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In this study, Melamine–formaldehyde (MF) resins were subjected to modification with benzoguanamine (BG) to produce MF-BG resins, followed by a comprehensive analysis of their chemical composition using advanced spectroscopic techniques such as Fourier transform infrared (FTIR), 1H-NMR, and 13C-NMR spectroscopy. The flame-retardant characteristics and thermal decomposition behavior of papers impregnated with MF-BG were examined and contrasted with those treated with standard MF. In particular, the optimized MF-BG5-treated paper exhibited a Limiting Oxygen Index (LOI) value exceeding 30%, and analysis using a cone calorimeter indicated a notable decrease in parameters such as the heat-release rate (P-HRR), total heat release (THR), smoke production rate (SPR), and total smoke production (TSP) when compared to papers impregnated with standard MF. The findings from the scanning electron microscopy (SEM) analysis of the residual char following cone calorimeter experiments revealed that the MF-BG5-treated paper exhibited a denser and more uniform char formation. This phenomenon consequently limits the emission of combustion by-products and impedes the spread of flame. This study provides a feasible method for low-pressure laminates with better flame retardancy by using the BG additive up to a limit in MF resin. [ABSTRACT FROM AUTHOR]

This paper identifies physical properties of an interesterified palm‐based fat (EIEPO) that predict oil binding capacity (OBC). A 100% EIEPO sample, 50% EIEPO sample diluted with 50% soybean oil (SBO), and a 20% EIEPO sample diluted with 80% SBO were used to test how saturation level impacts OBC. All samples were crystallized using either a fast (6.4°C/min) or slow (0.1°C/min) cooling rate as well as with or without the application of high‐intensity ultrasound (HIU; 20 kHz) to generate a wide range of physical properties. Immediately after crystallization, the sample's physical properties, including crystal microstructure, solid fat content (SFC), viscoelasticity (G′, G″, and δ), melting behavior, hardness, and OBC (centrifuge method) were quantified. The samples were then stored for 48 h at 22 and 5°C and the aforementioned physical properties were measured again, with one additional measurement for the samples stored at 5°C—OBC using a filter paper method (OBCp). The results indicate that OBC can be optimized in a palm‐based fat by modifying the physical properties which was achieved via the processing conditions. Both measurements of OBC were significantly correlated with SFC, hardness, δ, and enthalpy. A model was developed to predict a sample's OBCc using the following dominant variables—SFC, hardness, peak temperature, enthalpy, and the number of crystals. These results suggest that OBC can be predicted using a sample's SFC, hardness, peak temperature, enthalpy, and number of crystals and that SFC, hardness, and enthalpy are main drivers of OBC. [ABSTRACT FROM AUTHOR]

Agricultural paper mulch is an indispensable part of modern agriculture. It had the functions of heat preservation, moisture preservation, insect resistance, disease prevention, and weed growth inhibition. In order to extend the service life of the paper mulch, we use the solution immersion method to modify the surface of the paper mulch. A super-hydrophobic paper mulch is mainly prepared by using hydrophobic silica. The static contact angle of the super-hydrophobic paper mulch with water is 160.6°. The super-hydrophobic paper mulch samples were immersed in acid solution (pH = 4.6 H2SO4) and alkaline solution (pH = 8.5 NaOH). The main instruments are contact angle tester, tensile testing machine and high-speed camera. The hydrophobic properties, mechanical properties and rebound properties of the two kinds of paper mulches were compared. The results showed that the tensile strength and droplet bounce height of the superhydrophobic paper mulch decreased after being soaked in acid or alkaline solution for 48 h. The mass loss rate of paper mulch was more significant in acid solution, but its contact angle was still greater than 145°, and it had good bounce performance. After observing the microscopic morphology of its surface, it was found that silica had a micro-rough structure on the surface of the paper mulch. The method was simple and environmentally friendly, and can alleviate the problem of poor acid and alkali corrosion resistance of the paper mulch, and had extraordinary significance for environmental protection. [ABSTRACT FROM AUTHOR]

We studied the characteristics of waste printing paper and cardboard particles in a reactor pyrolyzed by preheated agents with the aim of simulating a real case in a fixed-bed gasifier. A TGA/DSC was first used to study of the kinetics and enthalpy change of the printing paper and cardboard pyrolysis. Pyrolitic conversion was further carried out in a batch-type reactor with non-electrical heating. Syngas, tar and char were produced and characterized from printing paper and cardboard pyrolysis at 400°C, 500°C and 600°C. Different flow rates of carrier gas were applied to study the effect of residence time on the products distribution. When the flow rate increased, the relative mass change of gas agrees with that of tar. With increase in temperature, the yield of furfural, olefins and other non-aromatic compounds in tar decreased, while phenols and heavier aromatic hydrocarbons increased. The evolution of CO2, CO and other gas species in the syngas was presented. Van Krevelan diagram of chars was also presented in the paper. [ABSTRACT FROM AUTHOR]

Ammonium polyphosphate (APP) was microencapsulated with ethyl cellulose (EC) and mixed with cellulose fibers in water to form the flame-retardant paper. It was found that the original APP was quadrate with smooth surface. In contrast, its surface became rough after the EC microencapsulation, and its electronegativity and solubility were significantly decreased. Specifically, its water contact angle increased from 26.54° to 101.52°. Compared with the Kraft/APP, the limiting oxygen index (LOI) value of the Kraft/APP@EC increased from 28.7% to 31.2% at the dosage of the flame retardant of 30%, and the tensile index changed from 56.43 N·m/g to 51.98 N·m/g. Meanwhile, the thermal decomposition process changed from two stages to three stages, during which apparent decreases were observed in the peak heat release rate, the effective heat of combustion and total heat release. Moreover, the residual char weight after the paper combustion increased from 22.09% to 31.81%, the ID/IG decreased from 2.01 to 1.74, and more cross-linking bonds of O P-O-C, P-O-C, and P-O-P generated in the char residue, which proved that a denser char layer was formed. Therefore, APP@EC apparently improved the fire retardancy of the cellulose paper while the tensile strength was basically maintained. • The ammonium polyphosphate was microencapsulated with ethyl cellulose and added to the pulp to prepare flame-retardant paper. • The APP@EC particles' surface became rough, the electronegativity and solubility decreased significantly. • Cellulosic paper containing EC microencapsulated APP gained outstanding flame-retardant performance. [ABSTRACT FROM AUTHOR]

