Universal method

In viscoelastic models in addition to the described conditions, stresses at the inlet should be given. As already mentioned there is no universal method to define such conditions, however, the following options may be considered (Tanner, 2000) ... 

There are many ways to classify a tank. Although there is no universal method, a classification commonly employed is based on the tank s internal pressure. 

The most universal method for sample destmction before SPh metal determination (Ee, Mo, A1 and etc.) is the sulfur acid digestion at high temperature by Kjeldall. It can be enforced by microwave decomposition in the microwave oven. 

Treatment of the solvent-free chromatogram with iodine vapor or by dipping in or spraying with iodine solution (0.5 — 1%) is a rapid and economical universal method of detecting lipophilic substances. Molecular iodine is enriched in the chromatogram zones and colors them brown. 

The most universal method for the synthesis of tantalum and niobium fluoride compounds is based on direct interaction between their pentafluorides, TaF5 or NbFs, and fluorides of other metals. Some physical-chemical properties of these compounds are presented in Table 8 [71, 72]. 

A very efficient and universal method has been developed for the production of optically pue L- and D-amino adds. The prindple is based on the enantioselective hydrolysis of D,L-amino add amides. The stable D,L-amino add amides are effidently prepared under mild reaction conditions starting from simple raw materials (Figure A8.2). Thus reaction of an aldehyde with hydrogen cyanide in ammonia (Strecker reaction) gives rise to the formation of the amino nitrile. The aminonitrile is converted in a high yield to the D,L-amino add amide under alkaline conditions in the presence of a catalytic amount of acetone. The resolution step is accomplished with permeabilised whole cells of Pseudomonas putida ATCC 12633. A nearly 100% stereoselectivity in hydrolysing only the L-amino add amide is combined with a very broad substrate spedfidty. 

Various in situ and ex situ methods have been used to determine the real surface area of solid electrodes. Each method10,15 32 67,73 74 218 is applicable to a limited number of electrochemical systems so that a universal method of surface area measurement is not available at present. On the other hand, a number of methods used in electrochemistry are not well founded from a physical point of view, and some of them are definitely questionable. In situ and ex situ methods used in electrochemistry have been recently reviewed by Trasatti and Petrii.73 A number of methods are listed in Table 3. 

Quantitative XRF analysis has developed from specific to universal methods. At the time of poor computational facilities, methods were limited to the determination of few elements in well-defined concentration ranges by statistical treatment of experimental data from reference material (linear or second order curves), or by compensation methods (dilution, internal standards, etc.). Later, semi-empirical influence coefficient methods were introduced. Universality came about by the development of fundamental parameter approaches for the correction of total matrix effects... 

CE determination of pKa is new, compared to the other techniques [144—147]. It has the advantage of being a rather universal method since different detection systems can be coupled to CE. Because it is a separation technique, sample impurities seldom are a problem. A fused-silica capillary, with an inner diameter of 50-75 pm and 27-70 cm in length is filled with a dilute aqueous buffer solution (ionic strength... 

Believe me, he wrote Machetanz, the university methods of ingesting knowledge into the student are somewhat different from little old Tarkio. They expect a man to absorb a whole science in one large gulp, and to get it down too. .. I have decided that I don t know any chemistry. ... 

Almost all target species that are monitored and controlled develop resistance to the pesticides used. As early as 1984, the US National Academy of Science gave an international conference on the issues of resistance it was admitted that, both in theory and practice, there are no satisfactory and universal methods of fighting pesticide resistance. The situation has not changed in the decades since. 

Methods for relating hardness values to other physical properties are presented, particularly chemical bond strengths. There is no universal method for doing this, although there have been attempts by other authors to do it with varying degrees of success. For example, see Gao, 2004. 

In summary, studies carried out with tissue surrogates25 highlight some of the problems that must be overcome before proteins extracted from FFPE tissues can be used for routine proteomic studies. First, these studies demonstrate that reversal of protein-formaldehyde adducts does not assure quantitative extraction of proteins from FFPE tissues or vice-versa. It may ultimately turn out that there is no one universal method that can accomplish both tasks, but that instead, each step will need to be optimized separately. Studies with tissue surrogates also suggest that failure to quantitatively extract the entire protein component from FFPE tissues may result in sampling bias due to the preferential extraction of certain proteins. This behavior may be linked to protein physical properties, such as the isoelectric point. The results of our... 

