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Hepatitis B virus (HBV) infection is a major health burden worldwide, and currently there is no cure. The persistence of HBV covalently closed circular DNA (cccDNA) is the major obstacle for antiviral trement. HBV core protein (HBc) has emerged as a promising antiviral target, as it plays important roles in critical steps of the viral life cycle. However, whether HBc could regulate HBV cccDNA transcription remains under debate. In this study, different approaches were used to address this question. In synthesized HBV cccDNA and HBVcircle transfection assays, lack of HBc showed no effect on transcription of HBV RNA as well as HBV surface antigen (HBsAg) production in a hepatoma cell line and primary human hepatocytes. Reconstitution of HBc did not alter the expression of cccDNA-derived HBV markers. Similar results were obtained from an in vivo mouse model harboring cccDNA. Chromatin immunoprecipitation (ChIP) or ChIP sequencing assays revealed transcription regulation of HBc-deficient cccDNA chromatin similar to that of wild-type cccDNA. Furthermore, treatment with capsid assembly modulators (CAMs) dramatically reduced extracellular HBV DNA but could not alter viral RNA and HBsAg. Our results demonstrate that HBc neither affects histone modifications and transcription factor binding of cccDNA nor directly influences cccDNA transcription. Although CAMs could reduce HBc binding to cccDNA, they do not suppress cccDNA transcriptional activity. Thus, therapeutics targeting capsid or HBc should not be expected to sufficiently reduce cccDNA transcription. IMPORTANCE Hepatitis B virus (HBV) core protein (HBc) has emerged as a promising antiviral target. However, whether HBc can regulate HBV covalently closed circular DNA (cccDNA) transcription remains elusive. This study illustrated that HBc has no effect on epigenetic regulation of cccDNA, and it does not participate in cccDNA transcription. Given that HBc is dispensable for cccDNA transcription, novel cccDNA-targeting therapeutics are needed for an HBV cure.

A simple and convenient method is demonstrated in this work by continuously applying uniaxial tensile strains to tune the high-frequency properties of flexible magnetic films. The magnetostriction effect causes the uniaxial magnetic anisotropy in the Ti/Fe/Ni81Fe19/Fe/Ti multilayer film when the flexible substrate transitions from the convex state to the planar state after preparation. In addition, the microstructure, magnetic domain morphology, and the high-frequency magnetic performance of the pre-strained Ti/Fe/Ni81Fe19/Fe/Ti multilayer films are investigated. The results show that the flexible Ti/Fe/Ni81Fe19/Fe/Ti multilayer films’ initial permeability can be monotonically varied over a hundred units, and the resonant frequency can be adjusted around 1.5 GHz. The flexible Ti/Fe/Ni81Fe19/Fe/Ti films, with their elastic-tunable magnetic performance, are promising candidate materials for flexible microwave devices.

Although substrate wettability greatly impacts deposition processes using the spin-spray technique, there are few substrates suitable for the deposition of spin-sprayed ferrite thin films. To tune substrate wettability without changing the type of substrate, we demonstrate a Ni0.17Zn0.52Fe2.31O4 ferrite film deposited by the spin-spray technique on a 0.2 mm glass substrate with 0–5% aqueous ethanol solutions. All samples showed (222) preferential orientation and triangular grain morphology. The effects of aqueous ethanol solutions on the microstructure and magnetic properties of ferrite thin films were also investigated. When the ethanol volume percent concentration equaled 3%, the columnar morphology of the microstructure was most evident and the saturation magnetization and the real permeability reached their maximum values. Because of the shape anisotropy of the columnar structure, the coercivity of the parallel magnetic field increased, whereas the coercivity of the perpendicular magnetic field decreased. First-order inversion curve measurements revealed that ethanol-containing ferrite thin films had a more uniform grain size.

