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Glazed roofs are increasingly used in modern buildings. Integrating multiple-glazing envelope with PCM as a passive solar utilization system can reduce energy consumption of building by latent heat storage. However, the traditional PCM-filled glazed envelope still has a poor thermal performance and thermal regulation as well as climate adaptability. In this work, an innovative reversible multiple-glazing roof integrated with two PCM, silica aerogel and low-e glass was proposed and a numerical study was performed to explore its thermal performance across the season in cold climate (Daqing, China). The new roof with and without low-e glass were investigated, and compared with the traditional air-filled multiple-glazing roof. The influence of melting temperature and thickness proportion of two PCM on thermal performance of the roof was analyzed. And an energy-economy comparison between the new roof and the traditional roof in full life was performed. The results indicate that the new glazed roof can provide excellent thermal performance in both summer and winter, and has the economic feasibility. Taking the traditional roof as a reference, the energy saving rate can achieve 14.08% in summer and 33.74% in winter, respectively, and the total cost is saved 217 Yuan/m2 in full life.

To overcome the leakage of phase change materials (PCMs) above melting temperature, PCMs are commonly encapsuled by chemically crosslinked networks, which bring the issues of reparability, reprocess-ability and recyclability making for the environment pollution and resource waste. Herein, a reversible aromatic disulfide is adopted to form dynamic epoxy networks which not only encapsulate polyethylene glycol (PEG) as the shape-stabilized PCMs (SSPCMs) but also address the issues about the un-recyclability of traditional SSPCMs. The PEG was well encapsulated and uniformly dispersed in disulfide-based epoxy due to the elaborate molecular design. The obtained SSPCMs (named EXAP2) shows typical solid–solid phase transitions characteristic and thermal reliability with high latent heat value of 82.7 J/g. Besides, the EXAP2 exhibit dynamic performance and can be reprocessed by hot press via the disulfide bonds exchange reaction above topology freezing temperature (Tv). And the reprocessed EXAP2 exhibits close phase change properties with the original sample, implying the reprocessing does not affect the crystalline structure and encapsuling capability of disulfide crosslinked networks. This strategy prove a significant way for fabricating the novel SSPCM with recyclability, reprocessability and reliability.

All available thermodynamic properties and phase diagram data of the Sn-O system at 1 atm total pressure were critically evaluated and optimized to obtain a set of thermodynamic functions of all stable phases. The discrepancies among available experimental phase diagram data were resolved. In addition, new experiments were attempted to determine the melting temperature of SnO2 using sealed Pt capsules. It was confirmed that the melting temperature of SnO2 is higher than 1700 °C, which was taken into account in the present optimization. The Gibbs energies of the liquid solution of SnO-SnO2 and all solid compounds were obtained. A new phase diagram at 1 atm total pressure was constructed from the optimized Gibbs energy functions of all phases.

High-melting-point borides are attractive for structural and functional materials used in extreme environments. However, their poor sinterability due to their high melting point and strong covalent bonding have prevented their further applications. In this study, a new sintering process, called transient liquid-phase diffusion sintering (TLPDS), has been developed for high-melting-point borides. TiB2 compacts were fabricated by spark plasma sintering at 50 MPa for 15 min at temperatures of 1300 and 1600 °C via TLPDS of TiB2 powder with a eutectic TiB–Ti powder as the sintering aid, prepared via mechanical alloying (MA). Differential scanning calorimetry results indicated that the melting temperature of the obtained sintering aid was lower than its equilibrium melting point. MA of the sintering aid suppressed the open pore fraction to one-third of that in the compact sintered with the aid prepared without MA when sintering at 1300 °C. We also propose a possible mechanism for TLPDS of TiB2.

The effect of Li2O on the crystallization properties of CaO-Al2O3-SiO2-Li2O-Ce2O3 slags was investigated. With increasing the Li2O content, LiAlO2 and CaCeAlO4 were the main crystalline phases. LiAlO2 formed for the charge compensating of Li+ ions to [AlO45−]-tetrahedrons, and CaCeAlO4 formed as a result of the charge balance of Ce3+ ions, Ca2+ ions, and [AlO69−]-octahedrons. Increasing the content of Li2O to 10%, the crystallization temperature was the highest, and the incubation time was the shortest. The crystallization ability was strong due to the three factors of strengthening the interaction between ions and ion groups, decreasing the polymerization degree, and increasing the melting temperature. Further increasing the content of Li2O, the crystallization performance was obviously suppressed, because the melting temperature and the force between the cations and the anion groups decreased.

The goal of this study was to understand the impact of high-shear wet granulation (HSWG) processing conditions on product attributes for a tablet formulation containing the non-ionic surfactant TPGS. The use of TPGS in oral solid drug products has been reported to be challenging due to the low melting temperature of TPGS. In addition, literature on TPGS-based HSWG formulations, especially practical processing and scale-up knowledge, is limited. Presented here is an extension of this TPGS application in a tablet formulation, with a focus on the HSWG processing and scale-up across different granulators. To understand the processing space for this TPGS-based HSWG formulation, two consecutive studies were conducted with different objectives. First, an exploratory study was conducted to understand the impact of extreme processing conditions on product attributes. Subsequently, a factorial design of experiment (DoE) study assessed the separate contributions and interactions from HSWG processing variables. The outcome of both studies led to a successful process scale-up and product transfer from lab to commercial development using different granulators. The TPGS-based formulation was demonstrated to provide robust downstream processing (improved flowability and reduced segregation potential) within a wide HSWG operating space, while having a minimal impact on product performance across different granulators.

