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We study alchemical atomic energy partitioning as a method to estimate atomization energies from atomic contributions, which are defined in physically rigorous and general ways through the use of the uniform electron gas as a joint reference. We analyze quantitatively the relation between atomic energies and their local environment using a dataset of 1325 organic molecules. The atomic energies are transferable across various molecules, enabling the prediction of atomization energies with a mean absolute error of 23 kcal/mol, comparable to simple statistical estimates but potentially more robust given their grounding in the physics-based decomposition scheme. A comparative analysis with other decomposition methods highlights its sensitivity to electrostatic variations, underlining its potential as a representation of the environment as well as in studying processes like diffusion in solids characterized by significant electrostatic shifts. [ABSTRACT FROM AUTHOR]

Four-center two-electron Coulomb integrals routinely appear in electronic structure algorithms. The resolution-of-the-identity (RI) is a popular technique to reduce the computational cost for the numerical evaluation of these integrals in localized basis-sets codes. Recently, Duchemin and Blase proposed a separable RI scheme [J. Chem. Phys. 150, 174120 (2019)], which preserves the accuracy of the standard global RI method with the Coulomb metric and permits the formulation of cubic-scaling random phase approximation (RPA) and GW approaches. Here, we present the implementation of a separable RI scheme within an all-electron numeric atom-centered orbital framework. We present comprehensive benchmark results using the Thiel and the GW100 test set. Our benchmarks include atomization energies from Hartree–Fock, second-order Møller–Plesset (MP2), coupled-cluster singles and doubles, RPA, and renormalized second-order perturbation theory, as well as quasiparticle energies from GW. We found that the separable RI approach reproduces RI-free HF calculations within 9 meV and MP2 calculations within 1 meV. We have confirmed that the separable RI error is independent of the system size by including disordered carbon clusters up to 116 atoms in our benchmarks. [ABSTRACT FROM AUTHOR]

This article investigates the atomization characteristics of a streamlined direct‐injection atomizer, which finishes the atomization process by coupling the air swirl with the conventional direct injector. First, we used experimental methods to focus on controlling its structural parameters and the liquid‐to‐gas flow ratio. We used a phase Doppler interferometer to measure the Sauter mean diameter (SMD) of the droplets and used a high‐speed camera to capture the atomization field images. The experimental results showed that, under all test conditions, the overall range of the SMD was from 84 to 100 μm. It was found that a higher liquid‐to‐gas flow ratio resulted in a smaller SMD, a larger distance between the liquid and air outlets led to a larger SMD, and an increase in the axial angle of the liquid jet led to a smaller SMD. We found the influence parameters of the atomization characteristics of the streamlined direct‐injection atomizer based on the dimensional analysis, namely, π theorem. In addition, a calculation formula for the SMD was proposed, with multiple linear regression conducted on the sample data from experiment. Based on the findings of this study, the streamlined direct‐injection atomizer can be used to dynamically control its spray characteristics according to the requirements of aviation engine combustion chambers. [ABSTRACT FROM AUTHOR]

AbstractUltrasonic atomization, a powerful method using high-frequency sound waves, has gained notable significance across diverse industries due to its capacity to disintegrate liquids into very fine droplets. The use of ultrasonic vibrations for spray formation can effectively address the challenges associated with conventional methods, including the requirement for high temperatures and high-pressure fluids. Compared to conventional methods, ultrasonic atomizers can deliver a spray with lower velocity, operate at lower temperatures, produce smaller particle sizes, achieve high evaporation rates, and impose low mechanical stress. The radial jet reattachment (RJR) nozzle is a unique design to modify a jet’s flow and improve its transport characteristics, especially in air drying and cooling processes. In this paper, a novel technology is utilized with the combination of an RJR nozzle and ultrasonic atomization to atomize most liquids. The corresponding atomization rate, mist droplet size distribution, and mist droplet velocity distribution, influenced by liquid properties, temperature change, transducer mesh pore size, and applied voltage have been investigated in this paper. The energy consumption ratios, defined as the ratio of thermal energy required to evaporate liquid divided by ultrasonic energy, are analyzed based on atomization rate and applied power, showing very promising results among atomizing methods. Furthermore, the results in terms of the droplet average diameter and mean velocity as well as the resultant volumetric flow rate under different operating conditions and for all working fluids considered have been correlated with the aid of non-dimensional parameters. In addition, certain potential applications based on the remarkable characteristics of the ultrasonic-assisted RJR atomizer such as misting liquids and spray drying are highlighted. [ABSTRACT FROM AUTHOR]

