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The centrifugal atomization process is a rapid solidification method that achieves high cooling rates. Although this technique is typically used to produce common metal powders, it has not been extensively explored for amorphous powder production, despite its clear advantage of generating nearly perfect spherical particles, which is beneficial for subsequent powder consolidation. In this paper, a characterization of three iron-based alloys from the Fe-Si-B system, specifically Fe91.72Si5.32B2.96 (wt%), Fe87.37Si6.94B2.49Cr2.46C0.75 (wt%), and Fe89.41Si2.02B1.13P5.89C1.55 (wt%), produced by centrifugal atomization, is presented. The amorphous fractions of the powders were quantified using DSC, with further characterization performed via optical microscopy, SEM, and XRD. The amorphous fractions increased with the addition of Cr, C, and P, reaching up to 90% in the Fe89.41Si2.02B1.13P5.89C1.55 alloy for particles of <100 μm. The onset cooling rates were estimated to be approximately 10⁶ K/s for Fe91.7Si5.32B3, 10⁵ K/s for Fe87.36Si6.9B2.48Cr2.45C0.75, and 10⁴ K/s for Fe89.41Si2.02B1.13P5.89C1.55, respectively. [ABSTRACT FROM AUTHOR]

The use of unmanned aerial spraying systems is currently being explored and applied worldwide. The objective of this study was to characterize the droplet population generated by hydraulic nozzles and centrifugal atomization nozzles used in sprayers mounted on remotely piloted aircraft (RPA). Two spray nozzle technologies were tested using a Malvern SprayTech laser particle size meter. The hydraulic nozzle evaluated was model 11001, which generates a wide-use fan spray. The centrifugal atomization nozzle, used in RPA sprayers, was manufactured by Yuenhoang, model DC12V. The experimental design was implemented in a completely randomized scheme, containing variations in the nozzles (hydraulic nozzle and centrifugal atomization nozzle) and application rate (AR) (5, 10, and 15 L ha−1 in the test with the hydraulic nozzle; and 9.2, 12.8, and 15.6 L ha−1 in the test with the centrifugal nozzle), with five replicates per treatment. The hydraulic nozzle test data showed a coefficient of variation of 6.8% VMD for all treatments, with droplet sizes within the fine classification ranging from 132.8 to 163.2 µm. It is noteworthy that the average relative span (span) of the droplet population generated by the hydraulic nozzle was 1.2, i.e., 20% higher than the desired reference value of 1. This value exceeds the general average reported for the centrifugal atomization nozzle, which has a span of 1.1. The relative span of the droplet size distribution for the hydraulic nozzles is greater than that observed with the centrifugal atomization nozzles. Excluding the extreme rotational speeds of the centrifugal atomization nozzle, the percentage of droplets generated with a volume smaller than 100 µm is lower compared to those produced by the hydraulic nozzle. [ABSTRACT FROM AUTHOR]

Ultrasonic atomization is an object of steadily increasing interest from metal powder manufacturers, both for additive manufacturing and powder metallurgy. Based on the analysis of available theoretical studies, simulations and experiments, it was noted that the average particle size after atomization and the final particle size distribution depend on the process parameters (e.g., frequency, amplitude) and the parameters of the atomized fluid (e.g., viscosity, surface tension). The objective of this study is to evaluate the feasibility of using ultrasonic atomization to study the properties of liquid metals. It attempts to close a gap in existing knowledge in searching for a new, possibly simple and cost-effective method to study the properties of liquid metals and clarify the relationship between ultrasonic atomization parameters (amplitude, frequency, metal spill on vibrating surface) and obtained atomization results (average particle size, particle size distribution, atomization time). Utilizing numerical modeling as a methodology, especially the finite element method, the possibilities of using ultrasonic atomization as an instrument to determine properties of liquid metals were considered as an introduction to a series of real experiments. Modeling was applied to liquids with different properties, atomized at a chosen specific constant frequency and amplitude. The results of the simulation are in line with the current state of knowledge about ultrasonic atomization. However, in the existing studies available to the authors, there are no data that can be compared directly, but indirect comparisons confirmed the conclusions of the preliminary literature analysis. The relationship between viscosity and surface tension and the average size of the atomization processes obtained in the simulation of particles was demonstrated, thus providing a tool for the development of the presented concept: ultrasonic atomization as a research method. Research and simulation results led to the final conclusion: ultrasonic atomization can be applied to study the properties of liquid metals and this will be the subject of further research and experimentation. [ABSTRACT FROM AUTHOR]

The nozzle is a crucial component in unmanned aerial vehicle (UAV) sprayers. The centrifugal nozzle offers unique advantages; however, there is a scarcity of published research regarding the structural parameters, spraying parameters, and practical applications specifically for UAV spraying. Furthermore, there is a need for UAV-specific nozzles that demonstrate high efficiency and excellent atomization performance. In this present study, a multi-disc centrifugal nozzle (MCN) capable of controlling droplet size was designed and optimized. The droplet size spectra with different atomizing discs were tested, and indoor and field tests were conducted to investigate the atomization and spray deposition characteristics of the MCN. It was found that the MCN with six atomizing discs with a curved groove, a disc angle of 120°, and a disc diameter of 77 mm demonstrated better atomizing performance. The volume median diameter was 96–153 μm, and the relative span was 1.0–1.3. Compared with the conventional hydraulic nozzle, this nozzle increased the effective spray swath width from 2.5–3.0 m to 4.0–5.0 m and promoted the average deposition rate by 132.4% at a flying height of 1.0 m and a flying speed of 3.0 m/s, which tends to raise the operation efficiency by four to five times. This study can provide a reference for the design and optimization of centrifugal nozzles for a UAV sprayer and the selection of operating parameters in aerial spraying operations. [ABSTRACT FROM AUTHOR]

Background: Atomization plays a key role in spray drying, a process widely used in the pharmaceutical, chemical, biological, and food and beverage industries. In the pharmaceutical industry, spray drying is particularly important in the preparation of amorphous solid dispersions, which enhance the bioavailability of active pharmaceutical ingredients when mixed with a polymer. Methods: In this study, a 3D-printed adaptation of a commercial spray dryer nozzle (PHARMA-SD® PSD-1, GEA Group AG) was used to investigate the atomization of PVP-VA 64 polymer solutions under varying flow conditions using high-speed diffuse back-illumination. Results: Unlike pure water, the atomization process of the polymer solution was governed by viscous effects rather than surface tension, as indicated by stringing effects in the liquid core and the formation of larger droplets. In addition, the classical Ohnesorge diagram accurately predicted the atomization regime with increasing Reynolds numbers and could be modified to reasonably predict the breakup regime by considering the transitions between regime boundaries. Conclusions: The use of such a modified diagram facilitates the efficient selection of viscous fluid solutions and process parameters to achieve complete spray formation. [ABSTRACT FROM AUTHOR]

Spray freeze drying (SFD) represents an emerging drying technique designed to produce a wide range of pharmaceuticals, foods, and active components with high quality and enhanced stability due to their unique structural characteristics. This method combines the advantages of the well-established techniques of freeze drying (FD) and spray drying (SD) while overcoming their challenges related to high process temperatures and durations. This is why SFD has experienced steady growth in recent years regarding not only the research interest, which is reflected by the increasing number of literature articles, but most importantly, the expanded market adoption, particularly in the pharmaceutical sector. Despite its potential, the high initial investment costs and complex operational requirements may hinder its growth. This paper provides a comprehensive review of the SFD technology, highlighting its advantages over conventional drying techniques and presenting its latest applications focused on pharmaceuticals. It also offers a thorough examination of the principles and the various parameters influencing the process for a better understanding and optimization of the process according to the needs of the final product. Finally, the current limitations of SFD are discussed, and future directions for addressing the economic and technical barriers are provided so that SFD can be widely industrialized, unlocking its full potential for diverse applications. [ABSTRACT FROM AUTHOR]

