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We propose an efficient algorithm for a minimum free energy path calculation based on the path integral hybrid Monte Carlo (PIHMC) method by combining the climbing image-nudged elastic band (CI-NEB) and the thermodynamic integration (TI) methods. Here, the CI-NEB and the TI methods are used to find a transition state along the reaction path and evaluate the free energy path, respectively. Our algorithm is applied to the Walden inversion reaction of the hydronium ions (H3O+). The numerical results show that the computational effort by our algorithm is significantly reduced compared to that of the previously proposed algorithm combining PIHMC without losing accuracy. We also demonstrate the importance of temperature and isotope effects on the addition reaction of hydrogen isocyanide to formaldehyde. In this reaction, the nuclear quantum effect causes the structural change at the TS and decreases the energy barrier. [ABSTRACT FROM AUTHOR]

We present a detailed spectroscopic analysis of the first absorption band of the six possible conformers of 1,6-diphenyl-1,3,5-hexatriene, obtained by changing the configuration of trans double bonds to cis. To this end, we computed the absorption spectra using FCclasses 3.0 code. First, we assessed the performance of PBE0 and CAM-B3LYP density functional theory functionals with different basis sets to reproduce the experimental spectra. Additionally, we considered different models to compute the spectra. PBE0/def2tZVP with an adiabatic hessian model with internal coordinates yields results in very good agreement with experimental data. Subsequently, we analyzed the different contributions of vibronic transition to the spectral structure, correlating ground state conformation with spectral shape, and studied the effect of temperature on the absorption first band. [ABSTRACT FROM AUTHOR]

X-ray self-heating is a common by-product of X-ray Free Electron Laser (XFEL) techniques that can affect targets, optics, and other irradiated materials. Diagnosis of heating and induced changes in samples may be performed using the x-ray beam itself as a probe. However, the relationship between conditions created by and inferred from x-ray irradiation is unclear and may be highly dependent on the material system under consideration. Here, we report on a simple case study of a titanium foil irradiated, heated, and probed by a MHz XFEL pulse train at 18.1 keV delivered by the European XFEL using measured x-ray diffraction to determine temperature and finite element analysis to interpret the experimental data. We find a complex relationship between apparent temperatures and sample temperature distributions that must be accounted for to adequately interpret the data, including beam averaging effects, multivalued temperatures due to sample phase transitions, and jumps and gaps in the observable temperature near phase transformations. The results have implications for studies employing x-ray probing of systems with large temperature gradients, particularly where these gradients are produced by the beam itself. Finally, this study shows the potential complexity of studying nonlinear sample behavior, such as phase transformations, where biasing effects of temperature gradients can become paramount, precluding clear observation of true transformation conditions. [ABSTRACT FROM AUTHOR]

We have done comprehensive first-principles calculations of He-vacancy-interstitial clusters in FCC nickel. The calculated total binding energy of V n (Ni vacancy cluster), I n (Ni interstitial cluster), He n (helium interstitial cluster), He n V (helium interstitials in one vacancy), and He n V 2 (helium interstitials in one divacancy) cluster is reported. The total binding energy of a two Ni interstitial cluster is relatively large (1.07 eV), and the binding energy between a monovacancy and a vacancy cluster containing < 20 vacancies is relatively small (< 0.8 eV). The dissociation/emission energy barrier of a Ni interstitial from a He 3 interstitial cluster (three helium interstitial clusters) and a He 8 V cluster (eight helium interstitials in one vacancy) is ≤ 1.06 and ≤ 1.32 eV, respectively. The diffusion activation energy of helium is 1.36 eV via a dissociative mechanism. Comparisons with reported experimental results of helium diffusion and helium desorption have been done to verify the calculation results. The relative stability of stacking fault tetrahedron and void has been investigated further based on quasi-harmonic phonon calculations directly to consider the temperature effects. The reported binding energy results can be used to build molecular simulation potentials or provide input parameters for the cluster dynamics or lattice Monte Carlo simulations of helium-defect cluster evolution. [ABSTRACT FROM AUTHOR]

Carbonyl groups (C=O) play crucial roles in the photophysics and photochemistry of biological systems. O1s x-ray photoelectron spectroscopy allows for targeted investigation of the C=O group, and the coupling between C=O vibration and O1s ionization is reflected in the fine structures. To elucidate its characteristic vibronic features, systematic Franck–Condon simulations were conducted for six common biomolecules, including three purines (xanthine, caffeine, and hypoxanthine) and three pyrimidines (thymine, 5F-uracil, and uracil). The complexity of simulation for these biomolecules lies in accounting for temperature effects and potential tautomeric variations. We combined the time-dependent and time-independent methods to efficiently account for the temperature effects and to provide explicit assignments, respectively. For hypoxanthine, the tautomeric effect was considered by incorporating the Boltzmann population ratios of two tautomers. The simulations demonstrated good agreement with experimental spectra, enabling differentiation of two types of carbonyl oxygens with subtle local structural differences, positioned between two nitrogens (O1) or between one carbon and one nitrogen (O2). The analysis provided insights into the coupling between C=O vibration and O1s ionization, consistently showing an elongation of the C=O bond length (by 0.08–0.09 Å) upon O1s ionization. [ABSTRACT FROM AUTHOR]

Recently, high entropy alloy (HEA) has become a research hotspot as a new candidate structural material in nuclear reactors due to its good irradiation resistance in swelling and hardening. Focusing on the temperature effect of irradiation damage, this work investigated the influence of irradiation temperature on dislocation evolution and irradiation hardening of HEAs. CoCrFeMnNi HEA was irradiated by high-energy Fe ions at room temperature and 500 °C. It was found that dense small dislocations were produced in the damage attenuation region (i.e., the tail of the ion range) of HEAs after irradiation at room temperature, whereas the irradiation-induced dislocations could not be observed in the damage attenuation region when the irradiation temperature was increased to 500 °C. For the small-sized dislocations, dissociation may occur more easily than long-range migration in HEAs (such as CoCrFeNi systems) due to the inhibition of defect migration and the decrease in defect binding energy, and this order is reversed in pure metals (such as Ni, W). Therefore, at 500 °C irradiation, small dislocations in the damage attenuation region of CoCrFeMnNi HEAs were dissociated before migrating to deeper regions, thereby resulting in the depth of dislocation distribution smaller than the stopping and range of ions in matter-calculated damage stopping depth, unlike the phenomenon in pure metals where dislocations migrated to regions exceeding the calculated depth. In addition, the dislocation density of CoCrFeMnNi HEAs decreased significantly due to the promotion of dissociation and merging of dislocations by elevated temperatures, and the hardening after 500 °C irradiation was less than that after room temperature irradiation. [ABSTRACT FROM AUTHOR]

Tree tensor network states (TTNS) decompose the system wavefunction to the product of low-rank tensors based on the tree topology, serving as the foundation of the multi-layer multi-configuration time-dependent Hartree method. In this work, we present an algorithm that automatically constructs the optimal and exact tree tensor network operators (TTNO) for any sum-of-product symbolic quantum operator. The construction is based on the minimum vertex cover of a bipartite graph. With the optimal TTNO, we simulate open quantum systems, such as spin relaxation dynamics in the spin-boson model and charge transport in molecular junctions. In these simulations, the environment is treated as discrete modes and its wavefunction is evolved on equal footing with the system. We employ the Cole–Davidson spectral density to model the glassy phonon environment and incorporate temperature effects via thermo-field dynamics. Our results show that the computational cost scales linearly with the number of discretized modes, demonstrating the efficiency of our approach. [ABSTRACT FROM AUTHOR]

