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Alloy composition and heat treatment are of paramount importance to determining alloy properties. Their control is of great importance for new alloy design and industrial fabrication control. A base alloy utilizing MX carbide is designed through a theory guided computational approach coupling a genetic algorithm with optimization criteria based on thermodynamic, kinetic and mechanical principles. The combined effects of 11 alloying elements (Al, C, Co, Cr, Cu, Mo, Nb, Ni, Si, Ti and V) are investigated in terms of the composition optimization criteria: the martensite start (Ms) temperature, the suppression of undesirable phases, the Cr concentration in the matrix and the potency of the precipitation strengthening contribution. The results show the concentration sensitivities of each component and also point out new potential composition domains for further strength increase. The aging temperature effect is studied and the aging temperature industrially followed is recovered.

This paper aims to evaluate the effect of temperature on impact damage resistance of glass/epoxy laminates. A series of impact tests were performed using an instrumented impact-testing machine at temperature ranging from -40°C to +80°C. The resulting impact damage was measured using back light method. The impact resistance parameters were employed to understand the damage resistance. It was observed that temperature has a little effect on the impact responses of composite laminates. The damage resistance of glass/epoxy laminates is somewhat deteriorated at two opposite extremes of the studied temperature range and this behavior is likely due to the property change of glass/epoxy laminates under extreme temperatures

We calculate the zero-temperature conductivity of bilayer graphene (BLG) impacted by Coulomb impurity scattering using four different screening models: unscreened, Thomas–Fermi (TF), overscreened and random phase approximation (RPA). We also calculate the conductivity and thermal conductance of BLG using TF, zero- and finite-temperature RPA screening functions. We find large differences between the results of the models and show that TF and finite-temperature RPA give similar results for diffusion thermopower S${}_d$. Using the finite-temperature RPA, we calculate temperature and density dependence of S${}_d$ in BLG on SiO₂, HfO₂ substrates and suspended BLG for different values of interlayer distance c and distance between the first layer and the substrate d.

The influences of temperature and cyclotron frequency of a magnetic field on the ground state energy and mean number of phonons (MNP) of strong-coupling magnetopolarons in an asymmetric Gaussian potential quantum well(AGPQW) are researched by employing the linear-combination operator method and the unitary transformation. It was demonstrated through the numerical calculations that the ground state energy and the MNP increase with higher magnetic field cyclotron frequencies and temperature. In addition, increasing of the barrier of asymmetric Gaussian potential (AGP) causes the ground state energy to decrease while increasing the MNP of magnetopolarons.

In this study, the ground state properties of strong-coupling polaron in RbCl quantum wells (QWs) by using double asymmetric confined potential were theoretically investigated based on effective mass approximation. Ground state binding energy (GSBE), ground state energy (GSE), vibrational frequency (VF), and mean LO phonon number (MLOPN) were obtained as functions of asymmetric confinement potential parameters in QWs by using the unitary transformation method and linear combination operator. GSBE, GSE, VF and MLOPN were found to be increasing functions of asymmetric semi-exponential confinement potential (ASECP) parameter $U_0$ and decreasing functions of parameter $\sigma$. GSE was rapidly increased with the increase of confinement strength. GSBE, GSE, VF and MLOPN increase as the increasing (decreasing) of anisotropic parabolic confinement potential strength (confinement length). In addition, the temperature effect was evaluated by using quantum statistical theory. With the increase of temperature, GSE and GSBE decreased while VF and MNLOP increased.