This study introduces a novel predictive model for atomization droplet size, developed using comprehensive data collected under elevated temperature and pressure conditions using a twin swirl airblast nozzle. The model, grounded in flow instability theory, has been meticulously parameterized using the Particle Swarm Optimization (PSO) algorithm. Through rigorous analysis, including analysis of variance (ANOVA), the model has demonstrated robust reliability and precision, with a maximum relative error of 19.3% and an average relative error of 6.8%. Compared to the classical atomization model by Rizkalla and Lefebvre, this model leverages theoretical insights and incorporates a range of interacting variables, enhancing its applicability and accuracy. Spearman correlation analysis reveals that air pressure and the air pressure drop ratio significantly negatively impact droplet size, whereas the fuel–air ratio (FAR) shows a positive correlation. Experimental validation at ambient conditions shows that the model is applicable with a reliability threshold of We1/Re1 ≥ 0.13 and highlights the predominance of the pressure swirl mechanism over aerodynamic atomization at higher fuel flow rates (q > 1.25 kg/h). This research effectively bridges theoretical and practical perspectives, offering critical insights for the optimization of airblast nozzle design. [ABSTRACT FROM AUTHOR]

To study mechanisms of jet atomization, a novel method of experimentation utilizing the resonation of diaphragms made from thin steel plates has been previously developed. In the experiments, a diaphragm covered by a film of water emitted acoustic sounds, and jet atomization from the water film was observed. Experiments using diaphragms composed of different materials and fast Fourier transformation analysis of the acoustic sound revealed that jet atomization occurred under limited surface conditions of the diaphragm and a specific range of frequency. In this article, the dynamics of a resonating body composed of the diaphragm and water film were analyzed using the finite element method with a combination of theoretical analyses of surface waves of water, such as the well-known Lang's equation. The present FEA results, from harmonic response analyses with consideration of viscous damping effect due to interaction between the diaphragm and water film, precisely confirmed the results of FFT analysis previously obtained by the experiment. Specifically, the peak frequency of the frequency response agreed well with the FFT results, and the shift of the peak frequency and attenuation due to the interaction in the analyses corresponded with the difference in surface conditions between the hydrophilic and hydrophobic materials of the diaphragm in the experiments. Our interpretation of the mechanism of jet atomization is expanded by the present numerical results. [ABSTRACT FROM AUTHOR]

The atomized reagent and synchronous jet pre-mineralization technology, as a novel method to enhance the flotation process, increases the solubility of fatty acid collectors in pulp through atomized reagent application and improves the mineralization effect and flotation rate via synchronous jet pre-mineralization technology, thereby laying a theoretical foundation for the flotation of minerals with fatty acid collectors. Systematic studies on the atomization method, atomization particle size, and flotation experiments revealed that, compared with conventional stirring methods, the atomized reagent method increases the solubility of sodium oleate in pulp from 82.5 mg/L to 142.9 mg/L at 288.15 K. The induction time for quartz particles treated with atomized reagents and bubbles is significantly lower than that of the conventional stirring method. Semi-industrial test results of the atomized reagent and synchronous jet pre-mineralization show that, compared to traditional roughing, the TFe grade increased by 0.87 percentage points, iron recovery increased by 3.95 percentage points, and reagent consumption decreased by 7.5 percentage points. Experimental and test results demonstrate that the atomized reagent and synchronous jet pre-mineralization technology can effectively enhance mineralization, accelerate the flotation rate, improve flotation indices, and reduce reagent consumption to a certain extent, providing significant guidance for the efficient recovery of fine-grained minerals. [ABSTRACT FROM AUTHOR]

The worldwide launch of neoliberalism ushered everyone into an atomized society. Neoliberalism transforms Homo sapiens into Homo economicus, a narcissistic self-entrepreneur that positions their body as a factory, skills as resources, and earnings as products while relying less on others. Such atomization of individuals undermines the community. Following the Cartesian moment, enlightenment, and postmodernism's later wave, the world is disenchanted, deprived of unity in the form of community fragmentation. Foucault offered a Greco–Roman philosophical remedy for contemporary society, focusing on the formulation of 'Spiritual-Corporality' through the practice of care of the self. Foucault believed the one who takes good care of himself is often self-assured of his ability, expectations, and missions in relationships with others, he does not resort to tyranny in those relationships, giving him an ethical advantage in caring for his family and fellow citizens. If everyone strives to take care of themselves, the city-state will prosper. However, Foucault relied on Stoic philosophy over other ancient schools and failed to provide concrete practices on how to bind ourselves with others through care of the self. In partial agreement with Foucault, the present study chooses Hadot's spiritual exercise as a more accurate terminology to justify Greco–Roman philosophies' affordance to contemporary social unification. After reviewing the philosophies of Aristotle, the Stoics, and Epicurus, the present study selected the spiritual exercises of 'hitting the mean as deliberation', 'reframing of self', and 'thinking outside the box' as suitable practices for community flourishing. [ABSTRACT FROM AUTHOR]

Plasma atomization is a technology that can produce high sphericity, small particle diameters, and high-purity copper powder, which is of great significance for the development of metal additive manufacturing. At present, although plasma atomization can realize the industrial preparation of spherical copper powder, there are still some problems, such as unclear understanding of the atomization process and a lack of theoretical support for powder quality control. This leads to the inability to predict the average particle diameter of powder in advance based on the actual atomization conditions and to optimize the process parameters, which seriously affects the further development of the plasma atomization process. We mainly studied the non-stationary simulation of a DC argon plasma torch. The purpose of this paper was to study the specific influence law of the average particle diameter of the powder in the process of plasma atomization by means of numerical simulation and experimental observation. The aim was to establish the mapping relationship between the atomization condition and the average particle diameter of the powder and realize the controllable preparation of the plasma atomized powder. At the same time, we used industrial-grade plasma atomization equipment to carry out pulverizing experiments to verify the plasma atomization theory and the powder average particle diameter control scheme proposed in this paper, thus proving the reliability of this study. [ABSTRACT FROM AUTHOR]

The quality of metal powder is essential in additive manufacturing (AM). The defects and mechanical properties of alloy parts manufactured through AM are significantly influenced by the particle size, sphericity, and flowability of the metal powder. Gas atomization (GA) technology is a widely used method for producing metal powders due to its high efficiency and cost-effectiveness. In this work, a multi-phase numerical model is developed to compute the alloy liquid breaking in the GA process by capturing the gas–liquid interface using the Coupled Level Set and Volume-of-Fluid (CLSVOF) method and the realizable k-ε turbulence model. A GA experiment is carried out, and a statistical comparison between the particle-size distributions obtained from the simulation and GA experiment shows that the relative errors of the cumulative frequency for the particle sizes sampled in two regions of the GA chamber are 5.28% and 5.39%, respectively. The mechanism of powder formation is discussed based on the numerical results. In addition, a discrete element model (DEM) is developed to compute the powder flowability by simulating a Hall flow experiment using the particle-size distribution obtained from the GA experiment. The relative error of the time that finishes the Hall flow in the simulation and experiment is obtained to be 1.9%. [ABSTRACT FROM AUTHOR]

As the flight envelopes of turbine-based combined cycle (TBCC) engines expand, ensuring reliable ignition and flame stability under varying conditions becomes increasingly critical. Previous work has shown a significantly changed ignition performance and flow pattern in cavity-based combustors when strut structure parameters were altered, indicating a strong correlation between the ignition process, flame structure, and the strut configuration. This suggests that further investigation is required to determine the optimal strut design. Therefore, this study examines the impact of various strut configurations through numerical simulations, validated by high-speed imaging. Findings show that the tail-groove strut designs improve the flame propagation performance compared to the normal struts, with a critical depth beyond which further increases do not enhance performance. Changes in strut length have a lesser impact than depth. Flow analysis indicates that tail-groove struts create additional recirculation zones that enhance fuel atomization and flame stability. These results suggest that optimizing strut configurations is vital for achieving reliable ignition and flame stability, advancing the development of efficient engines across a wide range of operational conditions. [ABSTRACT FROM AUTHOR]

