Drinking tubes

All baboons had served in studies of intravenous self-injection with a variety of drugs. They had continuous access to water via a drinking tube and to food pellets (as described below) and received two pieces of fresh fruit and a multivitamin daily. 

The second new concept was a drinking tube. The drinking capability allowed a soldier to drink from his canteen in a contaminated battlefield without unmasking. This was considered critical because of the longer times required to wear protective gear around persistent nerve agents and the possible use of the mask in desert and tropical climates.30... 

Fig. 16-4. The M41 Protection Assessment Test System (PATS). Ambient air is assessed through the green hose. Air inside the mask is assessed through the colorless hose, which couples with the protective mask by means of the drinking tube extension. For further information, see Department of the Army. Protection Assessment Test System (PATS). Washington, DC DA 14 January 1995. Training Circular 3 41.

This mask can be used in any climatic condition, but the M4 winterization kit must be installed when used in temperatures of -20°F or below. A voice-mitter outlet valve, provided on the front of the facepiece, transmits the user s voice outside the mask. A drinking tube assembly is attached just below the voicemitter and allows the user to drink while wearing the protective mask. The drink system couples with the Ml canteen cap (Figure 16-6). 

Communication is provided by two voicemitters. One is mounted in the front to allow face-to-face communication the second is located in the cheek to permit the use of a radio telephone handset. A drinking system consists of internal and external drink tubes the external tube has a quick-disconnect coupling that connects with the Ml canteen cap. A six-point, adjustable harness with elastic straps located at the forehead, temples, and cheeks comes together at a rectangular head pad. 

Filtration is provided by one C2A1 canister mounted on either side of the facepiece. The primary voicemitter is located over the mouth area with a secondary voicemitter in the cheek area to utilize telephone handsets. The mask incorporates a drinking tube, which connects to the Ml canteen cap. The mask has a six-point, adjustable head harness suspension made of elastic, which comes together in the center head back into a rectangular patch of woven material. The mask comes in three sizes small, medium, and large. Accessories include a carrier bag, a butyl-coated nylon cloth hood, outserts to protect the lens in storage, and a waterproof bag. 

Second, the presence of extraneous taste cues is easier to control when stimuli are presented in a fluid vehicle. For the evaluation of odors, feeding tests are often superior to drinking tests. This is because volatile stimuli are more easily expressed in the typical feeding context (e.g., a covered dish) than in a drinking context (e.g., stimulus presentation in a drinking tube with a small opening). 

Figure 7.2. Materials to construct a calibrated drinking tube created from a sipper tube attached to a syringe with Tygon tubing.

Thermoforming and Extrusion. Improved equipment and polymers have increased the capabiUty to extmde and thermoform polypropylene however, consumption of polypropylene in these areas has not grown dramatically. Drinking straws are commonly extmded from polypropylene, however most larger diameter tubes, such as pipes and conduits, are predominantly extmded from other thermoplastics. Extmded sheet is thermoformed into food containers and trays polypropylene is used when microwavabiUty is desired. 

Soft-drink bottles made from poly(ethylene terephthalate) (PET) are usuady made by stretch-blow mol ding in a two-step process. Eirst, a test-tube-shaped preform is molded, which is then reheated to just above its glass-transition temperature, stretched, and blown. Stretching the PET produces biaxial orientation, which improves transparency, strength, and toughness of the botde (54,56). A one-step process is used for many custom containers that are injection stretch-blow molded. 

Alpha counting is done with an internal proportional counter or a scintiUation counter. Beta counting is carried out with an internal or external proportional gas-flow chamber or an end-window Geiger-MueUer tube. The operating principles and descriptions of various counting instmments are available, as are techniques for determining various radioelements in aqueous solution (20,44). A laboratory manual of radiochemical procedures has been compiled for analysis of specific radionucHdes in drinking water (45). Detector efficiency should be deterrnined with commercially available sources of known activity. 

Initially a molten tube of plastic called the Parison is extruded through an annular die. A mould then closes round the parison and a jet of gas inflates it to take up the shape of the mould. This is illustrated in Fig. 4.21(a). Although this process is principally used for the production of bottles (for washing-up liquid, disinfectant, soft drinks, etc.) it is not restricted to small hollow articles. Domestic cold water storage tanks, large storage drums and 2(X)... 

The simplest model ignores tortuosity and assumes the bed equivalent hydro-dynamieally to a matrix of straight tubes - like a bundle of drinking straws e.g. as in Figure 2.10. 

Benzene (80 ml) is placed in a suitable pressure vessel (soft drink bottle or hydrogenation bottle) and chilled to 5°. The bottle is weighed, and a gas dispersion tube connected to a cylinder of butadiene is immersed in the benzene. Butadiene is introduced into the flask with continued cooling until a total of 32 g has been transferred. Pulverized maleic anhydride (50 g) is added to the bottle, which is then capped or stoppered with a stopper wired in place. The bottle is allowed to stand at room temperature for 12 hours, then is heated (behind a safety shield) to 100° for 5 hours. The bottle is cooled, then opened, and the contents are transferred to an Erlenmeyer flask. The mixture is heated to boiling, and petroleum ether is added until there is a slight turbidity. After cooling, the product is collected, mp 101-103° (yield 90%). 

Truck-fender liners, drinking cups, juice and dairy-product containers and lids, test-tube racks... 

During the 1960s, Americans lived in a lead-drenched society. They fueled their cars with leaded, antiknock gasoline. They ate food and their babies drank milk from lead-soldered cans. They stored drinking water in lead-lined tanks and transported it through lead or lead-soldered pipes. They squeezed toothpaste from lead-lined tubes and poured wine from bottles sealed with lead-covered corks. They picked fruit sprayed with lead arsenate pesticide and served it on lead-glazed dishes in houses painted and puttied with lead-based compounds. 

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