To further improve the dust removal efficiency of water spray, the influence of key structure parameters of nozzle on atomization characteristic (droplet size, atomization angle, flow rate, effective spray distance, wind disturbance resistance) was studied. The results showed that the nozzle had good atomization performance when the outlet diameter was 1.5 mm. The internal structure of the nozzle had an obvious influence on the atomization characteristics. The shrinkage angle had a prominent effect on the droplet size and atomization angle. When the shrinkage angle was increased from 60 to 120°, the droplet size and atomization angle were improved by 29.2% and 45.5%, respectively, while the increased shrinkage angle from 120 to 150° only improved by 9.1% and 4.2%, respectively. In addition, the diameter of the center hole had a strong correlation with the effective spray distance. When the diameter of the center hole increased from 1 to 2 mm, the effective spray distance increased by 60.9% (to 7.4 m) at the pressure of 4 MPa, while the effective spray distance without change increased when the diameter of the center hole increased from 2 to 2.5 mm. It was determined that the nozzle with the outlet aperture of 1.5 mm, the shrinkage angle of 120°, and the diameter of the center hole of 2 mm had good atomization and dust control characteristics. Additionally, it was verified that the optimized nozzle had a substantial improvement in controlling respirable dust, and the dust removal efficiencies for PM2.5 and PM5 were increased by 14.29% and 16.52%, respectively, compared to the original nozzle. This study provided guidance for choosing the nozzle of hydraulic support to form the effective dust control spray. [ABSTRACT FROM AUTHOR]

Based on the finding that the atomization performance of the nozzle is affected by its structural parameters, a combination of finite element analysis and structural optimization calculations is used. Finite element analysis was performed through the VOF (Volume of Fluid) module of Fluent software to determine the structural parameters affecting the performance of the atomizing nozzle. The liquid cyclone tank inclination, the length of the flat section at the gas outlet, and the mixing chamber outlet diameter were used as optimization factors. The atomization cone angle and fuel atomization circumferential distribution uniformity index were used as the evaluation indexes of atomization performance. An orthogonal experimental design was carried out based on the above. Proxy model for atomization cone angle and fuel atomization circumferential distribution uniformity index based on response surface method. The optimal structure of the nozzle was obtained by optimization calculation of the agent model by genetic algorithm. The results show that the atomization performance is optimal when the inclination angle of the liquid rotating tank is 42.9, the length of the flat section at the gas outlet is 3.3, and the diameter of the mixing chamber outlet is 5.0. The atomization cone angle increased by 23.07 % compared with the original model, and the fuel atomization circumferential distribution uniformity index decreased by 45.06 %. A new solution for the design of externally mixed air atomizing nozzles is provided. [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]

Using direct numerical simulation, the primary atomization of shear-thinning liquid jets into stagnant gas is investigated. Starting from a Newtonian configuration with material properties approximately corresponding to a Diesel injection, two hypothetical shear-thinning cases using the power-law and the Carreau-Yasuda models for the calculation of the apparent viscosity are investigated. A recently developed tracking algorithm is used to identify droplets newly formed from the core jet, as well as all other droplets in the computational domain, and a number of relevant droplet characteristics, such as droplet volume, surface area and center of mass, is recorded at each time step. This allows a comparison of droplet characteristics on the basis of probability density functions. It is observed that the shear-thinning behavior of the liquid phase, which is particularly relevant at the interface, influences the droplet volumes and shapes. While the mean viscosity differs significantly for the different cases, the first- and second-order velocity and volume fraction statistics remain nearly unchanged. [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 paper presents experimental findings on the atomization characteristics of coal–water slurries with and without petrochemicals. The fuels were based on flame coal filter cake (slime), which is a typical coal processing waste, flame coal of different particle sizes, wood biomass (sawdust), used transformer oil, and water. The atomized flow characteristics—droplet size and velocity as well as jet angle—were found to depend on the atomizer dimensions and slurry rheology. The experimental data were used to calculate the slurry atomization efficiency factor. The findings were generalized to provide a mathematical description of how the slurry composition and atomizer geometry affect the slurry atomization behavior. Approximations were obtained for atomization characteristics that can be used to predict the jet angle as well as droplet radii and velocities. The developed mathematical tool can be employed to calculate the spraying characteristics when using devices like external-mix twin-fluid atomizers. The approach proposed for data generalization can be applied to adapt the set of approximation equations to other types of nozzles. [ABSTRACT FROM AUTHOR]