Soil organic matter (SOM) plays a central role for both the C cycle and soil functions. Plants provide the input and heterotrophic (micro)organisms are essential for the turnover. Microbial metabolism links matter and energy fluxes and generates the highest energy turnover dynamics in SOM because the organisms need both energy and matter for maintenance and growth. In this perspectives paper, we evaluate the knowledge on thermodynamic approaches potentially applicable to study the turnover of organic matter in the soil system. Thermodynamics is essential for understanding organic matter turnover in soil as turnover and storage are controlled by the energy supply to, and consumption by, microbes. Instead of just comparing the heat of combustion of compounds without considering microbial anabolism, we need to apply conventional thermodynamic state variables that can be either estimated using established thermodynamic equations, or measured empirically in soil. In particular, we can follow and quantify overall changes of enthalpies by calorimetry. Here, we suggest to apply a thermodynamic concept with the related experimental approaches of calo(respiro)metry and turnover mass balances including biomass formation. This enables us to better interpret and understand the highly variable carbon use efficiency (CUE) in a multi-substrate system such as soil and to relate this to energy use efficiency (EUE). Combining the experimental measurements of the thermodynamic state variables with mass turnover data allow prediction of whether compounds can be metabolized with energy delivery to microorganisms, or be thermodynamically stabilized under the respective redox and electron acceptor conditions. Energy balancing shows how much energy is actually used and retained in the soil, how much is emitted as heat, and how much may be stabilized due to endergonic turnover reactions. Thermodynamic stabilization should therefore be considered as basic stabilization process for organic compounds in soil. • Energy fluxes are essential to sustain active microbes contributing to soil organic matter (SOM). • Dynamic energy and matter fluxes in soil are tightly coupled. • Thermodynamics can describe microbial SOM formation and transformation. • Thermodynamic state variables allow balancing and interpreting of soil processes. • Gibbs energy gain for microbes is dominated by the electron acceptors half-reaction. [ABSTRACT FROM AUTHOR]

To counter the paper flammability, Silk fibroin-Polyquaternium-10/Melamine phosphate-SiO2 (SF-JR400/MP-SiO2) based on natural silk protein may be applied to the Dongba Paper (DBP) surface using layer-by-layer assembly. The microstructure and composition of the coating may be assessed using a scanning electron microscope, fourier transform infrared spectrometer, and X-ray photoelectron spectroscopy. The presence of the coating increases the paper combustion limiting oxygen index from 20.4 to 38.0%. Compared to the untreated DBP, TGA analysis shows that the initial decomposition temperature of the 25-layer assembly rises from 115 to 148 °C, and the residual char yield increases from 11.3 to 38.8%. XPS shows that the formation of a char on the coating surface protects the internal fibers of paper from heat feedback and consequent thermal decomposition. Analysis using cone calorimeter tests (CONE) indicates that a 25-layer assembly can reduce the peak and total heat dissipation by 88.4% and 54.7%, respectively analysis suggests that silk protein may function as an agent to accelerate the coating, formation of a protective. This work provides technical implications to produce flame-retardant handmade paper. [ABSTRACT FROM AUTHOR]

In the paper, the impact of paper-mill sludge dried at 75 °C (PS) on cement hydration is being analysed. The used specimens were made of CEM I 42.5 R cement and the added PS replaced 0%, 5%, 10% and 15% by mass of cement. The results of calorimetric measurements of the mixtures and the compressive strength were analysed (W/(C + PS) = 0.35). SEM and XRD tests were carried out after 3, 14, 28 and 56 days of curing W/(C + PS) = 1. PS was found to extend the induction period of the cement hydration and delay the time of the secondary heat release effect, especially in specimens with the highest content of the PS. The total heat release (after 96 h) measurement results showed that the highest total heat evolved from specimens without the PS. The total liberated heat gradually increased with the increase in the PS content in the cement paste mixture. In the specimens with 15% of PS, the total heat release decreased by 20%, as compared to the control specimen without the additive. XRD test results revealed that the standard minerals listed below were formed in cement stone: ettringite, calcite, portlandite, and calcium aluminium silicate hydrate. SEM tests revealed significant changes in cement stone microstructure caused by the increase in the PS in cement paste. The compressive strength of specimens with PS waste was found to be considerably lower in the initial stage of hardening; however, when samples hardening time is increased up to 56 days, the difference between the values of compressive strength for specimens 5% of PS and the control specimens decreases. [ABSTRACT FROM AUTHOR]

The CALPHAD framework is built on assumption that all phases have a well-defined free energy over all accessible composition, temperature and pressure conditions. Unfortunately, it is common for phases to exhibit mechanical instabilities in at least some range of conditions, thus precluding direct experimental measurements and hindering computational efforts. A pragmatic solution has often been to extrapolate free energies from stable region into the unstable regions, but extrapolations from different systems that share a common phase may not agree and extrapolated free energies can unintentionally lie below the free energy of stable phases. Computational approaches that aim to directly calculate the free energy of unstable phases offer a promising avenue to address these issues. Among them, the recently proposed “inflection detection” scheme lies on a strong theoretical footing. We provide further support for this approach by demonstrating that it yield free energies that agree very well with the widely used SGTE (Scientific Group Thermodata Europe) data for pure elements. This finding suggest that it may be possible to get the best of both worlds: obtain a theoretically justified definition of the free energy of mechanically unstable phases and preserve much of existing empirical standards for the assignments of such free energies. [ABSTRACT FROM AUTHOR]

Abstract: Large numbers of soil samples are routinely analyzed using methylene blue (MB) titration to determine clay content. Although, the MB filter paper spot test titration is simple, it is labor-intensive, subjective, and leaves no record for subsequent re-examination. Preliminary thermometric monitoring of the titration indicated a switch from endothermic to exothermic reaction during titration. We examined this nearly universal property of physicochemical processes as a potential replacement method to automate the MB clay titration, making use of literature data. We translated the isothermal enthalipmetric titration of montmorillonite using MB by Rytwo and Ruiz-Hitzky to an adiabatic thermometric titration (2003). The plot of temperature versus titrant volume gave two intersecting linear segments dependent on the titrated percentage of the clay''s cation exchange capacity (CEC). The MB filter paper spot test endpoint reflects the first excess MB that persists in the solid suspension, which also happens to be a function of the clay''s CEC. The spot test endpoint is correlated to the thermometric indicator point and, for montmorillonite, the two are related by an exact factor of two. Although this factor will naturally be dependent on the clay minerals in the samples, the analyses show that the thermometric indicator titration method is a viable replacement for the spot test. The proposed automation is commonplace as it is practiced with other types of titrations. [Copyright &y& Elsevier]

