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Heavy metals function

It is thought that the function of the glue or gelatin is to combine with very slight traces of heavy metal cations, for example Cu, which are known to catalyse the nitrogen-forming reaction. [Pg.220]

In general, nonconventional protein foods must be competitive with conventional plant and animal protein sources on the bases of cost delivered to the consumer, nutritional value to humans or animals, functional value in foods, sensory quality, and social and cultural acceptability. Also, requirements of regulatory agencies in different countries for freedom from toxins or toxic residues in single-cell protein products, toxic glycosides in leaf protein products, pathogenic microorganisms, heavy metals and toxins in fish protein concentrates, or inhibitory or toxic peptide components in synthetic peptides must be met before new nonconventional food or feed protein products can be marketed. [Pg.472]

Chemical precipitation can remove 95 percent of the suspended solids, up to 50 percent of the soluble organics and the bulk of the heavy metals in a wastewater. Removal of soluble organics is a function of the coagulant chemical, with iron salts yielding best results and lime the poorest. Metal removal is primarily a function of pH and the ionic state of the metal. Guidance is available from solubihty product data. [Pg.2215]

Heavy metals Cation Polystyrene matrix Chelating functional groups Mineral acids... [Pg.2227]

BBT solution on unmodified sorbents of different nature was studied. Silica gel Merck 60 (SG) was chosen for further investigations. BBT immobilization on SG was realized by adsoi ption from chloroform-hexane solution (1 10) in batch mode. The isotherm of BBT adsoi ption can be referred to H3-type. Interaction of Co(II), Cu(II), Cd(II), Ni(II), Zn(II) ions with immobilized BBT has been studied in batch mode as a function of pH of solution, time of phase contact and concentration of metals in solution. In the presence of sodium citrate absorbance (at X = 620 nm) of immobilized BBT grows with the increase of Cd(II) concentration in solution. No interference was observed from Zn(II), Pb(II), Cu(II), Ni(II), Co(II) and macrocomponents of natural waters. This was assumed as a basis of soi ption-spectroscopic and visual test determination of Cd(II). Heavy metals eluted from BBT-SG easily and quantitatively with a small volume of HNO -ethanol mixture. This became a basis of soi ption-atomic-absoi ption determination of the total concentration of heavy metals in natural objects. [Pg.292]

The function of pH adjustment is to neutralize acids and bases and to promote the formation of precipitates (especially of heavy metal precipitates) which can subsequently be removed by conventional settling techniques. These purposes are not mutually exclusive, precipitates can be formed as the result of neutralizing a waste. Conversely, neutralization of the waste stream can result when adjusting the pH to effect chemical precipitation. Typically, pH adjustment is effective in treating inorganic or... [Pg.144]

Mean arterial pressure and cardiac output, an expression of the amount of blood that the heart pumps each minute, are the key Indicators of the normal functioning of the cardiovascular system. Mean arterial pressure is strictly controlled, but by changing the cardiac output, a person can adapt, e.g., to increased oxygen requirement due to increased workload. Blood flow in vital organs may vary for many reasons, but is usually due to decreased cardiac output. However, there can be very dramatic changes in blood pressure, e.g., blood pressure plummets during an anaphylactic allergic reaction. Also cytotoxic chemicals, such as heavy metals, may decrease the blood pressure. [Pg.297]

Therapeutic Function Antidote in heavy metal poisoning Chemical Name N-(2-Mercapto-1-oxopropyl)glycine Common Name Mercamidum... [Pg.1496]

Grill, E., Winnacker, E.-L. Zenk, M.H. (1987). Phytochelatins, a class of heavy-metal-binding peptides from plants, are functionally analogous to metallo-thioneins. Proceedings of the National Academy of Sciences, USA, 84, 439-43. [Pg.176]

Interactions studies between some divalents metal ions and pectins from citms and sugar-beet revealed that the chemical structure of the latter, namely the presence of acetyl functions, induces differences of binding process whereas the scale of selectivity was not affected. Some further studies could be carried out on the correlation between the binding mode and the degree of acetylation. Lastly, pectins showed a clear scale of selectivity towards heavy metals with high capacities of binding which make them suitable to be used in waste-waters depollution. [Pg.539]

Among potentiometric methods of analysis that are important for ecological applications, the one most widely used is that of pH measurements with an indicator electrode whose potential is a function of the hydrogen ion concentration. More recently, ion-selective electrodes reversible to other cations such as those of heavy metals have become available. [Pg.407]

C. Leyval, K. Turnau, and K. Haselwandter, Effect of heavy metal pollution on mycorrhizal colonization and function physiological, ecological and applied aspects. Mycorrhiza 7 139 (1997). [Pg.294]

Ziegler, T., 1995, Density Functional Theory as a Practical Tool in Studies of Organometallic Energetics and Kinetics. Beating the Heavy Metal Blues With DFT , Can. J. Chem., 73, 743. [Pg.306]


See other pages where Heavy metals function is mentioned: [Pg.244]    [Pg.92]    [Pg.244]    [Pg.92]    [Pg.487]    [Pg.336]    [Pg.438]    [Pg.259]    [Pg.528]    [Pg.297]    [Pg.2209]    [Pg.2216]    [Pg.2227]    [Pg.440]    [Pg.35]    [Pg.38]    [Pg.38]    [Pg.43]    [Pg.377]    [Pg.90]    [Pg.396]    [Pg.302]    [Pg.396]    [Pg.498]    [Pg.214]    [Pg.257]    [Pg.23]    [Pg.448]    [Pg.174]    [Pg.22]    [Pg.374]    [Pg.38]    [Pg.223]    [Pg.253]    [Pg.264]    [Pg.196]    [Pg.265]    [Pg.200]    [Pg.724]    [Pg.725]   
See also in sourсe #XX -- [ Pg.95 , Pg.97 ]




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