Optical laser spray investigations have minimally intrusive, simultaneous measurement capabilities with higher spatial and temporal resolution. The microscopic and macroscopic spray parameters of diesel and diesel-diethyl ether blend spray with a split injection strategy were investigated in this experimental study. Lower effective fuel injection pressure due to lower needle lift under the split injection strategy was responsible for the larger droplet sizes in split injection. However, appropriate closing and opening of the injector for a longer dwell time resulted in diluted spray and finer droplet formation. Longer dwell time provided sufficient time for efficient evaporation of fuel droplets, resulting in higher vapor formation. The liquid fuel fraction was lower for longer dwell time and diesel-diethyl ether spray, indicating superior atomization and evaporation characteristics. Higher fuel injection pressure resulted in longer liquid penetration, which can be reduced by using split injection strategies. Diesel-diethyl ether spray was more diluted for fuel concentration and had a lower spray area than diesel. Two high-velocity peaks were observed for split injections. The occurrence of high-velocity peaks improves the fuel–air mixing and droplet vaporization. Diesel-diethyl ether spray showed a higher density of detection of coarser droplets, indicating evaporation of finer droplets. Higher vapor pressure of diethyl ether resulted in rapid evaporation of finer droplets. [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]

Background: The lack of visual dynamic spray characterization has made the understanding of the physical processes governing atomization and drug particle formation difficult. This study aimed to investigate the changes in the spray plume morphology and aerodynamic particle size of solution-based pressurized metered-dose inhalers (pMDIs) under different conditions to achieve better drug deposition. Methods: Solution-based pMDIs were studied, and the effects of various factors, such as propellant concentration, orifice diameters, and atomization chamber volume, on drug deposition were examined by analyzing the characteristics of spray plume and aerodynamic particle size. Results: Reducing the actuator orifice and spray area led to a concentrated spray plume and increased duration and speed. Moreover, the aerodynamic particle sizes D50 and D90 decreased, whereas D10 remained relatively unchanged. Decreasing the atomization chamber volume of the actuator led to reduced spray area and an increased duration but a decreased plume velocity. D90 exhibited a decreasing trend, whereas D10 and D50 remained relatively unchanged. Reducing the propellant concentration in the prescription, the spray area and the plume velocity first decreased and then increased. The duration initially increased and then decreased. The values of D50 and D90 showed an initial decreasing followed by an increasing trend, whereas D10 remained relatively unchanged. Conclusions: During the development process, attention should be paid to the changes in the spray area, spray angle, duration, and speed of the spray plume. This study recommended analyzing the characteristics of the spray plume and combining the data of two or more aerodynamic particle size detection methods to verify the deposition in vitro to achieve rapid screening and obtain high lung deposition in vivo. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Drainage & Irrigation Machinery Engineering / Paiguan Jixie Gongcheng Xuebao is the property of Editorial Department of Drainage & Irrigation Machinery Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aerodynamic breakup refers to the process where large droplets are fragmented into small droplets by the aerodynamic force in airflow, which plays a vital role in fluid atomization and spray applications. Previous research has primarily concentrated on the aerodynamic breakup of single‐component droplets, but investigations into the breakup of emulsion droplets are limited. This study experimentally investigated the aerodynamic breakup of water‐in‐oil emulsions in airflow, utilizing high‐speed photography to observe the breakup process and digital in‐line holography to measure fragment sizes. Comparative analyses between emulsion droplets and single‐component droplets are conducted to examine the breakup morphology, breakup regime, deformation characteristics, and fragment size distributions. The emulsion droplets exhibit higher apparent viscosity and shorter stretching lengths of the bag film and peripheral rim due to the presence of a dispersed phase. The breakup regime transitions of emulsions are modeled by integrating the viscosity model of emulsions and the transition model of the pure fluid. The fragment sizes of emulsion droplets are larger due to the shorter lengths of the bag film and peripheral rim. [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]

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]

