.2)Nb₂O₆

by Maria J. S. Lima, Fernando E. S. Silva, Matheus D. Silva, Kivia F. G. Araujo, Marco A. Morales and Uílame U. Gomes

Magnetochemistry 2025, 11(11), 94; https://doi.org/10.3390/magnetochemistry11110094 (registering DOI) - 28 Oct 2025

Abstract

In this work, we present the first report on the synthesis via the sol–gel method of a high-entropy (Fe_0.2Co_0.2Cu_0.2Ni_0.2Mn_0.2)Nb₂O₆ with columbite–orthorhombic structure. Polyvinylpyrrolidone (PVP), ammonium niobium oxalate, and equimolar amounts [...] Read more.

In this work, we present the first report on the synthesis via the sol–gel method of a high-entropy (Fe_0.2Co_0.2Cu_0.2Ni_0.2Mn_0.2)Nb₂O₆ with columbite–orthorhombic structure. Polyvinylpyrrolidone (PVP), ammonium niobium oxalate, and equimolar amounts of Fe, Co, Cu, Ni, and Mn ions were used. The refinement of the XRD pattern showed the presence of niobate crystallites with an average size of 48.4 nm and a fraction of 7.6 wt% of a spinel-like phase. At temperatures below 5 K, the DC and AC magnetometry results revealed the presence of a ferromagnetic-like phase due to the niobate phase. The Mössbauer spectrum at 300 K showed a paramagnetic and two magnetically ordered components corresponding to the niobate and the spinel-like phases, respectively. The spectral components were typical of Fe³⁺, indicating the presence of cation vacancies. The elemental mapping obtained from EDS measurements showed compositional homogeneity. The XRF measurements confirmed a composition consistent with nominal values. These results confirm the feasibility of synthesizing entropy-stabilized columbite oxides via the sol–gel route, opening new opportunities for the design of multifunctional ceramics with tunable structural and magnetic properties for high-performance thermal barrier coatings and energy conversion applications. Full article

(This article belongs to the Special Issue Magnetic Materials and Composites: Synthesis, Properties, and Applications)

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16 pages, 2248 KB

Open AccessArticle

Core Loss Prediction Model of High-Frequency Sinusoidal Excitation Based on Artificial Neural Network

by Cunhao Lu, Fanjie Meng, Jiajie Zhang and Zeyuan Zhang

Magnetochemistry 2025, 11(11), 93; https://doi.org/10.3390/magnetochemistry11110093 (registering DOI) - 25 Oct 2025

Abstract

The magnitude of core loss is a crucial factor affecting the efficiency of power converters. Due to the complex mechanism of core loss, diverse influencing factors, and the strong coupling characteristics between materials and operating conditions, traditional core loss prediction models struggle to [...] Read more.

The magnitude of core loss is a crucial factor affecting the efficiency of power converters. Due to the complex mechanism of core loss, diverse influencing factors, and the strong coupling characteristics between materials and operating conditions, traditional core loss prediction models struggle to achieve high-precision prediction of core loss. Based on the Artificial Neural Network (ANN), this paper investigates core loss under high-frequency sinusoidal excitation. The core loss training data is processed using a logarithmic transformation method, and an ANN core loss prediction model is established with temperature, frequency, and magnetic flux density as features. The results show that, compared with non-logarithmic processing, logarithmic transformation of the data can effectively improve the prediction accuracy (PA) of the ANN model. Within the ±10% error range, the maximum PA of the ANN prediction model reaches 98.48%, and the minimum Mean Absolute Percentage Error (MAPE) can be as low as 2.58%. In addition, a comparison with the Steinmetz Equation (SE) and K-nearest neighbor (KNN) prediction models reveals that, for four materials, within the ±10% error range of the true core loss values, the minimum PA of the ANN model is 93.33% with an average of 95.38%; the minimum PA of the KNN model is 43.94% with an average of 62.07%; and the minimum PA of the SE model is 14.91% with an average of 19.83%. Furthermore, the MAPE of the ANN model is within 5%. Full article

