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The isobaric heat capacity of solid eutectic mixtures LiCl-KCl-CsCl, LiBr-CsBr and LiBr-KBr-CsBr was investigated from room temperature up to melting point. The molar heat capacity of all mixtures under study was found to be close to the additive sum of that of pure salts. The heat accumulated up to melting temperature is directly dependent on the melting point.

Understanding the self-assembly and hybridization properties of DNA oligonucleotides in confined spaces can help to improve their applications in biotechnology and nanotechnology. This study investigates the effects of spatial confinement in the pores of hydrogels on the thermal stability of DNA oligonucleotide structures. The preparation of oligonucleotides embedded in agarose gels was simple, whereas the preparation of oligonucleotides embedded in polyacrylamide gels was required to remove unpolymerized monomers. In the latter case, a method for rehydrating a washed dry gel with a buffer solution containing oligonucleotides was developed. Fluorescence measurements of oligonucleotides bearing fluorescent probes revealed no significant influence of the internal environment of the gel pores on the stability of DNA duplex, hairpin, and G-quadruplex structures. Moreover, the effects of poly(ethylene glycol) on the stability of DNA structures in the gels were similar to those in solutions. It is likely that the oligonucleotides are not strongly constrained in the gels and may be preferentially located in a water-rich environment in the gel matrix. The gel preparation was also applied to the assessment of the stability of DNA structures under the conditions of a reduced number of water molecules. The studies using hydrogels provide insights into the ability of self-assembly and hybridization of oligonucleotides in confined environments and under low-water-content conditions.

Background The use of Monoclonal Antibodies (MAbs) as therapeutics has been increasing over the past 30 years due to their high specificity and strong affinity toward the target. One of the major challenges toward their use as drugs is their low thermostability, which impacts both efficacy as well as manufacturing and delivery. Methods To aid the design of thermally more stable mutants, consensus sequence-based method has been widely used. These methods typically have a success rate of about 50% with maximum melting temperature increment ranging from 10 to 32°C. To improve the prediction performance, we have developed a new and fast MAbs specific method by adding a 3D structural layer to the consensus sequence method. This is done by analyzing the close-by residue pairs which are conserved in >800 MAbs’ 3D structures. Results Combining consensus sequence and structural residue pair covariance methods, we developed an in-house application for predicting human MAb thermostability to guide protein engineers to design stable molecules. Major advantage of this structural level assessment is in significantly reducing the false positives by almost half from the consensus sequence method alone. This application has shown success in designing MAb engineering panels in multiple biologics programs. Conclusions Our data science-based method shows impacts in Mab engineering.

With the explosion of data, DNA is considered as an ideal carrier for storage due to its high storage density. However, low-quality DNA sets hamper the widespread use of DNA storage. This work proposes a new method to design high-quality DNA storage sets. Firstly, random switch and double-weight offspring strategies are introduced in Double-strategy Black Widow Optimization Algorithm (DBWO). Experimental results of 26 benchmark functions show that the exploration and exploitation abilities of DBWO are greatly improved from previous work. Secondly, DBWO is applied in designing DNA storage sets, and compared with previous work, the lower bounds of storage sets are boosted by 9%-37%. Finally, to improve the poor stabilities of sequences, the End-constraint is proposed in designing DNA storage sets. By measuring the number of hairpin structures, melting temperature, and minimum free energy, it is evaluated that with our innovative constraint, DBWO can construct not only a larger number of storage sets, but also enhance physical and thermodynamic properties of DNA storage sets.

Experiments are performed to obtain the highest Tm and ΔHm values for poly(l-lactide)s. They also include comparison with literature data and of cyclic and linear species.

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.

The melting point is a fundamental property that is time-consuming to measure or compute, thus hindering high-throughput analyses of melting relations and phase diagrams over large sets of candidate compounds. To address this, we build a machine learning model, trained on a database of ∼10,000 compounds, that can predict the melting temperature in a fraction of a second. The model, made publicly available online, features graph neural network and residual neural network architectures. We demonstrate the model’s usefulness in diverse applications. For the purpose of materials design and discovery, we show that it can quickly discover novel multicomponent materials with high melting points. These predictions are confirmed by density functional theory calculations and experimentally validated. In an application to planetary science and geology, we employ the model to analyze the melting temperatures of ∼4,800 minerals to uncover correlations relevant to the study of mineral evolution.

