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Phosphomics

The section on Spectroscopy has been retained but with some revisions and expansion. The section includes ultraviolet-visible spectroscopy, fluorescence, infrared and Raman spectroscopy, and X-ray spectrometry. Detection limits are listed for the elements when using flame emission, flame atomic absorption, electrothermal atomic absorption, argon induction coupled plasma, and flame atomic fluorescence. Nuclear magnetic resonance embraces tables for the nuclear properties of the elements, proton chemical shifts and coupling constants, and similar material for carbon-13, boron-11, nitrogen-15, fluorine-19, silicon-19, and phosphoms-31. [Pg.1284]

Semiconductors may also be made from a maferial which is normally an insulator by infroducing an impurify, a process known as doping. Figure 9.9 shows fwo ways in which an impurify may promote semiconducting properties. In Figure 9.9(a) fhe dopanf has one more valence election per atom fhan fhe hosf and confribufes a band of filled impurify levels 1 close to fhe conduction band of fhe hosf. This characterizes an n-fype semiconductor. An example is silicon (KL3s 3p ) doped wifh phosphoms (KL3s 3p ), which reduces fhe band gap to abouf 0.05 eY Since kT af room femperafure is abouf 0.025 eY the phosphoms... [Pg.350]

Biocides should not be present in water used for aquaculture. Sources of herbicides and pesticides are mnoff from agricultural land, contamination of the water table, and spray drift from crop-dusting activity. Excessive levels of phosphoms and nitrogen may occur where mnoff from fertilized land enters an aquaculture faciUty either from surface mnoff or groundwater contamination. Trace metal levels should be low as indicated in Tables 4 and 5. [Pg.20]

Bloremedia.tlon. Cmde oil and refined products are readily biodegradable under aerobic conditions, but they are only incomplete foods siace they lack any significant nitrogen, phosphoms, and essential trace elements. Bioremediation strategies for removing large quantities of hydrocarbon must therefore iaclude the addition of fertilisers to provide these elements la a bioavailable form. [Pg.29]

Compounds with organophosphate moieties, such as Diazinon, Methyl Parathion, Coumaphos and Glyphosate are usually hydrolyzed at the phosphoms atom (40,58). Indeed several Flavobacterium isolates are able to grow using parathion and diazinon as sole sources of carbon. [Pg.34]

Chiral separations are concerned with separating molecules that can exist as nonsupetimposable mirror images. Examples of these types of molecules, called enantiomers or optical isomers are illustrated in Figure 1. Although chirahty is often associated with compounds containing a tetrahedral carbon with four different substituents, other atoms, such as phosphoms or sulfur, may also be chiral. In addition, molecules containing a center of asymmetry, such as hexahehcene, tetrasubstituted adamantanes, and substituted aHenes or molecules with hindered rotation, such as some 2,2 disubstituted binaphthyls, may also be chiral. Compounds exhibiting a center of asymmetry are called atropisomers. An extensive review of stereochemistry may be found under Pharmaceuticals, Chiral. [Pg.59]

Washing and cleaning agents containing salts of maleic acid—furan copolymers (106) form complexes with alkaline-earth ions. These cleaning compositions do not contain phosphoms or nitrogen and find use in metal, foodstuff, and machine dishwashing products. [Pg.82]

The reaction of adipic acid with ammonia in either Hquid or vapor phase produces adipamide as an intermediate which is subsequentiy dehydrated to adiponitrile. The most widely used catalysts are based on phosphoms-containing compounds, but boron compounds and siHca gel also have been patented for this use (52—56). Vapor-phase processes involve the use of fixed catalyst beds whereas, in Hquid—gas processes, the catalyst is added to the feed. The reaction temperature of the Hquid-phase processes is ca 300°C and most vapor-phase processes mn at 350—400°C. Both operate at atmospheric pressure. Yields of adipic acid to adiponitrile are as high as 95% (57). [Pg.220]

A method for making ben2onitri1e by dehydrogenation of the Diels-Alder adduct of butadiene and acrylonitrile also has been described (79). Ben2onitri1e also can be made on a small scale by the dehydration of ben2amide ia an iaert solvent with phosphoms oxychloride or ben2enesulfonyl chloride and an organic amine (80,81). [Pg.225]