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16 pages, 17336 KB

Open AccessArticle

Effect of Magnetic Field on Electrochemical Corrosion Behavior of H62 Brass Alloy

by Hexiang Huang, Dazhao Yu, Hongjun Zhao, Aiguo Gao, Yanan Li and Jiantao Qi

Magnetochemistry 2025, 11(11), 92; https://doi.org/10.3390/magnetochemistry11110092 (registering DOI) - 24 Oct 2025

Abstract

This study investigates the influence of magnetic fields on the electrochemical corrosion behavior of aerospace-grade H62 brass alloy in 3.5 wt% NaCl solution and its underlying 10 mechanisms. Employing electrochemical testing techniques combined with surface characterization methods, we explored the effects of magnetic [...] Read more.

This study investigates the influence of magnetic fields on the electrochemical corrosion behavior of aerospace-grade H62 brass alloy in 3.5 wt% NaCl solution and its underlying 10 mechanisms. Employing electrochemical testing techniques combined with surface characterization methods, we explored the effects of magnetic field intensity (25–100 mT) and orientation (parallel and perpendicular to electrode surface) on the corrosion kinetics and corrosion product evolution of H62 brass alloy. Results demonstrate that magnetic fields significantly accelerate the corrosion process of H62 brass alloy. Under parallel magnetic field (100 mT), the corrosion current density increased from 0.49 μA/cm² to 3.66 μA/cm², approximately 7.5 times that of the non-magnetic condition, while perpendicular magnetic field increased it to 1.73 μA/cm², approximately 3.5 times the baseline value. The charge transfer resistance decreased from 3382 Ω·cm² to 1335 Ω·cm². Magnetic field orientation determines the fundamental differences in corrosion acceleration mechanisms. Parallel magnetic fields primarily enhance mass transfer processes through Lorentz force-driven magnetohydrodynamic (MHD) effects, resulting in intensified uniform corrosion; perpendicular magnetic fields alter interfacial ion distribution through magnetic gradient forces, inducing localized corrosion tendencies. Magnetic fields promote the transformation of protective Cu₂O films into porous Cu₂(OH)₃Cl, reducing the protective capability of corrosion product layers. Full article

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17 pages, 1816 KB

Open AccessArticle

Investigating Magnetic Nanoparticle–Induced Field Inhomogeneity via Monte Carlo Simulation and NMR Spectroscopy

by Song Hu, Yapeng Zhang and Bin Zhang

Magnetochemistry 2025, 11(11), 91; https://doi.org/10.3390/magnetochemistry11110091 - 23 Oct 2025

Abstract

Magnetic nanoparticles (MNPs) perturb magnetic field homogeneity, influencing transverse relaxation and the full width at half maximum (FWHM) of nuclear magnetic resonance (NMR) spectra. In Nuclear Magnetic Resonance (NMR), this appears as decay of the free induction decay (FID) signal, whose relaxation rate [...] Read more.

Magnetic nanoparticles (MNPs) perturb magnetic field homogeneity, influencing transverse relaxation and the full width at half maximum (FWHM) of nuclear magnetic resonance (NMR) spectra. In Nuclear Magnetic Resonance (NMR), this appears as decay of the free induction decay (FID) signal, whose relaxation rate determines spectral FWHM. In D₂O containing MNPs, both nanoparticles and solvent molecules undergo Brownian motion and diffusion. Under a vertical main field (

B_{0}

), MNPs respond to their magnetization behavior, evolving toward a dynamic steady state in which the time-averaged distribution of local field fluctuations remains stable. The resulting spatial magnetic field can thus characterize field homogeneity. Within this framework, Monte Carlo simulations of spatial field distributions approximate the dynamic environment experienced by nuclear spins. NMR experiments confirm that increasing MNP concentration and particle size significantly broadens FWHM, while stronger

B_{0}

enhances sensitivity to MNP-induced inhomogeneities. Full article

(This article belongs to the Section Magnetic Nanospecies)

