Charging Characteristics

Stricter control of particle size distribution improves powder handling (qv) and transport through the system, and appHcation efficiency. It also reduces blinding of the final filter (69). Additives have been developed which improve the triboelectric charging characteristics (70). 

Depending on charge characteristics and storage history, charge resistance may be many times this value. 

Figure 8. Charge characteristics of an Ni-Cd battery at a constant current (cell type 1200SC temperature 20 °C).

Figure 21. General charging characteristics of an Ni-MH battery (cell type 4/3A).

Technologically it is important that smart battery packages, featuring power management by electronic devices within the battery package, are becoming a necessity due to the sensitive charging characteristics of Li and Ni-MeHy batteries, it should be noted that the same principles at a fraction of the cost have been successfully applied realized by simple reversal protection and overflow components by the low-cost RAM batteries. 

In soil, the chances that any enzyme will retain its activity are very slim indeed, because inactivation can occur by denaturation, microbial degradation, and sorption (61,62), although it is possible that sorption may protect an enzyme from microbial degradation or chemical hydrolysis and retain its activity. The nature of most enzymes, particularly size and charge characteristics, is such that they would have very low mobility in soils, so that if a secreted enzyme is to have any effect, it must operate close to the point of secretion and its substrate must be able to diffuse to the enzyme. Secretory acid phosphatase was found to be produced in response to P-deficiency stress by epidermal cells of the main tap roots of white lupin and in the cell walls and intercellular spaces of lateral roots (63). Such apoplastic phosphatase is safe from soil but can be effective only when presented with soluble organophosphates, which are often present in the soil. solution (64). However, because the phosphatase activity in the rhizo-sphere originates from a number of sources (65), mostly microbial, and is much higher in the rhizosphere than in bulk soil (66), it seems curious that plants would have a need to secrete phosphatase at all. 

Upon formation of a metal chelate or complex, the next rate-limiting step in delivering iron to the cell is the diffusion of iron complexes through the. soil in response to diffusion gradients. In the vicinity of plant roots, metal chelates and complexes may also move by bulk flow in the transpiration stream as water moves from the soil into the plant. However, depending on their charge characteristics and hydrophobicity, metal chelators and complexes can become adsorbed to clay and organic matter, which may then decrease their mobility and bioavail-... 

Soil-pH may influence both the concentrations of ions in the soil solution and the charge characteristics of the clay. Dispersion of clays is thus, to some extent, a pH-dependent process. At soil-pH(H2o,i i) values below 5, the aluminum concentration of the soil solution is normally sufficiently high to keep clay flocculated (Al3+ is preferentially adsorbed over divalent and monovalent ions in the soil solution). Between pH 5.5 and 7.0, the content of exchangeable aluminum is low . If concentrations of divalent ions are low, clay can disperse. At still higher pH values, divalent bases will normally keep the clay flocculated unless there is a strong dominance ofNa+-ions in the soil solution. 

Boyd SA, Jaynes WF (1994) Role of layer charge in organic contaminant sorption by organo-clays. In Mermut AR (ed) Layer charge characteristics of 2 1 silicate clay minerals. CMS Workshop Lecture Series, vol 6, The Clay Minerals Society, Boulder, CO, pp 48-77... 

Chloramines change LDL charge characteristics, inducing uncontrolled uptake of modified LDL by macrophages and the formation of cholesterol-engorged foam cells [160]. The ability of HOC1 to modify LDL was confirmed in a model system [161]. 

Isoelectric focusing also finds application in analysing the stability of biopharmaceuticals over the course of their shelf life. Repeat analysis of samples over time will detect deamidation or other degradative processes that alter protein charge characteristics. 

The adjuvanticity of liposomes depends upon their composition, number of layers and charge characteristics. They act as effective adjuvants for both protein- and carbohydrate-based antigens and help stimulate both B- and T-cell responses. Their likely mode of action includes depot formation, but they also possibly increase/enhance antigen presentation to macrophages. The exact molecular mechanism(s) by which they stimulate a T-cell response remains to be elucidated,... 

Whereas lipoplexes/polyplexes generally protect the plasmid from serum nucleases, the overall positive charge characteristic of these structures leads to their non-specific interactions with cells... 

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