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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]

Air-delivered spraying can enhance the effective transport and uniform coverage of fog droplets into the interior of the tree crown. However, it is still unclear on the effect of the intensity of air-delivered flow on the response of a single leaf to the motion state and the microcosmic settlement of fog drop. In this study, a single leaf of a pear tree was placed under the stable air flow in the test section of the wind tunnel equipment. The wind vibration response test was carried out on the leaves of a single pear tree. Four feature points were then marked on the leaves, in order to represent the leaf morphology. Binocular high-speed cameras were used to track the feature points on the leaves. The three-dimensional spatial motion model of simulated leaves was constructed to decompose into several sub-stages for subsequent analysis. A systematic analysis was made on the spatial motion trajectory of feature points, in order to explore the effect of droplet deposition on the leaf surface. The research results were as follows. The leaves showed static stability, swing, and a large number of twisting and turning complex motions under the action of wind-driven air flow. The critical response speed of wind vibration was defined as the generation of a large number of twisting motions. Once the wind speed was lower than the critical airflow speed of wind vibration, the leaves were basically lifted at the angle position in a static and stable state. When the air velocity was greater than or equal to the critical, the dynamic stable state of the leaves was destroyed into a compound motion response state of large spatial swing, turnover, and torsion, indicating the periodic motion state of the leaves under the action of strong air. Specifically, the total travel distances of leaf tips in a space movement period were 180.61, 1140.77, and 766.33 mm, respectively, at the speed of 5, 7, and 9 m/s, and the torsion angles were 290.7°, 896.8°, and 716.2°, respectively. In the test of leaf droplet deposition, the spray droplets were deposited mainly on the side of the leaf facing the airflow direction, when the airflow velocity was lower than 5 m/s. There was also an increase in the airflow velocity. The coverage rate of droplet deposition on the front of the leaf gradually decreased from 43.2% to 10.3%. When the airflow velocity was greater than the critical wind response velocity of 5 m/s, the fog droplets were deposited on both sides of the leaves. However, the droplets were deposited mainly on the opposite side of the leaves with better hydrophilicity. The spatial pose and motion of leaves were also simulated, according to the actual coordinates in the instantaneous position of leaves under the space motion. The finding can further reveal the interaction and deposition between the air flow carrying fog droplets and the leaves in the air-driven sprayer. [ABSTRACT FROM AUTHOR]

This study examines the impact of canopy density, side wind speed, nozzle tilt angle, and droplet size on droplet penetration during plant protection spraying operations. Experiments conducted in citrus orchards evaluated how side wind speed and nozzle tilt angle influence droplet penetration across various canopy densities. A Phase Doppler Analyzer (PDA) was used to assess droplet size variations under different nozzle tilt angles and side wind speeds, yielding a multiple linear regression equation (R2 = 0.866) that links nozzle tilt angle and side wind speed with droplet size. Results showed that droplet size decreases with increasing nozzle tilt angle at a constant crosswind speed. Further experiments investigated the effects of droplet size and canopy leaf area density on droplet penetration, involving three canopy leaf area densities, four wind speeds, and six nozzle tilt angles. Droplet deposition and canopy coverage were measured under various spraying parameters, with conventional operations (0° nozzle tilt and orthogonal wind speeds) serving as controls. The study found that adjusting nozzle tilt angle and wind speed enhances droplet penetration in different canopy structures. Optimal parameters varied with leaf area density (LAD): an 18° tilt angle and 3 m/s wind speed for a LAD of 5.94 m3/m3, a 45° tilt angle and 2 m/s wind speed for a LAD of 8.47m2/m3, and a 36° tilt angle and 3 m/s wind speed for a LAD of 11.12m2/m3. At 1 m/s, droplet deposition followed a downward parabolic trend with changes in nozzle tilt angle, whereas at 2 m/s, deposition followed an upward parabolic trend. At a side wind speed of 3 m/s, droplet deposition remained unchanged with nozzle tilt angle but decreased with increasing canopy density. Nonlinear regression analysis indicated that leaf area density had a greater impact on deposition differences than droplet size, with droplet penetration decreasing as leaf area density increased. This study provides a reference for enhancing fog droplet penetration techniques in plant protection operations, offering practical guidelines for optimizing spraying conditions and improving pesticide use efficiency in different canopy structures. [ABSTRACT FROM AUTHOR]

In order to observe the metal transfer behavior in CO2 gas-shielded arc welding, an optical imaging system was established and video images of droplet were captured by a high-speed camera. Based on these images, the droplet size at the moment of short-circuit was accurately measured by ellipsoid-sphere conversion method, and the effects of welding parameters including welding current, welding voltage, wire extension and welding speed on droplet size were also analyzed. The results show that, the droplet size is inversely proportional to welding current and proportional to welding voltage. With the increase in the length of wire extension, the droplet size decreases first and increases later, within the allowable welding range, welding speed hardly affects the droplet size. Lastly, considering both welding efficiency and welding quality, the optimal welding parameters are determined. [ABSTRACT FROM AUTHOR]

Water mist charging and solution active treatment, as two kinds of efficient dust removal methods, showed good dust removal effect when they used independently. In order to explore the settling effect of the combined use of the two on fine dust, sodium dodecyl sulfate (SDS) surfactant was used to prepare the active solution, and copper burr ring electrode was used for corona charging. Under the background of micron droplet field charging, the charging effect of micron active droplet and its wettability to anthracite were investigated. The results show that the active solution is more sensitive to electric field than pure water. Water mist charging and solution activity treatment showed synergistic effects on enhancing droplet fragmentation, reducing droplet size and enhancing solution wettability. Compared with ordinary water mist, micron-charged active water mist has higher capture efficiency for anthracite dust, and sedimentation efficiency for total dust and respirable dust is up to 91.77% and 90.45%.

