Dissolver disks

Another typical radial flow impeller is the disperser disk, also known as the toothed disk or dissolver disk. The EKATO MIZER disk belongs to this category, and consists... 

The ink is mixed vigorously until the carbon agglomerates are dispersed. Therefore, propeller stirrer or dissolver disks can be used. 

IR spectra can be recorded on a sample regardless of its physical state—solid liquid gas or dissolved m some solvent The spectrum m Eigure 13 31 was taken on the neat sample meaning the pure liquid A drop or two of hexane was placed between two sodium chloride disks through which the IR beam is passed Solids may be dis solved m a suitable solvent such as carbon tetrachloride or chloroform More commonly though a solid sample is mixed with potassium bromide and the mixture pressed into a thin wafer which is placed m the path of the IR beam... 

One important application of amperometry is in the construction of chemical sensors. One of the first amperometric sensors to be developed was for dissolved O2 in blood, which was developed in 1956 by L. C. Clark. The design of the amperometric sensor is shown in Figure 11.38 and is similar to potentiometric membrane electrodes. A gas-permeable membrane is stretched across the end of the sensor and is separated from the working and counter electrodes by a thin solution of KCl. The working electrode is a Pt disk cathode, and an Ag ring anode is the... 

CoUagenase specifically cataly2es the hydrolysis of coUagen, and is used in debridement of dermal ulcers and bums (191). It, like chymopapain, is also useful in the treatment of herniated lumbar disks (192,193). The rationale for coUagenase treatment in this instance is based on the preponderance of coUagen in herniated disk tissue, and the inabiUty of other en2ymes to dissolve coUagen (194). 

Buclizine may be taken without water. The patient is instructed to place the tablet in the mouth and allow it to dissolve or to chew or swallow the tablet whole. When given for motion sickness, one 50-mg dose is usually effective. For more extensive travel, a second 50-mg dose may be taken alter 4 to 6 hours. When administering scopolamine, one transdermal system is applied behind the ear approximately 4 hours before the antiemetic effect is needed. About 1 gof scopolamine will be administered every 24 hours for 3 days. If the disk detaches from the body, discard it and place a fresh one behind the opposite ear. (See Fhtient and Family Teaching Checklist Applying Transdermal Scopolamine.)... 

Filter IL of water sample through a filter paper. Place an Empore extraction disk in a Millipore extraction funnel. Rinse the disk with 10 mL of ethyl acetate, dichloromethane, and acetonitrile, successively. Dry the disk under vacuum and then rinse the disk with 10 mL of methanol and 20 mL of deionized water by vacuum filtration. Pass the prefiltered sample through the disk and elute alanycarb with two portions of 10 mL of acetonitrile. Transfer the eluates through anhydrous sodium sulfate into a 50-mL flask. Remove acetonitrile by rotary evaporation. Dissolve the residue in 1 mL of acetonitrile. 

Figure 7 Rotating disk to evaluate the intrinsic dissolution rate of compounds. The amount of drug dissolving per unit area is the same everywhere on the disk surface. This simplification makes the disk a powerful experimental tool in drug discovery and development. 

An alternative to the rotating disk method in a quiescent fluid is a stationary disk placed in a rotating fluid. This method, like the rotating disk, is based on fluid mechanics principles and has been studied using benzoic acid dissolving into water [30], Khoury et al. [31] applied the stationary disk method to the study of the mass transport of steroids into dilute polymer solutions. Since this method assumes that the rotating fluid near the disk obeys solid body rotation, the stirring device and the distance of the stirrer from the disk become important considerations when it is used. A similar device was developed by Braun and Parrott [32], who used stationary spherical tablets in a stirred liquid to study the effect of various parameters on the mass transport of benzoic acid. 

Germanium in samples dissolved in water or dioxane or dispersed into borax disks can be determined by XRF (X-ray fluorescence), using Ka radiation and arsenic as internal standard24. 

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