As the weld metal solidifies, impurity elements are rejected into the molten weld pool, eg, sulfur and phosphoms in steel welds (Fig. 7) (8). The final weld metal to soHdify, located along the weld centerline at the surface of the weld, has increased levels of these elements, which act to lower the... [Pg.345]

Acetaldehyde reacts with phosphoms pentachloride to produce 1,1-dichloroethane [75-34-3] and with hypochlorite and hypoiodite to yield chloroform [67-66-3] and iodoform [75-47-8], respectively. Phosgene [75-44-5] is produced by the reaction of carbon tetrachloride with acetaldehyde in the presence of anhydrous aluminum chloride (75). Chloroform reacts with acetaldehyde in the presence of potassium hydroxide and sodium amide to form l,l,l-trichloro-2-propanol [7789-89-1] (76). [Pg.51]

A technical quality anhydride, assay about 97% maximum, often contains color bodies, heavy metals, phosphoms, and sulfur compounds. [Pg.79]

Acetyl chlotide was formerly manufactured by the action of thionyl chlotide [7719-09-7], CI2OS, on gray acetate of lime, but this route has been largely supplanted by the reaction of sodium acetate or acetic acid and phosphoms ttichlotide [7719-12-2] (24). A similar route apparently is stiU being used in the Soviet Union (25). Both pathways ate inherently costly. [Pg.81]

Acetyl chloride frequently contains 1—2% by weight of acetic acid or hydrochloric acid. Phosphoms or sulfur-containing acids may also be present in the commercial material. A simple test for purity involves addition of a few drops of Crystal Violet solution in CHCl. Pure acetyl chloride will retain the color for as long as 10 min, but hydrochloric, sulfuric, or acetic acid will cause the solution to become first green, then yellow (34). [Pg.82]

Chloroacetyl chloride is manufactured by reaction of chloroacetic acid with chlorinating agents such as phosphoms oxychloride, phosphoms trichloride, sulfuryl chloride, or phosgene (42—44). Various catalysts have been used to promote the reaction. Chloroacetyl chloride is also produced by chlorination of acetyl chloride (45—47), the oxidation of 1,1-dichloroethene (48,49), and the addition of chlorine to ketene (50,51). Dichloroacetyl and trichloroacetyl chloride are produced by oxidation of trichloroethylene or tetrachloroethylene, respectively. [Pg.89]

Bromoacetic acid can be prepared by the bromination of acetic acid in the presence of acetic anhydride and a trace of pyridine (55), by the HeU-VoUiard-Zelinsky bromination cataly2ed by phosphoms, and by direct bromination of acetic acid at high temperatures or with hydrogen chloride as catalyst. Other methods of preparation include treatment of chloroacetic acid with hydrobromic acid at elevated temperatures (56), oxidation of ethylene bromide with Aiming nitric acid, hydrolysis of dibromovinyl ether, and air oxidation of bromoacetylene in ethanol. [Pg.90]

Various halogenating agents have been used to replace hydroxyl with chlorine or bromine. Phosphoms trihaUdes, especially in the presence of pyridine, are particularly suitable (17,18). Propargyl iodide is easily prepared from propargyl bromide by halogen exchange (19). [Pg.104]

Dichlorobutyne [821-10-3] and dibromobutyne [2219-66-1] are readily prepared by treatment with thionyl or phosphoms haUdes. The less-stable diiodobutyne is prepared by treatment of dichloro- or dibromobutyne with an iodide salt (52). [Pg.105]

Heating butyrolactone with bromine at 160—170°C gives a 70% yield of a-bromobutyrolactone (152). With phosphoms tribromide as catalyst, bromination is accelerated, giving 2,4-dibromobutyric acid, which dehydrobrominates to a-bromobutyrolactone when distilled (153). Chlorination gives a-position monochlorination at 110—130°C and a-dichlorination at 190—200°C (154). [Pg.110]

Pentaerythritol is used in self-extinguishing, non dripping, flame-retardant compositions with a variety of polymers, including olefins, vinyl acetate and alcohols, methyl methacrylate, and urethanes. Phosphoms compounds are added to the formulation of these materials. When exposed to fire, a thick foam is produced, forming a fire-resistant barrier (see Elame retardants) (84—86). [Pg.466]