M-type Sr (SrM) hexaferrites have been widely applied in millimetre/microwave ferrite devices such as circulators and isolators. SrM hexaferrites must exhibit a high remanence ratio Mr/Ms, a high anisotropy field Ha, and a low ferromagnetic resonance (FMR) linewidth ΔH to further develop millimetre/microwave equipment and devices with high frequencies, miniaturisation, and planarisation. However, it is difficult for M-type hexaferrite to simultaneously meet the requirements of high Mr/Ms, high Ha, and low ΔH, which are key to realising high-frequency self-biased ferrite devices. In this work, Ca–La–Co-substituted SrM ferrite was prepared, and the influence of La substitution on the micromorphology, static magnetic properties, and ΔH values of SrM hexaferrites is discussed in detail. The results demonstrated that as the La substitution content x increased from 0.0 to 0.5, the saturation magnetisation 4πMs and coercivity Hc initially increased, and then decreased. The Ha values of all samples were higher than 18 kOe. The FMR linewidth ΔH initially increases, and then decreased after reaching a maximum value at x = 0.2. The independent grain approximation theory was used to analyse the changing trend of the FMR linewidth. The results showed that the crystalline anisotropy linewidth ΔHa accounted for a larger proportion of the FMR linewidth than the porosity linewidth ΔHp. The sample with a La substitution content x of 0.3, exhibited the best performance (4πMs = 3915 Gs, 4πMr = 3387 Gs, Hc = 1818 Oe, Mr/Ms = 0.865, large Ha = 23.99 kOe, and ΔH = 1548 Oe at 58.8 GHz). The materials prepared in this research have significant potential for application in high-frequency self-biased devices and microwave engineering.

NiZn ferrite thin films with different compositions were prepared by spin spray deposition on an enhanced ultrasonic system and significant improvements in microstructure and magnetic properties of spin-sprayed thin-films were observed and explained. The formation of triangular grain morphology as a result of anisotropic growth was discussed based on a thin-film growth mechanism, and the preferred (222) anisotropic growth was deduced as the consequence of a uniform, fast-rate deposition of high-quality ferrite thin film by spin spray. First-order reversal curve measurement was adopted to investigate the grain size distribution of the abnormal microstructure. Moreover, a transition of magnetization mechanism took place along the increment of iron concentration which resulted in a larger permeability at high frequency. These findings provide a valuable reference for an in-depth understanding of spin spray deposition and an effective way to tune the performance of ferrite thin-film material.

Large effective magnetic anisotropy and low coercivity are usually mutually exclusive in nanometer crystalline ferrite due to opposing dependencies on the grain size. Here, by applying a parallel magnetic field during sputtering, NiZnCu ferrite thin films with larger effective magnetic anisotropy, as well as lower coercivity and an ideal permeability spectrum were prepared through adjustment of exchange length Lex. A (400) preferred orientation and a declined lattice constant triggered by the magnetic field were observed, and the cation redistribution was thoroughly discussed by XRD intensity calculation in which iron ions presented a tendency to occupy the octahedral site. By collective effects of grain growth promotion and enlarged anisotropy energy, the inducing magnetic field permitted samples with invariant stoichiometric composition a higher initial permeability and a broader working frequency range. These findings provide a valuable reference for effectively tuning magnetic properties of the magnetic thin films that are promising for high-frequency applications.

M-type hexaferrites which exhibit strong uniaxial anisotropy field, are promising for the applications in self-biased microwave and millimeter wave (MMW) devices. Here we demonstrate crystallographically textured hexaferrites with narrow ferromagnetic resonance (FMR) linewidth synthesized by the conventional ceramic method. Meanwhile, the relationship between iron-deficiency content and microstructure, crystallographic, and magnetic properties are researched. These hexaferrites have strong remanence ratio of above 0.9 along c-axis. By fitting of Lorentzian function to absorption derivative, we probe detailedly into the zero-field FMR linewidth of Ba0.8La0.2Fe11.8-xCu0.2O19-δ hexaferrites. When x equals 1.0, it indicates the narrowest FMR linewidth of 324Oe, as compared with previous reports for crystallographically textured hexaferrites.

NiCuZn (NCZ) ferrites have been widely used in non-reciprocal microwave/millimeter ferrite devices, such as circulators. With the development of microwave/millimeter devices and components to high frequency, miniaturization, and lightweight applications, NCZ ferrites have needed to satisfy the essential requirements of high saturation magnetization 4πMs, low coercivity Hc, and low ferromagnetic resonance (FMR) linewidth ΔH. Herein, 0.1 wt% Bi2O3 and 0.0–3.5 wt% CaCu3Ti4O12 (CCTO) composite additives were introduced to NCZ ferrites, the influence of Bi2O3–CCTO composite additives on micromorphology, static magnetic properties, and FMR linewidth ΔH of NCZ ferrites have been demonstrated in detail. The results show that increasing the CCTO amounts in NCZ ferrites, saturation magnetization 4πMs monotonically decreases from 5484Gs to 4819Gs, and both coercive force Hc and FMR linewidth ΔH first decreases and then increases with minimums of 31A/m and 147Oe, respectively. In addition, the theory of spin-wave narrowing and the law of approach to saturation have been adopted for the separation calculation of FMR linewidth ΔH to the crystalline anisotropy linewidth ΔHa and porosity induced linewidth ΔHp. The sample with 0.1 wt% Bi2O3 and 1.5 wt% CCTO possesses high saturation magnetization 4πMs (5321Gs), remanence Br (200 mT), low coercivity Hc (31A/m), and low FMR linewidth ΔH (147Oe). The state-of-the-art NCZ ferrites with outstanding performances manifest significant applied potency for microwave/millimeter devices and components in phase array radar systems.