Highly efficient surface acoustic wave (SAW) transducers offer significant advantages for microfluidic atomization. Aiming at highly efficient atomization, we innovatively accomplish dual-surface simultaneous atomization by strategically positioning the liquid supply outside the IDT aperture edge. Initially, we optimize Lamb wave transducers and specifically investigate their performance based on the ratio of substrate thickness to acoustic wavelength. When this ratio h / λ is approximately 1.25, the electromechanical coupling coefficient of A0-mode Lamb waves can reach around 5.5% for 128° Y-X LiNbO3. We then study the mechanism of droplet atomization with the liquid supply positioned outside the IDT aperture edge. Experimental results demonstrate that optimized Lamb wave transducers exhibit clear dual-surface simultaneous atomization. These transducers provide equivalent amplitude acoustic wave vibrations on both surfaces, causing the liquid thin film to accumulate at the edges of the dual-surface and form a continuous mist. [ABSTRACT FROM AUTHOR]

The processing of pure copper (Cu) has been a challenge for laser-based additive manufacturing for many years since copper powders have a high reflectivity of up to 83% of electromagnetic radiation at a wavelength of 1070 nm. In this study, Cu particles were coated with sub-micrometer tungsten (W) particles to increase the laser beam absorptivity. The coated powders were processed by powder bed fusion-laser beam for metals (PBF-LB/M) with a conventional laser system of <300 watts laser power and a wavelength of 1070 nm. Two different powder manufacturing routes were developed. The first manufacturing route was gas atomization combined with a milling process by a planetary mill. The second manufacturing method was gas atomization with particle co-injection, where a separate W particle jet was sprayed into the atomized Cu jet. As part of the investigations, an extensive characterization of powder and additively manufactured test specimens was carried out. The specimens of Cu/W powders manufactured by the milling process have shown superior results. The laser absorptivity of the Cu/W powder was increased from 22.5% (pure Cu powder) to up to 71.6% for powders with 3 vol% W. In addition, a relative density of test specimens up to 98.2% (optically) and 95.6% (Archimedes) was reached. Furthermore, thermal conductivity was measured by laser flash analysis (LFA) and thermo-optical measurement (TOM). By using eddy current measurement, the electrical conductivity was analyzed. In comparison to the Cu reference, a thermal conductivity of 88.9% and an electrical conductivity of 85.8% were determined. Moreover, the Vickers hardness was measured. The effect of porosity on conductivity properties and hardness was investigated and showed a linear correlation. Finally, a demonstrator was built in which a wall thickness of down to 200 µm was achieved. This demonstrates that the Cu/W composite can be used for heat exchangers, heat sinks, and coils. [ABSTRACT FROM AUTHOR]

Recent studies have increasingly focused on integrating detonation processes into engine technologies, advancing beyond the fundamental research phase of detonation research. The present study investigates the detonability and combustion characteristics of liquid fuels, specifically ethanol, with an emphasis on the effects of atomization properties facilitated by different atomizer designs to implement pulse detonation combustion engines. Oxygen was used as the oxidizer. We employed internal injectors (I45, I90, IB4) and atomizer venturis (VA, VB, VR) to examine how variations in liquid fuel atomization and atomizer configurations influence detonation. The occurrence of detonation was assessed using predicted Sauter mean diameters (SMDs) and exit velocities for different atomizer setups. Additionally, we evaluated the effects of nitrogen dilution at concentrations of 0%, 25%, and 50% on velocity variations and changes in detonation characteristics. The findings suggest that while higher exit velocities decrease SMD, facilitating detonation, excessively high velocities hinder detonation initiation. Conversely, lower exit velocities emphasize the role of SMD in initiating detonation. However, the introduction of nitrogen, which reduces the SMD, was found to decrease reactivity and impede detonation. [ABSTRACT FROM AUTHOR]

The geometry of an orifice is a major determinant of nozzle internal flow and cavitation, which directly govern spray atomization and consequently affect combustion and fuel economy in internal combustion engines. In this study, simulation models of the nozzle at different angles between the normal and the injection hole inlet cross-section and the injection hole axis, as well as with different injection hole cone angles (a positive angle between the injection hole axis and its walls implies a divergent hole), were investigated by means of a previously developed numerical model that was validated based on experimental data from X-ray image technology. The results indicate that as the angle between the normal and the injection hole inlet cross-section and the injection hole axis increases, the cavitation asymmetry within the injection hole intensifies, accompanied by a decrease in the gas volume fraction. On one side of the injection hole, the hydraulic flip width expands, while, on the other side of the injection hole, the flow state gradually changes from hydraulic flip to super-cavitation flow, transitional cavitation and fully reattached flow. The divergent orifice layout intensifies cavitation, and the higher the positive injection hole cone angle, the bigger the hydraulic flip width. The convergent layout of the injection hole suppresses cavitation, and cavitation inside the nozzle disappears completely when the injection hole cone angle is less than −10°. [ABSTRACT FROM AUTHOR]

This study presents an improved comprehensive atomization model for a pressure swirl atomizer. The model integrates internal flow predictions, linear instability analysis of a swirling annular liquid sheet, primary atomization sub-model, and droplet velocity sub-model. Measurement data combined with the inviscid theory model predict the internal flow, providing liquid sheet velocity and thickness at the atomizer outlet. The dispersion relation of surface disturbances is obtained through linear instability analysis. A primary breakup predictive model for particle size distribution is constructed based on the wavelength and growth rate within the full unstable wavenumber range of the dispersion relation. Assuming uniform circumferential distribution and a normal distribution of spray angles, the droplet velocity is assigned according to the liquid sheet velocity. The model is implemented into Eulerian–Lagrangian simulations as initial conditions for discrete phase droplets to simulate the spray field. Results show the model can accurately predict the Sauter mean diameter with an error of less than 6% and effectively predicts the spray structure and spray cone angle. The dependency of the model on its parameters is also studied, determining that the values of the ligament constant and dispersion angle have an obvious impact on the prediction of Sauter mean diameter and spray structure. [ABSTRACT FROM AUTHOR]

Coal mine acid drainage is a type of industrial wastewater generated in the process of coal production and utilization that has a low pH and contains a small amount of organic matter and SO42−, which is harmful to the environment. The ·OH scavenger was used to optimize the grounded electrode atomized corona discharge (GEACD) technology for the treatment of coal mine acidic wastewater. The effects of various factors on the discharge effect were investigated, and the optimal operating scheme for the subsequent test was determined as 35 mm distance between barrel electrodes, 0.6 mm diameter of wire electrodes, and a flow rate of 45 mL/min. The effects of discharge voltage, discharge time, and ·OH scavenger on COD removal rate and pH in coal mine acid drainage were also investigated. The results showed that at the optimum discharge voltage of 12 kV, discharge time of 66 min, and SO42− to ethanol concentration ratio of 1, the COD value decreased from 152.84 mg/L to 43.27 mg/L, and the pH value increased from 5.6 to 6.1. [ABSTRACT FROM AUTHOR]

