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Freezing temperature parameterization significantly impacts the heat balance at sea‐ice bottom and, consequently, the simulated sea‐ice thickness. Here, the single‐column model ICEPACK was used to investigate the impact of the freezing temperature parameterization on the simulated sea‐ice thermodynamic growth during the MOSAiC expedition from October 2019 to September 2020. It is shown that large model errors exist with the standard parameterization and that different formulations for calculating the freezing temperature impact the simulated sea‐ice thickness significantly. Considering the winter mixed layer temperature, a modified parameterization of the freezing point temperature based on Mushy scheme was developed. The mean absolute error (ratio) of simulating sea‐ice thickness for all buoys reduces from 7.4 cm (4.9%) with the "Millero" scheme, which performs the best among the existing schemes in the ICEPACK model, to 4.2 cm (2.9%) with the new developed scheme. Plain Language Summary: The heat transferred from the ocean to the sea‐ice influences the growth and melting of the sea‐ice. Freezing temperature is an essential parameter for calculating the heat transfer. Nevertheless, few studies have attempted to evaluate the impact of different freezing temperature parameterizations on the simulated sea‐ice thermodynamic growth. This study uses observed atmosphere and ocean data to force a single‐column model. Using different methods to calculate the freezing temperature significantly impacts the simulated sea‐ice thickness. After a series of testing and comparisons, we have developed a modified parameterization of freezing temperature that significantly reduces the simulation deviation from the observations. Key Points: Different parameterizations of the freezing temperature significantly influence the simulated sea‐ice thicknessA modified‐Mushy parameterization method is developed for the freezing temperature, significantly improving ice thickness simulation [ABSTRACT FROM AUTHOR]

The planetary boundary layer height (PBLH) is a crucial indicator reflecting the region of the atmosphere characterized by continuous turbulence. Here, we use radiosonde and surface meteorological observations (4–7 times per day, year‐round measurements) during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition to derive the PBLH (PBLHMOSAiC), and further evaluate the PBLH from the ERA5 reanalysis (PBLHERA5). Comparisons between PBLHMOSAiC and PBLHERA5 from different perspectives reveal that: (a) The overestimation of PBLHERA5 when the sea ice concentration is >90% is significant with the centered root mean squared error reaching up to 201 m; (b) The difference between the two products is notably pronounced in cold seasons, while it is comparatively diminished in warm seasons; (c) In neutral boundary layers, differences in PBLHERA5 are larger compared with stable and convective boundary layers. In addition, the analysis of error sources indicates that the bias of PBLHERA5 is sensitive to the bias of vertical thermal structure and wind speed profiles in ERA5 data sets in all conditions. Finally, we find a Random Forest model effectively reduces the bias of PBLHERA5 with the index of agreement reaching up to 0.71 in the test data set, while a multiple linear regression demonstrates comparable performance to the Random Forest model. Plain Language Summary: The planetary boundary layer (PBL) is a crucial component in the interactions between the atmosphere and the surface, especially for the shallow PBL in the Arctic. However, the scarcity of observations over the central Arctic limits our understanding of physical characteristics of the Arctic boundary layer, and current research relies heavily on atmospheric reanalysis. This study focuses on evaluating the planetary boundary layer height (PBLH) of ERA5 over the Arctic sea‐ice surface using observations collected during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition. We find the PBLHERA5 is often overestimated, especially with high sea ice concentrations and in cold seasons. Additionally, the PBLHERA5 performs comparatively worse against observations in neutral boundary layers when contrasted with stable and convective boundary layers. Analysis of error sources reveals the PBLHERA5 bias is sensitive to vertical thermal structure and wind speed profiles in ERA5 data sets under all conditions. To rectify the errors in the PBLHERA5, we employ a Random Forest model, significantly improving PBLHERA5's accuracy. Our model‐corrected PBLHERA5 shows strong agreement with observations, providing a more reliable representation of PBLH. This study highly enhances our understanding of the performance of the Arctic atmospheric boundary layer structure in ERA5 data sets. Key Points: The MOSAiC observations are employed to comprehensively assess the ERA5 planetary boundary layer height (PBLH) performance in the ArcticThe bias of the ERA5 PBLH is more sensitive to biases in temperature and wind speed profiles than to biases in specific humidity profileThe random forest model can reduce the ERA5 PBLH bias with the index of agreement reaching up to 0.71 in the test data set [ABSTRACT FROM AUTHOR]