Main objective of the presented research is the life time prediction of self-supporting flame-sprayed Al2O3- and Al2O3 -ZrO2 -TiO2-materials under constant load. The characteristic life time and its scatter were derived from stable crack growth tests and Weibull-statistics including the four-point-bending and ball-on-three-balls method. The potential life time was estimated in order to assess room-temperature handling and long term storage of self-supporting flame-sprayed alumina components. In terms of flexural strength, energy release, and subcritical crack growth parameters, distinct differences between both materials were shown. In turn, the characteristic life times only barely deviated from each other. From that the conclusion was drawn that life time performance under constant load application is governed by the characteristic flame-spray microstructure. However, advantages in the flame-spray processing of Al2O3 - ZrO2 -TiO2 are still given, attributed to its lower melting temperature.

Temperature is an essential parameter in various fields, including chemistry, biology, environmentology, industry, and medical sciences. Currently, temperature detection using practical colorimetric methods has not been sufficiently explored. In this study, we established a polyethylene glycol-functionalized graphene oxide (PEG-GO)-based colorimetric thermosensor using guanine (G)-rich DNAzyme (Dz) and peptide nucleic acid (PNA). Dz served as the template DNA for thermosensitive nanostructures and as catalytic DNA for colorimetric assays. The peroxidase-like activity of Dz was completely inhibited after hybridizing with PNA, which could be recovered in the presence of PEG-GO in a thermosensitive manner, resulting in colorimetric temperature visualization. The temperature-sensing range of this system could be simply tuned by designing a PNA strand based on the melting temperature of the Dz/PNA duplex of interest. Smartphone assistance in this colorimetric platform enabled more precise, sensitive, and practical recognition of fine temperature changes. Moreover, this design permitted recall of the target temperature, enabling the visualization of the temperature at a later point. This robust system has the potential to be a tool for rapid temperature-sensing applications, such as in health diagnostics and food safety, and it could become a valuable resource for basic and applied nanobiotechnology research.

Woody biomass is a renewable source offering high potential for production of bio-fuels, -chemicals and -energy. During the outdoor storage of biomass biodegradation processes take place, which leads to mass reduction up to 30 wt%. To avoid these mass losses, the biomass was mixed with Ca(OH)2 in different ratios. To ensure, that this additive does not negatively influence further thermo-chemical conversion of biomass (e.g. by fluidized bed combustion), the spruce and poplar ash with and without additive was tested using ash melting microscopy. It was demonstrated that all the characteristic temperatures (DT, HT, FT) were significantly higher than the thermo-chemical conversion process temperatures in a fluidized bed. Thus it could be pointed out that the addition of Ca(OH)2 does not negatively influence ash melting behaviour, ash melting temperature respectively.

The volume dependence of the Gruneisen parameter has been used to calculate the pressure dependence of melting temperature using Lindemann law. The volume dependence of the Gruneisen parameter for some transition metals viz, Cu, Ni, Pd, and Pt has been determined using Shanker reciprocal relationship between γ and the ratio of pressure and bulk modulus. In this study, volume dependence of the Gruneisen parameter for some transition metals using the Stacey and Davis formulations for infinite pressure. The results for γ have been found similar from both the formulations given by Shanker and Stacey-Davis. The values of melting temperature are calculated and different pressures and Equation of state compared with the available data reported in the literature.

Ever since the start of the electronic age, soldering has been an important interconnecting method in microelectronic packaging. Since the 1960 s, development of information technology (IT)-infrastructure has witnessed rapid advancement owing to development of novel electronic equipment. This, in turn, has led to growth and progression of industries and improved human lifestyle. Present-day electronic gadgets are highly sophisticated and comprise several components. Sn–Pb based solder alloys have always delivered excellent results, offering several amazing benefits, namely, easy handling, low melting temperature, good working condition, ductility, and exceptional wetting on Cu and its alloys. Owing to its lethal and harmful effects on health and the environment, the US Congress introduced the legislation on the limited use of Pb in 1990. Consequently, alternatives to lead free solders are being developed for last three decades. This literature review discusses the effect of Gallium, Phosphorus and Nickel addition on solder alloy microstructure and mechanical properties.

This paper proposed a new approach (density approach) to predict the thermal stability of CNTs. This approach is utilized to find the melting temperature and thermal stability of armchair-type SWCNT having chiral vector (10, 10) and length 59.03 A using molecular dynamics (MD) simulations. Also, the effect of length and chirality on the thermal stability of armchair-type SWCNT is investigated. Atomistic modelling of SWCNTs is done using Visual Molecular Dynamics (VMD), and the subsequent MD simulations are performed using the open-source code Large-Scale Atomistic/Molecular Massively Parallel Simulator (LAMMPS). Based on the results, it is concluded that increasing the length of the SWCNTs decreases the melting temperature of the SWCNTs; whereas, increasing the chirality of the SWCNTs causes an increase in the melting temperature and thus, improves the thermal stability. The results obtained from the proposed approach are verified with the results reported in the literature as well as with the results predicted by other approaches, such as radial distribution function g(r) and atomic configuration.

