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Classical thermodynamics omits rigidity, which property distinguishes solids from gases and liquids. By accounting for rigidity (i.e., Young’s elastic modulus, ϒ), we recently amended historical formulae and moreover linked heat capacity, thermal expansivity, and ϒ. Further exploration is motivation by the importance of classical thermodynamics to various applied sciences. Based on heat performing work, we show here, theoretically, that density times sublimation enthalpy divided by the molar mass (ρΔH_sub/M, energy per volume), depends linearly on ϒ (1 GPa = 10⁹ J m⁻³). Data on diverse metals, non-metallic elements, chalcogenides, simple oxides, alkali halides, and fluorides with cubic structures validate this relationship at ambient conditions. Furthermore, data on hcp metals and molecular solids show that ρΔH_sub/M is proportional to ϒ for anisotropic materials. Proportionality constants vary only from 0.1 to 0.7 among these different material types (>100 substances), which shows that the elastic energy reservoir of solids is large. Proportionality constants depend on whether molecules or atoms are sublimated and are somewhat affected by structure. We show that ductility of refractory, high-ϒ metals affect high-temperature determinations of their ΔH_sub. Our results provide information on sublimation processes and subsequent gas phase reactions, while showing that elasticity of solids is the key parameter needed to assessing their energetics. Implications are highlighted. Full article

In the framework of hydrogen production and storage for clean energy generation, the resistance to hydrogen embrittlement of a newly developed austenitic stainless steel is presented. Gas-atomized metal powders prepared from secondary-sourced metals were employed to manufacture test specimens with Laser Powder Bed Fusion (LPBF) technology. After machining and exposure to a controlled, pressurized hydrogen atmosphere at high temperature, the effect of hydrogen charging on the mechanical performance under static and dynamic conditions was investigated. The stabilizing effect of the optimized chemical composition is reflected in the absence of degradation effects on Yield Stress (YS), Ultimate Tensile Stress (UTS), and fatigue life observed for specimens exposed to hydrogen. Moreover, despite a moderate reduction in the elongation at fracture observed by increasing the hydrogen charging time, ductility loss calculated as Relative Reduction of Area (RRA) remains substantially unaffected by the duration of exposure to hydrogen and demonstrates that the austenitic steel is capable of resisting hydrogen embrittlement (HE). Full article

In order to explore the essence of the anticoccidiosis of anticoccidial drugs under bioelectric currents, the intermolecular double-proton transfer and conformational transformation of 4-pyridone-3-carboxylic acid were investigated by quantum chemistry calculations (at the M06-2X/6-311++G**, M06-2X/aug-cc-pVTZ and CCSD(T)/aug-cc-pVTZ levels) and finite temperature string (FTS) under external electric fields. The solvent effect of H₂O on the double-proton transfer was evaluated by the integral equation formalism polarized continuum model. The results indicate that the influences of the external electric fields along the direction of the dipole moment on double-proton transfer are significant. The corresponding products are controlled by the direction of the external electric field. Due to the first-order Stark effect, some good linear relationships form between the changes of the structures, atoms in molecules (AIMs) results, surface electrostatic potentials, barriers of the transition state, and the external electric field strengths. From the gas to solvent phase, the barrier heights increased. The spatial order parameters (ϕ, ψ) of the conformational transformation could be quickly converged through the umbrella sampling and parameter averaging, and thus the free-energy landscape for the conformational transformation was obtained. Under the external electric field, there is competition between the double-proton transfer and conformational transformation. The external electric field greatly affects the cooperativity transfer, while it has little effect on the conformational transformation. This study is helpful in the selection and updating of anticoccidial drugs. Full article