Traditional fire warning sensors usually work under directly fire attack or relatively high temperature and overlook electrical safety. Therefore, it is imperative to develop an efficient early fire warning sensor with the circuit safety during flame exposure. Herein, a flame-retardant paper with thermosensitive fire-alarm response and self-cutting performance is proposed. The paper consists of shape memory thermoplastic polyurethane (SMPU) and MXene is prepared via facile electrospinning and vacuum filtering process, which can be utilized as a fire early alarm triggered by the shape memory behavior of SMPU. The SMPU/MXene paper can provide a stable detection signal and ideal early fire warning responses when the ambient temperature is above transition temperature of SMPU. Meanwhile, it is possible for SMPU/MXene paper to serve as a fuse to protect the fire alarm system from fire attacking based on the electro-activated property. Compared to SMPU paper, SMPU/MXene paper showed superior fire retardancy with a rapid self-extinguishing performance, as well as 66.0% and 49.8% reduction in peak of heat release rate (pHRR) and total heat rate (THR), respectively. This work provides a novel perspective for designing early detection fire-alarm sensors and fire-protection applications. [ABSTRACT FROM AUTHOR]

Improved methods of analysis and new quantum chemical calculations have been applied to the results of earlier gas-phase electron diffraction (GED) studies of digallane to give what is judged to be the most realistic structure available to date. The principal distances (ra3,1in pm) and interbond angles (∠a3,1in deg) are as follows (t= terminal, b= bridging): r(GaGa) 254.9(2), r(Ga−Ht) 155.0(6), r(Ga−Hb) 172.3(6), ∠Ga−Hb−Ga 95.4(5), and ∠Ht−Ga−Ht128.6(9). Scrutiny of the IR spectra of solid Ar matrices doped with the vapour above solid samples of gallane at temperatures in the range 190-220 K reveals the presence of not only Ga2H6as the major component, but also a significant fraction of the monomer GaH3. Analysis of the relative proportions of the two molecules evaporating from the solid at different temperatures has led to a first experimental estimate of 59 ± 16 kJ mol−1for the enthalpy change associated with the reaction Ga2H6(g) → 2GaH3(g). Together with a value of 52 kJ mol−1delivered by fresh calculations at the MP2 level, this implies that the stability of the dimer with respect to dissociation has been overrated by earlier theoretical treatments. [ABSTRACT FROM AUTHOR]

The cycloaddition of tetracyanoethylene oxide (TCNEO) with benzene and benzene derivatives, and the subsequent evolution of the corresponding cycloadducts is theoretically investigated using DFT and highly correlated ab initiocalculations. Both the relative reactivity of the different aromatic compounds, as well as the regioselectivity of the cycloaddition is explained in light of the theoretical study. Insights in the formation of arylmalononitriles, which gives potential synthetic applications to this process, are also offered. [ABSTRACT FROM AUTHOR]

About 7% of people's daily time is spent in taking vehicles between office and home. Besides, with the improvement of the living standard in today's society, people's requirements for a comfortable environment inside the car are constantly increasing and this must rely on an effective vehicle air conditioner to maintain the comfort of the cabin environment. In general, a vehicle air conditioner uses the air-mixing mode to regulate the temperature control system. In this mode of operation, the compressor needs to work continuously, which is extremely energy consuming. The vehicle's air conditioner is greatly affected by the inner and outer heat load, which are generated therein. Furthermore, the heat load is instantly changeable. Therefore, only when the controller can adapt to the feature of heat load, then we can find the optimal control method, thus enabling the vehicle's air conditioner to interact with the actual heat load to supply the balanced cooling capacity and, as a result, create the most comfortable environment inside the cabin with minimum energy consumption. For this purpose, we bring up in this paper a low-energy-consumption smart vehicle air-conditioning control system to detect total heat load, which can change the vehicle's air-conditioning capacity mode to maintain the average temperature at 25.2°C∼26.2°C and the average humidity at 46.6%∼54.4% in the cabin. When the inner heat load is stable, the rest times of the compressor can reach 16∼23 times per hour, which attains a rate of fuel saving around 21%∼28%. With the proposed architecture, the purpose of the low-energy-consumption vehicle air-conditioning system can be achieved, which, at the same time, creates a comfortable environment inside the cabin. [ABSTRACT FROM AUTHOR]

The experimental measurement of density and enthalpy of mixture for two binary liquid mixtures of n-tridecane or n-tetradecane with decalin was reported in this paper. The measurements were conducted at a temperature range of 293.15–323.15 K and at 303.15 K using calorimeter C80. The mixtures were analyzed at various proportions, including the entire composition range and dilute solutions. The excess molar volume (VE) and excess molar enthalpy (HE) of mixtures were calculated and fitted using the Redlich–Kister equation. The paper observed the expansion phenomenon for the VE at all temperatures, including over the entire composition range and dilute solutions. Additionally, the HE exhibited endothermic behavior at the studied temperature range and composition range. The Prigogine–Flory–Patterson (PFP) theory was utilized to predict both thermodynamic properties, namely the VE and HE. The results obtained using the PFP theory were compared with those obtained using the Treszczanowicz and Benson association (TB) model for VE and with the NRTL, Wilson, and Flory models for HE. The PFP model, which employed a single-fitted parameter to describe VE, demonstrated satisfactory performance in predicting VE. Conversely, the Treszczanowicz and Benson association (TB) model yielded relatively poor results in fitting VE. However, the NRTL, Wilson, PFP, and Flory models exhibited good performance in predicting HE. [ABSTRACT FROM AUTHOR]

Atlantic time‐mean heat transport is northward at all latitudes and exhibits strong multidecadal variability between about 30°N and 55°N. Atlantic heat transport variability influences many aspects of the climate system, including regional surface temperatures, subpolar heat content, Arctic sea‐ice concentration and tropical precipitation patterns. Atlantic heat transport and heat transport variability are commonly partitioned into two components: the heat transport by the Atlantic Meridional Overturning Circulation (AMOC) and the heat transport by the gyres. In this paper we compare four different methods for performing this partition, and we apply these methods to the Community Earth System Model Large Ensemble at 34°N, 26°N and 5°S. We discuss the strengths and weaknesses of each method. The four methods all give significantly different estimates for the proportion of the time‐mean heat transport performed by AMOC. One of these methods is a new physically‐motivated method based on the pathway of the northward‐flowing part of AMOC. This paper presents a preliminary version of our method that works only when the AMOC follows the western boundary of the basin. All the methods agree that at 26°N, 80%–100% of heat transport variability at 2–10 years timescales is performed by AMOC, but there is more disagreement between methods in attributing multidecadal variability, with some methods showing a compensation between the AMOC and gyre heat transport variability. Plain Language Summary: Scientists often want to quantify how much heat is transported by the Atlantic Meridional Overturning Circulation (sometimes called the "Conveyor Belt" circulation) and how much heat is transported by the ocean's gyres. This paper compares some different methods for estimating the heat transport by the overturning circulation and by the gyres, including a new method that has not been used before. There are significant differences in the results of each method, and here we discuss the strengths and weaknesses of each method. The heat transport at about 30°N has a lot of variability: all the methods agree that short‐timescale variability (2–10 years timescale) is due to the overturning circulation. All methods agree that more than half of the time‐mean heat transport across 30°N is performed by the overturning, but the exact proportion varies from 65% to 120% depending on the method we use. Key Points: We compare four diagnostics for Atlantic Meridional Overturning Circulation (AMOC) heat transport that partition the flow into mass‐conserving gyre and overturning componentsA new physically‐motivated method is compared with the standard method that relies on zonally averaging the temperature and velocity fieldsAll four methods yield different estimates of the fraction of time‐mean heat transport performed by AMOC [ABSTRACT FROM AUTHOR]

