Constituents, consistency

Nucleoside (Section 28.1) A nucleic add constituent, consisting of a sugar residue bonded to a heterocyclic purine or pyrimidine base. 

ABSTRACT Panax ginseng is one of the most investigated medicinal plants. In the Eastern world it has been used for more than 2000 years as a tonic and prophylactic to increase nonspecific resistance against a variety of stress agents. The plant contains more than 200 identified chemical compounds and among them the ginsenosides are considered the most important constituents. Consistent efficacy and safety require constantly uniform composition, a condition which the raw material (roots) can scarcely fulfill. 

T HE PRESENCE OF ORGANIC CONSTITUENTS IN DRINKING WATER has been known for many years because these substances were found to influence the taste, color, and odor of drinking waters (J). The organic constituents consist of compounds of both natural and industrial origin. The natural ones compose the major portion and include mainly undefined fulvic and humic acids (2). For the industrial ones, most attention has been paid so far to the volatile nonpolar compounds. In part, this situation is due to analytical (technical) restrictions and to the growing awareness (3, 4) that volatile halogenated hydrocarbons are introduced as a result of a chlorine treatment. 

Saturated constituents contribute less to the vacuum gas oil than the aromatics but more than the polar constituents that are now present at percentage rather than trace levels. The vacuum gas oil itself is occasionally used as heating oil but most commonly it is processed by catalytic cracking to produce naphtha or by extraction to yield lubricating oil. Within the vacuum gas oil saturates, the distribution of paraffins, /iso-paraffins and naphthenes is highly dependent upon the petroleum source. The bulk of the vacuum gas oil saturated constituents consist of /Iso-paraffins and naphthenes. The naphthenes contain from one to more than six fused rings and have alkyl substituents. For mono- and di-aromatics, the alkyl substitution typically involves one long side chain and several short methyl and ethyl substituents. 

Not all the major constituents consistently exhibit conservative behaviour in the ocean. The most notable departures occur in deepwaters, where Ca and HCO3 exhibit anomalously high concentrations due to the dissolution of calcite. The concept of relative constant composition does not apply in a number of atypical environments associated with boundary regions. Inter-element ratios for major constituents can be quite different in estuaries and near hydrothermal vents. Obviously, these are not solutions of sea salt with the implication that accuracy of salinity measurements by chemical and conductometric means is limited. 

Pectin is a high-molecular-weight, carbohydrate-like plant constituent consisting primarily of chains of galacturonic acid units linked as 1,4-a-glucosides, with a molecular weight of 30 000-100000. 

The volatile constituents of Conyza dioscorides L. (Desf.) growing in Egypt showed promising antimicrobial activities against some tested microorganisms [153]. The volatile constituents consisted mainly of sesquiterpene hydrocarbons and oxygenated sesquiterpenes. The major sesquiterpene hydrocarbons are (3-maaliene and a-elemene, while the major oxygenated sesquiterpene compounds are a-cadinol, muurolol, caryophyllene oxide isomers and a sesquiterpene alcohol. 

The fine flavor and bouquet result from the secondary constituents of the brandy and are dependent upon a number of factors, principally raw materials, operating methods, aging, etc. The secondary constituents consist of various esters (acetic, butyric, oenanthic, valerianic), acetic acid, volatile oils, tannin, fixed acid and coloring matter. Ethyl pelargonate (oenanthic ester) and other volatile constituents are thought to be mainly responsible for the flavor. 

Biopolymers are the type of polymer whose basic constituents consist mainly of renewable resources. These basic constituents can be formed either from the polymer chain or side chain, or from the monomers which are to be cross-linked to the polymers. A number of formation possibilities for biopolymers can be created as result. 

Heterogeneous Comprised of different elements or constituents, consisting of more than one phase, properties vary from point to point. 

Fig. 5. A hypothetical training set of spectra with three independent constituents consisting of two Gaussian bands each.

Analyser systems are available commercially but may also be constructed from single components according to individual requirements. A typical system for the automated analysis of seawater constituents consists of a sampler, proportioning pump, the analytical manifold (a delay and reaction system), a flow-through spectrophotometer and a data acquisition system. Fig. 10-13 shows a 4-channel CFA system built and used in the Institute of Marine Research in Kiel (Germany). One example manifold (nitrate) including a flow-through-spectrophotometer is displayed in Fig.10-14. 

The chemical reactions of the RRS processes are complex, and a large number of products are present in the neutralent waste streams. However, all four processes effectively destroy the chemical agents and produce waste streams that could be shipped to hazardous waste incinerators. The compositions of the neutralent waste streams are shown in Table 2-2. The dominant constituents consist of the reaction solvents and excess DCDMH. A large number of reaction by-products (e.g., sulfones, sulfoxides, etc.) are present in low concentrations. 

This sample, as will be observed, contained practically no geraniol, the alcoholic constituents consisting entirely of citronellol. 

For many industrial applications (e.g., pharmaceutical pills), where particles often differ in both size and density, the degree to which a particle system is well mixed can determine the quality of a final product. In these cases, the search for a crossover point where density and size segregation effects balance one another is compelling. Efforts have typically focused on combinations of relative size and density in a mixture of particles that are smaller and less dense compared with another constituent consisting of particles that are larger and denser. 

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