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Zisha stoneware is a distinctive pottery tradition unique to China. This ceramic tradition was highly popularized during the Ming Dynasty (1368–1644 CE), and continues to be manufactured through the present day. Throughout history, Zisha stoneware vessels have been highly desirable objects used mainly by high status individuals, and by the early 17th century was exported to Europe as trade items. Soon thereafter, European imitations of Zisha stonewares were produced in the Netherlands at Delft, and in England and Germany. Today, authentic Zisha wares are difficult to discern from imitations using the naked eye alone, which poses problems for provenance, authenticity of antiquities, and reconstructing ancient ceramic technologies developed in China. The goal of this study was to determine the elemental and mineralogical properties of Zisha clays and to evaluate their suitability for archaeological provenance study. This study used petrographic thin-section analysis and neutron activation analysis to characterize multiple distinct types of Zisha clays, as well as other regional clays, from deposits around Huanglong Mountain (Yixing City, China). Representative samples of each clay type were sub-divided into untreated raw clays and processed and fired ceramics for comparison. The results show clays from each major collection area have unique compositional signatures based on their trace element chemistries and mineralogical properties. Additionally, those characteristics are stable and not significantly altered by preparation or firing processes. We propose that Zisha clays have high potential for archaeological provenance studies of Zisha stoneware antiquities.

High dielectric constant polymer composites have considerable potentials in energy storage and dielectric applications because of simple fabrication process, facile processability, light-weight, excellent thermal stability and mechanical properties. Perovskite (CsPbBr3)/polyimide (PI) composites were successfully prepared via an in-situ polymerization from CsPbBr3 precursor in polyamic acid, followed by thermal imidization. The dielectric properties of polyimide composites were controlled by adjusting the content of CsPbBr3 nanocrystals. The obtained CsPbBr3/PI composites not only possess a high dielectric constant of up to 25.5 but also exhibit low dielectric loss below 0.25. The maximal discharging energy density reached up to 3.10 J cm−3 with 10% CsPbBr3, which is almost 3 times greater than pure PI under the same conditions. In addtiton, outstanding thermal properties of 5% decomposition temperature beyond 530 °C and good mechanical properties. The CsPbBr3/PI composites can be prepared facilely and rapidly on a large scale, which will be a outstanding dielectric material for high temperature polymer film capacitors.

Fabrication of high-dielectric polymer-matrix composites by adding inorganic fillers has attracted much attention, while great challenge is posed on the trade-off between enhancement of dielectric permittivity and sacrifice of mechanical flexibility. In this work, we report in-Situ formation of conductive filler strategy for making composites with significantly enhanced dielectric permittivity while well-retained mechanical flexibility. In detail, a trace amount (1.0 wt%) of graphene oxide (GO) is added into a polymer blend of polyvinylidene fluoride (PVDF) and polyacrylonitrile (PAN). After thermal annealing, the PAN and GO are simultaneously converted to conjugated structures (PCS) and reduced graphene oxide (rGO), respectively. The dielectric permittivity of resulting composites is enhanced due to the synergistic contribution between the in-Situ formed PCS and rGO conductive networks, which shows a high permittivity of 180.85 (PVDF/PCS/rGO, 20 wt% PVDF). Besides, the mechanical and thermal properties of the PVDF/PCS/rGO composites just slightly decreased owing to the trace amounts of inorganic fillers. Therefore, the prepared PVDF/PCS/rGO material with good dielectric, mechanical, and thermal property is promising flexible electronics.