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9 pages, 7343 KB

Open AccessCommunication

Skyrmion Pair Racetrack Utilizing Hall Motion

by Shan Qiu, Tianle Zhang, Xiaotong Han, Jiahao Liu, Liang Fang and Yun Cheng

Magnetochemistry 2025, 11(10), 90; https://doi.org/10.3390/magnetochemistry11100090 - 20 Oct 2025

Abstract

The skyrmion racetrack is a promising concept for future information technology. The primary issues with skyrmion racetrack memory are now error codes and Hall motion. Here, we propose a skyrmion pair racetrack memory. The Oersted fields generated by the non-contact current-carrying wire in [...] Read more.

The skyrmion racetrack is a promising concept for future information technology. The primary issues with skyrmion racetrack memory are now error codes and Hall motion. Here, we propose a skyrmion pair racetrack memory. The Oersted fields generated by the non-contact current-carrying wire in the middle of the magnetic nanostrip stabilize the skyrmion pairs in the nanostrip, which are separated by a naturally formed domain wall. Through numerical models and micromagnetic simulations, we demonstrate that such a skyrmion pair can produce linear Hall motion along the nanostrip under the linear control of the Oersted field gradient. These findings offer a high-reliability method for skyrmion racetrack memory and a more efficient approach to designing devices that use the skyrmion Hall effect. Full article

(This article belongs to the Special Issue Magnetic Materials and Composites: Synthesis, Properties, and Applications)

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28 pages, 678 KB

Open AccessReview

Magnetic Fields as Biophysical Modulators of Anticancer Drug Action

by Xin Yu and Yue Lv

Magnetochemistry 2025, 11(10), 89; https://doi.org/10.3390/magnetochemistry11100089 - 16 Oct 2025

Abstract

Magnetic fields (MFs), including static (SMFs) and extremely low-frequency electromagnetic fields (ELF-EMFs), have recently emerged as potential modulators of anticancer drug responses. Evidence indicates that MFs can influence membrane transport, oxidative stress, DNA damage, apoptosis, and cell cycle regulation, thereby altering the efficacy [...] Read more.

Magnetic fields (MFs), including static (SMFs) and extremely low-frequency electromagnetic fields (ELF-EMFs), have recently emerged as potential modulators of anticancer drug responses. Evidence indicates that MFs can influence membrane transport, oxidative stress, DNA damage, apoptosis, and cell cycle regulation, thereby altering the efficacy of chemotherapeutics and targeted agents. These effects are strongly dependent on MFs’ parameters and biological context, leading to synergistic, antagonistic and no-effect outcomes. However, inconsistent exposure protocols, limited reproducibility, and scarce clinical validation remain major obstacles. This review highlights current experimental findings, proposes mechanistic links between MFs and drug action, and outlines key challenges for advancing MF-based adjuvant strategies in oncology. Full article

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31 pages, 12185 KB

Open AccessArticle

Artificial Neural Network-Based Heat Transfer Analysis of Sutterby Magnetohydrodynamic Nanofluid with Microorganism Effects

by Fateh Ali, Mujahid Islam, Farooq Ahmad, Muhammad Usman and Sana Ullah Asif

Magnetochemistry 2025, 11(10), 88; https://doi.org/10.3390/magnetochemistry11100088 - 10 Oct 2025

Abstract

Background: The study of non-Newtonian fluids in thin channels is crucial for advancing technologies in microfluidic systems and targeted industrial coating processes. Nanofluids, which exhibit enhanced thermal properties, are of particular interest. This paper investigates the complex flow and heat transfer characteristics of [...] Read more.