To enable removal of emulsifying salts (ES) in cheese powder production, the structural differences due to absence of ES on the physical and functional properties of high fat cheese powders were studied. Homogenization and pH adjustment were used to mimic ES effects. Feeds without ES showed protein aggregates and fat clusters. Non-homogenized feed without ES resulted in powder with larger particles, darker and cohesive. All parameters were improved when homogenization was applied. No significant differences were observed in powders from homogenized feeds after pH adjustment. Melting temperature and relative crystallinity were higher for the fat in powder with ES due to better fat emulsification and structure within the powder. Crystal polymorphs (α, β and β’) were present in all cheese powders, β' being the dominant form. ES powder presented faster dispersion and stronger interaction with water. Thus, the absence of ES impairs the powder quality and affects the fat behavior.

In the present study, a theoretical comparative work is done to calculate the variation of melting temperature in nanomaterials by using two quantum models i.e. Lu model and Jiang model and the expression of melting temperature calculated with the help of best model is extended to calculate the variation of Debye temperature and thermal expansion coefficient with size and shape of nanomaterials. The melting temperature and Debye temperature are observed to increase as the diameter of nanomaterials is increased and thermal expansion coefficient decrease with increase in the diameter of nanosolid. The results obtained from the given models are compared with the experimental values to judge the best-suited model for the study of the thermodynamic properties of nanosolids. The available experimental results are found very close to the results from the Jiang model and then Debye temperature and thermal expansion coefficient are calculated with the help of Jiang model.

In the present study, a thermodynamic model is formulated to determine the melting temperature of metals with increasing pressure using an equation of state (EoS). The model is applied to determine the melting temperature of Cu, Au, Ag, Zn, Cd, In and Pb at high pressure. The model formulation is based on Goyal and Gupta EoS which follows Stacey's criteria and is valid in high pressure conditions and also it does not involve any adjustable parameter. The volume compression, bulk modulus and its first order pressure derivative is determined using the EoS with an increase in pressure. It is observed that melting temperature show increase with the increase in pressure, however, variation is not linear. The comparison of present computed results of melting temperature under pressure is done with the theoretical and experimental results available and good consistency between the compared results is observed. This study helps in understanding the quantitative effect of pressure on the melting behavior of metals. The melting temperature at high pressures can also be predicted using the present formalism.

Although lipid droplets are believed to play an important role in cryopreservation of mammalian embryos and oocytes, the effect of low temperatures on lipid droplets and related mechanisms of cryodamage are still obscure. Here, we provide Raman spectroscopy evidence of lipid separation inside the lipid droplets in domestic cat oocytes during slow freezing. It was shown that at −25 °C lipids coexist in two separated phase states inside lipid droplets. The scale of detected domains was a few micrometers size. We also found that under certain conditions these areas have a specific spatial distribution. Lipids with high melting temperature are distributed near the surface of lipid droplets while fusible lipids are located deep inside. Raman spectroscopy was found to be a prospective approach to study inhomogeneity of lipid phase transition in cells and to reveal effects of this inhomogeneity on cryopreservation of biological cells.

The suitable thermodynamics and sorption properties of 2LiBH4-MgH2 system inspired us to explore the effect of KH on this system. The addition of 5 mol% KH to this system didn't show any significant effect on desorption temperature, however, an interesting peak shift to lower temperature was observed that corresponds to the melting of 2LiBH4-MgH2. This gave us a sign of eutectic phenomenon that has been observed in 2LiBH4-KBH4 system recently. To explore it in more detail, a series of (2LiBH4-MgH2)x-(KH)1-x system was examined and a pseudo-binary phase diagram for this system has been plotted. Using this phase diagram, the eutectic composition has been identified for x = 0.45 with the lowest melting temperature at 79 °C.

To improve the utilization of mulberry seed with its extremely high annual yield and stress the importance of mulberry seed oil, mulberry seed oil and α-linolenic acid (ALA) were used to prepare structural lipids (SLs) with a balanced ratio of n-6/n-3 polyunsaturated fatty acids (PUFAs) in a microfluidic enzyme reactor. When the lipase amount was 1/3 g/cm3, the substrate molar ratio was 1:5, the flow rate was 2 μL/min and the reaction temperature was 50 °C, the n-6:n-3 ratio of SLs was 1.11:1, and the content of ALA reached 42.0%. The prepared SLs that contained 89.7% PUFAs had a lower melting temperature (−24.2 °C) and a lower crystallization temperature (−40.1 °C) compared with mulberry seed oil, and had three stages of weight loss during processing. These results implied that the SLs were more stable than mulberry seed oil, more beneficial to human health, easier to absorb and convenient to store.

The melting lines of graphite and liquid carbon have been studied for a long time. However, numerous controversies still remain in this field; for instance, different experiments give different melting temperatures. In this work, we explore the melting lines of graphite and graphene by means of classical and ab-initio molecular dynamics. We show that the empirical models developed on the basis of experimental data (AIREBO potential, Tersoff potential and some others) fail to reproduce the properties of liquid carbon properly. The models fitted to ab-initio data (LCBOPII and GAP) give much better results. However, both types of empirical models and ab-initio simulations evidence the presence of smooth structural crossover in liquid carbon. We also show that the “melting” of graphene discussed in previous works on computer simulation is indeed sublimation and propose a novel method to simulate the melting of graphene: simulation of graphene sheet in argon atmosphere. The melting temperature of graphene in argon atmosphere appears to be close to the melting temperature of graphite.