Unfortunately, there are no universal methods to detect all types of protein oxidation, because the products formed can be so diverse in nature. However, some forms of protein oxidation can be assayed using chemical modification (Davies et al., 1999 Shacter, 2000). In particular, the formation of carbonyl groups on proteins can be targeted using the reagent 2,4-dinitrophenyl-hydrazine (DNPH). This compound reacts with aldehydes to form 2,4-dinitrophenylhydrazone derivatives, which create chromogenic modifications that can be detected at high sensitivity in microplate assays or Western blot analysis (Buss et al., 1997 Winterbourn et al., 1999). 

Borylation of hydroxyalkylphosphines in the absence and presence of additional reagents is the most effective and universal method of synthesizing the boroxyalkyl derivatives of phosphorus, providing a wide variety of structures. Among other methods of synthesis of boroxyalkylphosphines from aminomethylphosphines is of special interest. This is illustrated in... 

Organometallic compounds vary widely in their properties and reactivity, just as do the elements from which they are produced. These compounds may be lithium alkyls, Grignard reagents, or organotin compounds. Accordingly, there is no universal method for preparing the compounds, but we will present here some of the types of reactions that have been widely employed. 

Selection of a flotation technique for gold preconcentration depends very much on the ore mineralogy, gangue composition and gold particle size. There is no universal method for flotation of the gold-bearing minerals, and the process is tailored to the ore characteristics. A specific reagent scheme and flowsheet are required for each ore. 

The surface area of PSs can be measured by means of quantitative electron microscopy (EM) [49-51], knowing the sizes of particles and pores [51,52], wetting heat [7,53] measurements, etc. But, the most universal methods are based on adsorption measurements [51,53-55], corresponding to the traditional methods of pore size distribution measurements in the range 0.3 to 100 nm. 

The way of the best choice to model PS s structure on both molecular and supramolecular levels begins with allocation of primary building units (PBUs), which without gaps and overlaps would fill a 3D space occupied by a PS. An universal method for allocation of such PBUs in both ordered and randomly arranged PSs, formed of packings of convex particles (or pores), is based on the construction of the assembles of Voronoi polyhedra (V-polyhedra) and Delaunay simplexes (or D-poly-hedra), which form Voronoi-Delaunay tessellation [100],... 

The chemical synthesis of oligosaccharides is also more complicated than the synthesis of other biopolymers, because the construction of each individual oligosaccharide poses a new challenge, requiring a knowledge of methods, together with experience and experimental skill. Thus, there are no universal methods available neither for biological in vivo nor for chemical in vitro syntheses. 

Chemical enrichment and class fractionation procedures vary from laboratory to laboratory. Thus, no universal method for further enrichment and fractionation exists. However, the following provides some specific examples of commonly used... 

Two methods, EPA SW-846 8015 and 8015A, were, in the past, often quoted as the source of gas chromatography-based methods for measurement of the total petroleum hydrocarbons in a sample. However, the original methods were developed for nonhalogenated volatile organic compounds and were designed to measure a short target list of chemical solvents rather than petroleum hydrocarbons. Thus, because there was no universal method for total petroleum hydrocarbons, there were many variations of these methods. Recently, an updated method... 

A universal method for carrying out redox processes between organic molecules, which has no parallel in thermal chemistry ... 

Purification of ionic liquids following single or multiple use. Side- or decomposition products of chemical reactions or catalysts will accumulate in the solvent. Cheap and reliable methods have to be developed for purification. Very probably there will not be a universal method. More likely for each type of process a specific method will be set up. 

Kacser H, Acerenza L. (1993) A universal method for achieving increases in metabolite production. Eur J Biochem 216 361-367. 

We have seen in previous sections that doping of insulahng hlms can be achieved through exposure to e.g., iodine gas. This practical and universal method can also be employed for the formahon of conducting layers on transparent and mechanically flexible polymeric substrates as discussed next. The example discussed here refers to conducting layers of 0-(BET-TTF)2Br-3H2O on a polycarbonate matrix (Mas-Torrent et al, 2001). 

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