Interface parameter

With regard to quantitative measurements of APG surfactants in, e.g. environmental samples, the authors stressed that it was of crucial importance to promote the formation of the desired molecular (or adduct) ion in order to obtain reproducible mass spectra. If tuning of the ESI interface parameters did not suffice to yield abundant ions of the selected species, acquisitions of the mass spectrometric detector after negative ionisation in conjunction with appropriate selection of the mobile phase composition were used as an alternative despite the lower sensitivity in this mode [1,2],... 

In (—)-ion mode besides the [M — H] the chloride adduct also appeared in the MS spectra with a similar intensity, but optimisation of the ESI interface parameters allowed the formation to significantly shift towards the [M — H] ion, while the chloride adduct was largely suppressed. The molecular ion yielded two fragments, one including the alkyl chain [CH3-N-CO-R]-, the other the sugar part [Gluc-N-CH3]. ... 

An atmospheric pressure chemical ionization (APCI) interface is generally considered extremely easy to optimize and operate. This is perhaps best proven by the fact that hardly any optimization of the interface parameters is reported... 

An additional complication is the often experimentally detected dependency of the frequency of bulk and interface parameters. Up to now, discussion of this phenomenon has attributed it to causes such as poor uniformity at microscopic scale, but other causes are also possible. More attention is given to this problem on pages 55-56. 

EIS has proven to be a useful technique for the analysis of electrochemical systems, such as corrosion systems and batteries. In comparison with DC electrochemical techniques, EIS has tremendous advantages, as it can provide a wealth of information about the system being studied. Also, due to the small perturbation in the AC signal, the electrode response is in a linear potential region, causing no destructive damage to the electrode. Therefore, EIS can be used to evaluate the time relation of interface parameters. 

The FBI is preferentially operated at flow-rates between 0.1 and 0.5 ml/min, thus fitting the optimum flow-rates of a 2-mm-ID column. The FBI can be used in combination with both normal-phase and reversed-phase mobile phases. In reversed-phase LC, the optimum settings of most interface parameters are very much influenced by the water content of the mobile-phase. In general, the best response is obtained with a mobile phase with a high organic modifier content a 70% loss in response between pure methanol and pure water was reported for methylene blue, furosemide, spectinomycin, and 2-chloro-4-iutrobenzamide [90]. 

In general, ESI is considered more difficrrlt to operate than APCL ESI is more sensitive to solvent composition and additives. APCl does not appear to need significant optimization of interface parameters. Nevertheless, at least 90% of the LC-MS applications are performed using ESI. 

Janusz, W., Adsorption of sodium and chloride ions at the rutile/electrolyte interface—parameters of the electric double layer. Mater. Chem. Phys., 24, 39, 1989. 

Several interface parameters, which characterize its band profile are also indicated in fig. 1 The meanings of these parameters are the same as that presented in Kim s paper. 

The concentration profile in the immobile-water phase is controlled by a diffusional-transport mechanism. The transfer rate from the immobile-water phase to the flowing-water phase is the diffusive flux, which depends on the concentration gradient in the immobile-water phase at the interface. Parameters V, 6, A, and Lg in the profile side-pore model are estimated from the shape of the breakthrough curve for a nonreactive tracer. Parameters Pbf and pbs are estimated from the shape of the breakthrough curve for a reactive solute. The effective molecular diffusivity Dm is estimated from values published in the literature. 

Control of an accessory Set RS232C interface parameters (baud rate, parity, etc.)... 

These declarations are for the function arguments, the interface parameters passed to function scfl. 

The table reports only some mean values of some interface parameters. 

Sm is the interface parameter representing the extent of Fermi level stabilization for a given organic semiconductor (t)o is a material property... 

Eg is the energy gap of the organic semiconductor Interface parameter Sm is formulated by... 

From a viewpoint of chemistry, charge transfer can associate with chemical interaction between the metal and the organic semiconductor. The electronegativity difference of two materials determines the strength of the chemical bonding and thus the barrier height. According to the derivation proposed by Louie et al. [22], the interface parameter S can be expressed as... 

Experimental (S p,) and Calculated (S i) Values of the Interface Parameter S at Metal/Organic Interfaces... 

Enable a pen plotter and provide proper serial interface parameters for the device. 

Where IF is the specimen thickness, a is a the notch length, B is the width of the specimen, S is the distance between the supports, Po is the failure load of a specimen placed without fiber, Z,/is the length of the fiber, df is the diameter of the fiber, Vf is the volume fraction of the fiber, g is the interface parameter, ris fiber/matrix shear stress, and f(a/W) is the shape function calculated as follows Eq.2 ... 

Gassan J (2002) A study of fibre and interface parameters affecting the fatigue behaviour of natural fibre composites. Compos A 33 369-374... 

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