Dissipative particle dynamics (DPD) is a widespread computational tool to simulate the behavior of soft matter and liquids in and out of equilibrium. Although there are many applications in which the effect of temperature is relevant, most of the DPD studies have been carried out at a fixed system temperature. Therefore, this work investigates how to incorporate the effect of system temperature variation within the DPD model to capture realistic temperature-dependent system properties. In particular, this work focuses on the relationship between temperature and transport properties, and therefore, an extended DPD model for transport properties prediction is employed. Transport properties, unlike the equilibrium properties, are often overlooked despite their significant influence on the flow dynamics of non-isothermal mesoscopic systems. Moreover, before simulating the response of the system induced by a temperature change, it is important to first estimate transport properties at a certain temperature. Thus here, the same fluid is simulated across different temperature conditions using isothermal DPD with the aim to identify a temperature-dependent parametrization methodology, capable of ensuring the correctness of both equilibrium and dynamical properties. Liquid water is used as a model system for these analyses. This work proposes a temperature-dependent form of the extended DPD model where both conservative and non-conservative interaction parameters incorporate the variation of the temperature. The predictions provided by our simulations are in excellent agreement with experimental data. [ABSTRACT FROM AUTHOR]

The primary objective of the present investigation is to elucidate the operative micromechanisms influencing the strain rate sensitivity and activation volume in (FeCrNi)99Si1 and FeMnNi medium-entropy alloys. Room-temperature nanoindentation experiments at different loading rates were performed to study the evolution of the strain rate sensitivity and activation volume in (FeCrNi)99Si1 and FeMnNi medium-entropy alloys. The (FeCrNi)99Si1 samples were subjected to plane strain deformation by rolling at 77 and 300 K to study the effect of temperature on the strain rate sensitivity, while the FeMnNi and (FeCrNi)99Si1 samples were subjected to simple shear deformation by high-pressure torsion at 300 K to examine the effect of strains. Contrary to the well-documented trend observed in fcc metals and alloys, where the strain rate sensitivity typically increases with decreasing grain size, the present study reveals a distinct behavior for the current alloys. Similarly, these alloys are characterized by extremely low activation volumes of a few tens of b3 compared to 100–1000 b3 for conventional fcc metals and alloys in the microcrystalline grain size regime. Unlike conventional fcc metals and alloys, there is an insignificant change in the activation volume of the current high-/medium-entropy alloy (H/MEA) with decreasing grain size from the microcrystalline to nanocrystalline regime. The unique evolution of strain rate sensitivity and activation volume in H/MEAs is explained in terms of the evolution of distinct dislocation structures as well as synergistic operation of additional mechanisms such as twinning, phase transformation from fcc to hcp phases, cluster strengthening, and short-range ordering due to the aperiodic energy landscape existing in MEAs. [ABSTRACT FROM AUTHOR]

It is significant to investigate the calcium carbonate (CaCO3) precipitation mechanism during the carbon capture process; nevertheless, CaCO3 precipitation is not clearly understood yet. Understanding the carbonation mechanism at the atomic level can contribute to the mineralization capture and utilization of carbon dioxide, as well as the development of new cementitious materials with high-performance. There are many factors, such as temperature and CO2 concentration, that can influence the carbonation reaction. In order to achieve better carbonation efficiency, the reaction conditions of carbonation should be fully verified. Therefore, based on molecular dynamics simulations, this paper investigates the atomic-scale mechanism of carbonation. We investigate the effect of carbonation factors, including temperature and concentration, on the kinetics of carbonation (polymerization rate and activation energy), the early nucleation of calcium carbonate, etc. Then, we analyze the local stresses of atoms to reveal the driving force of early stage carbonate nucleation and the reasons for the evolution of polymerization rate and activation energy. Results show that the higher the calcium concentration or temperature, the higher the polymerization rate of calcium carbonate. In addition, the activation energies of the carbonation reaction increase with the decrease in calcium concentrations. [ABSTRACT FROM AUTHOR]

The outstanding catalytic property of cerium oxide (CeO2) strongly depends on the polaron formation due to the oxygen vacancy ( V ̈ O ) defect and Ce4+ to Ce3+ transformation. Temperature plays an important role in the case of polaron generation in CeO2 and highly influences its electrical transport properties. Therefore, a much needed attention is required for detailed understanding of the effect of temperature on polaron formation and oxygen vacancy migration to get an idea about the improvement in the redox property of ceria. In this work, we have probed the generation of polarons in CeO2 thin-film deposited on a silicon (Si) substrate using the resonance photoemission spectroscopy (RPES) study. The RPES data show an increase in polaron density at the substrate–film interface of the thermally annealed film, indicating the formation of an interfacial Ce2O3 layer, which is, indeed, a phase change from the cubic to hexagonal structure. This leads to a modified electronic band structure, which has an impact on the capacitance–voltage (C–V) characteristics. This result nicely correlates the microscopic property of polarons and the macroscopic transport property of ceria. [ABSTRACT FROM AUTHOR]

We report a theoretical investigation of temperature, size, and composition effects on the structural, energetic, and electronic properties of the (La4O6)n, (La2Ce2O7)n, and (Ce4O8)n nanoclusters (NCs) for n = 10, 18. Furthermore, we investigated the single O vacancy formation energy as a function of the geometric location within the NC. Our calculations are based on the combination of force-field molecular dynamics (MD) simulations and density functional theory calculations. We identified a phase transition from disordered to ordered structures for all NCs via MD simulations and structural analysis, e.g., radius changes, radial distribution function, common neighbor analysis, etc. The transition is sharp for La36Ce36O126, La20Ce20O70, and Ce72O144 due to the crystalline domains in the core and less abrupt for Ce40O80, La40O60, and La72O108. As expected, radius changes are abrupt at the transition temperature, as are morphological differences between NCs located below and above the transition temperature. We found a strong dependence on the O vacancy formation energy (Evac) and its location within the NCs. For example, for La40O60, Evac decreases almost linearly as the distance from the geometric center increases; however, the same trend was not observed for Ce40O80, while there are large deviations from the linear trend for La20Ce20O70. Evac has smaller values for Ce40O80 and higher values for La40O60, that is, almost three times, while Evac has intermediate values for mixed oxides, as expected from weighted averages. Therefore, the mixture of one formula unit of La2O3 with two formula units of CeO2 has the effect of increasing the stability of CeO2 (binding energy), which increases the magnitude of the formation energy of the O vacancy. [ABSTRACT FROM AUTHOR]

In this work, the univariant two-phase coexistence line of the tetrahydrofuran (THF) hydrate is determined from 100 to 1000 bar by molecular dynamics simulations. This study is carried out by putting in contact a THF hydrate phase with a stoichiometric aqueous solution phase. Following the direct coexistence technique, the pressure is fixed, and the coexistence line is determined by analyzing if the hydrate phase grows or melts at different values of temperature. Water is described using the well-known TIP4P/Ice model. We have used two different models of THF based on the transferable parameters for phase equilibria-united atom approach (TraPPE-UA), the original (flexible) TraPPe-UA model and a rigid and planar version of it. Overall, at high pressures, small differences are observed in the results obtained by both models. However, large differences are observed in the computational efforts required by the simulations performed using both models, being the rigid and planar version much faster than the original one. The effect of the unlike dispersive interactions between the water and THF molecules is also analyzed at 250 bar using the rigid and planar THF model. In particular, we modify the Berthelot combining rule via a parameter ξO-THF that controls the unlike water–THF dispersive interactions. We analyze the effect on the dissociation temperature of the hydrate when ξO-THF is modified from 1.0 (original Berthelot combining rule) to 1.4 (modified Berthelot combining rule). We use the optimized value ξO-THF = 1.4 and the rigid THF model in a transferable way to predict the dissociation temperatures at other pressures. We find excellent agreement between computer simulation predictions and experimental data taken from the literature. [ABSTRACT FROM AUTHOR]