The effects of water mist concentration and droplet size on the inhibition of gas-liquid two-phase detonation are studied. The characteristics of the structure of the detonation wave, the interaction between the detonation wave and water mist, and the mechanism of water mist inhibition are analyzed. The interaction between iso-octane gas-liquid detonation wave and water mist results in the inhibition of the chemical reaction, and the decrease of combustion rate is the basic reason for the inhibition of water mist. Under the action of detonation waves, water mist flows and evaporates at high velocity, and the heat absorbed by evaporation reduces the chemical reaction rate of fuel to achieve effective inhibition of the detonation. The flame front and pressure wave front of the detonation wave are basically synchronous; after the detonation wave is effectively inhibited by water mist, the length between the pressure wave front and flame front increases gradually. The detonation inhibition effect improves with increasing water mist concentration in the range of 120–350 g/m3 in the model. The inhibition of detonation increases slightly as the size of water mist decreases in the range of 50 μm-200 μm. The optimal concentration range and droplet size range of water mist to inhibit explosion are obtained. The achievements provide an important reference for the design of explosion inhibition by water mist in hazardous explosion areas and have potential applications. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the airborne exposure to aerosols according to the particle size distribution of three different spray types (nano-nozzled spray gun, low-temperature steam spray, and fogger) and compare the concentrations of inhaled aerosols between children and adults. Airborne aerosols released from three products were observed using size-segregated particle measurements, and particle concentrations deposited in the respiratory tracts of adults and children were estimated using multi-path particle dosimetry lung deposition models. All types of sprayers generated the most nanoparticles (~100 nm). Due to their higher respiratory rate than adults, a larger number of particles <1.0 μm deposited in the children's respiratory tracts was higher. The sequences of the total number of particles in the respiratory regions after spraying nano-nozzled spray gun and fogger were alveolar (AL)>tracheobronchial (TB)>head airway (HA) in adults and AL>HA>TB in children. Meanwhile, the trend of low-temperature steam spray was AL>TB>HA in adults and AL>TB>HA in children. [ABSTRACT FROM AUTHOR]

Abstract To effectively control the dust generated by coal mining operations, a new type of cyclonic pneumatic mist curtain dust control device was developed. Using CFD software, numerical simulations were conducted on the internal airflow velocity field, the exit velocity of the cyclonic pneumatic mist curtain, and the mist droplet particle field of the curtain. Experiments were carried out to measure the spray coverage, droplet size, and the dust control performance of the model device. The results indicate that when the water pump supply pressure is 8 MPa, the fan supply wind speed is 12 m/s, and the nozzle installation angle is 75 degrees, the cyclonic pneumatic mist curtain dust control device model operates under optimal conditions. The effective coverage of the cyclonic mist curtain is 380 × 3300 mm, fully suppressing dust generation on one side of the curtain. An optimal dust removal distance of about 90 cm was determined. After installing the cyclonic pneumatic mist curtain dust control device, the average dust reduction efficiency for respirable dust reached 91.07%, and the overall dust reduction efficiency achieved 93.34%.

This article reports the design and experiment of a novel air-assisted nozzle for pesticide application in orchard. A novel air-assisted nozzle was designed based on the transverse jet atomization pattern. This article conducted the performance and deposition experiments and established the mathematical model of volume median diameter (D50) and liquid flow rate with the nozzle design parameters. The D50 of this air-assisted nozzle ranged from 52.45 mmto 113.67 mm, and the liquid flow rate ranged from 142.6 ml/min to 1,607.8 ml/min within the designed conditions. These performances meet the low-volume and ultra-low-volume pesticide application in orchard. The droplet deposition experiment results demonstrated that the droplet coverage distribution in different layers and columns is relatively uniform, and the predicted value of spray penetration (SP) numbers SPiA, SPiB, and SPiC (i =1,2,and3)are approximately 70%, 60%, and 70%, respectively. The droplet deposits on the foliage of the canopy (inside and outside) uniformly bring benefit for plant protection and pesticide saving. Compared with the traditional air-assisted nozzle that adopts a coaxial flow atomization pattern, the atomization efficiency of this air-assisted nozzle is higher. Moreover, the nozzle air pressure and liquid flow rate are considerably lower and greater than the traditional air-assisted nozzle, and these results proved that this air-assisted nozzle has great potential in orchard pesticide application. The relationship between the D50 and nozzle liquid pressure of this air-assisted nozzle differs from that of traditional air-assisted nozzles due to the atomization pattern and process. While this article provides an explanation for this relationship, further study about the atomization process and mechanism is needed so as to improve the performance. [ABSTRACT FROM AUTHOR]