In this paper, the first demonstration of a highly strained In_0.8Ga_0.2As/In_0.2Ga_0.8Sb type-II superlattice structure grown on InAs substrates by molecular beam epitaxy (MBE) for long-wavelength infrared detection was reported. Novel methodologies were developed to optimize the As and Sb flux growth conditions. The quality of the epitaxial layer was characterized using multiple analytical techniques, including differential interference contrast microscopy, atomic force microscopy, high-resolution X-ray diffraction, and high-resolution transmission electron microscopy. The high-quality superlattice structure, with a total thickness of 1.5 μm, exhibited exceptional surface morphology with a root-mean-square roughness of 0.141 nm over a 5 × 5 μm² area. Single-element devices with PIN architecture were fabricated and characterized. At 77 K, these devices demonstrated a 50% cutoff wavelength of approximately 12.1 μm. The long-wavelength infrared PIN devices exhibited promising performance metrics, including a dark current density of 7.96 × 10⁻² A/cm² at −50 mV bias and a high peak responsivity of 4.90 A/W under zero bias conditions, both measured at 77 K. Furthermore, the devices achieved a high peak quantum efficiency of 65% and a specific detectivity (D*) of 2.74 × 10¹⁰ cm·Hz^1/2/W at the peak responsivity wavelength of 10.7 µm. These results demonstrate the viability of this material system for long-wavelength infrared detection applications. Full article

Against the backdrop of global energy transition and strict environmental regulations, supercritical carbon dioxide (scCO₂) fracturing and oil displacement technologies have emerged as pivotal green approaches in shale gas exploitation, offering the dual advantages of zero water consumption and carbon sequestration. However, the inherent low viscosity of scCO₂ severely restricts its sand-carrying capacity, fracture propagation efficiency, and oil recovery rate, necessitating the urgent development of high-performance thickeners. The current research on scCO₂ thickeners faces a critical trade-off: traditional fluorinated polymers exhibit excellent philicity CO₂, but suffer from high costs and environmental hazards, while non-fluorinated systems often struggle to balance solubility and thickening performance. The development of new thickeners primarily involves two directions. On one hand, efforts focus on modifying non-fluorinated polymers, driven by environmental protection needs—traditional fluorinated thickeners may cause environmental pollution, and improving non-fluorinated polymers can maintain good thickening performance while reducing environmental impacts. On the other hand, there is a commitment to developing non-noble metal-catalyzed siloxane modification and synthesis processes, aiming to enhance the technical and economic feasibility of scCO₂ thickeners. Compared with noble metal catalysts like platinum, non-noble metal catalysts can reduce production costs, making the synthesis process more economically viable for large-scale industrial applications. These studies are crucial for promoting the practical application of scCO₂ technology in unconventional oil and gas development, including improving fracturing efficiency and oil displacement efficiency, and providing new technical support for the sustainable development of the energy industry. This study innovatively designed an amphiphilic modified amino silicone oil polymer (MA-co-MPEGA-AS) by combining maleic anhydride (MA), methoxy polyethylene glycol acrylate (MPEGA), and amino silicone oil (AS) through a molecular bridge strategy. The synthesis process involved three key steps: radical polymerization of MA and MPEGA, amidation with AS, and in situ network formation. Fourier transform infrared spectroscopy (FT-IR) confirmed the successful introduction of ether-based CO₂-philic groups. Rheological tests conducted under scCO₂ conditions demonstrated a 114-fold increase in viscosity for MA-co-MPEGA-AS. Mechanistic studies revealed that the ether oxygen atoms (Lewis base) in MPEGA formed dipole–quadrupole interactions with CO₂ (Lewis acid), enhancing solubility by 47%. Simultaneously, the self-assembly of siloxane chains into a three-dimensional network suppressed interlayer sliding in scCO₂ and maintained over 90% viscosity retention at 80 °C. This fluorine-free design eliminates the need for platinum-based catalysts and reduces production costs compared to fluorinated polymers. The hierarchical interactions (coordination bonds and hydrogen bonds) within the system provide a novel synthetic paradigm for scCO₂ thickeners. This research lays the foundation for green CO₂-based energy extraction technologies. Full article