The encapsulation of β-carotene was investigated using pullulan and whey protein isolate (WPI) as a composite matrix at a weight ratio of 20:80, employing both spray-drying and freeze-drying techniques. The influence of processing parameters such as the concentration of wall material, flow rate, and inlet temperature for SP encapsulants, as well as wall-material concentration for FZ encapsulants, was examined in terms of encapsulation efficiency (EE). The morphology, structural characterization, moisture sorption isotherms, and thermal properties of the resulting encapsulants at optimum conditions were determined. Their stability was investigated under various levels of water activity, temperature conditions, and exposure to UV–Vis irradiation. β-carotene was efficiently encapsulated within SP and FZ structures, resulting in EE of approximately 85% and 70%, respectively. The degradation kinetics of β-carotene in both structures followed a first-order reaction model, with the highest rate constants (0.0128 day−1 for SP and 0.165 day−1 for FZ) occurring at an intermediate water-activity level (aw = 0.53) across all storage temperatures. The photostability tests showed that SP encapsulants extended β-carotene's half-life to 336.02 h, compared with 102.44 h for FZ encapsulants, under UV–Vis irradiation. These findings highlight the potential of SP encapsulants for applications in functional foods, pharmaceuticals, and carotenoid supplements. [ABSTRACT FROM AUTHOR]

An increased demand for natural products nowadays most specifically probiotics (PROs) is evident since it comes in conjunction with beneficial health effects for consumers. In this regard, it is well known that encapsulation could positively affect the PROs' viability throughout food manufacturing and long-term storage. This paper aims to analyze and review various double/multilayer strategies for encapsulation of PROs. Double-layer encapsulation of PROs by electrohydrodynamic atomization or electrospraying technology has been reported along with layer-by-layer assembly and water-in-oil-in-water (W1/O/W2) double emulsions to produce multilayer PROs-loaded carriers. Finally, their applications in food products are presented. The resistance and viability of loaded PROs to mechanical damage, during gastrointestinal transit and shelf life of these trapping systems, are also described. The PROs encapsulation in double- and multiple-layer coatings combined with other technologies can be examined to increase the opportunities for new functional products with amended functionalities opening a novel horizon in food technology. [ABSTRACT FROM AUTHOR]

Detonation engines are gaining prominence as next-generation propulsion systems that can significantly enhance the efficiency of existing engines. This study focuses on developing an injector utilizing liquid fuel and a gas oxidizer for application in detonation engines. In order to better understand the spray characteristics suitable for the pulse detonation engine (PDE) system, an injector was fabricated by varying the Venturi nozzle exit diameter ratio and the geometric features of the fuel injection hole. Analysis of high-speed camera images revealed that the Venturi nozzle exit diameter ratio plays a crucial role in determining the characteristics of air-assist or air-blast atomization. Under the conditions of an exit diameter ratio of Re/Ri = 1.0, the formation of a liquid film at the exit was observed, and it was identified that the film's length is influenced by the geometric characteristics of the fuel injection hole. The effect of the fuel injection hole and Venturi nozzle exit diameter ratio on SMD was analyzed by using droplet diameter measurement. The derived empirical correlation indicates that the atomization mechanism varies depending on the Venturi nozzle exit diameter ratio, and it also affects the distribution of SMD. The characteristics of the proposed injector, its influence on SMD, and its velocity, provide essential groundwork and data for the design of detonation engines employing liquid fuel. [ABSTRACT FROM AUTHOR]

In the present work, novel Al2O3 particles were used to reinforce heterogeneous CoCrFeMnNi high-entropy alloy (HEA) matrix composites with nano- (5.0 wt.%) and nano- + micro- (5.0 wt.% + 10.0 wt.%) specimens. Al2O3 particles were fabricated via gas atomization and spark plasma sintering. The microstructure evolution and properties, i.e., density, hardness, and room temperature compression, were systematically investigated. The results indicate that the concentration of the Cr element in the pure CoCrFeMnNi HEA and the HEA matrix composite can be effectively reduced by using a gas-atomized HEA powder as the matrix. The formation of an impurity phase can also be inhibited, while the distribution uniformity of matrix elements can be improved. The composites prepared via gas-atomized powders formed a network microstructure composed of continuous Al2O3-rich regions and isolated Al2O3-poor regions, exhibiting good plasticity and improved density. The relative densities of the pure HEA, nano- (5.0 wt.%), and nano- + micro- (5.0 wt.% + 10.0 wt.%) composites were 98.9%, 97%, and 94.1%, respectively. The results demonstrate a significant improvement in the relative densities compared to the values (97.2%, 95.7%, and 93.8%) of the composites prepared via mechanical alloying. In addition, compared to the compressive fracture strains of nano- (5.0 wt.%) and nano- + micro- (5.0 wt.% + 10.0 wt.%) composites based on the mechanically alloyed HEA powder, the values of the nano- (5.0 wt.%) and nano- + micro- (5.0 wt.% + 10.0 wt.%) specimens prepared via gas atomization and spark plasma sintering increased by 80% and 67%, respectively. [ABSTRACT FROM AUTHOR]

Aluminum/tetrahydrodicyclopentadiene/oleic acid (Al/JP-10/OA) nanofluid fuel is considered a potential fuel for aircraft powered by aviation turbine engines. However, an optimized formula for an Al/JP-10/OA system inducing a secondary atomization and micro-explosion effect and improving the burning performance needs to be developed. With this aim, in this work, the combustion characteristics of pure JP-10, JP-10/OA, JP-10/Al, and Al/JP-10/OA were experimentally tested, and a comparative analysis was conducted. Specifically, the influence of the surfactant and nanoparticle concentrations on the combustion characteristics of Al/JP-10/OA nanofluid fuel, including the flame structure, the flame temperature, the burning rate, the secondary atomization and micro-explosion effect, etc., were evaluated in detail. The results demonstrate that the addition of OA surfactant and Al nanoparticles had a significant effect on the burning rate of fuel droplets. The OA had an inhibition effect, while the Al nanoparticles had a promotion effect. As both OA and Al nanoparticles were added to the JP-10, the synergetic effect had to be considered. At the optimum ratio of OA to Al for the best suspension stability, there is a critical Al concentration of 1.0 wt.% from promotion to inhibition with increases in the Al concentration. The addition of OA and Al nanoparticles induced the secondary atomization and micro-explosion, resulting in an unsteady combustion and chaotic flame structure. The transient flame temperature of hundreds of Kelvins increased, the high-temperature flame zone widened, and thus, the energy release was elevated. Therefore, the combustion performance and energy release of Al/JP-10/OA nanofluid fuel can be improved through the secondary atomization and micro-explosion effect induced by the surfactant and nanoparticles. [ABSTRACT FROM AUTHOR]

The main objective of this study was to use flash boiling atomization as a new method to inject suspensions with high solid content into the high-power plasma flow. The water-based suspension was prepared with submicron titanium oxide particles with an average size of 500 nm. The investigated solid concentrations were 20, 40, 55 and 70 wt%. Two plasma torches operated at 33, 70 and 110 kW were used to investigate the effect of increasing power on the deposited microstructure and deposition efficiency. At low torch power, the deposition efficiency decreased with increasing solid concentration, and deposits with a high number of unmelted particles were obtained with 70 wt% suspensions. At high torch power, the deposition efficiency increased with increasing solid concentration, and dense deposits were obtained with 70 wt% suspensions. XRD analysis was performed on all deposits to determine the distribution of rutile and anatase phases. The percentage of the anatase phase varied from 35.7% to 66.9%, depending on the power input and solid concentration. [ABSTRACT FROM AUTHOR]

