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Potassium applications

Killi, F., Ktiqtikler, A.H., and Safjti, H., Effect of different planting dates and potassium applications on tuber yield, yield composition and soluble dry matter content of Jerusalem artichoke (Helianthus tuberosus L.), in Optimizing Crop Nutrition, International Potash Institute, Izmir, Turkey, 2005, pp. 124—129, http //www.ipipotash.org. [Pg.397]

Higher amounts can be found in certain varieties. In L. pimpinellifolum, levels as high as 40 mg per 100 g of fresh tissue have been reported, accounting for more than 95% of the total carotenoid content of these tomatoes (Porter and Lincoln, 1950). Nitrogen fertilizers and calcium sprays (0.2%) were reported to increase the lycopene content of tomatoes. Potassium deficiency may lower lycopene concentration however, very high potassium applications (>800 kg/ha) would cause a marked decrease in color uniformity disorders (Grolier, 2000). [Pg.145]

Humayun M, Clayton RN (1995b) Precise determinations of the isotopic composition of potassium Application to terrestrial rocks and lunar soils. Geochim Cosmochim Acta 59 2115-2130 Inger S, Ramsbottom W, Cliff RA, Rex DC (1996) Metamorphic evolution of the Sesia-Lanzo Zone, Western Alps Time constraints from multi-system geochronology. Contrib Mineral Petrol 126 152-168... [Pg.813]

Phosphoras and potassium index levels are assessed by soil analysis and can be high on the many arable farms. On fields with high reserves, only maintenance dressings are reqitired or, indeed, none at all. AppUcations can be made at any convenient time dining the growing season. If soil levels are very low (index 0 or 1), the fertiliser should either be appUed to the seedbed or combine drilled. Care must be taken with potassium applications if straw is removed from the field rather than incorporated. Barley straw, especially, contains fairly high levels of potassium and removal could well mean that subsequent apphcations of potassium will need to be increased (Table 13.3). [Pg.299]

Some clay soils can release 50 kg/ha of potash annually. On these soils potassium applications should be reduced accordingly. [Pg.300]

The experimental conditions necessary for the preparation of a solution of a diazonium salt, diazotisation of a primary amine, are as follows. The amine is dissolved in a suitable volume of water containing 2 5-3 equivalents of hydrochloric acid (or of sulphuric acid) by the application of heat if necessary, and the solution is cooled in ice when the amine hydrochloride (or sulphate) usually crystallises. The temperature is maintained at 0-5°, an aqueous solution of sodium nitrite is added portion-wise until, after allowing 3-4 minutes for reaction, the solution gives an immediate positive test for excess of nitrous acid with an external indicator—moist potassium iodide - starch paper f ... [Pg.590]

Potassium and sodium borohydride show greater selectivity in action than lithium aluminium hydride thus ketones or aldehydes may be reduced to alcohols whilst the cyano, nitro, amido and carbalkoxy groups remain unaffected. Furthermore, the reagent may be used in aqueous or aqueous-alcoholic solution. One simple application of its use will be described, viz., the reduction of m-nitrobenzaldehyde to m-nitrobenzyl alcohol ... [Pg.881]

Table 8 1 illustrates an application of each of these to a functional group transfer matron The anionic portion of the salt substitutes for the halogen of an alkyl halide The metal cation portion becomes a lithium sodium or potassium halide... [Pg.327]

Hot potassium carbonate is generally considered for bulk acid gas removal applications. Often a secondary removal step using an alkanolamine is also used to meet product specifications. [Pg.212]

Eleetrostatie-type separation is being tested as an alternath c to the presently used process oF Rotation oF pebble phosphates For eoarser-size Fractions, Advantages sought include reduced reagent costs, a lower water requirement, and Fewer tailings-disposal problems when a part oF the Rotation circuit is eliminated. The largest application oF triboeleetrie separation is in the salt industry where sodium and potassium salts are separated aFter preconditioning. [Pg.1807]

Two complementai y reviews of this subject are by Shah et al. AIChE Journal, 28, 353-379 [1982]) and Deckwer (in de Lasa, ed.. Chemical Reactor Design andTechnology, Martinus Nijhoff, 1985, pp. 411-461). Useful comments are made by Doraiswamy and Sharma (Heterogeneous Reactions, Wiley, 1984). Charpentier (in Gianetto and Silveston, eds.. Multiphase Chemical Reactors, Hemisphere, 1986, pp. 104—151) emphasizes parameters of trickle bed and stirred tank reactors. Recommendations based on the literature are made for several design parameters namely, bubble diameter and velocity of rise, gas holdup, interfacial area, mass-transfer coefficients k a and /cl but not /cg, axial liquid-phase dispersion coefficient, and heat-transfer coefficient to the wall. The effect of vessel diameter on these parameters is insignificant when D > 0.15 m (0.49 ft), except for the dispersion coefficient. Application of these correlations is to (1) chlorination of toluene in the presence of FeCl,3 catalyst, (2) absorption of SO9 in aqueous potassium carbonate with arsenite catalyst, and (3) reaction of butene with sulfuric acid to butanol. [Pg.2115]

Potassium (metal). Properties and applications are similar to those for sodium but as the reactivity is greater than that of sodium, the hazards are greater than that of sodium. Handle with extreme care. [Pg.27]

Sodium hydroxide. Properties and applications are similar to those for potassium... [Pg.28]

