Composition physicochemical properties

Serra Bonvehi, J., Gomez-Pajuelo, A., and Gonell-Galindo, F. (1987). Composition, physicochemical properties and pollen spectrum of various single-flower honeys from Spain. 

To induce this reaction, the kinetic inhibition of the reaction must be overcome by applying an overpotential, which must be minimized. This reaction, in which electrons are transferred across the metal-solution interface with a resulting nitrate reduction, is called a faradaic process. Also, the complexity of the interfacial system is such that other phenomena do occur that can affect the electrode behavior. These processes include adsorption, desorption, and charging of the interface as a result of changing electrode potential these are called non-faradaic processes. Both the efficiency and the selectivity of nitrate electroreduction strongly depend on several parameters such as the electrode composition, physicochemical properties of the electrolyte (pH, coexisting species, temperature, etc.) and the applied potential. 

Lawal OS. Composition, physicochemical properties and retrogradation characteristics of native, oxidised, acetylated and acid-thinned new cocoyam (Xanthosoma sagittifo-lium) starch. Food Chem 2004 87 205-218. 

Tan, T.-C., Cheng, L.-H., Bhat, R., Rusul, G., Easa, A. M. (2014). Composition, physicochemical properties and thermal inactivation kinetics of polyphenol oxidase and peroxidase from coconut (Cocos nucifera) water obtained from immature, mature and overly-mature coconut. Food Chemistry, 142(0), 121-128. doi http //dx.doi.org/10.1016/ j.foodchem.2013.07.040... 

A review of the composition, physicochemical properties and biological behaviour of the principal types of bioceramics is given, based on the literature and some of our own data. The materials include, in addition to bioceramics, bioglasses and bio-glass-ceramics. Special attention is given to structure as the main physical parameter determining nor only the properties of the materials, but also their reaction with the surrounding tissue. 

The two pigments, hemerythrin and hemocyanin, will be discussed separately in this chapter. The following subjects will be considered in both cases distribution, preparation, chemical composition, physicochemical properties, and functional structure. 

A colloid is a material that exists ia a finely dispersed state. It is usually a solid particle, but it may be a Hquid droplet or a gas bubble. Typically, coUoids have high surface-area-to-volume ratios, characteristic of matter ia the submicrometer-size range. Matter of this size, from approximately 100 nm to 5 nm, just above atomic dimensions, exhibits physicochemical properties that differ from those of both the constituent atoms or molecules and the macroscopic material. The differences ia composition, stmcture, and iateractions between the surface atoms or molecules and those on the iaterior of the colloidal particle lead to the unique character of finely divided material, specifics of which can be quite diverse (see Flocculating agents). 

Detergent compositions also vary from country to country. The world market for household detergents can be divided into four segments according to the physicochemical properties of the wash solutions prepared from the detergents. 

Physicochemical properties of molten systems have an applied significance due to their wide use in both technological process planning and in production equipment design. Analysis of various melt properties versus different parameters of the melt enables to infer the interaction mechanism between the initial components, and in some cases, even to estimate the possible composition of the main complex ions formed in the melt [312]. From this point of view, the analysis of isotherms of physicochemical properties versus melt composition and of the magnitude of their deviation from ideal conditions is of most interest. 

Composite structures that consist of carbon particles and a polymer or plastic material are useful for bipolar separators or electrode substrates in aqueous batteries. These structures must be impermeable to the electrolyte and electrochemical reactants or products. Furthermore, they must have acceptable electronic conductivity and mechanical properties. The physicochemical properties of carbon blacks, which are commonly used, have a major effect on the desirable properties of the conductive composite structures. Physicochemical properties such as the surface... 

The physicochemical properties of carbon are highly dependent on its surface structure and chemical composition [66—68], The type and content of surface species, particle shape and size, pore-size distribution, BET surface area and pore-opening are of critical importance in the use of carbons as anode material. These properties have a major influence on (9IR, reversible capacity <2R, and the rate capability and safety of the battery. The surface chemical composition depends on the raw materials (carbon precursors), the production process, and the history of the carbon. Surface groups containing H, O, S, N, P, halogens, and other elements have been identified on carbon blacks [66, 67]. There is also ash on the surface of carbon and this typically contains Ca, Si, Fe, Al, and V. Ash and acidic oxides enhance the adsorption of the more polar compounds and electrolytes [66]. 

The present study is devoted to the examination of the structure of this boundary layer, which is called mesophase, and which is created between phases in the composite, mainly on the side of the softer phase. This new infinitesimal phase may be assumed as constituting an independent phase, lying between the two principal phases, with its own particular mechanical and physicochemical properties. 

