Spray Solution Research Articles

Antipathogenic Activity of Betainized Polyethyleneimine Sprays Without Toxicity

Background/Objectives: The design of alternative antipathogenic sprays has recently attracted much attention due to the limitations of existing formulations, such as toxicity and low and narrow efficacy. Polyethyleneimine (PEI) is a great antimicrobial polymer against a wide range of pathogens, but toxicity limits its use. Here, betainized PEI (B-PEI) was synthesized to decrease the toxicity of PEI and protonated with citric acid (CA), boric acid (BA), and HCl to improve antimicrobial activity. Methods: Cytotoxicity of the PEI-based solutions was determined on L929 fibroblast cells. Antibacterial/fungal activity of PEI-based antipathogenic sprays was investigated by microtiter and disc diffusion assays, in addition to bacterial viability and adhesion % of common bacteria and fungi on the PEI-treated masks. Furthermore, the antiviral effect of the PEI-based solutions was determined against SARS-CoV-2 virus. Results: The biosafe concentration of PEI was determined as 1 μg/mL with 75 ± 11% cell viability, but B-PEI and its protonated forms had great biocompatibility even at 1000 μg/mL with more than 85% viability. The antibacterial/fungal effect of non-toxic B-PEI was improved by protonation with BA and HCl with 2.5–10 mg/mL minimum bactericidal/fungicidal concentrations (MBCs/MFCs). Bacterial/fungal viability and adhesion on the mask was almost eliminated by using 50 μL with 5–10 mg/mL of B-PEI-BA. Both protonated bare and betainized PEI show potent antiviral activity against SARS-CoV-2 virus. Conclusions: The toxicity of PEI was overcome by using betainized forms of PEI (B-PEI). Furthermore, the antimicrobial and antiviral efficacy of PEI and B-PEI was improved by protonation with CA, BA, and HCl of amine groups on B-PEI. B-PEI-BA spray solution has great potential as an antipathogenic spray with broad-spectrum antimicrobial potency against harmful bacteria, fungi, and viruses without any toxicity.

Modifying the Refuse Chute Design to Prevent Infection Spread: Engineering Analysis and Optimization

Considering the presence of airborne viruses, there is a need for renovation in refuse chutes, regarded as the first step in recycling household waste in buildings. This study aimed to revise the design of existing refuse chutes in light of the challenging experiences in waste management and public health during the coronavirus pandemic. This research primarily focused on the risks posed by various types of coronaviruses, such as the novel coronavirus (COVID-19) and acute respiratory syndrome (SARS and SARS-CoV), on stainless steel surfaces, with evidence of their survival under certain conditions. Refuse chutes are manufactured from stainless steel to resist the corrosive effects of waste. In examining the existing studies, it was observed that Casanova et al. and Chowdhury et al. found that the survival time of coronaviruses on stainless steel surfaces decreases as the temperature increases. Based on these studies, mechanical revisions have been made to the sanitation system of the refuse chute, thus increasing the washing water temperature. Additionally, through mechanical improvements, an automatic solution spray entry is provided before the intake doors are opened. Furthermore, to understand airflow and clarify flow parameters related to airborne infection transmission on residential floors in buildings equipped with refuse chutes, a computational fluid dynamics (CFD) analysis was conducted using a sample three-story refuse chute system. Based on the simulation results, a fan motor was integrated into the system to prevent pathogens from affecting users on other floors through airflow. Thus, airborne pathogens were periodically expelled into the atmosphere via a fan shortly before the intake doors were opened, supported by a PLC unit. Additionally, the intake doors were electronically interlocked, ensuring that all other intake doors remained locked while any single door was in use, thereby ensuring user safety. In a sample refuse chute, numerical calculations were performed to evaluate parameters such as the static suitability of the chute body thickness, static compliance of the chute support dimensions, chute diameter, chute thickness, fan airflow rate, ventilation duct diameter, minimum rock wool thickness for human contact safety, and the required number of spare containers. Additionally, a MATLAB code was developed to facilitate these numerical calculations, with values optimized using the Fmincon function. This allowed for the easy calculation of outputs for the new refuse chute systems and enabled the conversion of existing systems, evaluating compatibility with the new design for cost-effective upgrades. This refuse chute design aims to serve as a resource for readers in case of infection risks and contribute to the literature. The new refuse chute design supports the global circular economy (CE) model by enabling waste disinfection under pandemic conditions and ensuring cleaner source separation and collection for recycling. Due to its adaptability to different pandemic conditions including pathogens beyond coronavirus and potential new virus strains, the designed system is intended to contribute to the global health framework. In addition to the health measures described, this study calls for future research on how evolving global health conditions might impact refuse chute design.