We present a detailed computational study on the temperature effect of the dynamics and the interfacial width of unentangled cis-1,4 polybutadiene linear chains confined between strongly attractive alumina layers via long, several μs, atomistic molecular dynamics simulations for a wide range of temperatures (143–473 K). We examine the spatial gradient of the translational segmental dynamics and of an effective local glass temperature ( T g L ). The latter is found to be much higher than the bulk Tg for the adsorbed layer. It gradually reduces to the bulk Tg at about 2 nm away from the substrate. For distant regions (more than ≈ 1.2 n m), a bulk-like behavior is observed; relaxation times follow a typical Vogel–Fulcher–Tammann dependence for temperatures higher than Tg and an Arrhenius dependence for temperatures below the bulk Tg. On the contrary, the polymer chains at the vicinity of the substrate follow piecewise Arrhenius processes. For temperatures below about the adsorbed layer's T g L , the translational dynamics follows a bulk-like (same activation energy) Arrhenius process. At higher temperatures, there is a low activation energy Arrhenius process, caused by high interfacial friction forces. Finally, we compute the interfacial width, based on both structural and dynamical definitions, as a function of temperature. The absolute value of the interfacial width depends on the actual definition, but, regardless, the qualitative behavior is consistent. The interfacial width peaks around the bulk Tg and contracts for lower and higher temperatures. At bulk Tg, the estimated length of the interfacial width, computed via the various definitions, ranges between 1.0 and 2.7 nm. [ABSTRACT FROM AUTHOR]

In this work, a calibration of ruby, samarium-doped strontium tetraborate (Sm2+: SrB4O7), and samarium-doped yttrium aluminum garnet (Sm3+: YAG) using Raman and fluorescence spectra was conducted within the temperature range of 296–850 K and pressure range of 0–55 GPa. The obtained calibration can be applied independently for high-temperature or high-pressure conditions and described as the unit form of P = (A′/B′) × [(λ/λT)B′ − 1] with A′ = A (296 K) + A1 × (T − 296) + A2 × (T − 296)2, B′ = B(296 K) + B1 × (T – 296), and λT = λT (296 K) + ΔλT, where the specific parameters are provided in the main text. It was observed that for the λ1 line (5D0 → 7F0 transition, about 685.2 nm under ambient conditions, also known as the 0-0 line) of Sm2+: SrB4O7, the neglect of the temperature effect on the pressure coefficient may lead to an underestimation of pressure above 35–40 GPa, with a maximum deviation of approximately 2.5 GPa within the range of 55 GPa and 850 K. For Sm3+: YAG, it may introduce significant errors under the whole high temperature and high pressure range if the effect of temperature is ignored, that is, about 3.9 GPa for Y1 line (4G5/2 → 6H7/2 transition, about 617.8 nm under ambient conditions) and 4.6 GPa for Y2 line (4G5/2 → 6H7/2 transition, about 616.0 nm under ambient conditions) at 850 K. Comparing the three fluorescence pressure sensors, the ruby has the strongest signal intensity and highest temperature sensitivity, and the Sm2+: SrB4O7 and the Sm3+: YAG possess lower temperature sensibility, wider used temperature range, and better spectral quality under high temperature and high pressure (HTHP), especially Sm2+: SrB4O7, which has a sharp high-intensity single peak λ1, perhaps the most promising sensor for high P–T experiments. Therefore, in view of the potential deflections of fluorescence peaks of each pressure sensor under HTHP, we recommend utilizing the HTHP-corrected relationships for pressure calibration. [ABSTRACT FROM AUTHOR]

Transition state calculation is a critical technique to understand and predict versatile dynamical phenomena in solids. However, the transition state results obtained at 0 K are often utilized for the prediction or interpretation of dynamical processes at high temperatures, and the error bars of such an approximation are largely unknown. In this benchmark study, all the major temperature effects, including lattice expansion, lattice vibration, electron excitation, and band-edge shift, are evaluated with first-principles calculations for defect diffusion in solids. With the inclusion of these temperature effects, the notable discrepancies between theoretical predictions at 0 K and the experimental diffusivities at high temperatures are dramatically reduced. In particular, we find that lattice expansion and lattice vibration are the dominant factors lowering the defect formation energies and hopping barriers at high temperatures, but the electron excitation exhibits minor effects. In sharp contrast to typical assumptions, the attempt frequency with lattice expansion and vibration varies significantly with materials: several THz for aluminum bulk but surprisingly over 500 THz for 4H-SiC. For defects in semiconductors, the band-edge shift is also significant at high temperatures and plays a vital role in defect diffusion. We expect that this study would help accurately predict the dynamical processes at high temperatures. [ABSTRACT FROM AUTHOR]

We present a setup for fast, low-bias (≤ 1 mV) DC transport measurements with μs time resolution for high ohmic resistance (≈ 20 k Ω) semiconducting samples. We discuss the circuitry and instrumentation for the measurement approach that can be applied to any kind of semiconductor device or (gated) two-dimensional material and demonstrate the main measurement artifacts in typical measurements by means of circuit simulation. Based on the latter, we present a simple two-step protocol for eliminating the measurement artifacts reliably. We demonstrate the technique by measuring the transitions between quantum Hall plateaus in the HgTe quantum wells and resolve plateaus as short-lived as 100 μs. [ABSTRACT FROM AUTHOR]

As conducting polymers become increasingly important in electronic devices, understanding their charge transport is essential for material and device development. Various semi-empirical approaches have been used to describe temporal charge carrier dynamics in these materials, but there have yet to be any theoretical approaches utilizing ab initio molecular dynamics. In this work, we develop a computational technique based on ab initio Car–Parrinello molecular dynamics to trace charge carrier temporal motion in archetypical conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT). Particularly, we analyze charge dynamics in a single PEDOT chain and in two coupled chains with different degrees of coupling and study the effect of temperature. In our model we first initiate a positively charged polaron (compensated by a negative counterion) at one end of the chain, and subsequently displace the counterion to the other end of the chain and trace polaron dynamics in the system by monitoring bond length alternation in the PEDOT backbone and charge density distribution. We find that at low temperature (T = 1 K) the polaron distortion gradually disappears from its initial location and reappears near the new position of the counterion. At the room temperature (T = 300 K), we find that the distortions induced by polaron, and atomic vibrations are of the same magnitude, which makes tracking the polaron distortion challenging because it is hidden behind the temperature-induced vibrations. The novel approach developed in this work can be used to study polaron mobility along and between the chains, investigate charge transport in highly doped polymers, and explore other flexible polymers, including n-doped ones. [ABSTRACT FROM AUTHOR]

