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The clustered regularly interspaced short palindromic repeats (CRISPR)-associated (Cas) system is a technology that is used to perform site-specific gene disruption, repair, and the modification of genomic DNA via DNA repair mechanisms, and is expected to be a fundamental therapeutic strategy for the treatment of infectious diseases and genetic disorders. For clinical applications, the non-viral vector-based delivery of the CRISPR/Cas ribonucleoprotein (RNP) is important, but the poor efficiency of delivery and the lack of a practical method for its manufacture remains as an issue. We report herein on the development of a lipid nanoparticle (LNP)-based Cas RNP delivery system based on optimally designed single stranded oligonucleotides (ssODNs) that allow efficient in vivo genome editing. The formation of sequence-specific RNP-ssODN complexes was found to be important for the functional delivery of RNP. Furthermore, the melting temperature (Tm) between sgRNA and ssODN had a significant effect on in vivo gene knockout efficiency. An ssODN with a high Tm resulted in limited knockout (KO) activity while that at near room temperature showed the highest KO activity, indicating the importance of the cytosolic release of RNPs. Two consecutive intravenous injections of the Tm optimized formulation achieved approximately 70% and 80% transthyretin KO at the DNA and protein level, respectively, without any obvious toxicity. These findings represent a significant contribution to the development of safe in vivo CRISPR/Cas RNP delivery technology and its practical application in genome editing therapies. [Display omitted] [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The solar water heater can be integrated into future residential buildings as the main energy source, which will subsequently reduce the energy cost of water heating. An original configuration for an efficient Domestic Hot Water (DHW) storage tank is developed and experimentally evaluated under Saharan climate. This novel DHW configuration includes a hybrid (solar and electric) energy system with a flat plate solar collector coupled with an electric heater. Additionally, a phase change material (PCM) mixture that is composed of paraffin wax and animal fat with a melting temperature between 35.58 °C and 62.58 °C and latent heat between 180 and 210 kJ/kg is integrated into this novel tank configuration. The experimental results indicated that hot water production by using latent heat storage could be economically attractive. By evaluating the cost of water heating expressed in Algerian dinar per liter (DZD/L), it was found that one liter of hot water may cost around 0.1362 DZD/L (i.e., 0.00096 USD/L) compared to 0.4431 DZD/L for the conventional water heater, an average energy cost savings of 69.26%. On a yearly basis, the average energy cost savings may reach up to 80.25% if optimal tilt for the solar collector is adopted on a monthly basis. The flat plate collector may be vulnerable to convective heat transfer; therefore, other solar collectors, such as vacuum tube collectors, may provide enhanced energy performance. [ABSTRACT FROM AUTHOR]

A scalable continuous manufacturing method to produce stereocomplex PLA was developed and optimized by melt-blending a 1:1 blend of high molecular weight poly(L-lactide) (PLLA) and high molecular weight poly(D-lactide) (PDLA) in a co-rotating twin-screw extruder. Thermal characteristics of stereocomplex formation were characterized via DSC to identify the optimal temperature profile and time for processing stereocomplex PLA. At the proper temperature window, high stereocomplex formation is achieved as the twin-screw extruder allows for alignment of the chains; this is due to stretching of the polymer chains in the extruder. The extruder processing conditions were optimized and used to produce >95% of stereocomplex PLA conversion (melting peak temperature Tpm = 240 °C). ATR-FTIR depicts the formation of stereocomplex crystallites based on the absorption band at 908 cm−1 (β helix). The only peaks observed for stereocomplex PLA's WAXD profile were at 2θ values of 12, 21, and 24°, verifying >99% of stereocomplex formation. The total crystallinity of stereocomplex PLA ranges from 56 to 64%. A significant improvement in the tensile behavior was observed in comparison to the homopolymers, resulting in a polymer of high strength and toughness. These results lead us to propose stereocomplex PLA as a potential additive/fiber that can reinforce the material properties of neat PLA. [ABSTRACT FROM AUTHOR]

This work investigates the high temperature behavior of six different quartz types A, B, C, D, F and G during heating to elevated temperatures. These quartz types contain different amounts of impurities, from 1% to 0.1%, and have earlier shown different degree of disintegration during heating. Melting experiments to 1750 °C have been performed to find softening and melting temperatures, and it is found that there are significant variations between the different quartz types. A higher content of impurities lowers the softening and melting temperature. The quartz surface has also been studied during heating to 1600 °C in a high temperature confocal microscope. From this, it is found that disintegration mainly happens at two temperature intervals, ~300–600 °C and ~1300–1600 °C, and is mostly due to volume changes in either the SiO2 matrix or the impurity areas. The cracks occur from impurity areas, expanding grain boundaries, damaged or uneven SiO2 surface and in some cases from the cavities from the escaped fluid inclusions. [ABSTRACT FROM AUTHOR]

A study of experimental data reveals that the bulk modulus of chalcogenides and pnictides based chalcopyrites (AIIBIVC2V and AIBIIIC2VI) can be explained by a simple scaling rule that rely only on the crystal ionicity, ionic charge product, and the melting temperature. PVV theory of crystal ionicity, temperature dependence of elasticity and product of ionic charge theory are taken into account for the study. Based on this result, a simple microhardnessbulk modulus relation is applied to evaluate the microhardness of the complex compounds; which correspond well with the experimental data and other published results. The proposed findings support in the modeling of emerging semiconductor materials and even understanding of their mechanical properties for optoelectronics, photovoltaic, electromagnetic (EM) screening, and spintronic applications. PACS: 62.20.-x; 62.20.Qp. [ABSTRACT FROM AUTHOR]