Experimental Study on the Protective Effect of High Alcoholysis Polyvinyl Alcohol (PVA) Solution Spraying on Loess Fill Slopes

Loess has high water sensitivity and exhibits poor characteristics such as weak cementation and high porosity. Under heavy rainfall, loess fill slopes are prone to erosion and landslides, posing serious threats to public safety and property. In light of these serious threats, this study employed the method of spraying polyvinyl alcohol (PVA) solution to improve loess fill slopes and systematically examine its protective effects. Through field investigations and combined laboratory and outdoor tests, this study comprehensively evaluated the mechanical properties, anti-aging and anti-erosion performance of loess after PVA solution spraying. Scanning electron microscopy was used to reveal the mechanism of PVA action at the microscopic level. The results showed that after treatment with PVA solutions of varying concentrations, the mechanical properties of loess samples were significantly enhanced, while also exhibiting excellent anti-aging and water resistance performance. Additionally, PVA-treated loess fill slopes exhibited excellent rain erosion resistance. A microscopic structural analysis showed that PVA fills the internal pores of loess, strengthens inter-particle bonding, and uses its hydrophobic groups’ water-repellent action to effectively enhance slope stability and erosion resistance. In conclusion, PVA treatment not only significantly enhances the protective effects of loess fill slopes but also holds important value in improving soil sustainability and environmental protection.

Application of Ethephon Manually or via Drone Enforces Bud Dormancy and Enhances Flowering Response to Chilling in Litchi (Litchi chinensis Sonn.)

Ethephon (2-chloroethylphosphonic acid) is frequently used for flush management in order to maximize flowering in litchi. However, the optimal dosage of ethephon, which balances between flush control effect and the detrimental effect on leaves, is unknown. This study aimed to identify the optimal ethephon dosage and test more efficient ethephon application methods, using a drone for flush control and flowering promotion in litchi. The effects of a single manual full-tree spray of 250, 500 or 1000 mg/L of ethephon in early November on the bud break rate, leaf drop rate, net photosynthetic rate, LcFT1 expression and floral induction (panicle emergence rate and panicle number) in ‘Jingganghongnuo’ litchi were examined in the season of 2021–2022. In the season of 2022–2023, the effects of drone application of 1000 mg/L of ethephon in early November on bud growth and floral induction were observed. The results showed that the manual ethephon treatments were effective at enforcing bud dormancy and elongating the dormancy period and that the effects were positively dependent on dosage. One manual spray of 1000 mg/L of ethephon in late autumn enabled a dormancy period of 6 weeks. The treatments advanced seasonal abscission of old leaves in winter and caused short-term suppression on photosynthesis within 2 weeks after treatment. Ethephon treatments, especially at 1000 mg/L, enhanced the expression of LcFT1 in the mature leaves and promoted floral induction reflected by earlier panicle emergence and increased panicle emergence rate and number in the terminal shoot. The floral promotion effect was also positively dosage dependent. The cumulative chilling hours below 15 °C from the date of treatment to the occurrence of a 20% panicle emergence rate were lowered in ethephon treatments. A drone spray of 1000 mg/L of ethephon solution consumed a sixth of the manual spray solution volume and was two thirds less effective in suppressing bud break compared with manual spraying. However, it achieved a significant flowering promotion effect comparable to traditional manual spraying. The results suggest that ethephon application enhanced flowering responsiveness to chilling as well as enforced bud dormancy. The application of ethephon with a drone proved to be an efficient method for flush control and flower promotion.

Simulation of Quench Rate by Jominy End Quench Test for 6082 Aluminium Alloys

In the present study, it is aimed to investigate the influence of quench rate on the hardness and electrical conductivity that obtained after artificial aging by using Jominy End Quench test method. The Jominy End Quench test bars were solution heat treated at 560°C for 3 hours. After solution heat treatment, water, spray, and air quenching medias were used in order to obtain different quench rates. After the quench, quench rate determination, hardness and electrical conductivity measurements were performed for three different quenching medias. Then, artificial aging heat treatment were applied to all samples at 180°C for 8 hours to understand the effect of quench rate on aging process. The relationship between quench rate, hardness and electrical conductivity have presented.