Particulate matter from coal and stone operations is a primary air pollution source. The traditional nozzle requires high-pressure conditions, and the atomization droplets are large and uneven. This paper aims to study a linear Laval nozzle and investigate the impact of water pressure on atomization performance. The volume of fluid (VOF) model and discrete phase model (DPM) of Fluent are used to simulate the internal and external fields of the nozzle and analyze the velocity, droplet size, and atomization angle. The results show that the optimized water pressure parameters are 0.1 MPa with an air pressure of 0.5 MPa. Droplets in the middle are smaller, while those on the sides are larger. Compared to traditional nozzles, the water pressure is reduced by over 90%, and the Sauter mean diameter (SMD) decreases by over 50%. Moreover, the theoretical spray angle increases by approximately 150%. [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]

Copyright of Light Industry Machinery is the property of Light Industry Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Adjuvants are included in many pesticide spray mixtures to enhance the performance of the applied chemical. Many adjuvants which modify the emulsion or extensional viscosity of the tank‐mixture have been found to offer benefits in drift management, primarily by eliminating or reducing the 'Fine' droplets included in the spray with diameters <100–200 μm that can move off‐target in unfavorable conditions during ground, airblast and aerial pesticide applications. Among wind tunnel and field studies conducted around the world, there is consensus that while some adjuvants are effective for drift management, the performance varies on a case‐by‐case basis, requiring verification for each adjuvant which could be achieved through a programme such as certification based on showing a reduction in Fine droplets and/or a reduction in airborne drift. These can be measured in wind tunnel studies according to international standards. This article provides a review of the current science in this subject area, from the approaches to data collection to a review of existing data and regulatory application for encouraging and rewarding the use of appropriate adjuvants that have been demonstrated to reduce airborne spray drift potential and therefore the size of no‐spray buffer zones appropriate to protect nontarget sensitive areas from drift exposure. Some adjuvants can offer the same reduction in drift as offered by hooded sprayer retrofits. A drift reduction programme based on adjuvant use could include testing candidate adjuvants for their effect on droplet size and reduction in Fine droplets when sprayed through reference nozzles and compared against sprays without the adjuvant. Testing could also be based alternatively on measurements of drift potential on collectors such as monofilament line in wind tunnel or field studies. Once shown to be effective in reducing 'Fines' or spray drift, adjuvants could be certified and then referenced on pesticide labels and/or regulatory or best management practice schemes to encourage their use and offer reductions in use restrictions or no‐spray buffer zone sizes based on drift management. Studies have shown that some adjuvants can reduce pesticide leaching into soils and contamination of groundwater, as well as runoff of active ingredients from plants into the environment. Performance depends on the adjuvant type, the pesticide with which it is used, the soil or plant type, the timing and mass of water input from rainfall and climatic factors. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The purpose of this paper was to study in vitro atomization properties of the self-developed sodium sivelestat for inhalation, evaluate the feasibility of this preparation as an aerosol inhalation, and provide the guidance for the following animal administration experiment. Firstly, in order to ensure accurate, uniform and stable doses of the self-developed product after administration, its atomization performance was analyzed through the testing of fine particle mass and the total emitted dose, and the results of its atomization parameters meet the requirement of inhalation. Next, Atomization characteristics of two commonly used nebulizers, air compressed nebulizer and mesh nebulizer, were studied and compared. The results showed that mesh atomizers have a smaller and more uniform particle size distribution. And then, the experiment of acute lung injury induced by aerosol inhalation of lipopolysaccharide in mice was used to test the therapeutic effect of our self-developed formulation, and compared with the positive control (sodium sivelestat for injection). The results showed that inhalation had a lower concentration and was equally effective than injection of sodium sivelestat. All the results support that the self-developed sodium sivelestat can be used as an aerosol inhaled drug. [ABSTRACT FROM AUTHOR]

Liquid steel atomization using close‐coupled nozzles is highly dependent on the relationship between momentum flux ratio, gas–liquid ratio, aspiration pressure, and operating pressure of inert gases. A strong correlation between these parameters and the final powder must be assumed. Understanding these parameters, their influence on the process, and their interactions with each other is indispensable for efficient powder production. In particular, the industrial application of close‐coupled atomization nozzles, which develop a thin pre‐film on the nozzle tip, is not yet fully understood. A model experiment is presented to investigate interactions between the flow conditions of the gaseous and liquid phases, focusing on recirculation phenomena inside the atomization zone. The experiments show the influence of liquid and gas flow conditions on the spray geometry and the liquid core length, as well as the strong dependence of the liquid mass flux on the gas flow. The aspiration pressure below the liquid nozzle is sensitive to gas pressure and has a major influence on the development of the liquid core and the pre‐film, as it increases the liquid mass flux. For practical application, the results confirm an optimal operating point of interacting system parameters, which leads to high‐quality atomization with minimal use of resources. [ABSTRACT FROM AUTHOR]

