Nitrate oceans

Pipeline systems for transporting anhydrous ammonia that are urea and ammonium nitrate (UAN) and LNG compatible, exist in Europe, Mexico, and the Soviet Union. Export-oriented ammonia producing countries utilize huge ocean-going tankers that contain up to 50,000 t for distribution of ammonia. Co-shipment in refrigerated LNG tankers is usuaky done. 

Vapor-phase inhibitors are volatile compounds that adsorb onto metal surfaces, and retard or prevent corrosion by a variety of mechanisms (37). Inhibitors such as dicyclohexamine nitrate [3882-06-02] can protect a variety of metals such as steel, aluminum, and tinplate. A number of vapor-phase inhibitors are commercially available as powders or tablets. However, vapor-phase inhibitors attack nonferrous metals to varying degrees, thus the manufacturers recommendations should be checked before appHcation. The system to be protected must be closed to maintain the volatile compound, but objects as large as the interior of an ocean-going tanker have been treated by this technique. 

Other limitations on phytoplankton growth are chemical in nature. Nitrogen, in the form of nitrate, nitrite and ammonium ions, forms a basic building material of a plankton s cells. In some species silicon, as silicate, takes on this role. Phosphorus, in the form of phosphate, is in both cell walls and DNA. Iron, in the form of Fe(III) hydroxyl species, is an important trace element. Extensive areas of the mixed layer of the upper ocean have low nitrate and phosphate levels during... 

Sodium, 22 700 ppm (2.27%) is the seventh most abundant element in crustal rocks and the fifth most abundant metal, after Al, Fe, Ca and Mg. Potassium (18 400 ppm) is the next most abundant element after sodium. Vast deposits of both Na and K salts occur in relatively pure form on all continents as a result of evaporation of ancient seas, and this process still continues today in the Great Salt Lake (Utah), the Dead Sea and elsewhere. Sodium occurs as rock-salt (NaCl) and as the carbonate (trona), nitrate (saltpetre), sulfate (mirabilite), borate (borax, kemite), etc. Potassium occurs principally as the simple chloride (sylvite), as the double chloride KCl.MgCl2.6H2O (camallite) and the anhydrous sulfate K2Mg2(S04)3 (langbeinite). There are also unlimited supplies of NaCl in natural brines and oceanic waters ( 30kgm ). Thus, it has been calculated that rock-salt equivalent to the NaCl in the oceans of the world would occupy... 

Nordhftuser Schwefelsaure, Nordhftuser Vitri-oloL Nordhausen acid (fuming sulfuric acid), nordisch, a. northern, northerly, Nordic, nordlich, a. northerly, northern, arctic. Nord-licht, n. aurora borealis, -meer, n. Arctic Ocean, -ost, m. northeast northeaster, -pol, m. north pole. -see,/. North Sea. Norgeraniumsaure,/. norgeranic acid. Norgesalpeter, m. Norway saltpeter (calcium nitrate). 

Over 20% of the world s open ocean surface waters are replete in light and major nutrients (nitrate, phosphate, and silicate), yet chlorophyll and productivity values remain low. These so-called "high-nitrate low-chlorophyll" or HNLC regimes (Chisholm and Morel, 1991) include the sub-arctic North Pacific (Martin and Fitzwater, 1988 Martin et al, 1989 Miller et al, 1991), the equatorial Pacific (Murray et al, 1994 Fitzwater et al, 1996) and the southern Ocean (Martin et al.,... 

The moles X/moles P in average plankton is given by a, and b is the surface water concentration in phosphorus free water (water stripped of nutrients). In the case of P itself the surface ocean concentration is close to zero, while the deep Pacific has a concentration of 2.5 pM. For N, the N/P ratio of plankton is 16 and the surface water concentration is 0 pM. The predicted deep sea nitrate is 40 pM. The ratio of (deep)/(surface) is greater than 10. For calcium the Ca/P of... 

Figure 3. Time series of nitrate (Slagle and Heimerdinger 1991) and dissolved, particulate, and total in surface water at 47°N, 20°W (Atlantic Ocean) in April-May 1989. activity calculated as 0.0686 salinity (Chen et al. 1986). The production of biogenic particles during the bloom enhances the scavenging of Th, resulting in growing disequilibrium with time due to sinking of particles.

According to Summers and Chang from NASA s Ames Research Center, Moffett Field (1993), the oxidation of Fe2+ to Fe3+ provided a possibility for the reduction of nitrites and nitrates to ammonia. This reaction would have been of great importance, as NH3 is required in many syntheses of biogenesis precursors. The authors assume that nitrogen was converted to NO in a non-reducing atmosphere, and thence to nitrous and nitric acids. These substances entered the primeval oceans in the form of acid rain , and here underwent reduction to NH3 with the help of Fe2+, thus raising the pH of the oceans to 7.3. Temperatures above 298 K favoured this reaction, which can be written as ... 

Sigman et al. [134] have pointed out that nitrate is the predominant form of bioavailable (or fixed ) nitrogen in the ocean, and the natural isotopic... 

The National Research Council of Canada has undertaken a project, in collaboration with Bedford Institute of Oceanography of the Canadian Department of Fisheries and Oceans, to address the need for a seawater certified reference material for micronutrients with the initial objective being the preparation of a material with certified values for nitrate, phosphate, and dissolved silica. 

Ogura and Hanya [62-65] investigated the components of the ultraviolet absorption in an attempt to devise a useful method for oceanic dissolved organic carbon measurements. They concluded that while the method might have limited application in coastal waters, most of the absorption in oceanic waters was due to the inorganic components, principally nitrate and bromide ions. 

Altabet, M.A., and R. Francois. 1994. Sedimentary nitrogen isotopic ratio as a recorder for surface ocean nitrate utilization. Global Biogeochemical Cycles 8(1) 103-116. 

Sarmiento, J.L., T.M.C. Hughes, R.J. Stouffer, and S. Manabe. 1998. Simulated response of the ocean carbon cycle to anthropogenic warming. Nature 393(6682) 245-249. Sarmiento, J., G. Theile, R.M. Key, and W.S. Moore. 1990. Oxygen and nitrate new production and remineralization in the North Atlantic subtropical gyre. Journal of Geophysical Research 95 18303-18315. 

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