Effects of Spray Adjuvants on Droplet Deposition Characteristics in Litchi Trees under UAV Spraying Operations

In the last decade, unmanned aerial vehicles (UAVs) for plant protection have rapidly developed worldwide as a new method for pesticide application, especially in China and other Asian countries. To improve the deposition quality in UAV applications, adding appropriate types of spray adjuvants into pesticide solutions is one of the most effective ways to facilitate droplet deposition and control efficacy. At present, research on spray adjuvants for UAVs are mainly based on droplet drift and laboratory tests. Few studies have been conducted on the physicochemical properties of spray adjuvants and the effects of droplet deposition characteristics. To explore the properties of four different kinds of spray adjuvants (Mai Fei, Bei Datong, G-2801, and Agrospred 910) and the deposition characteristics of spray adjuvants on litchi leaves, an automatic surface tension meter, a contact angle measuring device, an ultraviolet visible spectrophotometer, and a DJI AGRAS T30 plant protection UAV was used to measure the surface tension, contact angle, and droplet deposition characteristics on litchi under UAV spraying operations. The results showed that the addition of spray adjuvants could significantly reduce the surface tension of the solution. The surface tension value of the solution after adding the spray additives was reduced by 53.1–68.9% compared with the control solution. Among them, the Agrospred 910 spray adjuvant had the best effect on reducing the surface tension of the solution. The contact angle of the control solution on the litchi leaves varied from 80.15° to 72.76°. With the increase in time, the contact angle of the spray adjuvant solution gradually decreased, the Agrospred 910 spray adjuvant had the best effect, and the contact angle decreased from 40.44° to 20.23° after the droplets fell on the litchi leaves for 60 s. The adjuvant solutions increased the droplet size, but the uniformity of the droplet size decreased. The Dv0.5 of different spray solutions ranged from 97.3 to 117.8 μm, which belonged to the fine or very fine droplets, and the Dv0.5 of adjuvants solutions were significantly greater than that of the control solution. The RSs of adjuvant solutions were very similar and ranged from 0.92 to 0.96, all of which were significantly greater than the result of the control solution (0.57). Compared with the deposition of the control solution, the Mai Fei, Bei Datong, and G-2801 solutions clearly increased spray deposition, with total depositions of 0.776, 0.705, and 0.721 μL/cm2, which are all greater than the total deposition of the control solution of 0.645 μL/cm2. The addition of tank-mixed adjuvants could effectively increase the uniformity of the spray deposition, and all the average CVs of adjuvant solutions were lower than 96.86%. On the whole, Mai Fei performed best in increasing the spray deposition and promoting penetration, followed by Bei Datong and G-2801. Meanwhile, the test can also provide a reference for improving the utilization rate of UAV pesticide applications.

Foliar Exposure of Deuterium Stable Isotope-Labeled Nanoplastics to Lettuce: Quantitative Determination of Foliar Uptake, Transport, and Trophic Transfer in a Terrestrial Food Chain.

Nanoplastics (NPs) are widely detected in the atmosphere and are likely to be deposited on plant leaves. However, our understanding of their foliar uptake, translocation, and trophic transfer profiles is limited due to a lack of quantitative analytical tools to effectively probe mechanisms of action. Here, using synthesized deuterium (2H) stable isotope-labeled polystyrene nanoplastics (2H-PSNPs), the foliar accumulation and translocation of NPs in lettuce and the dynamics of NP transfer along a lettuce-snail terrestrial food chain were investigated. Raman imaging and scanning electron microscopy demonstrated that foliar-applied NPs aggregated on the leaf surface, entered the mesophyll tissue via the stomatal pathway, and eventually translocated to root tissues. Quantitative analysis showed that increasing levels of foliar exposure to 2H-PSNPs (0.1, 1, and 5 mg/L in spray solutions, equivalent to receiving 0.15, 1.5, and 7.5 μg/d of NPs per plant) enhanced NP accumulation in leaves, with concentrations ranging from 0.73 to 15.6 μg/g (dw), but only limited translocation (<5%) to roots. After feeding on 5 mg/L 2H-PSNP-contaminated lettuce leaves for 14 days, snails accumulated NPs at 0.33 to 10.7 μg/kg (dw), with an overall kinetic trophic transfer factor of 0.45, demonstrating trophic dilution in this food chain. The reduced ingestion rate of 3.18 mg/g/day in exposed snails compared to 6.43 mg/g/day can be attributed to the accumulation of 2H-PSNPs and elevated levels of chemical defense metabolites in the lettuce leaves, which decreased the palatability for snails and disrupted their digestive function. This study provides critical quantitative information on the characteristics of airborne NP bioaccumulation and the associated risks to terrestrial food chains.

