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Dry methods

An alternative approach to peptide sequencing uses a dry method in which the whole sequence is obtained from a mass spectrum, thereby obviating the need for multiple reactions. Mass spec-trometrically, a chain of amino acids breaks down predominantly through cleavage of the amide bonds, similar to the result of chemical hydrolysis. From the mass spectrum, identification of the molecular ion, which gives the total molecular mass, followed by examination of the spectrum for characteristic fragment ions representing successive amino acid residues allows the sequence to be read off in the most favorable cases. [Pg.333]

Drying capability Drying index Drying mechanisms Drying methods Drying oil Drying oils... [Pg.347]

Unless working with superdried systems or in the presence of proton traps, adventitious water is always present as a proton source. Polymeriza tion rates, monomer conversions, and to some extent polymer molecular weights are dependent on the amount of protic impurities therefore, weU-estabHshed drying methods should be followed to obtain reproducible results. The importance is not the elimination of the last trace of adventitious water, a heroic task, but to estabhsh a more or less constant level of dryness. [Pg.244]

The Megalopohs station (Fig. 4d) uses hot flue gas to dry the lignite. A cyclone separator and electrostatic precipitator permit rejection of some of the water vapor to the atmosphere rather than to the boiler. Another drying method uses a vertical shaft, heated by combustion gases, for partial drying prior to grinding. [Pg.156]

Chemical Analysis. Plasma oxidation and other reactions often are used to prepare samples for analysis by either wet or dry methods. Plasma excitation is commonly used with atomic emission or absorption spectroscopy for quaUtative and quantitative spectrochemical analysis (86—88). [Pg.114]

Production of net-shape siUca (qv) components serves as an example of sol—gel processing methods. A siUca gel may be formed by network growth from an array of discrete coUoidal particles (method 1) or by formation of an intercoimected three-dimensional network by the simultaneous hydrolysis and polycondensation of a chemical precursor (methods 2 and 3). When the pore Hquid is removed as a gas phase from the intercoimected soHd gel network under supercritical conditions (critical-point drying, method 2), the soHd network does not coUapse and a low density aerogel is produced. Aerogels can have pore volumes as large as 98% and densities as low as 80 kg/m (12,19). [Pg.249]

Moisture. Moisture is usually determined by a vacuum oven-dry method at 80°C. Moisture levels of more than 0.05% are likely to lead to caking or lumping problems which can make storage and transfer of bulk sugar difficult. The usual standard is 0.03%, which manufacturers can easily meet. Care must be taken to avoid temperature differentials ia storage which cause moisture to migra te and estabUsh pockets of unacceptably high moisture levels. [Pg.30]

Special drying methods, such as superheated steam, solvent, vacuum, infrared radiation, and high frequency dielectric and microwave heating, are occasionally employed when accelerated drying is desired and the species being dried can withstand severe conditions without damage. None of these methods is of significant commercial importance. [Pg.324]

Electrolytic Processes. The electrolytic procedures for both electrowinning and electrorefining beryUium have primarily involved electrolysis of the beryUium chloride [7787-47-5], BeCl2, in a variety of fused-salt baths. The chloride readUy hydrolyzes making the use of dry methods mandatory for its preparation (see Beryllium compounds). For both ecological and economic reasons there is no electrolyticaUy derived beryUium avaUable in the market-place. [Pg.67]

The dry method for synthesizing metal carbonyls from salts and oxides has proven very usehil in a number of cases. The metal carbonyl is formed in the presence of a suitable reducing agent. In some cases CO itself is the reducing agent. Rhenium (97) and technetium (98,99) carbonyls are conveniently... [Pg.67]

Green coffee processing is effected by either the dry or wet method. The dry method produces so-called natural coffees. The wet method usually produces the more uniform and higher quaUty washed coffees. [Pg.384]

Use alternate drying method (ex. vacuum drying instead of atmospheric drying vacuum tray dryer, freeze drying, cryogenic CO2 drying, instead of vacuum rotary dryer) where material is subdivided in multiple locations... [Pg.72]

Electrostatic method This is also a w et method like the conventional process, except that the paint is now electrostatically charged, similar to the powder ptiint in a dry method as discussed later. The paint, being highly charged electrostatically, is wrapped around the object automatically. [Pg.405]