This study investigates the development of silver (Ag)-doped zirconia (ZrO₂) coatings deposited on 316LVM stainless steel via the unbalanced magnetron sputtering technique. The oxygen content in the Ar/O₂ gas mixture was systematically varied (12.5%, 25%, 37.5%, and 50%) to assess its influence on the resulting coating properties. In response to the growing demand for biomedical implants with improved durability and biocompatibility, the objective was to develop coatings that enhance both wear and corrosion resistance in physiological environments. The effects of silver incorporation and oxygen concentration on the structural, tribological, and electrochemical behavior of the coatings were systematically analyzed. X-ray diffraction (XRD) was employed to identify crystalline phases, while atomic force microscopy (AFM) was used to characterize surface topography prior to wear testing. Wear resistance was evaluated using a ball-on-plane tribometer under simulated prosthetic motion, applying a 5 N load with a bone pin as the counter body. Corrosion resistance was assessed through electrochemical impedance spectroscopy (EIS) in a physiological solution. Additionally, tribocorrosive performance was investigated by coupling tribological and electrochemical tests in Ringer’s lactate solution, simulating dynamic in vivo contact conditions. The results demonstrate that Ag doping, combined with increased oxygen content in the sputtering atmosphere, significantly improves both wear and corrosion resistance. Notably, the ZrO₂-Ag coating deposited with 50% O₂ exhibited the lowest wear volume (0.086 mm³) and a minimum coefficient of friction (0.0043) under a 5 N load. This same coating also displayed superior electrochemical performance, with the highest charge transfer resistance (38.83 kΩ·cm²) and the lowest corrosion current density (3.32 × 10⁻⁸ A/cm²). These findings confirm the high structural integrity and outstanding tribocorrosive behavior of the coating, highlighting its potential for application in biomedical implant technology. Full article

Spherical powder materials are essential raw materials for manufacturing processes such as metal additive manufacturing and powder metallurgy. They possess characteristics that are key factors influencing the performance of additive manufacturing. This paper introduces the fundamental principles and characteristics of laser additive manufacturing technology and analyzes the technical principles, advantages, and disadvantages of three alloy powder preparation methods: gas atomization, centrifugal atomization, and plasma atomization. It further elucidates the influence of process parameters of these three powder preparation techniques on the characteristics of alloy powders. Finally, the development trends in alloy powder preparation for laser additive manufacturing are projected. Full article

After reviewing the state of the art of the fluorination of inorganic solid electrolytes, an application of gas/solid fluorination is given and how it can be processed. Garnet-type oxide has been chosen. These oxides with an ideal structure of chemical formula A₃B₂(XO₄)₃ are mainly known for their magnetic and dielectric properties. Certain garnets may have a high enough Li⁺ ionic conductivity to be used as solid electrolyte of lithium ion battery. The surface of LLZO may be changed in contact with the moisture and CO₂ present in the atmosphere that results in a change of the conductivity at the interface of the solid. LiOH and/or lithium carbonate are formed at the surface of the garnet particles. In order to allow for handling and storage under normal conditions of this solid electrolyte, surface fluorination was performed using elemental fluorine. When controlled using mild conditions (temperature lower or equal to 200 °C, either in static or dynamic mode), the addition of fluorine atoms to LLZO with Li_6,4Al_0,2La₃Zr₂O₁₂ composition is limited to the surface, forming a covering layer of lithium fluoride LiF. The effect of the fluorination was evidenced by IR, Raman, and NMR spectroscopies. If present in the pristine LLZO powder, then the carbonate groups disappear. More interestingly, contrary to the pristine LLZO, the contents of these groups are drastically reduced even after storage in air up to 45 days when the powder is covered with the LiF layer. Surface fluorination could be applied to other solid electrolytes that are air sensitive. Full article