To improve the yield of titanium alloy, a certain amount of TiO2 can be added to the refining slag system of Ti-bearing steel grades. With the aim of understanding the effect of TiO2 addition on the melting behaviors of CaO-SiO2-30%Al2O3-5%MgO refining slags, the melting points of the slags and the phases in the slags are herein studied at different temperatures in the laboratory. It is found that with the increase in TiO2 content (0~10%) in slag, the melting point of the slags drops first, and then rises. The effect of slag basicity (R = w(CaO)/w(SiO2), 2~10) shows a similar tendency. The TiO2 content and slag basicity evidently affect the precipitated phases in the slags at a lower temperature (e.g., 1310 °C). With the increase in basicity, the liquid areal fraction increases first, and then decreases. Moreover, the CaO-TiOx-Al2O3 phase (CTA) and its TiOx content show a declining trend at 1310 °C. When R = 10, large amounts of solid calcium aluminates are precipitated. With TiO2 addition in the slags, the TiOx contents in both liquid and CTA phases increase. Excessive TiO2 addition (e.g., 10%) leads to the large precipitation of CTA, as well. To improve the melting properties of the slag and the yield of Ti alloys during the refinement of Ti-bearing steel grades, a small TiO2 addition (e.g., 5%) may be considered. [ABSTRACT FROM AUTHOR]

The morphology and structure of polylactide film samples obtained from a melt and from a solution in chloroform are studied. The crystallization process of polylactide takes place under nonisothermal conditions. It is determined that the melting and crystallization points of the polylactide sample obtained from the solution are, respectively, 2 and 4°C lower than the sample obtained from the melt. Using optical polarization microscopy, it is shown that the sample obtained from the solution has a spherulite structure, while spherulites are not detected in the polylactide sample obtained from the melt. The X-ray diffraction patterns of the polylactide samples crystallized from the solution and melt are different. Well-defined reflexes characteristic of the crystalline modification of the α-form are recorded on the diffractogram of the sample obtained from the solution. The pressed polylactide sample has an initially X-ray amorphous structure, which partially transforms into a crystalline structure during annealing for 60 min at 90°C. X-ray diffraction analysis revealed differences in the degree of crystallinity over the thickness of the polylactide sample obtained from the solution. [ABSTRACT FROM AUTHOR]

Inotodiol, an oxysterol found only in Chaga mushroom, has received attention from the pharmaceutical industry due to its strong antioxidant and anti-allergic activities. However, the production of inotodiol is still challenging, and its fundamental properties have yet to be investigated. This study aims to develop an efficient method to produce high-purity inotodiol from Chaga mushroom. Then, pure inotodiol was used to assess its physicochemical properties and biological activities. By optimizing the solvent used for extraction and purification, a new method to produce inotodiol was developed with high purity (>97%) and purification yield (33.6%). Inotodiol exhibited a melting point (192.06 °C) much higher than lanosterol and cholesterol. However, the solubility of inotodiol in organic solvents was notably lower than those of the other two sterols. The difference in the hydroxyl group at C-22 of inotodiol has shown the distinctive physicochemical properties of inotodiol compared with cholesterol and lanosterol. Based on those findings, a nonionic surfactant-based delivery system for inotodiol was developed to improve its bioavailability. The inotodiol microemulsion prepared with 1–2% Tween-80 exhibited homogenous droplets with an acceptable diameter (354 to 217 nm) and encapsulation efficiency (85.6–86.9%). The pharmacokinetic analysis of inotodiol microemulsion in oral administration of 4.5 mg/kg exhibited AUC0–24h = 341.81 (ng·h/mL), and Cmax = 88.05 (ng/mL). Notably, when the dose increased from 4.5 to 8.0 mg/kg, the bioavailability of inotodiol decreased from 41.32% to 33.28%. In a mouse model of sepsis, the serum level of interleukin-6 significantly decreased, and the rectal temperature of mice was recovered in the inotodiol emulsion group, indicating that inotodiol microemulsion is an effective oral delivery method. These results could provide valuable information for applying inotodiol in functional food, cosmetic, and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

Based on the analysis of phase diagrams of carbide-forming systems M–C (M = Ti, Zr, Hf), an empirical relationship is proposed between the elastic stiffness constants c ij of nonstoichiometric cubic carbides of titanium, zirconium and hafnium and their melting temperature. The dependences of the melting temperatures of nonstoichiometric cubic carbides TiC y , ZrC y and HfC y on their composition in homogeneity regions are calculated using the elastic stiffness constants c 11 (y) and c 44 (y) of these carbides. The calculated maximum melting temperatures are observed for carbides ∼TiC 0.80 , ∼ZrC 0.82 and ∼ HfC 0.94 – 0.95 and are equal to 3345, 3708 and 4192 K, respectively. There is a qualitative correlation between the concentration dependences of the melting temperatures T m (y) of TiC y , ZrC y and HfC y carbides and the anisotropy of the elastic properties of these carbides. [Display omitted] • Method of calculation of melting temperatures of TiC y , ZrC y and HfC y is proposed. • Carbides melting temperature T m is empirical function of their elastic constants. • Melting temperature dependences T m (y) on carbides MC y composition have a maximum. • Maximal melting temperatures are observed for TiC 0.80 , ZrC 0.82 , HfC 0.94 carbides. • There is qualitative correlation between T m (y) and the anisotropy of MC y carbides. [ABSTRACT FROM AUTHOR]

The epigenetics of methylated and unmethylated DCR1 and DCR2 (decoy receptors 1 and 2) are genes encoding membrane receptors that can bind to TRAIL causing TRAIL inhibition in the apoptotic pathway. Epigenetic detection of DCR1 and DCR2 was developed as a biomarker of breast cancer. One of the detection methods is using PCR. The most important step in the PCR process is the determination of the annealing temperature. This research performs Tm analysis using the insilico program from Neb, insilico, Thermofisher, and Promega and in vitro optimization. Methylated DCR1 can be amplified at annealing temperatures of 51.4°C, 52.4°C, 53.6°C, 54.7°C measuring about 600bp according to Tm analysis of insilico and promega. DCR1 could also be amplified at annealing temperatures of 50,1, 49, and 48.8 but the primers were also amplified at non-specific sites. Methylated DCR2 could be amplified at annealing temperatures of 48.8°C, 49°C and 50.1°C and a specific size of about 500 bp according to the Tm analysis of promega. Unmethylated DCR1 and DCR2 genes could not be amplified at the annealing temperature which were analyzed using Neb, insilico, promega, and thermofisher.

