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[Display omitted] Electromagnetic interference (EMI) shielding is critical in electronic applications. However, the currently available EMI shielding materials are restricted in customizability and application flexibility. Recent advances in manufacturing technologies have provided a unique path to achieve the custom creation of EMI shielding solutions. A successful example is additive manufacturing (AM), which has enabled high design freedom, efficient performance regulation, and multifunctionality simultaneously into fabricated shields, offering an opportunity to start a revolution in the field of EMI shielding. In this review, we summarize the latest advances in AM of EMI shielding materials, aiming to provide a deep understanding of the connection between raw materials, manufacturing methods, design considerations, and performances of the fabricated EMI shields. We first introduce the EMI shielding mechanism and available raw materials, subsequently focusing on the characteristics of representative AM methods and the as-created EMI shielding solutions. Based on the requirements to create application-oriented EMI shielding solutions, these methods are also critically compared. Thereafter, we present the state-of-the-art design considerations of EMI shields and examine the pivotal roles of AM in realizing the designs. We conclude by discussing future research directions, aiming at motivating the use of AM in the future developments of EMI shielding solutions. [ABSTRACT FROM AUTHOR]

Abstract: We used pine (Pinus elliottii Engelm.) forests located along a short urban–rural gradient in Nanchang, China to study nitrogen (N) cycling responses to urbanization. Annual average rates of nitrification and net N-mineralization in soils (0–15cm depth) measured from February 2007 to January 2009 increased from rural (8 and 37kgha−1 year−1) to suburban (69 and 79kgha−1 year−1) and urban sites (114 and 116kgha−1 year−1) (P <0.05). Soil nitrate and mineral N pools exhibited the same spatial patterns in response to urban location. In comparison to rural sites, urban and suburban sites experienced soil microbial biomass N that increased by 98% and 38%, sucrase activity that increased by 40% and 26%, and urease activity that decreased by 35% and 25%, respectively. Soil microbial biomass C:N and free amino acids varied little along the urban–rural gradient. Foliar N concentrations and N resorption proficiencies were higher in urban (12.3 and 4.8gkg−1) and suburban (12.3 and 6.2gkg−1) than in rural (9.9 and 3.6gkg−1) sites, while N resorption efficiencies (from 58% to 72%) were not statistically different. These results indicate that forests in suburban and especially in urban areas are moving rapidly towards a state of “N saturation” and increased potential N loss most likely attributable to higher N deposition to these sites. [Copyright &y& Elsevier]

Atmospheric hazardous volatile organic compounds (HVOCs) have adverse effects on human health. Health risks derived from inhalation of HVOCs have been widely assessed in Chinese cities, however, source-specific health risk analysis has been rarely done. In this work, the five intensive campaigns for monitoring HVOCs concentrations were conducted in Nanjing between July 2018 and May 2020. These datasets were further used to assess the health risks at the receptor site. The result showed that the average HVOCs concentration was 16.7 ± 20.0 ppb with higher levels in the autumn and winter. HVOCs concentrations exhibited diurnal cycles and peaked at the daytime/nighttime rush-traffic hours. By using the observed HVOCs data, the total lifetime cancer risk (LCR T) and hazard quotient (HQ T) were estimated to be 1.23 × 10−3 and 2.3, respectively, indicating the significant cancer risk and non-cancer risk at the receptor site. 1,1,2,2-tetrachloroethane (67%) was the major species to cancer risk while 1,2-dichloropropane (40%) was the dominant compound of non-cancer risk. Positive matrix factorization (PMF) model was used to resolve the source of HVOCs into vehicle emissions (29%), chemical petroleum (19%), solvent usage (17%), biomass burning (12%), coal combustion (10%), liquefied petroleum gas (9%) and fuel evaporation (4%). By combining the health risk assessments and source apportionment results, we finally concluded that solvent usage dominated both cancer risk and non-cancer risk of exposure to HVOCs at the receptor site. Thus, how to make the control measures to reduce HVOCs emissions from solvent usage will be an important issue for decreasing health risks in this polluted city. [Display omitted] • Significant cancer risk (1.23 × 10−3) and non-cancer risk (2.3) of exposure to HVOCs were found in Nanjing. • 1,1,2,2-tetrachloroethane and 1,2-dichloropropane were the major HVOCs species to health risks in Nanjing, respectively. • Solvent usage was the dominant source to 1,1,2,2-tetrachloroethane and 1,2-dichloropropane in Nanjing. • Solvent usage was the main source to health risks in Nanjing. [ABSTRACT FROM AUTHOR]