Deaning in place

Pipework systems, valves and vent filters should be properly designed to facilitate cleaning and sterilisation. The use of "dean in place" and "sterilise in place" systems should be encouraged. Valves on fermentation vessels should be completely steam sterilisable. Air vent filters should be hydrophobic and validated for their scheduled life span. 

Process related utilities such as purified water, water-for-injection, pharmaceutical compressed air (and/or other gases), clean or water-for-injection steam, and dean-in-place/steam-in-place systems shall be validated. 

Charles was one of those remarkable people who seem able to undertake a variety of tasks simultaneously with great energy, while appearing outwardly unruffled. In addition to his lecturing and other teaching, and research, Charles was admissions sub-dean in Chemistry over several difficult periods and for many years he organized annual combustion symposia in the Chemistry Department which attracted many people from all over the country and had a permanent place in the diaries of those working in the field. 

Donna J. Dean, National Institutes of Health A couple of weeks ago at an NIH-related activity focusing on underrepresented minorities in science and medicine I heard a very good phrase related to the glass ceiling concept the sticky floor. Even in places where there are no glass ceilings, there is still a sticky floor holding people back. 

For the production of the particular products referred to in paragraph 3.6 of the Guide to GMP, campaign working may be acceptable in place of dedicated and self-contained facilities. Because the toxicity of the materials may not be fully known, deaning is of particular importance account should be taken of the solubility of the product and of exdpients in various deaning solvents. 

During ail phases of clinical development, including the use of small-scale facilities or laboratories to manufacture clinical API batches, procedures should be in place to ensure that equipment is calibrated, dean, and suitable for its intended use. 

Hermetically sealed assemblies were not as compatible and, as expected, did not tolerate the pressure of the deaning process. A motor stater, composed of wire windings potted in place with an unfilled epoxy was also found to be incompatible with the cleaning process. In this case, the carbon dioxide would fill voids in the epoxy and then during depressurization cause fracturing at these voids. Later this problem was alleviated by deaning at a lower pressure and decreasing the decompression rate. 

Slug/semi-annular flow Here both slug and semi-aimular flows are present. The bubble velocity increases with heat flux and the rear of the elongated bubbles begin to break up (Figure 3.2d). Coalescence is no longer dean but instead creates a chum-like zone in place of the liquid slug. 

It was shown by Dean that, where the level of fluoride in the water was about 1 mg per litre (1 ppm), the incidence of mottled enamel was slight while the incidence of caries was 50% lower than in places where the water contained 0-2 mg of fluoride per litre or less. Where the level of fluoride was 2 mg per litre there was a slight further decrease in the incidence of caries but an increase in the degree of mottling. As a result of this and many other studies, it was concluded that the optimal level of fluoride in the water supply in temperate climates is about 1 mg per litre. From 1945 onwards, studies on the effects of raising the fluoride level of the communal water supply to approximately 1 mg per litre were made in various parts of the world. 

Related at least in principle to ductless hoods are laminar flow hoods, sometimes called dean hoods. These are devices intended to protect the work being performed from particulates in the air, which is accomplished by bathing the work area with HEPA filtered air either blown at low velocity over the work area or blown from the bottom of the hood as an air curtain. Only approximately 10 % of the air flow is through the face of the hood. These are intended to protect the work or samples inside the hood, not primarily the user. These units should not be used in place of chemical fume hoods, rather they are used to protect the work from dust or pollen. 

Place a mixture of 53 g. of A.R. lactic acid (85-88 per cent, acid), 75 g. (85-5 ml.) of commercial anhydrous isopropyl alcohol, 300 ml. of benzene and 20 g. of Zeo-Karb 225/H (1) in a 700 ml. bolt-head flask, equipped with an automatic water separator (e.g., a large modified Dean and Stark apparatus with a stopcock at the lower end, see Fig. Ill, 126, 1) carrying an efficient reflux condenser at its upper end, and a mercury-sealed stirrer (alternatively, the hquid-sealed stirrer shown in Fig. 11,7,11, c. may be used). Reflux the mixture, with stirring, on a steam bath for 5 hours or until water no longer collects in appreciable amount in the water separator run off the water from time to time. Filter off the resin at the pump and wash it with two 25 ml. portions of benzene. Shake the combined filtrate and washings with about 5 g. of precipit-ated calcium... 

In a 3-I. three-necked, round-bottomed flask fitted with a mechanical stirrer, reflux condenser, and separatory funnel is placed 400 cc. of absolute alcohol (Note i). Through the condenser tube is added slowly, 23 g. (i gram atom) of dean sodium cut into thin slices. The completion of the reaction is hastened by heating the flask on a steam bath. When the sodium has dissolved completely, 143 g. (i.i moles) of ethyl acetoacetate is introduced slowly. Alter starting the mechanical stirrer, 123 g. (i mole) of ethyl chloroacetate (Note 2) is added slowly over a period of an hour, and the reaction mixture is refluxed for five to six hours. At this point the reaction mixture should no longer give an alkaline reaction with moist litmus. 

A mixture of 105.6 g. (1.1 moles) of freshly distilled furfural, 87.0 g. (1.0 mole) of 98% cyanoacetic acid (Note 1), 3.0 g. of ammonium acetate, 200 ml. of toluene, and 110 ml. of pyridine is placed in a 1-1. round-bottomed flask equipped with a Stark and Dean water trap and reflux condenser. The mixture is boiled under reflux for 2 days. The theoretical quantity of water is collected in the trap within 1 hour. Upon completion of the reflux period, the solvent is removed under reduced pressure by heating on a water bath. The residue, distilled through a 15-cm. Vigreux column at 11 mm. pressure, yields 88.6-93.3 g. (74.5-78%) of colorless liquid boiling at 95-97°, 1.5823-1.5825. 

If a bottle is placed in the bench, a wake is easily created in the legitni with horizontal flow. This is depicted visually with smoke in Fig. 10.58. If the bottle is situated close to the opening of the unit, ambient air will be entrained intt> the dean zone in the bench. The length of the reversed region can be < sti mated to two to three times the diameter of the bottle, and can reach twice this length w hen the bottle is situated just beside the side wall. 

In a 1-L rbf attached to a Dean-Stark trap, equipped with a reflux condenser is placed distilled aniline (1, 46.5 g, 45.5 mL, 0.5 mol), commercially available ethyl acetoacetate (5, 65 g, 63.5 mL, 0.5 mol), benzene (100 mL) and glacial AcOH (1 mL). The flask is heated at about 125 °C, and the water which distills out of the mixture with the refluxing benzene is removed at intervals. Refluxing is continued until no more water separates (9 mL collects in about 3 hrs) and then for an additional 30 min. The benzene is then distilled under reduced pressure, and the residue is transferred to a 125 mL modified Claisen flask with an insulated column. The flask is heated in an oil or metal bath maintained at a temperature not higher than 120 °C while the forerun of 1 and 5 is removed and at 140-160 °C the product distills giving 78-82 g, 76-80% yield of 6. 

Toluene (99.8% anhydrous, water <0.001%, evaporation residue <0.005%) was purchased from Aldrich Chemical Company and used as received. The capacity of the receiver in the Dean-Stark trap was 28 mL. The initial amount of toluene placed in the flask was 88 mL. Upon heating to reflux, 28 mL of toluene was distilled from the flask and collected in the receiver. The remaining volume of toluene in the reaction flask was ca. 60 mL, corresponding to an approximately 0.50M concentration of the reactants. 

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