Ti-6Al-4V is a titanium alloy with a high strength-to-weight ratio and is corrosion-resistant, but its limited thermal conductivity makes processing difficult and reduces tool life. Machining with mist lubrication, or minimum quantity lubrication (MQL), is an ecological and sustainable machining method. However, it is unclear how, droplet size inherent to MQL is affected by cutting fluids and operational conditions. On the other hand, conventional lubrication is not environmentally friendly. The effectiveness of MQL as a cooling agent during the end milling processes is investigated using three coolant types of distinguishable qualities and various air pressures. Droplet size is determined experimentally using Phase Doppler Anemometry. The experimental data gathered about the SMD of particles, is used to validate the finite volume CFD model of MQL spray process, built with ANSYS Fluent. The air pressure and coolant flow rate effects on the Sauter Mean Diameter are studied for three different coolants by CFD simulation. Out of three coolants, 120 V cutting oil with a density of 820 kg/m3 and specific heat of 4.30 kJ/kgK, when mixed with 150ml/hr flow rate at 3 bar air pressure produced the lowest machining temperature of 147.90 °C and tool wear of 0.0508 mm corresponding to SMD of 35.50 μm. [ABSTRACT FROM AUTHOR]

To effectively control the dust generated by coal mining operations, a new type of cyclonic pneumatic mist curtain dust control device was developed. Using CFD software, numerical simulations were conducted on the internal airflow velocity field, the exit velocity of the cyclonic pneumatic mist curtain, and the mist droplet particle field of the curtain. Experiments were carried out to measure the spray coverage, droplet size, and the dust control performance of the model device. The results indicate that when the water pump supply pressure is 8 MPa, the fan supply wind speed is 12 m/s, and the nozzle installation angle is 75 degrees, the cyclonic pneumatic mist curtain dust control device model operates under optimal conditions. The effective coverage of the cyclonic mist curtain is 380 × 3300 mm, fully suppressing dust generation on one side of the curtain. An optimal dust removal distance of about 90 cm was determined. After installing the cyclonic pneumatic mist curtain dust control device, the average dust reduction efficiency for respirable dust reached 91.07%, and the overall dust reduction efficiency achieved 93.34%. [ABSTRACT FROM AUTHOR]

The effects of biodiesel addition on gasoline fuel dribbling process and characteristics after the end-of-injection (EOI) were investigated in a constant volume chamber at different injection pressures and ambient temperatures. The fuel dribbling process was recorded with high spatial and time resolution by using the microscopic shadow imaging technique, and the corresponding dribble velocity, dribble volume and droplet size were extracted. The results showed that the fuel dribbling experienced four typical morphological structures (spray-like, membrane-type, ligament-type, droplets) after the EOI under all the tested conditions. Additionally, increased biodiesel proportion in the blends caused decreased dribble velocity, longer dribbling duration, and increased droplet size, indicating deteriorated breakup and atomization processes of the dribbling flow. Moreover, the higher injection pressure increased the dribble amount but reduced the dribbling duration and droplet size. The increased ambient temperature caused faster evaporation of the dribbling fuel, resulting in a significant decrease in the dribble size. So, these two strategies were believed to be overall favorable to restrain the adverse effect on gasoline fuel dribbling characteristics caused by the addition of biodiesel. [ABSTRACT FROM AUTHOR]

Droplet size is a crucial success factor for increased particle size in the agglomeration process. Thus, this work aimed to analyze the physicochemical properties of maltodextrin solutions used as the binder, their influence on the size of the formed droplets, and their relationship to particle growth. The primary CMC particles had an average size of 295.5 ± 10.0 µm, and at the end of the process, the agglomerates reached chord lengths ranging from 336.5 ± 10.6 µm to 378.3 ± 8.6 µm. Three maltodextrin solutions (5.0%, 20.0%, and 35.0% w/w) were characterized for that in terms of physicochemical properties and droplet size, and following that, the binder concentrations, binder flow rate, and atomizing air pressure were evaluated. The binder liquid concentration is the most outstanding parameter for the agglomeration process regarding particle growth under experimental conditions. [ABSTRACT FROM AUTHOR]

As known from recent COVID-19 pandemics, droplets emitted by humans during various respiratory activities can contain pathogens and be responsible for infectious disease transmission. The study of droplet dispersion is fundamental to estimate and possibly control the associated risk. Numerical simulations are useful as they make it possible to afford the complexity of this phenomenon. However, they require precise droplet and air properties as input data in order to provide reliable results. A lack of knowledge still exists due to the difficulties in measuring droplet sizes over a wide range and in capturing sizes and velocities simultaneously. In this work, numerical simulations were conducted using experimental data collected by the authors, taking advantage of innovative information about particle velocity relative to their size. Two measurement campaigns involving 20 volunteers were carried out. The size and the three velocity components of the ejected droplets were simultaneously measured for droplets down to 2 μ m using an extended version of the Interferometric Laser Imaging Droplet Sizing technique. The effect of droplet initial velocity on droplet dispersion is assessed, along with the effect of other parameters, namely, ambient temperature and air ejection velocity. Both inert and evaporating droplets are considered in the simulations. [ABSTRACT FROM AUTHOR]

Abstract Lipid oxidation in emulsions is hypothesised to increase with decreasing droplet size, as this increases the specific oil–water interfacial area, where lipid oxidation is expected to be initiated. In literature, however, contradictory results have been reported, which can be caused by confounding factors such as the oil droplet polydispersity and the distribution of components between the available phases. In this work, monodisperse surfactant-stabilised emulsions with highly controlled droplet sizes of 4.7, 9.1, and 26 µm were produced by microfluidic emulsification. We show that lipid oxidation increases with decreasing droplet size, which we ascribe to the increased contact area between lipids and continuous phase prooxidants. Besides, a significant amount of oxygen was consumed by oxidation of the surfactant itself (Tween 20), an effect that also increased with decreasing droplet size. These insights substantiate the importance of controlling droplet size for improving the oxidative stability of emulsions.

