Recovery tests

A second wtinMe-recovery test, AATCC test method no. 128, describes the determination of the appearance of textile fabrics after intentional wrinkling followed by evaluation of appearance in comparison to standard repHcas. A visual rating from 1 (wrinkled) to 5 (smooth) is assigned. This method may be used for both woven and knitted fabrics, whereas the recovery angle method is appHcable only to woven fabrics. 

The MDCs are estimated from an S/N of the diphenyl ether peaks of at least of 3 in the recovery test. With fortification levels between 0.2 and 0.5mgkg recoveries of bifenox from brown rice matrices ranged from 85 to 102% with the limit of detection (LOD) and limit of quantitation (LOQ) being 0.010 mg kg according to the analytical method of the Notification of the Ministry of the Environment, Japan. By the residue analysis method described in Section 2.2.2(3), recoveries of chlornitrofen and CNP-NH2 from brown rice and vegetables with fortification levels of 0.04-0.10 mg kg ranged from 82 to 98%. The LOD for each sample was 0.005 mg kg for chlornitrofen and CNP-NH2. ... 

Method validation is needed to demonstrate the acceptability of the analytical method. A recovery test on a chemical being determined should be performed in order to verify the reliability of the series of analyses. Recovery studies are usually conducted by spiking untreated sediment with the target chemical at the deteetion limit, quantitation limit and in the range of 10-50 times the detection limit. The method is considered acceptable when the recoveries typically are greater than 70%. When the recovery is less than 70%, an improvement in the analytical methods is needed. Where this is not possible for technical reasons, then lower recovery levels may be acceptable provided that method validation has demonstrated that reproducible recoveries are obtained at a lower level of recovery. Analysis is usually done in duplicate or more, and the coefficient of variation (CV) should be less than 10% to ensure that recoveries will be consistently within the range 70-110%. 

In a recovery test after all the load is removed at time / the creep is all recoverable except for the flow that occurred in the dashpot with viscosity %-... 

Recovery tests or use of internal standards for pre-treatment and use of reference materials for analytical calibration and traceability [5]. 

Here the concept of statistical control is not applicable. It is assumed, however, that the materials in the run are of a single type. Carry out duplicate analysis on all of the test materials. Carry out spiking or recovery tests or use a formulated control material, with an appropriate number of insertions (see above), and with different concentrations of analyte if appropriate. Carry out blank determinations. As no control limits are available, compare the bias and precision with fitness-for-purpose limits or other established criteria. 

Referee Laboratories and Spike Recovery Testing. Outside laboratories, with demonstrated performance records, can be used to evaluate the suitability of a candidate method when none of the other accuracy testing options is feasible. However, This technique provides a very weak form of accuracy assessment. Indeed, it provides a comparability check, not an accuracy measure. Similarly, spike recovery tests provide only weak evidence of method accuracy. Quantitative spike recovery only indicates that the added form of the analyte was recovered. If the added form responds differently toward sample preparation or detection the utility of spike recovery testing remains doubtful. 

Method and Laboratory Bias Uuiag From Recovery Tests... 

Recovery tests, for example the recovery of a standard addition to a sample in the validation process, can be used to estimate the systematic error. In this way, validation data can provide a valuable input to the estimation ofthe uncertainty. 

Estimation of the bias (from analyses of CRM, PT results or recovery tests)... 

M) Parachute Recovery Test. This test developed at PicArsn has been used for the recovery of fired mechanical time fuzes for investigation. The method consists... 

Y) Vertical Recovery Test. The purpose of this test is to det causes of malfunctioning of artillery fuzes when the projectiles are fired at very high angles of elevation, such as 83 to 90° and are landed on their bases on soft ground. A fuze passes the test if it is landed without damage so that it can be examined. A detailed description of the test is given in the Journal of the JANAF (Joint Army-Navy-Air Force) Fuze Committee, Serial No 41 (July 1966) (p IIIB-14 of Ref 39)... 

Trace metals may be lost by adsorption on precipitates, such as the silica formed on digestion using oxidizing acids. This possibility should be investigated (e g. by recovery tests). 

The validated HPLC test method will be used for the determination of chemical residues. The validation of test method will be performed by addition and recovery tests. 

TABLE 2. Recovery Test and Extrusion Testing Results for Selected... 

Hot rolling particles from the recovery test on the cuttings were used. Samples were extruded in a CT 15 compressometer device at a rate of 40 mm /min where the pressure necessary to extrude the particles was recorded. The harder the particles, the higher the pressure, the better the protection with regard to penetration of water, and the better the inhibiting effect on clay swelling. Testing results are provided in Table 2. 

Accuracy. In the quantitative method that is used to measure the heavy metal quantity in the drug substance, the accuracy is usually represented by the recovery rate obtained from a spiked recovery test where lead is added to the samples. Since the heavy metals limit test specified in monograph specifications is a test where the intensity of coloring of the samples with sodium sulfide is compared with that of the control solution, it is necessary to confirm that heavy metal components can be detected fully in the process of test solution preparation. The Heavy Metals Limit Test in JP specifies four preparation methods for the test solutions. An appropriate method will be selected and used for further testing. The test method that gives the best recovery rate is to be adopted. The procedure is as follows ... 

The spiked recovery test cannot produce a favorable result. The following precautions should be taken at the time of preparation of the test and control solutions from samples. 

The extensiveness of the reported recovery tests varies from studies of a large number of components and conditions (7, 17, 18, 25, 36, 60,... 

Note The references to the more extensive recovery tests are underlined in each category. Usually these tests involve more than 10 compounds at least three chemical classes and at least two conditions such as flow rate, pH, water type, and concentration. 

Table VIII. Mass Balance Data and Estimates of Solute Recovery (Test Run 618-41) Cellulose Acetate Membrane Concentration without Humics...

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