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Effects of xanthan gum on atomization and deposition characteristics in water and Silwet 408 aqueous solution

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International Journal of Agricultural and Biological Engineering 2018年第3期11卷 29-34页

作者： Shilin Wang Xiongkui He Jianli Song Shuangshuang Wang Xiaoming Jia Yun Ling Center for Chemicals Application Technology(CCAT) College of ScienceChina Agricultural UniversityBeijing 100193China College of Engineering Huazhong Agricultural UniversityWuhan 430070China College of Engineering China Agricultural UniversityBeijing 100083China

In order to investigate the effects of viscosity on spray formation and utilization of pesticide,different concentrations of xanthan gum(XG)were added into water and 0.1%Silwet 408 aqueous *** size,relative span(RS),fan angle,length of breakup and maximum retention(Rm)were measured with the LU120-02 nozzle spraying under the pressure of 0.3 *** dynamic spreading of the different solutions on maize leaves was tested using a 5μL *** results showed:VMD,RS,length of breakup and Rm went up as the increasing of XG concentration in the range of 0-0.5%with the same solution,while the fan angle of nozzle and spreading area on maize leaf showed the opposite *** 408 could reduce the surface tension of liquid,which could alter the dominant mode of spray formation and lead to earlier sheet breakup,especially in low viscosity *** the same concentration of XG the addition of Silwet 408 could reduce the RS of drop size spectrum but has no effect on VMD or fan *** water solution,there was no difference with different concentrations of XG in the spreading time on maize ***,in the 0.1%Silwet 408 aqueous solution,the spraying time and area were several-fold of that in water with same XG ***,with the same XG concentration,the smaller surface tension liquid indicated lower Rm,and the difference was magnified as the concentration *** work has demonstrated that initial spray characteristics such as droplet size and RS,fan angle,length of breakup,Rm and spreading area can vary depending on the viscosity of spray ***,by transforming the viscosity of the spray liquid to adjust the droplet spectrum to reduce drift,increasing the Rm and spreading area to improve liquid utilization and reduce the usage of pesticides.

关键词： atomization xanthan gum spray droplet size breakup length dynamic spreading

Formulation of self-nanoemulsifying drug delivery systems containing monoacyl phosphatidylcholine and Kolliphor^(■) RH40 using experimental design

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Asian Journal of Pharmaceutical Sciences 2018年第6期13卷 536-545页

作者： Thuy Tran Thomas Rades Anette Müllertz Department of Pharmacy Faculty of Health and Medical Sciences University of Copenhagen Bioneer: FARMA Faculty of Health and Medical Sciences University of Copenhagen

The development of self-nanoemulsifying drug delivery systems(SNEDDS) to enhance the oral bioavailability of lipophilic drugs is usually based on traditional one-factor-at-a-time approaches. These approaches may be inadequate to analyse the effect of each excipient and their potential interactions on the emulsion droplet size formed when dispersing the SNEDDS in an aqueous environment. The current study investigates the emulsion droplet sizes formed from SNEDDS containing different levels of the natural surfactant monoacyl phosphatidylcholine to reduce the concentration of the synthetic surfactant polyoxyl 40 hydrogenated castor oil(Kolliphor ~? RH40). Monoacyl phosphatidylcholine was used in the form of Lipoid S LPC 80(LPC, containing approximately 80% monoacyl phosphatidylcholine, 13% phosphatidylcholine and 4% concomitant components). The investigated SNEDDS comprised of long-chain or medium-chain glycerides(40% to 75%), Kolliphor ~? RH40(5% to 55%), LPC(0 to 40%) and ethanol(0 to 10%). D-optimal design, multiple linear regression, and partial least square regression were used to screen different SNEDDS within the investigated excipient ranges and to analyse the effect of each excipient on the resulting droplet size of the dispersed SNEDDS measured by dynamic light scattering. All investigated formulations formed nano-emulsions with droplet sizes from about 20 to 200 nm. The use of mediumchain glycerides was more likely to result in smaller and more monodisperse droplet sizes compared to the use of long-chain glycerides. Kolliphor~? RH40 exhibited the most significant effect on reducing the emulsion droplet sizes. Increasing LPC concentration increased the emulsion droplet sizes, possibly because of the reduction of Kolliphor~? RH40 concentration. A higher concentration of ethanol resulted in an insignificant reduction of the emulsion droplet size. The study provides different ternary diagrams of SNEDDS containing LPC and Kolliphor ~? RH40 as a reference for form