This study primarily aimed to conduct experimental research, focusing on examining the effects of various fly ash additive ratios, spanning from 0% to 1%, on the alterations in lubricating oil viscosity over a temperature range extending from 25°C to 85°C. The study employed viscosity measurements using the Rhotest VR2 viscometer on a commonly used lubricating oil, and carefully analyzed their behavior with varying fly ash additive concentration ratios. The results revealed that the addition of the fly ash additive increased the oil’s viscosity at all tested temperatures. The viscosity showed a proportional increase with the amount of additive up to a 0.5% weight ratio. Beyond this concentration, the viscosity began to decrease but remained higher compared to that without the additive, attributed to the thermal conductive properties of the additive’s high-hardness metal oxide particles. The viscosity of the oil mixture with a 0.5% additive ratio increases compared to the case without the additive at temperatures of 25°C, 40°C, 65°C, 75°C and 85°C, corresponding to 13.88%, 18.32%, 37.73%, 22.91% and 32.97%, respectively. These research findings provide crucial insights for fine-tuning lubricant formulations across a spectrum of applications, especially in scenarios where temperature fluctuations play a pivotal role in lubricant efficacy. By judiciously choosing the right proportion of fly ash additive, engineers and researchers can augment the lubricative attributes of oils and enhance their resilience under diverse thermal conditions. This includes factors such as increasing viscosity, load-carrying capacity and stiffness of the oil film. The result is a machinery operation that is not only more efficient but also more dependable.

Using the two-time Green's function method, we analyze the temperature effect on the famous Cirac and Zoller model. Formulas for the average number of different mode phonons and the deviation of its internal state from its ground state are derived. The influence of the internal state energy and trap frequency on the number of phonons is also discussed. The upper limit of temperature for regular quantum computation in the Cirac and Zoller model is obtained.

We study the temperature effect of bound polaron, which is strongly coupled to LO-phonon by using a variational method of the Pekar type in a triangular potential quantum dot (QD). The ground state energy was expressed as functions of the confinement length of QD, the Coulomb bound potential, the polar angle and the temperature. It is found that at low temperature, the influence of Coulomb bound potential and the confinement length of QD to the ground state energy of bound polaron play a leading role. At high temperature, the influence of temperature to the ground state energy of bound polaron is dominant.

On the condition of strong electron–LO phonon coupling in an asymmetric RbCl quantum dot (QD), the first excited state energy (FESE), the excitation energy (EE), and the transition frequency (TF) between the first excited ground states (FEGS) of the polaron are calculated by using the linear combination operator and the unitary transformation methods. The variation of the FESE, the EE and the TF with the temperature, the transverse and longitudinal confinement strengths (TLCS) of the QD are studied in detail. We find that the FESE, the EE and the TF decreases (increases) with increasing temperature when the temperature is in lower (higher) temperature regime. They are increasing functions of the TLCS. We find three ways to tune the FESE, the EE and the TF via controlling the temperature and the TLCS.

The ground state energy E₀, first excited state energy E₁, excitation energy ΔE and oscillating period t of the polaron are calculated by using the linear combination operator and the unitary transformation methods. The variation of the above quantities with the temperature T and the potential well width L, we found that E₀, E₁ and ΔE all increase with increasing T and decrease with increasing L, but t changes with T and L in the opposite.

DNA condensation by multivalent cations has been extensively studied using single molecule experiment methods. To detect temperature effect on DNA condensation at the single molecule level, a strong correlation model was developed to investigate the behavior of DNA with self-interactions under constant tension. The simulation results are in line with the single molecule experiment that the kinetics of DNA condensation take on discontinuous and stepwise manner regardless of the toroid or rod-like conformation. By incorporating the temperature dependence of DNA persistence length into the strong correlation model, the temperature effect on DNA condensation is identified. The results indicate that condensed DNA conformations at single molecule level become more compact with increasing temperature.

With molecular dynamics simulations, the growth of face-centered-cubic nanocrystalline materials Ni and Ni₃Al has been studied. It is found that grain-rotation induced grain coalescence and curvature-driven grain-boundary migration are dominant mechanisms in the nanograin growth. A detailed comparison of the nanograin growth between the two systems is discussed in terms of grain rotation and grain sliding. We also study the temperature effect and the size effect in the nanograin growth. The tendency of twinning in the nanograin growth is discussed. It is found that in Ni₃Al, it seems more possible for nanograins to grow into twin-like structures than single crystal unless at very high temperatures.

