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Temperature increases are associated with an intensification of heavy sub‐daily extreme rainfall by approximately 7% per °C, in accordance with the Clausius‐Clapeyron (CC) relation. As a result of this intensification, there are concerns regarding the increased frequency and magnitude of floods in small to medium‐sized catchments. The high‐resolution two‐dimensional weather generator (WG), AWE‐GEN‐2d, offers an ideal tool to simulate the climate variables required to assess the catchment‐scale hydrological response at high resolution. However, it lacked an explicit representation of the relationship between temperature and precipitation that can mimic the CC relationship. Therefore, we introduce a newly revised version of the model, named AWE‐GEN‐2d‐CC, designed to mirror the observed CC scaling by conditioning the simulation of precipitation properties (intensity and area) on temperature. We demonstrate the model's efficacy in representing future extreme rainfall by simulating their potential impact on the hydrological response of a mountainous catchment in the Swiss Alps. Based on observations and future climate model projections, AWE‐GEN‐2d‐CC was used to generate large ensembles of present and end‐of‐century climate data at hourly and 2‐km resolutions, used subsequently as input to Topkapi‐ETH, a physically‐based, distributed hydrological model. The new version of the WG successfully mimics the CC scaling of heavy rainfall, leading to an intensification of short‐duration heavy rainfall in future climates, in contrast with the results obtained using the original model. This allows for a more realistic assessment of future rainfall impact on hydrological response, which, in the demonstration application, shows a modulated effect even for short durations. Plain Language Summary: As global temperatures continue to rise, so does the intensity of heavy rainfall, which can lead to increased flooding in small to medium‐sized areas. The challenge is predicting not only how heavy rainfall will intensify at a specific point, but also how it is distributed over a catchment area. The AWE‐GEN‐2d model proved to be an effective tool in this respect. We introduce a new version of that model, called AWE‐GEN‐2d‐CC, which explicitly considers the relationship between temperature and rainfall. We tested our model on a mountainous area in the Swiss Alps, using past observations and future climate model projections, and found that the model can successfully predict heavy rainfall intensification in the future, especially for short, intense bursts of rain. This improves the plausibility of the results compared to those obtained with the older version of the model. Despite the predicted increase in heavy rainfall, we found the effect on river flows in the catchment was less drastic. Our study highlights the importance of accurately modeling the impact of temperature on rainfall. In areas prone to high‐intensity storms, our model can assist stakeholders in preparing for future weather extremes. Key Points: A new version of the AWE‐GEN‐2d weather generator model is presentedThe new model explicitly simulates the temperature dependency of extreme precipitation, enabling a realistic simulation of future extremesA climate change hydrological impact study over an alpine catchment is presented [ABSTRACT FROM AUTHOR]

We present a detailed overview of the calculation of the enthalpy of dissociation of structure II pure propane or mixed methane + propane hydrates, focussing primarily on methods that are based on either the Clausius-Clapeyron equation or the direct calculation of the enthalpies of all the components that are involved in the hydrate dissociation reaction. Molecular dynamics simulations are used extensively in order to calculate the enthalpies and molar volumes of water, methane, propane, and the sII mixed hydrate (with variant degree of occupancy) at pressure and temperature conditions along the three-phase (Hydrate–Liquid water–Vapor or Hydrate–Liquid water–Liquid hydrocarbon) equilibrium line. [ABSTRACT FROM AUTHOR]

There is an urgent need for new CO2 adsorbents to overcome the rapidly increasing CO2 pollution. New CuO@UiO-67 composites were prepared by encapsulating CuO nanoparticles (NPs) in the shallow pore channels of UiO-67 through postsynthetic exchange (PSE) to form a core–shell structure. The composites were characterized via TEM, XRD, and BET analyses, and single component adsorption isotherm measurements of CO2, CH4 and N2 were performed at different temperatures. The selectivities of CO2/CH4 and CO2/N2 and the isosteric heats of CO2 adsorption were estimated based on the ideal adsorption solution theory (IAST) and the Clausius–Clapeyron equation, respectively. The highest CO2 uptake of CuO@UiO-67 was achieved at 273 K and 100 kPa with 61.9 cc g−1, which was twice that of parent UiO-67. The significant increase in CO2 uptake was not only due to the introduction of CuO NPs in the pore channel of CuO@UiO-67, but also due to the new open nitrogen sites due to ligand substitution. The adsorption selectivities of CO2/CH4 and CO2/N2 at 298 K and 100 kPa were 9.2 and 54.3, respectively. Furthermore, CuO@UiO-67 could efficiently separate the CO2/N2 mixture under a dynamic flow condition. These excellent properties suggest that the CuO@UiO-67 composite is a promising and efficient CO2 adsorbent material. This study lays a solid foundation for metal oxide-modified MOFs and is a great contribution to the preparation of new adsorbents. [ABSTRACT FROM AUTHOR]

Experiments on determination of the sorption isotherms of the heart of a palm at different temperatures have been performed. Some mathematical models, available in the literature, were used to predict the hygroscopic behavior of the palm heart. The thermodynamic properties of the palm heart, such as its isosteric heat of sorption, were determined using the Clausius–Clapeyron equation, and the shelf life of the palm heart was calculated using the Heiss–Eichner prediction model equations with regard for the storage conditions of this product and the requirements for its packaging. The results obtained can be used for optimization of the methods of drying and preservation of palm hearts, which is essential for the enhancement of their quality and the successful promotion of them in the international market. [ABSTRACT FROM AUTHOR]

We studied the phase diagram for the TIP4P/Ice water model using enhanced sampling molecular dynamics simulations. Our approach is based on the calculation of ice–liquid free energy differences from biased coexistence simulations that reversibly sample the melting and growth of layers of ice. We computed a total of 19 melting points for five different ice polymorphs, which are in excellent agreement with the melting lines obtained from the integration of the Clausius–Clapeyron equation. For proton-ordered and fully proton-disordered ice phases, the results are in very good agreement with previous calculations based on thermodynamic integration. For the partially proton-disordered ice III, we find a large increase in stability that is in line with previous observations using direct coexistence simulations for the TIP4P/2005 model. This issue highlights the robustness of the approach employed here for ice polymorphs with diverse degrees of proton disorder. Our approach is general and can be applied to the calculation of other complex phase diagrams. [ABSTRACT FROM AUTHOR]

By combining interface-pinning simulations with numerical integration of the Clausius–Clapeyron equation, we accurately determine the melting-line coexistence pressure and fluid/crystal densities of the Weeks–Chandler–Andersen system, covering four decades of temperature. The data are used for comparing the melting-line predictions of the Boltzmann, Andersen–Weeks–Chandler, Barker–Henderson, and Stillinger hard-sphere approximations. The Andersen–Weeks–Chandler and Barker–Henderson theories give the most accurate predictions, and they both work excellently in the zero-temperature limit for which analytical expressions are derived here. [ABSTRACT FROM AUTHOR]

