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Phosphorus rates

Phosphorus rates have ranged between 14 and 100 kg ha and potassium between 52 and 100 kg-ha Phosphorus fertilization can have a significant effect on tuber sugar content, although the requirements depend heavily on soil type and other agronomic factors (Bachmann, 1964 Kosaric et al., 1984). [Pg.392]

Potentially Mineralizable Phosphorus Rates in the Floe and Surface Soils from Select Hydrologic Units of the Everglades... [Pg.659]

Equip a 1 litre bolt-head flask with dropi)ing fuuncl and a double surface reflux condenser to the top of the latter attach a device (e.g.. Fig. II, 8, 1. c) for the absorption of the hydrogen bromide evolved. Place 100 g. (108 ml.) of dry iso-valeric acid (Section 111,80) and 12 g. of pmified red phosphorus (Section 11,50,5) in the flask. Add 255 g. (82 ml.) of dry bromine (Section 11,49,5) slowly through the dropping funnel at such a rate that little or no bromine is lost with the hydrogen bromide evolved the addition occupies 2-3 hours. Warm the reaction mixture on a water bath until the evolution of hydrogen bromide is complete and the colour of the bromine has disappeared. Pour off the liquid reaction product into a Claisen flask and distil mider the reduced pressure of a water pump. Collect the a-bromo-wo-valeryl bromide at 117-122°/25-30 mm. The yield is 150 g. [Pg.999]

A solution of 0.10 mol of freshly distilled diethylaminopropyne in 80 ml of dry (distilled from phosphorus pentoxide) acetonitrile was cooled to 5°C and dry carbon dioxide was introduced into the vigorously agitated solution at a rate of about 0.3 1/min. The temperature rose above 20°C within a few minutes, but was kept at about 30°C by occasionally immersing the flask in a bath of ice-water. The introduction of CO2 was continued until the temperature had dropped to 25°C and the typical odour of the yneamine had disappeared completely. The yellow solution was concentrated in a water-pump vacuum. The residue, a sirupy liquid, had the theoretically required weight and consisted of reasonably pure (about 955 ) allenyl-diamide. If desired the product car be distilled (short-path distillation) in a high vacuum. It solidified upon standing at -25 C. [Pg.211]

When unsubstituted, C-5 reacts with electrophilic reagents. Thus phosphorus pentachloride chlorinates the ring (36, 235). A hydroxy group in the 2-position activates the ring towards this reaction. 4-Methylthiazole does not react with bromine in chloroform (201, 236), whereas under the same conditions the 2-hydroxy analog reacts (55. 237-239. 557). Activation of C-5 works also for sulfonation (201. 236), nitration (201. 236. 237), Friede 1-Crafts reactions (201, 236, 237, 240-242), and acylation (243). However, iodination fails (201. 236). and the Gatterman or Reimer-Tieman reactions yield only small amounts of 4-methyl-5-carboxy-A-4-thiazoline-2-one. Recent kinetic investigations show that 2-thiazolones are nitrated via a free base mechanism. A 2-oxo substituent increases the rate of nitration at the 5-position by a factor of 9 log... [Pg.402]

Examples P2O5, diphosphorus pentaoxide or phosphorus)V) oxide Hgj, mercury(I) ion or dimercury(2-l-) ion K2[Fe(CN)g], potassium hexacyanoferrate(II) or potassium hexacyanofer-rate(4—) PbJPb 04, dilead(II) lead(IV) oxide or trilead tetraoxide. [Pg.216]

A recent review of research on phosphorus input to surface waters from agriculture highlights the variability of particulate and dissolved phosphorus contributions to catchments. The input varies with rainfall, fertilizer application rates, the history of the application of the fertilizer, land use, soil type, and between surface and sub-surface water. The balance struck between export of nutrients from the catchment and recipient-water productivity is the primary factor which controls its quality. [Pg.29]

Looking at these sources from an algal perspective, evolution in habitats in which soluble sources are deficient or, at best, transiently present in time as well as in space, has provided them with mechanisms to take up soluble phosphorus at rapid rates from low concentrations. Most can satisfy their growth needs at SRP concentrations well below 10 molar, even though maximum uptake... [Pg.33]

It is becoming increasingly clear that, in shallow lakes which have high rates of phosphorus sediment re-cycling, bio-manipulation is an essential element of successful restoration. [Pg.39]

