Spray Time Research Articles

Development of SiO2/TiO2/Al2O3-based/TiO2 coating for preventing sulfide corrosion in thermal power plant boilers

In thermal power generation equipment, wall thinning on boiler tubes due to sulfide corrosion has been a problem. The methods for resolving or preventing the problem are coating of a nickel-chromium film by plasma spraying, weld cladding, and replacement of water wall tubing. These methods are expensive and time consuming. Therefore, an economical and straightforward coating technique was developed for preventing sulfide corrosion on boiler tubes. The developed coating has a four-layered structure comprising, in order from the boiler tube substrate, thin films of (1) a SiO2 layer, (2) a TiO2 layer, (3) an Al2O3-based layer, and (4) a TiO2 layer. The coating reduced corrosion to 25% or less compared with an uncoated part under a simulated condition (Gas: CO2/H2/N2/CO/H2O = 12%/4%/67%/8%/9% H2S 330 ppm, Temperature: 500 °C). It was found that the coating on boiler tubes is exceptionally durable and continues to be effective for more than 2 years in actual power plants. This coating process can be applied to a large area, and the work period is short. When the coating area is 100 m2, the working time is 3 days and total spraying time is only 7 h.

Effects of Spraying Various Nanoparticles at Early Ages on Improving Surface Characteristics of Concrete Pavements

In this study, the effects of spraying nanoparticles with different geometries (nano-SiO2, nano-halloysite, and nano-montmorillonite) on surface characteristics of concrete pavement in terms of microstructure. The initial and final setting times of mixtures were determined to investigate the proper spraying time for applying on the pavement surface at early ages. To precisely investigate the microstructural properties, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and atomic force microscopy (AFM) were used. The results revealed that spraying nanoparticles improved the abrasion and skid resistance as well as transport properties of the concrete surface, especially at the initial setting time. According to the tribology testing, the surface friction coefficient of sprayed samples compared to the reference sample (not sprayed) was increased 28%, on average. AFM results verified that this growth is due to the improved surface roughness and van der Waals forces. Based on the FTIR results, the abrasion resistance of the samples gradually diminished by increasing the depth due to reduction of nanoparticles penetration, thus, reducing its positive effect. In addition, a good relationship with regression coefficient of 0.79 was found between the surface tensile strength and the abrasion resistance of the specimens.

Optimization of coating processes of mini tablets with polyvinylpyrrolidone solutions in an acoustic levitator

The aim of the current study is to optimize the bed fluidized coating process of mini tablets by means of an acoustic levitator. The optimized coating parameters, which have to be set in a fluidized bed reactor, can be determined by means of contactless levitation of a single mini tablet in an acoustic levitator equipped with an ultrasonic atomizer. Mini tablets were positioned in a contactless way in the levitator and coated with polyvinylpyrrolidone (PVP) solution. The influences of process parameters on the coating, such as temperature, mass fraction, volumetric flow rate and spray time, are analyzed in an acoustic levitator in a cost- and time-saving manner. The results from the acoustic levitator were comparable to those performed in a fluidized bed reactor. A design of experiments was performed to analyze the effects of those parameters on the mass of coating thickness. The surfaces of the samples coated in the acoustic levitator at 40 °C were comparable to samples coated in a fluidized bed reactor at 40 °C by using scanning electron microscopy (SEM).

Evaluating Optimal Spray Timing, Planting Date, and Current Thresholds for Lygus lineolaris (Hemiptera: Miridae) in Virginia and North Carolina Cotton.

Economically damaging infestations of Lygus lineolaris (Palisot de Beauvois) (Hemiptera: Miridae), the tarnished plant bug, have been increasing in North Carolina and Virginia cotton since 2009. We conducted experiments to compare prophylactically timed sprays based on cotton phenology and current action thresholds based on sweep net and drop cloth sampling. In the second year of the study, we included planting date as a factor, with early and late-planted cotton. We found L. lineolaris nymph densities were reduced by at least 60% in North Carolina and 74% in Virginia in threshold plots when compared with the untreated control. Protecting the crop from first square through the fourth week of bloom afforded at least 30% control across planting dates in Virginia and at least 40% control in North Carolina. Economic returns were two to three times greater in early-planted cotton than in late-planted cotton. Treating cotton at action threshold or using prophylactic sprays from first square until the sixth week of bloom in early-planted cotton yielded over $500/ha in net returns in both North Carolina and Virginia. This study supports previous research that shows controlling L. lineolaris infestations during squaring and early weeks of flowering is critical for maximizing yield potential. Our findings also suggest that prebloom and bloom thresholds based on adult and nymphal density devised in the Mid-South may need revision in North Carolina and Virginia.

