Combined cleaning methods

You may combine both methods by handwriting basic information, and using a computer for answers that run more than a few words. Be sure the font size you are using will fit into the spaces on the application. Then, print out your answers, and literally cut and paste them neatly to the application. Alternately, if the school accepts copied applications, type and cut and paste everything, then make a clean copy to submit. 

Equipment — On introduction of each new piece of equipment or process, the cleaning method should be validated, using one or an appropriate combination of the following methods ... 

The existing cleaning methods can be divided into wet and dry cleaning. The wet cleaning process uses a combination of solvents, acids, surfactants and deionized (DI) water to spray and dissolve contaminants from the surface area. The Dl water is used to rinse after each chemical use. The oxidation of the wafer surface is sometimes integrated into the cleaning... 

Supercritical fluids have long been known for their abilities to dissolve organic contaminants. Their ability to display a wide range of solvent characteristics and the ability to tune solubility with small changes in temperature and pressure were identified early on in our search for alternative cleaning methods. The gas-like diffusivity and low surfece tension combined with liquid-like densities were important... 

When the decomposition is carried out in an inert solvent, methyl acetate and ethane are formed, whereas in the gas-phase decomposition methyl acetate is completely absent and ethane is produced in much smaller quantity.85 It was suggested that the dimers in solution represent the recombination of methyl, and the combination of methyl and acetoxy radicals, within the solvent cage. 85 87 The decomposition of diacyl peroxides provides a fairly clean method for the production of alkyl radicals and, therefore, it has been used in most quantitative and preparative studies of the alkylation of heterocyclic compounds. 

Validation of cleaning methods should reflect actual equipment use patterns. If various APIs or intermediates are manufactured in the same equipment and the equipment is deaned by the same process, a worst-case API or intermediate can be selected for purposes of cleaning validation. The worst-case selection should be based on a combination of potency, toxicity, solubility, stability, and difficulty of deaning. 

The snow gun cleaning method uses solid CO2 ice crystals as a jet medium. With its combination of mechanical (ablation), thermal (freezing), and chemical (dissolution) properties, CO2 snow is able to gently detach and remove a whole variety... 

Physical cleaning can remove only matter that is physically distinct from the coal, such as small dirt particles, rocks, and pyrite. Physical cleaning methods cannot remove sulfur that is chemically combined with the coal (organic sulfur), nor can they remove nitrogen from the coal. Currently, physical cleaning can remove 30%-50% of the pyritic sulfur and about 60% of the ash-forming minerals in coal. 

A wet scrubber can also be combined with other flue gas-cleaning methods. Gases can be first cleaned by a washer, then treated by a thermal reactor, and then treated again by a wet scrubber. 

Cleaning Method 3 Combination of water-jetting and use of abrasive balls for cleaning E1007-A. 

No one method, however, has all the desired features of simplicity, low cost, and effectiveness. To achieve optimum cleanliness of substrate surfaces, combinations of the various cleaning methods must be used. There is no universal approach to cleaning cycles. There are, however, some general guidelines to follow when establishing cleaning sequences. 

The following cleaning methods can be used alone or in combination ... 

This cleaning method is commonly used in metal industries. The process consists of cleaning parts in a mixture of surfactant, sodium or potassium hydroxide, and combinations with sodium carbonate, sodium silicate, borates and in special cases sodium gluconate. 

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