The composition of AOS and IOS is determined by the choice of the olefin feedstock, by the way the feedstock is sulfonated and by manufacturing conditions. As will be shown later, the structural parameters such as hydrophobe chain length and branching, the ratio of alkene- to hydroxyalkanesulfonate, and (for AOS) the mono disulfonate ratio determine the physicochemical properties of AOS and IOS these in turn determine the performance of AOS and IOS in their end formulations. 

In 1868 two Scottish scientists, Crum Brown and Fraser [4] recognized that a relation exists between the physiological action of a substance and its chemical composition and constitution. That recognition was in effect the birth of the science that has come to be known as quantitative structure-activity relationship (QSAR) studies a QSAR is a mathematical equation that relates a biological or other property to structural and/or physicochemical properties of a series of (usually) related compounds. Shortly afterwards, Richardson [5] showed that the narcotic effect of primary aliphatic alcohols varied with their molecular weight, and in 1893 Richet [6] observed that the toxicities of a variety of simple polar chemicals such as alcohols, ethers, and ketones were inversely correlated with their aqueous solubilities. Probably the best known of the very early work in the field was that of Overton [7] and Meyer [8], who found that the narcotic effect of simple chemicals increased with their oil-water partition coefficient and postulated that this reflected the partitioning of a chemical between the aqueous exobiophase and a lipophilic receptor. This, as it turned out, was most prescient, for about 70% of published QSARs contain a term relating to partition coefficient [9]. 

Electrolytes are highly important components of all galvanic cells and electrochemical devices. In most electrochemical devices, such as electrolyzers, batteries, and the like, aqueous solutions of acids and salts are used as electrolytes. Aqueous solutions are easy to prepare, convenient to handle, and as a rule are made from readily available, relatively inexpensive materials. By changing the composition and concentration of the components, it is relatively easy to adjust the specific conductance and other physicochemical properties of these aqueous solutions. 

The corrosion resistance of lithium electrodes in contact with aprotic organic solvents is due to a particular protective film forming on the electrode surface when it first comes in contact witfi tfie solvent, preventing further interaction of the metal with the solvent. This film thus leads to a certain passivation of lithium, which, however, has the special feature of being efiective only while no current passes through the external circuit. The passive film does not prevent any of the current flow associated with the basic current-generating electrode reaction. The film contains insoluble lithium compounds (oxide, chloride) and products of solvent degradation. Its detailed chemical composition and physicochemical properties depend on the composition of the electrolyte solution and on the various impurity levels in this solution. 

In order to answer questions regarding the therapeutic and cosmetic uses of the myriad dermatological concoctions available, a pharmacist must be knowledgeable about the anatomical structure and physiological functions of the skin and the chemical compositions and physicochemical properties of its constituent tissues. Some understanding of how its properties are affected by disease and damage is a must, as is... 

Table 11 Physicochemical Properties and Composition of Human Lipoproteins... 

Orally administered dosage forms are absorbed into the systemic circulation following dissolution in the GI tract. Because substances must be in solution for the absorption from the GI lumen, the absorption rate of poorly water-soluble drugs is limited by their rate of dissolution. The dissolution rate is affected by the unique physicochemical properties of the drug and by physiological factors the pH, composition, and hydrodynamics of the GI medium. 

Despite the diversity of analytical procedures, no valid selection of solely right methods exists. Depending on the problem, the nature of the free radicals themselves or the physicochemical properties of the test system such as composition and hydrophobicity of the medium, oxygen partial pressure, pH value, etc., are important as well [15-17], An adequate test system is characterized by the fact that with regard to size, lipophilicity, and reactivity the biological target substrate reacts with the most relevant radicals. 

The present research was conducted to evaluate selected physicochemical properties of the dry roasted and air-classified navy, pinto, and black bean flour fractions. Studies were conducted to determine the chemical composition and to characterize the functional properties of dry-roasted bean flour fractions and to evaluate the suitability of the flours for use in foods systems. 

The fate of surfactants (Fig. 1.17) in wastewater treatment plants (WWTP) is determined by, among other factors, the composition of the wastewater, the operational type of the WWTP and the physicochemical properties of the surfactant molecule itself. In general, WWTPs provide a primary treatment, which is simply the removal of solid materials by mechanical means. 

The process of combining cyanine and squaraine dyes by encapsulation, or covalent or noncovalent attachment with macrocyclic hosts, macromolecules, and micro- or nano-particles is a promising way to design novel probes and labels with substantially improved properties and for the development of advanced fluorescence-based assays. Nevertheless, the physicochemical properties of these dye-compositions are strongly dependent on the dye structure as well as the nature of the host macrocycle, macromolecule, or particle. Finally, development of new methods to synthesize these tracers can also be considered a challenging task. 

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