The adsorption of acetamide on low density amorphous (LDA) ice is investigated by grand canonical Monte Carlo computer simulations at the temperatures 50, 100, and 200 K, characteristic of certain domains of the interstellar medium (ISM). We found that the relative importance of the acetamide–acetamide H-bonds with respect to the acetamide–water ones increases with decreasing temperature. Thus, with decreasing temperature, the existence of the stable monolayer, characterizing the adsorption at 200 K, is gradually replaced by the occurrence of marked multilayer adsorption, preceding even the saturation of the first layer at 50 K. While isolated acetamide molecules prefer to lay parallel to the ice surface to maximize their H-bonding with the surface water molecules, this orientational preference undergoes a marked change upon saturation of the first layer due to increasing competition of the adsorbed molecules for H-bonds with water and to the possibility of their H-bond formation with each other. As a result, molecules stay preferentially perpendicular to the ice surface in the saturated monolayer. The chemical potential value corresponding to the point of condensation is found to decrease linearly with increasing temperature. We provide, in analogy with the Clausius–Clapeyron equation, a thermodynamic explanation of this behavior and estimate the molar entropy of condensed phase acetamide to be 34.0 J/mol K. For the surface concentration of the saturated monolayer, we obtain the value 9.1 ± 0.8 µmol/m2, while the heat of adsorption at infinitely low surface coverage is estimated to be −67.8 ± 3.0 kJ/mol. Our results indicate that the interstellar formation of peptide chains through acetamide molecules, occurring at the surface of LDA ice, might well be a plausible process in the cold (i.e., below 50 K) domains of the ISM; however, it is a rather unlikely scenario in its higher temperature (i.e., 100–200 K) domains. [ABSTRACT FROM AUTHOR]

Projections of precipitation extremes over land are crucial for socioeconomic risk assessments, yet model discrepancies limit their application. Here we use a pattern-filtering technique to identify low-frequency changes in individual members of a multimodel ensemble to assess discrepancies across models in the projected pattern and magnitude of change. Specifically, we apply low-frequency component analysis (LFCA) to the intensity and frequency of daily precipitation extremes over land in 21 CMIP-6 models. LFCA brings modest but statistically significant improvements in the agreement between models in the spatial pattern of projected change, particularly in scenarios with weak greenhouse forcing. Moreover, we show that LFCA facilitates a robust identification of the rates at which increasing precipitation extremes scale with global temperature change within individual ensemble members. While these rates approximately match expectations from the Clausius-Clapeyron relation on average across models, individual models exhibit considerable and significant differences. Monte Carlo simulations indicate that these differences contribute to uncertainty in the magnitude of projected change at least as much as differences in the climate sensitivity. Last, we compare these scaling rates with those identified from observational products, demonstrating that virtually all climate models significantly underestimate the rates at which increases in precipitation extremes have scaled with global temperatures historically. Constraining projections with observations therefore amplifies the projected intensification of precipitation extremes as well as reducing the relative error of their distribution. [ABSTRACT FROM AUTHOR]

The Radiative‐Convective Equilibrium Model Intercomparison Project (RCEMIP) exhibits a large spread in the simulated climate across models, including in profiles of buoyancy and relative humidity. Here we use simple theory to understand the control of stability, relative humidity, and their responses to warming. Across the RCEMIP ensemble, temperature profiles are systematically cooler than a moist adiabat, and convective available potential energy (CAPE) increases with warming at a rate greater than that expected from the Clausius‐Clapeyron relation. There is higher CAPE (greater instability) in models that are on average moister in the lower‐troposphere. To more explicitly evaluate the drivers of the intermodel spread, we use simple theory to estimate values of entrainment and precipitation efficiency (PE) given the simulated values of CAPE and lower‐tropospheric relative humidity. We then decompose the intermodel spread in CAPE and relative humidity (and their responses to warming) into contributions from variability in entrainment, PE, the temperature of the convecting top, and the inverse water vapor scale height. Model‐to‐model variation in entrainment is a dominant source of intermodel spread in CAPE and its changes with warming, while variation in PE is the dominant source of intermodel spread in relative humidity. We also decompose the magnitude of the CAPE increase with warming and find that atmospheric warming itself contributes most strongly to the CAPE increase, but the indirect effect of increases in the water vapor scale height with warming also contribute to increasing CAPE beyond that expected from Clausius‐Clapeyron. Plain Language Summary: Idealized model simulations of the tropical atmosphere disagree on profiles of temperature and humidity. Here we use simple theory to understand the intermodel spread in humidity and in a measure of instability to convection (small‐scale rising motion). There is greater instability in models that are on average moister. We find that model‐to‐model variations in small‐scale turbulent mixing between cloudy and clear air cause the intermodel spread in instability. Model‐to‐model variations in the fraction of cloud water that reaches the surface as rainfall cause the intermodel spread in humidity. The instability increases substantially with warming, which is driven by a warmer and moister lower atmosphere. Key Points: A stability‐relative humidity phase space is used to diagnose theory‐implied entrainment and precipitation efficiency in RCEVariations in entrainment explain intermodel spread in CAPE but variations in precipitation efficiency explain spread in humidityIncreases in the water vapor scale height with warming lead to CAPE increases with warming that are faster than Clausius‐Clapeyron scaling [ABSTRACT FROM AUTHOR]

Relative humidity (RH) is projected to increase over ocean but decrease over land under anthropogenic warming. The land RH decrease was previously attributed to ocean influences on land changes. Here, we show that interactive soil moisture (SM) is necessary and may be sufficient for anthropogenic warming to reduce the land RH. The land RH decrease is absent in simulations with realistic land‐ocean geometry but fixed SM, and present in simulations with interactive SM but no oceans or changes in precipitation minus evaporation. The land RH decrease is coupled to the SM decline and the latter could be understood as a natural response of interactive SM to anthropogenic warming. Specifically, prior to adjustments in SM and RH, evaporation would increase by ∼6% K−1 following the Clausius–Clapeyron relation, outpacing the radiatively constrained ∼2% K−1 precipitation increase. This prior imbalance depletes SM and consequently reduces RH through the coupling between SM and RH. Plain Language Summary: As a measure of air wetness, relative humidity (RH) is projected to decrease over land under anthropogenic warming, contributing to increasing evaporative demand and intensifying droughts, heatwaves and wildfires. The land RH decrease was previously attributed to influences from ocean, but here we propose an alternative explanation. We first show that the land RH decrease is coupled with the soil moisture (SM) decline. Then, by excluding interactive SM and ocean influences respectively in warming simulations, we illustrate that interactive soil moisture (i.e., soil moisture is fed by precipitation minus evaporation and can in turn affect evaporation through moisture availability) is necessary and may be sufficient to produce a drier land under anthropogenic warming. A conceptual understanding of this declined SM and RH is provided based on theoretical evaporation equations. Key Points: We propose a new explanation for the projected decrease in land relative humidity under anthropogenic warmingComplex and idealized simulations show that interactive soil moisture (SM) is necessary and sufficient for anthropogenic warming to dry the landInteractive SM allows prior imbalance in evaporation and precipitation increases to dry the land independent of ocean influence [ABSTRACT FROM AUTHOR]

Although deterioration of soil due to freeze–thaw cycles has been investigated based on element tests and small-scale laboratory model tests, there still lacks fundamental understanding of slope response under cyclic freeze–thaw action. In this study, a novel in-flight freeze–thaw system was developed to investigate the thermal, hydraulic and mechanical response of a typical unsaturated slope under seven freeze–thaw cycles in the centrifuge. Temperature, suction and deformation were measured during the test. The test results show that the suction at the freezing front can be up to about 1 MPa. The comparison between measured and theoretically predicted suction elucidates that using the temperature-dependent Clausius–Clapeyron equation is inadequate to model suction evolution precisely when considering water migration. The subsequent thawing reduces the suction to 9 kPa, which is about 60% lower than during the initial unfrozen state. The suction destruction softens the surface soil layer, leading to downslope movement during thawing. During the seasonal downward ratcheting movement, the lower elevation of the slope can flatten from 59° to 50°. The repeated freeze–thaw action generates significant fractures at the soil surface while deep cracks can form due to tensile rupture. Freeze–thaw-induced seasonal variation of suction softens the post-thawed slope, leading to accumulated plastic deformation and shallow slope failure. [ABSTRACT FROM AUTHOR]

