Oxidative source

If the mean urine pH of cats fed ad libitum is not below 6.4, the risk of stmvite uroHthiasis iucreases as the magnesium content of the diet iucreases. Because of very poor bioavailabiUty, iron from carbonate or oxide sources that are added to the diet should not be considered as components ia meeting the minimum nutrient level ia cats. 

The choice of selected raw materials is very wide, but they must provide calcium oxide (lime), iron oxide [1309-37-1/, siHca, and aluminum oxide (alumina). Examples of the calcereous (calcium oxide) sources are calcium carbonate minerals (aragonite [14791-73-2] calcite [13397-26-7] limestone [1317-65-3] or mad), seasheUs, or shale. Examples of argillaceous (siHca and alumina) sources are clays, fly ash, mad, shale, and sand. The iron oxide commonly comes from iron ore, clays, or mill scale. Some raw matedals supply more than one ingredient, and the mixture of raw matedals is a function of their chemical composition, as deterrnined by cost and availabiHty. 

Detonation arresters are typically used in conjunction with other measures to decrease the risk of flame propagation. For example, in vapor control systems, the vapor is often enriched, diluted, or inerted, with appropriate instrumentation and control (see Effluent Disposal Systems, 1993). In cases where ignition sources are present or pre-dic table (such as most vapor destruct systems), the detonation arrester is used as a last-resort method anticipating possible failure of vapor composition control. Where vent collec tion systems have several vapor/oxidant sources, stream compositions can be highly variable and... 

Natural gas will continue to be substituted for oil and coal as primary energy source in order to reduce emissions of noxious combustion products particulates (soot), unburned hydrocarbons, dioxins, sulfur and nitrogen oxides (sources of acid rain and snow), and toxic carbon monoxide, as well as carbon dioxide, which is believed to be the chief greenhouse gas responsible for global warming. Policy implemented to curtail carbon emissions based on the perceived threat could dramatically accelerate the switch to natural gas. 

Nickel is a malleable, ductile, tenacious, slightly magnetic, silvery white metal, which conducts heat and electricity fairly well. It is ferromagnetic at ordinary temperatures but becomes paramagnetic at elevated temperatures. Nickel is closely related in chemical properties to iron and cobalt. While sulphidic sources of nickel account for the world s major nickel supplies, it may be pointed out that lateritic nickel deposits (which essentially constitute an oxidic source of the metal) are more extensive than the sulphidic sources. 

Minerals belonging to the category of insoluble oxide and silicate minerals are many in number. Insoluble oxide minerals include those superficially oxidized and those of oxide type. The former category comprises mainly superficially oxidized sulfide minerals, including metals such as aluminum, tin, manganese, and iron which are won from their oxidic sources. As far as silicate minerals are concerned, there can be a ready reference to several metals such as beryllium, lithium, titanium, zirconium, and niobium which are known for their occurrence as (or are associated with) complex silicates in relatively low-grade deposits. 

The reduction smelting process involves the reduction of oxidic sources of metals with carbon in the presence of a flux. The process can generally be represented as ... 

Oxidant Sources of oxygen for chemical oxidations Active oxygen Co-product... 

Friction factors for turbulent flow of dilute solutions of polyethylene oxide Source R. W. Patterson and F. H. Abernathy, Journal of Fluid Mechanics, 51, pp. 177-85(1972)... 

When a spadeful of wet, anaerobic soil is brought to the surface and allowed to dry, air enters through drying cracks and the soil tends to become uniformly oxidized and turn a uniform brown. Whereas when oxidation occurs without drying—as, for example, near a root releasing O2 into wet soil—it is far less uniform and reddish-brown ferric oxide deposits form on and near the oxidizing source. The difference depends on the relative rates of movement of O2 into the soil and of ferrous iron and other reductants in the opposite direction, and the rates of reaction. 