Resoles are usually those phenolics made under alkaline conditions with an excess of aldehyde. The name denotes a phenol alcohol, which is the dominant species in most resoles. The most common catalyst is sodium hydroxide, though lithium, potassium, magnesium, calcium, strontium, and barium hydroxides or oxides are also frequently used. Amine catalysis is also common. Occasionally, a Lewis acid salt, such as zinc acetate or tin chloride will be used to achieve some special property. Due to inclusion of excess aldehyde, resoles are capable of curing without addition of methylene donors. Although cure accelerators are available, it is common to cure resoles by application of heat alone. [Pg.874]

Though the discussion above was aimed primarily at wood binders, many of the ideas carry over into foundry and glass binding applications. For example, potassium hydroxide is used extensively in foundry binders as are esters and... [Pg.895]

Corrective Action Application At a Navy facility in Guam, approximately 25 tons of PCB contaminated soil was treated using the KPEG (potassium polyethylene glycol) process. PCB concentrations were reduced from 3000 ppm to less than 5 ppm. Upon completion of treatment using the KPEG process, the soil was neutralized from a pH of 14 to 7. A full-scale system for this process is currently under development. [Pg.147]

The application of biosolids also increases the nutritional value of blue grama. Tissue levels of nitrogen, phosphorus, potassium, and crude protein increased to recommended tissue concentrations with biosolids treatments. Trace metals in blue grama grass did not increase during the study, thereby eliminating concerns that toxic amounts of these elements could be transferred to grazing animals. [Pg.581]

There is probably no better evidence for a template effect than its application directly in the solution of a synthetic problem. Rastetter and PhiUion have utilized a substituted 19-crown-6 compound (shown below in Eq. 2.9) in the formation of macrocyclic lactones. Although there were certain experimental variations and the the possibility of intermolecular potassium ion complexation, the overall formation of lactone was favorable. [Pg.17]

Over the years, 18-crown-6 has probably been utilized in more applications than any other erown with the possible exception of dibenzo-18-crown-6. There are several reasons for this. First, simple syntheses of 18-crown-6 have been available for a long time and the molecule may be prepared from very inexpensive starting materials. Equally important, however, is the fact that 18-crown-6 is a very strong binder for a number of alkali metals, especially sodium and potassium cations. [Pg.21]

In specific applications to phase transfer catalysis, Knbchel and his coworkers compared crown ethers, aminopolyethers, cryptands, octopus molecules ( krakenmole-kiile , see below) and open-chained polyether compounds. They determined yields per unit time for reactions such as that between potassium acetate and benzyl chloride in acetonitrile solution. As expected, the open-chained polyethers were inferior to their cyclic counterparts, although a surprising finding was that certain aminopolyethers were superior to the corresponding crowns. [Pg.312]

This formula was confirmed hy Haworth and Perkin s synthesis of a-flZZocryptopine from herherine, the first application of a process, of which examples have heen given already in the syntheses of cryptopine (p. 298) and protopine (p. 301) hy the same authors. Anhydrotetrahydromethyl-herherine (I cf. hase (a), p. 346) in dry chloroform was added to a solution of perhenzoic acid in ether cooled helow 5°. The amine oxide, C21H23O5N (II), separated as an oil, which after shaking with sodium hydroxide solution, solidified and was crystallised from water in slender prisms, m.p. 135°. It was dissolved in acetic acid, hydrochloric acid added, the mixture heated in boiling water for an hour and the hase precipitated hy addition of potassium hydroxide. The precipitate was dissolved in methyl alcohol, ether added, the alcohol washed out with water and the ethereal... [Pg.302]

Aromatic fluorodenitration was first discovered in the reaction of polychloro-nitrobenzenes with potassium fluoride, when 2,3,5,6-tetrachlorofluorobenzene was prepared in 37% yield from 2,3,5,6-tetrachloronitrobenzene 105] The technique has been adapted to prepare aryl fluorides from other activated nitro aromatics for applications in pharmaceutical and polymer chemistry (equation 31) Fluorodenitration also has been applied to prepare radiolabeled ( F) fluo-roaromatics [74, 106]... [Pg.286]

The alkali metals form a homogeneous group of extremely reactive elements which illustrate well the similarities and trends to be expected from the periodic classification, as discussed in Chapter 2. Their physical and chemical properties are readily interpreted in terms of their simple electronic configuration, ns, and for this reason they have been extensively studied by the full range of experimental and theoretical techniques. Compounds of sodium and potassium have been known from ancient times and both elements are essential for animal life. They are also major items of trade, commerce and chemical industry. Lithium was first recognized as a separate element at the beginning of the nineteenth eentury but did not assume major industrial importance until about 40 y ago. Rubidium and caesium are of considerable academic interest but so far have few industrial applications. Francium, the elusive element 87, has only fleeting existence in nature due to its very short radioactive half-life, and this delayed its discovery until 1939. [Pg.68]


See other pages where Potassium applications is mentioned: [Pg.1138]    [Pg.1138]    [Pg.185]    [Pg.219]    [Pg.142]    [Pg.834]    [Pg.847]    [Pg.343]    [Pg.95]    [Pg.588]    [Pg.749]    [Pg.20]    [Pg.183]    [Pg.66]    [Pg.89]    [Pg.99]    [Pg.54]    [Pg.494]    [Pg.572]    [Pg.581]    [Pg.279]    [Pg.172]    [Pg.2]    [Pg.524]    [Pg.963]    [Pg.143]   
See also in sourсe #XX -- [ Pg.28 , Pg.174 , Pg.228 , Pg.229 , Pg.266 , Pg.292 , Pg.340 ]

See also in sourсe #XX -- [ Pg.342 , Pg.346 ]




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