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Buffer technique

A buffer technique called bit reservoir was introduced to satisfy this additional need for bits. It can be described as follows ... [Pg.334]

Huebner, J.S., 1971, Buffering techniques for hydrostatic systems at elevated pressures, in G.C. Ulmer, ed.. Research Techniques for High Pressure and High Temperature New York, Springer-Verlag, pp. 123-177. [Pg.576]

Stable in water), so we need a way of controlling /g o i range of, say, 25-100 °C. A convenient way to do this is with the humidity buffer technique. Consider, for example, the calcanthite-bonattite reaction, which is... [Pg.249]

A very important feature of capsule techniques in quenching experiments is the possibility of using the buffers. Buffers are flie additional phases placed in a charge capsule or in the second capsule in the experiments with hydrothermal systems to control the activity of some components. Most often it is tiie acidity of aqueous fluid. This approach to the study of natural hydrothermal systems, where the activity of one (or several) of the system s component(s) (for example pH or fugacity of O2, H2, S2, CO2) is under control of special reactions, was developed by Eugster (1957) and is widely used in experimental geochemistry. Details of the buffer technique have been reviewed by Huebner (Ulmer, 1971) and by Eugster et al. (Ulmer and Barnes, 1987). [Pg.81]

In 1965, the Dubna workers found a longer-lived lawrencium isotope, 256Lr, with a half-life of 35 s. In 1968, Thiorso and associates at Berkeley used a few atoms of this isotope to study the oxidation behavior of lawrencium. Using solvent extraction techniques and working very rapidly, they extracted lawrencium ions from a buffered aqueous solution into an organic solvent — completing each extraction in about 30 s. [Pg.215]

There are several forms of electrophoresis. In slab gel electrophoresis the conducting buffer is retained within a porous gel of agarose or polyacrylamide. Slabs are formed by pouring the gel between two glass plates separated by spacers. Typical thicknesses are 0.25-1 mm. Gel electrophoresis is an important technique in biochemistry, in which it is frequently used for DNA sequencing. Although it is a powerful tool for the qualitative analysis of complex mixtures, it is less useful for quantitative work. [Pg.597]

Capillary Electrochromatography Another approach to separating neutral species is capillary electrochromatography (CEC). In this technique the capillary tubing is packed with 1.5-3-pm silica particles coated with a bonded, nonpolar stationary phase. Neutral species separate based on their ability to partition between the stationary phase and the buffer solution (which, due to electroosmotic flow, is the mobile phase). Separations are similar to the analogous HPLC separation, but without the need for high-pressure pumps, furthermore, efficiency in CEC is better than in HPLC, with shorter analysis times. [Pg.607]

Thermospray interface. Provides liquid chromatographic effluent continuously through a heated capillary vaporizer tube to the mass spectrometer. Solvent molecules evaporate away from the partially vaporized liquid, and analyte ions are transmitted to the mass spectrometer s ion optics. The ionization technique must be specified, e.g., preexisting ions, salt buffer, filament, or electrical discharge. [Pg.433]

The hberated iodine is measured spectrometricaHy or titrated with Standard sodium thiosulfate solution (I2 +28203 — 2 1 VS Og following acidification with sulfuric acid buffers are sometimes employed. The method requires measurement of the total gas volume used in the procedure. The presence of other oxidants, such as H2O2 and NO, can interfere with the analysis. The analysis is also technique-sensitive, since it can be affected by a number of variables, including temperature, time, pH, iodide concentration, sampling techniques, etc (140). A detailed procedure is given in Reference 141. [Pg.503]

LB Films of Long-Chain Fatty Acids. LB films of saturated long-chain fatty acids have been studied since the inception of the LB technique. The most stable films of long-chain fatty acids are formed by cadmium arachidate deposited from a buffered CdCl2 subphase. These films, considered to be standards, have been widely used as spacer layers (23) and for examining new analytical techniques. Whereas the chains are tilted - 25° from the surface normal in the arachidic acid, CH2(CH2) gCOOH, films (24), it is nearly perpendicular to the surface in the cadmium arachidate films (25). [Pg.533]

Distinction is also made among electrophoretic techniques in terms of the type of matrix employed for analysis. Matrices include polymer gels such as agarose and polyacrjiamide, paper, capillaries, and flowing buffers. Each matrix is used for different types of mixtures, and each has unique advantages. [Pg.178]

Disc electrophoresis was first iatroduced ia the early 1960s (11—13) as various techniques using polyacrylamide gels were being explored and designed. Original work employed several buffer systems and different polyacrylamide gels in order to first concentrate and then separate compounds (14). [Pg.181]

Biological activity (BA) was chosen as such parameter. The BA determined using a system and a technique for a class of natural polyphenolic bonds nicotinamide adenine dinucleotide restored (NAD H ) - ferricyanide (KjFe(CN)g) in a phosphates buffer solution. [Pg.213]

All of these techniques are available, but have not been well researched in terms of their nutrient removal efficiency. One exception is the recent work on the efficiency of buffer zones, which used figures of 10-15% for nitrogen and 20-30% for phosphorus reduction by wooded buffer zones in a study of the Slapton Tey catchment. [Pg.37]

Gas compressors operating on highly toxic or flammable gases may require redundant systems to assure no leakages. In many applications, such as refrigeration gas, buffer seals are required with the liquid-buffered face seal. A popular technique is to use a buffered labyrinth seal with a liquid seal. [Pg.513]


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See also in sourсe #XX -- [ Pg.112 ]




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