Today, the World Health Organization has declared a global health emergency, caused by the Monkeypox outbreak. In the monthly analysis for June, 3500 cases have been reported in 50 countries around the world. In the analysis for July, more than 30000 cases have been reported in 75 countries. Thus, in the circumstances of the continuing COVID-19 pandemic, the appearance and dynamics of spreading of Monkeypox is alarming. In this paper, for the first time, elemental composition of Poxvirus, Monkeypox virus, and Vaccinia virus have been reported. Additionally, thermodynamic properties have been reported for nucleic acids, nucleocapsids, and entire virus particles. The similarity in chemical composition and thermodynamic properties of the analyzed viruses has been used to explain the crossed immunity to Poxviruses. Finally, binding thermodynamic properties have been reported for the Vaccinia virus. [ABSTRACT FROM AUTHOR]

The Pd-D codeposition system1 has been investigated by means of isoperibolic calorimetry. It is shown that high rates of excess enthalpy generation are achieved at relatively short times by using this methodology (as compared to the rates achieved when using "massive" electrodes2-8) and the system also shows the early effects of the development of "positive feedback." In view of the marked variation of the rate of excess enthalpy generation with time, the data analysis must be restricted to the evaluation and use of the differential heat transfer coefficients. It is shown that the heat transfer coefficient given for this system by the group at the New Hydrogen Energy Laboratories, Sapporo, Japan, had to be incorrect as it was less than the value calculated from the Stefan-Boltzmann coefficient and the radiant surface area. Furthermore, the value differed from that evaluated for experiments when using Pd-B alloy electrodes in the same cell. These disparities are attributed to the inappropriate evaluation of the integral heat transfer coefficients. Nevertheless, positive rates of excess enthalpy generation are derived even when using the impossibly low value of the heat transfer coefficient. It is also shown that the recombination of the gases evolved in the cell (which is frequently invoked to explain excess enthalpy generation) leads to the impossible conclusion that the "lower bound" heat transfer coefficient exceeds the "true" value. [ABSTRACT FROM AUTHOR]

A 30-year (1980–2010) climatology of the major variables and terms of the transformed Eulerian-mean (TEM) momentum and thermodynamic equations is constructed by using four global atmospheric reanalyses: the Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2); the Japanese 55-year Reanalysis (JRA-55); the European Centre for Medium-Range Weather Forecasts (ECMWF) interim reanalysis (ERA-Interim); and the Climate Forecast System Reanalysis (CFSR). Both the reanalysis ensemble mean (REM) and the differences in each reanalysis from the REM are investigated in the latitude–pressure domain for December–January–February and for June–July–August. For the REM investigation, two residual vertical velocities (the original one and one evaluated from residual meridional velocity) and two mass streamfunctions (from meridional and vertical velocities) are compared. Longwave (LW) radiative heating and shortwave (SW) radiative heating are also shown and discussed. For the TEM equations, the residual terms are also calculated and investigated for their potential usefulness, as the residual term for the momentum equation should include the effects of parameterized processes such as gravity waves, while that for the thermodynamic equation should indicate the analysis increment. Inter-reanalysis differences are investigated for the mass streamfunction, LW and SW heating, the two major terms of the TEM momentum equation (the Coriolis term and the Eliassen–Palm flux divergence term), and the two major terms of the TEM thermodynamic equation (the vertical temperature advection term and the total diabatic heating term). The spread among reanalysis TEM momentum balance terms is around 10 % in Northern Hemisphere winter and up to 50 % in Southern Hemisphere winter. The largest uncertainties in the thermodynamic equation (about 50 %) are found in the vertical advection, for which the structure is inconsistent with the differences in heating. The results shown in this paper provide basic information on the degree of agreement among recent reanalyses in the stratosphere and upper troposphere in the TEM framework. [ABSTRACT FROM AUTHOR]

Existing research on the analysis heat pump operation generally focuses on the efficiency of doing work while ignores heat loss in the transfer process. Hence, heat pumps are often studied based on theory of minimum entropy production. However, this theory is rarely applied to optimizing heat transfer process without heat work conversion. Taking the air source heat pump hot water supply system of a hotel building as an example, this paper simulates the heat production, power and COP of the air source heat pump during operation based on the theory of entransy and entransy dissipation proposed by Professor Zengyuan Guo. The findings show that heat pump operates best at inlet water temperatures of 293 K and 298 K, with a COP of 4.8. In the water at a temperature of 298 K, water temperature can be adjusted by the function of heating capacity between 30 kW and 40 kW to minimize the system's entransy dissipation, where the system's unit power consumption reaches its minimum at 9 kW, corresponding to an entransy dissipation of 245.4 kJK. This study provides a good research idea to optimize the thermal power conversion process using the theory of entransy and entransy dissipation. [ABSTRACT FROM AUTHOR]

Paper membranes have long been used in an enthalpy exchanger. However, there has been a continuous concern on the durability or the anti-bacterial performance. In this study, heat and moisture transfer characteristics of a recently-developed PE/PA (polyethylene/polyacetate) composite membrane was investigated as a possible substitute to the paper membrane. Results showed that the diffusion coefficients of the PE/PA membrane (7.7 × 10−10 m2/s to 1.8 × 10−9 m2/s) were higher than those of the paper membrane (1.8 × 10−11 m2/s to 6.0 × 10−11 m2/s). Furthermore, the diffusion coefficient increased as relative humidity increased, reached a maximum at 50 % to 60 % and then decreased. For PE/PA membrane, the sorption constant increased as temperature increased, which was the reversed trend to the paper membrane. Successful prediction of the moisture transfer effectivenesses of the separate pseudo-counter flow enthalpy exchangers further strengthened the validity of the obtained diffusion coefficients. [ABSTRACT FROM AUTHOR]

