Recovery Measurements

Moisture recovery Measures taken to prevent the moisture present in the air from leaving the treated space. 

There are several measure sets with immediate payback SE, SF, SH, SI. Measures SE and SF are radiant panel systems with displacement ventilation. These systems have a similar cost to the base case, but they offer energy savings. Furthermore, significant sizing reductions, mainly in the cooling tower and chiller sizes, offset the incremental cost of the envelope and heat recovery measures. Because the elevator efficiency measures offer a net savings in capital cost, the capital cost of the other measures is further offset. 

Kusumi, A., W. K. Subczynski, and J. S. Hyde. 1982b. Oxygen transport parameter in membranes as deduced by saturation recovery measurements of spin-lattice relaxation times of spin labels. Proc. Natl. Acad. Sci. USA 79 1854-1858. 

For tensile creep, TJ would be the tensile viscosity. When the viscosity is high (e.g., when working at relatively low temperatures or with very high-molecular-weight polymers) it can be difficult to determine tl-x accurately, so creep recovery measurements are made. Here the load is released after a given creep time and the strain is followed as the specimen shrinks back toward its new equilibrium dimensions. 

Recovery measurements are one of the most difficult aspects in organic analysis. These measurements are often completed, with the minimum number of replicate determinations over a limited concentration range, to justify optimistically the use of a method. Experiments designed to obtain the efficiency of the analytical method often implicitly assume that this also includes the efficiency of extraction from the matrix [366]. 

Regular, routine sample recovery measurements can be made by using the method of standard addition. The matrix is spiked with the analytes in a small volume of solvent at a level which is 50%, 100%, 150%, and 200% above the estimated level in the sample. A number of independent replicates should be made at each level. Provided that sufficient material is available the sample can be analyzed prior to spiking. In case of limited size (e. g., small tissue samples) a number of samples may be pooled and homogenized for such recovery experiments. 

Isotope dilution mass spectrometry (IDMS) is another method to overcome the problem of sample recovery [370-372]. The 13C-labeled isotope of the analyte is added to the sample at the commencement of the analysis and the ratio of the labeled and unlabeled compound is measured by MS. This technique eliminates the need for recovery measurements and automatically accounts for any losses in the determination [373]. The two major limitations of this method are the cost and availability of the labeled compounds and the need to use the MS as a detector. 

Foamed blends of ethylene-styrene interpolymer and LDPE were subjected to a range of mechanical tests, including compressive impact testing, Instron compression and Poisson s ratio measurements, compressive creep measurements and compression set and recovery measurements. The data obtained were compared with those for EVA and the suitability of these foamed blends as replacements for EVA in the manufacture of soccer shin guards and midsoles for sports shoes was evaluated. 20 refs. 

An interesting new experimental approach has been taken in order to separate overlapping EPR spectra as they appear e.g. in the multi Fe/S centre containing complex I. Inversion- and saturation-recovery measurements which allow to measure Ti relaxation times are used in a inversion-recovery filter which is subsequently applied to separate EPR signals on account of their Trdifferences. In addition, this filter can be used in conjunction with high-resolution hyperfine measurements e.g. by ESEEM and thus the separated centres can be characterized in depth.211... 

In subunit R2 of ribonucleotide reductase there is a tyrosyl radical (Y ) in close proximity to a di-iron cluster.100 In the protein from E. coli the EPR signal from Y can be observed up to room temperature. However, in the protein from yeast the Y signal broadens above 15 K and is not observable above about 60 K. Saturation recovery measurements at 140 GHz showed that at 60 K the spin-lattice relaxation rates for the Y signal in the yeast protein were about 2 orders of magnitude faster than for the E. coli protein. The temperature dependence of the relaxation enhancement was consistent with the activation energy for the first excited state of the di-iron cluster, so the relaxation enhancement was attributed to interaction with the di-iron cluster. Relaxation enhancements measured at 140 GHz showed little orientation dependence so the enhancement was assigned to isotropic exchange, which is different from the orientation-dependent dipolar interaction observed for the E. coli protein.100... 

Note ind denotes individual, and mix denotes mixture values in parentheses are the percent recovery measured in the effluent. 

Fig. 1. a) Formation of the geminate ion pair upon electron transfer b) Energy diagram for ground state recovery measurements on the electron transfer product. 

In order to obtain an impression as to the usefulness of eqs. (1.6), (2.11) and (2.20), measurements have, amongst others, been carried out on polymer melts. These materials seem particularly suitable for the determination of shear recovery, as the problems arising in connection with the inertia of parts of the apparatus become much less important than with polymer solutions of low and intermediate concentrations, on which previous measurements have been carried out. In fact, the viscosity of polymer melts is, in general, very much higher than that of the mentioned solutions. At this Institute, Den Otter (26) carried out shear recovery measurements on polymer melts with the aid of a simple cone-and-plate arrangement. 

Surrogate standard recovery measures analytical accuracy for each individual sample. Approved methods for organic compound analysis usually recommend the surrogate standard selection. Similar to target analytes, multipoint calibration curves are prepared for surrogate standards. 

If sorption is 50% efficient but desorption is 100% efficient, the recovery measured is 50%> and it is impossible to know whether sorption or desorption was inefficient or if reduced recovery was produced by a combination of both. Therefore, method development requires either optimizing sorption while controlling desorption, or vice versa using an iterative approach [67,72], Alternatively, a statistical factorial design can be used to determine and optimize quickly variables important to SPE [110]. Using either approach, it is important to consider the major factors influencing retention, including sample pH, sample volume, and sorbent mass. 

The electrical stability of the TFT was measured using dc bias followed by a pulsed recovery measurement. The dc bias conditions were applied with the gate potential set at 20 V and the source/drain bias at 1 V. The devices were stressed for 60 min followed by the pulsed recovery measurement having an on-time pulse of 25 ms. and an off time of 10 s. Figure 11.17 shows the measurement of the... 

Fig. 11.17. Drain current as a function of time for dc and pulsed gate bias conditions. The TFT in this case was biased for 3600 s before pulsed recovery measurements were started.

On another hand, migration energies calculated in Ref. [6] differ significantly from the isothermal residual resistance recovery measurements obtained by authors in Refs. [5] (0.45 eV), [10] (0.43 eV) and from the Gorsky effect determination with self-diffusion of H in Lu [11] (0.575 eV). Why does such a discrepancy exist ... 

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