MMC-HVdc transmission system has become the mainstream of power construction and plays an increasingly important role in the power system. However, the dc line fault results in shutting down of the converters, which can greatly endanger the security of the power grid. So it is essential to find a fast fault identification strategy for dc line protection technology. Besides, the existing backup protection scheme has the problems of long delay and strict communication synchronization requirements. Therefore, this paper proposes a novel protection scheme for mmc-HVdc transmission lines based on the Cross-Entropy of charge. The fault current oscillation phenomenon and fault current frequency characteristics of mmc-HVdc transmission lines are analyzed first. Secondly, this paper proposes a method to filter out distributed capacitance current by charge and eliminate the current oscillation. Finally, the difference of the charge during different faults (internal fault and external fault) is analyzed, and the Cross-Entropy is introduced to express this difference. Hence, this paper proposes a new principle of identifying faults using the Cross-Entropy of the charge. Simulation results show that the protection principle is not affected by the distributed capacitive current and does not require strict communication synchronization. It has excellent performance in intolerance to fault resistance and noise interference and can be used as backup protection for the mmc-HVdc transmission system.

Excellent gyromagnetic properties of textured, bulk Ba-hexaferrite samples are required for low-loss, self-biased applications for microwave and millimeter-wave (MMW) devices. However, conventionally processed bulk Ba-hexaferrite ceramics typically demonstrate low remanent magnetization values, 4πMr, of 2.0~3.0 kG, and relatively large ferromagnetic resonance (FMR) linewidths, ΔHFMR, of 0.8~2 kOe. These properties lead to the development of high-performance, practical devices. Herein, crystallographically textured Ba-hexaferrite samples, of the composition Ba0.8La0.2Fe11.8Cu0.2O19, having excellent functional properties, are proposed. These materials exhibit strong anisotropy fields, Ha, of ~14.6 kOe, high remanent magnetization, 4πMr, of 3.96 kGs, and a low ΔHFMR of 401 Oe at zero-bias field at the Q-band. Concomitantly, the broadband millimeter-wave transmittance was utilized to determine the complex permeability, μ*, and permittivity, ε*, of textured hexaferrites. Based on Schlöemann’s theory of complex permeability, μ*, the remanent magnetization, 4πMr, anisotropy field, Ha, and effective linewidth, ΔHeff, were estimated; these values agree well with measured values.

Highlights • MMP3 is upregulated in colon cancers. • Tumor cell-associated MMP3 expression is important for tumor growth. • The cancer therapy by MMP3 inhibition is improved together with oncolytic virus. • Downregulation of MMP3 reduces tumor cell invasion. • Erk1/2 and NF-κB signaling are changed by MMP3 downregulation., In cancer, the extracellular matrix is extensively remodeled during chronic inflammation, thus affecting cell transcription, differentiation, migration and cell-cell interactions. Matrix metalloproteinases can degrade the extracellular matrix of tumor tissues and take important roles in disease progression. Numerous efforts to develop cancer treatments targeting matrix metalloproteinases have failed in clinical trials owing to the ineffectiveness and toxicity of the applied inhibitors. In this study, we investigated the potential of targeting matrix metalloproteinases and oncolytic virus combination in cancer therapy. We found that MMP3 expression was upregulated in various cancers and MMP3 expression in the tumor cells, but not in other tissues, was important for tumor growth and metastasis. Single treatment of colon cancer with multiple MMP3 inhibitors was not effective in mice. Nevertheless, the therapeutic effect of MMP3 was greatly improved by combination with an oncolytic virus. A potential mechanism of MMP3 in regulating tumor cell proliferation and invasion was mediated via Erk1/2 an NF-κB signaling. This study reveals that MMP3 is a promising target and the combined treatment with oncolytic virus is a potential strategy for cancer therapy.