In the present work, the calibration dependencies for the M062X (i=1),B3LYP (i=2), wB97XD (i=3), M08HX (i=4), MN15 (i=5), G3B3 (i=6) and CBS‐QB3 (i=7) and several other modeling approaches are determined using the calculated values of ΔraHo of atomization and literature based values of ΔraHo(X,TAB) of 14 reference peroxides. These calibration dependencies are used for the determination of ΔraHo(X,CORRP)i and ΔfHo(X,CORRP)i of other peroxides. The coordination of values of ΔfHo(X,CORRP)i (i=1–7) by the intersection of their 3σPi intervals is used for the determination of the most consistent values of ΔfHo(X,MEANP). These values of ΔfHo(X,MEANP) are used for the determination of BDE of peroxides. It's demonstrated that the calculated and literature values of BDE are in agreement. Among the considered modeling approaches, the lowest uncertainties (σPi) are determined for the G3B3 (3.1 kJ/mol), CBS‐QB3 (4.1 kJ/mol), and M062X/6‐311++G(d,p) (6.1 kJ/mol) approaches. [ABSTRACT FROM AUTHOR]

The liquid is discharged into the surrounding atmospheric environment through the nozzle or orifice with small inner diameter. When the outlet pressure or flow is increased, the flow mode of the liquid at the end of the capillary can change from periodic dripping (PD) to dripping faucet (DF) with latter jetting (J). Through changing the flow rate, three typical atomization modes of PD, DF and J for deionized water and ethanol were recorded by high-speed digital camera, and the critical Weber number of the transition of atomization mode was obtained. The results show that in the process of PD, the shape of droplets is gradually changed from spherical to pear-shape with the increasing of outer diameter of the orifice. As the flowrate is increased, two liquids are gradually reached the jetting regime from the dripping mode through the dripping faucet. Compared with deionized water, the transition of ethanol exists in small range and only in the inner diameter of 0.33-0.60 mm, and it is very easy to transition directly from periodic dripping to jetting regime. The difference of atomization mode transition between deionized water and absolute ethanol is caused by the different surface tension. The critical Weber number corresponding to the transition from dripping to jetting mode can realize the prediction of the atomization mode transition process. [ABSTRACT FROM AUTHOR]

The phenomenon of the burnt degree of the coil（cotton wick)has a serious impact on consumer health and experience. Sweeteners are an important component of e-liquids, but Neotame is the only option for sweetener in e-liquids listed in the Chinese national standard. There still lacks systematic and comparative report on sweeteners, and it’s hard to directly evaluate the effect of sweetener on the burnt degree of the coil(cotton wick). The sensory evaluation on the sweetness characteristics of glucose-stevioside(GSG), rubusoside, sucralose, Neotame, Fulltame（FA)and acesulfame（AK)was employed. The thermal stability and volatility of the sweeteners or their solution(propylene glycol-glycerol mixture as the solvent) were analyzed with thermogravimetry and differential scanning calorimetry analysis, respectively. The coil-burnt experiment was conducted with the coils absorbed the sweetener solution in a Muffle furnace, and the effect of sweeteners on the burnt degree of coil was investigated with visual inspection and whiteness measurement. The assayed sweeteners can be entirely aerosolized by PG-VG in the absence of coil. The ratio of propylene glycol to glycerol, baking temperature, baking time and sweetener type are the influence factors for the coil whiteness after burning. By baking the coil soaked sweetener solution（4% in e-liquids)at 260 ℃ for 30 min, the mass retention rate of coil follows：sucralose＞AK＞GSG＞Neotame＞FA＞blank, while the whiteness of the baked coil, which indicates less enhancement on the degree of burning followed：GSG-FA＞blank＞ Neotame＞sucralose＞AK. [ABSTRACT FROM AUTHOR]

