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• In-situ performance of a thermoelectric generator in the core of a nuclear reactor. • Thermoelectric performance degrades under irradiation at low temperatures. • Significant recovery in performance under irradiation at high temperatures. • Operation at high temperature prevents unfavorable phase change. • Nanostructured thermoelectrics can provide stable power in the nuclear reactor core. Thermoelectric energy converters offer a promising solution to generate electrical power using heat in the nuclear reactor core. Despite significant improvements in thermoelectric efficiency of nanostructured materials, the performance of these advanced materials has yet to be demonstrated in the harsh radiation environment of a reactor core. Herein, we demonstrate a thermoelectric generator (TEG) made from nanostructured bulk half-Heusler (HH) materials generating stable electrical power density > 1140 W/m2 after 30 days in the MIT Nuclear Research Reactor under an unprecedented fast-neutron (>1 MeV) fluence of 1.5 × 1020 n/cm2. Despite an initial degradation due to irradiation damage when operating under relatively low temperatures, our TEG showed a 20-fold increase in power output when operating under high temperature due to in-situ annealing and resulting thermoelectric property recovery. First-principles modeling indicates that a chemically disordered metallic phase was formed under irradiation at lower temperatures, resulting in a drastic degradation in thermoelectric properties, while at sufficiently high temperatures the system returned to the initial chemically ordered HH phase and the thermoelectric properties recovered. Transmission electron microscopy and electron diffraction demonstrated that the chemically disordered phase was formed upon ion irradiation, confirming the prediction from first-principles simulations. The results suggest that with proper control over the TEG operating temperatures, the nanostructured bulk TEGs could produce stable electrical power and operate indefinitely in the core of a nuclear reactor. [ABSTRACT FROM AUTHOR]

Fusion power holds promise as an ultimate energy source. However, achieving true sustainability in fusion energy requires addressing the embrittlement of polycrystalline materials in fusion reactors caused by helium, which leads to premature failure, often within a year. Here we experimentally demonstrate that nanodispersoids with constitutional vacancy-like atomic-scale free volume can securely store helium, not only at the matrix-dispersoid interface but also within their bulk lattices, which suggests their effectiveness in delaying critical helium damage of the polycrystalline matrix. The selected model nano-heterophase, fayalite Fe 2 SiO 4 , possesses moderately strong lattice sinks for helium while undergoing lattice distortions upon helium absorption. These distortions cause observable changes in peak intensities of X-ray diffraction (XRD) patterns, distinct from changes resulting from other factors like radiation damage. By comparing grazing incidence XRD patterns with ab initio computed patterns, we show that such nano-heterophases can store up to ∼10 at% helium within their bulk lattice, forming a "helide compound." Incorporating just 1 vol% of Fe 2 SiO 4 reduces helium bubble size and number density by >20 % and >50 %, respectively. These findings suggest that 1–2 vol% of appropriate nano-heterophases can accommodate a few thousand appm of bulk helium, expected to be generated over a 10-year operational period. Nano-heterophases with constitutional vacancy-like atomic-scale free volume can divert and securely store helium within their "bulk lattices" over 10 at%, thereby significantly delaying the occurrence of critical helium damage in polycrystalline fusion structural materials. Incorporating 1–2 vol% of such nano-heterophases can effectively accommodate a few thousand appm of bulk helium, expected to be generated over a 10-year lifespan of civilian-fusion operation. [Display omitted] [ABSTRACT FROM AUTHOR]

Coronary artery disease has one of the highest mortality rates in the country, and methods such as thrombolysis and percutaneous coronary intervention (PCI) can effectively improve symptoms and reduce mortality, but most patients still experience symptoms such as chest pain after PCI, which seriously affects their quality of life and increases the incidence of adverse cardiovascular events (myocardial ischaemia reperfusion injury, MIRI). MIRI has been shown to be closely associated with circadian rhythm disorders and mitochondrial dysfunction. Mitochondria are a key component in the maintenance of normal cardiac function, and new research shows that mitochondria have circadian properties. Traditional Chinese medicine (TCM), as a traditional therapeutic approach characterised by a holistic concept and evidence-based treatment, has significant advantages in the treatment of MIRI, and there is an interaction between the yin-yang theory of TCM and the circadian rhythm of Western medicine at various levels. This paper reviews the clinical evidence for the treatment of MIRI in TCM, basic experimental studies on the alleviation of MIRI by TCM through the regulation of mitochondria, the important role of circadian rhythms in the pathophysiology of MIRI, and the potential mechanisms by which TCM regulates mitochondrial circadian rhythms to alleviate MIRI through the regulation of the biological clock transcription factor. It is hoped that this review will provide new insights into the clinical management, basic research and development of drugs to treat MIRI. [Display omitted] • Traditional Chinese medicine(TCM) as a superior therapy for improving MIRI. • TCM ameliorates MIRI by protecting mitochondria. • Circadian rhythm disruption and mitochondrial damage as important pathogenic mechanisms in MIRI. • TCM is a potential therapeutic strategy to improve MIRI by regulating mitochondrial circadian rhythms. [ABSTRACT FROM AUTHOR]

