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The urban thermal environment is impacted by changes in urban landscape patterns resulting from urban expansion and seasonal variation. In order to cope effectively with urban heat island (UHI) effects and improve the urban living environment and microclimate, an analysis of the heating effect of impervious surface areas (ISA) and the cooling effects of vegetation is needed. In this study, Landsat 8 data in four seasons were used to derive the percent ISA and fractional vegetation cover (FVC) by spectral unmixing and to retrieve the land surface temperature (LST) from the radiative transfer equation (RTE). The percent ISA and FVC were divided into four different categories based on ranges 0–25%, 25–50%, 50–75%, and 75–100%. The LST with percent ISA and FVC were used to calculate the surface heating rate (SHR) and surface cooling rate (SCR). Finally, in order to analyze the heating effect of ISA and the cooling effect of vegetation, the variations of LST with SHR and SCR were compared between different percent ISA and FVC categories in the four seasons. The results showed the following: (1) In summer, SHR decreases as percent ISA increases and SCR increases as FVC increases in the study area. (2) Unlike the dependence of LST on percent ISA and FVC, the trends of SHR/SCR as a function of percent ISA/FVC are more complex for different value ranges, especially in spring and autumn. (3) The SHR (heating capacity) decreases with increasing percent ISA in autumn. However, the SCR (cooling capacity) decreases with increasing FVC, except in summer. This study shows that our methodology to analyze the variation and change trends of SHR, SCR, and LST based on different ISA and FVC categories in different seasons can be used to interpret urban ISA and vegetation cover, as well as their heating and cooling effects on the urban thermal environment. This analytical method provides an important insight into analyzing the urban landscape patterns and thermal environment. It is also helpful for urban planning and mitigating UHI.

Determining exhumation and cooling rates of regional metamorphic rocks is essential for deciphering orogenic dynamics and heat transport in the Earth's crust. Although radiometric dating is commonly used, its temporal resolution becomes coarser for older rocks, limiting its ability to resolve Precambrian metamorphic timescales. Diffusion chronometry, based on mineral zoning, offers age-independent temporal resolution but is affected by uncertainties in pressure–temperature conditions and diffusion coefficients, which have not been fully evaluated in Paleoproterozoic or older orogens. This study integrated Monte Carlo-based garnet Fe–Mg-Ca-Mn diffusion simulations with phase equilibria modeling to quantify exhumation and cooling rates of pelitic granulites from the Paleoproterozoic Jiao–Liao–Ji orogen, explicitly addressing uncertainty propagation. The granulites record peak pressures of 13–14 kbar at 850–870 °C, followed by heating during decompression to ultra-high-temperature conditions (~ 940 °C, ~ 6.5 kbar) within 2–9 Myr at ca. 1.86 Ga. Subsequent cooling to ~ 5 kbar and ~ 600 °C is nonlinear, with rapid cooling (up to 148 °C/Myr) above 800 °C, and slower cooling (~ 5 °C/Myr) below 700–600 °C. These diffusion-based timescales and rates, with uncertainties of 0.3–0.5 orders of magnitude (1σ), outperform current in situ radioisotope geochronology methods, providing refined constraints on Orosirian geodynamics. The heating during decompression and subsequent nonlinear cooling suggest potential parallels with modern mantle upwellings and extensional tectonics; slower cooling and exhumation rates obtained in this study (when compared to modern systems) potentially reflects a weaker Paleoproterozoic lithosphere. This research highlights the power of diffusion chronometry for understanding of early Earth history.

To enhance the water pre-cooling rate, postharvest quality, and prolong the shelf life of fruit and vegetables, static magnetic field-assisted water pre-cooling technology (SM-WPT) was proposed. The study investigated the effects of static magnetic field (0–100 Gs) on the cherry cooling rate during water pre-cooling process and evaluated the physicochemical properties during its 21-day storage ( T  = 4 ℃). Moreover, the analytical hierarchy process combined with entropy weight method (AHP-EWM) was utilized to analyze the optimal parameters of SM-WPT for preserving cherries. Results demonstrated that SM-WPT significantly prevented the deterioration of postharvest cherry quality during storage. The cherry for the SM40 group (40 Gs) reduced the cooling time by up to 40% compared to non-magnetic field treatment, alleviated changes in color difference and weight loss with 22.70% and 12.90%, respectively, and an obvious decrease in respiration rate and decay rate. Meanwhile, the SM80 group (80 Gs) was the best treatment for improving antioxidant enzyme activity and inhibiting malondialdehyde accumulation. The AHP-EWM comprehensive evaluation indicated that the SM40 group had the best overall preservation effect on cherries.

