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The densified MnZn ferrite ceramics were prepared using the cold sintering process under pressure, with an acetate ethanol solution used as the transient solvent. The effects of the transient solvent, the pressure and annealing temperature on the density, and the micromorphology and magnetic properties of the sintered MnZn ferrites were studied. The densified MnZn ferrite was obtained using the cold sintering process and its relative density reached up to 85.4%. The transient solvent and high pressure are essential to the cold sintering process for MnZn ferrite. The annealing treatment is indispensable in obtaining the sample with the higher density. The relative density was further increased to 97.2% for the sample annealed at 950 °C for 6 h. The increase in the annealing temperature reduces the power loss at high frequencies.

CaO2-Fe NPs are good candidates for constructing ROS ‘bomb’ with endogenous replenishment of H2O2 and depletion of GSH, achieving self-enhanced chemodynamic therapy.

Brassica juncea var. tumida (tumorous stem mustard) is widely cultivated as a feature vegetable in Ningbo, Zhejiang Province, and is used as a raw material for pickles in China. White blister rust, caused by Albugo candida, has severe negative effects on tumorous stem mustard, resulting in significant economic losses. In this study, hypha colonization and extension, haustorial formation, and the development process of sporogenous hyphae and sporangia in A. candida-infected tissues were studied using light and transmission electron microscopy. Additionally, the complex and unique sporogenous hypha developmental process was revealed. During A. candida infection, cytological and ultrastructural characteristics were similar to those of cruciferous plants. During sporogenous hyphae development, an initially cylindrical sporogenous hypha with a thin inner wall at the apex developed from a cell with a thick inner wall. At the apical end of the sporogenous hypha, an electron-dense complex gathered, causing the disintegration of the inner and outer walls and the formation of new inner and outer walls. With the formation of a clavate sporogenous hypha, a deep constriction of the cell wall occurred at its subapex, in which a septum was produced and a primary sporangium was separated from the sporogenous hypha. Both layers of the sporogenous hypha wall took part in the formation of the sporangial wall but were not related the formation of the sporangial outer wall in a septum, providing direct evidence of the holoblastic formation of sporangia. Furthermore, ultrastructural observation demonstrated that the development of the primary sporangial walls within a septum occurred later than that of their lateral walls, including the degradation of constricted outer walls around the septum, formation of the inner wall and subsequent outer walls of a sporangium in the upper septum layers, confirming the earlier observation. Therefore, this study provided the model of sporogenous hyphae development and sporangial formation in chain.

Summary Hemicycliophora species are migratory root ectoparasites of higher plants, commonly known as sheath nematodes. The present study describes a new species, Hemicycliophora geraerti n. sp., recovered from the rhizosphere of peach tree (Prunus persica) in Zhejiang Province, China. This species is characterised by a cuticular sheath loosely fitting to the body, a lip region slightly set-off with body contour bearing 3-4 annuli, oral plate narrow, ovate, and non-protruding, amphidial apertures plugged, dorsoventrally flanked in the first lip annulus, stylet 110 (103-116) μm long and flexible, excretory pore located 4-7 annuli posterior to the base of the pharyngeal bulb; vulval lips modified with a small vulval sleeve, anus located 16 (13-21) annuli posterior to vulva, tail elongated, having a narrowly rounded slightly offset spike. The molecular characterisation and phylogenetic analyses based on D2-D3 expansion segments of the 28S rRNA, ITS rRNA, and COI mtDNA gene indicated the unique status and support the novelty of this population of Hemicycliophora, therefore herein described as H. geraerti n. sp., This research was supported by the National Natural Science Foundation of China (No.31772137).

The major method used to reduce the magnetic loss of soft magnetic composites (SMCs) is to coat the magnetic powder with an insulating layer, but the permeability is usually sacrificed in the process. In order to achieve a better balance between low losses and high permeability, a novel photodecomposition method was used in this study to create a ZnO insulating layer. The effect of the concentration of diethyl zinc on the formation of a ZnO insulating film by photodecomposition was studied. The ZnO film was best formed with a diethyl zinc n-hexane solution at a concentration of around 0.40 mol/L. Combined with conventional coupling treatment processes, a thin and dense insulating layer was coated on the surface of iron powder in situ. Treating the iron powder before coating by photodecomposition led to a synergistic effect, significantly reduced core loss, and the effective permeability only decreased slightly. An iron-based soft magnetic composite with a loss value of 124 kW/m3 and an effective permeability of 107 was obtained at the frequency of 100 kHz and a magnetic field intensity of 20 mT.