Saccharides are still commonly isolated from biological feedstock by crystallization from aqueous solutions. Precise thermodynamic data on solubility are essential to optimize the downstream crystallization process. Solubility modeling, in turn, requires knowledge of melting properties. In the first part of this work, following our previous work on amino acids and peptides, D-α-glucose, D-β-fructose, D-sucrose, D-α-galactose, and D-α-xylose were investigated with Fast Scanning Calorimetry (FSC) in a wide scanning rate range (2000 K·s−1 to 10000 K·s−1). Using the experimental melting properties of saccharides from FSC allowed successfully modeling aqueous solubility for D-sucrose and D-α-galactose with the equation of state PC-SAFT. This provides cross-validation of the measurement methods to determine accurate experimental melting properties with FSC. Unexpectedly, the experimental FSC melting temperatures, extrapolated to zero scanning rates for thermal lag correction, were higher than results determined with DSC and available literature data. To clarify this inconsistency, FSC measurements towards low scanning rates from 10000 K·s−1 to 1 K·s−1 (D-α-glucose, D-β-fructose, D-sucrose) overlapping with the scanning rates of DSC and literature data were combined. At scanning rates below 1000 K·s−1, the melting properties followed a consistent non-linear trend, observed in both the FSC and the literature data. In order to understand the non-linear decrease of apparent melting temperatures with decreasing heating rate, the endothermic peaks were investigated in terms of isoconversional kinetics. The activation energies in the non-linear dependency region are in the range of 300, Food biophysics;Bd 17. 2022, H. 2, S.181-197

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.

Sustainable low melting temperature bicomponent polyester fibers that can be circularly recycled were developed. The potentially biobased poly(hexamethylene terephthalate) (PHT), acting as the low ...

Thermodynamic quantities in the coexistence of the liquid and the solid phases for Frost–Kalkwarf vapor- and sublimation-pressure equations are investigated at an isobaric process. Gibbs free energy changes in the gaseous and the liquid phases, ΔG GL, has been derived from the Frost–Kalkwarf vapor-pressure equation. Similarly, Gibbs free energy changes in the gaseous and the solid phases, ΔG GS, may be estimated by the Frost–Kalkwarf sublimation-pressure equations which are determined by data of sublimation pressures and temperatures for 24 substances. In coexistence between the liquid and the solid phases, Gibbs free energy changes in the liquid and the solid phases, ΔG LS, may be expressed as the difference of ΔG GL and ΔG GS. The melting temperatures and enthalpy changes of melting are evaluated by numerical calculations for 24 substances. The behaviors of H2O for the neighborhood at the melting and the boiling points are investigated. The Gibbs free energy indicates two polygonal lines. Entropy, volume and enthalpy jump from the solid to the liquid phase at the melting point and from the liquid to the gaseous phase at the boiling point. The heat capacity does not diverge to infinity but shows a finite discrepancy at the melting and the boiling points. This suggests that first-order phase transitions at the melting and the boiling points may occur.

Here, using ab initio calculations, we investigated the interaction between transition metals (M) and diamond C(111) surfaces. As a physical parameter describing the catalytic effect of a transition metal on diamond growth, we considered interfacial energy difference, ΔEint, between 1 × 1 and 2 × 1 models of M/C(111). The results showed that the transition-metal elements in the middle of the periodic table (groups 4–10) favor a 1 × 1 M/C(111) structure with diamond bulk-like interfaces, while the elements at the sides of the periodic table (groups 3, 11, and 12) favor a 2 × 1 M/C(111) structure with the 2 × 1 Pandey chain structure of C(111) underneath M. In addition, calculations of MC carbide formation for early transition metals (groups 3–6) showed that they have a tendency to form MC rather than M/C(111), which explains their low efficiency as catalysts for diamond growth. Further analysis suggests that ΔEint could serve as another parameter (catalytic descriptor) for describing catalytic diamond growth in addition to the conventional parameter of the melting temperature of M.