The Modified Genetic Algorithm scheme, presented in Paper I to model crystal structures in organic compounds (MGAC), is applied here to test its performance in the determination of a polymorphic crystalline structure of benzene that has been observed at 25 Kbar. This polymorph, named here benzene II, is not a global minimum of the energy or even close to any of the local minimum determined using the energy evolution of benzene structures described in the previous paper. The benzene II structure corresponds to an enthalpy minimum. This paper shows that it is possible to use the MGAC procedure, modified to use the minimization of the enthalpy instead of the energy in the GA (Genetic Algorithm) selection process, to find this high pressure structure of benzene. [ABSTRACT FROM AUTHOR]

The Brakes contact surface temperature rises sharply when vehicle braking by friction, so vehicles are generally equipped with ventilated brake discs for cooling. However, the recirculation zone in the ventilated brake disc passage severely blocks fluid flow. In order to improve the convective and heat dissipation performance of the ventilated brake disc, this paper aims to introduce an optimized slotted vane geometry to improve the heat dissipation performance of ventilated brake discs. Therefore, three structural parameters of slot width, slot inclination and number of vanes were selected as optimization variables, and the optimization objective was to maximize the mass flow rate and convection heat transfer coefficient. And then, combined with the RSM and NSGA-II for optimization. The results showed that the optimized slotted vanes effectively suppressed the recirculation zone in the flow passage and made the airflow distribution more uniform. The optimal characteristic parameters after optimization are N = 36,θ = 56.38°, H = 12.7 mm. The CFD calculation results are consistent with the experimental results, and the Nu error obtained is about 2.6%. Within the given speed range, compared with experimental data of the straight vane brake disc, the total heat dissipation rate of the optimized brake disc is increased by 9%, the heat dissipation rate in the channel was increased by 5.6%, and the pumping capacity is increased by 12%. [ABSTRACT FROM AUTHOR]

The magnetohydrodynamics (MHD) model of the alternating current (AC) arc is complex, so a simplified equivalent heat source (EHS) model can be used to replace the complex model in studying the AC arc's thermal characteristics and cable fire risk. A 2D axisymmetric AC arc MHD simulation model in the short gap of a copper-core cable is established in this paper. The AC arc voltage and current obtained by the model are consistent with experiments. The AC arc's heat source distribution obtained by the MHD model is fitted to obtain the heat source function Q of the AC arc. Q is divided into 16 independent segmented heat sources, and a correction matrix is constructed to optimize the segmented heat sources. A neural network and a genetic algorithm give the prediction model and the optimal correction matrix of the segmented heat source. The EHS model optimized by the optimal correction matrix can obtain a minimum temperature error of 5.8/4.4/4.2% with the MHD model in different AC arc peak currents 2/4/6 A. The probability of a cable fire is calculated by using AC arc's optimized EHS model when different numbers of AC arcs are generated randomly in AC half-waves. The EHS model can replace the complex MHD model to study the thermal characteristics of AC arcs and quickly calculate the probability of a cable fire caused by random AC arcs. [ABSTRACT FROM AUTHOR]

This paper presents the results of numerical simulations of heat transfer in a tube with a protective chromium layer on the inner surface made of steel, with different shrinkage temperatures. Shrinkage in the steel is an unfavorable phenomenon because it causes cracks in the chrome coating. The cracks contribute to the peeling of the protective material on the inner surface of the tube. Wear and damage to the chrome layer significantly shortens the tube's service life. The influence of the type of steel with medium carbon content on heat transfer for a sequence of ten, thirty, and sixty heat impulses was examined. Simulations were carried out for two selected steels with clearly different shrinkage temperatures, i.e., 30HN2MFA and X37CrMoV5-1 (1.2343). In 30HN2MFA steel, the shrinkage effect occurred at a temperature of approx. 750 °C, while in X37CrMoV5-1 steel it occurred at a temperature of approx. 870 °C. In the computational model, 30 cross-sections of the three-meter-long tube were analyzed. A time-dependent heat transfer coefficient was calculated in each zone. Heat transfer simulations were carried out using COMSOL version 6.1 software. This paper shows that for X37CrMoV5-1 steel, the shrinkage temperature on the inner surface of the tube was reached after approx. 60 heat impulses, while for 30HN2MFA steel, it was reached after approx. 30. The greatest differences in the number of impulses occurred for a pipe with a 200 µm thick chrome layer. [ABSTRACT FROM AUTHOR]

In industrial processes involving both heat and mass transfer, the enthalpy or total energy difference, not the temperature difference, is a more comprehensive driving-force potential for the design of heat exchanger systems, such as cooling towers. However, current enthalpy methods based on the Merkel integral require numerical integration with implied linear distributions of water temperature. If the cooling range of the cooling tower is relatively small, the outcome of the integration may carry little error. However, for a large cooling range and a substantially increased temperature, the error involved may be significant. Like log-mean temperature difference, a log-mean enthalpy difference method may require only the inlet and outlet conditions without prior knowledge of the enthalpy distributions of the fluids within the heat exchanger. The known Berman's enthalpy difference method requires correction factors and was derived based on the linearization of the interfacial enthalpy and the enthalpy difference between the interfacial moist air and the bulk moist air without underlying interpretation to demonstrate that the method could be broadly used. In this paper, an equivalent enthalpy model is proposed, and the log-mean enthalpy difference is derived without retaining model assumptions. The derived method is compared with some results of Merkel's method from literature with excellent agreement. Thus, the work in this paper would open up the possibility for broad uses of the log-mean enthalpy difference method for many industrial processes involving both heat and mass transfer. [ABSTRACT FROM AUTHOR]

In thermodynamic theory, free energy (i.e., available energy) is the concept facilitating the combined applications of the theory's two fundamental laws, the first and the second laws of thermodynamics. The critical step was taken by Kelvin, then by Helmholtz and Gibbs—that in natural processes, free energy dissipates spontaneously. With the formulation of the second law of entropy growth, this may be referred to as the dissymmetry proposition manifested in the spontaneous increase of system/environment entropy towards equilibrium. Because of Kelvin's pre-entropy law formulation of free energy, our concept of free energy is still defined, within a framework on the premise of primacy of energy, as "body's internal energy or enthalpy, subtracted by energy that is not available". This primacy of energy is called into question because the driving force to cause a system's change is the purview of the second law. This paper makes a case for an engineering thermodynamics framework, instead, to be based on the premise of the primacy of dissymmetry over free energy. With Gibbsian thermodynamics undergirded with dissymmetry proposition and engineering thermodynamics with a dissymmetry premise, the two branches of thermodynamics are unified to become classical thermodynamics. [ABSTRACT FROM AUTHOR]