High-temperature oxidation resistance of Nd–Fe–B magnetic powder is of great importance for its application in bonded magnet fields. In this work, the refinement and surface modification of Nd–Fe–B magnetic powders were integrated and achieved simultaneously. The effects of phosphoric acid, isopropyl tris-(dioctyl pyrophosphate acyloxy) titanate (ITDT), and the synergistic addition of them on the oxidation resistance of the powders were investigated. Also, the formation mechanism of the protective layer on the Nd–Fe–B powder surface has been proposed. The surface morphology, phase structure, oxidation resistance, and magnetic properties were studied. The results show that the synergistic surface modification exhibited optimal oxidation resistance on the refined magnetic powders. Furthermore, the obtained powders were bonded with polyphenylene sulfide to illustrate the effect of high-temperature oxidation resistance in practical application. The ITDT showed excellent protective performance for the magnetic properties at room temperature, whereas the phosphate showed an excellent oxidation resistance at high temperatures.

The low power loss Mn-Zn ferrites with fine grains were developed by the low-temperature-sintering ceramic process for power applications at a high frequency of 1 MHz. The LiBO2 sintering aid was added to promote the low temperature sintering and densification. The effects of LiBO2 on micromorphology and magnetic properties of the sintered Mn-Zn ferrites were investigated. With the aid of LiBO2, sintering temperature could be reduced as low as 990 °C. The optimum sample was obtained by the addition of 500 ppm LiBO2 sintered at 1020 °C. The average grain size of this sample is 2.78 μm, the density reaches 4.82 g/cm3, and the minimum power loss is 310 kW/m3 at 1 MHz/30 m T and 25 °C. This sample shows good wide-temperature stability of power loss. The mechanism of power loss affected by the LiBO2 addition was also discussed. The ceramic sintering process combining the low temperature sintering and the sintering aid offers a new way to develop high-frequency Mn-Zn ferrites.

Due to the rapid development of electronic devices towards high frequency, miniaturization, and high efficiency, it is imperative to develop MHz-frequency power ferrites exhibiting low loss over a broad temperature range. In this work, the broad-temperature low-loss Mn-Zn power ferrites operating in the frequency range of 0.5-3 MHz have been fabricated following the traditional oxide ceramic process. Co3O4 was added and its content was optimized to achieve the broad-temperature characteristics of power loss. The optimal Co3O4 content was determined to be 0.35 wt%. The power losses of this material are less than 30, 120, and 30 kW/m3 in the broad temperature range from 0 to 120 °C under the conditions of 500kHz/50 mT, 1MHz/50 mT, and 3MHz/10 mT, respectively. This material is an ideal material for applications in power conversion electronics at high frequencies (0.5-3 MHz). The effect of Co3O4 addition on power loss is discussed based on the compensation model of magnetocrystalline anisotropy constant. Analysis of the three parts of power loss reveals that the residual loss gradually becomes to be predominant above 1.2 MHz. The addition of Co3O4 reduces the residual loss and increases the cut-off frequency. This is ascribed to the induced uniaxial anisotropy of Co2+.

Ceramic injection molding is a near-net shape-processing technique, producing ceramic components with low tooling costs and complex shapes. In this paper, ZrO

Soft magnetic composites (SMC) with a bionic shell structure and a delicate, regular layered arrangement were prepared via a casting process. The permeability of composite samples was 140 at 5 MHz for plane anisotropy, while that of the spherical-particle-constructed material is only 14. According to classical loss separation results, the layered bulk material without an SiO2 coating exhibited lower hysteresis loss. In contrast, the layered bulk material coated with SiO2 showed lower eddy current loss, attributed to the increase in resistivity resulting from the SiO2 coating. The magnetic loss of the layered bulk materials was 588 kW/m3 at 50 mT and 100 kHz. SMC materials with this structure are anticipated to have strong potential for magnetic cores used in high-efficiency power supplies.