The importance of glacier sliding has motivated a rich literature describing the thermomechanical interactions between ice, liquid water and bed materials. Early recognition of the gradient in melting temperature across small bed obstacles led to focused studies of regelation. An appreciation for the limits on ice deformation rates downstream of larger obstacles highlighted a role for cavitation, which has subsequently gained prominence in descriptions of subglacial drainage. Here, we show that the changes in melting temperature that accompany changes in normal stress along a sliding ice interface near cavities and other macroscopic drainage elements cause appreciable supercooling and basal mass exchange. This provides the basis of a novel formation mechanism for widely observed laminated debris-rich basal ice layers.

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.

Deep eutectic solvents (DES) are eutectic mixtures that present a deviation from the ideal thermodynamic solid–liquid phase behavior, where a significant depression in the melting temperature occurs. If properly designed and chosen, DES may be liquid at room and the human body’s temperatures and display a biocompatible character, thus representing relevant options in the pharmaceutical field. Accordingly, DES have been studied as alternative solvents or in formulations of pharmaceuticals to improve their solubility and stability. Depending on the DES components, these mixtures might exhibit interesting biological activities compatible with several applications. The use of DES as functional agents or as novel liquid forms of active pharmaceutical ingredients (API-DES) with the goal of improving bioavailability, permeability and therapeutic efficacy of a given API stands as alternative strategies in the pharmaceutical field for drug delivery purposes.

The application of polybenzoxazine resin still remains a puzzling problem in processability due to the high melting temperature of benzoxazine. Here, a bio-based reactive diluent, 4-vinyl guaiacol ...

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.

We present a microfluidic approach that utilizes temperature-responsive and biocompatible palm oil as the shell material in microcapsules to simultaneously achieve hermetic sealing as well as on-demand temperature-triggered release of the encapsulated actives. Unlike common paraffin waxes (e.g., eicosane), microcapsule shells comprising palm oil do not form pores or cracks during freezing and provide a hermetic seal, a nearly perfect seal that separates the core containing the actives from the surrounding environment over a prolonged period of time. This allows effective isolation and protection of complex cargoes such as small molecules with high diffusivity, strong acids, and cosmetic actives including niacinamide. Moreover, the palm oil shell melts above the defined melting temperature, allowing the on-demand release of the encapsulated actives. Furthermore, palm oil is biocompatible, is edible, and leaves a minimal footprint when used in personal care and cosmetic products, offering new perspectives in the design of microcapsules for cosmetic applications.

A novel method, termed ladder-shape melting temperature isothermal amplification (LMTIA), was developed in this study. As a proof of concept, one pair of primers or two pairs of nested primers and a thermostable DNA polymerase were employed to amplify the internal transcribed spacer of Oryza sativa with the ladder-shape melting temperature curve. Our results demonstrated that the LMTIA assay with nested primers was 50-fold more sensitive than the LAMP assay with the same level of specificity. The LMTIA method has the potential to be used for the prevention and control of emerging epidemics caused by different types of pathogens.

The results of studies on lowering of the melting temperature of strontium aluminosilicate glass by introducing boron and phosphorus oxides into the batch are reported. The main physicochemical processes occurring in the batches on and heating and the sequence and temperature intervals in which they occur were determined.

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.

In view of the problem that the enrichment and migration law of the Ti element in the slag of vanadium-titanium magnetite during the melting process is not clear, the phase transformation is not clear and the enrichment effect is not obvious, the single factor experiment and orthogonal experiment are used to optimize the melting conditions of Ti enrichment. Through XRD, SEM and EDS analysis, the effects of melting temperature, alkalinity and carbon content on the Ti phase in the slag are studied, and the occurrence form and migration law of the Ti element in the slag system under different melting conditions are clarified. The results demonstrate that increasing the basicity and melting temperature is beneficial to the enrichment of Ti, but it is too high it will lead to the formation of pyroxene, diopside and magnesia-alumina spinel, affecting the enrichment of Ti. The increase in carbon content can make Ti occur in slag in the form of titanium oxides such as TiO, TiO2, Ti2O3 and Ti3O5, but excessive carbon content leads to the excessive reduction of Ti compounds to TiCN and TiC. After optimization, under the melting conditions of alkalinity 1.2, the melting temperature 1500 °C and carbon content 15%, the content of Ti in slag can reach 18.84%, and the recovery rate is 93.54%. By detecting the content of Fe and V in molten iron, the recovery rates are 99.86% and 95.64%, respectively.