When the desired halide is hydrolytically unstable then dry methods must be used, often at elevated temperatures. Pre-eminent amongst these methods is the oxidative halogenation of metals (or non-metals) with X2 or HX when more than one oxidation state is available X2 sometimes gives the higher and HX the lower, e.g. ... [Pg.822]

When produced by such dry methods it is frequently unreactive but, if precipitated as the hydrous oxide (or hydroxide ) from aqueous chromium(III) solutions it is amphoteric. It dissolves readily in aqueous acids to give an extensive cationic chemistry based on the [Cr(H20)6] ion, and in alkalis to produce complicated, extensively hydrolysed chromate(III) species ( chromites ). [Pg.1007]

The difference between the specific surface areas of materials treated by the wet or dry method can also be explained by the rewelding mechanism. The surface area of wet milled powders continuously increases during milling, while extended dry milling causes a decrease in surface area. [Pg.261]

For substances with particles of 20 microns and coarser, sieving with these sieves is possible in many cases by the normal dry methods. To obtain optimum results, however, it is advisable... [Pg.508]


See other pages where Dry methods is mentioned: [Pg.932]    [Pg.460]    [Pg.17]    [Pg.368]    [Pg.380]    [Pg.82]    [Pg.9]    [Pg.343]    [Pg.112]    [Pg.118]    [Pg.249]    [Pg.251]    [Pg.365]    [Pg.461]    [Pg.384]    [Pg.384]    [Pg.243]    [Pg.1233]    [Pg.1238]    [Pg.474]    [Pg.531]    [Pg.951]    [Pg.1120]    [Pg.1211]    [Pg.46]    [Pg.905]    [Pg.234]    [Pg.629]    [Pg.641]    [Pg.858]    [Pg.53]    [Pg.71]   
See also in sourсe #XX -- [ Pg.321 ]




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Air-dried methods

Applications of drying methods

Bulk modulus, drying methods

CRYOGENIC AND DRYING METHODS

Calculation Methods for Constant-Rate Drying Period

Calculation Methods for Falling-Rate Drying Period

Chemical methods of petroleum drying

Conduction drying methods

Convection drying methods

Convective drying methods

Critical point drying method

Dip-dry method

Dried droplet method

Dried-down solution method

Dried-droplet method, preparation

Drop-dry method

Dry ashing method

Dry cleaning method

Dry flow method

Dry gel method

Dry granulation, methods

Dry other methods

Dry processing method

Dry sieving method

Dry-film method

Drying Karl Fischer method

Drying Methods for Gels - Quality Loss

Drying electrical methods

Drying experimental methods

Drying methods

Drying methods

Drying methods aspen

Drying methods conversion

Drying methods dimensional change

Drying methods hardware

Drying methods industrial dryers

Drying methods kilns

Drying methods whole-tree

Drying methods with stack gases

Drying methods wood products

Drying methods, diethyl phthalate

Drying methods, diethyl phthalate magnesium ethoxide

Drying methods, plant material

Drying techniques aqueous method

Drying techniques organic method

Fractionation methods freeze-drying

Freeze drying method

Freeze-drying method polymerization

Freeze-drying treatment method

Freezing and drying methods

Grain-drying methods

Heat drying method

Introduction and Methods of Drying

Liposomes freeze-drying method

Liquid pressure, drying methods

Mechanical Properties and Drying Methods

Metal different drying methods

Method for running a dry flash column

Modification Methods—Dry Processing

Pharmaceutical granulation drying methods

Plastic range, drying methods

Polymer composites freeze-drying method

Reaction methods drying tube method

Reaction methods drying tubes

SPECIALISED DRYING METHODS

Sample Preparation Using Dry Ashing Methods

Shrinkage drying methods

Size methods spray drying

Size methods spray-dried emulsions

Solvent drying methods

Specimen preparation method drying

Specimen preparation method drying methods

Specimen preparation method freeze drying

Spray drying method

Spray-drying, encapsulation method

Suitable drying methods

Water displacement drying method

Wet and dry methods

Wet versus dry methods

Wet/dry flow method

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