Lipid oxidation in emulsions is hypothesised to increase with decreasing droplet size, as this increases the specific oil–water interfacial area, where lipid oxidation is expected to be initiated. In literature, however, contradictory results have been reported, which can be caused by confounding factors such as the oil droplet polydispersity and the distribution of components between the available phases. In this work, monodisperse surfactant-stabilised emulsions with highly controlled droplet sizes of 4.7, 9.1, and 26 µm were produced by microfluidic emulsification. We show that lipid oxidation increases with decreasing droplet size, which we ascribe to the increased contact area between lipids and continuous phase prooxidants. Besides, a significant amount of oxygen was consumed by oxidation of the surfactant itself (Tween 20), an effect that also increased with decreasing droplet size. These insights substantiate the importance of controlling droplet size for improving the oxidative stability of emulsions. [ABSTRACT FROM AUTHOR]

The study focuses on the flow patterns and pressure drop characteristics of three crude oils and water in a horizontal pipe. The experimental results showed that the transformation boundary of the flow pattern and phase inversion water fraction were related to the flow parameters. Comparing the three oils, it was found that the viscosity and composition of the oil also significantly influence the flow performance, which can be explained by the adsorption properties of the asphaltenes at the oil-water interface. In particular, the droplet size in water-in-oil dispersion flow was observed and measured. It showed that the water droplet size decreased with the increase of oil viscosity, the decrease of water content, the drop of temperature, and the growth of mixing velocity, probably due to higher shear stress and lower frequency of collision and coalescence between droplets. The apparent viscosity of water-in-oil emulsions was calculated by the rheological model, and the qualitative relation between flow parameters and interfacial area concentration on apparent viscosity was obtained. Taking the influence of interfacial area concentration into consideration, a simple and accurate viscosity model was established based on dimensional analysis, which is of great significance for process design in gathering and transportation systems. [ABSTRACT FROM AUTHOR]

Weed control success with pre-emergence (PRE) herbicides is affected by environmental factors including rainfall and plant residue. Two greenhouse experiments were conducted to evaluate PRE herbicide efficacy against johnsongrass [Sorghum halepense (L.) Pers.], prickly sida (Sida spinosa L.) and velvetleaf (Abutilon theophrasti Medik.). One experiment investigated herbicide efficacy under two crop residue amounts (2500 and 5000 kg ha−1) and the second examined herbicide efficacy influenced by simulated rain at two, four, and eight days after application (DAA). Five herbicides (pendimethalin, metribuzin, clomazone, imazethapyr and pyroxasulfone) and four nozzles types (XR, ULD, TTI and TTI60) were used. Nozzle type did not affect weed control across residue levels. Pendimethalin better controlled S. halepense under the low residue level. Imazethapyr efficacy for S. spinosa and A. theophrasti increased under high residue level. Imazethapyr applications for S. spinosa and A. theophrasti control were more effective when sprayed with the TTI nozzle regardless of rainfall timing. Longer periods without rain after application improved pendimethalin efficacy against S. spinosa and A. theophrasti, while pyroxasulfone better controlled S. spinosa with rain two DAA. Metribuzin and clomazone provided the best weed control among herbicides for all residue levels and rainfall scenarios. [ABSTRACT FROM AUTHOR]

The physical stability of a whey protein (WP)-stabilized red palm oil (RPO) emulsion as affected by the type and concentration of WP used was evaluated by monitoring the changes in its droplet characteristics after storage and accelerated testing. Emulsions containing 30% (v/v) RPO were stabilized by WP isolate 90 (WPI), WP concentrate 80 (WPC80), or WP concentrate 76 (WPC76) at various concentrations (2.5–15% (w/v)) via emulsification employing a two-step rotor-stator homogenization combined with a phase inversion technique. Based on the results, changes in droplet characteristics did not always represent the visually observed stability of the emulsions. In this study, WPCs performed better than WPI in forming a stable RPO emulsion. Higher WP concentrations produced smaller emulsion droplet sizes with better emulsion stability when stored at varied temperatures (i.e., 30 °C, 45 °C, and 60 °C). However, when stored at 60 °C, all the emulsions produced were least stable. Based on the results, the 15% WPC76-stabilized emulsion showed the best stability. This study found that the droplet size characterization could not fully explain the stability of the emulsion, and the emulsion investigated destabilized through different dominant mechanisms when it was stored compared to when it was centrifuged. This study provides information needed for developing a stable WP-stabilized emulsion to be the RPO carrier system. [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.)

This study was designed to illustrate the effects and the mechanism of ultrasound-assisted emulsification (UAE) treatment and carboxymethyl cellulose (CMC) addition on the rheological behavior and microstructure of myofibrillar protein (MP)-soybean oil-based emulsion gels. Our results indicated that both CMC addition and UAE treatment enhanced the apparent viscosity, Hook and Voigt elastic modulus, storage modulus, and loss modulus of MP-based emulsion gels, especially for the combined CMC and UAE treatment. The size of emulsion gel droplets was decreased and the concentrations of protein and CMC in the emulsion gels were improved after UAE treatment. A protein-coated oil-filled gel network structure was formed for the non-UAE treated MP-based emulsion gel whilst a protein-coated oil-participated network structure was formed for the UAE treated sample. UAE treatment significantly increased the random coil content, surface hydrophobicity, and zeta potential while decreasing the free and total sulfhydryl groups of MP. In summary, UAE treatment and CMC addition could modify the gel network, change the electrostatic and hydrophobic interactions, and enhance the disulfide bonds to improve the rheological properties of MP-soybean oil-based emulsion gel. [ABSTRACT FROM AUTHOR]