[Display omitted] Nickel-titanium (NiTi) shape memory alloys (SMA) are widely used, however simulating the martensitic transformation of NiTi from first principles remains challenging. In this work, we developed a neural network interatomic potential (NNIP) for near-equiatomic Ni-Ti system through active-learning based acquisitions of density functional theory (DFT) training data, which achieves state-of-the-art accuracy. Phonon dispersion and potential-of-mean-force calculations of the temperature-dependent free energy have been carried out. This NNIP predicts temperature-induced, stress-induced, and defect-induced martensitic transformations from atomic simulations, in significant agreement with experiments. The NNIP can directly simulate the superelasticity of NiTi nanowires, providing a tool to guide their design. [ABSTRACT FROM AUTHOR]

The extraction of Pd2+ with N,N -dialkyl-2-(3-(pyridine-2-yl)-1 H -pyrazole-1-yl) acetamide (A-C-PzPy) and N,N -dialkyl-3-(pyridine-2-yl)-1 H -pyrazole-1-carboxamide (A-PzPy) from HNO 3 medium, as well as the complexation of Pd2+ with A-C-PzPy were investigated. The use of tert-butyl benzene (TBB) as a diluent for A-C-PzPy offered significantly better extractability toward Pd2+, compared to that of A-PzPy. This study demonstrated strong extractability, high selectivity, high loading capacity, and fast extraction kinetics for DOct-C-PzPy toward Pd2+ from highly acidic HNO 3 solution (up to 5.0 mol/L). Slope analysis showed the formation of 1:1 type of extracted species of Pd2+ with DOct-C-PzPy ligand. The extraction was a spontaneous and endothermic process with increased entropy. The analyses of electrospray ionization mass spectrometry (ESI-MS), Fourier transform infrared (FT-IR) and UV–vis spectrophotometric titration revealed that the composition of the extracted neutral complex species was Pd(NO 3) 2 (DOct-C-PzPy). Combining the results of solvent extraction and complexation study, a neutral complexation extraction model is proposed. Furthermore, the stability constants (log β) for the complexation of Pd2+ with A-C-PzPy are also presented. [Display omitted] • DOct-C-PzPy exhibited high extractability and selectivity for Pd2+ in HNO 3 solution. • The composition of extraction complex was determined by MS, IR and UV–vis analyses. • The stability constants of Pd2+ complexes were obtained by UV–vis spectral titration. • A neutral extraction model of Pd2+ in HNO 3 solution by DOct-C-PzPy was proposed. [ABSTRACT FROM AUTHOR]

• The extraction of DGAs towards La3+, Pr3+, Nd3+, Eu3+, Gd3+, Y3+, Er3+ and Yb3+ was systematically investigated. • The extraction thermodynamic parameters (Δ H , Δ S and Δ G) were obtained. • The complexation of DGAs with Eu3+ was explored by means of FT-IR, 1H NMR, Luminescence spectroscopic titration and microcalorimetric titration. • The complexation stability constants and thermodynamic parameters of Eu3+ with DGAs were given. The extraction and complexation behaviors of four tetraalkyl diglycolamide (TRDGA, where R represents n -butyl, n -hexyl, n -octyl and 2-ethylhexyl) ligands with linear chain or branched chain structure were described with respect to La3+, Pr3+, Nd3+; Eu3+, Gd3+; Y3+, Er3+ and Yb3+ as the representatives of light, middle and heavy rare-earth group ions in HNO 3 solution. Effects of acidity, ligand concentration and temperature on the distribution ratio of these ions were examined. High acidity was good for the extraction. For same metal ion, the extractability of DGA ligands followed the order of T2EHDGA < THDGA < TODGA < TBDGA at the same acidity, which was also supported by nuclear magnetic resonance (NMR) analyses. Meanwhile, for different metal ions, their extracted efficiencies by the same DGA ligand increased in the sequence of lanthanide contraction. The average separation factors of adjacent lanthanides within light, middle and heavy rare-earth groups could attain about 2.4, 1.7 and 2.1, respectively. Slope analysis indicated that the formation of predominant 1:3 and 1:2 metal/ligand extracted species for linear chain and branched DGA, respectively. In methanol solution, 1:1, 1:2 and 1:3 Eu3+/DGA species were also observed using fluorescence spectroscopy titration. Fourier transform infrared spectroscopy (FT-IR) analyses suggested that the carbonyl oxygens compared with ether oxygen play a dominant role in coordination. Moreover, the stability constants (log β) and the thermodynamic parameters (Δ H , Δ S and Δ G) for the complexation of Eu3+ with DGAs were also presented. [ABSTRACT FROM AUTHOR]