ZIKV infection can cause other severe neurological disorders, such as Guillain-Barre syndrome. Currently, more than 70 countries have reported Zika virus (ZIKV) infections, making it a global public health issue. However, there is no clinically approved vaccine available. Flaviviruses often show antigenic cross-reactivity, which can be beneficial and result in cross-protection. However, humoral cross-reactivity can also exacerbate disease via antibody-dependent enhancement (ADE). The prM-E proteins have been the primary targets of most ZIKV vaccine candidates. Therefore, to increase safety, it is necessary to investigate the use of protective ZIKV antigen for vaccine development as compared with prM-E or E protein. The capsid protein plays a crucial role in Flaviviridae biology, with a report indicating that a dengue virus vaccine engineered with a capsid protein alone produced neutralizing-antibody independent immunity and significantly reduced viral loads in the brains of challenged monkeys. In the present study, a recombinant vesicular stomatitis virus (VSV)-based vaccine carrying the ZIKV capsid protein (VSV-Capsid) was generated. VSV-capsid vaccination induced strong humoral immune response as well as cellular immune response compared with E protein based vaccine (VSV-E260-425). More importantly, the protective role was found in mice with VSV-capsid vaccination upon ZIKV infection. The viral RNA is significantly reduced in spinal cord, brain and testis of these immunized mice. Our findings demonstrated that the ZIKV capsid protein was an effective antigen in VSV vector-based delivery for ZIKV vaccine design.

Background: The global mortality rate for coronavirus disease 2019 (COVID-19) is 3.68%, but the mortality rate for critically ill patients is as high as 50%. Therefore, the exploration of prognostic predictors for patients with COVID-19 is vital for prompt clinical intervention. Our study aims to explore the predictive value of hematological parameters in the prognosis of patients with severe COVID-19. Methods: Ninety-eight patients who were diagnosed with COVID-19 at Jingzhou Central Hospital and Central Hospital of Wuhan, Hubei Province, were included in this study. Results: The median age of the patients was 59 [28-80] years; the median age of patients with a good prognosis was 56 [28-79] years, and the median age of patients with a poor outcome was 67 [35-80] years. The patients in the poor outcome group were older than the patients in the good outcome group (P

In this paper, an ISFET sensor based on In2O3 nanoribbon is developed for pH detection of micro solutions. A double channel ISFET is designed which includes the In2O3 nanoribbon top channel and silicon substrate bottom channel so as to realize the pH detection of the micro solutions. Through experiments, the sensitivity of the sensor is 70 mV/pH in the range of pH 6 to pH 10, which exceeds the Nernst limit of 59.2 mV/pH (300 K) at room temperature. Taking the detection of cTnI as an example, the pH sensor can be used to detect the concentration of biomarkers

Cardiac troponin I (cTnI) is an efficient and specific biomarker for the accurate diagnosis of acute myocardial infarction (AMI), one of the diseases with the highest mortality worldwide. Due to the short course and high fatality of this disease, a rapid, accurate and portable device for quantitative detection is urgently needed for early diagnosis and treatment. In this work, we designed a handheld device based on a dual-gate ion-sensitive field-effect transistor (ISFET) for early and accurate warning of AMI through cTnI detection. A one-step enzyme-linked immunosorbent assay strategy was proposed for use in this device to recognize trace cTnI in serum, converting the cTnI concentration to a drain-source current generated by an ultrasensitive ISFET. This portable device exhibited an ultrahigh sensitivity of 132 pA pg−1·mL−1, a wide linear range from 1 to 1000 pg/mL that enabled coverage far exceeding the threshold level (280 pg/mL), and a low detection limit of 0.3 pg/mL for the cTnI assay, which was much lower than the current diagnostic cut-off for a healthy control level for AMI (40 pg/mL). In addition, this handheld device showed satisfactory selectivity and reliable results in the analysis of real serum within 20 min, indicating its potential applications in early screening and diagnosis for the clinical evaluation of AMI.

Lead magnesium niobate–lead titanate (PMN–PT) ceramic powder and Poly[VinyliDeneFluoride-co-TriFluoroEthylene] (P[VDF–TrFE]) have been used to fabricate 0–3 composites thick films on ITO substrates by tape casting. The phase structure and grain size of PMN–PT were analyzed by XRD and SEM. The distribution of ceramic powder in polymer matrix was characterized by SEM. In order to find out the optimal poling temperature, dielectric-temperature spectrums of the composite films were measured to calculate the electric field applied to the ceramic phase (Ec). Finally, PMN–PT/P[VDF–TrFE] composite films were polarized by one-step polarization under optimized polarization temperature and their pyroelectric constant were compared with these of samples poled using conventional two-step polarization method. The results showed that the pyroelectric coefficient increases to 58.6 μC m−2 K−1 at a ceramic mass fraction of 55% at the optimized polarizing temperature 110 °C.

