High volume applications

Case and carton sealing is a high volume application for hot melt adhesives. Typical formulas use 20-30% wax, 25-40% polymer, and 35-55% tackifier resin. The basic requirements for packaging adhesives will be described followed by formulating guidelines for specific market areas. The focus of this discussion will be on EVA and EnBA-based systems, which are the most common. 

Gas separation Hollow-fibre for high-volume applications with low-flux, low-selectivity membranes in which concentration polarisation is easily controlled (nitrogen from air) Spiral-wound when fluxes are higher, feed gases more contaminated, and concentration polarisation a problem (natural gas separations, vapour permeation). 

De Vreede, J.A.F., De Haan, M., Brouwer, D.H., van Hemmen, J.J., and de Kort, W.L.A.M. (1994) Exposure to Pesticides. Part III. High-Volume Application to Chry-santemums in Greenhouses, Report S131-4, Ministry of Social Affairs and Employment, The Hague, The Netherlands. 

Tank-mix samples were taken prior to each application to determine actual spray concentration. For high-volume applications, the remaining spray liquid was estimated. After completing the low-volume application, the volume of the remaining spray solution was measured and another tank sample was taken. Application rates were calculated from the spray volume, acreage, and concentration of the active ingredient in the tank sample. 

Note HV = high-volume application LV = Low-volume application Tpm = thiophanate-methyl Meth = methiocarb Aba = abamectin. 

The relationship between average ADFR and application rate (AR) was tested using linear regression analysis and the model ADFR = a + b AR. All data concerning high-volume applications (n = 8) and low-volume applications (n = 4) were used, separately or together. The results of these regression analyses are presented in Table 2. 

A possible relationship between DFR and the application rate, as well as the crop volume estimate (CrV), was investigated using a multiple linear regression model (ADFR = a + b AR + c CrV). No significant contribution of crop volume to the variation of ADFR was observed (p = 0.19 and p = 0.87 for high-volume applications and all applications, respectively). 

Dislodgeable foliar residue as a function of time and estimating half-lives of the pesticides after high-volume application... 

The DFR values were followed over a period of 4 weeks from the high-volume application. The decrease of DFR in the two zones was monitored in six greenhouses (three times after application of thiophanate-methyl and three times after application of methiocarb). Figure 2 shows typical log-transformed decays of DFR (average of two samples for each zone) for methiocarb and thiophanate-methyl. Assuming a first-order decay, half-lives were calculated using Equations (3) and (4) and were found to be 29 8.5 days and 11 3.4 days for thiophanate-methyl and methiocarb, respectively. 

The results of the DFR assessment of different crop zones indicate that low-volume applications result in a more homogeneous distribution over the crop compared to high-volume applications. A recent study on the interception of high-volume applications in the cultivation of chrysanthemums revealed interception ratios from 0.2 to 1 related to the leaf area index (LAI) (Veerman et al., 1994). In our study, it was not easy to assess the LAI because of the structure of the carnation crop. Estimation of the LAI based on the results of estimation of the crop density (leaf volume index) was not reliable enough and resulted in a large variance of the calculated interception ratio (from 0.4 up to 5). 

The average value of the transfer factor (approximately 2300 cm2/hr) derived from all data in our study differs somewhat from the transfer factor of 3300 cm2/hr observed in a preceding study during the cultivation of carnations (Brouwer et al., 1992). However, that transfer factor had been derived from data on both high-volume spray (as in the present study) and dusting operations. The powder formulations showed an effective transfer of the residue to the body. Recalculated transfer factors for only high-volume applications showed an average of approximately 2500 cm2/hr. 

Harvesting carnations will account for average transfer factors of about 2000 cm2/hr for pesticides applied by high-volume applications. A critical evaluation of existing data may generate more reliable generic transfer factors for use in the re-entry model. 

Nanocomposites General Motors and Basell Polyolefins continue the development of nanocomposites for high-volume applications in external trim parts such as body panels. Three grades of TPO-based nanocomposites reinforced with 2.5% nanoclay have been commercialized by Basell Polyolefins. The first application of these nanocomposites was a low-volume minivan step option. 

Finally, as robot users develop more familiarity with the capabilities of systems, manufacturers are conceiving and requesting more and more complex applications. Vendors may prefer to select less complex, high-volume applications which may have greater application volume potential. Between these two aspirations, there may develop a presently unfulfilled need for some third party to bridge the gap between what the users would like to have and what the vendors would like to provide. 

For low-volume applications, where cost is a major consideration, organic-coated drums are the preferred material for virtually all applications. For high-volume applications, organic materials are extensively used, due to the fact that they can be readily prepared in a flexible configuration. For mid-volume applications, all three materials are currently in use. 

This type of extrusion blow molding machine uses something called a shuttle machine to get all the parts in place. Alternatively, a rotary machine, illustrated in Figure 14-61, can be used. Rotary extrusion blow molders are used in high volume applications, as in the production of laundry detergent bottles. 

One more factor needs to be considered. Most water is not used for drinking or cooking but for other high-volume applications, such as watering lawns, washing clothes, washing dishes, bathing, and so forth. Furthermore, in today s world, fewer and fewer people drink directly from the tap but rather from bottled water sources. 

The earliest wood adhesive for mass produetion of panels was phenol formaldehyde (PF). This is widely used for products designed to perform in severe weathering eonditions and dominates the exterior plywood market. Resorcinol formaldehyde is a somewhat similar resin system that cures at ambient temperatures, but the cost is much higher, limiting its use in high-volume applications. These systems, although formaldehyde-based, do not have the continuing formaldehyde emission problem that is associated with other formaldehyde-based systems. 

It is impossible to overstate the importance of the role that CFCs have played in making refrigeration, air-conditioning, and, to some extent, aerosols such essential facets of modern existence. Life, as we know it, would be impossible in some parts of the world without the means for cooling food and houses. Of course, the very property that made the CFCs so useful, their stability, allows them to reach the stratosphere and there release chlorine atoms, which interact with the ozone layer. There will be a drastic decline in the use of CFCs in most of their high-volume applications of the heavier CFCs and the volumes will be inconsequential compared to the 2.5 billion pounds of volatile CFCs produced worldwide in 1986. 

The introduction of this process in 1960 resulted in a sharp drop in the price and increase in the supply of world acrylonitrile (Fig. 3), which allowed the discovery of many new high-volume applications in the fibers and plastics industries. 

Quick response over a wide area is also required in migrant pest control, and high volume application rates with water-based sprays are not feasible for inhospitable terrain. 

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