Effects of Various Aeroponic Atomizers (Droplet Sizes) on Growth, Polyphenol Content, and Antioxidant Activity of Leaf Lettuce (Lactuca sativa L.)

HighlightsThe atomizer droplet size should be considered an important factor when designing aeroponic systems.Airless atomizers had significant positive effects on plant growth, total polyphenol content, and antioxidant activity.Airless atomizers and a spraying interval of 20 min on and 3 h off was the best combination for lettuce plants.Abstract. Throughout our literature review, the effects of various aeroponic atomizers (droplet sizes) on specific leafy plant growth and quality were minimally reported. Lettuce ( L.) is one of the most popular leafy vegetables consumed around the world. The present study sought to determine the effects of various aeroponic atomizers (droplet sizes) on the growth, total polyphenol content, and antioxidant activity of lettuce plants. Aeroponic systems were designed and manufactured using three kinds of atomizers: air-based (A1), airless (A2), and ultrasonic fogger (A3). The South China Agricultural leafy vegetable B nutrient solution was selected as the cultivating solution. Additionally, the spraying time and spraying interval were set at 20 min on and 3 h off. The sizes of the droplets generated by these atomizers were measured using a laser particle size analyzer, and the measured average droplet sizes generated by the A1, A2, and A3 atomizers were 23.281, 46.386, and 3.451 µm, respectively. The results showed that the lettuce plants treated with the A2 atomizers exhibited more significant effects on the growth, total polyphenol content, and antioxidant activity of the lettuce compared to those treated with the A1 and A3 atomizers. The results indicated that nutrient solution droplet size should be considered an essential factor when designing an aeroponic system. Keywords: Aeroponic, Antioxidant activity, Soilless, Spraying time, Total polyphenol content.

Morphological, optical and electrical properties of spray coated zinc ethyl xanthates for decomposition within a poly(3-hexylthiophene-2,5-diyl) matrix

This work investigates the deposition of hybrid layers, for next generation in energy conversion, via spray coating. Understanding the effect that this deposition procedure has on these layers could lead to the rapid development of these technologies, for both laboratory applications and commercialisation. Synthesised zinc ethyl xanthate and poly(3-hexylthiophene-2,5-diyl) was spray-coated on substrates and heated to a temperature of 160 °C, to the hybrid film. Optical, morphological and conductive properties of these films were investigated and linked to the spray coating duration. It was revealed that shorter-duration spray times led to relatively low conductivity and smoother films, moreover, an increase in spraying duration also led to an increase in conductivity, but with increased roughness, from 6.178 nm to 8.317 nm. As the spray time was further increased factors, including film layering effects, led to a gradual decrease in conductivity accompanied by a decrease in the roughness. Smoother films were shown to result in higher light absorption, characterised by wider band gaps, which could be due to the crystal structure of the inorganic phase. The controllability of this rapid, facile, and inexpensive spray deposition process was then demonstrated in fabrication of prototype photovoltaic devices.

Structural, optical and electrical properties of CuBiS<SUB align="right">2 thin films deposited by spray pyrolysis at different deposition times

Reproducible and good quality copper bismuth sulphide (CuBiS2) thin layer were situated on preheated glassy slide substrates made implementing the spraying pyrolysis approach at distinctive times of spraying 15, 30, 45, and 60 min with a fixed substrate temperature 400°C. The effect of spray time on the structural, morphology, optical and electrical benefits of the CuBiS2 thin films produced by spray pyrolysis methodology were studied. The structure was studied by XRD methodology. The surface texture of the produced films was considered by SEM. The optical benefits of the CuBiS2 films were inquired working with the spectrophotometric method in which the optical transmittance and reflectance beyond a wavelength range 200-2500 nm were measured. The d.c. conductivity was studied at different temperatures for all the prepared CuBiS2 thin films.