The Soret effect, temperature gradient driven diffusion, in silicate melts has been investigated intensively in the earth sciences from the 1980s. The SiO2 component is generally concentrated in the hotter region of silicate melts under a temperature gradient. Here, we report that at ultra-high temperatures above ∼3000 K, SiO2 becomes concentrated in the colder region of the silicate melts under a temperature gradient. The interior of an aluminosilicate glass [63.3SiO2–16.3Al2O3–20.4CaO (mol. %)] was irradiated with a 250 kHz femtosecond laser pulse for local heating. SiO2 migrated to the colder region during irradiation with an 800 pulse (3.2 ms irradiation). The temperature analysis indicated that migration to the colder region occurred above 3060 K. In the non-equilibrium molecular dynamics (NEMD) simulation, SiO2 migrated to the colder region under a temperature gradient, which had an average temperature of 4000 K; this result supports the experimental result. On the other hand, SiO2 exhibited a tendency to migrate to the hotter region at 2400 K in both the NEMD and experimental study. The molar volume calculated by molecular dynamics simulation without a temperature gradient indicates two bends at 1650 and 3250 K under 500 MPa. Therefore, the discontinuous (first order) transition with coexistence of two phases of different composition could be related to the migration of SiO2 to colder region. However, the detailed mechanism has not been elucidated. [ABSTRACT FROM AUTHOR]

The displacement function was constructed using Carrera unified formulation (CUF) in combination with Taylor polynomials and the improved Fourier series method (IFSM). This study investigated the vibration characteristics of cylindrical beam made of functionally graded materials (FGM) in a thermal environment. The accuracy of the theoretical model was verified by comparing the calculation results with those obtained using the finite element method. Subsequently, the influential factors were investigated. The variations in material properties with temperature and volume rate index were studied. Additionally, the effects of temperature changes and volume rate index on the thermoelastic vibration of the FGM cylindrical beam were examined. The results indicate that in a uniform temperature field, temperature and volume rate index variations result in changes in the material's physical properties. The modal frequency of the FGM cylindrical beam decreases gradually with increasing temperature and volume rate index. [ABSTRACT FROM AUTHOR]

The difficult recycling and degradation in cured epoxy resins can be solved by introducing dynamic covalent bonds. However, the introduction of dynamic bonds degrades the properties of epoxy resins. In this paper, the dual‐cured epoxy resin with high mechanical properties and high healing efficiency were obtained by constructing interpenetrating networks (IPNs). The effect of IPNs on the recyclability of epoxy resins was investigated. The performance is as follows, the flexural and tensile strengths is 89 and 54.2 MPa, respectively, and the breakdown strength is 32.5 kV/mm. In addition, the recyclability and high healing efficiency of the dual‐cured epoxy resin were verified, and the effect of the hot‐pressing temperature and time on the properties of the recycled samples were investigated. Under certain hot‐pressing conditions, the flexural and tensile strengths of the recycled samples were recovered to 95.06% and 85.28%, respectively, and the breakdown strength was recovered to 83.6%. [ABSTRACT FROM AUTHOR]

Weather and climate changes have been found to affect various socioeconomic outcomes, but the mechanisms that underlie these effects are not fully understood. This article examines the effect of temperature on risk-taking behaviour using daily weather and Powerball sales data in the U.S. The results show that a 1 degree Fahrenheit increase in daily maximum temperature, on average, leads to a 0.30% increase in the Powerball sales in the county. We also find that individuals tend to opt for riskier options on higher-temperature days. Alternative explanations for these effects, such as avoidance behaviour and the income effect, are ruled out as possible drivers of these effects. Our article provides new insights into a potential yet undiscovered channel through which temperature, or more broadly, weather and climate changes can influence socioeconomic outcomes. The findings also have important implications for policymakers concerned about weather and climate changes and their effects on human behaviour. [ABSTRACT FROM AUTHOR]

• The settlement response of different models was examined with respect to field data. • The field data showed resistance to compressibility under increasing applied stress. • Waste disposal under freezing temperatures delayed biodegradation-induced settlement. • Improved predictions by making mechanical creep coefficient stress-dependent. • MCC model's yield surface must account for the time-dependent volumetric strain. • Extended MCC model showed unrealistic increase in the pre-consolidation pressure. Evaluating model parameters through laboratory experiments presents challenges due to waste heterogeneity and scale effects. This study investigates the settlement response of selected models using field-scale data collected from the filling and post-closure phases of the Ste. Sophie landfill in Canada. The first model was based on primary and secondary compression ratios, which could capture the overall settlement but ignored the effect of freezing temperatures on biodegradation-induced settlement. The second model was a composite model with a primary compression ratio, and rheological and first-order decay equations. The model failed to accurately simulate mechanical creep and account for the effect of freezing temperatures. A modified version, with mechanical creep expressed as a function of the applied stress, was proposed and showed improved settlement predictions. The third model was a Generalized Kelvin-Voigt (GKV) model with biodegradation-induced strain expressed as a function of waste expended energy. This model could simulate the field settlement by considering resistance to compressibility and effects of freezing temperatures. The final model was based on the Modified Cam-Clay (MCC) model. Several studies in the literature have extended the MCC yield surface by incorporating specific mechanical and biological creep models. In this study, a general procedure was proposed to integrate time-dependent strain into the MCC yield surface, irrespective of the mechanical and biological creep models used. The extended MCC model revealed an unrealistic increase in preconsolidation pressure, resulting in an initial elastoplastic response followed by a pure elastic response. It also provided a poor estimation of the field settlement. [ABSTRACT FROM AUTHOR]

The ice–water phase transition of bulk ice could develop with varying temperatures and external loads, significantly affecting its mechanical properties. The coupling effect of temperature and shear loads on the thermo‐mechanical properties of bulk ice and its phase transition evolution is poorly understood, especially at the nanoscale. In this study, molecular dynamics (MD) simulation method was employed to investigate the thermo‐mechanical behaviours of bulk ice‐Ih system at the microscale under various temperatures (73–270 K) and shear paths, where its phase transition, elastic properties, structure deformation mechanism and structural anisotropy were discussed. The simulation results show that (1) the shear modulus, shear strength and ultimate shear strain of bulk ice‐Ih system could linearly decrease with rising temperature, aligning with previous studies. (2) Two types of failure modes from bulk ice‐Ih system were founded, such as solid–liquid phase co‐existence at 73–225 K and liquid phase at 250–270 K. (3) Ice melting into water was attributed to the fracture of hydrogen bond during shear process. (4) Compared to vertical shearing (XZ (112¯0$11\bar{2}0$) and YZ (011¯0$01\bar{1}0$)) directions, the mechanical response along the horizontal shearing (XY (0001)) direction was most sensitive to temperature effect. [ABSTRACT FROM AUTHOR]

C14H20 (tetradecapentaene) is a simple model system exhibiting post transition‐state behavior, wherein both the (6 + 4) and (4 + 2) cycloaddition products are formed from one ambimocal transition state structure. We studied the bifurcation dynamics starting from the two ambimodal transition state structures, the chair‐form and boat‐form, using the quasi‐classical trajectory, classical molecular dynamics, and ring‐polymer molecular dynamics methods on the parameter‐optimized semiempirical GFN2‐xTB potential energy surface. It was found that the calculated branching fractions differ between the chair‐form and boat‐form due to the different nature in the IRC pathways. We also investigated the effects of temperature on bifurcation dynamics and found that, at higher temperatures, trajectories stay longer in the intermediate region of the potential energy surface. [ABSTRACT FROM AUTHOR]