This paper utilized the methods of linear combination and unitary transformation to evaluate the vibrational frequency (VF) and ground state binding energy (GSBE) of a strong-coupling magnetopolaron in an asymmetrical Gaussian potential quantum well (AGPQW), and the effects of the temperature on these physical quantities were studied through quantum statistical theory. The changes of the VF and GSBE versus temperature and cyclotron frequency (CF) in a magnetic field were discussed. The numerical calculations revealed that with the increase of temperature, the VF and GSBE also increased. Meanwhile, the numerical results show that the VF increases with the increase of the CF. However, the GSBE versus the CF has different changing properties.

The importance of the kinetic study of endoplasmatic calcium ion channels in different intracellular processes is known today. Although there are few experimental reports on the temperature dependency of IP3R channel functions, we did not find any detailed theoretical study on this subject. For this purpose, we used a modified Gillespie algorithm to investigate the effect of temperature on the conditions affecting the open state of a single subunit of the De Young-Keizer (DYK) model. Population of the states was considered as the subject of fluctuation. Key features of the channel, such as bell-shaped dependency of open probability to the Calcium concentrations were modeled at different temperatures, too. The range of temperature variation was selected by regarding the experimental data on IP3R channel.

By increasing the temperature, we had the very slow time domains (t: 10^-1s) and the much slower time domains (t: 10⁰s) in addition to other time domains, which could be seen as new time categories in InsP3R studies, and so the results were reported in these time domains, as well.

We found out that increase in temperature declined the open probability in some concentrations of Ca²⁺ and/or IP3. Also, by introducing the intensity graphs, broadening of the range of fluctuations and lowering of the order of frequency of fluctuations for the population of each state were observed due to the temperature increments.

The temperature effects on the activation and inactivation states of the channel were studied in the framework of the reaction paths. We did not find similar paths at different time domains; several paths observed which were totally different all together. These time-dependent reaction paths are also depending on the Ca²⁺ and/or the IP3 concentrations. So, one can predict the most probable reaction paths at different concentrations and temperatures and also determine which kind of the path it is; a path for closing the channel or a path to open it.

Finally, the temperature effects on the calcium inhibited states were studied. We found out that calcium ion inhibitions were shifted to lower calcium concentration by increasing the temperature. The results suggests that inhibiting role of calcium is not only [Ca²⁺] and/or [IP3] dependent, but also temperature dependent.

A huge number of data can be obtained continuously from a number of sensors in long-term structural health monitoring (SHM). Different sets of data measured at different times may lead to inconsistent monitoring results. In addition, structural responses vary with the changing environmental conditions, particularly temperature. The variation in structural responses caused by temperature changes may mask the variation caused by structural damages. Integration and interpretation of various types of data are critical to the effective use of SHM systems for structural condition assessment and damage detection. A data fusion-based damage detection approach under varying temperature conditions is presented. The Bayesian-based damage detection technique, in which both temperature and structural parameters are the variables of the modal properties (frequencies and mode shapes), is developed. Accordingly, the probability density functions of the modal data are derived for damage detection. The damage detection results from each set of modal data and temperature data may be inconsistent because of uncertainties. The Dempster–Shafer (D–S) evidence theory is then employed to integrate the individual damage detection results from the different data sets at different times to obtain a consistent decision. An experiment on a two-story portal frame is conducted to demonstrate the effectiveness of the proposed method, with consideration on model uncertainty, measurement noise, and temperature effect. The damage detection results obtained by combining the damage basic probability assignments from each set of test data are more accurate than those obtained from each test data separately. Eliminating the temperature effect on the vibration properties can improve the damage detection accuracy. In particular, the proposed technique can detect even the slightest damage that is not detected by common damage detection methods in which the temperature effect is not eliminated.