In the current investigation, aluminium matrix composite (AMC) was successfully fabricated by liquid melt method and the effect of stir casting (SC) parameters namely Temperature (Temperature), Stir Speed S (SS) and Stir Time (ST) on the properties was studied using Taguchi L9 orthogonal array experimental design. The melting temperature of SS and ST were selected as input parameters and the properties such as 'ρ', hardness and compressive strength (CS) were treated as responses. From signal to noise (SN) Ratio analysis, it is witnessed that the higher Temperature (850°C), S (600 rpm) and ST (15 min) is needed to attain the better Density (ρ), compressive strength (CS) and hardness of the composite. From the ANOVA analysis, SS and ST were determined as highly contributing parameters to disturb the properties of the composites. Additionally a confirmation test was carried out with the optimum parameter for validation of the Taguchi results

International audience; Recombinant adeno-associated virus (AAV) vectors have evolved as the most promising technology for gene therapy due to their good safety profile, high transduction efficacy, and long-term gene expression in non-dividing cells. AAV-based gene therapy holds great promise for treating genetic disorders like inherited blindness, muscular atrophy, or bleeding disorders. Multiple naturally occurring and engineered AAV serotypes exist, which differ in capsid sequence and as a consequence in cellular tropism. Individual AAV capsids differ in thermal stability and have a characteristic melting temperature (Tm), which enables serotype-specific discrimination of AAV vectors. Differential scanning fluorimetry (DSF) combined with a dye-like SYPRO Orange (SO-DSF), which binds to hydrophobic regions of unfolded proteins, has been successfully applied to determine the Tm of AAV capsids. Here, we present DSF measurement of intrinsic fluorescence signal (iDSF) as a simple alternative method for determination of AAV capsid Tm. The study demonstrates that DSF measurement of intrinsic fluorescence signal is a simple, accurate, and rapid alternative to SO-DSF, which enables characterization of AAV capsid stability with excellent precision and without the need of SO or any other dye.

Thermal behaviour of Multiple Phase Changing Materials (PCMs) is investigated using Physical Model consisting of a tube enclosed by multiple layers of Phase Changing Materials (PCMs) having different thermo physical properties and melting temperature. Heat Transfer Fluid (HTF) is allowed to flow from the tube to transfer and absorb heat from the Phase Changing Materials (PCM). Finite element model (FEM) is investigated to find the cumulative energy stored during charging and discharging cycle. Numerical investigations results shows that use of multiple Phase Changing Materials (PCMs) can greatly enhance thermal energy storage of latent Heat Thermal Energy Storage (LHTES) unit as compare to a single Phase Changing Materials (PCMs).

Previous investigations of building free cooling using PCM were conducted at moderate/high temperature differences during PCM charging and discharging. This is not the case in fresh air free cooling where the PCM melting temperature should be low and close to the fresh air cooling temperature. The present study experimentally investigates fresh air free cooling with small temperature difference between air and the PCM melting temperature. The PCM plates’ behaviors in transient scenarios are examined during the charging and discharging process. The results showed that a complete solidification cannot be achieved during night in case of minimal temperatures difference. The effects of fresh air flow rate and outdoor temperatures on the discharging and charging processes, energy saving and the number of the PCM plates needed to satisfy the fresh air requirements are investigated. The results show the decrease of the discharge time and the increase of the number of the PCM plates with increasing the fresh air flow rate and the outdoor air temperature. The discharge time decreases by 17 and 25% by increasing the air temperature from 32 to 36 °C and increasing the air flow rate from 89 to 134 L/s, respectively. The energy saving decreases with increasing the time from the start of the discharging processes. The numbers of the needed PCM plates are studied, determined and correlated in terms of the air flow rates and the outdoor air temperature. Keywords: Free cooling, Fresh air, PCM plates, Discharging time, Incomplete solidification, Energy saving

Bee venom (BV) is a biotoxin with biologically active peptides which have cell lysis and hemolytic activity properties. These properties can be affected under different storage conditions or during the production process. In present study, we investigated effects of a number of physicochemical factors, including temperature, pH, UV radiation, ultrasound waves and storage time on hemolytic activity of BV. Maximum absorption and melting temperature of BV solution were obtained as 280 nm and ~70 °C, respectively. Cell hemolysis 50 (CH50) -concentration of BV that can lyse 50% of red blood cells- was determined as 0.94 μg/ml at ambient temperature. CH50 was shown not to be importantly varied at temperature up to 60 °C, pH value 2 to 13 and under UV/ ultrasound radiation. Storage at −20, 6 and 25 °C for 6 months made about 2.5, 35 and 1000 times increase in CH50. From the results, it may be concluded that BV is a relatively resistant hemolytic agent and can be used in a variety of laboratory research and product manufacturing methods.