Nickel phthalocyanine complex containing 4-(3,4-dicyanophenoxy)-3-methoxybenzoic acid group was synthesized and specified by way of FT-IR, NMR, UV/Vis procedures. The binding of PcNi complex to CT-DNA was examined via electronic absorption titration, emission titration, melting temperature, viscosity measurement, and agarose gel electrophoresis technics, respectively. The DNA interaction activity of PcNi against CT-DNA was studied by way of UV/Vi titrations, fluorescence spectra, farther by conducting melting point, viscosity procedures in the buffer of a pH 7.02. The obtained outcomes from these methods demonstrated that PcNi indicated substantial binding affinity to the DNA via intercalating by the binding constant of 1.31 x 106 m-1. Further, the interaction activity of the complex on CT-DNA was investigated by which the electrophoresis technique and this procedure indicated that PcNi complex exhibits strong binding affinity on the DNA.

Kendala yang sering dihadapi pada pembuatan produk spreads seperti shortening adalah sulitnya menghasilkan produk dengan titik leleh yang diharapkan. Interesterifikasi kimiawi dianggap lebih murah, sederhana, mudah dikontrol, suhu yang digunakan tidak terlampau tinggi sehingga memperkecil kemungkinan terbentuknya asam lemak trans. Tujuan penelitian ini adalah mengetahui karakteristik profil thermal dan melting point dari shortening melalui dua modifikasi lipid yang berbeda, blending (NIE) dan interesterifikasi kimiawi (CIE). Metode penelitian yang digunakan adalah rancangan acak lengkap (RAL) dengan 10 rasio perlakuan untuk mengetahui karakteristik leleh shortening menggunakan DSC (Differential Scanning Calorimetry). Hasil penelitian menunjukkan nilai melting point berada dalam kisaran leleh suhu (40-49°C). Berdasarkan Karakteristik Thermal rasio 90/5/5 (CIE 4) dan 80/10/10 (CIE 3) memiliki 3 dan 4 puncak titik leleh yang yang rendah. Berdasarkan data tersebut dapat disimpulkan bahwa melting point dan profil thermal interesterifikasi kimiawi lebih rendah jika dibandingkan blending, hal ini membuktikan bahwa intereterifikasi kimiawi mampu menciptakan lemak shortening baru dengan plastisitas tertentu dan memberikan karakteristik leleh sesuai dengan shortening komersial.

Compared to cow milk fat, camel milk fat presents a particular fatty acid composition and microstructure. For this reason, the production of camel milk butter following the same technology as for cow milk butter could be challenging. Hence, the main objective of this study was to investigate the effects of ripening temperature (5 °C, 12 °C, and 21 °C) and duration (0 h and 24 h) as well as the churning temperature (5 °C, 12 °C, and 21 °C) on the churning process of camel milk cream and camel milk butter. Results of the current study indicated that camel milk butter was only obtained when churned at 21 °C, regardless of ripening temperature. Analysis of solid fat content and polymorphism of camel cream before churning highlighted that the churning process for camel milk cream required the presence of β′1 and β-forms and a solid fat content lower than 27.5%. Furthermore, changing the ripening conditions had no significant influence on the water content, the solid fat content, and the polymorphism of camel milk butter. Finally, the findings of this study showed that the ripening and the churning conditions strongly affected the melting properties and the rheological behavior of camel milk butter. The lowest elastic modulus and the lowest TpMMF (melting temperature of medium fraction) were found for butter produced from cream ripened at 5 °C for 24 h.

