Alternative Analysis

This method is the usual one for analysing the manganese content of steel. The initial step is to oxidise and remove organic matter (or O in steels). Persulphate then oxidises Mn to permanganate. The latter is then determined spectrophotometrically when dilution is necessary to obtain an optimum absorbance. The modification discussed in Sec.2.4.1 for strongly absorbing solutions could be used here. 

A quick alternative method is based on the reduction of Mn(lll) by an excess of Kl, titrating the liberated iodine with standardised thiosulphate. 

If the solvent extraction of Mn(IlI) described above is repeated with fresh Mn(III) sulphate solution and the coloured organic layer is allowed to evaporate in a vacuum desiccator, a solid compound is obtained. 

Thoroughly mix 12 cm of dibutylphosphate with 60 cm of toluene in a separating funnel. Add 50 cm of Mn2(S04)3 solution prepared as above and shake well. Discard the aqueous layer and use a fresh aliquot of Mn(IIl) solution and extract as before. Repeat the extraction to obtain maximum colour production in the organic layer. Transfer to an evaporating basin and allow to evaporate in a vacuum desiccator with an efficient desiccant. Separate the solid by filtration under suction, quickly weigh the solid and store in a vacuum desiccator since it is sensitive to moisture. 

Weigh accurately a portion of the solid into a conical flask, add 10% Kl solution until no more iodine is liberated. Titrate against standardised 0.01 M thiosulphate, adding the freshly prepared starch solution when the colour is straw yellow. Continue titration until 

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An alternative analysis of eolloidal interaetion and stability based on elassieal solution thermodynamies has been proposed independently by Hall (1972) and Ash etal. (1973) and the praetieal implieations with partieular interest in the effeets of polymers and surfaetants has been diseussed by Pethiea (1986). In this theory, the forees between partieles are governed in a straightforward way by the adsorptions of the eomponents of the system and their dependenee of partiele separation and ehemieal potentials (whieh are defined by the eomposi-tion) aeeording to the equation... 

More recently, D. Emin [24] developed an alternative analysis of activated hopping by introducing the concept of coincidence. The tunneling of an electron from one site to the next occurs when the energy state of the second site coincides with that of the first one. Such a coincidence is insured by the thermal deformations of the lattice. By comparing the lifetime of such a coincidence and the electron transit time, one can identify two classes of hopping processes. If the coincidence lime is much laigcr than the transit lime, the jump is adiabatic the electron has lime to follow the lattice deformations. In the reverse case, the jump is non-adia-batic. 

The alternatIve analysis via convent ional condensat ions and I GA on (5) reveals just how much of a short cut this cyclisation is. 

Dealing with incomplete extraction is particularly challenging when analysing polymers containing unknown additive levels. A common strategy is to perform multiple extractions. When incomplete extraction is suspected, it is also useful to apply an alternative analysis technique, such as spectroscopy or elemental analysis. It is good practice to compare the IR spectrum of the polymer before and after extraction to verify the presence of absorbance bands related to the additive. 

Later on in this chapter, under the heading Alternate Analysis we present the new analysis, as recommended. 

Delfin, F.G. Jr. Pioquinto, W.P.C. 1999. Alternative analysis of reservoir permeability in the Mt. Apo geothermal project. PNOC-EDC Internal Report, 1999. 

This mechanistic question is one of the examples of the success of density functional theory methods in organometallic chemistry. Earlier work on the reaction mechanism could not discriminate between the two alternatives. Analysis of the different orbitals based on extended Hiickel calculations came to the result that the [3+2] pathway is more likely, but could not exclude the possibility of a [2+2] pathway [13]. Similar conclusions where obtained from the results of Hartree-Fock calculations in combination with QCISD(T) single point calculations [21], Attempts to use Ru04 as a model for osmium tetraoxide indicated that the formation of an oxetane is less favorable compared to the [3+2] pathway, but still possible [22, 23],... 

The standard urine immunoassay for detection of cocaine (23a) abuse during the gestation period of newborn babies was frequently found to yield negative results in cases where positive results were shown by extraction of meconium with a solvent, followed by HPLC. The drug and metabolites such as norcocaine (23b) and cocaethyline (23c) were detected140. See Section IV.C for an alternative analysis of cocaine. 

Campbell, G.A., Spalding, M.A., and Tang, Z., An Alternative Analysis of Single-Screw Melting, SPE ANTEC Tech. Papers, 55, 147 (2009)... 

Fig. 2. Stratified analysis design for evaluating a new experimental treatment (E) relative to a control (C). The status of a biomarker based classifier of the likelihood of responding to E is utilized in a prospectively specified analysis plan. The biomarker classifier is not just used for stratifying the randomization. Alternative analysis plans are described in the text.

The DfE Program and its partners fully exercised the principles of informed substitution for the first time in the alternatives analysis for pentabromodiphenyl ether, as part of its Furniture Flame Retardancy Partnership [9]. The analysis brought together a diverse stakeholder group, elicited new data from flame retardant manufacturers, and created an informative summary of experimental and modeled data. The industry used the data from the report as part of their move to safer alternatives. 

An alternative analysis having a long history, however, is to simply plot In A vs. 1/ T, this procedure being motivated by the empirically derived Arrhenius expression... 

Because the presence of preexisting glucose and maltodextrins in a sample can lead to overestimation, sample blanks can be run in parallel without treatment with amylase enzymes (step 3a) as a control. Alternatively, analysis of the sample blank can be avoided by preextracting samples with 80% ethanol (step 3b). 

Estes TJ, Schroeder PR, Loikets WR, Taylor ER, Agrawal V, Caine C, Gallas R (2003) Indiana harbor and canal dredging and disposal alternatives analysis Evaluation of relative disposal requirements, emissions and costs for mechanical and hydraulic dredging alternatives. US Army Engineer Research and Development Center... 

An alternate analysis was performed using dose as a surrogate for risk. Using the same assumptions given above and the RESRAD code, the dose to an intruder was estimated to be 15 mSv. Assuming an allowable dose of 20 mSv (see Table 7.1), the risk index was estimated to be 0.8. Therefore, as expected, either approach yields about the same result. 

Dann, G.M.S. (1996b) Tourists image of destination An alternative analysis. Journal of Travel and Tourism Marketing 5 (1), 41-55. 

The molecular processes that take place during polymer crystallization can be investigated from different viewpoints. A global approach determines the shape and conformation of chains in the polymer melt, and infers processes that lead to the lamellar chain folded crystal. Alternatively, analysis of the final crystal structure may help us to work backwards and gain insights into processes that take place in the last stages of crystal build-up. It is clear, however, that the two approaches should lead to the same conclusions, since the crystallization processes that occur should not, and certainly do not, depend on the viewpoint adopted for their analysis. 

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