The interfacial area between two phases plays a crucial role in the mass transfer rate of gas–liquid processes such as absorption. In this context, the droplet size distribution within the flow field of a droplet-based absorber significantly affects the surface area, thereby influencing the absorption efficiency. This study focuses on developing a computational fluid dynamics (CFD) model to predict the size and distribution of water droplets free-falling in a transparent square tube. This model serves as a digital twin of our experimental setup, enabling a comparative analysis of experimental and computational results. For the accurate measurement of droplet size and distribution, specialized experimental equipment was developed, and a high-speed camera along with Fiji software was used for the capturing and processing of droplet images. At the point of injection and at two different heights, the sizes and distributions of falling droplets were measured using this setup. The interaction between the liquid water droplets and the gas phase within the square tube was modeled using the Eulerian–Lagrangian (E-L) framework in the STAR-CCM+ software. The E-L multiphase CFD model yielded approximations with errors ranging from 11 to 27% for various average mean diameters, including d 10 , d 20 , d 30 , and d 32 , of the liquid droplets at two distinct heights (200 mm and 400 mm) for both nozzle plates. This comprehensive approach provides valuable insights into the dynamics of droplet-based absorption processes. [ABSTRACT FROM AUTHOR]

Introduction: Agriculture is the largest user of water globally (i.e., 70% of freshwater use) and within the United States (i.e., 42% of freshwater use); irrigation ensures crops receive adequate water, thereby increasing crop yields. Surfactants have been used in various agricultural spray products to increase spray stability and alter droplet sizes. Methods: The effects of the addition of surfactant (0.1 wt% Surfactin; surface tension of 29.2 mN/m) to distilled water (72.79 mN/m) on spray dynamics and droplet formation were investigated in four flat fan (206.8-413.7 kPa), one full cone (137.9-413.7 kPa), and three LEPA bubbler (41.4-103.4 kPa) nozzles via imaging. Results and discussion: The flat fan and cone nozzles experienced second windinduced breakup (i.e., unstable wavelengths drive breakup) of the liquid sheets exiting the nozzle; the addition of surfactant resulted in an increased breakup length and a decreased droplet size. The fan nozzles volumetric median droplet diameter decreased with the addition of surfactant (e.g., decreased by 26.3-65.6 µm in one nozzle). The full cone nozzle volumetric median droplet diameter decreased initially with the addition of surfactant (27.8, 14.3, and 13.4 µm at 137.9, 206.8, and 310.3 kPa respectively), but increased at 413.7 kPa (24.3 µm). Sprays from the bubbler nozzles were measured and observed to experience Rayleigh (i.e., the droplets form via capillary pinching at the end of the jet) and first wind-induced breakup (i.e., air impacts breakup along with capillary pinching). The effect of Surfactin on droplet size was minimal for the 41.4 kPa bubbler nozzle. The addition of surfactant increased the diameter of the jet or ligament formed from the bubbler plate, thereby increasing the breakup length and the droplet size at 68.9 and 103.4 kPa (droplet size increased by 750.6 and 4,462.7 µm, respectively). [ABSTRACT FROM AUTHOR]

This work demonstrated the criterion of shear stability of emulsion explosive matrices (EEM), combined with rheology test, interfacial tension test, droplet size test and the crystallization test of emulsion explosive matrices. The shear stability of emulsion explosive matrices was defined as the characteristic refinement time of the droplet size decrease in emulsification process. The constitutive relationship between the characteristic refinement time and droplet size of inner phase droplets was proposed by theoretical analysis and experiments on the emulsification process of emulsion explosive matrices. By analyzing the relationship between rheological properties and characteristic refinement time of emulsion explosive matrices, the relationship model between Bingham coefficient and dimensionless coefficient was established to characterize the shear stability of emulsion explosive matrices. The effects of shear strength, shear time and shear shape on the stability of emulsion explosive matrices were studied. In addition, there exists a critical value to quantitatively characterize the shear stability of emulsion explosive matrices. [ABSTRACT FROM AUTHOR]

Emulsions have garnered significant attention within a variety of industries, including pharmaceuticals, food production, and cosmetics. The importance of emulsions across these sectors is attributed to their versatility and unique properties, such as increased interfacial area and the ability to deliver compounds insoluble in water or to mask the flavor of unpalatable ingredients. A comprehensive and precise assessment of the physicochemical properties, structural features, and stability of emulsions is an indispensable phase in the pursuit of new formulations and the improvement of manufacturing protocols. The characterization of emulsions encompasses an array of methodologies designed to determine their attributes, such as droplet size, distribution, concentration, surface charge, and others. In this review, we explore the techniques most frequently used to characterize emulsions and critically assess the significance each method holds in understanding the behavior and predicting the stability of emulsions. We elucidate the basic principles of these methods while emphasizing what information can be gathered from them, and how to effectively interpret this information to optimize the properties of emulsions, crucial from the standpoints of food and other industries, such as long-term stability and easy processing. [ABSTRACT FROM AUTHOR]

Abstract Nucleic acid amplification testing (NAAT) remains one of the most reliable methods for pathogen identification. However, conventional bulk NAATs may not be sufficiently fast or sensitive enough for the detection of clinically‐relevant pathogens in point‐of‐care testing. Here, we have developed a digital droplet RT‐LAMP (ddRT‐LAMP) assay that rapidly and quantitatively detects the SARS‐CoV‐2 viral E gene in microfluidic drops. Droplet partitioning using ddRT‐LAMP significantly accelerates detection times across a wide range of template concentrations compared to bulk RT‐LAMP assays. We discover that a reduction in droplet diameter decreases assay times up to a certain size, upon which surface adsorption of the RT‐LAMP polymerase reduces reaction efficiency. Optimization of drop size and polymerase concentration enables rapid, sensitive, and quantitative detection of the SARS‐CoV‐2 E gene in only 8 min. These results highlight the potential of ddRT‐LAMP assays as an excellent platform for quantitative point‐of‐care testing.