In this paper, the solidification characteristics of Al-Ti alloys and the precipitation behavior of Al 3 Ti phases at different Ti contents and cooling rates were investigated by cooling curve thermal analysis. By heating the Al- x Ti ( x  = 1, 2, 3) alloys melt to 1100 °C and cooling it under near-equilibrium solidification and non-equilibrium solidification conditions, the precipitation growth characteristics of the Al 3 Ti phase were analyzed under each solidification condition. The results demonstrated that the precipitation temperatures of the Al 3 Ti phase in Al- x Ti ( x  = 1, 2, 3) alloys increased from 774.65 to 920.26 °C with the increase in Ti content from 1 to 3 wt.% under the condition of near-equilibrium solidification. Under the condition of non-equilibrium solidification, the volume fraction of the Al 3 Ti phase and the size of the Al 3 Ti phase formed by solidification at the mold temperature of 200 °C were larger than those at the mold temperature of room temperature. With the increase in Ti content, the volume fraction of the Al 3 Ti phase increased gradually, and the size of the Al 3 Ti phase increased first and then decreased, the yield strength and the tensile strength of the Al- x Ti ( x  = 1, 2, 3) alloys increased, which reached the maximum values of 82.15 and 106.12 MPa at a Ti content of 3 wt.% under the condition of room-temperature mold casting. The morphology of the Al 3 Ti phase gradually changed from petal-like to block-like, needle-like, and finally to short needle-like. During the solidification process, Al- x Ti ( x  = 1, 2, 3) alloys preferentially formed Al 3 Ti precipitated phases. As the heterogeneous nucleation core, the Al 3 Ti phase greatly promoted the nucleation of α-Al, resulting in a decrease in grain size, and the grain shape tended to be equiaxed.

The unknown cooling-rate history of natural silicate melts can be investigated using differential scanning heat capacity measurements together with the limiting fictive temperature analysis calculation. There are a range of processes occurring during cooling and re-heating of natural samples which influence the calculation of the limiting fictive temperature and, therefore, the calculated cooling-rate of the sample. These processes occur at the extremes of slow cooling and fast quenching. The annealing of a sample at a temperature below the glass transition temperature upon cooling results in the subsequent determination of cooling-rates which are up to orders of magnitude too low. In contrast, the internal stresses associated with the faster cooling of obsidian in air result in an added exothermic signal in the heat capacity trace which results in an overestimation of cooling-rate. To calculate cooling-rate of glass using the fictive temperature method, it is necessary to create a calibration curve determined using known cooling- and heating-rates. The calculated unknown cooling-rate of the sample is affected by the magnitude of mismatch between the original cooling-rate and the laboratory heating-rate when using the matched cooling-/heating-rate method to derive a fictive temperature/cooling-rate calibration curve. Cooling-rates slower than the laboratory heating-rate will be overestimated, while cooling-rates faster than the laboratory heating-rate are underestimated. Each of these sources of error in the calculation of cooling-rate of glass materials—annealing, stress release and matched cooling/heating-rate calibration—can affect the calculated cooling-rate by factor of 10 or more.

Convective updrafts are one of the main characteristics of convective clouds, responsible for the convective mass flux and the redistribution of energy and condensate in the atmosphere. During the early stages of their lifecycle, convective clouds experience rapid cloud-top ascent manifested by a decrease in the geostationary IR brightness temperature (TBIR). Under the assumption that the convective cloud top behaves like a black body, the ascent rate of the convective cloud top can be estimated as (∂TBIR∂t), and it can be used to infer the near cloud-top convective updraft. The temporal resolution of the geostationary IR measurements and non-uniform beam-filling effects can influence the convective updraft estimation. However, the main shortcoming until today was the lack of independent verification of the strength of the convective updraft. Here, Doppler radar observations from the ESCAPE and TRACER field experiments provide independent estimates of the convective updraft velocity at higher spatiotemporal resolution throughout the convective core column and can be used to evaluate the updraft velocity estimates from the IR cooling rate for limited samples. Isolated convective cells were tracked with dedicated radar (RHIs and PPIs) scans throughout their lifecycle. Radial Doppler velocity measurements near the convective cloud top are used to provide estimates of convective updrafts. These data are compared with the geostationary IR and VIS channels (from the GOES satellite) to characterize the convection evolution and lifecycle based on cloud-top cooling rates.