Calpains are calcium-activated neutral cysteine proteases. The dysregulation of calpain activity has been found to be related to cardiovascular diseases, for which calpain inhibition is used as a treatment. Viral myocarditis (VMC) is primarily caused by Coxsackievirus group B3 virus infection (CVB3). CVB3 virus infection induces autophagy and hijacks this process to facilitate its replication. In this study, we found that calpain was significantly activated in hearts affected by VMC. However, pharmacologically inhibiting calpain aggravated VMC symptoms in mice due to myocardial inflammation and cardiac dysfunction. The inhibition of calpain activity in vitro led to the accumulation of LC3-II and increased levels of p62/SQSTM1 protein expression, suggesting that autophagic flux was impaired by calpain inhibition. These effects of calpain inhibition were also observed in capn4-specific myocardial knockout mice in vivo. Furthermore, our results provided evidence that calpain inhibition in VMC, unlike other cardiovascular diseases, exacerbated the disease symptom by impairing CVB3-induced autophagic flux, which may subsequently reduce virus autolysosome degradation. Our findings indicated that calpain inhibition may not be a good treatment for VMC disease in a clinical setting.

The effect of Pb(ZrTi)0.98Mn0.02O3 (PZTM) weight ratio on the properties of PZTM/P(VDF-TrFE) pyroelectric composites and devices was reported in this paper. Infrared devices were fabricated using PZTM/P(VDF-TrFE) composite films with different weight ratio. The pyroelectric coefficient, the dielectric properties and the infrared absorptivity of the composite materials have been measured. It was found that the pyroelectric constant of the composite decreased as PZTM weight increased. In contrast, the dielectric permittivity increased as PZTM weight increased. Especially, the composite with 0.41 PZTM weight ratio showed the smallest dielectric loss and largest infrared absorptivity. The properties of the detectors fabricated using the composite materials with different PZTM weight ratio have been further tested. It was found that the infrared irradiation absorptivity showed great impact on the performance of the devices other than the pyroelectric coefficient and dielectric permittivity.

Ni0.56+x/2Zn0.34Cu0.1Fe2.0-xO4-x (x = 0, 0.02, 0.04, 0.06, 0.08, 0.12) ferrites have been prepared by the solid-state reaction method. The Rietveld refinement of X-ray diffraction patterns, microstructure, static magnetic properties and ferromagnetic resonance (FMR) linewidth of NiCuZn ferrites have been analyzed by X-ray diffraction, scanning electron microscopy (SEM), B-H analyzer and electron spin resonance (ESR) spectrometer, respectively. The FMR linewidth was investigated by an approximate calculation based on spin wave approach. The results revealed that all the samples were a single NiCuZn spinel phase. With the increase of iron-deficient amount, the lattice parameter (a) displayed a decreasing trend. However, the bulk density first increased rapidly and then trended to go up slightly. The saturation magnetization of stoichiometric NiCuZn ferrites was much lower than that of iron-deficient samples. This phenomenon is ascribed to the combined effect between molecule magnetic moment and bulk density. The magnetocrystalline anisotropy constant, derived from the law of approach to saturation, has been discussed. The anisotropy and porosity linewidth broadening models were adopted to identify the linewidth contribution. The results manifested that the porosity linewidth broadening was much larger than the anisotropy linewidth broadening.

The total energies and forces of the Ba0.5La0.5Fe11.5Cu0.5O19 structure were calculated using the density functional theory (DFT) and generalized gradient approximation (GGA). The calculations demonstrated that at 0 K, the magnetic ions Cu2+ preferentially occupy Fe3+ at the 4f2(0) and 4f2(1) configurations. For the site occupancy at the higher temperature (0–1500 K, except 0 K), we computed the formation probability of twenty inequivalent configurations using the Maxwell–Boltzmann statistical distribution. Correspondingly, the Cu2+ ions prefer to enter the 4f2 and 2b sites, especially close to lanthanum layer. In order to confirm the computational conclusions, La–Cu substituted barium hexaferrites with the chemical formula of Ba1−xLaxFe12−xCuxO19 (x = 0.0, 0.1, 0.3, and 0.5), prepared by a conventional ceramic method, were investigated by the Raman spectra and Rietveld refinement of X-ray diffraction patterns (XRD). The experiments revealed that the Cu2+ ions are partitioned at the 2b and 4f2 sites in the ratio of around 1:2.