Melting temperature (T m) is a crucial physical property of solids and plays an important role in the characterization of materials. Therefore, the capacity to predict T m is a relevant issue for solid state sciences. This investigation aims i) to provide a theoretical basis for the link between catastrophe theory and thermodynamic instability; ii) to estimate T m through the notion of "degenerate critical temperature" (T d), related to (P d , V d , T d), where K T → 0 and the Gibbs function shows a non -Morse behaviour; iii) to compare predictions of (P m , T m) with observations for three crystalline pure substances that undergo congruent melting and exhibit different bonding and stability ranges: NaCl (halite), SiO 2,st (stishovite), and MgSiO 3 (perovskite). The P - T locus of K T = 0 associated with melting is identified using the maximum values of T d and Δ H /Δ V at a given pressure. We observed an average absolute discrepancy ranging between 0.2 % (halite) and 5.8 % (stishovite), and an agreement between theoretical and experimental T (P) melting -points from better than 1 to approximately 14 %. [ABSTRACT FROM AUTHOR]

• Heat capacities of compounds in the range (5–370) K were measured for the first time. • Thermal stability and melting parameters of compounds were determined using DSC+TGA. • Thermodynamic properties in the range of (0 – T m) K were calculated. • Thermodynamic properties of compounds explained with their structure. In this paper, we present the results of comprehensive thermodynamic study of some functionally substituted triazoles such as 1-benzyl-4-phenyl-1 H -1,2,3-triazole, 1-benzyl-4-(m -tolyl)-1 H -1,2,3-triazole and 1-benzyl-4-(4‑ tert -butylphenyl)-1 H -1,2,3-triazole. The temperature dependences of heat capacities of 1-benzyl-4-(m -tolyl)-1 H -1,2,3-triazole and 1-benzyl-4-(4‑ tert -butylphenyl)-1 H -1,2,3-triazole were measured in a wide temperature range of ∼(5 – 370) K using the adiabatic calorimetry. Those of 1-benzyl-4-phenyl-1 H -1,2,3-triazole were determined at the range of ∼(5 – 80) K, supplementing the previous measurements at the more elevated temperatures. The melting parameters and thermal stability (melting temperature, enthalpy of fusion, temperature of thermal destruction) of the compounds were determined using the differential scanning calorimetry. Also, the standard thermodynamic functions (absolute entropies, reduced enthalpies and Gibbs energies) were calculated in the temperature range of (0 – T m) K. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • The size dependence of melting temperature T m (D) of semiconductor nanocrystals is modeled. • T m (D) is decreased following the reduction of size D of semiconductor nanocrystals. • The ratio of solid/liquid interface energy to surface stress dominate the variation tendency of T m (D). Exploring the thermal stability of semiconductor crystals at the nanoscale is of great significance for the design, fabrication, and application of modern quantum devices. In this paper, we propose a thermodynamic model to predict the melting temperature of semiconductor nanocrystals, which is in good agreement with the experimental results of Si, Bi, CdS, and CdSe. In addition, when the size decreases, the drop of melting temperature curves tends to be synchronized with the size-dependent solid/liquid interface energy and surface stress ratio γ sl (D)/ f (D), which reveals the physical origin of the decrease in the melting temperature of the semiconductor nanocrystals. [ABSTRACT FROM AUTHOR]

[Display omitted] • A DP model with electronic entropy is developed for iron under core conditions. • The DP model accurately describes Gibbs free energy consistent with ab initio data. • DP, ab initio and experimental data reach consensus on iron's melting point at ICB. Constraining the melting temperature of iron under Earth's inner core conditions is crucial for understanding core dynamics and planetary evolution. Here, we develop a deep potential (DP) model for iron that explicitly incorporates electronic entropy contributions governing thermodynamics under Earth's core conditions. Extensive benchmarking demonstrates the DP's high fidelity across relevant iron phases and extreme pressure and temperature conditions. Through thermodynamic integration and direct solid–liquid coexistence simulations, the DP predicts melting temperatures for iron at the inner core boundary, consistent with previous ab initio results. This resolves the previous discrepancy of iron's melting temperature at ICB between the DP model and ab initio calculation and suggests the crucial contribution of electronic entropy. Our work provides insights into machine learning melting behavior of iron under core conditions and provides the basis for future development of binary or ternary DP models for iron and other elements in the core. [ABSTRACT FROM AUTHOR]

Ag-based brazing filler metals are preferred in many industries, but the high price of Ag restricts their wider application. Therefore, developing novel low-Ag brazing filler metals has aroused extensive interest. In this study, the effects of the In and Ga elements on the melting behavior and spreading property of Ag10CuZnSn filler metal and the microstructure and strength of the brazed joints were investigated. The results show that both In and Ga can significantly decrease the solidus and liquidus temperatures of the filler metal. The In element can dissolve into the liquid filler metal and the Ga element can decrease the surface tension of the melted filler metal, which, in turn, improves the spreading area. The In element prefers to dissolve into the Ag-rich phase, and the Ga element prefers to dissolve into the Cu-rich phase; both improve the strength of the filler metal through solid-solution strengthening. The shear strength of the 304 stainless-steel brazed joint reached a peak value of 396 MPa when the Ag10CuZnSn-1.5In-2Ga (wt%) filler metal was used. However, the excessive addition of In and Ga forms brittle intermetallic compounds (IMCs) in the brazing seam, which decreases the strength of the brazed joint.