Analysis of Trace or Minor Components. Minor or trace components may have a significant impact on quaHty of fats and oils (94). Metals, for example, can cataly2e the oxidative degradation of unsaturated oils which results in off-flavors, odors, and polymeri2ation. A large number of techniques such as wet chemical analysis, atomic absorption, atomic emission, and polarography are available for analysis of metals. Heavy metals, iron, copper, nickel, and chromium are elements that have received the most attention. Phosphoms may also be detectable and is a measure of phosphoHpids and phosphoms-containing acids or salts. [Pg.134]

Minerals. Supplementation of macrominerals to mminants is sometimes necessary. Calcium and phosphoms are the minerals most often supplemented in mminant diets. One or both may be deficient, and the level of one affects the utilization of the other. Limestone, 36% calcium, is commonly used as a source of supplemental calcium. Dolomite, 22% calcium oyster sheUs, 35% calcium and gypsum, 29% calcium, are sources of calcium. Bone meal, 29% calcium, 14% phosphoms dicalcium phosphate, 25—28% calcium, 18—21% phosphoms and defluorinated rock phosphate, 32% calcium, 18% phosphoms, are sources of both calcium and phosphoms. Diammonium phosphate, 25% phosphoms phosphoric acid, 32% phosphoms sodium phosphate, 22% phosphoms and sodium tripolyphosphate, 31% phosphoms, are additional sources of phosphoms (5). [Pg.156]

Vitamins A, D, and E are required by mminants and, therefore, their supplementation is sometimes necessary. Vitamin A [68-26-8] is important in maintaining proper vision, maintenance and growth of squamous epitheHal ceUs, and bone growth (23). Vitamin D [1406-16-2] is most important for maintaining proper calcium absorption from the small intestine. It also aids in mobilizing calcium from bones and in optimizing absorption of phosphoms from the small intestine (23). Supplementation of vitamins A and D at their minimum daily requirement is recommended because feedstuffs are highly variable in their content of these vitamins. [Pg.156]

Littie research is available regarding the amounts of vitamins and minerals needed by young mminants. However, it is common to supply calcium, phosphoms, trace-mineralized salt, and vitamins A, D, and E (4). In the absence of a functional mmen, B-vitamins and vitamin K should be... [Pg.157]

The legal basis for the sale of fertilizers throughout the world is laboratory evaluation of content as available nitrogen, phosphorus, and potassium. By convention, numerical expression of the available nutrient content of a fertilizer is by three successive numbers that represent the percent available of N, P20, and K O, respectively. Thus, for example, a 20—10—5 fertilizer contains available nitrogen in the amount of 20% by weight of N, available phosphoms in amount equivalent to 10% of P2O5, and available potassium in amount equivalent to 5% K O. The numerical expression of these three numbers is commonly referred to as the analysis or grade of the fertilizer. Accepted procedures for laboratory analysis are fixed by laws that vary somewhat from country to country. [Pg.214]

In the United States the analytical methods approved by most states are ones developed under the auspices of the Association of Official Analytical Chemists (AOAC) (3). Penalties for analytical deviation from guaranteed analyses vary, even from state to state within the United States (4). The legally accepted analytical procedures, in general, detect the solubiUty of nitrogen and potassium in water and the solubiUty of phosphoms in a specified citrate solution. Some very slowly soluble nutrient sources, particularly of nitrogen, are included in some specialty fertilizers such as turf fertilizers. The slow solubihty extends the period of effectiveness and reduces leaching losses. In these cases, the proportion and nature of the specialty source must be detailed on the labeling. [Pg.214]


See other pages where Phosphomics is mentioned: [Pg.2424]    [Pg.2783]    [Pg.2888]    [Pg.20]    [Pg.24]    [Pg.29]    [Pg.29]    [Pg.107]    [Pg.134]    [Pg.375]    [Pg.464]    [Pg.516]    [Pg.142]    [Pg.143]    [Pg.143]    [Pg.144]    [Pg.144]    [Pg.150]    [Pg.152]    [Pg.212]    [Pg.213]    [Pg.213]    [Pg.213]    [Pg.215]    [Pg.221]   
See also in sourсe #XX -- [ Pg.755 ]




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Nucleophilic addition reactions phosphoms nucleophiles

Palladium complexes phosphoms donors

Pentacoordination, phosphoms

Phosphoms

Phosphoms

Phosphoms donors

Phosphoms fractionation

Phosphoms leaching

Phosphoms oxide

Phosphoms sulfide

Phosphoms ylides

Rhodium complexes phosphoms donors

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