In this study, a series dual-chamber self-excited oscillation nozzle (SDSON) for atomization was developed for photodecomposition of oily wastewater. In order to address the computational complexity associated with optimizing this nozzle, a surrogate model that integrates computational fluid dynamics simulation is proposed. By employing a multi-objective optimization algorithm that combines Genetic Algorithm and Non-dominated Sorting Genetic Algorithm II, significant improvements in atomization performance have been achieved. The influencing factors of atomization and their interactions on the nozzle's atomization performance have been analyzed. The entropy weight method was employed in conjunction with gray theory to rank the optimal solutions based on weighted correlation evaluation, resulting in the determination of the most favorable design solutions. The optimized design exhibited significant enhancements in turbulence kinetic energy and gas volume fraction at the nozzle outlet. Atomization experiments confirmed that the optimized SDSON generated smaller and more uniformly sized droplets under identical inlet pressure conditions, thereby greatly improving atomization performance. [ABSTRACT FROM AUTHOR]

Ultrasonic atomization is a critical process for producing micrometer-diameter droplets, widely utilized in aerosol drug delivery, spectrometry, and printing. The geometry of the vessel containing the fluid being atomized and the oscillations of its sidewalls play a crucial role in controlling the wave patterns and hence the droplet ejection process, especially at actuation frequencies exceeding 1 MHz. However, the mechanisms behind droplet ejection under high-frequency ultrasonic actuation remain poorly understood. We employ oscillating high-aspect-ratio Silicon microchannels to create ideal conditions where capillary forces, microchannel geometry, and oscillatory motion work together to precisely confine a liquid film and generate droplets with controlled diameters. We show that the three-dimensional vibrations of the microchannels, particularly the interplay between actuation frequency, amplitude, and channel geometry, can be used to effectively tune the ligament development and droplet breakup. This understanding allows us to establish conditions to reduce actuation power and hence minimize heating, control shear stresses and tune the droplet size on-demand without compromising uniformity and throughput. [ABSTRACT FROM AUTHOR]

This study delves into the dynamics of non-simultaneous droplet impacts on solid substrates, focusing on interactions between identical impacting droplets. Comparisons between non-simultaneous and simultaneous impacts are presented to understand the phenomena comprehensively. An in-house-built microcontroller-based droplet generator releases two equal-sized droplets on demand, allowing for simultaneous or non-simultaneous impacts. The interaction between impacting droplets generates an uprising sheet, whose characteristics vary with time lag between impacts, impact Weber number, and inter-droplet spacing. The evolution of central sheet characteristics, lamellae spreading dynamics, splashing mechanism, and secondary atomization is evaluated. Findings reveal that central sheet morphology varies with the time lag between impacts, transitioning from a two-dimensional (2D) "semilunar" sheet (vertical or inclined) with a linear base to a three-dimensional (3D) sheet with a curved base, increasing the probability of secondary atomization. The temporal evolution of the central sheet position, height, and inclination angle is governed by the momentum of spreading lamellae. A novel scaling law for maximum sheet extension and a theoretical expression for surface liquid spread are proposed, consistent with the measurements. The characteristics of secondary droplets generated during non-simultaneous impacts are similar to those from simultaneous impacts, with the size of the secondary droplets being one order of magnitude larger than those expected from isolated single-droplet impacts. [ABSTRACT FROM AUTHOR]

Impinging-jet injectors, liquid–liquid coaxial swirl injectors, and liquid–liquid pintle injectors are representative liquid–liquid injectors in liquid rocket engines (LRE). For these liquid–liquid injectors, the atomization processes all involve the liquid impingement, including jet–jet, sheet–sheet, and jets/sheet–sheet impingement, respectively. After impingement, a liquid sheet forms and fragments. Based on these similarities, reviewing published literature on the spray characteristics of these three liquid–liquid injectors in LRE is necessary and will facilitate the investigation of spray characteristics of liquid–liquid pintle injectors to meet the progress of variable-thrust LRE. This review covers the following aspects of these injectors: basic spray morphology, liquid sheet characteristics and disintegration mechanisms, and atomization characteristics. For impinging-jet injectors, rim instability and impact wave play crucial roles in spray morphology and disintegration. Jet Weber number is of great importance for liquid sheet breakup length and mean droplet diameter. In the case of liquid–liquid coaxial swirl injectors, the overall spray morphology is similar to that of pressure swirl injectors, but it may feature two separate liquid sheets. The recess length strongly influences spray morphology, spray angle, breakup length, and Sauter mean diameter. Liquid–liquid pintle injectors can be simplified to injection element, in which the spray morphology resembles a cloak-like shape. In a complete pintle injector, the spray forms a conical liquid sheet. Momentum ratio proves to be the most significant parameter for predicting spray angle. Although the review indicates substantial progress has been made in understanding spray characteristics of liquid–liquid injectors, there remain several shortcomings that require further research, particularly for pintle injectors, which can be learned from the other two injectors. [ABSTRACT FROM AUTHOR]