Emulsion explosives have become a hot topic in various studies due to their explosive combustion characteristics and detonation performance under different environmental pressures. The thermal safety of an emulsified matrix was studied with ignition energy as the characterization. A minimum ignition energy test experimental system for emulsion matrices was established in this research. The system simulated the occurrence of hot spots inside emulsion matrices using an electric heating wire. The effect of bubbles on the thermal safety of the emulsified matrix was studied by adding expanded perlite additive to the emulsified matrix. This study investigated the variation trend in the minimum ignition energy of the emulsion matrix under the coupled effect of bubbles and ambient pressure using the orthogonal experimental method. The impacts of two factors on the thermal safety of the emulsion matrix were studied at different hot-spot temperatures. Coupled analysis experiments were conducted on emulsion matrices containing 0%, 1.5%, and 3% expanded perlite under pressure environments of 1 atm, 2 atm, and 3 atm. The critical hot-spot temperature of the emulsion matrix significantly decreases with increasing bubble content at 1 atm and 2 atm pressures, as revealed by intuitive analysis and analysis of variance. However, at 3 atm of pressure, the bubble content in the emulsion matrix has no significant effect on its critical hot-spot temperature. The results show that the thermal safety of the emulsified matrix decreases with the increase in the content of expanded perlite and environmental pressure, and the influence of environmental pressure is more significant than that of the bubble content. This paper's research content serves as a reference for a safe emulsified matrix and as an experimental basis for establishing a production line for developing new equipment. [ABSTRACT FROM AUTHOR]

Ocean observational gridded products are vital for climate monitoring, ocean and climate research, model evaluation, and supporting climate mitigation and adaptation measures. This paper describes the 4th version of the Institute of Atmospheric Physics (IAPv4) ocean temperature and ocean heat content (OHC) objective analysis product. It accounts for recent developments in quality control (QC) procedures, climatology, bias correction, vertical and horizontal interpolation, and mapping and is available for the upper 6000 m (119 levels) since 1940 (more reliable after ∼ 1957) for monthly and 1°×1° temporal and spatial resolutions. IAPv4 is compared with the previous version, IAPv3, and with the other data products, sea surface temperatures (SSTs), and satellite observations. It has a slightly stronger long-term upper 2000 m OHC increase than IAPv3 for 1955–2023, mainly because of newly developed bias corrections. The IAPv4 0–2000 m OHC trend is also higher during 2005–2023 than IAPv3, mainly because of the QC process update. The uppermost level of IAPv4 is consistent with independent SST datasets. The month-to-month OHC variability for IAPv4 is desirably less than IAPv3 and the other OHC products investigated in this study, the trend of ocean warming rate (i.e., warming acceleration) is more consistent with the net energy imbalance at the top of the atmosphere than IAPv3, and the sea level budget can be closed within uncertainty. The gridded product is freely accessible at 10.12157/IOCAS.20240117.002 for temperature data (Cheng et al., 2024a) and at 10.12157/IOCAS.20240117.001 for ocean heat content data (Cheng et al., 2024b). [ABSTRACT FROM AUTHOR]

We present here a novel experimental setup able to measure the enthalpy of sublimation of a given compound by means of Piezoelectric Crystal Microbalances (PCM). This experiment was performed in the TG-Lab facility in IAPS-INAF, dedicated to the development of TGA sensors for space measurements, such as detection of organic and non-organic volatile species and refractory materials in planetary environments. In order to study physical-chemical processes concerning the Volatile Organic Compounds (VOC) present in atmospheric environments, the setup has been tested on Dicarboxylic acids. Acids with low molecular weight are among the components of organic fraction of particulate matter in the atmosphere, coming from different sources (biogenic and anthropogenic). Considering their relative abundance, it is useful to consider Dicarboxylic acid as "markers" to define the biogenic or anthropogenic origin of the aerosol, thus obtaining some information of the emission sources. In this work, a temperature controlled effusion cell was used to sublimate VOC, creating a molecular flux that was collimated onto a cold PCM. The VOC re-condensed onto the PCM quartz crystal allowing the determination of the deposition rate. From the measurements of deposition rates, it was possible to infer the enthalpy of sublimation of Adipic acid, i.e. ? Hsub: 141.6 ± 0.8 kJ mol-1, Succinic acid, i.e. 113.3 ± 1.3 kJ mol-1, Oxalic acid, i.e. 62.5 ± 3.1 kJ mol-1 and Azelaic acid, i.e. 124.2 ± 1.2 kJ mol-1 (weight average values). The results obtained are in very good agreement with literature within 10% for the Adipic, Succinic and Oxalic acid. [ABSTRACT FROM AUTHOR]

In this paper, a new designed silicon-containing nitrogen and phosphorus flame-retardant system containing ammonium polyphosphate, modified molecular sieve and methylcellulose was used to prepare the flame-retardant corrugated cardboards (FRCCB). The samples before and after treatment were tested for combustion and thermal stability using vertical burning test (VBT), limiting oxygen index (LOI), cone calorimetric test (CCT) and thermogravimetry (TG). To further analyze the flame-retardant properties of the flame-retardant system, the microstructure, surface elements and functional groups of the materials were characterized by the scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR). The mechanical properties of the samples were tested to analyze the effect of flame-retardant treatment on the strength. The VBT and LOI tests showed that the samples after the flame-retardant treatment were able to self-extinguish after ignition, achieving the flame-retardant B-1 grade. The CCT tests showed that the total heat release of treated samples was reduced by 49.90%, and the total smoke production was decreased by 27.64%. TG tests showed that the thermal decomposition temperature of FRCCB decreased but the residual carbon content increased largely. FTIR tests showed that the functional group changed at different temperatures. After flame-retardant treatment, a dense carbon layer was formed on the surface of the treated sample, including N, P, Si and Cu, measured by SEM and EDS. Combining with various characterization methods, the flame-retardant system can retard flame by releasing nonflammable gases, forming covers and catalyzing char formation. [ABSTRACT FROM AUTHOR]