Introduction. The demand for halogen-free fire-resistant compositions for the manufacture of fire-retardant wires and cables is constantly growing. Problem. Therefore, the creation and further processing of these materials is an urgent problem. Goal. The aim of the article is to study the effect of the doping additive on the thermophysical and rheological properties of halogen-free compositions for power cables with voltage 1 kV with the determination of both the temperatures of phase and structural transformations of polymer compositions. Methodology. Experiments investigating the phase transformations were carried out with the help device of thermogravimetric analysis and differential scanning calorimetry TGA/DSC 1/1100 SF of METTLER TOLEDO company. Rheological studies of polymeric materials were conducted by using the method of capillary viscosimetry in the device IIRT–AM. Results. The influence of the doping additive on the formation of the supramolecular structure of the filled polymer compositions for cable products was determined, that resulted in the temperature increase of the decomposition beginning by 11 °С and the end of decomposition by 7 °С. Originality. The effect of a doping additive on reducing the effective melt viscosity of a polymer composition from 6·104 to 1·104 Pa·s with increasing shear rate has been shown for the first time. The shear rate of the polymer composition containing the doping additive increases from 0.5 to 20 s–1 with increasing shear stress. Practical value. The research results provide an opportunity to reasonably approach the development of effective technological processes for the manufacture of the insulation and sheaths of power cables from halogen-free polymer compositions.

The purpose of the work was to experimentally substantiate the composition and study the stability of extemporal suppositories with Echinacea, intended for use in complex therapy and prevention of genitourinary diseases. Materials and methods. The object of the study was samples of suppositories made by pouring using liquid Echinacea extract as an active pharmaceutical ingredient. Cocoa butter, Witepsol H15 and Witepsol W35 were used as suppository bases. The study was carried out using modern physicochemical, pharmaco-technological and microbiological methods. Results. On the basis of the carried out physicochemical and pharmaco-technological studies, it was found that in the manufacture of suppositories using liquid Echinacea extract, Cocoa butter or Witepsol can be used as a suppository bases. The main indicators of the quality of suppository samples were also studied: organoleptic characteristics, average weight, melting point, time of complete deformation, microbiological purity, meeting the requirements of the State Pharmacopoeia. Conclusions. As a result of the carried out physicochemical, pharmaco-technological and microbiological studies, a suppository base was selected for the creation of extemporal suppositories for the treatment and prevention of genitourinary diseases, the main quality indicators were established that meet the requirements of the State Pharmacopoeia of Ukraine, and the shelf life of the suppositories is 10 days.

Abstract There has been a long debate on the stable phase of iron under the Earth’s inner core conditions. Because of the solid‐liquid coexistence at the inner core boundary, the thermodynamic stability of solid phases directly relates to their melting temperatures, which remains considerable uncertainty. In the present study, we utilized a semi‐empirical potential fitted to high‐temperature ab initio data to perform a thermodynamic integration from classical systems described by this potential to ab initio systems. This method provides a smooth path for thermodynamic integration and significantly reduces the uncertainty caused by the finite‐size effect. Our results suggest the hcp phase is the stable phase of pure iron under the inner core conditions, while the free energy difference between the hcp and bcc phases is tiny, on the order of 10 s meV/atom near the melting temperature.

Blast furnace slag and steelmaking slag, as the main accessory products of iron and steel smelting, are piled up in large quantities due to their huge output, high treatment difficulty and low comprehensive utilization rate, which has a serious impact on the land and environment. In order to improve the comprehensive utilization of steelmaking slag, low basicity blast furnace slag was added to the existing steel slag for quenching and tempering. The influence of basicity on the chemical composition and phase precipitation of mixed slag was analyzed. In the research process, the phase composition and morphology of blast furnace slag and steel slag of Baotou Steel were analyzed using FactSage7.1 thermodynamic calculation software, ZEISS high-resolution scanning electron microscope (SEM), modern fast high-resolution Bruker energy dispersive spectrometer and AMICS-Mining automatic mineral analysis software. The results show that the mineral phase composition of blast furnace slag is mainly calcium aluminum yellow feldspar and that of steelmaking slag is mainly dicalcium silicate(C2S), magnesium-iron phase solid solution, rose pyroxene and calcium iron aluminate. When the basicity of the mixed slag is 2.0, it can effectively inhibit the formation of non-cementitious mineral anorthite and promote the formation of better cementitious mineral C2S. At the same time, it is found that the melting temperature of mixed slag decreases with the increase in Al2O3 content.

[Display omitted] The specific effects of salts (strong electrolytes) on biomolecular properties have been investigated for more than a century. By contrast, the specific role of pH buffers (weak electrolytes and their salts) has usually been ignored. Here, specific buffer effects on DNA thermal stability were evaluated by measuring the melting curve of calf thymus DNA through UV–vis spectroscopy. The study was carried out using phosphate, Tris, citrate and cacodylate buffers at fixed pH 7.4 at concentrations varying systematically in the range 1–600 mM. DNA stability increases with buffer concentration and is influenced specifically by buffer type. To interpret empirical data, a theoretical model was applied with parameters quantifying the impact of buffer on the DNA backbone charge. Comparing the buffer effects via buffer ionic strength rather than buffer concentration, we find that the buffers stabilize DNA in the order Tris > cacodylate > phosphate > citrate. [ABSTRACT FROM AUTHOR]

