We present a review on the accuracy of asymptotic models for the scattering problem of electromagnetic waves in domains with thin layer. These models appear as first order approximations of the electromagnetic field. They are obtained thanks to a multiscale expansion of the exact solution with respect to the thickness of the thin layer, that makes possible to replace the thin layer by approxima...

There has been a tendency to discount thin-layer chromatography (TLC) in recent years because of the availability of high-performance liquid chromatography (HPLC) methods that appeared to offer greater versatility and ease of quantification, amongst other reasons. However, TLC has made a comeback, largely because of the high reproducibility and lower costs of commercial pre-coated plates. It is...

Thin layer chromatography (TLC) is a useful technique for the separation and identification of compounds in mixtures. TLC is used routinely to follow the progress of reactions by monitoring the consumption of starting materials and the appearance of products. Commercial applications of TLC include the analysis of urine for evidence of "doping", the analysis of drugs to establish purity or ident...

Ceramides with mono-, di-, and trihydroxy long-chain bases, and normal (saturated and unsaturated), branched-chain, and 2-hydroxy fatty acids have been analyzed by thin-layer chromatography. In most cases the compounds were also run as acetates. Borate, arsenite, and silver ions were used as complexing agents, and the effects of number, position, and stereochemistry of hydroxy groups, and of un...

The various OPLC andRPC techniques are compared in Table 1. Study of the data shows that OPLC is an excellent technique for analytical separations and that RPC is more ideally suited as a preparative method for isolation of compounds from biological matrices. The advantage of combining online and ofSine separations and two-dimensional development can also be exploited in OPLC. The advantage of ...

During the hypersonics activities of the 1960s, thin shock-layer theory was developed as a rst-order correction to Newtonian theory, in the hope of gaining insight into eÆcient lift at very high speeds. The wings are limited to conical geometry, but can have arbitrary transverse camber. Good predictions were made of the forces generated by delta and caret wings, but no optimization studies were...

Cllromatcqgq~ily has its main application in solving analytical problems, but since it can lx-oducc essentially l)ure conq~ounds, prcl~arativc methods are of interest for synthetic \vork, for those identification techniques which riced nig amounts and for isolation of minor constituents in mistures. " Scaling-up " of the separation can be effect4 by cnlargemcnt of dimensions, by reiteration of ...

Abstract. In this paper, we propose a uniaxial perfectly matched layer (PML) method for solving the time-harmonic scattering problems in layered media. The exterior region of the scatterer is divided into two half spaces by an infinite plane, on two sides of which the wave number takes different values. We surround the computational domain where the scattering field is interested by a PML layer...

A thin-layer acrylamide gel electrophoresis technique suitable for analysis of serum or urine proteins is described in detail. The method gives sharp differentiation of protein fractions and is particularly suitable for the analysis of biological solutions containing proteins in low concentration.

Na2CO3. After 1 mm, 1.0mL of alkaline picrate reagent (500 mL saturated picric acid, 100 mL of 1 mol/L NaOH, and 1 mL of Triton X-100 per liter) is added. The absorbance change at 505 nm and 37 #{176}C is measured between 48 s and 7 mm after adding the picrate reagent. Under these conditions, samples of pooled sera from jaundiced patients showed negative interference, 35 mg of total bilirubin p...