In vibration-based structural damage detection, it is necessary to discriminate the variation of structural properties due to environmental changes from those caused by structural damages. The present paper aims to investigate the temperature effect on vibration-based structural damage detection in which the vibration data are measured under varying temperature conditions. A simply-supported slab was tested in laboratory to extract the vibration properties with modal testing. The slab was then damaged and the modal testing was conducted again, in which the temperature varied. The modal data measured under different temperature conditions were used to detect the damage with a two-stage model updating technique. Some damage was falsely detected if the temperature variation was not considered. Natural frequencies were then corrected to those under the same temperature conditions according to the relation between the temperature and material modulus. It is shown that all of the damaged elements can be accurately identified.

This paper is concerned with the temperature effect on the vibration of a cable-stayed beam. The thermal effect is considered by using two non-dimensional factors for the cable tension force and sag. The nonlinear in-plane and out-of-plane vibration equations of motion of the cable-stayed beam with thermal effect are derived by using the extended Hamilton’s principle. Eigenvalue analysis is performed to obtain closed-form eigenvalue solutions. It is shown that the effect of temperature variation plays a dominant role on the vibration behavior of the cable-stayed beam, and the effect is closely related with the initial tension force and the stiffness ratio. As to the in-plane motion, both positive and negative correlations between the temperature variations and natural frequencies are found, which depend on the mode order and the stiffness ratio of the cable-stayed beam. However, as to the out-of-plane motion, there only exist negative correlations between the temperature variation and natural frequencies, and the effect of temperature dropping condition seems more obvious. Moreover, both for the in-plane and out-of-plane motions, the locations of veering points between two natural frequencies are shifted under the thermal effect, which can significantly affect the internal resonance between different modes of the cable-stayed beam.

This study investigates the relationship between the temperature and the modal frequencies of bridges through a series of model experiments using a concrete continuous beam bridge model and a steel cable-stayed bridge model in a controlled-temperature chamber. The experimental results show that, for a given boundary condition and in the absence of freezing, a change in temperature affects the structural frequencies of the bridge as it alters the elastic modulus of the bridge materials. The structural frequency tends to linearly decrease with increasing temperature and with the decrease in the frequency of steel bridges smaller than that of concrete bridges. For the particular case of wet concrete bridges, the temperature dependencies of modal frequencies vary dramatically near the freezing point, which is attributable to the freeze–thaw process of concrete pore water. The effect of air humidity on structural frequency is less significant than that of temperature when the boundary conditions remain unchanged. Furthermore, temperature changes may alter the boundary conditions of bridges, thereby affecting the structural frequencies.

Applying Kinetic Monte Carlo (KMC) technique, we investigated the influence of temperature and step-width on the step-flow growth of a (2D + 1) semiconductor-like uniform-spacing stepped model with inverse Ehrlich–Schwoebel (iES) barrier. The relation between diffusion length (R) and half of step width (L/2) was established to characterize the transition temperature T_c for switching between the random deposition growth and step-flow growth on surface. When temperature is lower than T_c, the surface growth mode is dominated by random deposition growth. As temperature approaches to T_c, the surface growth mode gradually switches to step-flow growth. However, only when the temperature is much higher than T_c, the random deposition growth is completely replaced by the step-flow growth. It is found that the step-width effect has a profound influence on surface growth mode in the transition region. The surface morphology undergoes a kinetic step-flow growth to form step-edge aggregation by either increasing temperature or decreasing the step width.

Using two-time Green's function we analyze the effect of temperature on the Mølmer and Sørensen (M–S) model of cold trapped ion quantum computer. A formula for the deviation of an internal state from its ground state is derived in the first-order approximation. The fluctuation of internal state caused by thermal motion is also discussed. The deviation of internal state when different trap parameters changes with the temperature are given too. The upper temperature limit for regular quantum computation is obtained and our result is in agreement with experiment.