Highlights In this paper, the mechanical properties of carbon/Kevlar hybrid fiber‐reinforced resin composites at different temperatures were studied. The hybrid composites were prepared by Vacuum Assisted Resin Infusion (VARI). The sandwich structure of reinforcement consists of Kevlar plain weave fiber as a surface layer and carbon fiber plain weave fabric as a core layer, while the matrix consists of a curing agent and epoxy resin. The bending and tensile properties of the composite specimens were tested at different temperatures using the in situ testing method, separately. The fracture morphology was analyzed using scanning electron microscopy (SEM) to understand the damage mechanism of the material properties at the micro‐scales. The results show that the sandwich composite material shows a positive hybrid effect. The carbon fibers increases effectively the strength and rigidity of the sample, while Kevlar fiber improves the toughness and brittle damage mode. The mechanical properties of hybrid composite laminates are strongly dependent on temperature. The tensile and bending properties of carbon/Kevlar hybrid composites decreased when the temperature increased from −30°C to 40°C. The effect of temperature on the bending properties was more pronounced for the carbon/Kevlar hybrid composites. This study consists of damage analysis and variation analysis of the mechanical behavior of carbon/Kevlar composite specimens, which will lay the foundation to provide basic data for the application of carbon/Kevlar hybrid composites. Advantages of carbon/Kevlar hybrid sandwiched structure on tensile and bending properties. Comprehensive mechanical property testing in multiple composite environments. Based on the hybrid effect and temperature effect, the damage mechanism of the sample was analyzed. [ABSTRACT FROM AUTHOR]

Sintering temperature is decisive for optimizing the grain boundary environment to obtain the high performance ZnO based varistor ceramic. In this work, the impacts of sintering temperature on microstructure and electrical properties of ternary Zn-Sr-Co varistor were investigated. It was found that the distribution of Sr, the critical factor to form grain boundary, was heavily sensitive to sintering temperature. The considerable Sr ions precipitated at grain boundaries and formed the clusters of SrZnO 2 while the sintering temperature increases from 1150 °C to 1190 °C. Besides, the precipitation of Sr led to the large segregation of Co at grain boundaries. The enrichment behavior of Sr and Co contributed to the optimization of grain boundaries, resulting in the enhanced barrier height. As a result, the excellent nonlinear current-voltage performances, i.e., the high nonlinear coefficient of 56.47 and the low leakage current density of 0.73 μA/cm2 were obtained in the ternary ZnO-SrCO 3 -Co 2 O 3 varistor sintered at 1190 °C. However, the grain boundary environment would be destroyed by the excessive temperature of 1210 °C, resulting in the degradation of grain boundary barrier and especially a surge in the leakage current I L from 0.73 to 92.19 μA/cm2. In addition, varying sintering temperature has the important effects on impedance and dielectric properties of the ZnO-SrCO 3 -Co 2 O 3 varistors. The findings provide new perspectives for developing the high-performance ternary ZnO-SrCO 3 -Co 2 O 3 varistor ceramics by optimizing the initial grain boundary environment at different sintering temperatures. [ABSTRACT FROM AUTHOR]

The dense h -BN/MgAl 2 O 4 composites without additives were fabricated by hot-pressed sintering. The effect of sintering temperature and MgAl 2 O 4 on the bulk density, mechanical properties and corrosion resistance were systematically investigated. The results showed that the collaboration of sintering temperature and MgAl 2 O 4 dominated the densification behavior due to the enhanced pore filling effects and solid diffusion. The improved densification and induced microstructure development contributed to enhanced mechanical properties. Additionally, the residual MgAl 2 O 4 is more conducive to forming plate-like complex oxide with molten steel after BN oxidation and B 2 O 3 volatilization. Consequently, the plate-like complex oxide can effectively hinder direct contact between molten steel and the composite, which determines the corrosion resistance of the h -BN/MgAl 2 O 4 composite. This study highlights the enormous potential of h -BN/MgAl 2 O 4 composites for future use as side-sealing materials. [ABSTRACT FROM AUTHOR]

Yttrium-containing ceramics exhibit excellent resistance to water-oxygen corrosion, making them an attractive choice as the modified matrix for SiC f /SiC composites. However, the oxidation products of yttrium-containing ceramics are complex and vary widely in performance. In this study, YSOC ceramics, which are composed of yttrium silicate, SiO 2 , and SiC, were prepared using Y 2 O 3 , SiO 2 , SiC, and Li 2 CO 3. This research investigated the effects of high temperatures, air oxidation, and water-oxygen corrosion on the phase compositions of YSOC ceramics. The influence of environmental factors on the synthesis and decomposition of yttrium silicate was analyzed. Moreover, the study explored the compatibility of different oxidation products with SiC. The results suggest that Y 2 SiO 5 and Y 2 Si 2 O 7 are formed through the low eutectic of SiO 2 , Y 2 O 3 , and Li 2 CO 3. The high SiO 2 content likely contributes to the relatively low formation temperature of Y 2 Si 2 O 7. In the oxidizing environment, Y 2 SiO 5 reacts with SiO 2 to produce Y 2 Si 2 O 7. Conversely, in the water vapor-containing atmosphere, Y 2 Si 2 O 7 undergoes hydrolysis to form Y 2 SiO 5. Y 2 Si 2 O 7 displays a reduced elastic modulus in comparison to SiC fibers and exhibits favorable physical and chemical compatibility with SiC fibers. However, the hydrolysis of Y 2 Si 2 O 7 may potentially affect the water-oxygen corrosion resistance of the ceramics. These findings will significantly advance research and enhance understanding of the water-oxygen corrosion behaviors of yttrium-containing matrix-modified composites. [ABSTRACT FROM AUTHOR]

Ammonia (NH 3) dissociation is of an initial and very important step during its combustion process. This study therefore systematically investigates the effect of reaction temperature (650–950 °C), fluidisation number (0.83–2.50) and static bed depth (0–25 mm) on NH 3 dissociation in a laboratory-scale Bubbling Fluidised Bed (BFB). By analysing the concentrations of H 2 and N 2 in the effluent using gas chromatography, results show that the conversion ratio of NH 3 in BFB was merely 0.26%–0.29% at 650 °C but increased significantly to 18.1%–25.3% at 950 °C. This highlights the importance of temperature in promoting NH 3 dissociation. However, as fluidisation number increased from 1.0 to 2.5, attributing to a decrease in gas – solid contact time, the conversion ratio of NH 3 decreased correspondingly from the highest 20.7%–5.7%. Moreover, as static bed depth increased from 15 mm to 25 mm, the conversion ratio of NH 3 increased slightly from 21.5% to 26.8%, both of which were found to be higher than that without bed particles. Clearly, NH 3 dissociation is enhanced by the bed material depth but is also dependent on the gas – solid contact time. In addition, by measuring the temperature distribution in the BFB reactor, a temperature drop of ca. 20 °C near the distributor was confirmed, showing a strong effect of endothermicity during NH 3 dissociation. These would provide an improved comprehension on the mechanisms of NH 3 dissociation and offer theoretical guidance for optimising the combustion processes in BFB burning NH 3. [Display omitted] • NH 3 dissociation at different temperatures and fluidisation numbers in BFB studied. • NH 3 conversion increased with temperature due to enhanced kinetic and heat transfer. • Increasing bed depth promotes NH 3 dissociation by increasing gas-solid contact time. • NH 3 conversion was the highest at incipient fluidisation but decreased at higher FN. • The endothermic NH 3 dissociation decreases bed temperature and hinders conversion. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to investigate the relationship between meteorological factors, specifically temperature and precipitation, and the incidence of appendicitis in Seoul, South Korea. Methods: Using data from the National Health Insurance Service spanning 2010–2020, the study analyzed 165,077 appendicitis cases in Seoul. Time series regression modeling with distributed-lag non-linear models was employed. Results: Regarding acute appendicitis and daily average temperature, the incidence rate ratio (IRR) showed an increasing trend from approximately − 10 °C to 10 °C. At temperatures above 10 °C, the increase was more gradual. The IRR approached a value close to 1 at temperatures below − 10 °C and above 30 °C. Both total and complicated appendicitis exhibited similar trends. Increased precipitation was negatively associated with the incidence of total acute appendicitis around the 50 mm/day range, but not with complicated appendicitis. Conclusions: The findings suggest that environmental factors, especially temperature, may play a role in the occurrence of appendicitis. This research underscores the potential health implications of global climate change and the need for further studies to understand the broader impacts of environmental changes on various diseases. [ABSTRACT FROM AUTHOR]