Composite Paint based on Barium-Strontium-Hexaferrite as an Absorber of Microwaves at X-band Frequency

A composite of barium-strontium-hexaferrite based paint has been investigated as a microwave absorber. The samples were prepared by solid-state reaction method with a mechanical alloying technique using HEM and calcined at 1000 °C for 5 hours. XRD was used for phase and crystal structured-form analysis, and TEM was for surface morphology analysis.VNA was used to analyzethe ability to absorb microwaves. The composite has a hexagonal structure. The surfacemorphology has been homogeneous. The best ability to absorb microwaves was obtained in samples with 10 spraying times, with an RL value ∼ -4.02 dB at f = 9.7 GHz.

INCREASING PRODUCTIVITY BY USING A MIXER TRANSPORT UNIT FOR LOADING SPRAYERS

Spraying of plants against diseases and pests should be carried out within a short time. One way to increase the performance of sprayers is by reducing the unproductive spray time. For this purpose, a transport mixing unit is available on the market, which reduces the preparation time of the working solution. This unit and the benefits of using it are not well known to many farmers. Existing research shows that its use results in a double increase in productivity compared to transporting water from the sprayer itself. This article proposes a methodology for determining the variation in sprayer performance when loaded with a working solution by transport mixing unit compared to loading it with water by an ordinary tank with the same parameters. Analytical dependencies have been generated for determining the duration of individual operations during operation of the sprayer and mixing unit, as well as for calculating the percentage increase in the productivity of the sprayer. The methodology has been demonstrated for specific sprayers and mixers under specific conditions. In this case, it was found that filling the sprayer with a solution instead of pure water could increase its productivity by 34.5%.

Structural, optical and electrical properties of CuBiS<SUB align="right">2 thin films deposited by spray pyrolysis at different deposition times

Reproducible and good quality copper bismuth sulphide (CuBiS2) thin layer were situated on preheated glassy slide substrates made implementing the spraying pyrolysis approach at distinctive times of spraying 15, 30, 45, and 60 min with a fixed substrate temperature 400°C. The effect of spray time on the structural, morphology, optical and electrical benefits of the CuBiS2 thin films produced by spray pyrolysis methodology were studied. The structure was studied by XRD methodology. The surface texture of the produced films was considered by SEM. The optical benefits of the CuBiS2 films were inquired working with the spectrophotometric method in which the optical transmittance and reflectance beyond a wavelength range 200-2500 nm were measured. The d.c. conductivity was studied at different temperatures for all the prepared CuBiS2 thin films.

INCREASING PRODUCTIVITY BY USING A MIXER TRANSPORT UNIT FOR LOADING SPRAYERS

Spraying of plants against diseases and pests should be carried out within a short time. One way to increase the performance of sprayers is by reducing the unproductive spray time. For this purpose, a transport mixing unit is available on the market, which reduces the preparation time of the working solution. This unit and the benefits of using it are not well known to many farmers. Existing research shows that its use results in a double increase in productivity compared to transporting water from the sprayer itself. This article proposes a methodology for determining the variation in sprayer performance when loaded with a working solution by transport mixing unit compared to loading it with water by an ordinary tank with the same parameters. Analytical dependencies have been generated for determining the duration of individual operations during operation of the sprayer and mixing unit, as well as for calculating the percentage increase in the productivity of the sprayer. The methodology has been demonstrated for specific sprayers and mixers under specific conditions. In this case, it was found that filling the sprayer with a solution instead of pure water could increase its productivity by 34.5%.

Multi-objective Bayesian optimization of super hydrophobic coatings on asphalt concrete surfaces

Abstract Conventional snow removal strategies add direct and indirect expenses to the economy through profit lost due to passenger delays costs, pavement durability issues, contaminating the water runoff, and so on. The use of superhydrophobic (super-water-repellent) coating methods is an alternative to conventional snow and ice removal practices for alleviating snow removal operations issues. As an integrated experimental and analytical study, this work focused on optimizing superhydrophobicity and skid resistance of hydrophobic coatings on asphalt concrete surfaces. A layer-by-layer (LBL) method was utilized for spray depositing polytetrafluoroethylene (PTFE) on an asphalt concrete at different spray times and variable dosages of PTFE. Water contact angle and coefficient of friction at the microtexture level were measured to evaluate superhydrophobicity and skid resistance of the coated asphalt concrete. The optimum dosage and spay time that maximized hydrophobicity and skid resistance of flexible pavement while minimizing cost were estimated using a multi-objective Bayesian optimization (BO) method that replaced the more costly experimental procedure of pavement testing with a cheap-to-evaluate surrogate model constructed based on kriging. In this method, the surrogate model is iteratively updated with new experimental data measured at proper input settings. The result of proposed optimization method showed that the super water repellency and coefficient of friction were not uniformly increased for all the specimens by increasing spray time and dosage. In addition, use of the proposed multi-objective BO method resulted in hydrophobicity and skid resistance being maximally augmented by approximately 23% PTFE dosage at a spray time of 5.5 s. Highlights Effects of spray time and dosage on the hydrophobicity and friction of asphalt were investigated. A layer-by-layer method was utilized for spray depositing polytetrafluoroethylene on an asphalt concrete. The optimum dosage and spay time were estimated by using a multi-objective Bayesian optimization method. An acquisition function that can tackle problems involving multiple objective functions was proposed. The optimum hydrophobicity and skid resistance were achieved with 23% PTFE dosage and at a spray time of 5.5 s.