This study is aimed at traditional vegetable grafting using a large number of plastic clips, which cannot be recycled in time and cause serious pollution within the planting environment. This paper proposes a new grafting method based on a UV adhesive instead of plastic clips. First of all, a UV adhesive spray grafting device was designed. The structure includes seedling adsorption positioning mechanisms, a butt joint mechanism, a handling mechanism, a spray valve, a UV curing lamp, etc., to facilitate the adhesive spraying. For the rootstock and scion, a horizontal, lateral seedling and negative pressure adsorption and positioning method is adopted, with fluid dynamics simulation of the diameter and quantity of the adsorption holes in the rootstock adsorption mechanism carried out using Fluent 2022 R1 software and completion of the optimization of the parameters of the adsorption and positioning mechanism. The fluid volume method is used to simulate the adsorption and positioning mechanism. For optimization, the volume of fluid method (VOF) and the discrete particle method (DPM) are used in a coupled simulation of the UV adhesive spraying process, and the value range of the spraying influencing factors is determined: the selected glue pressure, atomization pressure, and spraying height for three-factor, three-level orthogonal simulation. A grafting test is also verification, deriving the significance ranking of their impact on the success rate of the grafting: atomization pressure > spraying height > glue pressure. Under the condition of a 0.25 Mpa atomization pressure, a 0.15 Mpa glue supply pressure, and a 10 mm spraying height, the grafting success rate for watermelon was 100%, the effective spraying rate was 83.03%, the healing success rate was 94.5%, and the length of the film was 7.86 mm. The results of the study can provide a research basis for the research and development of new types of spraying and grafting robot technology. [ABSTRACT FROM AUTHOR]

High-quality Fe-Cr-Ni-W-B spherical powder is crucial for the powder metallurgy preparation of high-strength and tough Fe-Cr-Ni-W-B alloys. In this study, the controlled preparation of high-quality Fe-Cr-Ni-W-B spherical powder was achieved using the vacuum gas atomization method. The effects and mechanisms of atomization gas pressure, the melt nozzle inner diameter, and heat treatment temperature on the microstructure and flowability of Fe-Cr-Ni-W-B spherical powder were systematically investigated. By optimizing process parameters, spherical Fe-Cr-Ni-W-B powder with a sphericity of 95.1% and a flowability of 15.88 s/50 g was obtained, laying the foundation for the powder metallurgy preparation of high-strength and tough Fe-Cr-Ni-W-B alloys. [ABSTRACT FROM AUTHOR]

The process of impinging-jet atomization involves the collision of multiple liquid jets to create atomization. This study specifically focuses on a system that utilizes impinging atomization with multiple jets. The injectors used in this study are arranged in either a planar configuration for doublet injectors or a stereoscopic configuration for quadruplet injectors, both designed to facilitate impinging atomization. The angle at which the jets collide is set at 90°, with injector intersection angles of either 60° or 120°. The diameter of the jets ranges from 0.8 to 1.1 mm, while the length–diameter ratio of the pipe remains fixed at 10. To investigate the atomization process, experiments were conducted by varying flow rates (ranging from 30 to 130 mL/min) from each injector using pure water as the working fluid. This resulted in a range of Weber numbers spanning from 4 to 206 and Reynolds numbers ranging from 578 to 3443. Four atomization regimes were observed in the impinging atomization flow field: closed-rim mode, periodic drop mode, open rim mode, and fully developed mode. The experiment utilized a high-speed camera to observe the formation and breakup of the liquid sheet. However, increasing the number of jets and altering the impingement configuration had minimal impact on the liquid sheet patterns as the Weber number increased. Compared to traditional double jet atomization, quadruplet jet atomization resulted in the wider extension of liquid sheets and similar atomization patterns. This study is useful for designing jet impingement-atomization systems for confined spaces. [ABSTRACT FROM AUTHOR]

(1) Background: Various types of adjuvants are added during application to enhance the spraying effect, but most adjuvant formulations are proprietary products, and their exact compositions have not been disclosed. (2) Methods: The spatial distributions of droplet sizes and velocities generated by the atomization of different polymer adjuvants were measured based on the phase Doppler interferometer (PDI) measurement method. The sub-area statistical method was used to quantitatively analyze the droplet characteristics at various points below the nozzle. (3) Results: The polymer (polyethylene oxide (PEO))/associative surfactant (sodium dodecyl sulfate (SDS)) can increase the droplet size and velocity of the solution after atomization by increasing the amount of the polymer/associative surfactant to reduce the equilibrium surface tension of the solution and increase the viscosity. Different concentrations of polymer/associative surfactant atomization produced larger droplet sizes and better uniformity than polymer/non-associative surfactant (polysorbate-20 (Tween20)). At the same position, the relationship between droplet velocities for the three adjuvant combinations was roughly as follows: PEO/SDS solution had the highest velocity, followed by PEO solution, and PEO/Tween20 solution had the lowest velocity. (4) Conclusions: The optimal of droplet size distribution can be achieved by adding appropriate amounts of associative surfactants to polymers. [ABSTRACT FROM AUTHOR]

Viscosity is a physicochemical property that evaluates the resistance that fuel offers to flow, influencing the engine's operation and combustion process. Its control is aimed at good fuel atomization and the preservation of lubricating characteristics. Changes in viscosity can lead to wear on various parts of the engine. Viscometers typically measure the viscosity of fuels in the oil and gas industry. These instruments can measure the time it takes for a fluid to move a given distance through a pipe or the time it takes for an object of a given size and density to pass through the liquid. The traditional test method, ASTM D445, differentiates the procedure for opaque liquids from transparent ones; that is, it requires a warm-up of the sample between 60 °C and 65 °C for 1 h. This additional step can overload laboratory routines, although it is not guaranteed to have a metrologically significant effect on the final result. Thus, this study evaluated the relevance of complying with this step in the test method for the kinematic viscosity of opaque liquids using a 32 factorial experimental design. Based on the F test, p-value, confidence intervals, and percentage contribution of the sum of squares approaches concerning the regression analysis, one concluded that the warm-up time was not a relevant factor in the kinematic viscosity, specifically of very low sulphur fuel oil, Brazilian fuel oil, and atmospheric residue diluted with diesel oil, which are fluids at room temperature. [ABSTRACT FROM AUTHOR]

Pressure nozzles are widely used in spray drying and other industries. In order to improve the atomization characteristics of pressure cyclone nozzles, a new type of annular jet gas impingement atomization device is developed. We use high-speed imaging and digital image processing and other methods to analyze the spray characteristics of the different annular device configurations (using four, six, and eight tubes) and under different gas–liquid mass flow rates. It is shown that with an increase in the Air–Liquid mass Ratio (ALR), the liquid film breakup process changes from undulating sheet breakup to perforated sheet breakup and the breakup length decreases. The breakup length decreases the most under the condition of six-tube airflow with the range of 31–55%, while the Sauter mean diameter (SMD) basically does not change. With the increase in ALR and the Weber number of liquid (Wel), the droplet size distribution becomes more uniform. The spray characteristics of the atomizer assisted by gas jets reaches the best state when Wel = 4596.3 and m ˙ g = 1.97 g/s. The experimental conclusions have some guiding significance for the design and optimization of the atomization devices in spray drying towers. [ABSTRACT FROM AUTHOR]

Spray drying of oil-in-water emulsions is a widespread encapsulation technique. The oil droplet size (ODS) significantly impacts encapsulation efficiency and other powder properties. The ODS is commonly set to a specific value during homogenization, assuming that it remains unchanged throughout the process, which is often inaccurate. This study investigated the impact of atomizer geometry and nozzle dimensions on oil droplet breakup during atomization using pressure-swirl atomizers. Subject of the investigation were nozzles that differ in the way the liquid is set in motion, as well as different inlet port and outlet orifice dimensions. The results indicate that nozzle inlet port area may have a significant impact on oil droplet breakup, with x90,3 values of the oil droplet size distribution decreasing from 5.29 to 2.30 µm with a decrease of the inlet area from 2.0 to 0.6 mm. Good scalability of the findings from pilot to industrial-scale was shown using larger nozzles. A simplified theoretical model, aiming to predict the ODS as a function of calculated shear rates, showed reasonable agreement to the experimental data for different atomization pressures with coefficients of determination of up to 0.99. However, it was not able to predict the impact of different nozzle dimensions, most likely due to changes in flow characteristics. These results suggest that the stress history of the oil droplets might have a larger influence than expected. Further studies will need to consider other zones of high stress in addition to the outlet orifice. [ABSTRACT FROM AUTHOR]