Distillation is a typical unit operation for separating liquid mixtures. The temperature-composition curve in the gas-liquid equilibrium phase diagram is important for guiding distillation operations. An ideal liquid mixture with two components was utilized as the study system in this work. We proved that the temperature-composition curve (T- x or T-y) of ideal liquid mixtures with two components is strictly monotonic, regardless of whether the saturated vapor pressure of liquid conforms to the Clausius-Clapeyron equation or Antoine equation. This means that the bubble point temperature and dew point temperature increase monotonously with the increase of lowly volatile substance content. [ABSTRACT FROM AUTHOR]

This paper investigates the phase equilibrium conditions in the carbon dioxide hydrate forming system. Carbon dioxide hydrate can be utilized for carbon capture, salt manufacture, carbonated solid foods and tritium water concentration, so the phase equilibrium conditions have been substantially reported so far. However, the data from previous studies were inconsistent with each other, such as there is a difference of 1.0 K in the phase equilibrium temperature at 2 MPa. In this study, the newly three-phase (water rich liquid + hydrate + guest rich vapor) equilibrium conditions in the carbon dioxide hydrate forming system were measured at twenty different temperature conditions within the range of (271.9-282.7) K in the two different laboratories. The six pairs of the three-phase equilibrium condition data measured under equivalent pressure conditions were consistent within mutual uncertainties. The internal consistency of the data measured in this study was evaluated by the Clausius-Clapeyron equation. The data measured in this study existed within the uncertainty range of the data from several previous studies. [ABSTRACT FROM AUTHOR]

A system of mutually consistent equations describing the pressure , vapor density , and liquid density on the phase equilibrium line of technically important substances in the range from the triple to critical points has been proposed. At the stage of development of this system, the following have been considered: (a) the features of the behavior of a number of properties ( , , , is the average diameter of the saturation line, and is the order parameter) in the critical region; (b) some concepts of the scale theory of critical phenomena and renormalization group theory, which was adapted by Wang L. et al. (2013) for substances with a given molecular structure, including SF6; (c) the Clausius–Clapeyron equation, in which the "apparent" vaporization heat is used instead of the vaporization heat . At the stage of approbation of this system of equations, a method for calculating the adjustable coefficients included in this system using the example of SF6, for which precision data on the thermal properties including the experimental ( , , , ) data are available, has been proposed. Using the proposed technique, the coefficients of the system of equations have been determined using the precision data for SF6 and the calculated values of the SF6 properties in a given temperature range have been obtained. The uncertainty of the calculated data has been statistically analyzed; in particular, the average squared deviations of the experimental ( , , , ) data from the corresponding equations have been found. It has been shown that the proposed system describes the listed properties with less uncertainty than that of the properties corresponding to the original equations of Funke et al. (2001). The temperature dependence of the proposed model satisfactorily agrees with the model developed by Wang et al. (2013) for the SF6 critical region. [ABSTRACT FROM AUTHOR]

P−T and V−T phase diagrams of cyclic hydrocarbons, namely benzene (C6H6), cyclopentane (C5H10), thiophene (C4H4S), and tetrahydrofuran (C4H8O), were constructed using both literature and our experimental data obtained during the study of isochoric thermal conductivity in high-temperature phase. The V−T phase diagrams of cyclohexane (C6H12) and furan (C4H4O), presented earlier, were refined and supplemented with P−T diagrams. The possibility of constructing a phase diagram for cyclohexene (C6H10) is also discussed. The changes in molar volume during melting and the boundaries of the existence of high-temperature phases have been determined. The magnitudes of thermal pressure of cyclic hydrocarbons studied were obtained. Experimental values of dPm/dT on melting line were compared with those calculated by the Clapeyron-Clausius equation. [ABSTRACT FROM AUTHOR]

Flow‐dependent errors in tropical analyses and short‐range forecasts are analysed using global observing‐system simulation experiments assimilating only temperature, only winds, and both data types using the ensemble Kalman filter (EnKF) Data Assimilation Research Testbed (DART) and a perfect model framework. The idealised, homogeneous observation network provides profiles of wind and temperature data from the nature run for January 2018 using the National Center for Atmospheric Research (NCAR) Community Earth System Model (CESM) forced by the observed sea‐surface temperature. The results show that the assimilation of abundant wind observations in a perfect model makes the temperature data in the Tropics largely uninformative. Furthermore, the assimilation of wind data reduces the background errors in specific humidity twice as much as the assimilation of temperature observations. In all experiments, the largest analysis uncertainties and the largest short‐term forecast errors are found in regions of strong vertical and longitudinal gradients in the background wind, especially in the upper troposphere and lower stratosphere over the Indian Ocean and Maritime Continent. The horizontal error correlation scales are on average short throughout the troposphere, just several hundred km. The correlation scales of the wind variables in precipitating regions are half of those in nonprecipitating regions. In precipitating regions, the correlations are elongated vertically, especially for the wind variables. Strong positive cross‐correlations between temperature and specific humidity in the precipitating regions are explained using the Clausius–Clapeyron equation. [ABSTRACT FROM AUTHOR]

Downscaling methods are critical in efficiently generating high‐resolution atmospheric data. However, state‐of‐the‐art statistical or dynamical downscaling techniques either suffer from the high computational cost of running a physical model or require high‐resolution data to develop a downscaling tool. Here, we demonstrate a recently proposed zero‐shot super‐resolution method, the Fourier neural operator (FNO), to efficiently perform downscaling without the need for high‐resolution data. Because the FNO learns dynamics in Fourier space, FNO is a resolution‐invariant emulator; it can be trained at a coarse resolution and produces emulation at any high resolution. We applied FNO to downscale a 4‐km resolution Weather Research and Forecasting (WRF) Model simulation of near‐surface heat‐related variables over the Great Lakes region. The FNO is driven by the atmospheric forcings and topographic features used in the WRF model at the same resolution. We incorporated a physics‐constrained loss in FNO by using the Clausius–Clapeyron relation to better constrain the relations among the emulated states. Trained on merely 600 WRF snapshots at 4‐km resolution, the FNO shows comparable performance with a widely‐used convolutional network, U‐Net, achieving averaged modified Kling–Gupta Efficiency of 0.88 and 0.94 on the test data set for temperature and pressure, respectively. We then employed the FNO to produce 1‐km emulations to reproduce the fine climate features. Further, by taking the WRF simulation as ground truth, we show consistent performances at the two resolutions, suggesting the reliability of FNO in producing high‐resolution dynamics. Our study demonstrates the potential of using FNO for zero‐shot super‐resolution in generating first‐order estimation on atmospheric modeling. Plain Language Summary: High‐resolution climate estimates are crucial for applications like examining heat exposure in populated areas. Downscaling from lower‐resolution estimates is one popular technique for obtaining these estimates. However, developing downscaling tools usually requires expensive computation or difficult‐to‐obtain data; they rely on either numerically solving a physical model or using a pair of existing high‐ and low‐resolution data. To address this issue, we demonstrated a novel deep learning model that can generate high‐resolution results from only low‐resolution data. Our study successfully applied this method to downscale near‐surface heat‐related variables of the Weather Research and Forecasting simulation to 1‐km resolution over the Great Lakes region. Key Points: We used the Fourier neural operator (FNO) to perform zero‐shot super‐resolution on near‐surface heat‐related estimatesIncorporating a physics‐constrained loss based on the Clausius–Clapeyron equation improves the emulation performance of the trained FNOTrained on a 4‐km Weather Research and Forecasting simulation, the FNO generates a 1‐km emulation that captures fine‐grained climate features induced by topography [ABSTRACT FROM AUTHOR]