Background: The study of non-Newtonian fluids in thin channels is crucial for advancing technologies in microfluidic systems and targeted industrial coating processes. Nanofluids, which exhibit enhanced thermal properties, are of particular interest. This paper investigates the complex flow and heat transfer characteristics of a Sutterby nanofluid (SNF) within a thin channel, considering the combined effects of magnetohydrodynamics (MHD), Brownian motion, and bioconvection of microorganisms. Analyzing such systems is essential for optimizing design and performance in relevant engineering applications. Method: The governing non-linear partial differential equations (PDEs) for the flow, heat, concentration, and bioconvection are derived. Using lubrication theory and appropriate dimensionless variables, this system of PDEs is simplified into a more simplified system of ordinary differential equations (ODEs). The resulting nonlinear ODEs are solved numerically using the boundary value problem (BVP) Midrich method in Maple software to ensure accuracy. Furthermore, data for the Nusselt number, extracted from the numerical solutions, are used to train an artificial neural network (ANN) model based on the Levenberg–Marquardt algorithm. The performance and predictive capability of this ANN model are rigorously evaluated to confirm its robustness for capturing the system’s non-linear behavior. Results: The numerical solutions are analyzed to understand the variations in velocity, temperature, concentration, and microorganism profiles under the influence of various physical parameters. The results demonstrate that the non-Newtonian rheology of the Sutterby nanofluid is significantly influenced by Brownian motion, thermophoresis, bioconvection parameters, and magnetic field effects. The developed ANN model demonstrates strong predictive capability for the Nusselt number, validating its use for this complex system. These findings provide valuable insights for the design and optimization of microfluidic devices and specialized coating applications in industrial engineering. Full article

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3 pages, 158 KB

Open AccessEditorial

Advances in Soft Magnetic Materials

by Kaixuan Li and Zhaoyang Wu

Magnetochemistry 2025, 11(10), 87; https://doi.org/10.3390/magnetochemistry11100087 - 9 Oct 2025

Abstract

Soft magnetic materials have emerged as promising candidates due to their high power density in diverse magnetic components utilized for energy conversion, filtering, resonance, and isolation [...] Full article

(This article belongs to the Special Issue Advances in Soft Magnetic Materials)

17 pages, 6479 KB

Open AccessArticle

Structural Color and Mueller Matrix Analysis in a Ferrocell

by Alberto Tufaile and Adriana Pedrosa Biscaia Tufaile

Magnetochemistry 2025, 11(10), 86; https://doi.org/10.3390/magnetochemistry11100086 - 29 Sep 2025

Abstract

This study investigates the magneto-optical properties of a ferrofluid using an accessible Ferrocell device. Our findings demonstrate that the ferrofluid’s behavior is critically dependent on its concentration. At high concentrations, the medium is optically dense, with inter-particle scattering and absorption dominating, which prevents [...] Read more.

This study investigates the magneto-optical properties of a ferrofluid using an accessible Ferrocell device. Our findings demonstrate that the ferrofluid’s behavior is critically dependent on its concentration. At high concentrations, the medium is optically dense, with inter-particle scattering and absorption dominating, which prevents the formation of clear light patterns. However, with intermediate dilution, the system enters a “pattern formation zone” where the magnetic field effectively aligns the nanoparticles, creating complex, visible light patterns like horocycles. The appearance of these patterns provides evidence of field-induced ordering and structural coloration. The colors observed are not due to pigments, but result from the interaction of light with the periodic structures formed by the aligned nanoparticles. Our analysis, supported by the Mueller matrix framework, confirms that the ferrofluid acts as a retarder. The birefringence induced by the magnetic field varies across the film, leading to a chromatic dispersion that selectively suppresses certain wavelengths. This process explains how a specific color, such as blue, can be blocked at one location while others pass through, creating structural colors observed in the patterns. Full article

(This article belongs to the Special Issue Ferrofluids: Electromagnetic Properties and Applications)

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20 pages, 6572 KB

Open AccessArticle

pH and Magnetic-Responsive Carboxymethyl Chitosan/Sodium Alginate Composites for Gallic Acid Delivery

by Kun Fang, Pei Li, Hanbing Wang, Xiangrui Huang and Yihan Li

Magnetochemistry 2025, 11(10), 85; https://doi.org/10.3390/magnetochemistry11100085 - 28 Sep 2025

Abstract

Gallic acid (GA) exhibits a broad range of biological activities; however, its clinical application is significantly limited by poor stability, rapid degradation, and low bioavailability. Consequently, developing responsive delivery platforms to enhance GA stability and targeted release has become an important research focus. [...] Read more.