Most of numerical methods developed for the photothermal transfer researches of the paraffin-containing glazed windows adopt the gray-body model, in which the spectrum properties of glass and paraffin are generally not taken into account, even though scholars are aware of the fact that glass and paraffin are spectrum selective. Therefore, in this work, a one-dimensional photothermal model that accounts phase dependent thermophysical properties and spectrum dependent optical properties was developed based on the finite difference method, which is utilized to study the heat transfer through the glazed units incorporating paraffin. The results of the established model including non-gray characteristics of glass and paraffin with different spectrum bands were compared with the experimental results in terms of transmittance and temperature. It was observed that 4-band spectrum can accurately simulate the heat transfer process. Then, the photothermal performance of the double-layer glazed windows was studied with the verified model for different melting temperatures of paraffin under summer conditions and paraffin layer thicknesses under both summer and winter conditions, and the transmitted energy from the window units for the considered parameters was quantified. The results showed that inappropriate selection of melting temperature or paraffin layer thickness may defeat the purpose of energy saving. For the studied climatic conditions, the photothermal performance of the paraffin-containing glazed window is better when the melting point of paraffin was 18–26 °C, and the recommended paraffin layer thicknesses is 6–12 mm considering the transmitted energy.

Diamond retains original crystal form and large elastic stiffness up to very high temperatures, and strengthens considerably under high pressures. These remarkable characters dictate its behaviors under extreme loadings such as those in laser-heated diamond anvil cells (LHDACs) or giant planetary interiors. Here we report surprising findings from ab initio molecular dynamics simulations revealing that diamond's mechanical strengths reduce precipitously at elevated temperatures, by 50% at 3000 K, despite that its elastic parameters remain little changed. Our results also unravel an extraordinary shear-induced reduction of melting temperature of diamond under ( 111 ) [ 11 2 ¯ ] shear strains by as much as 1150 K, greatly altering its pressure-temperature ( p − T ) phase diagram when shear deformations exist. These new benchmarks offer crucial insights for elucidating extreme mechanics of diamond at high p - T conditions, advancing fundamental knowledge with major implications for LHDAC operation and planetary modeling.

The melting behavior of Al Si nanolayers with two different thicknesses (4 and 6 nm) confined by thin AlN layers (thickness: 3 nm) was investigated experimentally and simulated using molecular dynamics. The experimental study showed a noticeable decrease in the melting temperature of both systems, resulting in the presence of Si-enriched Al Si protrusions on the free nanomultilayer surface, forming at temperatures of T ≥ 673 K for 4 nm and T ≥ 723 K for 6 nm Al Si nanolayers, respectively. To study the mechanism of melting, as well as to explain the experimental observations, molecular dynamics simulations were performed. These revealed that silicon plays a great role in the melting process (melting always starts at the Al/Si interface and is strictly controlled by the diffusion of silicon atoms). Based on calculated non-equilibrium concentration of Si in melted Al Si nanolayers, the phase diagram for confined Al Si nanolayers was derived. Also, a mechanism of liquid outflow was proposed to explain the localized character of the melting observed experimentally.

The increasing popularity of phase change materials (PCM)-enhanced building products has initiated a scientific discussion concerning specific aspects of their applicability. This study aspires to provide justified answers to the research question of the optimal position of PCM into the building envelope, with emphasis on vernacular buildings, as well as to enlighten aspects of the appropriate melting behaviour of PCM materials. Parameters directly affecting the operation of the PCMs, namely their position within the building envelope, the external environmental conditions and the prevailing interior environmental conditions, have been investigated under diverse climatic conditions with the use of finite element method (FEM). The probability density function (PDF) of the temperature distribution at specific locations within the building envelope, at which realistically PCM layers can exist were derived, revealing the fact that in the case of non-conditioned indoor spaces, the PCM layer should actually be incorporated into the inner surface of the wall. The analysis was also conducted for different orientations and locations of the European continent, providing sufficient answers concerning the appropriate melting temperature of PCMs in the case of non-conditioned buildings. The environmental assessment of building envelopes incorporating PCM building products has also been examined, delivering the energy pay-back time of the PCM-enhanced building products.

Molten carbonate fuel cells (MCFCs) are regarded as the closest fuel cell to commercialization due to their high capacity and energy efficiency. However, they are operated at a high temperature (620 °C or higher), where liquid electrolyte loss occurs during operation; hence, their lifetime is limited. For the long-term operation of MCFCs, it is essential to develop a novel method to replenish the electrolyte during operation. However, it is very difficult to directly inject the electrolyte, (Li0.62K0.38)2CO3, into each unit cell of the stack unless it is supplemented through liquid or gas phase at low temperature. It was verified whether LiI and KI, which have low melting points and high vapor pressures, could replenish the lost electrolyte in MCFCs. In this study, the LiI and KI injected into the unit cell in liquid phase showed a similar tendency to the Li/K carbonate electrolyte. This is because LiI and KI react with the CO2/O2 gases supplied to the cathode during MCFC operation to form Li/K carbonate electrolytes.

Using the nanocrystal RP-model, the state equation of the bcc molybdenum with account of size and shape was calculated. On the basis of this equation the isobaric dependence of the melting temperature on size and shape was obtained at P = 0. It is shown, that the stronger the shape of a nanocrystal deviates from the most energetically effective one, the bigger the size of the nanocrystal at the crystallization start point. Approximation of such points for various shapes made it possible to determine the size dependence of crystallization start temperature.