The p53 protein is a transcription factor that preserves the integrity of the genome. The TP53 gene has inactivating mutations in about 50% of all human cancers. Some missense mutations lead to decreased thermal stability in the p53 protein, its unfolding and aggregation under physiological conditions. A general understanding of the impact of point mutations on the stability and conformation of mutant p53 is essential for the design and development of small molecules that target specific p53 mutations. In this work, we determined the thermostability properties of some of the most common mutant forms of the p53 protein—p53(R273H), p53(R248Q), p53(R248W) and p53(Y220C)—that are often considered as attractive therapeutic targets. The results showed that these missense mutations lead to destabilization of the p53 protein and a decrease in its melting temperature. [ABSTRACT FROM AUTHOR]

High-performance hybrid polymer blends can be prepared by blending different types of polymers to improve their properties. However, most polymer blends exhibit phase separation after blending. In this study, polymethylmethacrylate/polyethylene glycol (PMMA/PEG) polymer blends (70/30 and 30/70 w/w) were prepared by solution casting with and without ZnO nanoparticles (NPs) loading. The effect of loading ZnO nanoparticles on blend morphology, UV blocking, glass transition, melting, and crystallization were investigated. Without loading ZnO NP, the PMMA/PEG blends showed phase separation, especially the PEG-rich blend. Loading PMMA/PEG blend with ZnO NPs increased the miscibility of the blend and most of the ZnO NPs dispersed in the PEG phase. The interaction of the ZnO NPs with the blend polymers slightly decreased the intensity of infrared absorption of the functional groups. The UV-blocking properties of the blends increased by 15% and 20%, and the band gap energy values were 4.1 eV and 3.8 eV for the blends loaded with ZnO NPs with a PMMA/PEG ratio of 70/30 and 30/70, respectively. In addition, the glass transition temperature (Tg) increased by 14 °C, the crystallinity rate increased by 15%, the melting (Tm) and crystallization(Tc) temperatures increased by 2 °C and 14 °C, respectively, and the thermal stability increased by 25 °C compared to the PMMA/PEG blends without ZnO NP loading. [ABSTRACT FROM AUTHOR]

The effect of Na2O on the viscosity, structure, and crystallization behavior of CaF2–CaO–Al2O3–MgO–TiO2 slag was studied using the rotating cylinder method, differential scanning calorimetry, Fourier transform infrared spectroscopy, and X-ray diffraction analyses. The analyses demonstrated that with increasing Na2O content, the viscosity and melting temperature of the slag decreased; however, the crystallization temperature increased. Na2O acted as a network modifier to decrease the degree of polymerization in the titanoaluminate structure and consequently increased the mobility of ions in the slag structure. The network structures in the [AlOnF4 – n]-tetrahedral complexes and [AlO4]-tetrahedra are depolymerized with the addition of Na2O; however, the depolymerization had a minimal effect on the Ti–O stretching vibration. During the continuous cooling process of the slag without Na2O, the crystalline phases of 11CaO·7Al2O3·CaF2 were dominant, followed by CaF2 and CaTiO3. In addition to the first three phases, a new precipitated phase of NaAlO2 was observed in the slag when Na2O was added, and the sequence of crystallized precipitation during the continuous cooling process was 11CaO·7Al2O3·CaF2, CaF2, CaTiO3, and NaAlO2. The effective activation energy of 11CaO·7Al2O3·CaF2 increased with increase in Na2O content (0–3.9 wt %) and reached a maximum; however, a further increase in Na2O content (6.6 wt %) decreased the effective activation energy of 11CaO·7Al2O3·CaF2. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

In this study, borosilicate glass-ceramic waste forms containing pyrochlore crystalline phase (PBGC) were prepared by one-step heat-treated method. The effect of Nd 2 O 3 dosages and melting temperatures on the crystalline phases and microstructure of PBGC were studied by using X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Product Consistency Test (PCT) was used to investigate the aqueous durability of PBGC. The 14 wt% Nd 2 O 3 doping in PBGC contributes to the formation of pyrochlore (Ca,Na)(Nb,Ti) 2 Nd 0.67 O 6 F. The optimal supercooling region of the glass-ceramic is from the melting temperature of 1325 °C to the initial cooling temperature of 1000 °C. The prepared glass-ceramic has a stable pyrochlore crystalline structure. In addition, the normalized leaching rates of major elements in PBGC are comparable to those of standard reference glass for immobilization of high-level wastes (HLWs). The results of this study provide useful guidance on the immobilization of certain HLWs in the industry using glass-ceramic materials. [ABSTRACT FROM AUTHOR]

The concentration dependences of melting temperature Ts.s. s, Debye temperature ss.. Θ s.s.D and lattice parameter as.s. for massive high-entropy alloys based on Fe, Ni, Co, Cu and Al were analyzed within the concept of additivity of physical values of high-entropy alloys. 4- and 5-component alloys were considered in the form of single-phase solid solutions. It was established that Ts.s. s can vary within 150 K, that is,Ts.s. s insensitive to changes in the concentration of individual atoms. It is even less sensitive to concentration Θ s.s.D since the maximum value is ss. . ∆Θs.s.D ≅80 K. The lattice parameters change in accordance with Vegard's rule. [ABSTRACT FROM AUTHOR]

