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The Arrhenius plot (logarithmic plot vs. inverse temperature) is represented by a straight line if the Arrhenius equation holds. A curved Arrhenius plot (mostly concave) is usually described phenomenologically, often using polynomials of T or 1/T. Many modifications of the Arrhenius equation based on different models have also been published, which fit the experimental data better or worse. This paper proposes two solutions for the concave-curved Arrhenius plot. The first is based on consecutive A→B→C reaction with rate constants k1 ≪ k2 at higher temperatures and k1 ≫ k2 (or at least k1 > k2) at lower temperatures. The second is based on the substitution of the temperature T the by temperature difference T − T0 in the Arrhenius equation, where T0 is the maximum temperature at which the Arrheniusprocess under study does not yet occur.

Data‐driven approaches in materials science demand the collection of large amounts of data on the target materials at synchrotron beamlines. To accurately gather suitable experimental data, it is essential to establish fully automated measurement systems to reduce the workload of the beamline staff. Moreover, the recent COVID‐19 pandemic has further emphasized the necessity of automated and/or remote measurements at synchrotron beamlines. Here, the installation of a new sample changer combined with a high‐temperature furnace and a fully automated alignment system on beamline BL04B2 at SPring‐8 is reported. The system allows X‐ray total scattering measurements of up to 21 samples at different temperatures (from room temperature to 1200°C) to be conducted without any human assistance. The implementation of a new, fully automated X‐ray total scattering system on beamline BL04B2 at SPring‐8 is described.

Context To determine the miscibility of liquids at high temperatures using the concept of Hildebrand solubility parameter δ , the current practice is to examine the difference in δ between two liquids at room temperature, assuming that δ is not sensitive to temperature . However, such an assumption may not be valid for certain polymer blends and solutions. Therefore, a knowledge of the δ values of the liquids of interest at high temperatures is desirable. The determination of δ at high temperatures, especially for high-molecular-weight polymers, is impossible, as polymers have vapor pressures of zero. To this end, molecular dynamics (MD) simulations provide a practical means for determining δ over a wide range of temperatures. In this work, we study the temperature dependence of δ of five hydrocarbon polymers: polyethylene (PE), isotactic and atactic polypropylene ( i -PP and a -PP), polyisobutylene (PIB), and polyisoprene (PI) in five hydrocarbon solvents: n -pentane, n -hexane, n -dodecane, isobutene, and cyclohexane. The polymers are modeled as monodisperse chains with 100 repeat units. The average δ values of PE, i -PP, a -PP, PIB, and PI at 300 K are determined as 18.6, 14.9, 14.6, 14.3, and 16.4 MPa 1/2 , respectively, in a good agreement with experimental data. The δ values of these polymers at various temperatures are also determined. The temperature dependence of δ is fitted to two linear equations, one above and the other below the polymer’s glass transition temperature T g . The δ values are more sensitive to temperature at T  ≥  T g . The T g values of the polymers, determined based upon their specific volumes and δ values agree with the experiment qualitatively. The determination of the temperature dependence of δ has a great potential for industrial applications, such as determining miscibility, developing polymeric organogelators as flocculants and oil spill treating agents, and identifying potential solvents and ideal processing temperatures. Methods The MD simulations are performed using the GROMACS 2022.3 package with optimized potential for liquid simulations-all atom (OPLS-AA) force field parameters. All polymers are built as extended chains using CHARMM-GUI Polymer Builder. Graphical Abstract