Melting temperature has great influence on the high temperature properties and working temperature limits of ultra-high temperature ceramics (UHTCs) In order to bypass the challenge in the measurement of ultra-high melting points, this paper proposed a novel method to predict UHTCs melting temperature via machine learning. A dataset including more than ten thousand melting temperature data has been established, which covers 8 elements and most of the known non-oxide UHTCs. We built up an element to ceramic system framework by back propagation artificial neural network (BPANN) with the accuracy approaching to 90% and the correlation coefficients approaching to 0.95. Our work provides a probability to get the high accuracy melting temperature of UHTCs, and a more convenient way to develop novel materials with higher working temperature. The given case of melting temperature prediction of Hf-C-N ceramics proves the generality of the artificial neural network (ANN). An inter-validation of melting temperature prediction using our network with materials thermodynamics and density functional theory (DFT) has been demonstrated, indicating that our network is of powerful prediction ability.

An energy saving way for electronics cooling during peak demand is represented by phase change materials (PCMs), which could maintain the temperature of the electronic equipment at low values by using the latent heat of melting without requiring any power input. Among the organic PCMs, paraffins are widely available in a large range of melting temperatures. This paper explores the possible use of three paraffins with different melting temperatures. Each paraffin is embedded in three different aluminum foams, having approximately the same volumetric porosity (92–93%), but different linear porosity (5, 10 and 40 pores per linear inch). The system made of foam and paraffin is electrically heated from one side by applying three different heat fluxes (10, 15 and 20 kW m−2). Results are given in terms of temperature distribution both of the heated side of the foams and of the paraffin inside the foams, and the effects of the melting temperature of the paraffins and of the linear porosity of the foams are highlighted. In addition, an empirical correlation is proposed to model the paraffin melting phenomenon.

Soybean oil-based organogel was structured using monostearin, and the organogel had a gel-sol melting temperature of 44.0 °C. Loading amount of hesperidin in soybean oil-based organogels could be about twice as much as metastable solubility of hesperidin in soybean oil. Organogel-in-water Pickering emulsion was formed using the soybean oil-based organogel as the oil phase and ovotransferrin (OVT) fibrils as the emulsifier. Visual observation indicated that organogel-based Pickering emulsions stabilized by OVT fibrils (40 mg/mL) at oil fractions of 0.50–0.85 had excellent storage stability and could withstand three cycles of freeze-thaw treatments. Conventional oil-in-water Pickering emulsion was prepared as control to better understand impact of organogel incorporation on freeze-thaw stability, and conventional Pickering emulsion was formed using soybean oil as the oil phase and OVT fibrils as the emulsifier. Freeze-thaw stability of organogel-based Pickering emulsions was better than that of conventional Pickering emulsions (without organogel) stabilized by OVT fibrils. In vitro digestion study revealed that organogel-based Pickering emulsion could improve both the extent of lipolysis and hesperidin bioaccessibility when compared with organogel. This study demonstrates the feasibility of formulating novel food-grade organogel-based Pickering emulsions with high nutraceutical loading, excellent freeze-thaw stability and improved nutraceutical bioaccessibility.

Non-centrosymmetric borates K 7 CaR 2 (B 5 O 10 ) 3 have been synthesized by solid state reaction and successfully grown by the top seeded solution growth method using K 2 O-B 2 O 3 -CaF 2 flux. IR, Raman, absorption spectra as well as data on melting temperature for the crystals were obtained. Optical properties like UV absorption edge and SHG intensity were compared with KH 2 PO 4 (KDP)and K 7 CaY 2 (B 5 O 10 ) 3 .

Incorporating PCMs into traditional building envelops is an effective way to minimise indoor temperature fluctuations and maximise thermal comfort in summertime. PCMW is of particular interest due to its ease of installation. This paper presents a theoretical analysis in which both outdoor air temperature and solar radiation are considered to predict the optimal melting temperature of an internal PCMW for passive indoor temperature control. Key factors influencing the selection of optimal melting temperature are studied including outdoor temperature, solar radiation, window size, air change rate (ACH), and external wall and window U-values. A case study was carried out on a lightweight building using real weather data for the summer months in the UK. The simulation was developed in EnergyPlus with the potential to reduce energy use while maintain the desired internal temperatures determined. The optimal melting temperature was found to be 23.4 °C during summer in the UK from a theoretical analysis, which showed good agreement with the numerical simulations performed. In summer, the percentage energy savings can be as high as 40% compared with a similar building without PCMWs and the period which temperatures are maintained within the thermal comfort range can be improved by up to 7.2%.

Several Eu(III) complexes [(Eu(L1)(tta)2(H2O)]∙CF3SO3, Eu(L2)(NO3)3 and Eu(L3) with L1 = N, N′-bis(2-pyridylmethylidene)-1,2-(R,R+S,S)-cyclohexanediamine, L2 = N, N′-bis(2-quinolylmethylidene)- 1,2-(R,R+S,S)-cyclohexanediamine, L3 N-quinolyl-N,N′,N′-trans-l,2-cyclohexylenediaminetriacetic acid and tta = 2-thenoyltrifluoroacetyl-acetonate] and one Y(III) complex [(Y(L1)(tta)2(H2O)]∙CF3SO3] have been embedded, with a different degree of efficiency, in Poly(lactic-co-glycolic acid) (PLGA) matrix by using two different composition [Poly(lactic(50%)-co-glycolic acid(50%), briefly PLGA 50:50 and Poly(lactic(75%)-co-glycolic acid(25%), briefly PLGA 75:25], giving nanoparticles characterized by a monodispersed distribution of the size (diameter around 200 nm). The [Eu(L1)(tta)2(H2O)]∙CF3SO3 shows the most efficient Eu(III) luminescence (ɸTot = 25%) when embedded in PLGA 75:25. The release of the complex over the time in aqueous buffered solution has been followed by means of the decrease of Eu(III) luminescence and it is faster upon increasing the temperature to 37 °C, in particular for the PLGA 50:50 system, whose melting temperature (Tm) is lower (33 °C) than both the Tm of PLGA 75:25 (38 °C) and the basal one.