The design of stable formulations remains a major challenge for protein therapeutics, particularly the need to minimize aggregation. Experimental formulation screens are typically based on thermal transition midpoints ( T m ), and forced degradation studies at elevated temperatures. Both approaches give limited predictions of long-term storage stability, particularly at low temperatures. Better understanding of the mechanisms of action for formulation of excipients and buffers could lead to improved strategies for formulation design. Here, we identified a complex impact of glycine concentration on the experimentally determined stability of an antibody Fab fragment and then used molecular dynamics simulations to reveal mechanisms that underpin these complex behaviors. T m values increased monotonically with glycine concentration, but associated Δ S vh measurements revealed more complex changes in the native ensemble dynamics, which reached a maximum at 30 mg/mL. The aggregation kinetics at 65 °C were similar at 0 and 20 mg/mL glycine, but then significantly slower at 50 mg/mL. These complex behaviors indicated changes in the dominant stabilizing mechanisms as the glycine concentration was increased. MD revealed a complex balance of glycine self-interaction, and differentially preferred interactions of glycine with the Fab as it displaced hydration-shell water, and surface-bound water and citrate buffer molecules. As a result, glycine binding to the Fab surface had different effects at different concentrations, and led from preferential interactions at low concentrations to preferential exclusion at higher concentrations. During preferential interaction, glycine displaced water from the Fab hydration shell, and a small number of water and citrate molecules from the Fab surface, which reduced the protein dynamics as measured by root-mean-square fluctuation (RMSF) on the short time scales of MD. By contrast, the native ensemble dynamics increased according to Δ S vh , suggesting increased conformational changes on longer time scales. The aggregation kinetics did not change at low glycine concentrations, and so the opposing dynamics effects either canceled out or were not directly relevant to aggregation. During preferential exclusion at higher glycine concentrations, glycine could only bind to the Fab surface through the displacement of citrate buffer molecules already favorably bound on the Fab surface. Displacement of citrate increased the flexibility (RMSF) of the Fab, as glycine formed fewer bridging hydrogen bonds to the Fab surface. Overall, the slowing of aggregation kinetics coincided with reduced flexibility in the Fab ensemble at the very highest glycine concentrations, as determined by both RMSF and Δ S vh , and occurred at a point where glycine binding displaced neither water nor citrate. These final interactions with the Fab surface were driven by mass action and were the least favorable, leading to a macromolecular crowding effect under the regime of preferential exclusion that stabilized the dynamics of Fab.

The deterioration of CaO-SiO2 based mold flux caused by the reaction of steel -slag interface is a bottleneck restricting the high Mn-Al steel continuous casting production efficiently. Therefore, the development of low-reactivity mold flux has become a research hotspot. In this paper, the scheme of high Al2O3 and low SiO2 was adopted to suppress or reduce the occurrence of steel-slag reaction. Drawing binary phase diagram of mold flux based on the CaO–Al2O3 composition, the influence of different solvents on the melting characteristics of the mold flux were investigated and the reasonable mass ratio of CaO/Al2O3and the content of SiO2, SrO, MgO, Na2O and B2O3 were determined. According to the viscosity and the melting temperature model calculation, the physical property is beneficial for the composition design of low-reactivity mold flux.

In recent years, the demand for energy-efficient technological solutions in the building sector has risen significantly worldwide. The exploitation of phase change material as a medium for thermal energy storage in building envelopes has increased due to its superior properties. There is still a knowledge gap to cover in the way to the effective solar thermal energy storage in the building envelope – to enhance the heat transfer, to reduce the heat loss, etc. This paper deals with the optimisation of heat transfer using a solar concentrator (Fresnel lens). This study examines the effect of Fresnel lens focal point location on heat transfer in a dynamic solar facade prototype that stores thermal energy in phase change material. Nine different setups (solar façade compositions) were tested in the laboratory – two parameters with three alternatives each. Testing conditions simulate the relevant Northern Europe climate. By changing the air gap configuration and location of the Fresnel lens focal point, the heat transfer to phase change material was observed by measuring temperatures in the phase change material container using five thermocouples. The results show the improved thermal performance in test modules with larger cone diameter by 7.2 % and Fresnel lens focal point positioning closer to the back of the phase change material container by 5.4 %.

When synthesizing a gene with a long DNA sequence, it is usually necessary to divide it into several fragments. Based on these fragments, a set of oligonucleotides for gene assembly is produced. Each oligonucleotide is synthesized separately by the chemical reaction, and then the obtained oligonucleotides are assembled into the full gene sequence, in a specific environment, by polymerase chain reaction (PCR) or ligase chain reaction (LCR). In this paper, an effective and efficient algorithm to divide long genes into oligonucleotide sets is presented. First, according to the length of the overlapping oligonucleotide region, the long DNA sequence to be synthesized is divided into fragments of approximately equal length. Second, the length of these fragments is iterated to dynamically optimize the length of the overlapping regions to reduce melting temperature fluctuations. Then, the improved depth-first search algorithm is used according to the design principle of pruning optimization to obtain a uniform set of oligonucleotides with very close melting temperatures. This will decrease the errors in gene assembly with PCR or LCR. Lastly, the oligonucleotides that have homologous melting temperatures needed for PCR-based synthesis and two-step assembly of the target gene are deduced and outputted.

A molecular dynamics (MD) simulation method with the embedded atom model (EAM)/alloy potential was used to investigate the thermomechanical properties of nanoscale hollow palladium (Pd) nanoparticle pairs during additive manufacturing (AM). The purpose was to explore and analyze hollow Pd nanoparticle pairs at room temperature obtained by AM. The thermomechanical properties of the hollow Pd nanoparticle pairs were discussed with the aim of proposing optimal parameters. It was shown that the nanoscale coalescence temperature of Pd was in the range of 750 to 1530 K and the nanoscale melting temperature was from 1414 to 1600 K, which were much lower than the macroscopic melting point (1828.05 K) of Pd. It was found that solid-state sintering can occur spontaneously at room temperature. The size and geometrical structure of the nanoparticles and the heating rate played important roles during AM. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The properties of manganese-containing phosphate and borophosphate glasses were studied: melting temperature, melt viscosity, homogeneity, and thermal and chemical stability. The studied compositions of the matrices meet the regulatory requirements of the vitrification department in terms of melting temperature and melt viscosity. Almost all tempered (original) glasses are X-ray amorphous. Thermal tests of glasses at a temperature of 450°C lead mainly to surface crystallization of samples and, in some cases, to volumetric crystallization. All phosphate glasses are chemically stable provided they contain Al2O3 within the prescribed values (14–18 wt %), while borophosphate glasses are stable at a high content of Al2O3 (approximately 19.6 wt %). The possibility to include MnO2 into glasses in the investigated range (from 2 to 7.25 wt %) is shown. [ABSTRACT FROM AUTHOR]

