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Process procedure modifications

For projects needing stringent QC, control charts are recommended to monitor analyte recoveries throughout an investigation (see Taylor, 1987, for a detailed discussion). Briefly, during each quarter of a project, the last 20 observations of recoveries from QC spikes are used to generate a control chart. Control limits are established for the analytical process as described by Taylor (1987). When control limits are exceeded, sample analyses are suspended until the problem step(s) can be identified and corrected. These actions must follow an appropriate protocol for corrective action. The results of this type of investigation or procedure modification become a part of the permanent record of the sample set and the project. [Pg.104]

Because of the importance of soy sauce as a food flavorant, a new method for its production was developed. The importance of this novel processing procedure is that it significantly shortens the fermentation processing time by half or to about three months. Attempts at further modification of the process to prepare low-sodium-chloride-containing soy sauce are also described. [Pg.200]

Nonconformances may fall into the category of manpower, machinery methods, materials, etc. Employees not following procedures or unable to execute required steps of the process indicate a poorly designed process requiring modification and/or improved training. Machinery failures often indicate poor qualification, validation, calibration, or maintenance programs. Unexpected results or outcomes are indicative of poor process design, characterization, or a break down between processes. [Pg.270]

Spike the matrix substitute with a realistic, expected amount of test compound and repeat the process of step 4. If there are significant losses evident in step 4 and these have not been eliminated, then a procedure modification is already indicated since a higher overall concentration factor will be required to reach the predetermined limit of sensitivity or lower limit of acceptable concentration of the test compound. At any rate, it will be necessary to establish that the realistic quantity of test compound is handled by the workup procedure in ess-... [Pg.411]

Modification of silica gel with volatile or gaseous compounds is performed in the vapour phase. Industrial-scale reactors and laboratory scale gas adsorption apparatus have been used. In the industrial field, fluidized bed and fluid mill reactors are of main importance. In fluidized bed reactors,82 the particles undergo constant agitation due to a turbulent gas stream. Therefore, temperatures are uniform and easy to control. Reagents are introduced in the system as gases. Mass transport in the gas phase is much faster than in solution. Furthermore, gaseous phase separations require fewer procedural steps than solution phase procedures, and may also be more cost-effective, due to independence from the use and disposal of non-aqueous solvents. All these advantages make the fluidized bed reactors preferential for controlled-process industrial modifications. [Pg.185]

The condensation reaction required significant process development modifications from the procedure used to produce the initial drug development requirements. 2-Chloronicoti-noylchloride (5) was prepared in situ during medicinal and chemical development runs by adding 2-chloronicotinic acid to a 5 molar excess of thionyl chloride as a neat reaction mixture. Upon completion of the reaction, excess thionyl chloride was removed by distillation. The residue was then redissolved in toluene, followed by the addition of CAPIC in toluene and sodium carbonate to neutralize the excess HCl liberated from the condensation. An alternative procedure was developed with the use of a 10% molar excess of thionyl chloride in toluene to produce (5). The excess thionyl chloride was removed by distillation and to the... [Pg.425]

Hamm, W. (2001) Regional differences in edible oil processing procedures. 1. Seed crushing and extraction, oil movements, and degumming. 2. Refining, oil modification, and formulation. Lipid Tech., 13, 81-84 and 105-109. [Pg.17]

In order to illustrate the application of the standard addition method and of the subsequent data processing procedure, let consider the mixture of salicylic acid, caffeine and acetaminophen, discussed in a previous example. The aim is to determine the concentrations of the three chemical components. Table 2 includes the modifications of the component concentrations (5 modifications are performed) and the absorbances both for the original solution (where concentrations have not been modified) and for the five solutions in which the three chemical components have been modified. All absorbance values are read at the same set of 18 wavelengths (A = 18). [Pg.313]

Better Process Control modification of the working procedures, machine instructions, and process record keeping for operating the processes at higher efficiency and lower rates of waste and emission generation... [Pg.205]

Since plants and processes undergo modifications during their lifetime, a procedure for dealing with modifications has to be established. The modifications and the accompanying safety analyses have to be documented ( management of change ). [Pg.101]

Modification procedures for carbon electrodes are quite diverse. For convenience, in this chapter, they are broadly divided into two parts covalent and non-covalent modifications. It is worth mentioning that this chapter is not intended to cover the entire hterature on carbon modification, instead the focus is given on basic features of each process of modification and how it changes the nature of carbon electrode surfaces. From the wide variety of applications of modified electrodes, a few selected articles are discussed in short at the end of each modification process to demonstrate its utility. [Pg.212]

The improvements obtained in mechanical properties result from improved interaction between the two polymers. As pointed out by Datta and Lohse [41], the changes in mechanical properties may not always be taken as an evidence for compatibilization. There is a complex correlation between the morphology and the physical properties of a blend, which is not completely understood. In the present case, the complications were minimized by using a standard processing procedure for all samples, and by keeping the amount of modifications at a minimum. [Pg.185]

Is there a process to ensure that modifications to processes, procedures, systems, and organization are communicated to all relevant staff ... [Pg.120]

Structures greatly by modifications in primary processing procedures and beat treatment, similar to Ti-6A1-4V. By stoitable selection of working and annealing temperatures with respect to the P transus temperature, microstructures can be developed hav-... [Pg.178]

Until recently, there were only few ways to introduce specific modifications into the reaction center structure which were suited for a parametric study of charge separation processes. Selective modifications were limited to the two quinones, and Qg (Warncke Dutton), the presence and nature of the divalent metal ion located between and Qg [3], and the removal of the H-protein subunit [4]. The only possibility to interfere with one of the four bacteriochlorophylls, the one at the site Bg in reaction centers of Rhodobacler (Rb.) sphaeroides, consisted in the borohydride treatment [5] and the chemistry of this procedure is still under debate 16]. [Pg.453]

Change control procedures to process all modifications and track them through the design and testing phases... [Pg.253]


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See also in sourсe #XX -- [ Pg.50 ]

See also in sourсe #XX -- [ Pg.50 ]




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