A concept of low-power research reactor (LPRR) with innovative design features is recently proposed by Korea Atomic Energy Research Institute (KAERI) in South Korea. A conventional UO2-Zircaloy 4 fuel rod is proposed to be used as a driver fuel for the operation since it is advantageous to employ the conventional fuel rod in terms of sustainable long-term operation and cost-efficiency of the LPRR. The fuel rod for the given core specification was designed in detail. The performance analysis for UO2-Zircaloy 4 fuel rod was conducted to show its irradiation behaviors with the modification of FRAPCON code which is utilized for the commercial UO2 fuel performance analysis. Temperature distribution from fuel pellet centerline to bulk coolant was estimated, in which fuel centerline temperature at the axial peak power location was much lower than fuel melting temperature. The design analysis for the fuel safety in terms of rod internal pressure and cladding hoop stress was addressed to confirm the applicability of the fuel rod in the LPRR.

Annealing offers a facile and green approach to the modification of starch. This study was the first to investigate the effect of annealing on the properties of waxy rice starch nanoparticles (SNPs). The spherical morphology of SNPs hardly changed after annealing, and the nanoscale size of the SNPs was maintained in the range of 50–120 nm. The relative crystallinity of modified SNPs increased from 53.71% to 63.46% after annealing at 55 °C for 48 h. The annealing treatment increased the melting temperature from 78.3 °C to 95.7 °C, but decreased the melting range from 30.8 °C to 25.3 °C. The increased 1047 cm−1:1022 cm−1 ratio suggested that annealing resulted in an efficient packing of double helices. This work suggests that annealing, a safe and green method, produces modifications which can improve the properties of SNPs and therefore expand their applications in the fields of food, nutraceuticals, and other materials.

Self-nucleation of crystallization of polyamide 11 (PA 11) has been studied by thermo-optical microscopy. Spherulitically arranged lamellar crystals with a melting peak temperature of 187 °C formed via heterogeneous nucleation on slow cooling the equilibrium melt and subsequent reorganization on slow heating. As a function of the maximum temperature of the melt after their complete melting, subsequent non-isothermal crystallization accelerates, caused by presence of self-nuclei. The number of self-nuclei decreases with increasing temperature of the melt and approaches zero at a temperature about 13 K higher than the melting temperature of the initially present crystals. Crystallization of the melt containing self-seed leads to formation of a distinctly finer spherulitic morphology than melt-crystallization in absence of self-seed at identical conditions.

From the model of interstitial alloy AB with BCC structure and the condition of absolute stability for crystalline state we derive analytic expression for the temperature of absolute stability for crystalline state, the melting temperature and the equation of melting curve of this alloy by the way of applying the statistical moment method. The obtained results allow us to determine the melting temperature of alloy AB at zero pressure and under pressure. In limit cases, we obtain the melting theory of A main metal with BCC structure. The theoretical results are numerically applied for alloys FeH and FeC with using different potentials.

Latent heat thermal storage (LHTS) systems employing phase change materials (PCMs) offer several advantages compared to sensible heat storage units. However, they exhibit an inherent poor thermal performance owing to poor heat transfer, poor thermal conductivity of PCMs, and so on. Methods such as replacing single PCMs with multiple PCMs, addition of fins, micro/macro/nano-encapsulated composite PCMs and dispersion of high conductivity particles to PCMs have been suggested and studied in the past by different authors as a means for performance enhancement of LHTS systems. While extensive literature is available on the last three methods, studies on multiple PCMs are very limited. It is rather difficult at this stage to conclude on the benefits and merits/demerits of the method, given the limited data available in the open literature. Therefore, there is a need for consolidation and compilation of the existing literature to understand and assess the performance of LHTS units operating with multiple PCMs. An attempt is made in this paper to assess the performance of multiple PCM based thermal storage systems by carrying out a comprehensive review of available literature on the topic. Studies have evinced that single PCM units replaced with multiple PCMs offered superior performance with enhanced charging/discharging rates and better energy/exergy efficiencies. Also, past investigations reveal optimal melting temperatures of PCMs, optimal melting temperature difference between PCMs, optimal mass and so on to obtain an optimal performance of multiple PCM systems. Relevant published data were compared and discussed to understand the research trend over the years. Discussions were extended covering the challenges involved with multiple PCMs highlighting the scope for further research. An overall summary based on the survey has been presented for a concise understanding of key findings published in the open literature.