Electrically and thermally induced transitions between ferroelectric and relaxor states are of great importance for Bi1/2Na1/2TiO3 (BNT)-based materials because of their close relevance to electromechanical properties. In this study, the electric field-temperature (E-T) phase diagrams of Fe doped Bi1/2(Na0.8K0.2)1/2TiO3 (BNKT) ceramics are constructed via an experiment and theory combined approach. A novel phenomenological model based on the Landau-Devonshire theory and the Preisach model is proposed to describe the electric field induced phase transitions. Using this model, an approximate free-energy landscape is obtained by fitting the experimental double polarization-electric field loop, and then the electric field representing ferroelectric and relaxor two-phase equilibrium is calculated from the free-energy landscape for the construction of an E-T phase diagram. The constructed E-T phase diagrams meet basic thermodynamics requirements, for example, the Clausius-Clapeyron relation, and, therefore, overcome some of the shortcomings of previously reported E-T phase diagrams for BNT-based ceramics. The relationship between the E-T phase diagram and electromechanical properties is also established. From the E-T phase diagrams, it is predicted that Fe doping could lower the threshold field of triggering giant strains of BNKT ceramics at a high temperature. This prediction is successfully verified by experimental measurement of the electric field induced strain. At the optimized temperature for strain property, the threshold field of triggering giant strain is estimated to be about 2.6 kV/mm for a 3.0% Fe doped sample, significantly lower than 3.5 kV/mm for the undoped sample. This shows that the E-T phase diagram can provide valuable guidance for the improvement of electromechanical properties of BNT-based ceramics. [ABSTRACT FROM AUTHOR]

In the binary Fe-rich Fe-Ni system, martensite start temperatures MS decrease from 500 to 200 K when Ni concentrations increase from 20 to 30 at.%. It is well known that alloys with Ni concentrations below 28.5 at.% exhibit lath martensite (LM) microstructures (athermal transformation, small crystals, accommodation by dislocations). Above this concentration, plate martensite (PM) forms (burst-like transformation, large crystals, accommodation by twins). The present work is based on a combination of (i) ingot metallurgy for the manufacturing of Fe-Ni alloys with varying Ni-concentrations, (ii) thermal analysis to measure phase transformation temperatures with a special focus on MS, and (iii) analytical orientation imaging scanning electron microscopy for a quantitative description of microstructures and crystallographic features. For Ni-concentrations close to 28.5 at.%, the descending MS-curve shows a local maximum, which has been overlooked in prior works. Beyond the local maximum, MS temperatures decrease again and follow the overall trend. The local maximum is associated with the formation of transition martensite (TM) microstructure, which exhibits LM and PM features. TM forms at higher MS temperatures, as it is accommodated by simultaneous twinning and dislocation slip. An adopted version of the Clausius-Clapeyron equation explains the correlation between simultaneous accommodation and increased transformation temperatures. [ABSTRACT FROM AUTHOR]

N2 and O2 adsorption isotherms in chemically modified clinoptilolite-Ca zeolites were experimentally estimated by inverse adsorption chromatography. Natural zeolites (CLINA) were chemically treated with HCl at different concentrations (H1-H4). The adsorption of N2 and O2 on these zeolites was studied in the temperature zone of 398–498 K using gas chromatography. This technique used a thermal-conductivity detector and He as carrier gas, at a rate of 30 mL min−1. The Langmuir and Henry equations were used to describe the experimental results of these gases' adsorption. To evaluate the selectivity of the components of atmospheric air, the chemical activation of the zeolite clinoptilolite-Ca has been carried out. The results are attractive because of the ability to separate the gases these nanomaterials present under dynamic conditions. The structural modifications of the crystalline phases of the studied zeolites were carried out through X-ray diffraction, where the average crystal size was evaluated with the Scherrer equation, finding values of 25.86 nm for CLINA and 15.12 nm for H3 zeolites. The variation of their chemical composition was carried out by energy-dispersive EDS, while the adsorption of N2 carried out their texture properties at 77 K. The selectivity coefficients (α) were evaluated for these gases in pure form and in a mixture (atmospheric air), finding the highest values in zeolites H4 and H3. The interaction energies between these gases with the porous structures of the studied zeolites were evaluated from the evolution of the isosteric enthalpies of adsorption through the Clausius–Clapeyron equation. [ABSTRACT FROM AUTHOR]

The phase change energetics of adamantane, 1-adamantanemethanol, 1-adamantanethanol, 1-adamantanecarboxylic acid, and 1-adamantaneacetic acid is reported. To conduct the study of the compounds' phase changes, calorimetric techniques and theoretical methodologies were applied. Mole fraction purities, enthalpies, fusion temperatures, and solid phase heat capacities were obtained using differential scanning calorimetry. Enthalpies of sublimation were determined from measurements of mass loss rate and the Clausius-Clapeyron and Langmuir equations, i.e., through thermogravimetric analysis. The gas-phase heat capacities of all stable conformers of the adamantane derivatives at different temperatures were estimated using harmonic oscillator approximation. Finally, the molecular interactions of the adamantane derivatives are discussed. [ABSTRACT FROM AUTHOR]

HFOs are currently being adopted for adsorption refrigeration applications due to their zero ozone depletion potential and paltry global warming potential. In this study, a constant volume variable pressure (CVVP) system is designed and built to experimentally investigate the adsorption characteristics of HFO-1234ze(E) onto Maxsorb III. Experiments were performed to obtain refrigerant uptakes at adsorption temperatures of 30, 40, and 50°C at variable refrigerant pressures. The maximum experimental adsorption uptake is 1.73 kg·kg–1 at 0.607 relative pressure. The uptake starts to increase sharply from 0.01 relative pressure and slows down at 0.2 relative pressure. The experimental adsorption isotherm data were correlated with Tóth and Dubinin-Astakhov (D–A) adsorption isotherm models. Uptake difference based on Tóth and D–A adsorption model at possible working temperature has been simulated. Isosteric heats of adsorption were determined from Clausius–Clapeyron relation, and their dependence on uptake was also analyzed and reported. Additionally, the specific cooling effects and coefficient of performance are investigated. These findings are crucial for the system performance assessment of a practical adsorption refrigeration system. [ABSTRACT FROM AUTHOR]

Under global warming, the climate in semi-arid inland Eurasia (SAIE) has changed in an opposite manner, thereby seriously impacting the local ecological environment. However, the key influencing factors and physical mechanism remain inconclusive. In this paper, we remodel the precipitation recycling ratio (PRR) model to assess the contributions of moisture from different water vapor sources to local precipitation, analyze the characteristics of the PRR and precipitation in SAIE, and provide possible physical reasons based on the Clausius–Clapeyron equation. It is found that the PRR increased from 1970 to 2017 as the result of linear trend analysis, with obvious seasonality. Moreover, the component of precipitation contributed by locally evaporated moisture (Pl), and that contributed by advected moisture (Pa) as well as the total precipitation (P), increased during the past 48 years. In particular, the Pa, Pl, and P in autumn and winter all increased obviously during the past 20 years from the interdecadal change trend, as well as the PRR (Pl/P), which was opposite to the decrease in the total water vapor input I(Ω) in the horizontal direction. According to the Clausius–Clapeyron equation, one of the causes might be that global warming has accelerated the local water cycle and driven the increase in Pa, and the increase in atmospheric water holding capacity caused by global warming provides the power source. We suggest that the climate's transformation from dry to wet in SAIE can only be temporary since SAIE is an inland area and the adjustment of atmospheric circulation did not lead to the increase in external water vapor. [ABSTRACT FROM AUTHOR]

