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Bismuth sodium titanate (BNT)-based, lead-free piezoelectric materials have been extensively studied due to their excellent strain characteristics and environmental friendliness. In BNTs, the large strain (S) usually requires a relatively large electric field (E) excitation, resulting in a low inverse piezoelectric coefficient d33* (S/E). Moreover, the hysteresis and fatigue of strain in these materials have also been bottlenecks impeding the applications. The current common regulation method is chemical modification, which mainly focuses on forming a solid solution near the morphotropic phase boundary (MPB) by adjusting the phase transition temperature of the materials, such as BNT-BaTiO3, BNT-Bi0.5K0.5TiO3, etc., to obtain a large strain. Additionally, the strain regulation based on the defects introduced by the acceptor, donor, or equivalent dopant or the nonstoichiometry has proven effective, but its underlying mechanism is still ambiguous. In this paper, we review the generation of strain and then discuss it from the domain, volume, and boundary effect perspectives to understand the defect dipole behavior. The asymmetric effect caused by the coupling between defect dipole polarization and ferroelectric spontaneous polarization is expounded. Moreover, the defect effect on the conductive and fatigue properties of BNT-based solid solutions is described, which will affect the strain characteristics. The optimization approach is appropriately evaluated while there are still challenges in the full understanding of the defect dipoles and their strain output, in which further efforts are needed to achieve new breakthroughs in atomic-level insight.

As plastic products are widely used in all walks of life, plastic waste is also accumulating in the environment. Today, microplastic pollution in the soil environment has become an environmental issue of global concern. Compared with the water environment, the research on microplastics in the soil environment is relatively lacking. Based on the above situation, this paper systematically reviews the distribution characteristics, influencing factors, and environmental and ecological risks of microplastics in the soil environment. The abundance, distribution characteristics, and impacts of microplastics in soils globally in recent years are reviewed in detail. Our review suggests that most scholars only focus on the surface soil, and the determination of the accumulation of microplastics in the soil as a whole is still lacking, and there is still no uniform standard for sampling techniques, extraction methods, analytical procedures, and even expression units for soil microplastics. The distribution of microplastics in soil is affected by human factors, natural factors, and the physical and chemical properties of the plastics themselves. We also focused on the analysis of the environmental risks arising from the accumulation of microplastics in soil interacting with metals and organic pollutants, and found that large research gaps exist in the interaction between microplastics and pollutants in the soil and the mechanism of compound pollution. The impact and ecological risks of microplastics on animals, microorganisms, and plants in the soil are explained. Moreover, key suggestions for future research are presented based on the current research status, and we call for more efforts focusing on the occurrence and fate of microplastics in the soil environment.

Climate change and urbanization are causing increasingly frequent urban flooding in countries around the world. Various innovative approaches have emerged to address this challenge. In China, the Sponge City was first proposed in 2012 to achieve an urban hydrological balance through natural storage, natural infiltration and natural purification. This article presents a comparative investigation (using a survey method) of new and old communities in Xixian New District and Xi’an in September 2021 to investigate public awareness of the Sponge City and understand levels of satisfaction and acceptance. Individuals of the same age or education residing in the Sponge City generally know more about the Sponge City and were more willing to accept it than those in traditional cities. Moreover, the residents of Sponge City understand the Sponge City concept well, with a majority of the respondents (71.82%) expressing clear understanding on the conception of Sponge City. However, residents in a traditional city exhibited much less understanding of the concept (44.24%). Furthermore, for those living in the same area, people who are younger or have higher education exhibited a clearer understanding of and acceptance of the Sponge City and local government. In this survey, the average scores (assign values to the different responses, then average and percent it) of respondents in Xixian New District with master’s degrees, bachelor’s degrees and high school degrees or below were evaluated at 76.88, 67.94 and 62.15, respectively, compared to 62.07, 50.18 and 50.78 in Xi’an. Lastly, we found that differences in living environment have a significant influence on residents’ perceptions. Residents living in the Sponge City are generally satisfied with the travel and living conditions and greatly support the local government. Meanwhile, this study will help relevant authorities pay more attention to residents’ opinions and help them to formulate policies to spread the concept of Sponge City and encourage residents’ participation.

The energy audit&mdash, an assessment of a home&rsquo, s energy systems performed by a trained auditor in order to provide the resident with strategies for saving energy and money&mdash, is provided by many utility companies throughout the United States for free or at a reduced cost. The uptake of such programs is generally low, and little is known about audit participants. Importantly, as more evidence points to the need to look beyond physical building characteristics to increase energy efficiency, this work explores if specific characteristics of the individual are correlated with increased participation in audit programs. This research analyzes the most recent (2015) national level Residential Energy Consumption Survey (RECS) data through a binary logit regression to determine what socioeconomic and demographic factors, if any, are statistically significant in linking to the decision to undertake an audit, while controlling for physical building characteristics. The findings indicate that age has a significant and positive relationship with the decision to undertake an audit, as does being non-white, while renting has a significant and negative relationship. Knowledge about national-level participation in audit programs can help policy makers craft more strategic incentives to increase participation and, ultimately, help connect the audit decision to the more important next step of retrofits and upgrades to save energy.