3D Porous Silver Nonwoven Mat Prepared with Cellulosic Templates and Spray Equipment for Supercapacitor Current Collectors

Supercapacitors are energy conversion devices with higher power density compared to batteries and higher energy density compared to common capacitors.[1] These particular properties have attracted considerable attention with regard to numerous applications in such diverse fields as power electronics, military equipment, and hybrid electric vehicles (i.e. HEVs, in order to help the stop and go function and to provide peak power for improved acceleration).[2] In addition, supercapacitors can play an important role in complementing the energy storage functions of batteries and fuel cells by providing back-up power supplies to protect against power disruptions.[3,4]Supercapacitors have four major components, namely, current collectors, electrodes, electrolytes and separators.[3] However, although electrodes have been actively studied, there are far fewer studies of current collectors than the other there components. Typical current collectors are nickel (Ni), platinum (Pt), gold (Au), aluminum (Al), silver (Ag) and copper (Cu). Although Ag compared with the other materials offers many advantages including high current-carrying capability (i.e., lowest resistivity at 1.63 x 10-8 Ωm)[5] and good chemical and thermal stability,[6] Ag current collectors are rarely used in supercapacitors. In our previous study, which demonstrated the usefulness of a solution processed Ag current collector in supercapacitors, we used a 2-dimensional (2D) Ag plated polymer film as the current collectors.[7] In this study, we propose a method of enhancing the usefulness of a solution processed Ag current collector by making a 3-dimensional (3D) porous Ag nonwoven mat current collector from the cellulosic template in order to maximize the efficiency of the Ag current collector. This may have the result of maximizing the contact area between the electrode and the electrolyte, such as Ni foam.[8] This 3D porous Ag nonwoven mat would be also useful in such applications as the cathodes of alkaline fuel cells owing to its good chemical and thermal stability,[9] and might also be used in a variety of filtration applications where the antimicrobial and antibacterial properties of silver make silver membranes a very efficient filtration system.[10]In this study, we propose a simple method of making a 3D porous silver nonwoven mat as the current collector of supercapacitors, and investigate their super-capacitive properties using cyclic voltammetry in 1 M Na2SO4. For the purpose of comparison, the electrochemical properties of the 2D Ag plated current collector were also investigated. Cellulosic templates were used to make a 3D porous Ag nonwoven mat as the current collector of a supercapacitor with an Ag nanoparticle dispersed solution and simple spray equipment.

Preparation of W-Cu submicrometer composite powder by spray solution combustion synthesis-hydrogen reduction

Preparation of W-Cu submicrometer composite powder by spray solution combustion synthesis-hydrogen reduction

Application of the theory of planned behavior to model the intention and behavior of tomato growers in pesticide exposure

Widespread and indiscriminate use of pesticides has become one of the most important environmental and public health problems around the world. This study was conducted with the aim of applying the theory of planned behavior model to investigate the knowledge, attitude, and behavior of tomato growers in the face of pesticides in agricultural lands located in Kurdistan province, western Iran. We included 300 tomato growers in this study and they filled up a standard TPB questionnaire containing questions about basic information, knowledge, attitude and behavior about pesticides and their actions for disposing of the residual spray solution, washing place of pesticide sprayer, and the disposal of water from washing the equipment. Most of the respondents, 86.7 %, had not participated in promotional classes on how to dispose of the residual solution. Approximately 46.15, 38.46, and 15.39 % of pesticides contained moderately toxic, slightly toxic and practically non-toxic compounds, respectively. More than two-thirds (89 %) of the tomato growers stated that they leave the water from washing the equipment in the field. In addition, among the three variables of TPB, attitudes had the highest score (3.38), which indicated the positive to relatively neutral attitude of farmers towards the safe use of pesticides. These findings can be useful for planners and environmental organizations to make effective interventions to reduce environmental pollution caused by pesticides. Since the incorrect use of pesticides is one of the important environmental and health factors, education and awareness programs can help farmers to consider the correct use of pesticides and environmental protection more.

