A class of multiferroic, three-phase particulate composites of Tb–Dy–Fe alloy, lead–zirconate–titanate (PZT), and polymer are investigated, in which a small volume fraction f of Tb–Dy–Fe alloy particles are dispersed in a PZT/polymer mixture. The measured dielectric, piezoelectric, and magnetoelectric properties demonstrate that a percolation transition occurs at f∼0.12 in the composites. When f is low (e.g., f<0.07), the composites exhibit piezoelectric and increasing magnetoelectric response. In the critical f range of 0.07<f<0.12, such piezo- and magnetoelectric responses sharply drop, and equal zero at the percolation threshold, above which the composite becomes a conductor and a magnetostrictive composite only.

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Multidimensional analyses have demonstrated the presence of a unique tumor microenvironment (TME) in liver cancer. Tumor‐associated macrophages (TAMs) are among the most abundant immune cells infiltrating the TME and are present at all stages of liver cancer progression, and targeting TAMs has become one of the most favored immunotherapy strategies. In addition, macrophages and liver cancer cells have distinct origins. At the early stage of liver cancer, macrophages can provide a niche for the maintenance of liver cancer stem cells. In contrast, cancer stem cells (CSCs) or poorly differentiated tumor cells are key factors modulating macrophage activation. In the present review, we first propose the origin connection between precursor macrophages and liver cancer cells. Macrophages undergo dynamic phenotypic transition during carcinogenesis. In this course of such transition, it is critical to determine the appropriate timing for therapy and block specific markers to suppress pro‐tumoral TAMs. The present review provides a more detailed discussion of transition trends of such surface markers than previous reviews. Complex crosstalk occurs between TAMs and liver cancer cells. TAMs play indispensable roles in tumor progression, angiogenesis, and autophagy due to their heterogeneity and robust plasticity. In addition, macrophages in the TME interact with other immune cells by directing cell‐to‐cell contact or secreting various effector molecules. Similarly, tumor cells combined with other immune cells can drive macrophage recruitment and polarization. Despite the latest achievements and the advancements in treatment strategies following TAMs studies, comprehensive discussions on the communication between macrophages and cancer cells or immune cells in liver cancer are currently lacking. In this review, we discussed the interactions between TAMs and liver cancer cells (from cell origin to maturation), the latest therapeutic strategies (including chimeric antigen receptor macrophages), and critical clinical trials for hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (iCCA) to provide a rationale for further clinical investigation of TAMs as a potential target for treating patients with liver cancer.

Simple multiferroic laminated ceramics of lead–zirconate–titanate PbZr0.53Ti0.47O3(PZT)/NiFe2O4 were prepared by a conventional ceramic processing. The measured magnetodielectric properties demonstrated strong dependence on the relative thickness of the PZT layers, magnetic bias, and angle between the bias and polarization in the laminated ceramics. Recent theoretical approaches were employed to explain these observed behaviors. The maximum magnetoelectric sensitivity (αE31) of the ceramics samples could reach up to as high as 0.21 V/A at 11.9 kA/m. In particular, at low magnetic bias, the laminated ceramics were found to have a very large magnetoelectric sensitivity linearly varying with the bias.

Particulate composites of lead–zirconate–titanate (PZT) and NiFe2O4 were prepared using conventional ceramic processing. The measured magnetoelectric (ME) response demonstrated strong dependence on the volume fraction of NiFe2O4, the magnetic field, and the angle between the magnetic field and polarization in the ceramics. A large ME voltage coefficient of about 80 mV cm−1 Oe−1 was observed for 0.32NiFe2O4/0.68PZT composite ceramic. In particular, at low magnetic fields, the ceramics were found to have a large ME response, linearly varying with both dc and ac magnetic fields.

Multiferroic laminated composites consisting of Terfenol-D/polyvinylidene-fluoride ͑PVDF͒ and leadzirconate titanate ͑PZT͒/PVDF particulate composite layers were prepared by a simple hot-molding technique. Magnetoelectric coefficients are characterized for the different measuring angles between the directions of polarization and applied magnetic field and at various frequencies. The results indicate that the three-phase laminated composites exhibit remarkable magnetoelectric effect especially at the resonance frequency at which the electromechanical resonance appears. The maximum magnetoelectric sensitivity of such composites is about 6 V / cm Oe at about 90 kHz.

We report on a systematic experimental investigation of a class of multiferroic, three-phase particulate composite of Tb–Dy–Fe alloy, lead–zirconate–titanate (PZT), and polymer, in which a small volume fraction f of Tb–Dy–Fe alloy particles without and with the particle surfaces modified by an inactive surfactant are dispersed in PZT/polymer mixture. The measured electrical properties demonstrate that a percolation transition occurs in the three-phase composite as in normal two-phase metal–insulator continuum media. Our piezoelectric measurements also show a percolation transition which provides an experimental test of the critical behavior of the piezoelectric composites with conductive fillers in the percolation regime. Accordingly, the multiferroic composite exhibits increasing magnetoelectric response in the low f range, but such magnetoelectric response sharply drops when f approaches the percolation threshold above which the composite becomes a conductive, magnetostrictive composite only. The inactive interface between the alloy particles and the PZT/polymer matrix induced by coating surfactant on the alloy particles produces a negative effect on the piezo- and magnetoelectric properties of the composite.

Multiferroic laminated composites consisting of lead-zirconate titanate (PZT)/polyvinylidene-fluoride (PVDF) and Tb–Dy–Fe alloy (Terfenol-D)/PVDF particulate composite layers, prepared by a simple hot-molding technique, are reported. In the laminated composites, the polymer PVDF is used just as a matrix binder. Our results demonstrate that the three-phase laminated composites exhibit remarkable magnetoelectric response especially at high frequency where an electromechanical resonance appears. The maximum magnetoelectric sensitivity of the laminated composites is as high as over 3000 mV/cm Oe at the resonance frequency of around 100 kHz.