Innovations in drug delivery systems are crucial for enhancing therapeutic efficiency. Our research presents a novel approach based on using electro-fluid dynamic atomization (EFDA) to fabricate core-shell monophasic particles (CSMp) from sodium alginate blends of varying molecular weights. This study explores the morphological characteristics of these particles in relation to material properties and process conditions, highlighting their potential in drug delivery applications. A key aspect of our work is the development of a mathematical model that simulates the release kinetics of small molecules, specifically sodium diclofenac. By assessing the diffusion properties of different molecules and gel formulations through transport and rheological models, we have created a predictive tool for evaluating the efficiency of these particles in drug delivery. Our findings underscore two critical, independent parameters for optimizing drug release: the external shell thickness and the diffusivity ratios within the dual layers. This allows for precise control over the timing and intensity of the release profile. This study advances our understanding of EFDA in the fabrication of CSMp and offers promising avenues for enhancing drug delivery systems by tailoring release profiles through particle characteristic manipulation. [ABSTRACT FROM AUTHOR]

Improving diesel engine performance requires a comprehensive understanding of fuel atomization and air–fuel mixing within the combustion chamber. Numerous studies have been conducted to reduce emissions and enhance diesel engines. However, further investigation is required on the detailed diesel spray process. In this study, we adopted extinction measurement to analyze the effects of a fuel injection pressure range of 300 to 700 bar on spray morphology. For the extinction imaging setup, we utilized a high-intensity continuous LED source along with a diffuser to ensure uniform light distribution. The high-speed extinction and image processing results indicate that increasing the injection pressure from 300 to 700 bar effectively produced a smaller particulate size (15% reduction) and a better air–fuel mixing process. Especially at the end of injection, our results show smaller liquid ligaments (50% reduction) and droplets around the injector tip with higher injection pressure cases. [ABSTRACT FROM AUTHOR]

This study experimentally explored the effects of equivalence ratio settings on ethanol fuel combustion oscillations with a laboratory-scale combustor. A contrary flame equivalence ratio adjusting trend was selected to investigate the dynamic characteristics of an ethanol atomization burner. Research findings denote that optimizing the equivalence ratio settings can prevent the occurrence of combustion instability in ethanol burners. In the combustion chamber, the sound pressure amplitude increased from 138 Pa to 171 Pa and eventually dropped to 38 Pa, as the equivalence ratio increased from 0.45 to 0.90. However, the sound pressure amplitude increased from 35 Pa to 199 Pa and eventually dropped to 162 Pa, as the equivalence ratio decreased from 0.90 to 0.45. The oscillation frequency of the ethanol atomization burner presents a migration characteristic; this is mainly due to thermal effects associated with changes in the equivalence ratio that increase/decrease the speed of sound in burnt gases, leading to increased/decreased oscillation frequencies. The trend of the change in flame heat release rate is basically like that of sound pressure, but the time-series signal of the flame heat release rate is different from that of sound pressure. It can be concluded that the reversible change in equivalence ratio will bring significant changes to the amplitude of combustion oscillations. At the same time, the macroscopic morphology of the flame will also undergo significant changes. The flame front length decreased from 25 cm to 18 cm, and the flame frontal angle increased from 23 to 42 degrees when the equivalence ratio increased. A strange phenomenon has been observed, which is that there is also sound pressure fluctuation inside the atomized air pipeline, and it presents a special square waveform. This study explored the equivalence ratio adjusting trends on ethanol combustion instability, which will provide the theoretical basis for the design of ethanol atomization burners. [ABSTRACT FROM AUTHOR]

Maintenance is a highly procedural activity requiring motor and cognitive engagement. The aim of this experimental study was to examine how expertise affects maintenance tasks, in particular, the use of procedural documents. A total of 22 aircraft maintenance technicians were divided into two groups according to their level of expertise. Helicopter maintenance was evaluated in a real work environment, using an eye tracker, a fixed camera, and NASA-TLX to measure workload. Both groups reported a high mental load. Novices showed elevated levels of effort and mental demand. Experts were faster at all levels of the task and spent less time consulting maintenance documentation. The acquisition of procedural information was greater at the start of the task, where the gap between groups was more pronounced. This may be related to the overall planning of the task, in addition, the task was atomized, with frequent back-and-forth between execution and information intake, for all participants. Novices had a longer document consultation duration, spread over a greater number of consultations, but did not have a higher average consultation time. The results indicate a higher mental load for novices, potentially linked to an increased atomization of the task, as shown by the frequency of consultations. [ABSTRACT FROM AUTHOR]

The powder bed packing density of metal powders plays a crucial role in additive manufacturing as it directly affects the defect and mechanical properties of the fabricated parts. Powder bed packing density is related to powder flowability and spreadability. In this study, we introduced a new method to improve powder flowability and spreadability, where Haynes 230 powder with exceptional flowability was successfully produced using an in situ micro-oxidation gas atomization process. Compared to conventional gas atomization, the powder exhibited improved flowability and spreadability, measuring at 11.8 s/50 g. Additionally, the angle of repose was reduced by 25%, resulting in a powder bed packing density of 5.67 g/cm3, corresponding to 63.7% of the theoretical density. Notably, the oxygen content in the powder was only 180 ppm, as confirmed by XRD testing, and no oxide peaks were detected. Furthermore, the depth of the oxide layer on the particle surface increased by less than 20 nm. As a result, the in situ micro-oxidation process reduces the number of pores and cracks in the Haynes 230 alloy formed specimens and improves the relative density of the built specimens. This study highlights the potential of in situ micro-oxidation gas atomization as a promising method for producing powders with high flowability and spreadability for laser powder bed fusion (LPBF) processes. [ABSTRACT FROM AUTHOR]

The atomization of liquid spray solutions through nozzles is a mechanism for delivering many pesticides to the target. The smallest drop sizes (<150 μm) are known as driftable fines and have a propensity for wind-induced convection. Many agricultural applications include oil-in-water formulations. The experimental metrics obtained from spray images of these formulations include the distance from the nozzle origin to the drop centroid once a drop has formed; the hole location and surface area for holes that form in the liquid sheet (all hole areas approximated as polygons); the angles formed between polygon segments (whose vertices are represented as boundary points); and the ligament dimensions that form from intersecting holes, such as the ligament aspect ratio (R/L), ligament length (L), and ligament radius (width), along with the number of drops a ligament breaks up into. These metrics were used in a principal component regression (PCR) analysis, and the results illustrated that 99% of the variability in the response variable (DT10) was addressed by 10 principal components. Angles formed by the colliding holes, hole distance from the nozzle, drop distance, hole number, ligament number, and drop number were negatively correlated to the atomization driftable fine fraction, while hole area, ligament distance, ligament area, and boundary area were positively correlated. Thus, to decrease/minimize driftable fines, one needs to increase the negatively correlated metrics. [ABSTRACT FROM AUTHOR]

