Metal containers closures

On completion of the reaction, the material (if not immediately used) must be stored in a clean, dry container. The material of construction must be able to withstand the heat of the material plus any further reheating required. If metal containers are used, they must be lined with an epoxy or similar material that is nonreactive to the polyurethane prepolymer. Any remaining air in the container must be replaced with dry nitrogen gas. All mating surfaces of the closure must be free of the polyurethane prepolymer. 

The primary inhibitory effect of cadmium on photosynthesis of excised leaves was proposed to be metal-induced stomatal closure (Bazzaz et al., 1974 Lamoreaux and Chaney, 1978). In epidermal peels floating on a metal-containing solution, stomatal closure was reported (Bazzaz et al., 1974). Inhibition of transpiration by several metals, especially by cadmium, is well documented (Poschenrieder et al., 1989), but is not necessarily at the stomatal level. Metal-induced stomatal closure can indirectly be responsible for a decrease of photosynthetic C02 fixation indeed. However, several enzymes of the Calvin cycle are directly affected by metals. 

Goods Packaging Metal Food Containers Plastic Containers Metal Plastic Closures... 

Container closure systems required for implantable devices are further restricted by the fact that they are required to be compatible with the formulation over the intended shelf life and therapeutic application time as well as being biocompatible. This means that the system not only must afford protection to and contain the formulation but also cannot cause any potential adverse effects, such as allergy. Typically, implantable systems are composed of biocompatible metals, such as titanium or polymers such as polyethylene glycol or polylactic-co-glycolic acid. 

The most common glass-packed solid oral dosage forms are oral powders and granules for reconstitution. A typical solid oral dosage form container closure system is a glass bottle (although plastic bottles are also used) with a screw-on or snap-off closure. A typical closure consists of a metal cap, often with a liner and frequently with an inner seal. 

In common with glass and plastic containers, the performance of a metal container is partly governed by the nature of the closure involved. Some of these closures are similar to those used on glass and plastic containers, e.g. plastic and metal screw closures and frictional closures such as plug or slip lids. Others, which are mainly used on metal (or metal composite) containers, are lever lids and permanent mechanically seamed-on closures. 

Table 11.2 applies to conventional continuous threaded preformed screw closures as applied to glass, plastic or metal containers, but is also relevant to multistart and lug type finishes. Certain features on the container have to be matched against the closure. 

The General Tests and Assays. This section of the USP gives methods for tests that are general in nature and apply to a number of the substances. Procedures are iacluded for such tests as heavy metals, melting point, chloride, sulfate, sterility, bacterial endotoxins, and pyrogens. Also iacluded are descriptions of various analytical techniques, such as spectrophotometry, chromatography, and nmr, and descriptions of tests to be used on glass or plastic containers, mbber closures, etc. 

Cans with replaceable closures for such products as dry foodstuffs, pharmaceuticals, tobacco, solvents, liquid fuels and paint. These usually contain an appreciable amount of oxygen. Tinplate closures for bottles and jars made of non-metallic materials may also be considered in this category. 

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