Efficacy of Kaolin and Screen Duo Spraying on Fruit Sunburn, Yield and Fruit Quality of Keitt Mango Fruits

This study was carried out during two successive seasons (2016 and 2017) on six years old Keitt mango trees grafted on Succary seedlings as rootstocks and planted at 2×3 meters in sandy soil under drip irrigation system in Kafr El-Sohbi village, Qalubia Governorate, Egypt., To study the influence of kaolin and screen duo foliar application on fruit sunburn, yield and fruit quality. Hence, the foliar applications treatment were kaolin (aluminum silicate) at 25,50 and 75g/L and screen duo at 6,12 and 18 cm3/L sprayed once at mid of June and also sprayed twice at mid of both June and July during both seasons of study as well as, control (tap water spray). The influence was evaluated through the response of the different measurements as yield, sunburned fruit measurements, fruit quality and fruit skin color parameters with kaolin and screen duo concentrations and times of spray (once or twice). The obtained results revealed that the response to screen duo was more pronounced and differences between its three concentrations were significant in most cases as compared each other from one hand and the highest one (18 cm3/L.) was the most effective in most cases from the other hand. Referring the specific effect of times of spray (once or twice) data display obviously that the highest values in most cases were significantly in concomitant to fruits sprayed twice during both seasons of study. Anyhow, it could be concluded that, spraying screen duo at 12 and/or 18 cm3/L twice in summer months (at mid of both June and July) had a positive effect to prevent fruit sunburn damage and improved yield and fruit quality of Keitt mango fruits.

Evaluation of some Bread Wheat Cultivars Productivity and Quality to Foliar Spray Time by Different ZINC Oxide Nanoparticles Sizes

A field experiment was carried out during 2016/ 2017 and 2017/ 2018 seasons at the Agronomy Department Experimental Farm, Agriculture Faculty, Assiut University to study the effect of foliar spray time by different zinc oxide nanoparticles sizes on productivity and quality of some bread wheat cultivars. The experiment was laid out in randomized complete block design (RCBD) using split plot in strips arrangement with three replications. Zinc dioxide nanoparticles size (control, 20.7, 23.0 and 27.0 nm) were allocated horizontally

Experimental investigation of gliding arc plasma fuel injector for ignition and extinction performance improvement

Flame extinction at high-altitude is one of the serious safety problems for aero-engines. The low pressure and temperature at high-altitude make it difficult to relight after extinction. Plasma-assisted combustion has been widely investigated in aerospace propulsion systems, while the mechanism is still not clear. In this study, a novel gliding arc plasma fuel injector using alternating current discharge is proposed to obtain reliable altitude relight performance and wider lean blow-out limits. The ignition and extinction experiments of gliding arc plasma fuel injector using 5 °C and −30 °C kerosene (RP-3) were conducted. A thin and string-like gliding arc plasma column was observed with repeating phases of breakdown between the fuel atomizer and venturi nozzle, extension with rotating airflow and column quenching. The optical emission spectroscopy of gliding arc plasma in gliding arc plasma fuel injector indicated the significant thermal effect caused by the arc column. Using gliding arc plasma fuel injector, the ignition limit was greatly extended, almost to the lean blow-out limits for the low temperature fuel. Low temperature and low injection pressure lead to much larger droplets and irregular injection cone. Influenced by heating and hydrodynamic effect of gliding arc plasma, the drop size at −30 °C kerosene spray decreases from around 150 μm to 30 μm, which is a main reason for ignition range extension. The equivalence ratios of lean blow-out were extended by up to 48% and 47% using 5 °C and −30 °C kerosene, respectively. Several light hydrocarbons, such as CH4 (1.26 SLM), C2H4 (1.31 SLM) and C2H2 (2.30 SLM) with larger laminar flame propagation velocity, were detected as reforming products. Both heating and reforming effects contribute to the lean blow-out limit extension. The residence time of kerosene sprays in gliding arc plasma fuel injector is the determining factor for conversion capability.