The present study summarizes various findings such as equilibrium moisture contents, effect of temperature and relative humidity, better fitted model for wood sorption, heat transfer characteristic and influence of the wood structure. For this purpose, three African tropical medium-heavy woods were used: Sapelli (Entandrophragma cylindricum (Sprague) Sprague), Sipo (Entandrophragma utile (Dawe & Sprague) Sprague), Kosipo (Entandrophragma candollei Harms). Adsorption and desorption isotherms were measured using the static gravimetric method at 30, 40, 50, 60 °C within the range of 5.5 – 83.6% relative humidity. Thermodynamic properties were calculated from the Clausius-Clapeyron and Avramidis equations. Quantitative anatomical parameters of the woods were determined from the SEM images. Results showed that the highest mean values of the measured anatomical parameters were obtained with Sipo and the lowest with Sapelli. The equilibrium moisture content obtained is relatively lower for Kosipo and higher for Sipo at low temperatures (T < 50 °C) and Sapelli at high temperatures (T ≥ 50 °C). The highest values of thermodynamic properties were obtained with Kosipo and the lowest with Sipo. Results of sorption characteristics are correlated with the anatomical structure of the woods studied. Sipo, with lower density (0.64) and higher vessel diameter, vessel proportion and ray size, has higher moisture content and lower thermodynamic properties. However, this trend is not respected between Kosipo and Sapelli. Kosipo, with a higher density and anatomical parameters, has lower moisture content and higher thermodynamic properties than Sapelli. This could be explained by a lower content of amorphous polymers and the presence of silica in some anatomical elements of Kosipo. [ABSTRACT FROM AUTHOR]

Core–shell-like structured polymeric ionic liquid hybrid nanoreactors with "internal hydrophobic–external hydrophilic" characteristics were successfully synthesized through the Stöber method and reversible addition–fragmentation chain transfer (RAFT) polymerization. Firstly, we introduced hydrophobic organosilicon as an inner core and fixed Pd nanoparticles (∼0.69 mmol g−1) in the pore and finally constructed a hydrophilic shell, which not only ensured the dispersity of the catalyst in water but also effectively prevented the leaching of Pd species. The structure and properties of nMIE@Pd/SiNP-CPDB were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), N2 adsorption–desorption, ICP-OES, thermogravimetric analysis (TGA) and ultraviolet and visible spectrophotometry (UV-vis) characterization methods. The adsorption enthalpy of the best catalyst for styrene was calculated using the Clausius–Clapeyron equation and the value was −12.765 kJ mol−1, which strongly verified that the prepared catalyst could effectively promote mass transfer and the adsorption of reactants or products. Furthermore, the as-prepared nanoreactors exhibit distinguished catalytic activity for aqueous hydrogenation reactions and even after 7 cycles, the catalysts still maintain their superior catalytic activity, showing almost no leaching of palladium species. [ABSTRACT FROM AUTHOR]

Energy balance models (EBMs) have been widely used in a range of climate problems, but the assumption of constant diffusivity in the parameterization of the moist static energy (MSE) flux can hardly be justified. We demonstrate in this study that the diffusive MSE flux can be derived from the basic energy balance equation with a few tolerable assumptions. The estimated diffusivity is both spatially and seasonally dependent, and its midlatitude average is then tested against several scaling theories for the midlatitude eddy diffusivity. The result supports the diffusivity theory of Held and Larichev modified for the moist atmosphere, affording a dynamics-based parameterization of MSE diffusivity. The implementation of the parameterization in an EBM leads to an interactive MSE diffusivity that accounts for the midlatitude eddy response to climate forcing perturbations. Under a uniform radiative forcing, the EBM with a diffusivity so parameterized produces a weakening of the midlatitude diffusivity and a modestly polar-amplified surface temperature response as an inevitable outcome under the dual constraints of the nonlinear Clausius–Clapeyron relation and the temperature gradient-dependent diffusivity, even in the absence of any poleward-amplifying radiative feedbacks. As the consequence of more isothermal temperature and reduced diffusivity, the variance of the midlatitude surface temperature also decreases with warming. [ABSTRACT FROM AUTHOR]

A temperature-dependent water retention curve (WRC) model is necessary in numerous geotechnical engineering cases such as the disposal and storage of nuclear waste, buried high-voltage cables, heat dissipation embankments and geothermal structures. A series of pioneering models attempting to consider the mechanisms of temperature effect have been proposed. Nevertheless, it should be noted that very limited research can be found in the literature to consider temperature effects on both capillarity and adsorption. Thus, a temperature-dependent WRC model for both adsorption and capillarity is developed in this study. An adsorption equation is first proposed by integrating Kelvin equation, Clausius–Clapeyron equation and the adsorption enthalpy equation. Then, the proposed adsorption equation and an existing capillary equation are incorporated into Peters–Durner–Iden (PDI) model to establish the temperature-dependent WRC model. Sixteen series of non-isothermal WRC data are employed to illustrate the application and performances of the proposed model. The proposed WRC model provides good agreement between the predicted and measured temperature-dependent WRCs. Moreover, the main differences between different types of soils are temperature effects on adsorption. The value of parameter α gradually increases from sandy soils to bentonite, representing an increasingly strong soil–water interaction and increasingly significant temperature effects on adsorption. By comparing with three existing models, the proposed model is found as the most suitable for describing the observed data. [ABSTRACT FROM AUTHOR]

This paper determines the thermodynamic phase diagram of the EXP system of particles interacting by the purely repulsive exponential pair potential. The solid phase is face-centered cubic (fcc) at low densities and pressures. At higher densities and pressures, the solid phase is body-centered cubic (bcc) with a re-entrant liquid phase at the highest pressures simulated. The investigation first identifies the phase diagram at zero temperature at which the following four crystal structures are considered: fcc, bcc, hexagonal close packed, and cubic diamond. There is a T = 0 phase transition at pressure 2.651 × 10−3 with the thermodynamically stable structure being fcc below and bcc above this pressure. The densities of the two crystal structures at the phase transition are 1.7469 × 10−2 (fcc) and 1.7471 × 10−2 (bcc). At finite temperatures, the fcc–bcc, fcc-liquid, and bcc-liquid coexistence lines are determined by numerical integration of the Clausius–Clapeyron equation and validated by interface-pinning simulations at selected state points. The bcc-fcc phase transition is a weak first-order transition. The liquid-fcc–bcc triple point, which is determined by the interface-pinning method, has temperature 5.9 × 10−5 and pressure 2.5 × 10−6; the triple-point densities are 1.556 × 10−3 (liquid), 1.583 × 10−3 (bcc), and 1.587 × 10−3 (fcc). [ABSTRACT FROM AUTHOR]

Dry ground meat is a cooked meat product. It is a popular meat product in Central Anatolian Region of Turkey. Calf plate or flank meats and intermuscular fats are used in the production of dry ground meat. In this study, sorption isotherms were determined using nine different salt solutions (0.1-0.9 aw) having different relative humidity values at 5, 15 and 25°C. From the experimental data obtained, it was found that the sorption isotherms had Type-II characteristics. The obtained experimental data were applied to Iglesias-Chirife, Oswin, BET, Harkins-Jura, Smith, Henderson, Halsey, GAB, Peleg. Iglesias-Chirife and Peleg equations were revealed the best fitting. Isosteric heats of adsorption were evaluated by applying the Clausius-Clapeyron equation to experimental isotherms and decreased with increasing moisture content. [ABSTRACT FROM AUTHOR]