Gallic acid (GA) exhibits a broad range of biological activities; however, its clinical application is significantly limited by poor stability, rapid degradation, and low bioavailability. Consequently, developing responsive delivery platforms to enhance GA stability and targeted release has become an important research focus. Herein, GA was encapsulated within novel composite hydrogel beads (CMC-SA-Fe₃O₄@GA) prepared via crosslinking carboxymethyl chitosan (CMC) and sodium alginate (SA) with Fe₃O₄ nanoparticles (NPs) to facilitate efficient drug delivery. The formulation was characterized and evaluated in terms of drug-loading capacity, controlled-release properties, antioxidant activity, antibacterial performance, and biocompatibility. The results indicated that the GA loading efficiency reached 31.07 ± 1.23%. Application of an external magnetic field accelerated GA release, with the observed release kinetics fitting the Ritger–Peppas model. Furthermore, antioxidant capacity, evaluated by DPPH assays, demonstrated excellent antioxidant activity of the CMC-SA-Fe₃O₄@GA composite beads. Antibacterial tests confirmed sustained inhibitory effects against Escherichia coli and Staphylococcus aureus. In vitro, cellular assays indicated favorable biocompatibility with normal hepatic cells (HL-7702) and effective inhibition of hepatocellular carcinoma cells (HepG2). Overall, the novel pH- and magnetic field-responsive CMC-SA-Fe₃O₄@GA hydrogel system developed in this work offers considerable potential for controlled delivery of phenolic compounds, demonstrating promising applicability in biomedical and food-related fields. Full article

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17 pages, 4644 KB

Open AccessArticle

Study of the Magnetohydrodynamic Instability and a New Suppression Method in Liquid Metal Batteries

by Jia-Jun Song, Xiao-Zhong Zuo, En-Qi Zhu, Qi-Guang Li, Bao-Zhi Chen and Ben-Wen Li

Magnetochemistry 2025, 11(10), 84; https://doi.org/10.3390/magnetochemistry11100084 - 25 Sep 2025

Abstract

As a strong candidate for energy storage applications, Liquid Metal Batteries (LMBs) have the advantages of higher current density, longer cycle life, and simpler manufacturing of large-scale storage systems. Owing to the all-liquid construction, various kinds of Magnetohydrodynamic instabilities (MHDIs) are present in [...] Read more.

As a strong candidate for energy storage applications, Liquid Metal Batteries (LMBs) have the advantages of higher current density, longer cycle life, and simpler manufacturing of large-scale storage systems. Owing to the all-liquid construction, various kinds of Magnetohydrodynamic instabilities (MHDIs) are present in LMBs. In this paper, an in-depth study of the evolution process of MHDIs within LMBs has been conducted. By analyzing the characteristic velocity, the growth rate of instabilities γ has been defined so that the critical Hartmann number at which the instability occurs can be ascertained. A new critical parameter, mixed Reynolds number Re_mix, has been introduced to determine the duration of stable battery operation across varying charging/discharging currents, including those that may surpass the prescribed safe limits. Finally, a method for mitigating magnetohydrodynamic instability in LMBs through the configuration of busbar current is proposed, which can be seamlessly integrated with parallel battery packs. A comparative analysis of LMBs operation with/without bus current configuration reveals that when bus current is appropriately configured, the magnetic field strength within the battery undergoes a notable reduction of 40%, leading to a significant suppression of instability. The conclusions offer theoretical underpinnings for the application of LMBs in large-scale grid-level energy storage systems. Full article

(This article belongs to the Section Magnetic Field)