The physical property changes in the plasma‐polymerized fluorocarbon (PPFC) thin films near the melting temperature (Tm) were investigated through chemical structure analysis. The PPFC thin films, produced by semi‐crystalline polytetrafluoroethylene (PTFE)‐based polymer sputtering target, form amorphous polymers with outstanding properties, such as high water repellency and high optical transmittance, electrical insulation, and chemical resistance. Interestingly, in‐situ X‐ray photoelectron spectroscopy analysis revealed that the PPFC thin films maintained their physical properties at temperatures above the Tm in vacuum and exhibited properties similar to those of bulk PTFE while maintaining amorphous structure. Therefore, this thin film can be applied to various devices and surface coatings manufactured at high temperatures. [ABSTRACT FROM AUTHOR]

Surface atoms and dangling bonds on the surface affect the thermodynamic properties. A thermodynamical model, based on cohesive energy is presented to discuss the melting properties of materials at nanoscale. The model is used to realize the effect of size and shape on melting temperature Tmn, melting entropy Smn and enthalpy Hmn of Ni, Sn, Al and Cu metallic nanoparticles. The variation in Tmn, Smn and Hmn are examined for nanowire, film, spherical, regular tetrahedral, hexahedral and octahedral shaped nanoparticles. It is reported that Tmn, Smn and Hmn decrease with decreasing the size of the nanoparticles and smaller the particle size, greater are the size and shape effects and when size is less than 10 nm, it has been predicted that on decreasing size, Tmn, Smn and Hmn reduce appreciably. Also, at the same size, more the shape of nanoparticles departs from that of the sphere, smaller is the Smn and Hmn of nanoparticles and its changes are less for nanowire shape and more for regular tetrahedral shape. Our theoretical results are compared with the available experimental or simulation data. Results predicted by our model are in good agreement with experimental observations. [ABSTRACT FROM AUTHOR]

The spectral experiment, hemispherical melting point apparatus, rotating cylinder method, and four-probe method are conducted to measure the structure, melting temperature, apparent viscosity and electrical conductivity of aluminate slag. The results show that in order to reduce the comprehensive effect of capacitance and inductance, the frequency of value 6000 Hz corresponding to the minimum impedance is most suitable for the electrical conductivity measurement. Higher B2O3 content leads to a lower degree of polymerization, symmetry, and uniformity in the complex three-dimensional structure of the slag, meanwhile the slag hemispheric temperature declines gradually, which enhances the slag superheat, hence decreases the apparent viscosity and increases the electrical conductivity comprehensively, as well as the relation between viscosity logarithm and the conductivity logarithm at 1300 °C was linear. The breaking temperature of apparent viscosity-temperature curve reduces gradually with B2O3 addition, while the conductivity-temperature curve indicate that the slag crystallized at about 1210 to 1224 °C, and with the lower B2O3 content, the crystallization trend is more obvious. [ABSTRACT FROM AUTHOR]

Taking melting-separated red mud as the research object, the change law of melt properties was explored in the process of melting-separated red mud slag fibrosis. The melting process and melting temperature of melting-separated red mud were studied by slag melting point and melting rate tester. FactSage thermodynamic software was used to simulate the mineral precipitation type, content and initial crystallization temperature during the cooling process of melting-separated red mud slag. X-ray diffractometer and field emission scanning electron microscope were used to study the mineral composition and micro-morphology of melting-separated red mud slag at different temperatures. The viscosity change of meltingseparated red mud slag during the cooling process was studied by using the comprehensive tester of melt physical properties. The results show that the melting temperature of melting-separated red mud is 1 236 . During the cooling process of melting-separated red mud slag, crystals begin to precipitate at 1 300 . At first, magnesium aluminate spinel (MgAl2 O4 ) is precipitated. In addition, after comprehensive analysis of melt properties of melting-separated red mud slag, it is clear that the temperature of preparing inorganic fiber by fiberizing melting-separated red mud slag should be higher than 1 433 . [ABSTRACT FROM AUTHOR]

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To develop agar derivatives with good antibacterial activity and decreased gelling and melting temperatures, two agar–gentamycin conjugates with 9.20% and 12.68% gentamicin immobilized were fabricated by oxidation, Schiff base and reduction reaction, and characterized by a Fourier Transform Infrared Spectrometer, 1H nuclear magnetic resonance and an elemental analyzer. It was found that the modifications changed the intermolecular interactions, leading to decreased gelling and melting temperatures for the oxidized agar and slightly increased gelling and melting temperatures for agar–gentamycin conjugates. Further studies of antimicrobial properties showed that the two agar–gentamycin conjugates possessed good antibacterial activity, which was positively correlated with the dosage and the immobilization rate of gentamicin. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of agar–gentamycin conjugates with higher immobilization rates of gentamicin against Escherichia coli were 39.1 μg/mL and 156.2 μg/mL, respectively, and the MICs and MBCs against Staphylococcus aureus were 19.5 μg/mL and 78.1 μg/mL, respectively. A biofilm test indicated that certain concentrations of agar–gentamycin conjugate could effectively inhibit the biofilm formation of Escherichia coli and Staphylococcus aureus. In summary, agar–gentamycin conjugates possess good antibacterial activities and may be applied as a new kind of antibacterial material. [ABSTRACT FROM AUTHOR]