Carbon black and polyetherimide modified ES nonwovens for low-cost and continuous seawater desalination

Solar-powered desalination is considered a promising and sustainable method for producing clean water to alleviate freshwater shortages. However, most solar evaporators have drawbacks such as high costs, complicated processes and lack of durability. Here, we present solar evaporators modified with polyethyleneimine and gallic acid, decorated with carbon black nonwovens, for desalination to produce clean water. The carbon black photothermal nonwovens were produced by treating ES hot air nonwovens with a spray of carbon black solution. Utilizing the light-absorbing heat generation of carbon black and the skin-core structural characteristics of ES(PE/PET) nonwoven, the carbon black is firmly embedded in the PE skin layer of the nonwoven fabric. Subsequently, mussel chemistry inspired the formation of polyethyleneimine and gallic acid coatings on the surface of the carbon black-loaded nonwoven. By combining carbon black with mussel coatings, the photothermal nonwovens demonstrated improved hydrophilicity, excellent photothermal water evaporation performance, and enhanced light conversion efficiency. The modified interfacial evaporator exhibited a high evaporation rate of 1.22 kg m−2·h−1 and had high cost-effectiveness of 332.4 g·h−1·$−1. In addition, reusing, desalination, and outdoor experiments were conducted to showcase the potential of the evaporator for practical desalination. This work demonstrates the significant potential of photothermal ES nonwovens for efficient solar-driven clean water production to tackle global freshwater shortages.

Enhancing π-SnS thin films and fabrication of p-SnS/n-Si heterostructures through flow rate control in ultrasonic spray pyrolysis for improved photovoltaic performance

This study presents findings related to the characterization of cubic SnS (π-SnS) thin films and p-SnS/n-Si heterojunction structures produced simultaneously using the ultrasonic spray pyrolysis technique. In this context, the impact of different spray solution flow rates on the morphological, structural, optical, and electrical characteristics of the films was examined. Morphological analyses revealed that higher flow rates resulted in films with denser and smoother surfaces, approximately 6 nm in roughness. Additionally, it was observed that both the thickness and the growth rate of the films could be adjusted through the modulation of the flow rate. Structural analyses determined that the crystallite size increased and micro-strain values decreased with increasing flow rates. Optical evaluations indicated a decline in the optical band gap of the thin films from about 1.8 eV to 1.7 eV as the flow rates increased. This trend was consistently observed in the data obtained using the Tauc method and the derivative of transmission with respect to wavelength versus photon energy graphs. Electrical analyses revealed that the resistivity values of the thin films increased from 5.24 × 105 Ωcm to 1.64 × 106 Ωcm with increasing flow rates. Furthermore, I-V analyses of the Au/p-SnS/n-Si/Ag heterojunction structures indicated significant variability in key electrical properties. The saturation currents displayed a broad range, suggesting varying efficiencies in charge carrier collection across different samples. Similarly, the change of ideality factors pointed to differences in charge transport mechanisms, while the shifts in barrier heights indicated changes in junction properties with different fabrication conditions. The results of this study offer valuable perspectives for future research.

Anti-Corrosion SiOx-Doped DLC Coating for Raster Steel Linear Scales

In this study, we investigated the efficacy of SiOx-doped diamond-like carbon (DLC) films for enhancing the corrosion resistance of raster steel linear scales. The research work highlights the significant role of DLC film materials in enhancing corrosion resistance, making them a promising solution for various industrial applications. The Raman spectroscopy analysis of SiOx-doped DLC films, synthesized via a direct ion beam technique with HMDSO vapor, revealed prominent D and G bands characteristic of amorphous carbon materials, with a high degree of disorder indicated by an ID/IG ratio of 1.85. X-ray diffraction patterns confirmed the amorphous nature of the SiOx-doped DLC films and the minimal impact of the DLC deposition process on the underlying crystalline structure of steel. UV–Vis-NIR reflectance spectra of SiOx-doped DLC on stainless steel demonstrated improvements in the blue wavelength region compared to stainless steel with ripples alone, which is beneficial for applications utilizing blue light. Corrosion tests, including immersion in a 5% salt solution and salt spray testing, showed that SiOx-doped DLC-coated stainless steel exhibited superior corrosion resistance compared to uncoated steel, with no significant signs of corrosion observed after extended exposure. These findings underscore the potential of SiOx-doped DLC coatings to provide long-term corrosion protection and maintain the structural integrity and surface quality of steel components in harsh environments.