The pandemic and all of its restrictions dominated public attention and social practices for almost three years. There was declared a state of exception in many national contexts during the pandemic. A revolution took place in the governing of bodies and the obstruction of sociality or the basic togetherness of humans. In a direct, physical way, the pandemic regulations were radically individualizing to a degree that had not been seen in either normal societies or normal crises and emergencies. This pandemic condition of being exposed represented a kind of extreme object existence. [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]

Acidification is an important factor in the aging of paper literature. Since most of the paper is sized and the surface tension of water is high, it is usually difficult for aqueous phase deacidification agent to penetrate the paper resulting in uneven deacidification. The addition of surfactant can effectively reduce the liquid surface tension and enhance the effect of deacidification with wetting properties improvement. In this paper, polysorbate-80 and polyether-modified trisiloxane surfactants were added to sodium propionate aqueous deacidification agent separately, researching the effect of wettability on the paper literature deacidification by ultrasonic atomization. The results show that SP-TRSE is effective, the maximum enhancement of deacidification agent absorption after adding wetting additives is 238.20 %, the minimum standard deviation of water content and alkali reserve after treatment is 3.87 and 0.005 respectively, the maximum increase in the internal mass fraction of sodium is 0.29 %. [ABSTRACT FROM AUTHOR]

Dental enamel is a mineralized extracellular matrix, and enamel defect is a common oral disease. However, the self‐repair capacity of enamel is limited due to the absence of cellular components and organic matter. Efficacy of biomimetic enamel mineralization using calcium phosphate ion clusters (CPICs), is an effective method to compensate for the limited self‐healing ability of fully developed enamel. Preparing and stabilizing CPICs presents a significant challenge, as the addition of certain stabilizers can diminish the mechanical properties or biosafety of mineralized enamel. To efficiently and safely repair enamel damage, this study quickly prepared CPICs without stabilizers using the atomization method. The formed CPICs were evenly distributed on the enamel surface, prompting directional growth and transformation of hydroxyapatite (HA) crystals. The study revealed that the mended enamel displayed comparable morphology, chemical composition, hardness, and mechanical properties to those of the original enamel. The approach of repairing dental enamel by utilizing ultrasonic nebulization of CPICs is highly efficient and safe, therefore indicating great promise. [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]

In port fuel injection (PFI) gasoline engines, combustion fluctuations are caused by the interaction of various factors during ignition. Variations in the fuel deposition on the intake port walls cause fluctuations in the fuel supply to the combustion chamber and in the fuel concentration distribution, which causes knocking. In addition, when a large amount of fuel deposition occurs, it flows into the cylinder in liquid form without vaporizing, generating unburned hydrocarbons. In the previous report, we confirmed that the fuel adhesion amount on the port wall can be reduced by increasing the fuel injection pressure. In this paper, we investigated fuel atomization under even higher injection pressure conditions than the injection pressure range commonly used in intake port injection, with the aim of further reducing the amount of adhesion. In this paper, shadowgraph photography and Super High Spatial Resolution Photography were used to visualize and measure the free-spray jet morphology and atomization characteristics. The effect of high injection pressure to like direct injection, which on the Jet configuration and atomization characteristics of the spray. The results showed that the droplet diameter changed significantly from 1 to 3 MPa (Wavy region) to 4 MPa (Spray region), but no significant change was observed after 8 MPa (Spray region, Spray region with secondary breakup), and that the droplet diameter did not decrease after 8 MPa. [ABSTRACT FROM AUTHOR]

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An efficient implementation for approximate inclusion of the three-body operator arising in transcorrelated methods via exclusion of explicit three-body components (xTC) is presented and tested against results in the "HEAT" benchmark set [Tajti et al., J. Chem. Phys. 121, 011599 (2004)]. Using relatively modest basis sets and computationally simple methods, total, atomization, and formation energies within near-chemical accuracy from HEAT results were obtained. The xTC ansatz reduces the nominal scaling of the three-body part of transcorrelation by two orders of magnitude to O ( N 5 ) and can readily be used with almost any quantum chemical correlation method. [ABSTRACT FROM AUTHOR]