Barium hexaferrites, which have been used to construct effective internal fields, have attracted tremendous research interest because of their potential applications in next-generation self-biased microwave and millimetre wave (MMW) devices. The lower-frequency application is currently limited by its usually strong magnetocrystalline anisotropy and large ferromagnetic resonance (FMR) linewidth. In this work, we study textured hexaferrites with excellent magnetic characteristics synthesized by the conventional ceramic method. This work uses the density-functional theory (DFT) calculations, Maxwell-Boltzmann statistical distribution, Rietveld refinements of the XRD data, and measurements of Raman spectra, to detect that scandium tends to occupy the 2a and 12k sublattices of textured hexaferrites. The zero-field FMR linewidth of textured hexaferrites is determined by the fitting of the Lorentzian function to the absorption derivative. These textured hexaferrites have a relatively narrower FMR linewidth of 482Oe than previous reports. We evaluate five critical molecular-field coefficients ωbf2, ωkf1, ωaf1, ωkf2, and ωbk of textured hexaferrites based on the Neel model of collinear-spin ferrimagnetism using nonlinear fitting methods, and the fitting results well coincide with the experimental results.

Soft magnetic composites (SMCs) are widely applied in electronic devices and components, such as inductors, as they possess the highly-saturated magnetization Ms of metallic materials and the highly-insulating characteristics of non-metals. However, with the development of electronic systems that require high-frequency operation, high-energy-transfer efficiency, and miniaturization, the suppression of core losses Pcv in their SMCs remains a considerable challenge. Herein, we explore ways to improve the frequency dependence of core losses by using various concentrations of NiZn ferrite (0.0–5.0 wt%) to coat FeSiCr magnetic powders. The microstructural, magnetic, dielectric, and core loss performances of FeSiCr@NiZn SMCs are investigated in detail. Energy dispersive X-Ray spectroscopy (EDS) mapping confirmed that the FeSiCr magnetic powders were able to be well coated with NiZn ferrite. Core loss separation method was utilized to calculate hysteresis losses Ph and eddy current losses Pe from 25 to 800 kHz at 10 mT and 25 °C. With increasing NiZn ferrite concentration, both Pcv and Ph initially decreased and subsequently increased, while Pe decreased monotonically. The sample with 3.0 wt% NiZn ferrite had the best overall performance: saturation magnetization Ms = 157 emu/g, coercive force Hc = 4.6 Oe, effective permeability μe = 60, resistivity ρ = 1.25 × 104 Ω∙m, and core losses Pcv = 38 mW/cm3 (at 800 kHz, 10 mT, and 25 °C). The excellent electromagnetic properties of these novel FeSiCr@NiZn SMCs give them enormous application potential in the fields of power transmission and conversion.

The miniaturization and integration of power conversion devices and components, such as converters and switching power supplies, require ferrite cores with high operating frequencies and temperatures. Hence, the frequency and temperature dependence of core losses is a bottleneck restricting the development of power conversion devices. Herein, nanoparticles of a dielectric material—barium titanate (BTO)—are adopted to suppress high-frequency and high-temperature core losses in MnZn ferrites. Using a loss separation method, the effects of BTO on core losses and their temperature dependence are investigated. Residual loss at 25 °C and eddy current loss at high temperatures were significantly suppressed by the addition of BTO. Remarkably, adding 0.04 wt% BTO nanoparticles resulted in MnZn ferrites with ultra-low core losses of 302 kW/m3 (25 °C) and 890 kW/m3 (100 °C) at 3 MHz and 30 mT. These superior MnZn ferrites with ultra-low core losses have potential applications in power conversion devices with high operating frequencies and temperatures. This study also provides a novel approach for suppressing core losses.

The effect of potassium-sodium niobate (KNN) powder sintering temperature on the structure and properties of the KNN/{poly(vinylidenefluoride-co-trifluoroethylene 70:30) [P(VDF-TrFE) 70:30]} composite thick films have been studied in this paper. KNN powders were sintered by solid-state reaction at different temperatures ranging from 750 to 900 °C. Then the KNN powders were used to fabricate composite thick films by casting the KNN/P(VDF-TrFE) suspension on to ITO substrates. The pyroelectric and dielectric properties of the composite thick films have been investigated systematically. It was found that sample made up of KNN ceramic powders sintered at 850 °C show optimal properties for pyroelectric appliance. The highest pyroelectric coefficient was 63 μCm−2/K and the highest detectivity figure-of-merit was 4.94 μPa1/2.