Adolescents have actively looked for and passively scanned information about electronic cigarettes (e-cigarettes) from a variety of media and interpersonal sources. Despite the evidence that exposure to e-cigarette information is associated with youth's increased vaping intention, there is a paucity of scholarship that differentiates the sources where adolescents obtain e-cigarette information in their investigation, which limits our understanding of the unique association between vaping intention and e-cigarette information acquisition from specific sources. In addition, few studies have systematically examined the mechanism of the aforementioned associations. To fill the gap, an online national survey on a panel of adolescents between 13 to 17 years old was conducted. After controlling for potential confounders, several significant indirect effects were observed. Specifically, adolescents' vaping intention was negatively associated with e-cigarette information seeking from health professionals but positively with e-cigarette information exposure from family and friends, outdoors advertisements, social media, and other online channels, with the theory of planned behavior (TPB) constructs mediating these relationships. The findings not only contribute to the body of scholarship on TPB but also provide important suggestions for regulating outdoor and online e-cigarette information and designing persuasive interventions and campaigns. [ABSTRACT FROM AUTHOR]

Deep eutectic solvents (DESs), as a new type of green solvent, have shown great advantages of easy preparation, no purification needed after synthesis and great potential for application in various fields. A new type of drug delivery system called therapeutic deep eutectic solvent (THEDES) was developed when combining active pharmaceutical ingredients (APIs) into DES. Matrine has been shown great potential applications due to its anti- inflammatory, antioxidant, and antibacterial functions. This paper constructed a series of new THEDES based on matrine and fatty acids, and deeply studied the effects of alkyl chain length of fatty acids, the molar ratio of hydrogen bond donor (HBD) to hydrogen bond receptor (HBA) on the physicochemical properties of DES. The results showed that the density, surface tension, conductivity and polarity of DES declined with the increase of alkyl chain length of fatty acids, while the viscosity of DES increased with the increase of chain length of fatty acids. In addition, the density, surface tension and viscosity declined with the decrease of the molar ratio of matrine to fatty acid, while the conductivity increased with the decrease of the molar ratio of matrine to fatty acid. These different trends were due to the changes in the interaction between matrine and fatty acid molecules. The results of this work provided an important basis for the development and application of matrine-based therapeutic eutectic solvents. [ABSTRACT FROM AUTHOR]

Polyethylene oxide (PEO)-based solid polymer electrolytes (SPEs) have good ionic conductivity and flexibility, and is a key component of all-solid-state lithium batteries (ASSLBs). Therefore, the mechanical integrity of PEO-based SPEs during cell operation needs to be urgently evaluated. Here, we conducted a series of tensile and shear adhesion performance tests on PEO16–LiTFSI electrolyte and LiFePO4 electrode adhesion samples at various temperatures and quenching rates. Based on the interface performance data and the elastic–viscoplastic material model of the PEO–LiTFSI electrolyte, a comprehensive electrochemical–mechanical model was established to analyze the stress in the cell and evaluate the mechanical integrity of the PEO16–LiTFSI electrolyte and SPE/cathode interface. The experimental results show that the adhesion strength of the SPE and cathode decreases significantly with increasing operating temperature and quenching rate. The simulation study indicates that the mechanical properties of the SPE can be fully utilized to a certain extent by increasing the quenching rate. In addition, appropriately increasing the operating temperature helps maintain the mechanical integrity of the SPE during cell operation. However, increasing the quenching rate and operating temperature will reduce the interface bonding properties between the SPE and the cathode, resulting in an increased probability of mechanical failure at the SPE/cathode interface. To suppress this negative effect, a design scheme to maintain the structural integrity of the PEO-based polymer electrolyte is proposed by using the C-rate and the SPE thickness as control parameters, which can assist in engineering design and safe operation of Li/PEO16–LiTFSI/LiFePO4 for ASSLBs. [ABSTRACT FROM AUTHOR]