Variation in Grain Yield Losses Due to Fall Armyworm Infestation among Elite Open-Pollinated Maize Varieties under Different Levels of Insecticide Application

Maize is an important food and industrial cereal crop that serves as the main source of energy for millions of low-income people in sub-Saharan Africa (SSA), but its production and productivity are constrained by many constraints, among which the fall armyworm (FAW) is the major one. The use of insecticides is the most effective control measure for the FAW. However, excessive use of chemical insecticides has environmental and health implications, and it can be expensive for resource-poor farmers. The objective of this study was to evaluate the extent of variation in yield losses due to the FAW among some elite maize open-pollinated varieties (OPVs) under two levels of insecticide application and control (0 application). In a two-year field study, 10 elite maize OPVs were evaluated under two levels of emamectin benzoate (5% WDG) applications and the control: 75 and 150 mL of spray solution per 20 L of water. The experimental design was a randomized complete block with three replications. The data were collected on grain yield (GY) and FAW leaf damage rating (LDR). The LDR was conducted on a 1–9 scale and used to categorize the maize varieties as resistant (1–4), moderately resistant (4–6), and susceptible (6–9). Significant varietal differences were obtained for GY and LDRs. The GY of the varieties under control (0 mL), 75 and 150 mL insecticide applications ranged from 3.3 t ha−1 (DTSTR-Y SYN-13) to 4.6 t ha−1 (PVA SYN-3), from 4.5 t ha−1 (DTSTR-Y SYN-13) to 6.4 t ha−1 (PVA SYN-13), and from 4.2 t ha−1 (DTSTR-Y SYN-13) to 6 t ha−1 (DTSTR-Y SYN-14), respectively. No significant differences in GY were found between the application of 75 and 150 mL of insecticide application. The relative loss in GY among the varieties under control (0 mL) differed with an increase in the level of insecticide application. The relative GY loss at the 75 mL insecticide application ranged from 18% (PVA SYN-3) to 38% (DTSTR-Y SYN-15) with a mean of 27%, whereas at the 150 mL insecticide application, it varied from 13% (PVA SYN-3) to 42% (DTSTR-Y SYN-15), with a mean of 26%. All the varieties exhibited moderate resistance to FAW, except DTSTR-Y SYN-14, which was susceptible. The varieties PVA SYN-3 and PVA SYN-13 were the most consistent in GY across the three insecticide treatment levels. The mean performance of the varieties for FAW leaf damage ranged from 4.0 (SAMMAZ-15) to 6.2 (DTSTR-Y SYN-14), from 4.5 (SAMMAZ-15) to 6.3 (PVA SYN-6), from 4.5 (SAMMAZ-15) to 6.3 (DTSTR-Y SYN-14), and from 3.5 (SAMMAZ-15) to 5 (DTSTR-Y SYN-14) for LDR 1, LDR 2, LDR 3, and LDR 4, respectively. The use of moderately resistant varieties, combined with timely spraying of emamectin benzoate at 75 mL provided adequate management for the FAW infestation and sustained high maize grain yield.

Efficiency of reduced rates of 2,4-D in mixture with wood vinegar in weed control

Chemical control is the most efficient method in weed management. However, given the societal demand for reducing pesticide use and mitigating production costs, alternatives for reducing herbicide doses should be considered. Among the alternatives that can contribute to the sustainable management of weeds is wood vinegar, a bio-input that has several applications in agriculture. In light of this, the objective of this study was to evaluate the reduction of doses of 2,4-D herbicide by mixing it with wood vinegar (WV). The experiments were conducted in a greenhouse at the Campus of Engineering and Agricultural Sciences (CECA/UFAL). The experimental design was completely randomized in a 4x2 factorial scheme, with 4 herbicide-WV mixtures (Distilled water; 0.5 L ha-1 of 2,4-D + 1 L ha-1 of WV; 1 L ha-1 of 2,4-D + 0.5 L ha-1 of WV; and 1.5 L ha-1 of 2,4-D (recommended commercial dose), and the spray solution with water only and with mineral oil (0.5% v/v). The receptor plants were Crotalaria juncea, Senna obtusifolia, and Bidens spp., and each weed species constituted an experiment, where phytotoxicity scale, control (%), and relative dry mass (%) were evaluated. The reduction of 2,4-D doses was not effective in controlling Crotalaria juncea, which showed satisfactory control only at the commercial dose of the product with mineral oil. The species Senna obtusifolia and Bidens spp. were effectively controlled in all treatments of the experiments regardless of mineral oil.

Tank-mix adjuvants improved spray performance and biological efficacy in rice insecticide application with unmanned aerial vehicle sprayer.