Summary: Pressure swing adsorption (PSA) technology is widely applied to hydrogen purification from mixed gas. This article mainly studies the adsorption dynamics, breakthrough behavior, and temperature profiles of the typical H2/CO2 mixture by activated carbon in the adsorption bed. Based on the Comsol Multiphysics simulation platform, a one‐dimensional multicomponent adsorption, heat and mass transfer modeling is established and validated by published data of H2/CO2 adsorption breakthrough experiments. By comparing the simulated data with the experimental data, it is found that the breakthrough curves are in good agreement, but the temperature profiles are not fit perfectly. After a comprehensive literature review, we found that the heat of adsorption dramatically influences the temperature profiles. The constant heat of adsorption has limitations for modeling breakthrough experiments. A variable heat of adsorption was proposed and applied to improve the temperature profiles. The results show that the variable heat of adsorption can effectively improve the temperature profiles in the gas adsorption process, and it works well for different adsorption temperatures, pressures, and compositions. The variable heat of adsorption instead of the constant heat of adsorption can significantly increase the peak value of the temperature profiles to be more consistent with experimental results. The relative deviations between the simulated and experimental values of the temperature profiles are reduced from 11.42% to 1.47% using the variable heat of adsorption. The simplification form of the Clausius‐Clapeyron equation gives the outline and trend of the correlation between the heat of adsorption and the amount of adsorption for different adsorption temperatures, pressures, and compositions. [ABSTRACT FROM AUTHOR]

The impacts of global warming on Meiyu–Baiu extreme rainfall and the associated mid-latitude synoptic-scale weather systems over the Eastern China (EC) and the Baiu rainband (Bu) regions in East Asia have been examined, based on simulations from the 20-km Meteorological Research Institute atmospheric general circulation model (MRI-AGCM3.2S). This model was demonstrated to give realistic Asian extreme rainfall, when compared with data from the Tropical Rainfall Measuring Mission (TRMM). Here we used a novel wave-selection algorithm based on the 300 hPa wind, in order to identify upper-level propagating wave signals in conjunction with the occurrence of extreme precipitation in either EC or Bu. The same algorithm was applied for both the present (1979–2003) and future (2075–2099) climate simulations from the AGCM, so as to infer the impacts of global warming on the behavior of these systems. Results show robust decrease of intensity of systems influencing both Bu and EC in the future warmer climate. Their corresponding low-to-mid level circulation, as revealed by vertical velocity, temperature advection and sea-level pressure composites, was also found to be weakened. This is likely related to changes in the background circulation in future over the East Asian mid-latitude zone, such as the widespread increment of the seasonal mean static stability at 500 hPa. However, the wave-associated precipitation over these regions was enhanced in the future climate simulations. This can be attributed to more strong intensity rainfall, which increases as the background temperature in these regions warms, largely following the Clausius–Clapeyron relation. Therefore, changes of wave-related extreme precipitation in EC and Bu are mainly controlled by the thermodynamic effect; the latter appears to be much stronger than the potential impacts due to the slight weakening of these weather systems. [ABSTRACT FROM AUTHOR]

Four ionic liquids (ILs) based on the bis(trifluoromethanesulfonyl)imide (NTf2) anion were synthesized and characterized concerning their thermal stability, the occurrence of low temperature phase transitions and their volatility. All these physical quantities are highly important for possible applications. Both monocationic and dicationic ILs were considered. All ILs exhibit thermal stability exceeding 350 °C, an extremely high value, due to the presence of the NTf2 anion. Monocationic ILs can undergo crystallization, and they melt at 1 and 38 °C. On the contrary, dicationic ILs containing large positively charged ions display only a glass transition around −40 °C, without any crystallization or melting process; this fact is particularly important in view of the possibly low temperature applications of the dication ILs. The vapor pressure, pv, of the four ILs was measured by isothermal thermogravimetry in the temperature range between 250 and 325 °C; the lowest values of pv were obtained for the two dicationic liquids, suggesting that they are particularly well suited for high temperature applications. The vaporization enthalpy was calculated through the Clausius–Clapeyron equation and was found in the range between ~140 and ~180 kJ/mol depending on the specific IL. [ABSTRACT FROM AUTHOR]

We propose a new concept of heat-storage material that utilizes thermoelastic martensitic transformation in a TiNi-based alloy. In the material, the stored thermal energy is maintained over a wide temperature range between the thermal absorption and desorption temperatures, and the stored energy is released on demand by external stress on the ground of a latent heat of the stress-induced martensitic transformation. The heat-storage temperature range was effectively increased through a thermomechanical treatment without changing the amount of latent heat. The tensile force applied to the treated sample released to the environment more heat than the unbiased desorption temperature. The amount of heat released was in agreement with the values expected from the Clausius–Clapeyron equation and differential scanning calorimetry profiles. The amount of heat released was confirmed to remain unchanged up to the 9th cycle when the release process was repeated at 286 K by applying tension after heat absorption. [Display omitted] [ABSTRACT FROM AUTHOR]

The primary aim of this research is to comprehensively assess the applicability of chitosan biopolymer towards water treatment application and to enhance its adsorption capacity towards Remazol brilliant blue R-19 dye. This has been achieved through physical modification to obtain the material in hydrogel form and chemical modification by crosslinking it with barbituric acid. The characterization of the resulting Chitosan-barbituric acid hydrogel (CBH) was carried out using various analytical techniques such as SEM-EDX, FT-IR, TGA-DTA, XRD, and BET. CBH was employed as the adsorbent to eliminate R-19 dye from aqueous media. Utilizing response surface methodology (RSM), the parameters were fine-tuned, leading to the achievement of more than a 95% removal for R-19 dye. The adsorption behavior closely adhered to the Langmuir isotherm and pseudo-second-order kinetics. An interesting observation indicated that the rise in temperature leads to rise in adsorption capacity of CBH. The maximum adsorption capacities evaluated at 301.15 K, 313.15 K, 318.15 K, and 323.15 K were 566.6 mg g−1, 624.7 mg g−1, 671.3 mg g−1, and 713.5 mg g−1 respectively, in accordance with the Langmuir isotherm model. Examining the thermodynamics of the adsorption process revealed its spontaneous nature (ΔG = −21.14 to −27.09 kJ mol−1) across the entire temperature range. Furthermore, the assessment of the isosteric heat of adsorption (ΔH ads) was conducted using the Clausius–Clapeyron equation, with results indicating an increase in ΔH ads from 1.85 to 2.16 kJ mol−1 with temperature rise from 301.15 K to 323.15 K due to augmented surface loading. This suggested the existence of lateral interactions between the adsorbed dye molecules. The potential of adsorbent for regeneration was investigated, demonstrating the ability to reuse the material. Sustainability parameter calculated for synthesis process reflected a notably low E-factor value of 0.32 demonstrated the synthesis is environment friendly. [Display omitted] • Chitosan was crosslinked using barbituric acid to get hydrogel. • It was characterized and subjected to R-19 dye amputation. • The q m value was increased to 713.5 mg g−1at 323.15 K under optimum conditions. • RSM was used to optimize the pH, dose, time and concentration against temperature. • Studies of regeneration demonstrated that the adsorbent CBH is economically viable. [ABSTRACT FROM AUTHOR]

Experimental adsorption and desorption behavior of Matricaria pubescens was determined using the gravimetric static method at 30°C, 40°C and 50°C, for water activity ranging from 0.057 to 0.898. Experimental data were compared with eight widely recommended sorption models (Caurie, BET, Henderson-Thomson, Smith, Halsey, Oswin, Peleg, and Adam and Shove) in literature. Peleg and Halsey models were found to be the most suitable for describing sorption isotherm curves. The net isosteric heats of sorption were also calculated by using the Clausius-Clapeyron equation. [ABSTRACT FROM AUTHOR]