The spray evaporation process in the boiler desuperheater involves complex droplet behaviors and fluid–thermal coupling, and its temperature distribution characteristics greatly affect the performance and safety of industrial processes. To better understand the process characteristics and develop the optimal desuperheater design, computational fluid dynamics (CFDs) was applied to numerically investigate the flow and thermal characteristics. The Eulerian–Lagrangian approach was used to describe the two-phase flow characteristics. Both primary and secondary droplet breakup, the coupling effect of gas–liquid and stochastic collision and coalescence of droplets were considered in the model. The plain-orifice atomizer model was applied to simulate the atomization process. The numerical model was validated with the plant data. The spray tube structure was found to greatly affect the flow pattern, resulting in the uneven velocity distribution, significant temperature difference, and local reverse flow downstream of the orifices. The velocity and temperature distributions tend to be more uniform due to the complete evaporation and turbulent mixing. Smaller orifices are beneficial for generating smaller-sized droplets, thereby promoting the mass and heat transfer between the steam and droplets. Under the same operating conditions, the desuperheating range of cases with 21, 15, and 9 orifices is 33.7 K, 32.0 K, and 29.8 K, respectively, indicating that the desuperheater with more orifices (i.e., with smaller orifices) shows better desuperheating ability. Additionally, a venturi-type desuperheater was numerically studied and compared with the straight liner case. By contrast, discernible differences in velocity and temperature distribution characteristics can be observed in the venturi case. The desuperheating range of the venturi and straight liner cases is 38.1 K and 35.4 K, respectively. The velocity acceleration through the venturi throat facilitates the droplet breakup and improves mixing, thereby achieving better desuperheating ability and temperature uniformity. Based on the investigation of the spray evaporation process, the complex droplet behaviors and fluid–thermal coupling characteristics in an industrial boiler desuperheater under high temperature and high pressure can be better understood, and effective guidance for the process and design optimizations can be provided. Full article

Mesoporous silicon dioxide films have been shown to be well suited as adhesion-promoting interlayers for generating high-strength polymer–metal interfaces. These films can be fabricated via microwave plasma-enhanced chemical vapor deposition using the precursor hexamethyldisiloxane and oxygen as working gas. The resulting mesoporous structures enable polymer infiltration during overmolding, which leads to a nanoscale form-locking mechanism after solidification. This mechanism allows for efficient stress transfer across the interface and makes the resulting adhesion highly dependent on the morphology of the deposited film. To gain a deeper understanding of the underlying deposition mechanisms and improve process stability, this work investigates the growth behavior of mesoporous silica films using a multiple regression analysis approach. The seven process parameters coating time, distance, chamber pressure, substrate temperature, flow rate, plasma pulse duration, and pause-to-pulse ratio were systematically varied within a Design of Experiments framework. The resulting films were characterized by their free surface area, mean agglomerate diameter, and film thickness using digital image analysis, white light interferometry, and atomic force microscopy. The deposited films exhibit a wide range of morphological appearances, ranging from quasi-dense to dust-like structures. As part of this research, the free surface area varied from 15 to 55 percent, the mean agglomerate diameter from 17 to 126 nm, and the film thickness from 35 to 1600 nm. The derived growth model describes the deposition process with high statistical accuracy. Furthermore, all coatings were overmolded via injection molding and subjected to mechanical testing, allowing a direct correlation between film morphology and their performance as adhesion-promoting interlayers. Full article

The GaN-based green miniaturized light-emitting diode (mini-LED) is a key component for the realization of full-color display. Optimized passivation layers can alleviate the trapping of carriers by sidewall defects and are regarded as an effective way to improve the external quantum efficiency (EQE) efficiency of mini-LEDs. Since AlN has a closer lattice match to GaN compared to other heterogeneous passivation materials, we boosted the EQE of GaN-based green flip-chip mini-LEDs through the deposition of a lattice-compatible AlN passivation layer through atomic layer deposition (ALD) and a SiO₂ passivation layer through plasma-enhanced chemical vapor deposition (PECVD). Benefiting from reduced sidewall nonradiative recombination, the EQE of the green flip-chip mini-LED with a composite ALD-AlN/PECVD-SiO₂ passivation layer reached 34.14% at 5 mA, which is 34.6% higher than that of the green flip-chip mini-LED with a single PECVD-SiO₂ passivation layer. The results provide guidance for the realization of high-performance mini-LEDs by selecting lattice-compatible passivation layers. Full article