The use of unmanned aerial vehicles (UAVs) for the application of plant protection products (PPPs) in paddy fields is becoming increasingly prevalent worldwide. Despite its growing usage, UAV spraying for rice pest control faces practical challenges, including limited canopy penetration, uneven deposition, and significant spray drift. This study investigated the impact of two tank-mix adjuvants, Wonderful Rosin (Adjuvant-1) and Tiandun (Adjuvant-2), at six volume concentrations, on the spray liquid's physicochemical properties, spray drift, plant deposition, and the biological efficacy of rice insecticides using a quadrotor UAV sprayer. The physicochemical characteristics of the spray liquid influenced spray performance and biological efficacy. Incorporating Adjuvant-1 and Adjuvant-2 led to a decrease in surface tension and contact angle while increasing the viscosity of the spray solution. These alterations in surface tension and viscosity contributed to an optimized droplet size distribution, reduced spray drift, enhanced deposition uniformity and penetration, and improved control efficacy against the rice planthopper in UAV applications. The highest control efficacy was observed at a concentration of 0.5%, showing an improvement of 35.12% (Adjuvant-1) and 20.23% (Adjuvant-2) over applications without tank-mix adjuvant 7 days after treatment. The judicious selection of tank-mix adjuvants for UAV PPP applications can significantly enhance spray performance and biological efficacy in controlling rice insects. This study's findings offer valuable insights for integrating tank-mix adjuvants into UAV spraying applications. © 2024 Society of Chemical Industry.

Synthesis and toxicity evaluation of a spray consisting of silver nanoparticles, ethylenediaminetetraacetic acid, methylsulfonylmethane, and xylitol on vero cell line

Abstract Introduction: Dental plaque is a biofilm or an accumulation of bacteria that grows in the internal surfaces of the mouth and can be observed as a white to pale yellow layer over or between teeth. The continuous formation and accumulation of dental plaque lead to oral diseases. As a result, it is necessary to prevent the aggregation of dental plaque and clean it daily. Recently, ethylenediaminetetraacetic acid (EDTA) has been utilized in toothpaste to prevent plaque formation as an EDTA-transporting enhancer, methylsulfonylmethane (MSM) can effectively increase its local effect. Xylitol decreases the Streptococcus mutans count by changing the metabolic pathways. Aims: In the present study, we synthesized a solution containing silver nanoparticles, EDTA, MSM, and xylitol and evaluated its toxicity on the Vero cell line through the MTT assay. Materials and Methods: To produce silver nanoparticles, we dissolved silver nitrate in sodium citrate. Then we used a solution of distilled water and polyvinylpyrrolidone, which resulted in the encapsulation and stabilization of silver nanoparticles, and the solution was made by mixing other ingredients. We evaluated the cytotoxicity of this spray using the Vero cell line. We cultured the cells in the 10% FBS-containing RPMI culture medium. For performing the cytotoxicity test, we put 10,000 cells in each well of the 96-well plate, and the next day added the synthesized solution to each well at dilutions 0.05%, 0.1%, 0.2%, 0.5%, 1%, 2%, 5%, and 10%. As the control group, we used 4 wells containing live Vero cells without adding the solution. After 24, 48, and 72 h, we added the MTT solution to each well and incubated the plates at 37°C for 4 h. Finally, we evaluated the rate of living cells by reading the absorbance with an ELISA device at 570 nm. Results and Discussion: We used the Mann–Whitney nonparametric test to evaluate the cytotoxicity of different concentrations of the synthesized spray solution and compare the cell viability rate of groups with the controls in various periods. According to the cytotoxicity results of different concentrations of the spray solution on the Vero cell line, there was no significant difference in cytotoxicity between the 0.05%, 0.1%, 0.2%, and 0.5%, and control groups at 24, 48, and 72 h (P &gt; 0.05). No significant difference existed in cytotoxicity between 1% and 2% concentrations and the controls 24 h after exposure; this became significant after 48 and 72 h (P = 0.014). However, a significant difference existed in cytotoxicity between 5% concentration and the controls 24, 48, and 72 h after exposure (P = 0.014). The CC50 of the spray solution was calculated at 3.51%. Conclusion: The findings of this study showed that the synthesized solution is nontoxic; therefore, this spray solution can be used safely as an oral mouthwash and spray.

A randomized, double-blind study to compare the efficacy and safety of nalbuphine nasal spray and injectable solution in patients after orthopaedic interventions and traumatological procedures.