Prediction of adsorption isotherms under different temperatures is significant to reserve estimation of shale gas reservoirs. Based on the Polanyi adsorption potential theory and Langmuir adsorption theory, a method was presented to predict adsorption isotherms at different temperatures. In this method, the relationship between Langmuir pressure and temperature was quantified. By utilizing this method, we predicted adsorption isotherms of Longmaxi shale from 45 °C to 120 °C according to experimental data at 30 °C. Meanwhile, by considering the pressure and temperature gradients, we also predicted the adsorption capacity of Longmaxi shale with geologic depth. Results show that the adsorption data predicted by our method are in accord with experimental data and the error coefficient is less than 5%. In addition, the isosteric heat of adsorption for Longmaxi shale can be calculated by predicted adsorption data based on the Clausius–Clapeyron equation of capillary systems. Therefore, our study illustrates theoretical foundations for the efficient evaluation of adsorbed gas content in shale gas reservoirs at geologic conditions. [ABSTRACT FROM AUTHOR]

In the designed (1- x)Mn 3 GaN- x Mn 3 SbN (0.2 ≤ x ≤ 0.8) heterogeneous system, modulating the non-collinear antiferromagnetic (AFM) phase transitions of antiperovskite Mn 3 GaN using thermal stress is realized for the first time. With growing the Mn 3 SbN secondary phase, the Neel temperature (T N) of Mn 3 GaN phase shifts down by 40 K and then disappears, but another magnetic transition below T N appears and shifts up by 125 K. The neutron powder diffraction (NPD) results of the sample with x = 0.6 show that the magnetic transition below T N ascribed to the decreasing Mn–Mn distance (d Mn–Mn) and spin re-orientation from Γ5g to a new non-collinear M 2 AFM phase. By the NPD analysis, the d Mn–Mn of the Mn 3 GaN phase decreases from 2.75527(4) Å to 2.73925(3) Å, and the angles of the spin rotations for Mn1/Mn2, Mn3-1, and Mn3-2 atoms in M 2 AFM during the spin re-orientation process are 90°, 60°, and 60°, respectively. Negative thermal expansion behaviors and caloric effects associated with Γ5g phase transitions are investigated systematically. Further, the thermal stress could be regulated by adjusting the proportion of Mn 3 GaN and Mn 3 SbN phases with mismatched thermal expansion, which could be estimated even up to GPa according to Clausius–Clapeyron relation. [ABSTRACT FROM AUTHOR]

Powders based on plant raw materials have low storage stability due to their sorption and thermal properties and generate problems during processing. Therefore, there is a need to find carrier agents to improve their storage life as well as methods to evaluate their properties during storage. Water adsorption isotherms and thermal characteristics of the pumpkin powder with various inulin additions were investigated in order to develop state diagrams. Differential scanning calorimetry (DSC) was used to obtained glass transition lines, freezing curves and maximal-freeze-concentration conditions. The glass transition lines were developed using the Gordon–Taylor model. Freezing data were modeled employing the Clausius–Clapeyron equation and its development–Chen model. The glass transition temperature of anhydrous material (Tgs) and characteristic glass transition temperature of maximum-freeze-concentration (Tg′) increased with growing inulin additions. Sorption isotherms of the powders were determined at 25 °C by the static-gravimetric method and the experimental data was modeled with four different mathematical models. The Peleg model was the most adequate to describe the sorption data of the pumpkin–inulin powders. Guggenheim-Anderson-de Boer (GAB) monolayer capacity decreased with increasing inulin concentration in the sample. [ABSTRACT FROM AUTHOR]

This study focuses on the investigation of the predictive capability of the Clausius–Clapeyron (C–C) equation in conjunction with soil–water retention characteristics to estimate soil-freezing curves (SFC). The Clausius–Clapeyron equation together with soil–water retention (SWR) models can provide a quick estimation of SFCs. However, the validity of the equilibrium assumption may not be applicable in all scenarios of freezing and thawing. The overall goal of this study is to provide a comprehensive assessment of SWRC-derived soil-freezing curves for different types of soils under varying environmental conditions. An extensive set of data obtained from studies reported in the literature pertaining to thermally induced hydraulic properties of sand, silt, and clay soils from multiscale experiments was analyzed. In addition, in-house laboratory freeze–thaw experiments were performed using silty soil. The SFCs derived from the SWRC were in good agreement with the measured SFCs for sands, whereas significant discrepancies were noted for silt and clay soils. Intensified discrepancies were noted when the results from different experimental methods and changing boundary conditions were compared. A significant hydraulic hysteresis was observed and possible controlling mechanisms were explained. A reliable method to predict SFC from SWRC will enable accurate modeling of coupled heat transfer and water flow processes in the Arctic subsurface for sustainable built and natural environments. [ABSTRACT FROM AUTHOR]

We analyzed a large ensemble dataset called the database for Policy Decision Making for Future climate change (d4PDF), which contains 60-km resolution atmospheric general circulation model output and 20-km resolution dynamical downscaling for the Japanese domain. The increase in moisture and precipitation, and their global warming response in June–July–August were described focusing on the differences between Hokkaido and Kyushu; Hokkaido is cool and dry and Kyushu is hot and humid in the current climate. The results suggested that the specific humidity increased almost following the Clausius Clapeyron relation, but the change in stationary circulation suppressed the precipitation increase, except for in western Kyushu. The + 4 K climate in Hokkaido would be as hot and humid as the present climate in Kyushu. The circulation change related to the southward shift of the jet stream and an eastward shift of the Bonin high weakened the moisture flux convergence via a stationary field over central Japan including eastern Kyushu. The transient eddy activity counteracted the increase in humidity, so that the moisture flux convergence and precipitation did not change much over Hokkaido. Because the contribution of tropical cyclones to the total precipitation was at most 10%, the decrease in the number of tropical cyclones did not explain the predicted change in precipitation. [ABSTRACT FROM AUTHOR]

Extreme events happen frequently in the context of global warming, particularly in the arid and semi-arid regions, such as Xinjiang. The global surface temperature has increased to allow more water vapor entering the atmosphere, which intensifying the global water cycle. Meanwhile, extreme precipitation events can be more frequent and intense both regionally and globally in the future. Global warming has led to variation in the precipitation types, resulting in more precipitation in the form of rainfall in some regions. In previous studies, extreme precipitation has been often studied as a whole, whether the extreme rainfall or snowfall has been discussed separately in some cases. But, only a few studies have been reported on the differences between extreme rainfall and extreme snowfall. The Clausius-Clapeyron equation hypothesis (hereafter referred to as the C-C equation) can be considered as the physical mechanism under extreme precipitation (rain and snow) events. At the same time, the atmospheric water holding capacity can be assumed to increase by approximately 7% with the increase of every 1°C in temperature under a constant relative humidity. However, there are some differences in some regions, such as most parts of Europe, North America, and the Tibetan Plateau, where the increase of extreme precipitation intensity can be much less than 7% with the increase of every 1°C in temperature, (so-called sub-C-C rate). Even some regions experience extreme precipitation intensities with the increase of temperature up to 14% (the “super-C-C” rate), such as Hong Kong and the De Beers region of the Netherlands. And even more, there is a negative relationship between extreme precipitation intensity and temperature in tropical regions. Therefore, it is necessary to discuss the relationship among extreme rainfall, extreme snowfall intensity, and temperature at various stations. In this study, the rainfall and snowfall events were separated from the wet-bulb temperature method using the data from 75 observing meteorological stations from 1961 to 2020, which has an overall accuracy of 95%. The percentile approach (95th percentile) was also used to define the extreme precipitation (rain and snow), further to determine the overall characteristics of extreme precipitation and frequency changes in this region, while the spatial variation differences between the northern and southern part in Xinjiang, as well as the response mechanisms of the intensity of extreme rainfall and extreme snowfall to temperature changes. The results show that there was an increasing trend in the amount and frequency of average annual precipitation (rain and snow) and the average annual extreme precipitation (rain and snow). The increase in the amount and frequency of rainfall, extreme rainfall, snowfall and extreme snowfall was greater in the northern region than that in the southern region (except for the frequency of rainfall). The mean contribution of extreme precipitation (rain and snow) to precipitation (rain and snow) was greater than 26%, both of which showed an increasing trend. The response of extreme rainfall and snowfall to temperature changes in both the northern and southern parts was less than the expectation of the C-C equation, i.e. the “sub C-C rate”. Once a certain temperature was exceeded, there was an inhibiting effect on the intensity of extreme rainfall and snowfall. The study will contribute to the scientific understanding of the changing characteristics of extreme precipitation events in the Xinjiang and is of great significance to the rational regulation of regional hydrological and water resources. [ABSTRACT FROM AUTHOR]