Fe-based soft magnetic composites (SMCs) co-coated with Bi2O3 and silane, used as the low melting point binder and the insulating layer, respectively, were successfully prepared. The SMCs show improved mechanical strength, thermal stability, and insulation compared to other soft magnetic composite materials. The obtained SMCs exhibit a high Bm of 1.2607 T at 5000 A/m, 50 Hz, a high μmax of 497, and a low Pcm of 81.8 W/kg at 50 kHz and 50 mT for a completely homogeneous thin insulating coating. In addition, the transverse rupture strength of such materials is up to 81.2 MPa, which is extremely important for high-speed motors. Furthermore, the permeability and magnetic loss are stable under stress. Nonlinear curve fitting was used to build the loss model and then separated into the hysteresis loss, the eddy current loss, and the excess loss. The loss mechanism of SMCs with different coatings and micro-stress was explored and verified via this model. When compared to traditional SMCs, this material coated with Bi2O3 and silane shows a lower loss and a higher transverse rupture strength. This research expands the application fields of iron-based SMCs, especially in practical applications of soft magnetic components in high-speed motors.

Chemodynamic therapy (CDT) is a booming technology that utilizes Fenton reagents to kill tumor cells by transforming intracellular H2O2 into reactive oxygen species (ROS), but insufficient endogenous H2O2 makes it difficult to attain satisfactory antitumor results. In this article, a H2O2-free CDT technique with tumor-specificity is developed by using pH-sensitive magnetic iron carbide nanoparticles (PEG/Fe2C@Fe3O4 NPs) to trigger artemisinin (ART) to in situ form ROS. ART-loaded PEG/Fe2C@Fe3O4 NPs are fabricated for the enormous release of Fe2+ ions induced by the acidic conditions of the tumor microenvironment after magnetic-assisted tumor enrichment, which results in the rapid degradation of the PEG/Fe2C@Fe3O4 NPs and release of ART once endocytosed into tumor cells. In situ catalysis reaction between the co-released Fe2+ ions and ART generates toxic ROS and then induces apoptosis of tumor cells. Both in vitro and in vivo experiments demonstrate that the efficient Fe-enhanced and tumor-specific CDT efficacy for effective tumor inhibition based on ROS generation. This work provides a new direction to improve CDT efficacy based on H2O2-independent ROS generation.

The aquatic grass Zizania latifolia grows symbiotically with the fungus Ustilago esculenta producing swollen structures called Jiaobai, widely cultivated in China. A new disease of Z. latifolia was found in Zhejiang Province, China. Initial lesions appeared on the leaf sheaths or sometimes on the leaves near the leaf sheaths. The lesions extended along the axis of the leaf shoots and formed long brown to dark brown streaks from the leaf sheath to the leaf, causing sheath rot and death of entire leaves on young plants. The pathogen was isolated and identified as the bacterium Pantoea ananatis, based on 16S ribosomal RNA (rRNA) gene sequencing, multilocus sequence analysis (atpD (β-subunit of ATP synthase F1), gyrB (DNA gyrase subunit B), infB (translation initiation factor 2), and rpoB (β‍-subunit of RNA polymerase) genes), and pathogenicity tests. Ultrastructural observations using scanning electron microscopy revealed that the bacterial cells colonized the vascular tissues in leaf sheaths, forming biofilms on the inner surface of vessel walls, and extended between vessel elements via the perforated plates. To achieve efficient detection and diagnosis of P. ananatis, species-specific primer pairs were designed and validated by testing closely related and unrelated species and diseased tissues of Z. latifolia. This is the first report of bacterial sheath rot disease of Z. latifolia caused by P. ananatis in China.

Replacement of samarium (Sm) with abundant yttrium (Y) can help solve the potential shortage of Sm in the preparation of promising Sm2Fe17Nx magnets. In this article, phase composition, microstructure and magnetic properties of (Sm1–yYy)2Fe17Nx (y = 0, 0.2, 0.4, 0.6, 0.8, 1.0) were investigated. Maximum energy product (BH)max is improved when less than 40 at% Y is doped in (Sm1–yYy)2Fe17Nx powder. In particular, when 20 at% Y replaces Sm, (BH)max of (Sm1–yYy)2Fe17Nx powder increases by 15.1% from 131.7 to 151.6 kJ/m3. The effect of annealing temperature on the structural properties of high Y doping (Sm0.6Y0.4)2Fe17 and the magnetic properties of the corresponding nitrides were subsequently investigated. In the RE2Fe17 phase grain combination process, the interlaced structure of the rhombohedral Th2Zn17-type structural phase and the hexagonal Th2Ni17-type structural phase is formed. Due to short-range exchange coupling, the nitride with the highest content of two interlaced RE2Fe17 phases has the highest magnetic properties: Br = 1.23 T, HcJ = 443.9 kA/m and (BH)max = 197.6 kJ/m3.