In the chemiluminescent detection of nitrogen oxides, a constant source of ozone reacts with a metered air sample containing nitric oxide. Fontijn et al. suggested that this method could also be used for ozone detection by using a constant nitric oxide source for reaction with ozone in the air sample. The ozone-nitric oxide reaction is carried out at reduced pressure, to avoid quenching the chemiluminescent reaction. Detection of the emission in the spectral r on involved (600-3,000 nm) requires using a near-infrared-sensitive photomultiplier tube. The noise of such a photomultiplier tube is reduced by cooling it to about - 20 C. ... 

FIGURE 14-1 The tropospheric ozone cycle. Reprinted with permission from Corn er al.. Photochemical oxidants Sources, sinks and strategies, J. Air Pbllut. Control Assoc. 25 16-18, 1975. 

Ganske, J. A., H. N. Berko, and B. J. Finlayson-Pitts, Absorption Cross Sections for Gaseous C1N02 and Cl2 at 298 K Potential Organic Oxidant Source in the Marine Troposphere, J. Geophys. Res., 97, 7651-7656 (1992). 

Procedure. In preparation for a series of experimental runs, the top and bottom sections of the furnace were brought to their proper operating temperatures, the air flow was started, and a standby source of radioactive oxide vapor was inserted into the lower section of the furnace. After about a 24-hour equilibration period, the standby oxide source was replaced with the regular source which had just been weighed. 

Here we consider carbon monoxide as a chemical reducing agent, with the oxidation product being C02 in all cases. Carbon monoxide may act as a reductant in three different ways (1) as a direct oxygen atom acceptor (2) as a two-electron reductant with water as the source of oxygen and (3) as an indirect reductant in which the reducing power of CO is used to make H2 which then carries out the desired reduction. The three ways are shown schematically as (24)-(26) (in (24) [O] represents an oxide source). Equation... 

Figure 11 Part of a static micromixer manufactured by laser ablation from aluminum oxide. (Source Ehrfeld Mikrotechnik, Heidelberg Instruments Microtechnologies.)...

Usually, racemerisation of semi-acetal such as 30 is possible. This circumstance is not important in this case since lactole 30 is immediately oxidized to lactone 10. Iodine is the oxidizing source and CaC03 traps resulting HI. 

The subject is highly relevant in the search for more effective, safe and economical activation methods, employing hydrogen peroxide as the primary oxidant source. 

Of course, once the ore is obtained from its deposit, the actual work of extracting the desired metal has yet to be accomplished. In addition to metals, a variety of other substances comprise natural minerals. Since aluminum and silicon are the most prevalent elements in the Earth s crust, most of the metals exist naturally as aluminates, silicates, or aluminosilicates. The most common minerals are feldspars and clays. These materials have been used since ancient times for the production of materials such as pottery, brick, and china. An example of a feldspar is K2Al2Si60i6, which corresponds to a mixture of potassium superoxide, alumina, and silica (K20-Al203 6Si02). Upon contact with water and carbon dioxide, a weathering reaction results in kaolinite, an aluminosilicate clay (Eq. 1). However, in addition to these oxidized sources of metals, there are substances such as alkaline carbonates, sulfates, phosphates, as well as organic matter that need to be removed to yield the desired metal. As you would expect, the yield for this process is quite low ores typically possess less than 1 % of the desired metal ... 

Nevison, C., Lueker, T., and Weiss, R. F. (2004). Quantifying the nitrous oxide source from coastal upweUing. Global Biogeochem. Cycles 18, GB1018, doi 10.1029/2003GB002110. 

The initial tests of the model (DIFKIN) combining diffusion with kinetics were conducted for the Type 3 day. The rate ratio and NO. source strength ratio hypotheses were tested, as shown in Figures 27, 28, and 29. The first set of graphs illustrates most clearly the need for a downward adjustment in the nitric oxide source strength (or flux). Consistent with the results of References 85 and 87, Figures 24, 25, and 26... 

By shift from a reactive solvent (e.g., water) to an inert solvent (e.g., acetonitrile), this problem can be easily solved. Acetonitrile is oxidized just outside the potential window of the band gap of common semiconductors, so the adsorbed substrate can be selectively oxidized. Without an oxidative source for producing hydroxyl radicals, however, there are fewer opportunities for the incorporation of OH groups. 

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