To investigate the effect of temperature on the compressive performance of laminated bamboo lumber (LBL), 198 specimens were tested in three loading directions (parallel to the grain and perpendicular to the grain in both flatwise and edgewise sections) under exposure to 11 different temperatures in the range −60°C to 200°C. Through the macroscopic failure modes summarised by damage characteristics and microscopic vascular bundles observed by scanning electron microscopy, the failure mechanisms of LBL under different temperatures was analysed. The average compressive strength of the specimens in the three loading directions (parallel, perpendicular flatwise and perpendicular edgewise) at 20°C was 45.07, 12.13 and 10.75 MPa, respectively. The compressive strength in the three directions increased by more than 80% at the lowest temperature (−60°C), while the loss of compressive strength exceeded 70% at the highest temperature (200°C). This was due to thinning of the bamboo cell walls at high temperature, ultimately resulting in the disappearance of the layered structure of cell walls and thus the loss of bearing capacity. An empirical formula was developed to calculate the temperature effect factor for compressive strength varying with temperature. [ABSTRACT FROM AUTHOR]

Energy transitions are knowledge-intensive processes where a multitude of actors are trying to cope with inevitable knowledge gaps, surprises, and uncertainties. In this context, we focus on two techno-physical phenomena that are gaining practical relevance with the expansion of wind and geothermal energy extraction, and are surrounded by significant unknowns: wake effects and temperature plumes. Both phenomena can potentially affect the efficiency of energy production, but the extent of their impact is not yet known. Based on 28 semi-structured interviews with experts in the fields of wind and geothermal energy, we explore how different central actors perceive and interpret non-knowledge of wake effects and temperature plumes, and how they deal with it. We show that there are strategies for either using non-knowledge as a basis for action or simply ignoring it and sweeping knowledge gaps under the rug. Both strategies serve the function of protecting agency and keeping things going. [ABSTRACT FROM AUTHOR]

Long-span bridges are subjected to wind and temperature actions. Wind action is generally the governing load of long-span bridges in design, while temperature action is also significant. Accurate separation of typhoon- and temperature-induced responses is thus necessary for in-depth investigation of their effects and comprehensive evaluation of structural performance. This paper separates the temperature- and typhoon-induced responses of the Qingzhou Bridge by using a unified global analysis approach. The field-monitored meteorological data and structural responses collected from the structural health monitoring system installed on the bridge are analyzed in detail, with emphasis on the comparison of those during typhoon Higos (Signal No. 9) and a typical sunny day after the typhoon. Results show that the quasi-static variation of displacement and stress responses are higher on a typical sunny day than those during the typhoon period, which is out of intuition. Through the unified analysis, the temperature-induced responses are calculated, and the typhoon-induced responses can be separated. The temperature- and typhoon-induced longitudinal displacement, mid-span deflection, and stress of the girder are compared. The temperature-induced response accounts for a large part of the total quasi-static recording either on a typical sunny day or during the typhoon period, whereas typhoon caused significant dynamic responses. The typhoon-induced quasi-static and dynamic responses are also in good agreement with the wind tunnel test results. This case study demonstrates the effectiveness of the unified global analysis in separating the temperature effect. [ABSTRACT FROM AUTHOR]

Coating materials and fluctuations in inlet temperature are crucial components of the encapsulation process, with both factors affecting the physical, chemical, and functional qualities. Therefore, this study aimed to determine the optimal properties of Jack Bean tempeh hydrolyzate using maltodextrin and Gum Arabic coating materials at a specific spray drying temperature. The experimental method consisted of 80% (w/w) maltodextrin, 20% (w/w) Gum Arabic, and a combination of both, with variations in inlet temperature at 140°C, 150°C, and 160°C. The results showed that 20% Gum Arabic treatment at a spray drying temperature of 150°C produced the best hydrolyzate characteristics of Jack Bean tempeh. Based on the SEM analysis, the morphology of the hydrolyzate particle had a spherical and wrinkled shape. Additionally, FTIR results showed no significant structural difference between the sample treatment and the uncoated control. [ABSTRACT FROM AUTHOR]

The effect of temperature, pressure, and specific solvent consumption on extraction yield from Leptocarpha rivularis stalks was studied using a Box–Behnken design. The effect of pressure on extraction yield was the most important, followed by temperature and specific solvent consumption (p ≤ 0.05). The extraction yield correlated (p ≤ 0.05) positively with the CO2 density. A diffusion model adequately described the cumulative extraction curve with the highest yield at the selected extraction condition. The inhibition of linoleic acid oxidation and the inhibition of lipoxygenase enzyme were higher in the supercritical (SC) extract than in the hydroethanolic extract. SC extraction could be used to isolate compounds from L. rivularis stalks with functional value. [ABSTRACT FROM AUTHOR]

Electrocaloric (EC) refrigeration offers superior energy-conversion efficiency, miniaturization, and environmental benefits compared to compression refrigeration. However, its practical application is limited by the challenge of aligning the adiabatic temperature change (Δ T) with the operational temperature range. In this study, we have tailored the EC characteristics of BaTiO 3 (BT)-based Ba(Ti 0.9 Sn 0.1)O 3 (BTS) ferroelectric ceramics using Bi(Mg 0.5 Ti 0.5)O 3 (BMT). We provide a comprehensive analysis of the microstructure, electrical properties, and EC behavior of the (1– x)BTS- x BMT system. Our results indicate that the incorporation of BMT establishes a broad platform in the dielectric spectrum while maintaining high polarization. This improvement potentially increases the electrocaloric effect (ECE) and expands the operating temperature range. Direct heat flux measurements reveal that the x = 0.02 composition achieves a maximum Δ T (Δ T max) of 0.41 K with a temperature span (T span) of 68 °C under an intermediate electric field of 50 kV/cm. Moreover, the x = 0.01 sample exhibits a room-temperature Δ T of 0.33 K and relatively good temperature stability within 30–130 °C. These findings indicate that chemical modification methods have the potential to optimize the cooling capacity of refrigerants. [ABSTRACT FROM AUTHOR]

