Nanowires of bismuth antimony telluride and bismuth telluride selenide (Bi15Sb29Te56 and Bi38Te55Se7) were grown by template-based pulsed electrodeposition. The composition and the crystallinity of the nanowires were determined by high-resolution transmission electron microscopy. The thermoelectric properties (Seebeck coefficient and electrical conductivity) of single p- and n-type nanowires, with diameter 80 nm and 200 nm, respectively, were determined as a function of temperature before and during heating in a helium atmosphere up to 300 K along the growth direction of the nanowires. After additional annealing in a tellurium atmosphere at 525 K, significantly enhanced transport properties are observed. Bulk-like power factors are achieved. In Bi38Te55Se7 nanowires, the Seebeck coefficients increase to -115 μV K(-1) and the thermoelectric power factors increase to 2820 μW K(-2) m(-1) at room temperature. In Bi15Sb29Te56 nanowires, Seebeck coefficients of up to S = +156 μV K(-1) and power factors of up to 1750 μW K(-2) m(-1) are obtained at room temperature.
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http://dx.doi.org/10.1088/0957-4484/24/49/495402 | DOI Listing |
Environ Sci Technol
January 2025
State Key Laboratory of Marine Resources Utilization in South China Sea, School of Marine Science and Engineering, Hainan University, Haikou 570228, China.
In response to the 2023 "Action Plan for Methane Emission Control" in China, which mandates precise methane (CH) emission accounting, we developed a dynamic model to estimate CH emissions from fossil-fuel and food systems in China for the period 1990-2020. We also analyzed their socioeconomic drivers through the Logarithmic Mean Divisia Index (LMDI) model. Our analysis revealed an accelerated emission increase (850.
View Article and Find Full Text PDFChem Commun (Camb)
January 2025
Fachgebiet Angewandte Nanophysik, Institut für Physik & IMN MacroNano, Technische Universität Ilmenau, Ilmenau 98693, Germany.
Organic materials, with abundant resources, low cost, high flexibility, tunable structures, lightweight nature, and wide operating temperature range, are regarded as promising candidates for sodium-ion batteries (SIBs). Unfortunately, their poor electronic and ionic conductivity remain significant challenges, hindering the achievement of high power density for sodium storage. Power density, a critical factor in battery performance evaluation, is essential for assessing fast charging capabilities.
View Article and Find Full Text PDFSmall
January 2025
Center of Quantum Materials and Devices, College of Physics, Chongqing University, Chongqing, 401331, China.
Spin-orbit coupling (SOC) induced nontrivial bandgap and complex Fermi surface has been considered to be profitable for thermoelectrics, which, however, is generally appreciable only in heavy elements, thereby detrimental to practical application. In this study, the SOC-driven extraordinary thermoelectric performance in a light 2D material Fe₂S₂ is demonstrated via first-principles calculations. The abnormally strong SOC, induced by electron correlation through 3d orbitals polarization, significantly renormalizes the band structures, which opens the bandgap via Fe 3d orbitals inversion, exposes the second conduction valley with weak electron-phonon coupling, and aligns the energy of Fe 3d and S 3p orbitals with divergent momentum in valence band.
View Article and Find Full Text PDFBr J Psychiatry
January 2025
Center for Neurobehavioral Genetics, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California Los Angeles, USA; Department of Human Genetics, University of California Los Angeles, USA; and Department of Computational Medicine, University of California Los Angeles, USA.
Background: Accurate diagnosis of bipolar disorder (BPD) is difficult in clinical practice, with an average delay between symptom onset and diagnosis of about 7 years. A depressive episode often precedes the first manic episode, making it difficult to distinguish BPD from unipolar major depressive disorder (MDD).
Aims: We use genome-wide association analyses (GWAS) to identify differential genetic factors and to develop predictors based on polygenic risk scores (PRS) that may aid early differential diagnosis.
BMJ Open
December 2024
Department of Pharmacy, Fujian Maternity and Child Health Hospital College of Clinical Medicine for Obstetric & Gynecology and Pediatrics, Fujian Medical University, Fuzhou, China
Introduction: Compared with the guideline-recommended use of low-molecular weight heparin (LMWH) for 28 days to prevent venous thromboembolism (VTE) after cytoreductive surgery, oral rivaroxaban avoids the pain and inconvenience of daily injections and reduces medical expenses. The proposed randomised controlled trial (RCT) aims to compare the efficacy and safety of rivaroxaban and enoxaparin in preventing VTE in patients after surgery for gynaecological malignancies and to provide a reference for clinical medication prevention.
Methods And Analysis: This is a single-centre, randomised, controlled, open-label and assessor-blind clinical trial.
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