In this work, we prepared the nanocrystalline near-equiatomic FePt thin films by electrodeposition and explored the effects of annealing temperature and annealing time on morphology, structure, and magnetic properties of FePt film. The fcc-FePt phase starts to form when annealing at 400 °C under the 15% H2 gas mixture. With increasing annealing temperature from 400 to 800 °C, the FePt film experiences a gradual phase transformation from the soft magnetic fcc phase to the permanent magnetic fct L10 phase. The transition degree of the L10 phase is achieved to be 0.94 and coercivity reaches a maximum of 1.5 T for the sample annealed at 800 °C for 4 h. A shoulder behavior in the M(H) curves is found in the electrodeposited FePt films. Through fitting the M(H) curves by the model based on the transition degree of the L10 FePt phase, the shoulder behavior is quantitatively confirmed to originate from the coexistence of the soft magnetic fcc phase and the permanent magnetic L10 phase. The magnetic exchange coupling between the soft magnetic and permanent magnetic nanocrystalline phases is negligible in the electrodeposited FePt films due to that the substrate Ag diffusion into the FePt film separates the FePt nanocrystalline phases.

In this report, we designed and fabricated carbon-coated honeycomb microwave absorbing materials (HMAMs), which were lightweight with high stiffness and exhibited broadband performance. The effect of structural parameters such as pore size, honeycomb height, coating thickness, permittivity and dielectric dissipation factor of the coating, on the microwave absorption was analyzed in detail. An effective homogeneous model was established through the effective medium theory, which was used to predict the microwave absorption properties and elucidate the mechanism. The fabricated HMAMs showed a broadband absorption property with three absorption peaks located at 4 GHz, 10 GHz and 17 GHz with reflection loss of −10 dB, −20 dB, −25 dB, respectively. This paper not only fabricates a multiple absorbing band HMAMs, but also provides an intuitive overview of the factors affecting absorption performance of HMAMs. Additionally, the proposed method is also capable of predicting microwave absorption properties of HMAMs.

In this paper, Injection molding, debinding and sintering of ZrO2 ceramic modified by silane coupling agent (A151) were studied by measuring the melt index of feedstocks, the soluble removal ratio of green parts, the bending strength of green and sintered parts, the surface and fractural morphologies of sintered parts. The results showed that the melt index of ZrO2 feedstocks, the weight removal ratio of soluble binders, and the bending strength of green parts increased after adding A151. When the density of sintered parts was between 5.97–6.03 g/cm3, it was not the main factor influencing the bending strength. However, the bending strengths of sintered parts decreased due to microcrack formation when thermal debinding process was too fast or slow. The interesting phenomenon of the abnormal grain growth with transgranular fracture in the sintered parts obviously occurred above 1550 ℃, which made the effect of sintering temperature on the strength become complex.

During a recent inventory survey of the nematofauna of tea plantation at Zhejiang Province, China, Discocriconemella parasinensis n. sp. was detected in the rhizosphere of Camellia sinensis. The new species can be characterized by having the uninterrupted rounded labial disc, en face view showing rectangular-rounded labial plate without submedian lobes, R = 82.6 (80-86), Rex = 22 (21-23), stylet length of 68.3 (59-76) μm, excretory pore located 1-2 annuli posterior to the esophageal bulb, vulva open, postvulval body elongated conoid, and tail conoid with bilobed terminus. Morphologically, the species shares the same lip-type with D. discolabia, D. mauritiensis, D. mineira, D. perseae, and D. sinensis. Phylogenetic relationships of the new species based on D2-D3 expansion segments of 28S, ITS, and 18S rRNA genes revealed that D. parasinensis n. sp. formed a separated clade from other criconematid species, thereby supporting its status as a new species of the genus. The new species showed close phylogenetic relationships with Criconemoides geraerti., This research was supported by the National Natural Science Foundation of China (No. 31772137).