Oleaginous microalgae have gained increasing attention as an alternative feedstock for biodiesel production due to the increasing demand of fuel, climate change, and global warming. This study aimed to isolate and screen robust microalgal strains from hot springs for cultivation in subtropical and tropical areas. The newly isolated oleaginous microalgae were cultivated at 30, 35 and 40 °C. Among mesophilic and thermophilic strains tested, Chlamydomonas sp. HP59 is considered the most robust strain as it showed high cell growth in a broad range of temperatures (30 - 40 °C), with the maximum dried cell weight at 40 °C. Un-optimal temperatures for cell growth did improve lipid content by 2 - 4 folds. To increase lipid production, the 2-stage cultivation, in which nitrogen-rich was applied to promote cell growth in the 1st stage and nitrogen-limitation was applied to stimulate lipid accumulation in the 2nd stage, was performed. The high temperature combined with nitrogen-limitation did improve lipid production by all microalgae. With this strategy, Chlamydomonas sp. HP59 showed the highest dried cell weight of 4.33 g/L and lipid production of 1.72 g/L. This study has shown the potential use of the newly isolated oleaginous microalgae from hot springs to be cultivated at high temperatures and under nitrogen-limited conditions for the production of biodiesel feedstocks. [ABSTRACT FROM AUTHOR]

Today, consumer demand for food safety, especially in fried foods, is increasing. In the first place, it is demanded to reduce the amount of food toxins, in particular toxins resulting from the thermal process such as acrylamide. This study aimed to examine the effect of different technological treatments on the optimisation of minimum acrylamide and maximum colour properties by applying the Taguchi approach in the production of chips. In this study, design of experiments, signal-to-noise (S/N) ratio, analysis of variance, and regression analysis methods were used to optimise the minimum acrylamide and redness (a*), maximum brightness (L*), and yellowness (b*) values. The optimal parameters for acrylamide were found to be 90 °C slice washing temperature, 175 °C frying temperature, and 175 s frying time. The optimal parameters for colour analysis were determined as 30 °C slice washing temperature, 175 °C frying temperature, and 175 s frying time. Analysis of variance showed that frying temperature and time had a significant (p < 0.05) effect on the results. It was determined that a decrease in frying temperature and time led to a decrease in the amount of acrylamide and redness and an increase in brightness and yellowness. According to the results of the analysis of variance, the most effective technological treatments were frying temperature with effect rates of 37.45% and 60.26% for acrylamide and L* values, respectively, and frying time with effect rates of 40.50% and 44.19% for a* and b* values, respectively. As a result of the study, through the Taguchi method, while quality features in chips were preserved, the amount of acrylamide was reduced. [ABSTRACT FROM AUTHOR]

The thermal-induced pore-water pressure and shear characteristics of lateritic clay under different temperature paths without drainage are studied through a series of temperature-controlled undrained triaxial shear tests with temperatures ranging from 5°C to 50°C. The effects of different temperature paths under undrained conditions on pore-water pressure and shear behavior are discussed. The results indicate that monotonic heating and multistage heating have equivalent effects on the accumulation of pore-water pressure when the initial temperature and target temperature are the same. The initial positive pore-water pressure induced by heating leads to a lower bearing capacity during the early stage of the shearing process. The secant elastic modulus (εa = 0.1%) shows a significant decrease with increasing temperature, suggesting that mechanical properties at small strains are influenced by temperature. However, undrained heating has no influence on the shear strength finally. Furthermore, under undrained conditions, temperature variations do not alter the unique relationships among void ratio, deviator stress, and mean effective stress. [ABSTRACT FROM AUTHOR]

This work examines the effect of temperature on the self-healing of asphalt mixture, and various laboratory tests were performed to find out qualitative and quantitative properties of asphalt material. Asphalt fatigue life and bending strength were determined using a three-point bending test and a four-point beam fatigue test. Test specimens were heated at various temperatures ranging from 20°C to 40°C for various periods, including the 20, 40, 60, 80, and 100 s. The strength recovery ratios at temperatures 20°C, 25°C, 30°C, 35°C, 40°C were 7%, 30%, 36%, 40%, 45%, respectively. The maximum healing index values for bitumen with penetration grades of 60/70 and 80/100 were 0.4 and 0.5 at temperatures between 37°C and 40°C. A 60 s period was chosen as the ideal period for achieving the highest recovery ratio for both bitumen specimens. It was observed that critical factor affecting the asphalt's capacity for self-healing is temperature, and the maximum healing index was found at temperatures between 37°C and 40°C. [ABSTRACT FROM AUTHOR]

Chloride transport is one of the most serious problems facing reinforced concrete structures, and coatings can effectively block the intrusion of chloride ions. In order to evaluate the resistance of coatings to chloride ion erosion more quickly and accurately, based on the transport mechanism of chloride and water in coated concrete, a two-dimensional mesoscale model of concrete containing coating, aggregate, and matrix was established in this paper. In response to the transport mechanism of chloride ions in coated concrete, a coupled convection–diffusion numerical model considering the binding effect of chloride, temperature effect, and hydration effect is established. The idealized service life conditions of the coating are introduced, and the influence of coating type, coating thickness, and coating service life on the distribution of erosive agents inside the coated concrete is analyzed. After analysis and research, it is recommended that coating concrete exposed to 3.5% NaCl erosion use a film-forming coating with an expected life of more than 10 years and a coating thickness of at least 1.5 mm, preferably chlorinated polyvinyl chloride (CPVC) and chlorinated polyethylene (CPE) coatings. [ABSTRACT FROM AUTHOR]

The effect of high temperature will trigger the evolution of a series of phase compositions and microstructures within metakaolin-fly ash-based geopolymers, resulting in changes in the deterioration of mechanical properties. To study the high-temperature resistance of metakaolin-fly ash-based geopolymers, the ratio of metakaolin and fly ash was adjusted. This article studied compressive strengths, visual appearance, mass loss ratio, permeability, products, and microstructure. The results showed that as the temperature increases, the compressive strength first increases and then decreases. The geopolymers have the highest compressive strength after exposure to temperatures of 200 °C. The change in compressive strength is determined by both the increase caused by the polymerization reaction and the decrease caused by microcracks. Moreover, metakaolin-fly ash-based geopolymers containing 75% metakaolin (GFMK-75) have the best high-temperature resistance. The residual compressive strengths of GFMK-75 after exposure to 200, 600, 800, and 1000 °C for 2 h are 183.1%, 95.2%, 75.8%, and 65.2%, respectively. Other analyses all confirmed the above conclusions. In summary, the residual compressive strength of metakaolin-fly ash-based geopolymers is highest after exposure to 200 °C, and GFMK-75 shows the best high-temperature resistance compared to others. The findings offer a theoretical foundation for the high-temperature resistance of metakaolin-fly ash-based geopolymers. [ABSTRACT FROM AUTHOR]