关键词： Monoacyl phosphatidylcholine Self-nanoemulsifying drug delivery systems D-optimal design Polyoxyl 40 hydrogenated castor oil Kolliphor^(■)(RH40) droplet size Cryogenic transmission electron microscopy

Effects of plant protection UAV-based spraying on the vertical distribution of droplet deposition on Japonica rice plants in Northeast China

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International Journal of Agricultural and Biological Engineering 2021年第5期14卷 27-34页

作者： Yingli Cao Fenghua Yu Tongyu Xu Wen Du Zhonghui Guo Haiyan Zhang College of Information and Electrical Engineering Shenyang Agricultural UniversityShenyang 110866China Liaoning Engineering Research Center for Information Technology in Agriculture Shenyang 110866China State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016China

In order to study the regularity of the vertical distribution of droplet deposition on rice plants during pesticide spraying operated by a low-flying multi-rotor plant protection unmanned aviation vehicle(UAV),water-sensitive spray cards were placed on the leaves at the top,in the middle,and at the bottom of rice plants to acquire data on droplet *** this study,a suspension containing tricylazole and hexaconazole was used in the *** water-sensitive spray cards were analyzed by the droplet deposition processing software iDAS to obtain the vertical distribution of the droplets sprayed by the plant protection *** results showed that (1)significant variation was found in the coverage of the droplets in different vertical positions of the rice *** the effective spray width,the best coverage of the droplets was found in the area just below the rotors,whereas the coverage of areas farther away from the rotors was *** the different vertical positions of the rice plants,the overall droplet coverage was 58.38%at the top,33.55%in the middle,and 11.34%at the bottom of the plants;(2)for all vertical positions,the average size of the droplets ranged between 110μm and 140μm,which was suitable for the control of plant diseases and insect *** highest droplet density was found at the top of the plants,and the distribution of the droplet density was similar in the middle and at the bottom of the rice plants;(3)the diffusion ratio at the top of the rice plants(0.84)was better than that in the middle(0.57)and at the bottom(0.37).The overall relative span could meet the requirements for the actual *** for the position in the middle of the plants,the relative span for the other positions of the plants was over 0.67,which is the standard *** study demonstrated the distribution regularity of droplet deposition along with the vertical direction of rice plants during UAV-based spraying,which is of guiding significance for the u

关键词： plant protection UAV droplet deposition Japonica rice droplet size vertical distribution spraying Northeast China

Solvent Extraction in Hydrometallurgy: Present and Future

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Tsinghua Science and Technology 2006年第2期11卷 137-152页

作者： Gordon M. Ritcey G. M. Ritcey and Associates Inc. Ottawa Canada

During the past 10 years, there have been incremental advances in the application of solvent extraction to process hydrometallurgy. The most cited areas in the literature include chemistry, chemical engineering, pilot plants, and plant operation. Within these areas, there were considerable interest in synergism, diluents, degradation, contactors, surfactants, hydrometallurgical applications, environmental and secondary applications, and health and safety. The summary to the present is followed by a prediction for the future in the above areas of interest. These include the use of speciation; improved understanding of the role of surfactants on the system; optimization through modelling, pilot plants, and contactor selection; improvements in plant operation; further new applications; and plant safety. The review has indicated that considerable knowledge is now available to optimize and improve on process design and plant applications.

关键词： chemical engineering coalescence degradation diluents dispersion droplet size electrostaticpseudoliquid membrane environmental and secondary recovery hydrometallurgical applications

Experimental investigation on the spray characteristics of agricultural full-cone pressure swirl nozzle

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International Journal of Agricultural and Biological Engineering 2023年第4期16卷 29-40页

作者： Xiuyun Xue Xufeng Xu Shilei Lyu Shuran Song Xin Ai Nengchao Li Zhenyu Yang Zhen Li College of Electronic Engineering(College of Artificial Intelligence) South China Agricultural UniversityGuangzhou 510642China National Citrus Industry Technical System Machinery Research Office Guangzhou 510642China Engineering Research Center for Monitoring Agricultural Information of Guangdong Province Guangzhou 510642China Meizhou SCAU-Zhensheng Research Institute for Modern Agricultural Equipment Meizhou 514781China

