Author: Kelli L. Nelms Publisher: ISBN: Category : Adjuvant Languages : en Pages : 11
Book Description
Many factors, including adjuvants, pesticide formulations, and nozzle tips, affect spray droplet size. It is important to understand these factors as spray droplet size affects both drift and efficacy of pesticides, which is a main concern with pesticide application. A laser particle analyzer was used to determine the spray droplet size and distributions of a range of formulations sprayed through several types of nozzle tips. Nozzles included were extended range flat fan sizes 11003 and 11005 (Spraying Systems XR), air induction flat fan sizes 11005 and 11004 (AI), air induction extended range flat fan size 11005 (AIXR), preorifice flat fan size 11005 (TT), and a second preorifice flat fan size 2.5 (TF). Several deposition/retention adjuvants were studied, including Array, Interlock, In-Place, and Thrust. Another study looked at diflufenzopyr + dicamba (Status, BASF) in combination with several adjuvants. Also, three fungicides were evaluated at differing spray volumes. Results indicated that the droplet size of some nozzle tips is more affected than others by changes in the contents of the spray solution.
Author: Kevin Penfield Publisher: ISBN: Category : Adjuvant Languages : en Pages : 12
Book Description
Drifting of fine droplets during the application of pesticides is an issue of increasing commercial and regulatory importance. Spray drift damages susceptible crops, wastes resources, and results in inconsistent weed control. Several strategies are currently used to mitigate this problem. These include enhanced nozzle technology, improved application techniques, and inclusion of drift control additives in the final tank mix. Elimination of small diameter droplets ("driftable fines") is a key goal. Measurements were made of droplet size distributions of sprayed pesticide formulations containing commercial products representative of the leading drift control technologies, including guar, polyacrylamides, lecithin, and oil/surfactant mixtures. Effects of spray nozzle and pressure were also evaluated. Nozzle technology plays a large role in determining the spray droplet size spectrum. However, there is a strong interplay between nozzle design and formulation variables. We found that drift control agents have greater impact on spray from flat fan nozzles. Also, the ranking of adjuvants depends on the nozzle technology in use: for glyphosate/ammonium sulfate solutions, polymers were more effective in reducing fines from a flat fan nozzle, while surfactant-based products were marginally superior when an air induction nozzle was used. The regulatory community is currently focused on mitigating the generation of small droplets. However, the generation of oversized droplets also effects spray efficacy. The impact of drift control agents on the breadth of the droplet size spectrum is an aspect of drift control which is often overlooked. We found that emulsion-based products tighten the droplet size distribution, while the polymer-based products shift the mean droplet diameter up, broadening the distribution in the process: while the latter effect may earn better ratings from regulatory agencies concerned exclusively with spray drift mitigation, it may be less helpful in enhancing application efficacy.
Author: J. B. Ross Publisher: ISBN: Category : Adjuvants Languages : en Pages : 12
Book Description
Spray droplet size has long been recognized as the most important variable that aerial applicators can influence to mitigate spray drift from the application site. There are several different technologies that are used by researchers to measure droplet size from spray nozzles. The objective of these studies was to determine the influence of eight spray adjuvants on the droplet size spectrum produced by two nozzles in a high-speed wind tunnel when characterized using three different droplet size measurement systems. The adjuvant, nozzles, and airspeeds used in these studies are commonly used by aerial applicators. Three droplet sizing systems (Malvern laser diffraction, PMS optical array probe, and LaVision laser imaging) were simultaneously operated to measure the spray droplet size spectra for each adjuvant, airspeed, and nozzle combination. Two spray nozzles (a D6-46 nozzle and a D2 straight stream nozzle) were evaluated in a high-speed wind tunnel at airspeeds of 45 and 58 m/sec. There were significant differences in the droplet size spectra produced by the eight spray adjuvants tested. There were also significant differences between the droplet size values reported by the three measurement systems (Malvern, LaVision, and PMS) evaluated; however, there was considerable agreement trendwise. In general, the Malvern reported smaller spray droplet size spectra values than the LaVision, while the PMS system generally reported the largest spray droplet size spectra values. These tests are the first reported studies where all three droplet sizing systems were operated simultaneously.