The transport and storage of heat by the ocean is of crucial importance because of its effect on ocean dynamics and its impact on the atmosphere, climate and climate change. Unfortunately, limits to the amount of data that can be collected and stored means 5 that many experimental and modelling studies of the heat budget have to make use of mean datasets where the effects of short term fluctuations are lost. In this paper we investigate the magnitude of the resulting errors making use of data from OCCAM, a high resolution global ocean model. The model carries out a proper heat balance every timestep so any imbalances that are found in the analysis must 10 result from the use of mean fields. The study concentrates on two areas of the ocean affecting the El Nino. The first is the region of tropical instability waves north of the equator. The second is in the upwelling region along the equator. It is shown that in both cases, processes with a period of less than five days can 15 have a significant impact on the heat budget. Thus analyses using data averaged over five days or more are likely to have significant errors. It is also shown that if a series of instantaneous values is available, reasonable estimates can be made of the size of the errors. In model studies such values are available in the form of the datasets used to restart the model. In experimental studies they may be in the form of individual 20 unaveraged observations. [ABSTRACT FROM AUTHOR]

We used a collocation method between XBT and CTD/OSD (Ocean Station Data including bottle cast and low resolution CTD) from WOD05 (1° x 2° x 15 days) to statistically correct the XBT fall rate. An analysis of the annual median bias on depth showed that it is necessary to apply a thermal correction linked to probe calibration error, a second order correction on the depth as well as a depth offset representing measurement errors during XBT deployment. We had to separate data in several categories: shallow and deep XBT and deployment sea temperatures (below or above 10°C). We also processed separately XBT measurements close to Japan between 1968 and 1985 due to large regional biases. Once the corrections have been applied, the analysis of heat content signal is derived from corrected XBT. From this analysis, we confirm that the maximum heat content in the top 700 meters found during the 70's in early papers can be explained by the XBT biases. In addition, a trend of 0.32.1022 J/year is observed between the period 1970 and 2008. [ABSTRACT FROM AUTHOR]

The combustion process of traditional diesel engines is mainly determined by the injection timing of diesel. There is a trade-off relationship between the soot and NOx (nitrogen oxides) during this combustion process, making it difficult to reduce these two emissions simultaneously. The use of methanol can not only solve the above problem, but also replace some fossil fuels. However, the effects of methanol injection into the intake duct on the flame propagation in diesel/methanol dual-fuel engines is not yet clear, and there is relatively little research on it. The effects of methanol addition on the combustion process of diesel/methanol dual fuel (DMDF) were achieved based on a modified optical engine in this paper. One injector is installed on the intake inlet to inject methanol, and the other injector is installed in the cylinder to inject diesel in two stages before the top dead center of compression. There are three tests conducted separately in this paper. Firstly, the effects of the methanol ratio (40%, 50%, 60%, and 70%) on the combustion process are investigated, with the total heat remaining unchanged. Secondly, the effects of the pre-injection mass of diesel (20%, 30%, 40%, and 50%) on the combustion process are investigated, which keeps the total diesel mass unchanged. Finally, the effects of the total mass of diesel on the combustion process are investigated while maintaining the mass of methanol unchanged. The dual-fuel combustion process is recorded by a high-speed camera. A combustion analyzer and other equipment were used to analyze the combustion. The results showed that CA10 is delayed, the pressure and the heat release rate (HRR) are reduced, and the number of pixels of the KL factor (KL) decreases significantly with the increasing methanol ratio. CA10 and CA50 are advanced, the pressure and HRR decrease, and the KL increases when the mass of pre-injected diesel increases. CA10 and CA50 are advanced, respectively, and CA90 is postponed due to the increase in diesel mass. The pressure and HRR increase, and the KL increases when the total mass of diesel increases. [ABSTRACT FROM AUTHOR]

In this paper, the finite volume method was used to numerically study the heat transfer and flow of double-pipe heat exchangers (DPHE) under static and ocean motion conditions. The ocean motion is simplified as a harmonic oscillation with the center of the DPHE as the axis of rotation. In addition the flow direction and the inlet Reynolds number, the effects of amplitude and period ontal heat transfer coefficient, pump power and thermal performance factor were also analyzed quantitatively. The results showed that as the heat exchanger oscillates, the total heat transfer coefficient, and pump power exhibit a periodic change and the period is half of the oscillating period of the heat exchanger. The total heat transfer coefficients for all oscillating DPHE are higher compared to static conditions, reaching a maximum improvement of 9.84% at low Reynolds numbers. The total heat transfer coefficient and pump power of DPHE under oscillation are significantly regular, positively correlated with amplitude and negatively correlated with period. When the amplitude exceeds 0.5 rad/s, the oscillatory condition has thermal performance improvement for the oscillating DPHE with the inner tube with low Reynolds number and the outer tube with high Reynolds number. In the optimum condition, the thermal performance of the inner and outer tubes is improved by 5.01% and 1.48%, respectively. The thermal performance coefficient of DPHE hardly changed when the period exceeded 5 seconds. The results herein provide a theoretical basis for predicting the development of offshore double-pipe heat exchange equipment. [ABSTRACT FROM AUTHOR]

Biothermodynamics is a discipline which has developed intensely during the last 50 years. Thermodynamic properties have been reported for humans, animals, plants, and microorganisms. However, this paper reports for the first time the empirical formula and thermodynamic properties for insects. Thermodynamic properties can be applied in research on thermodynamic interactions between organisms and their environment, as well as between organisms themselves. This paper reports for the first time the empirical formula and reactions of catabolism, biosynthesis and entire metabolism for Bombyx mori (domestic silk moth), as well as the thermodynamic properties of Bombyx mori. It is shown that growth of Bombyx mori is tightly related to catabolism of carbohydrates and lipids, which represents the driving force for the entire metabolism. [ABSTRACT FROM AUTHOR]

A third paper [[3]] modelled the performance of a cogeneration system in a greenhouse and evaluates its economic efficiency versus the European country and the kind of cultivation. The first [[1]] analysed the long-term economic performance of some projects in the Mediterranean climate of Athens, Greece, while the second [[2]] focused on the short-term, detailed economic performance of a cogeneration system in a hospital. The most favourable conditions for cogeneration use were found in Italy and the United Kingdom, with average spark ratios of more than 4, resulting in an annual total cost of heating energy close to -7 EUR/m SP 2 sp per year. [Extracted from the article]

Induction heating of asphalt concrete has the characteristics of high crack repair efficiency and environmental sustainability. However, the uneven temperature distribution and local overheating obstruct its widespread application. Therefore, this paper conducted a pixel-level quantitative analysis of the temperature distribution characteristics and local overheating phenomenon on both the upper and side surfaces of asphalt concrete with different steel fiber (SF) contents after continuous heating. The temperature distribution was visualized by three-dimensional (3D) heat maps and violin maps. The uniformity of temperature was analyzed by the slope absolute value of the linear fitting results and the ratio of the interquartile range to the range. Results indicated that high SF content accelerated the heating rate of asphalt concrete but decreased the temperature uniformity. Localized overheating caused thermal expansion damage in asphalt mixtures, and the sample with 10% SF had both 304.2°C (maximum) and 79.7°C (minimum) upper surface temperatures at 60 s of heating, with local structural disintegration of the mixture. Higher heating uniformity and faster heating rates were achieved for samples with 6% SF content. The heating rate decreased with increasing heating time. The upper surface of the sample with 8% SF can be heated up the fastest (2.28°C/s). It is recommended that the maximum temperature of the upper surface be controlled during induction heating to avoid thermal damage. This proposal provides a reference for the practical application of induction heating technology. [ABSTRACT FROM AUTHOR]