The spray characteristics of a full-cone pressure swirl nozzle have been investigated in this *** results were defined by Reynolds number,which focuses on the breakup of liquid film,droplet size,velocity,and liquid volume flux under different Reynolds numbers at the near-field *** spray structure was visualized using a high-speed camera,and the characteristics of droplets were measured using a Phase Doppler Anemometer(PDA)in both the radial and axial *** tests were carried out at varying spray pressures(0.2 to 1.0 MPa),corresponding to different Reynolds numbers(5369 to 12006).It was found that when the Reynolds number rises,the liquid became more unstable after leaving the nozzle,causing the liquid film to break up *** to the measurements of PDA,the coalescence of droplets increased due to the centrifugal ***’s more,the velocity of the droplets fluctuates significantly in the radial direction,and the droplets with a smaller particle size had a higher average *** the perspective of liquid distribution,the increase in Reynolds number caused the spray liquid to move in the radial direction *** contrast,the liquid volume distribution changed in the radial direction more obviously than in the axial direction,growing to the maximum along the radial direction and gradually *** can provide a reference for selecting operating parameters for actual agricultural spray operations and the design of electrostatic nozzles through the research on breakup and droplet characteristics.

关键词： full-cone pressure swirl nozzle droplet size droplet velocity liquid volume flux high-speed camera PDA

Hydraulic performance characteristics of impact sprinkler with a fixed water dispersion device

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International Journal of Agricultural and Biological Engineering 2018年第6期11卷 104-112页

作者： Zakaria Issaka Hong Li Yue Jiang Pan Tang Chao Chen Ransford Opoku Darko Research Center of Fluid Machinery Engineering&Technology Jiangsu UniversityZhenjiang 212013JiangsuChina Department of Agricultural Engineering Tamale Technical UniversityNorthern RegionGhana Department of Agricultural Engineering University of Cape CoastCentral RegionGhana

One way to adapt to the trend towards low-energy and to improve the hydraulic performance of the impact sprinkler under a low pressure condition is by means of a fixed water dispersion device.A fixed dispersion device disperses jet flow from the nozzle *** shape of the tip,impact angle(θ),diameter(D),and depth in the jet flow(d)have significant influence on the hydraulic *** this study,the hydraulic performance characteristics of impact sprinkler as affected by the fixed water dispersion device were studied under indoor *** water distributions from the sprinkler were obtained by experiments for the fixed water dispersion *** was used to transform the radial data into net data,and the uniformities were simulated in a square layout from 1 to 2 times the range(R).The droplet size distributions from the fixed water dispersion devices were measured by a laser precipitation monitor(LPM).Results showed that the range increased with the increase of pressure,and the sprinkler with type C_(2) produced a rectangular-shaped water distribution pattern,while the range was maintained.A maximum uniformity of 71.56%,75.56%,77.23%,73.32%,78.88%and 86.67%was found for types A1,B1,C1,A2,B2,and C_(2),respectively under a pressure of 200 *** uniformity from the sprinkler using type C_(2) surpassed 80%,while type C1 fell *** sizes from type C_(2) was best,and the mean droplet diameter decreased with the increase of ***,type C_(2) can be selected for further optimization of the design features to improve the hydraulic performance of the impact sprinkler under low pressure conditions.

关键词： fixed water dispersion device impact sprinkler range water distribution uniformity droplet size

Drift potential of UAV with adjuvants in aerial applications

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International Journal of Agricultural and Biological Engineering 2018年第5期11卷 54-58页

作者： Xiaonan Wang Xiongkui He Jianli Song Zhichong Wang Changling Wang Shilin Wang Ruochen Wu Yanhua Meng College of Science China Agricultural UniversityBeijing 100193China Quanfeng Aviation Plant Protection Technology Co. Ltd.Anyang 455001China

