Turfs

Artificial kidney dialyser Artificial turf Artimte [12143-96-3] Artists colors Arvin [9046-56-4]... 

PLATO Plattnerite Platyhelminths Playfield Turf Plazjet Plectonema Plegine Pleochroism Pleurisy... 

In the United States the analytical methods approved by most states are ones developed under the auspices of the Association of Official Analytical Chemists (AOAC) (3). Penalties for analytical deviation from guaranteed analyses vary, even from state to state within the United States (4). The legally accepted analytical procedures, in general, detect the solubiUty of nitrogen and potassium in water and the solubiUty of phosphoms in a specified citrate solution. Some very slowly soluble nutrient sources, particularly of nitrogen, are included in some specialty fertilizers such as turf fertilizers. The slow solubihty extends the period of effectiveness and reduces leaching losses. In these cases, the proportion and nature of the specialty source must be detailed on the labeling. 

Metal Organics and Inorganics. The metal organic herbicides are arsenicals used for the selective, post-emergence control of grass and broadleaved weeds in cropland and noncroplands. These herbicides are particularly usehil for weed control in cotton and turf crops (2,296,294). CacodyUc acid is a contact herbicide used for nonselective weed control in cropland and noncropland (299). Ammonium sulfamate [7773-06-0] (AMS) is an inorganic herbicide used for control of woody plants and herbaceous perennials (2). 

Horticultural appHcations include use of greenhouse thermal screens, rowcrop and turf covers, conveyer belts to process agricultural products, and other similar items. High performance fibers are not normally used in these appHcations, but high strength fibers are preferable for conveyer belts. Environmentally inert low cost fibers such as polypropylene are used for many of the outdoor horticultural appHcations. 

For the preparation of mixtures of mercurous and mercuric chlorides used to control turf-fungus diseases, the precipitated product of the second method may be mixed with the required amount of mercuric chloride. Alternatively, the chamber material, if the ratios of mercurous and mercuric chloride are correct, may be used directiy. 

A grass-like artificial surface was installed for the first time in 1964, at Moses Brown School (Providence, Rhode Island) (1). In 1966, artificial turf was installed in the Houston Astrodome in Texas. These surfaces consisted of green pigmented, nylon-6,6 pile ribbon, with a cross-section resembling that of natural grass. Since that period, other fabrics of various pile ribbon and constmctions have continued to become available commercially for indoor and outdoor facihties. 

Other more recent examples of recreational surfaces or components are artificial turf variations for golf tee mats and croquet, permanent resident base layers replacing asphalt or asphalt and shock-absorbing underpad in artificial turf field instadations, and sand-fided turf... 

These grass-like and resident instadations require substantial amounts of synthetic materials. A typical sports field covered with artificial turf requires approximately 15,000 kg of fabric, 15,000—30,000 kg of shock-absorbing underpad, and 5,000—10,000 kg of adhesive and seaming materials. The artificial surface for a 0.40-km miming track may require 50,000—70,000 kg of materials. Paint striping and marking of turf, tracks, and courts cad for additional materials. 

Recreational surfaces must provide certain performance characteristics with acceptable costs, lifetimes, and appearance. Arbitrary but useful distinctions may be made for classification purposes, depending on the principal function a covering intended primarily to provide an attractive surface for private leisure activities, eg, patio surfaces a surface designed for service in a specific sport, eg, track surfaces or a grass-like surface designed for a broad range of heavy-duty recreational activities, including professional athletics, eg, artificial turf for outdoor sports. 

Typical static friction coefficients are given in Table 1. These data demonstrate that the absolute traction values for synthetic surfaces are satisfactory in comparison with natural turf, provided that shoes with the appropriate surfaces are employed. Synthetic surfaces by virtue of their constmction are to a degree directional, a characteristic which, when substantial, can significantly affect both player performance and ball roU. This effect is evident in a measurement of shoe traction in various directions with respect to the turf—pile angle. Some traction characteristics are directiy affected by the materials. 

Foi example, nylon pile fabrics, exhibiting higher moisture regain, have different traction characteristics under wet and dry conditions than do polypropylene-based materials. Effects of artificial turf fabric constmction on shoe traction ate given in Table 2. Especially effective in aiding fabric surface uniformity is texturing of the pile ribbon, a process available for the two principal pile materials nylon and polypropylene. 

By way of comparison, for natural grass playing fields in late autumn ranges from about 75 for wet fields to 280 for fro2en turf (8). The intermediate values observed depend on soil type, moisture, condition, and other variables. 

Table 5. Abrasion Tests for Artificial Turf, Effective Pile Loss, %...

Artificial surfaces must be resistant to cigarette bums, vandaUsm, and other harm. Fire resistance is most critically evaluated by the NBS flooring radiant panel test (10). In this test, a gas-fired panel maintains a heat flux, impinging on the sample to be tested, between 1.1 W/cm at one end and 0.1 W/cm at the other. The result of the bum is reported as the flux needed to sustain flame propagation in the sample. Higher values denote greater resistance to burning results depend on material and surface constmction. Polypropylene turf materials are characterized by critical radiant flux indexes which are considerably lower than those for nylon and acryflc polymers (qv) (11). 

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