A new approach for generating Gaussian basis sets is reported and tested for atoms from H to Ne. The basis sets thus calculated, named SIGMA basis sets, range from DZ to QZ sizes and have the same composition per shell as Dunning basis sets but with different treatment of the contractions. The standard SIGMA basis sets and their augmented versions have proven to be very suitable for providing good results in atomic and molecular calculations. The performance of the new basis sets is analyzed in terms of total, correlation, and atomization energies, equilibrium distances, and vibrational frequencies in several molecules, and the results are compared at several computational levels with those obtained with the corresponding Dunning and other basis sets. [ABSTRACT FROM AUTHOR]

We investigate the optimization of flexible tailored real-space Jastrow factors for use in the transcorrelated (TC) method in combination with highly accurate quantum chemistry methods, such as initiator full configuration interaction quantum Monte Carlo (FCIQMC). Jastrow factors obtained by minimizing the variance of the TC reference energy are found to yield better, more consistent results than those obtained by minimizing the variational energy. We compute all-electron atomization energies for the challenging first-row molecules C2, CN, N2, and O2 and find that the TC method yields chemically accurate results using only the cc-pVTZ basis set, roughly matching the accuracy of non-TC calculations with the much larger cc-pV5Z basis set. We also investigate an approximation in which pure three-body excitations are neglected from the TC-FCIQMC dynamics, saving storage and computational costs, and show that it affects relative energies negligibly. Our results demonstrate that the combination of tailored real-space Jastrow factors with the multi-configurational TC-FCIQMC method provides a route to obtaining chemical accuracy using modest basis sets, obviating the need for basis-set extrapolation and composite techniques. [ABSTRACT FROM AUTHOR]

Ab initio investigation of the spectroscopic constants, bond dissociation energies of germanium monohalides, germanium dihalides and their ionic systems, viz. GeX, GeX−, GeX+, GeX2, GeX2− and GeX2+ (X = F, Cl, Br and I) have been carried out using correlation consistent triple-zeta basis sets for F and Cl and similar triple-zeta basis sets with RECPs for Ge, Br and I atoms. Geometry and frequency of all the neutral and ionic systems of germanium halides are obtained using MP2, CCSD(T) and QCISD(T) methods. The energetics are obtained at the CCSD(T)//MP2, QCISD(T)//MP2, CCSD(T) and QCISD(T) levels. Electron affinity (EA) and ionization potential (IP) of the monohalides and dihalides are reported to be consistent with the data available in literature. The bond dissociation energies (BDEs) to various dissociation asymptotes for most of the ionic systems are to be reported new in literature. The BDEs of the neutral germanium dihalides GeX2 are calculated by using the BDEs of GeX2− and GeX2+ ions and EA and IP of the associated neutral systems. A good agreement is found between the calculated values and the data wherever available. The BDEs of GeX2 for higher halogen member are reported to be new in literature. The enthalpies of formation for atomization and ionization of the neutral GeX2 dihalides are also reported here. The enthalpies of ionization are reported first time in literature and found consistent with other group IV dihalides. The reported molecular properties may be helpful to understand the chemistry involved in the plasma-assisted fabrication process of the Ge-based modern microelectronic devices, as well as will serve as a future reference. [ABSTRACT FROM AUTHOR]

BACKGROUND: The unmanned aerial spraying systems (UASS) have gained widespread use for plant protection in recent years. However, spray drift from UASS is a major concern when controlling weeds over large areas and warrants a thorough investigation. This study examined the atomization characteristics of the herbicide florpyrauxifen‐benzyl under downwash airflow using a UASS spray test platform. Potential spray drift was assessed using a test bench (TB) and airborne drift collectors (ADCs) in the field under low wind speeds (<1 m s−1). RESULTS: Atomization characteristics were significantly affected by the spray liquid, adjuvant, nozzle type and spray pressure. The addition of an adjuvant reduced the liquid sheet length, improved physicochemical properties and increased droplet size under the downwash airflow field. Drift evaluation in the field using the TB revealed that sediment spray drift predominantly occurred from the middle to the entire length of the device when fine‐to‐medium droplets were produced after the sprayer passed. ADC assessment found that higher flight altitudes and finer droplets resulted in higher drift values, whereas the addition of an adjuvant and the use of an air‐induction nozzle reduced drift <3 m aboveground. CONCLUSION: The combination of using TB in the target area and ADCs in the off‐target area as an alternative method to determine residual droplets in the current airflow provided valuable insights into airborne drift assessment for UASS. © 2024 Society of Chemical Industry. [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]