State diagram is used to determine the stability of dried and frozen foods during their processing and storage. In this study, state diagram of sardine was developed by measuring the freezing curve, glass line, solids melting line, and maximal-freeze-concentration conditions. Glass transition temperature decreased with the increase in water content and it was adjusted using a modified Gordon-Taylor equation. The glass transition of dry-solids and critical temperature were 184.1 and 12.5oC, and the model parameter of the modified Gordon-Taylor equation was estimated as 4.2, respectively. Solids melting temperature was modeled by Flory-Huggins equation; and dry-solids melting temperature and Flory-Huggins solids-water interaction parameter were determined as 199.4oC and 0.956, respectively. Freezing point of fresh sardine was observed as −1.3oC with ice melting enthalpy of 186.3 kJ/kg, and it decreased with the increase of solids due to the freezing point depression with solutes. Freezing point was adjusted by Chen equation based on Clausius-Clapeyron equation. The ultimate maximal-freeze-concentration temperatures, (T m ′) u and (T g ′′′) u were determined as −18.6 and −25.1oC, respectively and maximal-freeze-concentration solids were estimated as 0.90 g solids/g sample (i.e. un-freezable water 0.10 g water/g sample). This indicated that frozen sardines could be most stable if stored below −25.1oC, and dried fish stored below its glass transition. • Glass transition of dry-solids was observed as 184.1oC and modified Gordon-Taylor parameter was 4.2 with critical temperature of 12.5oC. • Dry-solids melting-decomposition temperature and Flory-Huggins solids-water interaction were199.4oC and 0.956, respectively. • Freezing point of fresh sardine was observed as −1.3oC with ice melting enthalpy of 186.3 kJ/kg. • Ultimate maximal-freeze-concentration temperatures were determined as −18.6 and −25.1oC, respectively. • Un-freezable water was determined as 0.10 g water/g sample. [ABSTRACT FROM AUTHOR]

A large part of the earth's surface is covered by seasonally or permanently frozen soils. Considering the negative impact of climate change, future development of such regions can be underpinned by mathematical methods for accurate analysis of heat and moisture transport in freezing and thawing soils. Reported in this paper is a novel non-local formulation of water and heat transport in unsaturated soils. The formulation uses bond-based peridynamics (PD) and consists of a set of integral–difference formulations of energy and mass conservation. Specific features of freezing/thawing soils are incorporated by a combination of van Genuthcen and Clausius–Clapeyron relations. Computational results are compared with four sets of laboratory experiments to demonstrate the efficiency of the developed approach. The model can be used to analyse the effect of water flow on heat transfer in soils during thawing of permafrost soils. Further, it can be applied in modelling climate change effects, and can be used for construction of coupled physically justified models of frost heave. • A general form of energy and water mass conservation equations is proposed. • A new bond-based Peridynamics model of unsaturated frozen soil is developed. • Agreement between the developed PD solutions and experimental results is demonstrated. [ABSTRACT FROM AUTHOR]

The addition of nanoparticles to base fuel may bring about remarkable changes in a thermodynamic process such as evaporation, due to the intensified interaction between particles and liquid molecules. In this study, the nano-fuels containing the 20 nm and 50 nm cerium oxide (CeO2) particles with the dosing levels of 50 mg·L−1 and 100 mg·L−1 were prepared using N-tetradecane (C14) as base fuel and cetyltrimethyl ammonium bromide as dispersant. The evaporation characteristics of nano-fuels were investigated via a constant temperature thermogravimetric method. The thermodynamic parameters of nano-fuel evaporation process, such as activation energy, vapor pressure and evaporation enthalpy, were calculated based on Arrhenius equation, Antoine and Langmuir equations and Clausius–Clapeyron equation, respectively. It was revealed that the particle size and mass fraction of CeO2 nanoparticles had a consistent effect on the activation energy, vapor pressure and evaporation enthalpy of nano-fuels. The activation energy required for vaporization increased with the decrease of nanoparticle size or the increase of nanoparticle mass fraction, because of the low-specific heat capacity of nanoparticles. Moreover, the vapor pressure decreased with the decrease of nanoparticle size or the increase of the mass fraction for particle. This is because the addition of nanoparticles could augment the surface tension of fuel, retarding the diffusion of liquid phase molecules into gas phase. The evaporation enthalpy of nano-fuels increased due to the Van der Waals forces between fuel molecules and nanoparticles. [ABSTRACT FROM AUTHOR]

The Clausius–Clapeyron relation and its analogs in other first-order phase transitions, such as type-I superconductors, are derived using very elementary methods without appealing to the more advanced concepts of entropy or Gibbs free energy. The reasoning is based on Kelvin's formulation of the second law of thermodynamics and should be accessible to high school students. After recalling some basic facts about the Carnot cycle, we present two very different systems that undergo discontinuous phase transitions (ice/water and normal/superconductor) and construct engines that exploit the properties of these systems to produce work. In each case, we show that if the transition temperature T tr was independent of other parameters, such as pressure or magnetic field, it would be possible to violate Kelvin's principle, i.e., to construct a perpetuum mobile of the second kind. Since the proposed cyclic processes can be realized reversibly in the limit of infinitesimal changes in temperature, their efficiencies must be equal to that of an ordinary Carnot cycle. We immediately obtain an equation of the form d T / d X = f (T , X) , which governs how the transition temperature changes with the parameter X. [ABSTRACT FROM AUTHOR]

This work investigates the magnetic properties and the magnetocaloric effect in the spin-1 Blume-Capel model. The study was carried out using the mean-field theory from the Bogoliubov inequality to obtain the expressions of free energy, magnetization and entropy. The magnetocaloric effect was calculated from the variation of the entropy obtained by the mean-field theory. Due to the dependence on the external magnetic field and the anisotropy included in the model, the results for the magnetocaloric effect provided the system with first-order and continuous phase transitions. To ensure the results, the Maxwell relations were used in the intervals where the model presents continuous variations in magnetization and the Clausius-Clapeyron equation in the intervals where the model presents discontinuity in the magnetization. The methods and models for the analysis of a magnetic entropy change and first-order and continuous magnetic phase transitions, such as mean-field theory and the Blume-Capel model, are useful tools in understanding the nature of the magnetocaloric effect and its physical relevance. [ABSTRACT FROM AUTHOR]