Our previous 3-period crossover study in healthy volunteers comparing the pharmacokinetics of nalbuphine nasal spray Apain with parenteral nalbuphine solution demonstrated high bioavailability of the nasal spray and close similarity of pharmacokinetic profiles after intranasal and intramuscular administration, especially within 30 min postdose. The aim of the present study was a noninferiority assessment of nalbuphine nasal spray vs. intramuscular injection for pain relief in postoperative patients. Ninety orthopaedic and traumatology patients were enrolled in this double-blind, randomized study of the effectiveness and tolerance of a single 10.5mg dose of nalbuphine nasal spray vs. 10mg intramuscular injection. The summed pain intensity difference (SPID0-6) calculated using visual analogue scale scores was the primary study endpoint. Of 90 subjects enrolled, the per-protocol efficacy population comprised 79 patients; 6 patients in the reference group and 5 patients in the test group were excluded due to remedication. The mean values of study endpoints with 95% confidence interval were as follows in reference and test groups, respectively: SPID0-6= 228.08 (205.73-250.43) vs. 248.73 9 (225.83-271.63), time to pain relief onset =0.28 h (0.25-0.31) vs. 0.27 h (0.25-0.29), duration of analgesia =5.55 h (5.17-5.93) vs. 5.51 h (5.10-5.92), area under the curve = 119.30 (91.17-147.43) vs. 99.81 (74.52-107.10). No statistically significant differences were revealed. Nalbuphine nasal spray Apain has been proven to be a safe, noninvasive alternative to intramuscular nalbuphine to relieve severe postoperative pain. Designed for self-administration and dose-adjusting, the noncontrolled opioid analgesic nalbuphine spray can be used for patient-controlled analgesia in out-of-hospital, field and home settings.

Energy efficiency analysis of novel combined open absorption multifunctional heat pump and FlashME desalination system with a compressed air dryer

Energy intensive thermal desalination and compressed air-drying processes coupled with low grade heat recovery units can significantly contribute to carbon and energy footprint reduction. In this paper, a novel combined system based on an open absorption multifunctional heat pump and FlashME desalination system with a compressed air dryer is proposed to recover the latent heat from flue gas and efficiently utilize it to drive the desalination process for seawater treatment and supply the compressed dry air. The energy performance of the combined system is analyzed under the effect of various key operational parameters by simulating the validated process model. The results of energy analysis indicate that the novel system can recover the latent waste heat from flue gas with an efficiency of 83.02 % and supply the compressed dry air at low humidity of 1.41 g/kg by operating at a thermal COP of 1.95. Furthermore, the system can efficiently utilize the recovered low-grade heat to produce freshwater at a recovery rate of 23.14 %. The findings of the critical performance analysis show that the drying, and latent heat recovery performance of the coupled system is dependent mainly on the inlet parameters of the spray solution and the flue gas humidity. However, the water recovery of FlashME is totally dependent on heat capacity and the regeneration pressure such that the performance ratio increases from 1.51 to 4.03 by operating with hot seawater of 60–80 °C, when the regeneration pressure is raised up to 53.48 kPa. Moreover, the coupled system configured in parallel double stage can lower 11.43–37.78 % regeneration load along with 54.24 % improvement in distillate productivity when the operating pressure is raised up to 800 kPa and the rise in airflow rate in dryer can decrease the 10.41–52.45 % regeneration load on external heat source.

Recognition of concrete microcrack images under fluorescent excitation based on attention mechanism deep recurrent neural networks

This study aims to recognize fluorescent excitation images of microcracks in concrete components through the adoption of an Attention Mechanism-based Deep Recurrent Neural Network (RNN) model, thereby enhancing the accuracy and efficiency of crack detection. Considering the significance of concrete crack detection and the limitations in efficiency and accuracy of existing methods, this paper proposes an innovative image processing technique that combines fluorescent excitation methods with deep learning models to achieve earlier and more accurate identification of concrete microcracks. C30 concrete specimens were prepared experimentally and treated with fluorescent solution spray. Fluorescent images of cracks under UV light excitation were collected and processed using a segmented attention mechanism deep RNN model. Various performance evaluation metrics, including mean Intersection over Union (mIoU), mean Image Intersection over Union (miIoU), mean Image Dice Coefficient (miDice), and F1 score, were employed to comprehensively assess the model's performance. The results demonstrate that the proposed model achieved significant effectiveness in concrete crack image recognition, showing higher mIoU, miIoU, miDice, and F1 scores compared to other representative deep learning models, thus proving its advantages in recognition accuracy and efficiency. Particularly, by introducing the segmented attention mechanism, the model could capture microcrack features more effectively, significantly improving the accuracy of crack identification. This method not only provides a new technical approach for the early detection of concrete cracks but also lays the foundation for further development of efficient and accurate crack detection technologies to accommodate more complex engineering application scenarios.