Since Complete Fluidic Sprinklers (CFS) cannot function well in low-pressure environments, Dynamic Fluidic Sprinkler (DFS) were developed to address this issue. In 2021, research in the field and laboratory were conducted to examine how well DFS and CFS performed hydraulically in both indoor and outdoor conditions. In this investigation, a Thiess Clima laser precipitation monitor was used to evaluate the droplet size and velocity distribution of two different types of sprinklers indoors. From the findings, DFS velocities ranged from 0.1 to 4 m/s whereas CFS ranged from 0.1 to 5.3 m/s. The maximum frequency value was obtained at velocities of 1 m/s for each combination. The DFS had a slightly greater discharge coefficient and spray pattern than the CFS. The DFS's maximum spray range was 12.2 m, while the CFS's maximum spray range was 10.8 m, with standard deviations of 1.07 and 1.66, respectively. Under high wind speed conditions, the maximum combined Coefficient of Uniformity (CU) of DFS and CFS were 81.1% and 78%, respectively. For a given pressure and sprinkler spacing, DFS delivered higher CU values than CFS, especially while running at low pressure, demonstrating that DFS offered a more favoured water distribution pattern at low pressure. At different distances from the sprinkler, the highest application rates for DFS and CFS were 6.7 mm h−1 at 7 m and 6.5 mm h−1 at 7 m, respectively. A comparison of DFS and CFS under hydraulic performance indicated that DFS had a better performance than CFS. The study can serve as a guide for how to conserve water in sprinkler-irrigated fields.

Abstract Droplet size has significant scientific and industrial relevance in the effectiveness of atomization for several applications in the chemical, pharmaceutical, and food industries. This technology is widely employed in the food industry for processes such as spray drying, microencapsulation, edible coatings, and food disinfection, among others. This work comprehensively reviews the effect of liquid properties and equipment operating factors influencing droplet size in pneumatic and ultrasonic atomization. The discussion on the atomization theories includes the different models for estimating droplet size as a function of selected variables for both processes. The different model approaches are reviewed, focusing on their advantages, disadvantages, applications, and limitations. Furthermore, selected models were employed to carry out different sensitivity analyses showing the effect of variables related to the liquid properties, the type and characteristics of the atomizers, and the operating conditions, allowing the reader to appreciate the most critical factors in both atomization systems.

Movement of liquid iron micrometeoroid in the Earth atmosphere is simulated to find the time-dependence of its acceleration, velocity and coordinates as well as the length of luminous trajectory when the micrometeoroid is still melted. In the simulations it is assumed that the maximum size of the stable droplet is determined by aerodynamic fragmentation of the moving droplet occurring when the Weber number exceeds its critical value. Two different initial altitudes h of droplet formation were analysed: 80 km and 50 km, both for a wide range of initial velocities between 6 and 20 km/s. Depending on their initial velocity, exceeding the Earth’s escape velocity equal 11.2 km/s, the maximum radius of solid spherules, emerging from solidified final droplet, is predicted here to lie between (a) 55 and 100 μm for h = 80 km, and (b) 10 and 30 μm for h = 50 km.

Copyright of Progress in Plant Protection is the property of Institute of Plant Protection 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.)

Copyright of Misr Journal of Agricultural Engineering is the property of Egyptian National Agricultural Library (ENAL) 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.)

AbstractThe objectives undertaken in current work were to develop a new solid self-microemulsifying drug delivery system (S-SMEDDS) for poorly water-soluble Rosuvastatin Calcium (RST) and evaluate its antihyperlipidemic activity in rodent model. Solubility assessment in variety of excipients, screening studies and optimization of pseudoternary plots helped in development of liquid SMEDDS. Liquid SMEDDS of RST contained Capryol 90, Kolliphor EL and Transcutol HP as oil phase, surfactant and co-surfactant respectively which were evaluated for release, self-emulsification ability, percentage transmittance and globule size. Florite RE was used as the adsorbent to transform the optimized liquid SMEDDS into non-coherent powder which was then examined for micromeritic properties, solid state characterization and in vitro dissolution studies. It was additionally investigated for antihyperlipidemic activity in rats subjected to high fat diet. Optimized liquid SMEDDS of RST was found to undergo a swift transformation in a microemulsion having globule size in nanometric size range with consistent size distribution. The liquid SMEDDS adsorbed on Florite RE exhibited favorable micromeritic properties and spherical shape. XRD studies indicated amorphization of RST due to its molecular dispersion in S-SMEDDS. Enhanced in vitro rate of dissolution of optimized formulation was observed in comparison to pure drug and commercial product. There was considerable reduction (p < 0.001) in serum levels of total cholesterol (TC), triglycerides (TG), low-density lipoproteins (LDL-C), very low-density lipoproteins (VLDL-C) when S-SMEDDS was administered and increment in high-density lipoproteins (HDL-C) level compared to plain drug suspension. RST S-SMEDDS holds great potential for enhancement of its physiochemical along with biological attributes. [ABSTRACT FROM AUTHOR]

