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Phosphorus-containing chemicals

Four nitrogen- and/or phosphorus-containing chemicals were tentatively identified through direct injection of the sample by GC/NPD. Subsequent confirmation was achieved by running the same aliquot by GC/EIMS, under similar chromatographic conditions and using the same stationary phase column, although hydrocarbons from diesel were present in... [Pg.100]

The experimental conditions are the following spectral ranges (all approximate) are from —0.5 to 11 ppm in H NMR, from —40 to 120 ppm in 31P 1H and 31P NMR (certain types of phosphorus-containing chemicals, e.g. phosphonites and phosphites, may have larger chemical shifts and their observation needs an extended spectral window),... [Pg.328]

Indicative structural details may be revealed for example, methyl, ethyl, propyl, and isopropyl groups directly linked to phosphorus will show different resonance patterns in H NMR spectra. The 31 P H NMR spectrum can reveal the presence of phosphorus-containing chemicals, and in the case of a large coupling constant (due to a P—F bond see Figure 2(b)), also the presence of fluorine. The number of resonances and their integrated areas may give an idea of the number of chemicals present. [Pg.343]

Some good books are available on some of the subjects discussed in this article, for example, on combination of chromatography and FTIR (2), FTIR spectroscopy in general (3,4), and IR spectra of phosphorus-containing chemicals (5). [Pg.354]

Because the radiation emitted from carbon-14 atoms can be detected outside of the system into which the carbon-14-containing molecules have been placed, the location of changes involving carbon can be traced. Likewise, phosphorus-32 atoms can be used to trace phosphorus-containing chemicals as they move from the soil into plants. [Pg.735]

Flame retardants reacted with the polymer backbone usually provide protection at lower levels and thus have a smaller, usually malign, influence on the compound s mechanical and physical properties. In the case of phosphorus-containing chemicals utilised for FR purposes, there exists a... [Pg.33]

FPD for CWA detection is considered semi-selective in the sense that it responds to all sulfur/phosphorus-containing chemicals. Without a means of compound separation, the FPD detector is not capable of distinguishing whether the detected signal derives from a CWA or another substance containing phosphorous and/or sulfur. [Pg.136]

Not only do heavy-metal ions catalyze the destruction of peroxide compounds but they also catalyze other chemical processes caused by oxygen and air. Sequestering these metal ions by phosphorus-containing compounds will decrease their undesired effects. [Pg.601]

As a result of different chemical surroundings the resonance frequency absorption will show definite peaks registered by Fourier transform technique. Compared to an internal standard the intensity of the signals is used for quantitative determination of different phosphorus-containing compounds in a given sample. [Pg.617]

From Table 14-5 it is obvious that the residence time of P in the atmosphere is extremely short. This does not represent chemical reaction and removal of P from the atmosphere but rather the rapid removal of most phosphorus-containing particles that enter the atmosphere. [Pg.371]

The aim of this review is to present the state-of-the-art concerning the synthesis and the chemical properties of phosphorus-containing dendrimers with emphasis made on the specificity introduced by phosphorus. [Pg.90]

Also, 13C NMR assignments have been published for a recently synthesized phosphorus-containing ring system imidazo[l,2-r-][l,3,2]oxazaphosphinine 49 <1996TL977>. The chemical shifts as well as the /C P coupling constants are shown in Table 2. [Pg.962]

Dobolyi and Bidlo [76] determined the phosphorus-containing minerals in Balatien lake sediment, and thus the forms in which the phosphorus responsible for the accelerating eutrophication of the lake are present. Samples were subjected to chemical, electron microscope and X-ray analysis. Hydroxylapatite was identified, but no proof of the presence of other phosphorus minerals was obtained. [Pg.337]

Verona and Picci (U9) have shown that the phosphorus contained in Hanane was used by the soil microbes for their nutrition in relation with studies conducted on the breakdown of systemic insecticides. Pianka, as cited by Nicol (32), has reported that it is possible to enhance the activity of systemic insecticides by the addition of certain chemicals not necessarily systemic. Samples of dimefox activated by... [Pg.23]

Because muscle cells are especially rich in terms of phosphorus-containing metabolites (e.g., ATP, ADP, phos-phocreatine, and orthophosphate), nuclear magnetic resonance " has proved to be a valuable noninvasive probe of metabolic changes attending muscle activity. The spectral sensitivity of P is especially high relative to other nuclei, and one can detect cellular concentrations as low as 0.5 mM as well as utilize chemical shift data to define intracellular pH and free magnesium ion concentrations. See also Nuclear Magnetic Resonance Chemical Shift... [Pg.564]

Toxic phosphorus-containing organic fluorides were mainly developed and produced in the past as nerve gases in chemical warfare or intermediates therefore (Table 22).57-11 1 112 1 15-21 1 Published toxicological data for this reason are rather limited. [Pg.50]

Figure 2.22 Examples of important anthropogenic chemicals exhibiting a phosphorus-containing functional group. Some of the common uses of the chemicals are given in parentheses. Figure 2.22 Examples of important anthropogenic chemicals exhibiting a phosphorus-containing functional group. Some of the common uses of the chemicals are given in parentheses.
The biochemical investigation of DNA began with Friedrich Mescher, who carried out the first systematic chemical studies of cell nuclei. In 1868 Mescher isolated a phosphorus-containing substance, which he called nuclein, from the nuclei of pus cells (leukocytes) obtained from discarded surgical bandages. He found nuclein to consist of an acidic portion, which we know today as DNA, and a basic portion, protein. Mescher later found a similar acidic substance in the heads of sperm cells from salmon. Although he partially purified nuclein and studied its properties, the covalent (primary) structure of DNA (as shown in Fig. 8-7) was not known with certainty until the late 1940s. [Pg.280]


See other pages where Phosphorus-containing chemicals is mentioned: [Pg.101]    [Pg.333]    [Pg.369]    [Pg.790]    [Pg.834]    [Pg.424]    [Pg.257]    [Pg.101]    [Pg.333]    [Pg.369]    [Pg.790]    [Pg.834]    [Pg.424]    [Pg.257]    [Pg.89]    [Pg.798]    [Pg.312]    [Pg.138]    [Pg.300]    [Pg.186]    [Pg.68]    [Pg.245]    [Pg.309]    [Pg.157]    [Pg.728]    [Pg.238]    [Pg.10]    [Pg.193]    [Pg.76]    [Pg.775]    [Pg.362]    [Pg.76]    [Pg.6]    [Pg.387]    [Pg.946]    [Pg.1278]   


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