Recovery level

Continuing calibration for a Series Method is performed using calibration check compounds. Surrogate compounds are added to the matrix before sample preparation to evaluate recovery levels. To check GC retention times, internal standards are added to a sample after its preparation for analysis. 

Figure 52 also shows that the actual recovery curve does not decrease below a certain level. This indicates that a certain amount of material is always recovered to the underflow and bypasses classification. If a comparison is made between the minimum recovery level of solids to the liquid that is recovered, they are found to be equal. Therefore it is assumed that a percent of all size fractions reports directly to the underflow as bypassed solids in equal proportion to the liquid split. Then each size fraction of the actual recovery curve is adjusted by an amount equal to the liquid recovery to produce the "corrected recovery" curve shown in Figure 52. As the Djoc point changes from one application to another, the recovery curves shift, along the horizontal axis. In order to determine a single graph which represents the corrected recovery curve, the particle size of each size fraction is divided by the Dj value and a "reduced recovery" curve can be plotted, as shown in Figure 53. Studies reported by Arterburn have shown that this curve remains constant over a wide range of cyclone diameters and operating conditions when applied to a slurry...

The.se plants are not as popular as they once were and are rarely, if ever, constructed anymore. They are very difficult to operate, and it i> difficult to predict their efficiency at removing liquids from the gas as the lean oil deteriorates with time. Typical liquid recovery levels are ... 

By decreasing the pressure and increasing the bottoms temperature more methane and ethane can be boiled off the bottoms liquid and the RVP of the liquid stream decreased to meet requirements for sales or further processing. Typical liquid recovery levels are ... 

Because of the lower temperatures that are possible, cryogenic plants have the highest liquid recovery levels of the plants discussed. Typical levels are ... 

The eurrent and future levels of plastic packaging recycling is discussed with reference to the imminent updating of the 1994 Paekaging and Packaging Waste Directive. Data are ineluded relating to current recovery levels by eountry for western Europe, for mechanical and... 

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%. 

High compatibility of the additive with the polymer matrix usually extends performance but at the expense of extractability. Lack of extractability is of analytical concern, e.g. in case of functionalised oligomer and polymeric additives, grafted and reactive additive functionalities, and chemisorbed and absorbed additives. More generally, additive recovery levels significantly lower than the target level may arise from various situations ... 

Persimmon fruit slices stored under air showed a decrease in carotene content (Wright and Kader 1997a). The air + 12% carbon dioxide treatment resulted in a loss of cryptoxanthin over the first 3 days, followed by a slight recovery. Levels of carotene... 

Wilson [337] showed that liquid-liquid extraction of estuarine water immediately after addition of DDT gave acceptable recovery levels with all solvent systems tested, but analyses carried out several days later gave only partial recovery owing to adsorption of DDT on suspended matter. 

The potassium chloride and potassium sulphate system was studied. The results of tests carried out (Table 11.2) showed that the recovery levels of potassium chloride permeate were excellent at the higher operating temperatures, with almost perfect rejection of potassium sulphate. The SRS skid could be designed for use in the caustic potash industry and recover potassium chloride from effluent purges. 

The Claus Catalytic Cbnverters. These units represent the heart of any sulfur recovery plant. While the bulk of the sulfur yield may be obtained in the front end reaction furnace the high overall recovery levels demanded by environmental regulations are largely dependent on the efficiency of the Claus catalytic converters. 

It should be pointed out here that most biochemical separation methods that have been developed in research laboratories cannot necessarily be practiced on an industrial scale, so as to achieve high recovery levels. Rather, innovative approaches are often necessary in these industrial processes to achieve separations that ensure high purity and good recovery of the target product. 

Recovery levels for individual organic compounds were, as expected, less than the values predicted by using the membrane solute rejections. Differences in the actual recovery and the theoretical recovery were partially due to adsorption losses. Mass balance analysis still indicated a deficiency in some cases. Rectification of the inconsistencies in these data was complicated by the limited water solubility of compounds chosen for study, the necessity of using a cosolvent in spiking, and, in particular, the limitations of the analytical procedures at these extremely low concentrations. 

Although economics may favor plan A, the final decision on which plan to pursue will likely be based on a management value judgment. This judgment must consider all capita] expenditure, oil-recovery level, and risk of... 

Figure 2.1. Percentage of adsorbed Cd or Zn ions extracted from humic acid suspensions by electrolyte solutions. W Humic acid I El Humic acid II. Symbols indicate mean SD. The lettered entries indicate systems in which the addition of clay particles (i = illite, m = montmorillonite) altered the recovery level. From [257]...

Hasson, D., Drak, A. and Semiat, R. (2001) Inception of CaS04 scaling on RO membranes at various water recovery levels. Desalination, 139, 73-81. 

In addition to the MF pretreatment, used to remove particulates and microorganisms from raw water, reducing membrane fouling in the successive steps, the NF step is able to reduce water hardness decreasing osmotic pressure of the RO feed, allowing operation at higher water recovery level. 

Although the recovery of the polytartrate ligand by filtration amounts to about 90%, the Ti recovery levels are significantly lower (34). The fact that part of the Ti remains in the solution means that the binding of Ti to the anchored ligand is less efficient than it is to the ligand in solution. It seems unlikely that the polymeric nature of the ligand allows the formation of the same 2 2 Ti tartrate complexes that are formed in solution. Moreover, no recycle experiments have provided evidence that the catalyst is reusable. 

Various factors require definition when using the LC-MS in a quantitative mode. These include stability testing of the analyte in the sample matrix, selectivity, sensitivity, or level of detection, the limit of quantitation, and recovery levels from the sample matrix. 

Receive status reports from and develop an Incident Action Plan with Section Chiefs and Command Staff to determine appropriate response and recovery levels. During initial briefing/status reports, discover the following ... 

Tyr and Lys residues were suggested to have been crosslinked to form the active site cofactor since they were not detectable at the expected recovery level during Edman sequencing. This was further supported by mutagenesis studies which are discussed in the full paper (13). 

The accuracy of the method was studied by recovery experiments. The recovery experiments were performed by adding known amounts of the dmgs into a placebo. The recovery was performed at three levels (80%, 100%, and 120%) of the label claim per tablet (500 mg of metformin HCl and 5 mg of glibenclamide). Three samples were prepared for each recovery level. The recovery values for metformin HCl and ghbenclamide ranged from 98.5% to 99.9% and from 99.3% to 101.2%, respectively (Table 1). The average recovery of three levels (nine determinations) for metformin HCl and ghbenclamide were 99.2% and 100.0%, respectively. 

Recovery level Anvnunt Spiked (MK of analyte/ g of wmid) Amount measured (pg of analvle/g of wood)... 

Recovery level Anxtunt Ivpiked (mk of analyte/ e of wood) Aiituunl measured tig of analyte/g of wood)... 

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