Dispense Quantity

The reason for this is when an adhesive is dispensed at high pressure, there is a pressure surge as the valve opens causing excess adhesive to flow. This quickly disappears as the flow rate steadies but at the end of the bead as the valve closes some adhesive can be pushed forward. 

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The type of application and workplace conditions, such as production rate, dispense quantity and cure speed will determine whether manual, semi-automatic or fully automatic dispensers will be required. 

In these cases a small internal chamfer can help to improve the integrity and aesthetics of the joint and it allows for some tolerance on the dispensed quantity of adhesive (Figure 5.21) as it can be qnite difficnlt to dispense the exact quantity of adhesive so that it stops exactly at the edge of the joint. The chamfer creates a small gap to allow for the adhesive flow. 

Figure 10.2 shows a typical pressure-time output as the valve operates. There is a brief surge in pressure as the valve opens and then this levels out fairly quickly until the end of the elapsed dispense time. If there is a bubble in the adhesive or a blocked nozzle the pressure-time curve will be changed (Figure 10.3) and by integrating the area under the curve, the software controller [1] can quickly determine whether the dispensed quantity was within preset tolerances. 

For the filtration of small quantities of dilute solution, it is often possible to dispense with the outer heater, and use the ordinary glass funnel which has been heated above a flame immediately before use. 

Provision of a defined quantity for dispensing and metering, as in agricultural chemical granules or pharmaceutical tablets. 

Because of the small amount of lubricant dispensed, the divider block system must be employed with the mini-lube method of lubrication previously discussed. The special divider block is usually connected to oiii plunger on a multiplunger pump, taking advantage of the smaller output to do the initial flow reduction. The balance of the pump s plungers may be used where a more conventional quantity of lubricant can be used. 

For MPN determination, sterile pipettes calibrated in 0.1-ml increments are used. Other equipment includes sterile screw-top dilution bottles containing 99 ml of water and a rack containing six sets of five lactose broth fermentation tubes. A sterile pipette is used to transfer 1.0-ml portions of the sample into each of five fermentation tubes. This is followed by dispensing 0.1 ml into a second set of five. For the next higher dilution (the third), only 0.01 ml of sample water is required. This small quantity is very difficult to pipette accurately, so 1.0 ml of sample is placed in a dilution bottle containing 99 ml of sterile water and mixed. The 1.0-ml portions containing 0.01 ml of the surface water sample are then pipetted into the third set of five tubes. The fourth set receives 0.1 ml from this same dilution bottle. The process is then carried one more step by transferring 1.0 ml from the first dilution bottle into 99 ml of water in the second for another hundredfold dilution. Portions from this dilution bottle are pipetted into the fifth and sixth tube sets. After incubation (48 h at 35 C), the tubes are examined for gas production and the number of positive reactions for each of the serial dilutions is recorded. 

To obtain the calibration standards, take aliquots ranging from 50 /xL to 300 juL As, from the working standard solution, using an Eppendorf micropipette. Add the appropriate microlitre quantities to the reaction vessel of the vapour generation system, together with 10 mL of hydrochloric acid (AM), delivered from a calibrated dispenser. 

Under federal law, limited quantities of certain schedule V drugs may be purchased without a prescription directly from a pharmacist if allowed under state law. The purchaser must be at least 18 years of age and must furnish identification. All such transactions must be recorded by the dispensing pharmacist. 

Several guidelines are available in the literature for the pharmacist who must extemporaneously prepare an ophthalmic solution. The USP contains a section on ophthalmic solutions, as do other compendia and several standard textbooks. Since the pharmacist does not have the facilities to test the product, he or she should dispense only small quantities, with an expiration date of no more than 30 days. Refrigeration of the product should also be required as a precautionary measure. To reduce the largest potential source of microbial contamination, only sterile purified water should be used in compounding ophthalmic solutions. Sterile water for injection, USP, from unopened IV bottles or vials is the highest-quality water available to the pharmacist. Prepackaged sterile water with bacteriostatic agents should not be used. 

Constraints (4.18) states that the inlet stream into any operation j is made up of recycle/reuse stream, fresh water stream and a stream from reusable water storage. On the other hand, the outlet stream from operation j can be dispensed with as effluent, reused in other processes, recycled to the same operation and/or sent to reusable water storage as shown in constraints (4.19). The inlet concentration into operation j is the ratio of the contaminant amount in the inlet stream and the quantity of the inlet stream as stated in constraints (4.20). The amount of contaminant in the inlet stream to operation j consists of the contaminant in the recycle/reuse stream and the contaminant in the reusable water storage stream. The following storage specific constraints are also imperative for the completeness of the model for scenario 3. 

Bj2 are prepared from a triturate of vitamin Bi2 and mannitol (Nutritional Biochemicals Co., Cleveland, Ohio). Double-strength basal medium (twice the value listed in the tables) is prepared and dispensed in 2.5-ml quantities into 10-ml micro-Fembach flasks (Kimble Glass... 

The successful performance of dispensing and compounding operations in a pharmacy depends on a thorough understanding of the principles of the prescription balance and strict adherence to the procedures of its care and use. Therefore, it is essential to learn proper weighing techniques, and to be conscious of the limitations of the balance to weigh certain quantities. All pharmacies are required to have a Class A prescription balance which meets the requirements of the National Bureau of Standards. It is based upon the principle of torsion. Some states may allow the use of a balance other than the Class A prescription balance, provided that their sensitivity requirement is six milligrams or less. 

Certain oral medications may be prepared in bulk to be dispensed later or to be used as stock solutions. Official formulas for manufacturing, in general, are based on the preparation of one liter or one kilogram of product. The quantities of active ingredients required to prepare in bulk can be determined by the method of proportions which is outlined in Chapter 1. 

A physician prescribes tetracycline suspension for a patient to be taken in doses of two teaspoonfuls four times a day for four days, and then one teaspoonful four times a day for two days. How many milliliters of the suspension should be dispensed to provide the quantity for the prescribed dosage regimen ... 

A 10 mCi dose is ordered and the radiopharmaceutical activity concentration is presently 16 mCi/mL. What is the quantity to be dispensed to provide the necessary radioactivity ... 

Weigh out 2100 mg of sulfasalazine powder, 28 mg of prednisone (use aliquot method for weighing this quantity), and add sufficient lactose to obtain a total of 2730 mg of the powder. Fill 195 mg in each of the 14 capsules that are required to be dispensed. 

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