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Electrical resistivity method has been widely used to study permafrost and to monitor the process of freezing-thawing. However, a thorough understanding of the mechanism of electrical response during thawing is missing. In this study, we investigated the thawing behavior of saline soils in the temperature range from roughly −10 to 15°C considering the effects of soil type and salinity. A total of nine experiments were performed with three soil types (silica sand, sandy soil, and silt) and three salinities (0.01, 0.1, and 1 S m−1). The results show that resistivity variations with temperature can be divided into three stages. In Stage I, tortuosity and unfrozen water content play major roles in the decrease of resistivity. In Stage Ⅱ, which is an isothermal or near isothermal process, resistivity still decreases slightly due to the thawing of residual ice and pore water movement. In Stage III, ionic mobility plays an important impact on decreasing resistivity. In addition, the isothermal process is found to only occur in silica sand that can be explained by latent heat effect. Exponential and linear models linking temperature with resistivity are used to fit the experimental data in Stages I and III. The fitting parameter in different models shows great correlation with soil type and salinity. Furthermore, unfrozen water content below 0°C is also estimated and uncertainty of estimation is analyzed. [ABSTRACT FROM AUTHOR]

Developing p-type oxide thin-film transistors (TFTs) is an essential path for further application in complementary metal oxide semiconductor (CMOS) components. However, the inferior electrical performance of p-type MO TFTs compared to n-type TFTs remains an ongoing challenge. Herein, for the first time, a low temperature, facile material engineering approach by incorporating n-type nanoparticles (NPs) was proposed for preparing p-type transparent NiOx TFTs. The characteristics of thin films blending NPs and the electrical performances of TFTs were investigated. The field effect mobility of TFTs with doping was nearly 20 times higher than pristine TFTs without doping, which was mainly beneficial from the suitable band alignment between NPs and p-type oxide, the increasing Ni3+ oxidation state in NiOx, as well as the improved dielectric/semiconductor interface quality. Electrons from drain electrode injected into metal oxide turn accepted in NPs rather than being trapped in the dielectric/semiconductor interface due to a strong surface electron depletion effect of NPs. NPs with small particle size and appropriate concentration would promote continuous hole transport by electrons transferring and reducing the interface trap state. The facile material engineering strategy is a promising technique for preparing p-type transparent MO-TFTs at low temperature, which showed great potential to be applicable in CMOS circuits on flexible substrates. [ABSTRACT FROM AUTHOR]