Climate model simulations provide useful information to assess changes in climate extremes (e.g. droughts and hot extremes) under global warming for climate policies and mitigation measures. Due to systematic biases in climate model simulations, bias correction (BC) methods have been employed to improve simulations of climate variables such as precipitation and temperature. Previous studies mostly focus on individual variables while the correction of precipitation-temperature (P-T) dependence, which is closely related to compound dry and hot events (CDHEs) that may lead to amplified impacts, is still limited. In this study, we evaluated the performance of the multivariate BC (MBC) approach (i.e. MBCn and MBCr) for adjusting P-T dependence and associated likelihoods of CDHEs in China based on 20 Coupled Model Intercomparison Project Phase 6 (CMIP6) models with observations from CN05.1. Data for the period 1961–1987 were used for model calibrations and those for 1988–2014 were used for model validations. Overall, the MBC can improve the simulation of P-T dependence and associated CDHEs with large regional variations. For P-T dependence, the median values of root mean squared error (RMSE) for corrected simulations show a decreased bias of 5.0% and 4.3% for MBCn and MBCr, respectively, compared with those of raw CMIP6 models. For the likelihood of CDHEs, a decrease of 1.0% and 7.2% in RMSE is shown based on the MBCn and MBCr, respectively. At the regional scale, the performance of the MBC varies substantially, with the reduced RMSE up to 34.8% and 18.7% for P-T dependence and likelihood of CDHEs, respectively, depending on regions and MBC methods. This study can provide useful insights for improving model simulations of compound weather and climate extremes for impact studies and mitigation measures.

The temperature-dependent changes in the capacitance–voltage (C–V) and conductivity–voltage (G/w–V) curves of the Au/C20H12/n-Si structure were investigated in the high-temperature range of 280–400 K. C and G values were strongly dependent on both temperature and bias voltage, especially in the depletion and accumulation regions in the experimental results. Basic electrical parameters including dopant donor atoms (ND), depletion layer thickness (Wd), barrier height (ФB), series resistance (Rs), and Fermi energy level (EF) were calculated from the reverse bias (1/C2–V) characteristic for each temperature. Among the parameters that have a significant effect on the performance of these devices, the voltage-dependent resistance profile (Ri) was obtained using the Nicollian-Brews technique, and the surface states (Nss) were obtained using the Hill-Coleman technique. While ND increases with increasing temperature, Rs, Nss, and ФB decrease. The observed abnormal/anomalous peak in both the C–V and Rs–V plots and shifting of its positions and magnitude were attributed to a special distribution of Nss in the semiconductor bandgap and their reordering/restriction under temperature and electric field effects. Both the C–V and G/w–V curves of the structure at room temperature were corrected considering the Rs effect to obtain the real C and G/w values.

Nanoscale air channel transistors (NACTs) have received significant attention due to their remarkable high‐frequency performance and high switching speed, which is enabled by the ballistic transport of electrons in sub‐100 nm air channels. Despite these advantages, NACTs are still limited by low currents and instability compared to solid‐state devices. GaN, with its low electron affinity, strong thermal and chemical stability, and high breakdown electric field, presents an appealing candidate as a field emission material. Here, a vertical GaN nanoscale air channel diode (NACD) with a 50 nm air channel is reported, fabricated by low‐cost IC‐compatible manufacturing technologies on a 2‐inch sapphire wafer. The device boasts a record field emission current of 11 mA at 10 V in the air and exhibits outstanding stability during cyclic, long‐term, and pulsed voltage testing. Additionally, it displays fast switching characteristics and good repeatability with a response time of fewer than 10 ns. Moreover, the temperature‐dependent performance of the device can guide the design of GaN NACTs for applications in extreme conditions. The research holds great promise for large current NACTs and will speed up their practical implementation. A vertical GaN nanodiode with a 50 nm air channel is reported, fabricated using IC‐compatible technologies, with a record field emission current of 11 mA@10 V. Notably, the device displays outstanding stability and fast switching characteristics with a sub‐10 ns response time. Additionally, the temperature‐dependent performance can guide the design of GaN NACTs for applications in extreme conditions.

Rate-limiting steps in the dark-to-light transition of Photosystem II (PSII) were discovered by measuring the variable chlorophyll-a fluorescence transients elicited by single-turnover saturating flashes (STSFs). It was shown that in diuron-treated samples: (i) the first STSF, despite fully reducing the QA quinone acceptor molecule, generated only an F1(

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