Handling, clean surfaces

The slurry seal with the evacuation line is designed to handle/evacuate suspended solids, crystals, sediment, and dirt in the pumpage. The seal s springs are located out of the fluid. The o-rings move and rub across a clean surface as the faces wear. The o-rings are placed away from the heat generated by the faces. 

NOTE Cuvettes must be kept scrupulously clean avoid handling the surfaces of the cell (see Critical Parameters). 

G. Nickel. Nickel (nip 1,453°C), finds its primary use in the construction of apparatus to handle fluorine and volatile fluorides. In this situation the metal is rendered passive by a fluorine coating. Nickel plating is easily performed and provides a means of imparting corrosion resistance. The metal may be machined, silver soldered, copper brazed, or welded. However, the weld should be performed on clean surfaces because the presence of impurities containing lead, sulfur, phosphorus, and various low-melting metals leads to embrittlement and failure at the weld. 

Transparent Vitreosil apparatus must be given special care, as cleanliness is most important. At the working temperature many materials combine with silica and cause stains or devitrification. In addition to normal cleaning the surfaces are wiped with cotton wool dipped in alcohol. The cleaned surfaces must not be handled as finger marks are sufficient to cause devitrification. 

Lithium can be weighed and handled without any danger. It is usually delivered in cylindrical sticks of 1 to 1.5 cm in diameter. After complete removal of the protective liquid with a tissue, the required amount of metal is cut off and subsequently flattened with a hammer on a clean surface (e.g. iron block) to a thickness of a few mm. Using scissors, the flattened piece is then cut into chips. If a... 

Inspections may be numerous, making speed and ease of handling very important. Inspection profits from the visually clean surface provided by vapor degreasing without extensive rinsing or drying. 

Because of low temperature stability and potential resin degradation, quats are not normally used as internal antistats. However, when topically applied, quats can achieve low surface resistivities and are widely used in such short-term applications as the prevention of dust accumulation on plastic display parts. More durable applications are not generally feasible because of the ease with which the quat antistat coating can be removed from the plastic during handling, cleaning, or other processes. For longer-term protection internal antistats are used. 

The process of adsorbate deposition should be carried out in a well-controlled environment. UHV is ideal in storing the surfaces and is indispensable for handling clean Si surfaces of Si. UHV chambers and tubings are convenient for most heating and gas exposure treatments. H Si(lll) and organic-modified Si surfaces are... 

AH solvents which are efficient for cleaning surfaces will also remove the natural body greases from the hands. Whilst direct handling and wiping of components with solvent soaked cloths is to be deprecated, there are occasions when it will be done. Because barrier creams will themselves contaminate the surfaces to be cleaned, the hands are best protected with cheap disposable polyethylene gloves. 

Often the best way to handle surfaces is to mount them in fixtures so that the active surfaces are not contacted directly. The next best technique is to use mechanical tools to hold and handle the surfaces. Often, fixtures and tools can be designed that prevent surfaces from being touched in critical areas, giving abrasive transfer between surfaces. Abrasive transfer can be a problem even with metal tools. For example, a clean oxide surface will easily transfer chromium from chromium-plated tools to the clean surface if there is abrasion. A protocol has to be established as to when and how to clean, store, and use the tools, and what to do with them when they become contaminated. 

Cleaned surfaces should be stored in a non-recontaminating environment. Often, surfaces to be stored are held in clean fixtures to reduce the necessity for handling the surfaces directly. The fixtures must be compatible with the storage environment"... 

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