Understanding the exhumation of middle to lower crustal rocks is of utmost importance to unravel intracrustal mass transfer processes during orogenic build-up. The Figueira de Castelo Rodrigo–Lumbrales Anatectic Complex (FCR–LAC) is located within the autochthonous terrane of the Variscan Central Iberian Zone and is an example of the association between S-type granites and migmatites. The anatectic complex contacts to the north and south with low-grade metamorphic units through the Huebra and Juzbado–Penalva do Castelo shear zones, respectively. Integration of new U–Pb zircon and apatite age data allowed us to obtain Variscan crystallization ages, inherited zircon ages and unprecedented cooling rates for different facies of the FCR–LAC granites. The zircon crystallization ages mostly cluster around 313–317 Ma for the syn-tectonic granites, whereas the dated late-tectonic granite provided an age of 300 Ma. The cooling rates range from 13 to 35 °C Ma−1, which implies fast exhumation (0.3–0.84 mm a−1) and shallow emplacement (ca. 8 km deep), compatible with exhumation facilitated by large crustal-scale shear zones. Inherited zircon in the granites reveals melting of Cadomian metasediments (650–550 Ma), Upper Cambrian–Lower Ordovician (495–470 Ma) metaigneous rocks (Ollo de Sapo formation) and of minor older components, suggesting protolith affinity with the Northern Domain of the Central Iberian Zone.

The effect of cooling rate on thermoplasticity of ni base superalloy GH4151 during thermal deformation was studied. Several different treatments were used to obtain γ′ phases of different sizes and shapes. The hot tensile and hot compression tests were carried out, and the microstructure was studied in detail by scanning electron microscopy and transmission electron microscopy to determine the microscopic mechanism. The results show that the volume fraction of large γ’ phase increased with decreasing cooling rate. The slowly cooled material exhibits lower resistance to deformation due to more obvious softening behavior. The sample with slow cooling contains coarse γ′ phase and broaden γ-γ’ channel. The locations around broaden γ-γ’ channel were accumulated during deformation, which caused a high level of stored energy, and thus dynamic recrystallization (DRX) is promoted, and obvious softening behavior was displayed.

The paper presents a follow-up on the subject of the use of thermal analysis for the generation of fraction solid evolution in cast alloys, particularly in aluminum—silicon alloys. It discusses in detail the importance of correctly determining the characteristic temperatures of the cooling curve, including the beginning of solidification, the eutectic temperature, and the end of solidification. It demonstrates the importance of the smoothing techniques applied to the experimentally recorded temperature (cooling curve). Newtonian and Fourier analyses are used to generate the evolution of fraction of solid and the latent heat on cups of different diameters, to assess the effect of cooling rate for Al-7.5%Si alloys. Calculation results are compared with the literature data. It was found that the maximum temperature of the alloy in the cup affected the overall results.

This paper extends our previous work to investigate the effect of heat treatment on the microstructure of Ti-6Al-4V fabricated by selective laser melting. A post-heat treatment at 930 °C for 15 min followed by three cooling rates before and after hot isostatic pressing (HIP) treatment was applied. The findings illustrated that the microstructure of the quenched samples before the HIP treatment was characterized by a mixture of α + α′ phase with a microhardness value of 336 ± 6 HV0.3. Air cooling produced a structure dominated by the α phase, with ~ 7.5% of the β phase and a microhardness value of about 330 ± 4 HV0.3. Furnace cooling led to a mixture of α phase and ~ 17% of the β phase and hardness of 327 ± 6 HV0.3. After HIP followed by post-heat treatment, acicular α′ martensite with microhardness value 377 ± 2 HV0.3 dominated the quenched specimen microstructure. Following air cooling, the microstructure consisted of a mixture of α-lamella and β with some needles of the α with a microhardness value of 336 ± 3 HV0.3. In the case of the furnace cooling, a complete transformation of β to a mixture of α + β phase was observed. The β volume fraction formed in the microstructure was estimated at ~ 8.5%, having microhardness 322 ± 4 HV0.3. Reasons for such behaviors are discussed.