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21 pages, 6518 KB

Open AccessArticle

Topological Rainbow Trapping in One-Dimensional Magnetoelastic Phononic Crystal Slabs

by Wen Xiao, Fuhao Sui, Jiujiu Chen, Hongbo Huang and Tao Luo

Magnetochemistry 2025, 11(10), 83; https://doi.org/10.3390/magnetochemistry11100083 - 25 Sep 2025

Abstract

We design a one-dimensional magnetoelastic phononic crystal slab composed of the smart magnetostrictive material Terfenol-D and pure tungsten. Band inversion and topological phase transitions are achieved by modifying the geometric parameters of the non-magnetic medium within the unit cell. The emergence of topological [...] Read more.

We design a one-dimensional magnetoelastic phononic crystal slab composed of the smart magnetostrictive material Terfenol-D and pure tungsten. Band inversion and topological phase transitions are achieved by modifying the geometric parameters of the non-magnetic medium within the unit cell. The emergence of topological interface states within overlapping bandgaps, exhibiting distinct topological properties, along with their robustness against interfacial structural defects, is confirmed. The coupling effects between adjacent topological interface states in a sandwich-like supercell configuration are investigated, and their tunability under external magnetic fields is demonstrated. A Su-Schrieffer-Heeger (SSH) phononic crystal slab system under gradient magnetic fields is proposed. Critically, and in stark contrast to previous static or structurally graded designs, we achieve reconfigurable rainbow trapping of topological interface states solely by reprogramming the gradient magnetic field, leaving the physical structure entirely unchanged. This highly localized, compact, and broadband-tunable topological rainbow trapping system design holds significant promise for applications in elastic energy harvesting, wave filtering, and multi-frequency signal processing. Full article

(This article belongs to the Special Issue Advances in Low-Dimensional Magnetic Materials)

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25 pages, 4694 KB

Open AccessReview

Magnetic-Responsive Material-Mediated Magnetic Stimulation for Tissue Engineering

by Jiayu Gu, Lijuan Gui, Dixin Yan, Xunrong Xia, Zhuoli Xie and Le Xue

Magnetochemistry 2025, 11(10), 82; https://doi.org/10.3390/magnetochemistry11100082 - 23 Sep 2025

Abstract

Tissue repair is a significant challenge in biomedical research. Traditional treatments face limitations such as donor shortage, high costs, and immune rejection. Recently, magnetic-responsive materials, particularly magnetic nanoparticles have been introduced into tissue engineering due to their ability to respond to external magnetic [...] Read more.

Tissue repair is a significant challenge in biomedical research. Traditional treatments face limitations such as donor shortage, high costs, and immune rejection. Recently, magnetic-responsive materials, particularly magnetic nanoparticles have been introduced into tissue engineering due to their ability to respond to external magnetic fields, generating electrical, thermal, and mechanical effects. These effects enable precise regulation of cellular behavior and promote tissue regeneration. Compared to traditional physical stimulation, magnetic-responsive material-mediated stimulation offers advantages such as non-invasiveness, deep tissue penetration, and high spatiotemporal precision. This review summarizes the classification, fabrication, magnetic effects and applications of magnetic-responsive materials, focusing on their mechanisms and therapeutic effects in neural and bone tissue engineering, and discusses future directions. Full article

(This article belongs to the Section Applications of Magnetism and Magnetic Materials)

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4 pages, 1311 KB

Open AccessEditorial

Magnetic Nanospecies: Synthesis, Properties, Physical and Biomedical Applications

by Alexey Chubarov

Magnetochemistry 2025, 11(9), 81; https://doi.org/10.3390/magnetochemistry11090081 - 22 Sep 2025

Abstract

Magnetic nanoparticles and nanocomposites continue to garner considerable interest due to their versatility in biomedical applications, ranging from diagnostics and therapy to catalysis and sensing [...] Full article

(This article belongs to the Special Issue Magnetic Nanospecies: Synthesis, Properties, Physical and Biomedical Applications)