The high temperature properties of glass aggregates (i.e. thermal conductivity and melting temperature) play important roles on the performance of the glass concrete. It has been known that when glass aggregates are incorporated in concrete and the concrete is subjected to elevated temperatures, the melted glass surface could act as a binding material to mitigate the high temperature damages in the interfacial transition zone (ITZ) between the cement paste and the glass aggregates. In this study, the influence of the particle size of the glass aggregates on the properties of dry-mix glass concrete blocks after exposure to elevated temperatures of up to 800 °C was investigated. In order to avoid the influence of the pozzolanic reaction of the glass, glass particles of

We calculate the nearest-neighbour enthalpies and entropies at 5 salt concentrations of 18 RNA sequences, each for at least 9 different species concentrations, totalling 757 melting temperatures, using a melting temperature optimization method. These new parameters do not need to be salt-corrected and are shown to provide overall improved melting temperature predictions. They show a marked quadratic dependence with salt concentrations which are compensated to form linear Gibbs free energies. Two different parameter schemes were tested, with fixed or variable initial parameters. We have found that using variable initial parameters provides better predictive results than using salt correction factors and that the prediction uncertainty is considerably reduced for a validation set of independent sequences. An interpolation scheme is introduced to generate model parameters for arbitrary salt concentrations which performs better against a validation set than predictions using salt corrections.

In this paper, both a novel experiment and simulation model was presented to evaluate the performance of a solar still by applying a new shape-stabilized phase change material (SSPCM). The SSPCM was characterized with stable shape, high thermal conductivity and high solar absorption. Firstly, an experiment for solar still with SSPCM was carried out, and the SSPCM used in the experiment got thermal conductivity 1.50 W/m K and solar absorption around 0.94, which can replace the conventional metal absorber plate. Then, a comprehensive heat transfer model for the solar still was built to analyze the effect of melting temperature and thermal conductivity of the SSPCM on the performance of the solar still. The experimental results revealed that the daily productivity of solar still with SSPCM was 3.41 L/m2, 43.3% higher than that of conventional solar still without SSPCM. The simulation results showed that the daily productivity increased from 42% to 53% compared with that of conventional solar still when thermal conductivity of SSPCM increased from 0.2 W/m K to 4.0 W/m K. And increasing the melting temperature of SSPCM from 34 °C to 50 °C improved the percentage of enhancing productivity from 21.5% to 57.5%. Finally, the cost analysis was performed.

Bimodal grain structures are often produced in a metal by employing severe plastic deformation followed by low-homologous-temperature annealing (≤0.4Tm, where Tm is melting temperature). Here, a bimodal grain structure was achieved in a Co–20Cr–15W–10Ni–C superalloy via moderate cold rolling (strain ≈0.3) and ultrahigh-homologous-temperature annealing (≥0.8Tm). During annealing, carbide-assisted heterogeneous static-recrystallization played a key role in forming the bimodal grain structure. A 40% increase in combined strength and ductility was observed.

Accepted: 2018-12-01, 資料番号: SA1180327000

It is necessary to reduce the environmental load by reducing the energy consumption in the building sector. As one of the preferred methods, phase change materials (PCMs) are considered to be promising to store and discharge thermal energy. Recently, many studies of PCM applications in buildings by simulation tools have been conducted. However, there is not much research on glass curtain wall building (GCW) systems applied to PCM installation compared to conventional wall-based buildings (CWB). The objective of this paper is to investigate the optimization of PCM applied to GCW and to evaluate the building energy performance by EnergyPlus. A building model was selected from ASHRAE Standard 90.1–2013 prototype buildings, and Baltimore, Duluth, and Miami in ASHRAE climate classification was used as the input climate data. In this study, the experiment used Shape-stabilized PCM (SSPCM) with mixing ratio of n-octadecane and n-heptadecane (7:3), selected owing to the energy efficiency in the thermal comfort range based on ISO 13790. Considering PCM application to GCWs and CWBs, it is important to apply the optimized PCM considering the different approaches between GCWs and CWBs. In addition, a PCM melting temperature of 25 °C was the most suitable setting for the retrofit. PCM installation on a wall, a floor, and a ceiling with the same melting temperature was the most effective approach.

In this study, physicochemical, interfacial and emulsifying properties of Retama reatam and guar galactomannans were comparatively investigated. The results showed that Retama reatam galactomannan is mainly composed of total carbohydrates (95.52%) and lower protein contents (0.87%). The sugars identified were mannose (Man) and galactose (Gal), with a Man:Gal ratio of 1.85 compared to guar gum (1.83). The results of thermal properties indicated were transition temperature (Tg) and melting temperature (Tm) very similar to those of the guar gum. Moreover, results also revealed that there is no significant difference in terms of equilibrium interfacial tension of Retama reatam gum at 10 and 20°C. Moreover, preliminary tests show that stable oil-in-water nanoemulsions may be formulated using Retama reatam gum. Therefore, measurement of mean oil droplet diameter d after heating at 80°C, shows that stable nanoemulsions may be formulated using Retama reatam galactomannan. Further in vivo experiments confirmed that Retama reatam gum can reduce the glycemic index of starchy foods and inhibit the surge of postprandial blood glucose level.

In this work, we investigated the miscibility, crystallization behaviors and mechanical properties of the crystalline/crystalline poly(oxymethylene)/poly(butylene succinate) (POM/PBSU) blends. It was found that POM and PBSU are miscible in the melt state. The POM with a higher melting temperature (Tm) crystallizes first into banded spherulites and the crystals fill the whole melt space when cooling from the melt state. The low-Tm PBSU is simultaneously excluded into interfibrillar regions of the POM spherulitic frameworks. The crystallization of PBSU then takes place within the POM spherulites over a wide composition range. Moreover, we observed a significant increase in the crystallization rate of PBSU in the blends with PBSU content >50%. It is ascribed to the nucleating effect of POM crystals on PBSU crystallization. However, the growth kinetics of PBSU is depressed when PBSU content is