Monitoring SF₆ decomposition gases has emerged as a vital diagnostic technique for evaluating insulation conditions and identifying faults in SF₆-based electrical equipment. This study comprehensively explores the adsorption properties and sensing capabilities of a Pd-doped InSe (Pd-InSe) monolayer for SF₆ decomposition gases, including SO₂, SOF₂, and SO₂F₂, through density functional theory calculations. The Pd-InSe monolayer is constructed by substituting one Se atom with a Pd atom in the pristine InSe structure. Then, the Pd doping effect on the InSe monolayer and the adsorption behaviors of the Pd-InSe monolayer for three gases are thoroughly examined. The adsorption configurations, charge density differences, and electron localization functions are scrutinized to elucidate the gas adsorption mechanisms of the Pd-InSe monolayer; and the band structures, along with the density of states, are analyzed to gain insights into the resistive gas sensing mechanisms for detecting these three gases. Finally, the temperature-dependent recovery characteristics are evaluated to assess the reusability of the monolayer. These findings not only underscore the potential of the Pd-InSe monolayer for sensing SF₆ decomposition gases but also open new avenues for the development of next-generation 2D materials in gas sensing applications within the field of electrical engineering. Full article

The initial surface reaction of gallium nitride (GaN) grown by atomic layer deposition (GaN-ALD) was investigated using density functional theory (DFT) calculations. Trimethylgallium (TMG) and ammonia (NH₃) were used as gallium (Ga) and nitrogen (N) precursors, respectively. DFT calculations at the B3LYP/6-311+G(2d,p) and 6-31G(d) levels were performed to compute relative energies and optimize chemical structures, respectively. TMG adsorption on Si₁₅H₁₈–(NH₂)₂ and Si₁₅H₂₀=(NH)₂ clusters was modeled, where –NH₂ and =NH surface species served as adsorption sites. The reaction mechanisms in the adsorption and nitridation steps were investigated. The results showed that TMG can adsorb on both surface adsorption sites. In the initial adsorption stage, TMG adsorbs onto =NH- and –NH₂-terminated Si(100) surfaces with activation energies of 1.11 and 2.00 eV, respectively, indicating that the =NH site is more reactive. During subsequent NH3 adsorption, NH₃ adsorbs onto the residual TMG on the =NH- and –NH₂-terminated surfaces with activation energies of approximately 2.00 ± 0.02 eV. The reaction pathways indicate that NH₃ adsorbs via similar mechanisms on both surfaces, resulting in comparable nitridation kinetics. Furthermore, this study suggests that highly reactive NH₂⁻ species generated in the gas phase from ionized NH₃ may help reduce the process temperature in the GaN-ALD process. Full article

In this study, we present a basic idea for a robust optical measurement method for the practical monitoring of slurry sprays with high mass concentrations, as typically used in combustion processes. The proposed approach is based on analyzing the transparency properties of individual dynamic droplets within the slurry spray. These so-called dynamic slurry droplets consist of a base fluid and suspended solid particles. Our method enables the determination of the mass concentration of solid particles and provides an estimate of their average size. The resolution of this technique allows for the detection of errors in the slurry-mixing process and even in the milling process of the solid particles prior to mixing. To atomize slurries with high mass concentration, an experimental setup with a gas-assisted coaxial nozzle was employed. Slurries with three different mass concentrations and three particle size distributions were tested, resulting in five combinations. The theoretical expectations and experimental results show a strong correlation, highlighting the potential of the proposed method for slurry-spray monitoring. Full article

The pyrolysis of polymers is a thermal processing method largely used to convert polymeric waste into valuable products such as oils and carbonaceous residues. The NP-gram method (NP standing for normal paraffins) is useful for the global characterisation of pyrolysis oils with complex composition. Here, we present the fundamental of this method, which is based on the concept of “carbon number”, in conjunction with the boiling point and the chromatographic retention time of chemical compounds. Polypropylene was selected as the model polymer due to its simple mechanism of thermal degradation. The boiling points of the main compounds in polypropylene pyrolysis oil were estimated based on the equations of Egloff and Wiener. A good correspondence was obtained for the estimated boiling points and the position of the compounds in the gas chromatogram. A distinction was made between the number of carbon atoms in the molecule and the corresponding carbon number used in characterisation of pyrolysis oils by NP-gram. Correlation with the chromatographic retention index was also discussed. The application of the NP-gram method for different polymers was also presented. Full article