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The potential temperature is a widely used quantity in atmospheric science since it is conserved for dry air's adiabatic changes of state. Its definition involves the specific heat capacity of dry air, which is traditionally assumed as constant. However, the literature provides different values of this allegedly constant parameter, which are reviewed and discussed in this study. Furthermore, we derive the potential temperature for a temperature-dependent parameterisation of the specific heat capacity of dry air, thus providing a new reference potential temperature with a more rigorous basis. This new reference shows different values and vertical gradients, in particular in the stratosphere and above, compared to the potential temperature that assumes constant heat capacity. The application of the new reference potential temperature is discussed for computations of the Brunt-Väisälä frequency, Ertel's potential vorticity, diabatic heating rates, and for the vertical sorting of observational data.
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http://dx.doi.org/10.5194/acp-20-15585-2020 | DOI Listing |
ACS Sens
September 2025
School of Physics and Electric Engineering, Linyi University, Linyi 276000, China.
In this study, employing a 2D electrodeposition in situ assembly method, a high-performance HS sensor based on a p-n type CuO-CuFeO heterostructure ordered nanowire arrays was successfully fabricated on silicon substrates. Compared to CuO, CuO-CuFeO nanowire arrays exhibits an ideal interfacial barrier structure and higher initial resistance, with a response to 10 ppm of HS at room temperature (20 ± 3 °C) increased by 225 times and a response time reduced by over 2400 s. The sensor demonstrates exceptional sensitivity (LOD = 10 ppb; response = 234.
View Article and Find Full Text PDFACS Appl Mater Interfaces
September 2025
School of Engineering and Materials Science, Queen Mary University of London, Mile End Road, London E1 4NS, U.K.
Lead-free electroceramics have attracted significant research interest as alternatives to lead-containing systems due to concerns related to lead's toxicity to human health and the environment. Solid solutions based on bismuth sodium titanate (BNT) and barium titanate (BT), particularly those with compositions near the morphotropic phase boundary (MPB), such as 0.94 BiNaTiO-0.
View Article and Find Full Text PDFArq Bras Cardiol
September 2025
Instituto do Coração do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, SP - Brasil.
Targeted temperature management (TTM) is currently the only potentially neuroprotective intervention recommended for post-cardiac arrest care. However, there are concerns among the scientific community regarding conflicting evidence supporting this recommendation. Moreover, the bulk of trials included in systematic reviews that inform guidelines and recommendations have been conducted in developed countries, with case mix and patient characteristics that significantly differ from the reality of developing countries such as Brazil.
View Article and Find Full Text PDFJ Phys Chem Lett
September 2025
Hunan Key Laboratory of Nanophotonics and Devices, Hunan Key Laboratory of Super Microstructure and Ultrafast Process, School of Physics, Central South University, Changsha, Hunan 410083, China.
The optoelectronic properties of perovskite/two-dimensional (2D) material van der Waals heterojunctions provide greater potential for innovative neuromorphic devices. However, the traditional growth of heterojunctions still relies on strict lattice matching and high-temperature processes, which hinder high-quality interface construction and efficient carrier transport. Here, the 2D CsPbI/MoS heterojunction is realized via the van der Waals epitaxy process, overcoming lattice matching limitations.
View Article and Find Full Text PDFPhys Rev Lett
August 2025
Hokkaido University, Graduate School of Science, Sapporo 060-0810, Japan.
We have performed careful measurements of nonlinear transverse conductivity (NLTC) at zero field in the intermetallic compound HoAgGe with two distinct magnetic toroidal (MT) structures. Below 7 K (MT1 phase), the NLTC signal becomes observable and significantly increases with decreasing temperature, whereas between 7 and 11.6 K (MT2 phase), it remains nearly zero.
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