Author: Chester L. Foy Publisher: CRC Press ISBN: 1351425323 Category : Science Languages : en Pages : 382
Book Description
Pesticide Formulation and Adjuvant Technology brings together experts from industry, academia, regulatory offices, and the legal profession to provide a complete and international reference on agrichemical formulations and modern adjuvant technology. Global specialists discuss key topics, from scientific and technical issues to regulatory and legal aspects, including:
Author: L.P. Bayvel Publisher: Routledge ISBN: 1351434950 Category : Science Languages : en Pages : 488
Book Description
Covering the basics of liquid atomization, this book familiarizes readers with the physical processes of liquid atomization, the main types of atomizers and their design, measurements of spray characteristics, experimental investigations of atomizers, and application of atomizers. It demonstrates how to calculate and design atomizers and how to mea
Author: Chenghai Yang Publisher: ISBN: Category : Droplet size Languages : en Pages : 9
Book Description
Rotary atomizers are used in a number of aerial applications, such as forest pest spraying and mosquito control sprays. These types of atomizers have a rotating cage at speeds of 2,000 to 10,000 revolutions per minute (rpm) through which a spray is emitted and atomized. Many applicators routinely add spray adjuvants to change the droplet size, reduce drift potential, or to reduce evaporative effects of a particular spray solution; therefore, six commonly used classes of spray adjuvants were evaluated to determine their effects on droplet size. If an applicator's only concern was minimizing spray drift, the applicator could choose a polymer or high surfactant oil concentrate for helicopter speeds and a polymer for fixed-wing applications. For applicators working under hot, dry conditions where evaporation is a concern, choosing an oil-based adjuvant to help get better coverage by creating smaller droplets that do not evaporate would be recommended. Understanding the role the different adjuvant types play in the final droplet size of the spray is key to successfully setting up and making applications with rotary atomizers.
Author: Chester L. Foy Publisher: CRC Press ISBN: 1351086405 Category : Technology & Engineering Languages : en Pages : 737
Book Description
Based on a conference, this book is intended to promote a better understanding of the effects of adjuvants on pesticide penetration, translocation, photodegradation and stability, spray deposition and dissipation, and the fate of herbicides in the environment.
Author: J. J. C. Picot Publisher: Springer Science & Business Media ISBN: 9780792343714 Category : Nature Languages : en Pages : 234
Book Description
The book deals quantitatively with the generation, dispersion, and deposition of pesticide droplets on vegetation and with off-target drift of undeposited droplets. A computer simulation model of calculating dispersion, deposition, and drift is described with comparisons between calculated results and field measurement results. The model includes the effects of aircraft vortex, atmospheric turbulence, droplet evaporation, and droplet deposition on foliage. Model output includes values of droplet deposit density and size on foliage and ground as well as droplet concentration and size in the drift cloud. In addition, a detailed description of droplet atomizer characterization methods is presented along with a large number of atomizer spectrum results for atomizers in current use. An analysis of a number of forestry spraying innovations is presented. This text is an essential tool in assessing the efficacy and environmental impact of proposed and actual forest spray operations.
Author: JK. Hacker Publisher: ISBN: Category : Bounce chamber Languages : en Pages : 10
Book Description
Tests were conducted with a widely used herbicide (glyphosate) that is available in a range of formulations and a selection of commonly used nozzle types [XR TeeJet, extended range flat spray tip (XR), Turbo TeeJet, wide angle flat spray tip (TT), AI TeeJet, Air Induction spray tip (AI)] and determined the rebound characteristics of each combination using a difficult-to-wet foliar crop target (cabbage), an easy-to-wet hairy weed (velvetleaf), and a difficult-to-wet weed (lambsquarters). The rebound was determined under standard spraying conditions in a track room using a "bounce chamber" constructed at The Laboratory for Pest Control Application Technology (LPCAT). The amount of spray liquid retained and reflected from the leaf surfaces was determined by weight. The data showed that there were no significant differences between the nozzles, but that formulation differences did occur and were a reflection of surfactant level in the spray mixture. There was a significant formulation X leaf interaction and leaf X nozzle interaction, but not a formulation X nozzle interaction.
Author: Kelli L. Nelms
Author: Kevin Penfield
Author: J. B. Ross
Author: Chester L. Foy
Author: L.P. Bayvel
Author: Chenghai Yang
Author: 
Author: Chester L. Foy
Author: J. J. C. Picot
Author: JK. Hacker