Organic complexation

Vanadium is found in about 65 different minerals among which are carnotite, roscoelite, vanadinite, and patronite, important sources of the metal. Vanadium is also found in phosphate rock and certain iron ores, and is present in some crude oils in the form of organic complexes. It is also found in small percentages in meteorites. 

In this experiment the method of continuous variations is used to determine the stoichiometry and equilibrium constant for the organic complex of 3-aminopyridine with picric acid in CHCI3, and the inorganic complex of Fe +with salicylic acid. 

Synthetic organic chelates and natural organic complexes are sometimes more effective agronomically per unit of micronuttient than inorganic forms, but the organic materials are more expensive. The chelates can be used with both orthophosphate and polyphosphate Hquids and suspensions. 

Stripping is accompHshed by dehydration using sulfuric acid (38), lithium chloride [7447-41-8] (39), and tertiary amines containing from 14—32 carbon atoms in an organic solvent immiscible with water followed by thermal treatment of the HCl—organic complex (40). 

Explosives. Mercury, in the form of organic complexes, eg, mercury fulminate [628-86-4] has had long usage in explosives (see Explosives and propellants). In the United States all mercury for use in explosives is diverted to military uses. An explosive based on mercuric 5-nitrotetra2ole [60345-95-1] has been developed, but its use is on a small scale and in research and development only (3). 

Chromium. The history of the investigations estabHshing the essentiaHty of chromium has been reviewed (136). An effect of brewer s yeast in preventing or curing impaired glucose tolerance in rats was revealed, and the active factor was identified as a Cr(III) organic complex, glucose tolerance... 

Bonding Agents. These materials are generally only used in wire cable coat compounds. They are basically organic complexes of cobalt and cobalt—boron. In wire coat compounds they are used at very low levels of active cobalt to aid in the copper sulfide complex formation that is the primary adherance stmcture. The copper sulfide stmcture builds up at the brass mbber interface through copper in the brass and sulfur from the compound. The dendrites of copper sulfide formed entrap the polymer chains before the compound is vulcanized thus hoi ding the mbber firmly to the wire. 

Chemical Variety. The term species refers to the actual form in which a molecule or ion is present in solution. Eor example, a metal ion may occur in natural waters, as a free metal ion, ie, an aquo complex Me(H20), an inorganic or organic complex, and it may be present in dissolved or... 

Heavy Metals. Heavy metals of particular concern in the treatment of wastewaters include copper, chromium, 2inc, cadmium, mercury, lead, and nickel. They are usually present in the form of organic complexes, especially in wastewaters generated from textiles finishing and dye chemicals manufacture. 

Generally, most asphalts are 79—88 wt % C, 7—13 wt % H, trace-8 wt % S, 2—8 wt % O, and trace-3 wt % N (Table 7). Trace metals such as iron, nickel, vanadium, calcium, titanium, magnesium, sodium, cobalt, copper, tin, and 2inc, occur in cmde oils. Vanadium and nickel are bound in organic complexes and, by virtue of the concentration (distillation) process by which asphalt is manufactured, are also found in asphalt. 

Fillers can also be used to promote or enhance the thermal stability of the silicone adhesive. Normal silicone systems can withstand exposure to temperatures of 200 C for long hours without degradation. However, in some applications the silicone must withstand exposure to temperatures of 280 C. This can be achieved by adding thermal stabilizers to the adhesive formulations. These are mainly composed of metal oxides such as iron oxide and cerium oxide, copper organic complexes, or carbon black. The mechanisms by which the thermal stabilization occurs are discussed in terms of radical chemistry. 

EINSTein (Enhanced ISAAC Neural Simulation Toolkit), was developed to address the basic question To what extent is land combat a self-organized complex... 

Fluorimetry is generally used if there is no colorimetric method sufficiently sensitive or selective for the substance to be determined. In inorganic analysis the most frequent applications are for the determination of metal ions as fluorescent organic complexes. Many of the complexes of oxine fluoresce strongly aluminium, zinc, magnesium, and gallium are sometimes determined at low concentrations by this method. Aluminium forms fluorescent complexes with the dyestuff eriochrome blue black RC (pontachrome blue black R), whilst beryllium forms a fluorescent complex with quinizarin. 

Specificity for alkali and alkaline earth cations of synthetic and natural organic complexing agents in membranes. W. Simon, W. E. Morf and P. C. Meier, Struct. Bonding (Berlin), 1973, 16, 113-160 (123). 

Kj is the distribution ratio of uncomplexed ions and all low molecular weight inorganic and organic complexes (ultrafiltration cutoff was at a molecular weight of 1000). 

The K1/K3 ratios divide these natural waters into three groups. Okeefenokee Swamp and Volo Bog have ratios of about 3 a group of small lakes and two coastal marine waters show a somewhat weaker binding with K1/K3 ranging from 0.16 to 0.56 Lake Michigan exhibits much weaker organic complexes with a K]VK3 of 0.03. 

Mathew and Pillai observed a threefold increase in plutonium concentration at low, normal, and high carbonate concentrations when 20mg/liter of organic matter were added to sea water samples (29). Again this indicates the effect of organic complexation upon plutonium solubility in natural waters. 

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