Validation of a Florida Strawberry Anthracnose Fruit Rot (AFR) Warning System in Iowa.

Field validation of a disease-warning system for strawberry anthracnose fruit rot (AFR), caused by Colletotrichum acutatum sensu lato, that was originally developed for use in Florida was conducted in Iowa from 2012 to 2014. Day-neutral strawberry (cv. Tristar) was artificially inoculated with the pathogen at the start of the fruit maturation period. A factorial combination in replicated trials of two spray timing methods (the Florida warning system and prescheduled, calendar-based timing) and two fungicides (captan and pyraclostrobin) was compared, along with a nonsprayed control. The calendar-based and warning system-based treatments provided statistically equivalent control of AFR incidence compared with the nonsprayed control, and the warning system treatments required an average of 1.7 fewer fungicide sprays annually than the calendar-based treatments. Further analysis of the field data suggested that the warning system might underestimate AFR risk under high disease pressure; in these circumstances, a lower action threshold value may need to be adopted. Overall, these results indicated that the Florida warning system can be valuable for helping Midwest strawberry growers control AFR with less reliance on fungicide sprays, but it may require modification to account for periods of high inoculum pressure, subject to results of further field trials.

PENGARUH FAKTOR KARAKTERISTIK PETANI DAN METODE PENYEMPROTAN TERHADAP KADAR KOLINESTERASE

The farmers' efforts to reduce pests are using pesticides. But, there is an adverse effect farmer’s health, namely pesticide poisoning. Based on Litbang (2004), the incidence of poisoning were about 80% in the developing countries. The purpose of this study is to analyze factors which are affected with cholinesterase levels of rice farmers who sprayed pesticides in Sumberejo, Kecamatan Balong Kabupaten Ponorogo. This study used an observational study design with cross sectional analytic. The sample was all rice farmers who sprayed pesticides in rice plants between 1-7 days before they blood was taken for examination of the enzyme cholinesterase. Total respondents are 40 farmers. The study was in Sumberejo, Kecamatan Balong Kabupaten Ponorogo in July 2013-February 2014. Variables in this study were age, education level, knowledge level, smoking status, used of PPE, work period, the last spraying, direction, time, and duration of spraying, and cholinesterase levels. The primary data was obtained by observation, interview, and spectrophotometer. The technique of data analysis is linier regression test. The results showed that the value of cholinesterase levels is between 5602 U/L-15668 U/L were categorized into moderate and normal. There are no affect characteristic factors (age and work period) on cholinesterase levels. Has affect method of spray (last of spraying) on cholinesterase levels.The conclusion was there is effect between the last of spraying on cholinesterase levels.Keywords: farmers, pesticides, cholinesterase levels

Cooling cows with sprinklers: Effects of soaker flow rate and timing on behavioral and physiological responses to heat load and production

Spray strategies (e.g., flow rate and spray timing) may affect the surrounding microclimate and how cows use soakers, affecting cooling efficiency. Our objective was to evaluate the combined effects of spray timing (i.e., frequency, low: 3 min on, 6 min off; or high: 1.5 min on, 3 min off) and flow rates (3.3 or 4.9 L/min) on behavioral and physiological responses to heat load and production in Holstein cows managed in a freestall barn. In a 2 × 2 Latin square design, 3 cohorts of 4 pairs of cows averaging (±standard deviation) 36.7 ± 5.4 kg/d of milk were tested for 3 d/treatment. Water was sprayed at the feedline from 0815 to 2330 h when air temperature and relative humidity averaged 27 ± 3°C and 37 ± 7%, respectively. The overall quantity of water sprayed was not affected by spray timing; it varied only as a function of flow rate. Cows' posture and location within the pen were measured continuously, whereas feeding and body temperature were recorded every 3 min over 24 h/d. Respiration rates were recorded daily every 45 min from 0900 to 2000 h. Neither spray timing nor flow rates affected posture, location in the pen, feeding activity, or respiration rates. Overall, on average, cows spent 12.6 ± 0.4 h/d lying down and 5.8 ± 0.3 h/d in the feed bunk area. While in the feed bunk area, cows spent 78 ± 3% of their time feeding. Average respiration rate ranged from 57 to 59 ± 3 breaths/min across treatments. Although body temperature tended to be reduced when using higher flow rate, this difference was 0.1°C when comparing 24-h averages (4.9 vs. 3.3 L/min: 38.6 vs. 38.7 ± 0.1°C). Body temperature differences, however, were more marked and statistically different when soakers were cycling, especially between 1100 and 2200 h. Despite this, the magnitude of the hourly differences were <0.2°C. Milk production also tended to increase by 1.5 kg/d when using higher flow rates. When using the same water volume, spray timing did not affect cow behavior, physiology, or production. Flow rate had a small effect on milk production and body temperature but the biological relevance of these differences is unclear, especially in this situation where all cows were relatively cool.