Insulators, pivotal to the integrity of railway catenaries, demand impeccable functioning to prevent system failures. Their consistent assessment is vital for railway safety. Current insulator evaluations in subways predominantly involve human intervention, a method fraught with inefficiencies, inaccuracies, and oversights, exacerbated by the complex backdrop of subway tunnels and minuscule defect dimensions. This study introduces an enhanced algorithm, anchored in the YOLOv5 framework, to refine insulator defect identification. Challenges in defect detection include limited, imbalanced data samples and adaptability. Addressing this, an accurate catenary model mirrors the subway line's architecture, facilitating the creation of synthetic instances of both intact and impaired insulators. An atomization technique augments the dataset volume, fortifying the algorithm's resilience in reduced visibility conditions, such as fog. Tackling sample equilibrium, the study introduces an equilibrium loss function, assigning disparate weights to various sample categories during training, thereby sharpening the algorithm's focus on positive instances, particularly those that are challenging to discern, and rectifying the disproportion in sample categories. Incorporating lightweight structures like GhostNet and the Efficient Channel Attention Network (ECA-Net) channel attention scheme not only diminishes the network's computational demands, thereby elevating the detection capabilities, but also minimizes superfluous data processing, enhancing the accuracy in identifying smaller targets. Empirical analyses indicate substantial model optimization: a size reduction to 60 pp of its original (from 15 MB to 9 MB), a near 1.4 pp increase in mean average precision (mAP) to 96.57%, and a tripling of the detection speed (from 30 to 90 FPS). Real-world image assessments further reveal a mAP improvement of approximately 2.5 pp (reaching 98.43%), confirming the model's suitability for real-time applications. [ABSTRACT FROM AUTHOR]

In the combustion chamber of scramjets, fuel jets interact with supersonic airflow in the form of a liquid jet in crossflow (LJIC). It is difficult to achieve adequate jet–crossflow mixing and the efficient combustion of fuel in an instant. Large eddy simulation (LES), the coupled level-set and volume of fluid (CLSVOF) method, and an adaptive mesh refinement (AMR) framework are used to simulate supersonic LJICs in this article. This way, LJIC atomization characteristics and mechanisms can be further explored and analyzed in detail. It is found that the surface waves of the liquid column exist in a two-dimensional form, including vertical and spanwise directions. Column breakup occurs when all the spanwise surface waves between adjacent vertical surface waves break up. Bow shock waves, composed of multiple connected arcuate shock waves, are dynamic and will change with the evolution of the liquid column. The vortex ring movement of supersonic LJICs, whose trends in the vertical and spanwise directions are different, is relatively complex, which is due to the complex and time-dependent shape of liquid columns. [ABSTRACT FROM AUTHOR]

Cocoa honey, a by-product obtained during the processing of cocoa, is a juice rich in pectin, organic acids, minerals and phenolic compounds with antioxidant properties. Fresh cocoa honey is quickly fermented due to its high content of reducing sugars, such as fructose and glucose, which limits its shelf life. Currently, cocoa honey is only commercialized in frozen form, as logistical challenges prevent the wide distribution or export of this by-product for applications in the market of sweets, jellies, beverages, confectionery, and nutraceutical foods among others. Spray-drying technology is a viable prospect for the large-scale stabilization of products such as cocoa honey, with less heat exposure compared to other conventional drying methods. This work aimed to evaluate the efficacy of drying adjuvants for a rapid removal of the water present in cocoa honey via atomization, since this process minimizes the effects of glass transition temperature (Tg) related to materials with high sugar contents. Physical parameters such as the moisture content, hygroscopicity, particle size, and yield of the products obtained were determined. Cocoa honey presented 85.3 ± 0.20 g/100 g of moisture. The formulations successfully decreased moisture content, which was lower than 11.72 ± 0.08 g/100 g in the formulations. Water activity ranged between 0.1464 ± 0.0043 and 0.1562 ± 0.029, with no significant difference between the formulations. The hygroscopicity of cocoa honey powders ranged from 29.29 to 29.87 g of water/100 g of cocoa honey. The combination of 20% maltodextrin and 1% whey protein isolate (WPI) led to the best yield, resulting in a free-flowing powder as the final product. On the other hand, the formulation composed of maltodextrin and whey protein isolate in the ratio of 29:1, respectively, led to the most stable product, with less loss of phenolic compounds during the drying process (6.04%). Regarding particle diameter, 90% of the accumulated distribution did not exceed 57 μm. The greatest dispersion of particles occurs in the Ma20W10 formulation with a span of 2.72, inferring greater variation in size between small (7.01 ± 0.06 μm), medium (18.25 ± 0.37 μm), and large (56.65 ± 1.17 μm) particles. The use of whey protein isolate as an adjuvant proved to be an efficient drying process in the production of cocoa honey powder, and was also advantageous for enriching the nutritional content of the final product due to its protein origin. Furthermore, the combination of spray-drying technology and the use of whey protein isolate as adjuvant led to a free-flowing cocoa honey powder with an adequate particle size and benefits in terms of shelf-life extension, providing new opportunities for the commercialization of cocoa honey as an ingredient for the food industry, with benefits for the circular economy. [ABSTRACT FROM AUTHOR]

(1) Background: Postdural puncture headache (PDPH) remains a serious complication in obstetric patients. While the epidural blood patch represents the current gold standard in therapy, a growing number of alternative measures are thought to be beneficial for clinical management. The purpose of this study was to retrospectively analyze the efficacy of intranasal lidocaine administration to treat PDPH in obstetrics at our university hospital; (2) Methods: A retrospective analysis of the medical records of patients with PDPH has been performed focusing on the techniques of administration, dosing, treatment duration, impact on pain intensity as well as side effects of intranasal lidocaine; (3) Results: During the study period, 5610 obstetric patients received neuraxial anesthesia, of whom 43 (0.77%) developed PDPH. About one third of the patients with PDPH after spinal anesthesia (n = 8), epidural anesthesia (n = 5) or both (n = 2) were treated with intranasal lidocaine. Lidocaine was administered either via gauze compresses (GC, n = 4), a mucosal atomization device (MAD, n = 8) or with a second-line mucosal atomization device due to low gauze compress efficacy (n = 3). All patients treated with lidocaine refused the epidural blood patch. Nebulization of lidocaine resulted in a significant reduction in pain intensity after the first dose (p = 0.008). No relevant side effects developed except sporadic temporal pharyngeal numbness. The utilization of the mucosal atomization device averted the necessity for an epidural blood patch, whether employed as the primary or secondary approach; (4) Conclusions: Our data imply that the mucosal atomization device enhances the efficacy of intranasal lidocaine administration in obstetric patients suffering from PDPH. [ABSTRACT FROM AUTHOR]

Featured Application: The acoustic-hydraulic nozzle can be used in technological tasks where both high droplet dispersion and high productivity in creating an aerosol flow are required. Spray technology is widely used in various industries, including medicine, food production, mechanical engineering, and nanopowder manufacturing. Achieving high dispersion and a narrow particle size distribution is crucial for many applications. Ultrasonic spraying is commonly used to achieve this. On the other hand, hydraulic nozzles provide high atomization performance. Combining these two technologies promises to offer significant benefits, but the complex processes that occur simultaneously in such a device require careful study. This work proposes a fundamental design for an acoustic-hydraulic nozzle and investigates the physical processes when a liquid is sprayed using this nozzle, both theoretically and experimentally. The study identifies the critical modes of spraying and confirms that the simultaneous use of ultrasound and hydraulic pressure can produce a fine spray (droplet size less than 50 μm vs. 150–500 μm for hydrodynamic spray) with high productivity (5–10 mL/s vs. 0.5 mL/min for ultrasonic spray). This approach has significant potential for modern industries and technologies. [ABSTRACT FROM AUTHOR]

To prevent the potential failure of the surface acoustic wave (SAW) atomizer caused by the concentration of thermal stresses, this study investigates the thermal elevation process inherent to the operation of the surface wave atomizer. Subsequently, a method for temperature regulation is proposed. By collecting the temperature rise data of SAW atomizers with water, olive oil, and glycerol at 5/6/7 Watts (W) of power, the temperature curves of the atomizer surface under different conditions are obtained, and the stress changes in the working process are simulated additionally. The results indicate that although the stress generated by surface acoustic wave atomizers varies for different media, there is always a problem of rapid heating during the initial working stage in all cases. To address the above issues, this study analyzed the time when the maximum stress occurred and proposed control methods based on experimental data. The simulation results show that by controlling the driving power within 4 s after the start of atomization, the problem of excessive stress during the heating stage can be avoided. Finally, the feasibility of the control method was verified through a simple power control method (limiting the driving power to 3 W in the first 2 s), proving that this method can effectively reduce the thermal stress during the working process of the atomizer and prevent the atomizer from cracking. [ABSTRACT FROM AUTHOR]