In this research, the Volumetric Median Diameters (VMDs), Relative Span (RS), percentage of droplets with a diameter smaller than 100 µm (V100), and percentage of drift (% drift) of four droplet classes (Fine, Medium, Coarse, and Very Coarse) were analyzedin two spray volumes (77 L.ha-1and 144 L.ha-1) employinga tank-mix of atrazine and nicosulfuron herbicides (2500 + 15 gaiha-1), usingParticle/Droplet Imaging Analyze (PDIA) and wind tunnel techniques. The experiments were performed under Completely Randomized Design, in a 4 × 2 factorial scheme (droplet classes × sprayvolumes). Data underwent analysis of variance and Tukey's test at 5%, and the correlation between variables was computedconsidering Pearson's coefficient at 1% and 5%. The VMD of all droplet classes was considerably distinct in the two spray volumes. In both application spray volumes, the minimum VMD for the Coarsedropletclass classification was not attained. The highest means of RS were detectedin the spray volume of 77 L.ha-1. All treatments demonstratedsignificant differences in the analysis of V100 and % drift, with the highest means observed in the Fine droplet (144 L.ha-1) and Medium (77 L.ha-1). A negative correlation existed between VMD × V100 and VMD × % drift and a positive correlation between V100 × % drift in the two spray volumes. RS was negatively correlated with VMD and positively with V100 and % drift, in the spray volume of 77 L.ha-1. In the spray volume of 144 L.ha-1, the correlation between RSand VMD, V100, and % drift was insignificant. [ABSTRACT FROM AUTHOR]

To understand the exact transmission routes of SARS-CoV-2 and to explore effects of time, space and indoor environment on the dynamics of droplets and aerosols, rigorous testing and observation must be conducted. In the current work, the spatial and temporal dispersions of aerosol droplets from a simulated cough were comprehensively examined over a long duration (70 min). An artificial cough generator was constructed to generate reliably repeatable respiratory ejecta. The measurements were performed at different locations in front (along the axial direction and off-axis) and behind the source in a sealed experimental enclosure. Aerosols of 0.3–10 µm (around 20% of the maximum nuclei count) were shown to persist for a very long time in a still environment, and this has a substantial implication for airborne disease transmission. The experiments demonstrated that a ventilation system could reduce the total aerosol volume and the droplet lifetime significantly. To explain the experimental observations in more detail and to understand the droplet in-air behaviour at various ambient temperatures and relative humidity, numerical simulations were performed using the Eulerian–Lagrangian approach. The simulations show that many of the small droplets remain suspended in the air over time instead of falling to the ground. [ABSTRACT FROM AUTHOR]

A study of the aerodynamic characteristics of aerosol expiration is important for understanding the size distribution of droplet concentration in COVID-19 disease transmission. This study measured the initial concentration and size distribution of droplets released during four breathing processes: nose breathing, mouth breathing, reading alphabets and counting numbers. Influencing factors on droplet generation were studied by statistical analyses. Significant differences in droplet concentration among the four breathing activities in pairs were found (p < 0.001), except for reading alphabets and numbers (p = 1). The droplet concentration during nose breathing (p < 0.05), but not mouth breathing (p = 0.136), of male subjects, was found significantly higher than that of female subjects. The droplet concentration generated by speaking during letters reading with special phonemes, for example, /i:/, was significantly (p < 0.05) higher than reading letters without phonemes. The discharged droplet sizes from four breathing activities were dominated by small droplets (d p < 1.037 μm of over 50% and d p < 2.642 μm of over 80%). Basically, no particles larger than 8 μm were detected by the aerodynamic particle sizer. The inference indicates a possible aerosol transmission of disease during non-symptomatic aerosol-producing activities such as breathing or speaking and may elucidate the disease transmission pathway of COVID-19. [ABSTRACT FROM AUTHOR]

Clove essential oil is traditionally used as an anesthetic, analgesic, or insecticide, and recently, its applications as an antimicrobial, antioxidant, or anticancer agent have been explored. Nanoemulsions are thermodynamically unstable dispersions (d < 100 nm) produced by mixing two immiscible phases, which, in many cases, improve the stability and biological activities of functional ingredients for pharmaceutical, cosmetic, or food applications. This research optimized the formation of clove essential oil nanoemulsions by employing response surface methodology. The surfactant concentration was minimized by modifying the percentage of clove oil (0–100%), surfactant content (1–4%), and oil phase content (0–20%). In the optimum conditions, a nanoemulsion (93.19 ± 3.92 nm) was produced using 1.0% surfactant and 2.5% oil phase of which 50.7% was clove essential oil. The optimized nanoemulsion was stable in rapid stability tests (centrifugation, freezing–thawing, and heating–cooling), but its average droplet size increased during storage at different temperatures. The nanoemulsion contains a phenolic content equivalent to 736 mg gallic acid/mL. However, the antioxidant capacity of the essential oil (IC50 = 0.78 µg/mL) was dismissed in the nanoemulsion (IC50 = 2.43 µg/mL). The antimicrobial activity of the nanoemulsion showed strain–dependent behavior with MIC ranging from 0.0468 to 0.75 mg/mL, where E. coli and S. typhimurium were the most susceptible pathogenic bacteria. Finally, nanoencapsulation of clove oil showed higher in vitro cytotoxic activity against Caco–2 cancer cells (227 μg/mL) than free clove essential oil (283 μg/mL), but nanoemulsion (306 μg/mL) was less effective than oil (231 μg/mL) in the HT–29 line. This research shows the potential of clove essential oil nanoemulsions for developing biological therapies to treat diseases. [ABSTRACT FROM AUTHOR]

