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Physical-biological processes

Azo Dye Wastewater Treatment Using Combined Physical-Biological Processes. .. 137... [Pg.133]

Weathering and transportation is followed by the sedimentation of material. The depositional environment can be defined as an area with a typical set of physical, chemical and biological processes which result in a specific type of rock. The characteristics of the resulting sediment package are dependent on the intensity and duration of these processes. The physical, chemical, biological and geomorphic variables... [Pg.78]

Microscopes are also used as analytical tools for strain analysis in materials science, detenuination of refractive indices and for monitoring biological processes in vivo on a microscopic scale etc. In this case resolution is not necessarily the only important issue rather it is the sensitivity allowing the physical quantity under investigation to be accurately detennined. [Pg.1655]

The primary types of conversion processes for biomass can be divided into four groups, ie, physical, biological—biochemical, thermal, and chemical. [Pg.16]

Movement of raw and transformed materials can take place within the soil and results in zones of accumulation, depletion, or mixing. Formation, migration, and accumulation of different elements, clays, oxides, and organic matter can occur in different parts of the soil. These different zones or layers in soil that are approximately parallel to the surface are called soil horizons. Depleted or enriched soil horizons result in different depths in the soil having different chemical and physical properties. Translocations are caused by a combination of physical, chemical, and biological processes. [Pg.169]

Box models and box-diffusion models have few degrees of freedom and they must describe physical, chemical, and biological processes very crudely. They are based on empirical relations rather than on first principles. Nevertheless, the simple models have been useful for obtaining some general features of the carbon cycle and retain some important roles in carbon cycle research (Craig and Holmen, 1995 Craig et al, 1997 Siegenthaler and joos, 1992). [Pg.303]

In addition to chemical reactions, the isokinetic relationship can be applied to various physical processes accompanied by enthalpy change. Correlations of this kind were found between enthalpies and entropies of solution (20, 83-92), vaporization (86, 91), sublimation (93, 94), desorption (95), and diffusion (96, 97) and between the two parameters characterizing the temperature dependence of thermochromic transitions (98). A kind of isokinetic relationship was claimed even for enthalpy and entropy of pure substances when relative values referred to those at 298° K are used (99). Enthalpies and entropies of intermolecular interaction were correlated for solutions, pure liquids, and crystals (6). Quite generally, for any temperature-dependent physical quantity, the activation parameters can be computed in a formal way, and correlations between them have been observed for dielectric absorption (100) and resistance of semiconductors (101-105) or fluidity (40, 106). On the other hand, the isokinetic relationship seems to hold in reactions of widely different kinds, starting from elementary processes in the gas phase (107) and including recombination reactions in the solid phase (108), polymerization reactions (109), and inorganic complex formation (110-112), up to such biochemical reactions as denaturation of proteins (113) and even such biological processes as hemolysis of erythrocytes (114). [Pg.418]

The environmental fate of chemicals is determined by both chemical/physical and biological processes in turn, the operation of these processes is dependent on the properties of the environmental chemicals themselves. Polarity, vapor pressure, partition coefficients, and chemical stability are all determinants of movement and... [Pg.72]

Basic biologic processes like photosynthesis and vision are fairly well understood. However, the perception of fight by individuals is not easy to describe in physical terms because the fight receptors differ considerably among species and... [Pg.5]

Many of the physical and chemical processes and phenomena that are basic to the vital fnnction of all biological systems are electrochemical in natnre. It is the primary task of bioelectrochemistry to reveal the mechanisms and basic electrochemical featnres of snch biological processes. [Pg.573]

Interfacial water molecules play important roles in many physical, chemical and biological processes. A molecular-level understanding of the structural arrangement of water molecules at electrode/electrolyte solution interfaces is one of the most important issues in electrochemistry. The presence of oriented water molecules, induced by interactions between water dipoles and electrode and by the strong electric field within the double layer has been proposed [39-41]. It has also been proposed that water molecules are present at electrode surfaces in the form of clusters [42, 43]. Despite the numerous studies on the structure of water at metal electrode surfaces using various techniques such as surface enhanced Raman spectroscopy [44, 45], surface infrared spectroscopy [46, 47[, surface enhanced infrared spectroscopy [7, 8] and X-ray diffraction [48, 49[, the exact nature of the structure of water at an electrode/solution interface is still not fully understood. [Pg.80]

Addressing the second question first leads to a critical constraint when thinking about new, more sustainable, technological developments, that is, the universal applicability of the laws of thermodynamics to aU physical, chemical and biological processes. A central and inescapable fact is the inevitability of waste formation. One statement of the second law of thermodynamics says that heat cannot be converted completely into work. Or, in other words, the energy output of work is always less than the energy transformed to accomplish it. A consequence of this is that, even in principle, it is impossible for any real process to proceed without the generation of some sort of waste. [Pg.7]


See other pages where Physical-biological processes is mentioned: [Pg.133]    [Pg.135]    [Pg.136]    [Pg.137]    [Pg.226]    [Pg.130]    [Pg.251]    [Pg.133]    [Pg.135]    [Pg.136]    [Pg.137]    [Pg.226]    [Pg.130]    [Pg.251]    [Pg.24]    [Pg.24]    [Pg.24]    [Pg.442]    [Pg.159]    [Pg.172]    [Pg.198]    [Pg.13]    [Pg.171]    [Pg.239]    [Pg.488]    [Pg.685]    [Pg.652]    [Pg.80]    [Pg.230]    [Pg.1]    [Pg.29]    [Pg.199]    [Pg.202]    [Pg.284]    [Pg.362]    [Pg.86]    [Pg.248]    [Pg.3]    [Pg.67]    [Pg.71]    [Pg.831]    [Pg.113]    [Pg.50]   
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