Kinetic studies have shown that the enolate and phosphorus nucleophiles all react at about the same rate. This suggests that the only step directly involving the nucleophile (step 2 of the propagation sequence) occurs at essentially the diffusion-controlled rate so that there is little selectivity among the individual nucleophiles. The synthetic potential of the reaction lies in the fact that other substituents which activate the halide to substitution are not required in this reaction, in contrast to aromatic nucleophilic substitution which proceeds by an addition-elimination mechanism (see Seetion 10.5). [Pg.731]

Fire Hazards - Flash Point (deg. F) 82 - 105 CC (solutions only pure liquid difficult to burn) Flammable Limits in Air (%) Not pertinent Fire Extinguishing Agents (for solutions) Foam, dry chemical, or carbon dioxide Fire Extinguishing Agents Not to be Used Water may be ineffective Special Hazards of Combustion Products Oxides of sulfur and phosphorus are generated in fires Behavior in Fire Not pertinent Igrution Temperature Not pertinent Electrical Hazard Data not available Burning Rate (for solutions) 4 mm/min. [Pg.109]

Phosphinamides are stable to catalytic hydrogenation, used to cleave benzyl-derived protective groups, and to hydrazine. The rate of hydrolysis of phosphinamides is a function of the steric and electronic factors around the phosphorus. This derivative has largely been used for the protection of amino acids and occurs few, if any, times in the general synthetic literature. [Pg.598]

A typical modem phosphorus fumace (12 m diameter) can produce some 4 toniKs per hour and is rated at 60-70 MW (i.e. 140000A at SOOV). Three electrodes, each weighing 60 tonnes, lead in the current. The amounts of raw material required to make 1 tonne of white phosphorus depend on their purity but are typically 8 tonnes of phosphate rock. 2 tonnes of silica, 1.5 tonnes of coke, and 0.4 tonnes of electrode carbon. The phos rfKmis vapour is driven off from the top of the fumace together with the CO and some H2 it is passed through a hot electrostatic precipitator to remove dust and then condensed by water sprays at about 70 (P4 melts at 44.T). The byproduct CO is used for supplementary heating. [Pg.480]

Oxoacids of phosphorus and their salts Table 12.10 Factors affecting the rate of polyphosphate degradation... [Pg.523]

Ethyl N-phthaloyl p-aminophenylalaninate (3.15 g) (unrecrystallized) was suspended in water (50 g) and glacial acetic acid (30 g) added. To the clear solution, ethylene oxide (8.0 g) was added, the mixture allowed to stand for 17 hours, and then poured into water (350 g). The solution was neutralized with sodium hydrogen carbonate and the liberated gum extracted with ether. The ethereal solution was dried (magnesium sulfate) and eyapo-rated. The residual gum (3.95 g) was dissolved in benzene (50 g) and the solution dried azeotropically by distilling off some of the solvent. Freshly distilled phosphorus oxychloride (8 g) was added and the mixture heated under reflux for 30 minutes. [Pg.926]

Chromium, in fractional percentages, has a significant influence on corrosion rates. While it appears to be beneficial, some conflicting results have been reported and its contribution to the reduced corrosion of complex low-alloy steels containing copper and phosphorus is not large. [Pg.511]

The British Non-Ferrous Metals Research Association carried out two series of tests, the results of which have been given by Gilbert and Gilbert and Porter these are summarised in Table 4.12. In the first series tough pitch copper tubes were exposed at seven sites for periods of up to 10 years. The two most corrosive soils were a wet acid peat (pH 4-2) and a moist acid clay (pH 4-6). In these two soils there was no evidence that the rate of corrosion was decreasing with duration of exposure. In the second series phosphorus-deoxidised copper tube and sheet was exposed at five sites for five years. Severe corrosion occurred only in cinders (pH 7 1). In these tests sulphides were found in the corrosion products on some specimens and the presence of sulphate-reducing bacteria at some sites was proved. It is not clear, however, to what extent the activity of these bacteria is a factor accelerating corrosion of copper. [Pg.693]


See other pages where Phosphorus rates is mentioned: [Pg.319]    [Pg.340]    [Pg.189]    [Pg.282]    [Pg.283]    [Pg.288]    [Pg.304]    [Pg.431]    [Pg.1]    [Pg.97]    [Pg.20]    [Pg.91]    [Pg.29]    [Pg.34]    [Pg.41]    [Pg.103]    [Pg.149]    [Pg.9]    [Pg.102]    [Pg.407]    [Pg.39]    [Pg.128]    [Pg.318]    [Pg.402]    [Pg.405]    [Pg.571]    [Pg.581]    [Pg.207]    [Pg.457]    [Pg.151]    [Pg.1280]    [Pg.513]    [Pg.640]   
See also in sourсe #XX -- [ Pg.698 ]




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