Droplet size and interfacial tension are key parameters related to two‐phase flow. However, current methods for measuring these parameters are usually based on visualization and are therefore not applicable for invisible two‐phase flow systems. Moreover, real‐time determination of interfacial tension is difficult because conventional methods cannot be employed in the flow field. This study presents a novel method for simultaneously measuring the droplet size and real‐time interfacial tension in a two‐phase flow system. A T‐shaped microdevice was designed and integrated with the two‐phase flow equipment. The pressure variation as the droplets flowed through the microdevice was used as a probe to detect the two key parameters, that is, visualization is not required. Monodispersed and multidispersed droplet flows in different equipment were used to verify the method. Both the droplet size distribution and real‐time interfacial tension can be determined using the developed approach. [ABSTRACT FROM AUTHOR]

The paucity of suitable drug formulations for pediatric patients generates a need for customized, compounded medications. This research study was set out to comprehensively analyze the physical properties of the new, proprietary anhydrous oral vehicle SuspendIt® Anhydrous, which was designed for compounding pediatric oral liquids. A wide range of tests was used, including sedimentation volume, viscosity, droplet size after dispersion in simulated gastric fluid, microscopic examination and content uniformity measurements to evaluate the properties of the anhydrous vehicle. The results showed that the vehicle exhibited consistent physical properties under varying conditions and maintained stability over time. This can be attributed to the unique blend of excipients in its formulation, which not only maintain its viscosity but also confer thixotropic behavior. The unique combination of viscous, thixotropic and self-emulsifying properties allows for rapid redispersibility, sedimentation stability, accurate dosing, potential drug solubility, dispersion and promotion of enhanced gastrointestinal distribution and absorption. Furthermore, the vehicle demonstrated long-term sedimentation stability and content uniformity for a list of 13 anhydrous suspensions. These results suggest that the anhydrous oral vehicle could serve as a versatile base for pediatric formulation, potentially filling an important gap in pediatric drug delivery. Future studies can further investigate its compatibility, stability and performance with other drugs and in different clinical scenarios. [ABSTRACT FROM AUTHOR]

In order to study the effect of surfactant compound on droplet size characteristics in fog field, an experimental platform was independently built in this paper. Anionic surfactant AES, amphoteric surfactant LAB-35 and non-ionic surfactant AEO-9 were selected for binary monomer re-combination, and different ratios of surfactant compound solution were used for experiments. The droplet sizes D10 , D50 , D90 , Dv and Δs were analyzed under different pressures. The results show that when the nozzle diameter is constant, the droplet size of surfactant compound solution decreases with the increase of spray pressure, and the droplet size distribution is more uniform with the increase of spray pressure. In the range of 5∶1-1∶5 ratio of AES and AEO-9 compound solution, the spray droplet particle size is smaller than that of AES and AEO-9 monomer solution. AES and LAB-35, AEO-9 and LAB-35 compounds are all easy to reduce the spray droplet size of LAB-35 monomer solution.

This paper deals with the investigation of the performance of a nozzle used for intra-soil application of liquid mineral fertilizers (LMF), determination of the range of spray angle, fall angle, droplet size, spray distribution characteristics, and substantiation of its dependence on the nozzle design parameters. The proposed nozzle has a jet-impact channel and deflector slot design with very compact overall dimensions. It can be mounted on a deep tillage knife (wing) with a height of 12–14 mm and provides flat fan spray with a high spraying angle. The following range of effective parameters has been determined: the feed channel diameter is 1–1.6 mm, the slot height is 0.35–0.7 mm, and impact surface diameter 5–8 mm. The resultant spray angle is 170–175°, and the fall angle diapason is 5–10°. These parameters contribute to determination of the tillage knife design parameters such as knife height and the height of spray window, as well as the nozzle installation parameters such as t, n and m in future studies. The results can be useful for nozzle industries, particularly in developing the flat fan nozzles with wide spray angle. Overall, the nozzle design is applicable to use for intra-soil application of liquid mineral fertilizes with deep tillage knives.

Including the correct combination of factors for the application technology of pesticides can improve their distribution on their targets. The aim of this work was to use multivariate analysis to study the effect size and the order of influence of three factors that interfere with pesticide application technology in corn crops. A 2 × 2 × 3 factorial experiment was conducted with two droplet size classes (fine and coarse), two application rates (80 and 150 L ha−1), and the presence of adjuvants (mineral oil one and two, and no adjuvant). A knapsack boom sprayer was used for the applications. Droplet deposition on the corn leaves was evaluated by detecting a tracer added to the spray via spectrophotometry and the droplet spectrum by analyzing water-sensitive papers. Univariate and multivariate statistical analyses were performed to integrate the variables analyzed. Droplet size has proven to be the most important factor in spraying planning, and the second factor is the application rate. With the association between fine droplets and higher application rates, a better performance was obtained in coverage, droplet density, and droplet deposition.