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16 pages, 6028 KB

Open AccessArticle

Parahydrogen-Based Hyperpolarization for the Masses at Millitesla Fields

by Garrett L. Wibbels, Clementinah Oladun, Tanner Y. O’Hara, Isaiah Adelabu, Joshua E. Robinson, Firoz Ahmed, Zachary T. Bender, Anna Samoilenko, Joseph Gyesi, Larisa M. Kovtunova, Oleg G. Salnikov, Igor V. Koptyug, Boyd M. Goodson, W. Michael Snow, Eduard Y. Chekmenev and Roman V. Shchepin

Magnetochemistry 2025, 11(9), 80; https://doi.org/10.3390/magnetochemistry11090080 - 22 Sep 2025

Cited by 1

Abstract

Hyperpolarization (HP) techniques, such as Parahydrogen-Induced Polarization (PHIP), Signal Amplification by Reversible Exchange (SABRE), and dissolution Dynamic Nuclear Polarization (d-DNP), significantly enhance the sensitivity of nuclear magnetic resonance (NMR) spectroscopy for chemical analysis and metabolic imaging. However, the high cost of equipment, ranging [...] Read more.

Hyperpolarization (HP) techniques, such as Parahydrogen-Induced Polarization (PHIP), Signal Amplification by Reversible Exchange (SABRE), and dissolution Dynamic Nuclear Polarization (d-DNP), significantly enhance the sensitivity of nuclear magnetic resonance (NMR) spectroscopy for chemical analysis and metabolic imaging. However, the high cost of equipment, ranging from tens of thousands to millions of dollars, limits accessibility of hyperpolarization for the broad scientific community. In this work, we aim to mitigate some of the challenges by developing a cost-effective solution for parahydrogen (pH₂)-based PHIP and SABRE HP methods. A custom coil-winding machine was designed to fabricate solenoid magnet coils, which were then evaluated for their magnetic field profiles, demonstrating a high degree of magnetic field homogeneity. A model ¹H SABRE experiment successfully implemented the constructed solenoid, achieving efficient hyperpolarization. Additionally, the solenoid magnet can be utilized for in situ detection of hyperpolarization when integrated with a low-field NMR spectrometer, reducing the total setup cost to a few thousand dollars. These findings suggest that our approach makes HP technology more affordable and accessible, potentially broadening its applications in chemical and biomedical research, as well as educational settings involving undergraduate student researchers. This work provides a practical pathway to lower the financial barriers associated with pH₂ HP setups. Full article

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15 pages, 2106 KB

Open AccessArticle

Quantitative Analysis of the Components of Rotigotine Prolonged-Release Microspheres for Injection Using Solvent-Suppressed ¹H NMR

by Xiaoli Zhou, Zengxin Li, Xue Ni, Wanhui Liu and Lihui Yin

Magnetochemistry 2025, 11(9), 79; https://doi.org/10.3390/magnetochemistry11090079 - 4 Sep 2025

Abstract

We developed a solvent-suppressed ¹H nuclear magnetic resonance (NMR) method for the quantitative analysis of the components of rotigotine prolonged-release microspheres prepared for injection. Dimethyl terephthalate was used as an internal standard and dimethylsulfoxide -d₆ as the solvent. The analysis [...] Read more.

We developed a solvent-suppressed ¹H nuclear magnetic resonance (NMR) method for the quantitative analysis of the components of rotigotine prolonged-release microspheres prepared for injection. Dimethyl terephthalate was used as an internal standard and dimethylsulfoxide -d₆ as the solvent. The analysis was performed using a Bruker Avance III HD 600 MHz NMR spectrometer, employing the noesygppr1d pulse sequence at a controlled temperature of 25 °C. Nuclear magnetic resonance spectra were acquired with a relaxation delay time (D1) of 40 s to simultaneously determine the content of rotigotine and the excipients mannitol and stearic acid in the rotigotine prolonged-release microspheres. Using the proposed approach, we successfully quantified the active pharmaceutical ingredient rotigotine and excipients in the prolonged-release microspheres. This method demonstrated excellent linearity, high precision, and strong repeatability. The solvent-suppressed ¹H NMR method developed in this study allows for the simultaneous quantification of rotigotine and the key excipients mannitol and stearic acid in the prolonged-release microspheres. This approach is accurate, simple, efficient, and environmentally friendly. Full article