Blending of poly(L-lactic acid)/poly(D-lactic acid) (PLLA/PDLA) leads to the formation of poly(lactide) stereocomplexation (PLA SC), which exhibits higher melting temperature and faster crystallization rate. The crystallization behavior of PLA homochiral crystallization (HC) under the existence of PLA SC was also widely investigated. During the variable processing, the SC with different morphologies would produce, and these SC could exert different influences on the subsequent formation of HC. However, the effects of SC developed in various conditions on the formation of HC are not compared yet and are also not clear until now, and which is important for the application of PLLA/PDLA blends. In this paper, the PDLAs with different molecular weights were blended with PLLA at a weight ratio of PLLA/PDLA 90/10, and the crystallization behaviors of PLLA HC from different conditions were investigated by differential scanning calorimetry (DSC). Results indicated that, incorporating a small amount of PDLA accelerated the formation of PLLA HC significantly regardless of the SC developed from the solution evaporation or the melt. The higher crystallization rate of HC was received in the PLLA/PDLA specimens with lower molecular weight of PDLA. For the specimens crystallized from the partially melting (most of SC developed during solution evaporation), the crystallization rate was higher than that corresponding specimens crystallized from the completely melting state (the SC were produced from the melt). This discrepancy would be due to variable SC morphologies produced during diverse processing.

Pathogenic variants (PVs) in CYP24A1 gene are associated with Idiopathic Infantile Hypercalcemia disease (IIH). The identification of CYP24A1 PVs can be a useful tool for the improvement of target therapeutic strategies. Aim of this study is to set up a rapid and inexpensive High Resolution Melting Analysis (HRMA)-based method for the simultaneous genotyping of two hot spot PVs in CYP24A1 gene, involved in IIH. A duplex-HRMA (dHRMA) was designed in order to detect simultaneously CYP24A1 c.428_430delAAG, p.(Glu143del) (rs777676129) and c.1186C > T, p.(Arg396Trp) (rs114368325), in peculiar cases addressed to our Laboratory. dHRMA was able to identify clearly and simultaneously both hot spot CYP24A1 PVs evaluating melting curve shape and melting temperature (Tm). This is the first dHRMA approach to rapidly screen the two most frequent CYP24A1 PVs in peculiar case, providing useful information for diagnosis and patient management in IIH disease.

Prime editing (PE) applications are limited by low editing efficiency. Here we show that designing prime binding sites with a melting temperature of 30 °C leads to optimal performance in rice and that using two prime editing guide (peg) RNAs in trans encoding the same edits substantially enhances PE efficiency. Together, these approaches boost PE efficiency from 2.9-fold to 17.4-fold. Optimal pegRNAs or pegRNA pairs can be designed with our web application, PlantPegDesigner. Improved guide RNAs enhance the efficiency of prime editing.

An alternative approach to calculating the critical nucleus size and the nucleus formation energy has been developed. A significant difference between this method and the generally accepted so-called classical method, according to which a nucleation center begins to form at the melting temperature, is noted. The results are illustrated by the dependences of the nucleus size and the nucleus formation energy on the supercooling and by the Gibbs energy plotted as a function of the nucleus size in both the classical and the proposed versions.

We investigate the melting ranges of the base Zr–Si mixture (eutectic composition) depending on the content of the heterophase powder component in the ZrB2–ZrSi2–MoSi2 and the HfB2–HfSi2–MoSi2 systems in the amount of 30–90 wt % obtained by self-propagating high-temperature synthesis (SHS). The range of the melting point of the Zr–Si mixture was 1420–1440°C; addition of the ZrB2–ZrSi2–MoSi2 SHS powders resulted in an increase of the melting onset temperature Tm0 to 1460–1560°C and in the complete melting temperature Tmelt to 1480–1670°C. Addition of the HfB2–HfSi2–MoSi2 powders influenced only slightly the Tm0 value (1390–1430°C), but resulted in the increase in Tmelt to 1510–1550°C. The X-ray phase analysis shows that the remelted samples contain the following phases: ZrB2/HfB2, ZrSi2/HfSi2, MoSi2, and Si; here, the number of phases was directly proportional to the SHS powder content in the Zr–Si mixture. The ingots are characterized by a homogeneous structure consisting of the silicon matrix and ZrSi2/HfSi2 and MoSi2 grains, with inclusions of ZrB2/HfB2.