This study aimed to produce freeze-dried inclusion complex of cinnamon essential oil (CEO) using β-cyclodextrin (BCD) and γ-cyclodextrin (GCD) as wall materials in two selected weight ratios (85/15 and 80/20). Encapsulation efficiency (EE) of CEO was significantly higher when the CD/CEO ratio was maintained at 80/20. Additionally, the GCD exhibited an excellent EE (96.5%) than the BCD (71.02%). Various analytical techniques, including Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry, X-ray diffraction, scanning electron microscopy, and rheological measurements demonstrated that the CEO was efficiently encapsulated in the cavity of cyclodextrins. Rheological data of CD and CEO in solution were fitted to the Herschel-Bulkley and Cross model well. The antimicrobial activity of the inclusion complexs (ICs) displayed that the CEO in GCD (80/20) had the excellent inhibitory effect against Listeria monocytogenes, and Salmonella enterica sv Typhimurium. Overall, the GCD acts as a superior wall material by forming an excellent IC with CEO with desirable properties. The obtained results demonstrated that both encapsulates would have potential for use as intermediate materials in antimicrobial food packaging. [ABSTRACT FROM AUTHOR]

FeH x is a crucial mineral in geophysics, but its melting properties remain poorly understood at high pressures. In this Short Communication, we introduce a simple analytical model to access the solid–liquid boundary of FeH x with minimal time and cost. Inspired by the work-heat equivalence principle, our model allows geophysicists to effectively exploit available ab initio resources to directly deduce the melting temperature of FeH x from its equation of state. The obtained results agree quantitatively with cutting-edge atomistic simulations throughout a wide range of hydrogen content and hydrostatic pressure. Therefore, our analyses would have implications for elucidating the internal dynamics of rocky worlds within and beyond our Solar System. • The melting temperature of FeHx is determined up to 1575 GPa via the modified work-heat equivalence principle. • A quantitative agreement between theory and simulation is achieved. • The core crystallization of super-Earths would occur from the bottom up. • The presence of FeHx near Earth's core-mantle boundary can explain the origin of ultralow-velocity zones outside large low-velocity provinces. [ABSTRACT FROM AUTHOR]

BACKGROUND The measurement of 40Ar content in K-Ar dilution method includes sample melting and releasing gas, gas purification and enrichment, mass spectrometry measurement. With the application of a newly designed double vacuum furnace and gas purification system, the experiment process gradually changes from manual operation to automatic program control, but the parameters are unclear. OBJECTIVES To determine the parameters by conditional experiments and establish a complete measurement method of 40Ar content in K-Ar dilution method. METHODS Parameters were determined by releasing and absorbing an air standard in activated carbon cold finger with different times, melting different types of samples with different temperatures of the double vacuum furnace. The method reliability was verified by K-Ar dating for SK01 sanidine standard. RESULTS The optimal heating release time for activated carbon cold finger was 500s, and the adsorption time was 200s. Using these conditions, the gas produced by the melting in the furnace can be completely transferred and released to avoid isotope fractionation. The corresponding melting temperature was used for different types of samples to ensure that the samples were completely melted and outgassed, the melting temperature of the furnace for clay minerals, biotite, and muscovite should be set to 1400℃, and 1500℃ for amphibole, 1550℃ for basic rock, and 1600℃for potassium feldspar. The K-Ar dating of 10 sets of SK01 sanidine standards showed that the results were consistent with 40Ar-39Ar dating ages. CONCLUSIONS The obtained condition parameters meet the accurate measurement of 40Ar content using the K-Ar dilution method.

To meet the 2050 EU decarbonization goals, there is a need for new and innovative ideas to increase energy efficiency, which includes reducing the energy consumption of buildings and increasing the use of on-site renewable energy sources. One possible solution for achieving efficient thermal energy transition in the building sector is to assign new functionalities to the building envelope. The building envelope can function as a thermal energy storage system, which can help compensate for irregularities in solar energy availability. This can be accomplished by utilizing phase change materials as the energy storage medium in the building envelope. In this paper, two phase change materials with different melting temperatures of 21 °C and 28 °C are compared for their application in a dynamic solar building envelope. Both experimental and numerical studies were conducted within the scope of this study. The laboratory testing involved simulating the conditions of the four seasons through steady-state and dynamic experiments. The performance of the phase change materials was evaluated using a small-scale PASLINK test stand that imitates indoor and outdoor conditions. A numerical model of a small-scale building envelope was created using data from laboratory tests. The purpose of this model was to investigate how the tested phase change materials perform under different climate conditions. The experimental findings show that RT21HC is better at storing thermal energy in the PCM and releasing it into the indoor area than RT28HC. On the other hand, the numerical simulation results demonstrate that RT28HC has an advantage in terms of thermal storage capacity in climates found in Southern Europe, as it prevents overheating of the room.

Surface combination structure was used to design the construction of nano and quantum films, particles, and dots. The created model was applied to tetrahedral semiconductor nanoparticles and quantum dots with a successful performance. It works better than reported experimental data across the whole size range, from the bulk state to the critical size of quantum dots. The model helps to figure out the melting point that changes with the nanosize scale as applied on Si and Sn, which are simple tetrahedral semiconductors, and for CdS and CdSe, which are among II-VI group compounds. It was also used to calculate melting-related parameters such as cohesive energy, Debye temperature, vibrational entropy, and melting enthalpy. The nanosize dependence of the lattice volume and the atom's ionization energy describes the solid surface structure. From the model, an equation was obtained to calculate the energy gaps in Si, CdS, and CdSe particles that are nano- and quantum-dot-sized, and the results are compared to the experimental data that goes with these particles. [ABSTRACT FROM AUTHOR]