The reduction of pesticide aerial spraying drift is still one of the major challenges in modern *** aim of this study was to evaluate the drift potential of different types of unmanned aerial vehicle(UAV)and adjuvant products for reducing spray drift in aerial *** types of UAV(3WQF120-12 and 3CD-15 fuel oil powered single-rotor UAV and HY-B-15L battery powered single-rotor UAV)were selected in this study with regular application parameters to compare each spray drift,and 3WQF120-12 fuel oil powered UAV was selected to quantify spray drift of 6 adjuvants dissolved in water under field *** were marked with brillant sulfoflavin dye(BSF)at 0.1%.Petri dishes and rotary impactors were used to collect airborne and sediment drift,*** deposits were evaluated by spectrophotometry in order to quantify *** results showed that when the flight height was 1.5-2.0 m above the crop at the flight speed of 4-5 m/s and the average wind speed of 1.63-1.73 m/s,3WQF120-12 fuel oil powered UAV had lower drift potential than the other two types;DV0.5 and percentage of droplets with diameter≤75μm had very significant effects on spray drift percentage(p=0.01);the risk of drift in agricultural spraying could be significantly decreased not only by reducing the percentage of fine droplets but also by changing droplet *** to water,Silwet DRS-60,ASFA+B,T1602,Break-thru Vibrant,QF-LY and Tmax could reduce by 65%,62%,59%,46%,42%,and 19%spray drift,*** water without adjuvants were sprayed,90%of drift droplets were located within a range of 10.1 m of the target area while with 0.8%Silwet DRS-60 adjuvant in water,the distance was shortened to 6.4 m.

关键词： spray drift UAV adjuvant aerial application drift potential evaluation droplet size

Comparison of droplet distributions from fluidic and impact sprinklers

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Frontiers of Agricultural Science and Engineering 2015年第1期2卷 53-59页

作者： Xingye ZHU Shouqi YUAN Junping LIU Xingfa LIU National Engineering Research Center of Pumps and Pumping System Jiangsu University Research Center of Fluid Machinery Engineering and Technology Jiangsu University

To adapt to the trend toward low-energy precision irrigation, the droplet distributions for two new prototype sprinklers, outside signal sprinkler(OS) and fluidic sprinkler(FS), were compared with impact sprinkler(IS). A laser precipitation monitor was used to measure the droplet distributions. droplet size and velocity distributions were tested under four operating pressures for nozzles 1.5 m above the ground. For the operating pressures tested, the mean OS, FS and IS droplet diameters ranged from 0 to 3.4, 0 to 3.5, 0 to 4.0 mm, *** mean OS and FS droplet velocities ranged from 0 to6.3 m$s–1, whereas IS ranged from 0 to 6.3 m$s–1. Being gas-liquid fluidic sprinklers, droplet distributions of the OS and FS were similar, although not identical. IS mostly produced a 0.5 mm larger droplet diameter and a 0.5 m$s–1greater velocity than OS and FS. A new empirical equation is proposed for determination of droplet size for OS and FS, which is sufficiently accurate and simple to use. Basic statistics for droplet size and velocity were performed on data obtained by the photographic methods. The mean droplet diameter(arithmetic, volumetric and median)decreased and the mean velocity increased in operating pressure for the three types of sprinkler.

关键词： outside signal sprinkler fluidic sprinkler impact sprinkler sprinkler irrigation droplet size droplet velocity

How Much Do Adjuvant and Nozzles Models Reduce the Spraying Drift? Drift in Agricultural Spraying

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American Journal of Plant Sciences 2017年第11期8卷 2785-2794页

作者： Fabiano Griesang Ricardo Augusto Decaro Cícero Antonio Mariano dos Santos Eduardo Souza Santos Nelson Henrique de Lima Roque Marcelo da Costa Ferreira Nucleus of Study and Development at Technology of Application—NEDTA Sao Paulo State University(Unesp)School of Agricultural and Veterinarian SciencesJaboticabal CityBrazil

The spraying of herbicides in crops has become the main form of weed control. Although it means unexpected effects on non-target plants resulted by spraying drift. Thus, improvements in application techniques, as the best selection of spray nozzles and adjuvant, are essential to avoid environmental contamination and economic losses. On this work, we evaluate how much adjuvant associated with nozzles can reduce the spray drift. The nozzles used at experiment were air induction flat tip, hollow cone and twinjet and the spray liquids, which were composed of herbicide glyphosate and phosphatidylcholine + propionic acid adjuvant. Measurements were made at wind tunnel and droplet sizer, at laser diffraction method. The models of nozzles influence in droplet size characteristics and in occurrence of spray drift. The use of adjuvants reduces the spray drift only combined with the twinjet nozzle, while for the other models the adjuvant did not reduce the global spray drift at significant levels. The adjuvant reduced the spray drift until 39%, while the nozzles model reduced until 74%. Both techniques when combined were able to reduce until 80%. The model of nozzle has the biggest result on drift mitigation and the use of adjuvants can increase the drift mitigation specially with nozzles that produces smallest droplets.

关键词： droplet size Uniformity of droplets Span Volumetric Median Diameter Safe Application