We investigated the relationship of the vacancy formation energy with kinematic viscosity and self-diffusion coefficient in liquid metals at the melting temperature. Formulas are obtained that relate experimental values of the vacancy formation energy, kinematic viscosity, and self-diffusion coefficient to the atomic size and mass, the melting and Debye temperatures. The viscosity and self-diffusion parameters are introduced. The ratio of these parameters to vacancy formation energy is equal to dimensionless constants. It is shown that the formulas for viscosity and self-diffusion differ only in dimensionless constants; the values of these constants are calculated. Linear regression analysis was carried out and formulas with the highest adjusted coefficient of determination were identified. The calculated values of the self-diffusion coefficient for a large number of liquid metals are presented.

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.

In gas-phase polyolefin processes, it is important to evaluate the melting temperature of particles since exceeding this temperature may cause particle sticking and aggregation. In this work, a mod...

This paper analyses the thermal behaviour of six EVA copolymers supplied by REPSOL Company. In relation to crystallization and melting temperatures, both of them decrease when the vinyl acetate percentage increases, in agreement with the fact that polyethylene is a semi-crystalline material, whereas polyvinylacetate is an amorphous polymer. Actually, when the vinyl acetate percentage reaches 30%, the copolymer is practically amorphous. The non-isothermal crystallization was modelled with the modified Avrami model that showed, with the exception of EVA-460 (the material with higher vinyl acetate percentage), the presence of a secondary crystallization due to spherulite impingement in the later stage of the non-isothermal crystallization. The TG analysis indicated two weight loss stages, the first one due to acetic acid loss and the second one due to fragments of polymer backbone, which appear as two separate peaks in the DTG plots. Finally, due to the linear dependence of melting and crystallization temperatures and of the minimum value of DTG peaks on vinyl acetate percentage, it can be concluded that both TG and DSC techniques can be employed to determine the vinyl acetate percentage of a certain copolymer.

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.

The paper provides experimental data on the synthesis and study of the superconducting properties of potassium and rubidium heterofullerides modified by Wood’s alloy — Sn, Pb, Bi, Cd (hereinafter W) with a melting temperature Tm = 61.5 °C or Y alloy — Bi, Sn, Pb, In, Cd, Tl with Tm = 41.5 °C. The synthesis of heterofullerides was carried out by the interaction of fullerides of the composition K2C60 and Rb2C60, which do not have superconducting properties, with one of the alloys W or Y in an organic solvent — toluene at 100–110 °C. The samples obtained in this case showed superconducting properties with Tc = 8 K for K2YC60 and Rb2WC60 and 16 K for K2WC60.

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 response to the environmental concerns posed by synthetic non-degradable polymeric packaging materials, efforts are being devoted to developing bio-degradable packaging materials that are based on green and sustainable resources. As a class of green materials, poly (lactic acid) (PLA) has received extensive attention. In this work, PLA was filled with guinea-corn (Sorghum bicolor) husk particulates (GHP) to produce biocomposites, and thereafter analysed by differential scanning calorimetry (DSC). The plain PLA was plasticized by Biomax strong (PLABM). Formulations of the composites were produced with untreated GHP and those treated with sodium hydroxide, 3-aminopropyltriethoxysilane and a combination of both treatments varying the filler composition from 10 to 40 wt% at 10 wt% interval. This was achieved by melt-mixing using extrusion and pelletizing followed by injection moulding. The composites produced were subjected to DSC thermal analysis. Result of the analysis reveals that the glass transition temperature (Tg) of PLABM was 60 °C and its melting temperature (Tm) was 150 °C. The degree of crystallinity was found to be 12.66%. It was also observed that percentage GHP loading of the composite does not substantially affect its processing temperature. The composites produced were bio-degradable and suitable for short-term use or indoor application.