TiO2 Nanocrystal Based Coatings for the Protection of Architectural Stone: The Effect of Solvents in the Spray-Coating Application for a Self-Cleaning Surfaces

A colloidal route was exploited to synthesize TiO2 anisotropic nanocrystal rods in shape (TiO2 NRs) with a surface chemistry suited for their dispersibility and processability in apolar organic solvents. TiO2 NRs were dispersed in chloroform and n-heptane, respectively, and the two resulting formulations were investigated to identify the optimal conditions to achieve high-quality TiO2 NR-based coatings by the spray-coating application. In particular, the two types of TiO2 NR dispersions were first sprayed on silicon chips as a model substrate in order to preliminarily investigate the effect of the solvent and of the spraying time on the morphology and uniformity of the resulting coatings. The results of the SEM and AFM characterizations of the obtained coatings indicated n-heptane as the most suited solvent for TiO2 NR dispersion. Therefore, an n-heptane dispersion of TiO2 NRs was sprayed on a highly porous limestone—Lecce stone—very commonly used as building material in historic constructions and monuments present in Apulia Region (Italy). A comprehensive physical-chemical investigation of the TiO2 NR based treatment on the surface of the stone specimens, including measurements of colour variation, static contact angle, water transfer properties, and morphological characterization were performed. Finally, the photocatalytic properties of the coatings were assessed under solar irradiation by using Lecce stone specimens and Methyl Red as a model target compound. The obtained results demonstrated that TiO2 NRs based coatings can be successfully applied by spray-coating resulting in an effective photocatalytic and hydrophobic treatment, which holds great promise as a material for the environmental protection of architectural stone in the field of cultural heritage conservation.

Experimental study of ultrasonic atomizer effects on values of EC and pH of nutrient solution.

The objectives of this research were to reveal how main working parameters of ultrasonic atomizers would influence key properties of the atomized nutrient solution in an aeroponics system. The Yamazaki tomato nutrient solution was selected as a nutrient example. Uniform design (UD) method U12 (122×13) was adopted to arrange the test. In this test, spraying time and interval time were taken as quantitative factors with 12 levels (10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, and 120 min, respectively), and ultrasonic atomizer frequency was taken as qualitative factor with 3 conditions (28 kHz, 107 kHz, 1.7 MHz). Based on test data, two regression formulations used to predict the values of ΔEC, and ΔpH of atomized Yamazaki tomato nutrient solution was established and inspected. The spraying interval time of ultrasonic atomizers had no significant effect on EC and pH of the atomized Yamazaki tomato nutrient solution; the ultrasonic atomizer frequency was more effective than spraying time on the values of EC and pH; the values of EC and pH became maximum at (f3, T1) = (1.7 MHz, 120 min) and minimum at (f1, T1) = (28 kHz, 10 min). It was concluded that the effect of high-frequency (1.7 MHz) ultrasonic atomizer on EC and pH of the Yamazaki tomato nutrient solution was beyond the standard value for tomato growth. Therefore, the high-frequency (1.7 MHz) ultrasonic atomizer is not suitable for aeroponics cultivation when using the Yamazaki tomato nutrient solution as aeroponics nutrient solution. Keywords: aeroponics, tomato nutrient solution, EC, pH, ultrasonic atomizer frequency, spray time, interval time, uniform design DOI: 10.25165/j.ijabe.20181105.3790 Citation: Lakhiar I A, Liu X D, Wang G Q, Gao J M. Experiment study of ultrasonic atomizer effects on values of EC and pH of nutrient solution. Int J Agric & Biol Eng, 2018; 11(5): 59–64.