A common belief is that any closed, counterclockwise cycle on a pV diagram represents a refrigerator or heat pump. It has been established that this is not the case, but previous papers on this topic have made unnecessary assumptions about the temperatures of the energy reservoirs and about how the system exchanges energy with the reservoirs. Relaxing these assumptions leads to a wide array of unexpected behaviors. In some cases, the same pV cycle can be a heat pump, a cold pump, or a Joule pump simply by changing how the system is connected to the reservoirs. This paper explores the strange world of counterclockwise cycles. Editor's note: In this paper, author Randall Knight explores the rich behavior of counterclockwise thermodynamic cycles. A counterclockwise cycle can function as a heat pump or refrigerator, but this is not the only possibility. The choice of thermal reservoirs and the choice of which reservoir heat is absorbed from and exhausted to during the cycle affect the coefficient of performance and even the basic function of the device. The author illustrates these possibilities through an analysis of counterclockwise Carnot, Kelvin, Brayton, and Stirling cycles. The analysis includes interesting possibilities, such as a cycle that operates with a single reservoir, as well as practical applications like the role of heat exchangers. The surprising results of this analysis will likely be of interest to anyone who has studied thermodynamics, and the material can easily be incorporated into any course that includes thermodynamics, from introductory physics to graduate study. [ABSTRACT FROM AUTHOR]

In this paper, we explore different prognostic methods to account for skin sea surface temperature diurnal variations in a coupled ocean–atmosphere regional model of the Mediterranean Sea. Our aim is to characterise the sensitivity of the considered methods with respect to the underlying assumption of how the solar radiation shapes the warm layer of the ocean. All existing prognostic methods truncate solar transmission coefficient at a warm-layer reference depth that is constant in space and time; instead, we implement a new scheme where this latter is estimated from a chlorophyll dataset as the e -folding depth of solar transmission, which thus allows it to vary in space and time depending on seawater's transparency conditions. Comparison against satellite data shows that our new scheme, compared to the one already implemented within the ocean model, improves the spatially averaged diurnal signal, especially during winter, and the seasonally averaged one in spring and autumn, while showing a monthly basin-wide averaged bias smaller than 0.1 K year-round. In April, when most of the drifters' measurements are available, the new scheme mitigates the bias during nighttime, keeping it positive but smaller than 0.12 K during the rest of the monthly averaged day. The new scheme implemented within the ocean model improves the old one by about 0.1 K, particularly during June. All the methods considered here showed differences with respect to objectively analysed profiles confined between 0.5 K during winter and 1 K in summer for both the eastern and the western Mediterranean regions, especially over the uppermost 60 m. The new scheme reduces the RMSE on the top 15 m in the central Mediterranean for summertime months compared to the scheme already implemented within the ocean model. Overall, the surface net total heat flux shows that the use of a skin sea surface temperature (SST) parameterisation brings the budget about 1.5 Wm-2 closer to zero on an annual basis, despite all simulations showing an annual net heat loss from the ocean to the atmosphere. Our "chlorophyll-interactive" method proved to be an effective enhancement of existing methods, its strength relying on an improved physical consistency with the solar extinction implemented in the ocean component. [ABSTRACT FROM AUTHOR]

Nuclear thermal propulsion is an evolving technology that can be utilized for long-distance space travel. This technology yields the advantage of a high thrust and specific impulse, but requires an examination of the potential design adjustments necessary to enhance its feasibility. The development of nuclear thermal propulsion requires a comprehensive understanding of the system-level behavior during transient and steady-state operation. This paper extends our previous research by including the proper handling of turbomachinery with multi-channel thermal hydraulic simulations only for steady-state solutions. The system-level approach presented here enables the treatment of the turbopump components through non-dimensional analysis that eliminates the assumption of constant efficiencies. All the other components within the system (e.g., reflector and core) can be discretized to multiple channels and layers, in which the full thermal hydraulic solution is established. The approach chosen here enables the realistic modeling of the propellant flow within the expander cycle by capturing the pressure losses, mass flow rate splits, and enthalpy gain for various operational conditions. The verification of the package is completed through point comparisons of previous investigations into similar system designs. Furthermore, sensitivity studies are used to benchmark the capabilities of the package and investigate solution variations due to the perturbation of operational conditions and regimes. The sensitivity studies performed here are important to capture variation in flow characteristics (e.g., temperature, pressure, mass flow rates) for different design objectives such as the thrust and specific impulse. This work demonstrates that system-level simulations lacking multi-channel capability and proper turbomachinery treatment may yield higher uncertainties in understanding the engine's response and characteristics to changing various requirements. This is extremely important when screening the design space of such propulsion systems and when transient simulations are required. [ABSTRACT FROM AUTHOR]

Coal spontaneous combustion (CSC) is one of the main disasters in the process of coal mining. In this paper, the important role of high-latent heat phase change material CH3COONa·3H2O (SAT) in controlling CSC was studied and compared with common inhibitors (NaCl, CaCl2, ascorbic acid (VC)). The thermal performance characteristics of SAT were revealed by the C80 micromanometer, and the effects of different inhibitors on the thermal behavior of Shengli lignite were analyzed and compared. Furthermore, the gas–solid coaxial fixed bed measurement system was used in conjunction with the Pfeiffer online mass spectrometer, to design the natural temperature rise experiment of coal after the heating interruption in the same programmed temperature rise interval, investigating the effects of different inhibitors on the temperature and gas production in the process of coal oxidation. The results show that the heat absorption effect of SAT is more significant than common inhibitors, which not only improves the heat absorption rate of the samples but also increases the total heat absorption of the sample by 236.6 J·g−1 compared with the raw coal. In the programmed temperature rise experiment, the maximum temperature point of the SAT-inhibited coal sample is reduced by 15.5% compared with raw coal, the time to reach the maximum temperature point is delayed by 20.5%, and the SAT inhibitor effectively inhibits the production of CO and CO2 gases. The method described in this paper provides a new idea for the prevention and control of CSC. [ABSTRACT FROM AUTHOR]