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12 pages, 3515 KB

Open AccessArticle

Magnetic Properties and Coercivity Mechanism of Nanocrystalline Rare-Earth-Free Co₇₄Zr₁₆Mo₄Si₃B₃ Alloys

by Aida Miranda and Israel Betancourt

Magnetochemistry 2025, 11(9), 78; https://doi.org/10.3390/magnetochemistry11090078 - 2 Sep 2025

Abstract

The microstructure and magnetic properties of rare-earth-free, melt-spun Co₇₄Zr₁₆Mo₄Si₃B₃ alloys were investigated to enhance their hard magnetic response and elucidate their coercivity mechanism. The alloys exhibit a polycrystalline microstructure composed of randomly oriented, equiaxed [...] Read more.

The microstructure and magnetic properties of rare-earth-free, melt-spun Co₇₄Zr₁₆Mo₄Si₃B₃ alloys were investigated to enhance their hard magnetic response and elucidate their coercivity mechanism. The alloys exhibit a polycrystalline microstructure composed of randomly oriented, equiaxed grains, predominantly comprising the rhombohedral hard magnetic Co₁₁Zr₂ phase (92.4 wt.%). These materials display a favorable combination of magnetic properties, with coercive fields up to 581 kA/m, maximum magnetization reaching 0.30 T, and Curie temperatures as high as 751 K. An interpretation of the results, based on microstructural features, intrinsic magnetic parameters, and micromagnetic simulations, indicates that the coercivity mechanism of these melt-spun alloys can be attributed to the nucleation of reverse magnetic domains. Full article

(This article belongs to the Section Magnetic Materials)

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26 pages, 10898 KB

Open AccessReview

Molecular Nanomagnets with Photomagnetic Properties: Design Strategies and Recent Advances

by Xiaoshuang Gou, Xinyu Sun, Peng Cheng and Wei Shi

Magnetochemistry 2025, 11(9), 77; https://doi.org/10.3390/magnetochemistry11090077 - 31 Aug 2025

Abstract

The magnetic properties of molecular nanomagnets can be finely modulated by light, which provides great potential in optical switches, smart sensors, and data storage devices. Light-induced spin transition, structure changes, and radical formation could tune the static and dynamic magnetic properties of molecular [...] Read more.

The magnetic properties of molecular nanomagnets can be finely modulated by light, which provides great potential in optical switches, smart sensors, and data storage devices. Light-induced spin transition, structure changes, and radical formation could tune the static and dynamic magnetic properties of molecular nanomagnets with high spatial and temporal resolutions. Herein, we summarize the design strategies of photoresponsive molecular nanomagnets and review the recent advances in transition metal/lanthanide molecular nanomagnets with photomagnetic properties. The photoresponsive mechanism based on spin transition, photocyclization, and photogenerated radicals is discussed in detail, providing insights into the photomagnetic properties of molecular nanomagnets for advanced photoresponsive materials. Full article

(This article belongs to the Special Issue Molecular Magnetism: A Themed Issue in Honor of Professor Dai-Zheng Liao on the Occasion of His 85th Birthday)

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5 pages, 172 KB

Open AccessEditorial

Advances in Functional Magnetic Nanomaterials for Water Pollution Control

by Wei Ding and Huaili Zheng

Magnetochemistry 2025, 11(9), 76; https://doi.org/10.3390/magnetochemistry11090076 - 27 Aug 2025

Cited by 1

Abstract

The application of magnetism in water treatment processes has enhanced efficiency across various stages, including coagulation, flocculation, sedimentation, and filtration, representing a field with significant potential [...] Full article

(This article belongs to the Special Issue Applications of Magnetic Materials in Water Treatment)

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