Cryopreservation of receptacles or fertilized eggs is the main method for the preservation of indoor germplasm resources for the economic seaweed Sargassum fusiforme. However, none of these methods can achieve long-term preservation of germplasm resources. The holdfast represents the asexual reproductive organ of S. fusiforme and has a dense tissue that can be regenerated into seedlings under suitable conditions. Therefore, in this study, the holdfast was used as the experimental material to analyze the effects of different temperatures (8 °C, 10 °C, 13 °C) and salinities (29‰, 24‰, 19‰, 14‰) on the preservation of S. fusiforme germplasm. The results showed that 29‰ and 14‰ were not suitable for the long-term preservation of holdfasts regardless of temperatures, since both photosynthesis and growth rates of the holdfast decreased after 30 days of preservation at these salinities. However, 8 °C and 19‰ were found to be suitable for the long-term in vitro preservation of holdfasts, with a survival time being as long as 120 days. During the experiment, the photosynthesis activity of the holdfast also displayed less fluctuation in this experimental condition than in the others. After 120 days, the content of malondialdehyde in the holdfasts was the lowest, and the morphology remained intact. 8 °C and 19‰ could be suitable for long-term indoor preservation of S. fusiforme. These findings might provide technical support for solving the problem associated with the difficulty of preserving the germplasm of superior strains in the breeding process. They might also have important significance for crossbreeding and for establishing a germplasm resource bank for S. fusiforme in the future. [ABSTRACT FROM AUTHOR]

The technology of post-larval farming is increasingly being valued by aquaculture farmers and enterprises. The objective of this study is to determine an appropriate temperature restriction mode through temperature training to achieve greater compensatory growth potential. We cultured PL whiteleg shrimp (Litopenaeus vannamei) at either low (25℃) or high (31℃) temperature for 20 days (restriction stage) and then transferred them to a control temperature (28℃) for 20 days (compensation stage). The compensatory growth observed under low temperature restriction showed that shrimp can recover and exhibit over-compensatory growth after growth restriction. Specific growth ratio and enzyme activity analyses indicated that the shrimp required 10 days or more to adapt to temperature stress. The relative expression levels of hsp60, tor, and s6k in the low temperature group were downregulated during the early stage of the restriction period, but were continually upregulated during the compensation period. This result indicates that although short-term restrictions may lead to growth retardation, growth will resume as the temperature recovers. When shrimp were challenged with Vibrio parahaemolyticus E1, the damage caused by infection after low temperature restriction and compensation was delayed and not severe. This indicates that the disease resistance of shrimp was improved after low temperature restriction. In contrast, shrimp in the high temperature group showed more severe damage than those in the control group at all time points after pathogen infection, indicating that high temperature restriction made the shrimp more susceptible to pathogenic Vibrio. Transcriptome analysis revealed abundant pathways related to energy metabolism, amino acid biosynthesis, protein synthesis, and cell growth in the low temperature restriction-recovery group, which highlighted the importance of optimizing the nutrient supply, especially protein and amino acid to enhance compensatory growth. In summary, after 20 days of low temperature training, PL shrimp exhibited significant compensatory growth, which not only promoted the growth, but also enhanced the body's resistance to V. parahaemolyticus. Therefore, this culture technique can be used for aquaculture practices in PL shrimp cultivation. [ABSTRACT FROM AUTHOR]

Brine shrimp Artemia is able to filter particulate substances non-selectively and continuously, and its filtration capacity is related to various environmental parameters as well as Artemia growth stage. In this study, the filter-feeding rate (FFR) of Artemia franciscana at different temperatures (20°C /25°C /30°C) and stocking densities (200/400/750/1000 ind./L at two earlier growth stages with the body length of 0.91 ± 0.05 mm and 1.53 ± 0.22 mm, respectively; 50/100/200 ind./L at two later growth stages with the body length of 4.72 ± 0.51 mm and 10.26 ± 0.46 mm, respectively) on three unicellular algae (Chlorella vulgaris, Porphyridium purpureum, Phaeodactylum tricornutum) and two sizes of polyethylene beads (30 μm and 50 μm) was determined at Artemia four growth stages. In total 144 combinations were tested. The results showed that the FFR was positively correlated with the ambient temperature and Artemia body length, while it was negatively correlated with the Artemia density and particle size. One way ANOVA analysis showed that ambient temperature, Artemia stocking density and particle size mostly had significant effects on FFR (P < 0.05). And the favorable filtration particle size of Artemia increased with its body length. The equation of FFR in function of temperature (T), Artemia body length (BL) and stocking density (SD), and particle size (PS) was obtained using multiple linear regression analysis: FFR = 0.487* BL + 0.067* T-0.01* SD-0.064* PS-1.508 (R2 = 0.513). Of these four variables, body length had the greatest effect on FFR, followed by ambient temperature, particle size and Artemia density. There were interactions among three factors (T, SD and PS) and the interactive degree varied with Artemia growth. The results of this study provide a valuable guidance for proper feeding in controlled Artemia production and standardization of feeding protocol for ecotoxicity and fundamental Artemia research. [ABSTRACT FROM AUTHOR]

The effect of temperature (15, 20, 25, 30, and 35 °C) on the ultrasonic degradation of sodium poly(styrene sulfonate) polyelectrolyte (5.10−3 g/ml) in aqueous NaCl solutions (2.75 m) was investigated. Using the thousands of data obtained by an online viscometer monitoring technique, the degradation kinetics, and the effect of temperature on this process were analyzed in detail with 12 theoretical models reported in the literature. The Giz, OHM, and Tang-Goto models were found to give good results, and these models were selected to evaluate the effect of temperature on the ultrasonic polymer degradation. The degradation constant and the limiting molecular weight at which no polymer chain scission occurs were found to decrease with increasing temperature for all models. Furthermore, modeling was performed using popular machine learning algorithms, such as Multilayer Perceptron, Adaptive Neuro-Fuzzy Inference System, Long Short-Term Memory, Gradient Boosting Regression, Light Gradient Boosting Machine, eXtreme Gradient Boosting Regressor, CatBoost, and Random Forest. The best results were obtained with the Long Short-Term Memory, a deep learning approach. In addition, optimization techniques, such as Particle Swarm Optimization, Genetic Algorithm, Artificial Bee Colony, Clustering, and Global Optimization Method based on a parabolic approach, were used to determine the optimum molecular weight evolution and degradation temperature. [ABSTRACT FROM AUTHOR]

In this work, the effect of deformation temperature on the microstructure, texture, and tensile properties of a Ti-6Al-4Zr-2Mo-6V (wt. %) alloy was systematically investigated. The whole samples were composed of an equiaxed α phase, a strip α phase, and a β transformed microstructure. The recrystallization area fraction increased with the increase of deformation temperature. The orientation distribution of a retained β phase was {001}β⟨110⟩β texture regardless of deformation temperature. The textured microstructure of an α phase was { 1 2 ¯ 10 } α ⟨ 10 1 ¯ 0 ⟩ α under the 810 and 840 °C condition. Additional { 11 2 ¯ 0 } α ⟨ 0001 ⟩ α texture was observed as the rolling temperature increased to 870 °C. The yield strength and the tensile strength of a rolling direction were lower than that of a transverse direction. The yield strength of a rolling direction and a transverse direction were both above 990 MPa when the deformation temperature was 840 °C. In summary, the present study provided theoretical guidance for the high strength titanium alloy applied for the marine engineering field. [ABSTRACT FROM AUTHOR]

The need for bearings in a variety of heavily loaded machines, including the influence of pressure and temperature, is generating increasing interest in studying the operating environment for magazine bearings. The purpose of this work is to develop a semi-analytical solution by introducing a new delta profile concept of the location of zero velocity gradients to obtain the simplest form of the equation of energy and Reynolds. In the journal bearing, assuming that journal is rotating and bearing is fixed, a hydrodynamic lubrication is modelled with the Power Law fluid. The lubricant temperature effect is examined under isothermal limits and the results obtained are much more realistic with the experimental results. [ABSTRACT FROM AUTHOR]