The iron nitride materials, especially α″-Fe16N2, are considered one of the most promising candidates for future rare-earth-free magnets. However, the mass production of α″-Fe16N2 powders as a raw material for permanent magnets is still challenging. In this work, starting from iron lumps as a raw material, we have managed to prepare the α″-Fe16N2 powders via the gas atomization method, followed by subsequent nitriding in an ammonia–hydrogen gas mixture stream. The particle size was controlled by changing the gas atomization preparation conditions. X-ray diffractograms (XRD) analyses show that the prepared powders are composed of α″-Fe16N2 and α-Fe phases. The α″-Fe16N2 volume ratio increases with decreasing powder size and increasing nitriding time, reaching a maximum of 57% α″-Fe16N2 phase in powders with size below 32 ± 3 μm after 96 h nitridation. The saturation magnetization reaches the value of 237 emu/g and a reasonable coercivity value of 884 Oe. Compared to the saturation magnetization values of α-Fe powders, the α″-Fe16N2 powders prepared through our proposed approach show an increase of up to 10% in saturation and demonstrate the possibility of mass production of α″-Fe16N2 powders as precursors of permanent magnets without rare earths. [ABSTRACT FROM AUTHOR]

There is growing interest in the use of micro-sized hydrogels, including bioactive signals, as efficient platforms for tissue regeneration because they are able to mimic cell niche structure and selected functionalities. Herein, it is proposed to optimize bioactive composite microgels via electrohydrodynamic atomization (EHDA) to regenerate the dentin–pulp complex. The addition of disodium phosphate (Na2HPO4) salts as mineral precursors triggered an in situ reaction with divalent ions in solution, thus promoting the encapsulation of different amounts of apatite-like phases. Morphological analysis via image analysis of optical images confirmed a narrow distribution of perfectly rounded particles, with an average diameter ranging from 223 ± 18 μm to 502 ± 64 μm as a function of mineral content and process parameters used. FTIR, TEM, and EDAX analyses confirmed the formation of calcium phosphates with a characteristic Ca/P ratio close to 1.67 and a needle-like crystal shape. In vitro studies—using dental pulp stem cells (DPSCs) in crown sections of natural teeth slices—showed an increase in cell viability until 14 days, recording a decay of proliferation at 21 days, independent on the mineral amount, suggesting that differentiation is started, as confirmed by the increase of ALP activity at 14 days. In this view, mineralized microgels could be successfully used to support in vitro osteogenesis, working as an interesting model to study dental tissue regeneration. [ABSTRACT FROM AUTHOR]

α″-Fe16N2 materials are of increasing interest for their applications in products such as rare earth-free permanent magnets. The lack of a method of mass production for powders as raw materials delays the preparation of such magnets. Through employing the gas atomization method, we managed to prepare α″-Fe16N2 powders whose morphology and magnetic properties were tailored by the preparation parameters. As a result of optimizing the preparation parameters (ejection temperature and pressure, ejection nozzle diameter, and atomization pressure), we managed to prepare powders with a size of about 30 μm and a content of 31% α″-Fe16N2 phase. The value of the saturation magnetization (234.8 emu/g), the reasonable coercivity value (970 Oe) presented by the prepared powders, and the opportunity of scaling up approaches based on the preparation of powders via gas atomization support the feasibility of preparing α″-Fe16N2 powders at an industrial level. [ABSTRACT FROM AUTHOR]

With the increasing demand for efficient and accurate numerical simulations of spray combustion in jet engines, the necessity for robust models to enhance the capabilities of spray models has become imperative. Existing approaches often rely on ad hoc determinations or simplifications, resulting in information loss and potentially inaccurate predictions for critical spray characteristics, such as droplet diameters, velocities, and positions, especially under extreme operating conditions or temporal fluctuations. In this study, we introduce a novel approach to modeling multivariate spray characteristics using Gaussian mixture models (GMM). By applying this approach to spray data obtained from numerical simulations of the primary atomization in air-blast atomizers, we demonstrate that GMMs effectively capture the spray characteristics across a wide range of operating conditions. Importantly, our investigation reveals that GMMs can handle complex non-linear dependencies by increasing the number of components, thereby enabling the modeling of more complex spray statistics. This adaptability makes GMMs a versatile tool for accurately representing spray characteristics even under extreme operating conditions. The presented approach holds promise for enhancing the accuracy of spray combustion modeling, offering an improved injection model that accurately captures the underlying droplet distribution. Additionally, GMMs can serve as a foundation for constructing meta models, striking a balance between the efficiency of low-order approaches and the accuracy of high-fidelity simulations. [ABSTRACT FROM AUTHOR]

A wide range of recent applications require high-quality sprays that are characterized by extremely small-sized droplets, a narrow droplet size distribution, and a short breakup length. Fuel injection systems in propulsion units, energy storage, medical implementations, printings, and coatings are just a few examples. Flash-boiling atomization is a unique method that was extensively developed during the past two to three decades and has been proven to generate high-quality demanded sprays. In flash-boiling atomization, the liquid is forced to reach a metastable superheated state by either rapid heating or rapid pressure drop, where vapor bubbles nucleate, become fast-growing, and subsequently break down the liquid into a fine spray in a very short time. This present article focuses on flash-boiling atomization via rapid depressurization, which is presently more relevant to energy systems. The field of flash-boiling atomization has seen rapid growth and popularity in the past two decades. The aim of this article is to quantitatively portray the landscape and evolutionary trajectory of flash-boiling atomization research and applications and to detect new research frontiers and emerging trends in the literature on flash-boiling atomization. We briefly review the basic theories of the flash-boiling atomization mechanism present a comprehensive overview of the field, from its birth in approximately the 1970s to the present, and provide a database comprising 386 articles published on the topic of flash-boiling atomization. We visualize the intellectual structure of flash-boiling atomization research and applications and track its evolvement over the past five decades, thus providing a global overview and a comprehensive understanding of the development of flash-boiling atomization research and emerging applications. [ABSTRACT FROM AUTHOR]

During variable-rate spraying in orchards, the atomization characteristics and distribution of droplets in and out of the target area can be affected by the sprayer pressure. In this study, a variable-rate spraying control system test bench was designed, and a hollow cone nozzle QY82.317.22 was selected. The droplet atomization characteristics, including volume median diameter (Dv0.5), the relative span of the droplet spectrum, and droplet velocity at different spray pressures, were studied at distances ranging from 0.4 to 2.4 m from the nozzle orifice with an air velocity of 10 m/s at the nozzle orifice position. The effects of longitudinal distance, transverse distance, and spray pressure on Dv0.5, relative span, and droplet velocity were analysed by multiple linear regression analysis, and the regression model was established. The experimental results show that at a longitudinal distance of 1.8 m, Dv0.5 ranges from 120 to 150 μm, meeting the requirements for optimal droplet size for controlling crawling pests and plant diseases on crop leaves; and the relative span is 1.2, indicating a wide droplet spectrum. At different pressure conditions, Dv0.5 decreases as pressure increases. Through multiple linear regression analysis, the longitudinal distance, the transverse distance, and the spray pressure have high significance for Dv0.5 and the droplet velocity. The longitudinal distance and the transverse distance have a highly significant effect on the relative span. In this study, the mathematical relational model of droplet characteristics at different spatial positions and different pressures was established, providing an agricultural reference for predicting the droplet characteristics at different spatial positions to achieve the best application effect. This model is conducive to the effective use of pesticides and reduces environmental pollution. [ABSTRACT FROM AUTHOR]