Promoters magnesium

Ito T, Wang J, Lin CH, Lunsford JH. Oxidative dimerization of methane over a lithium-promoted magnesium oxide catalyst. J Am Chem Soc. 1985 107 5062-8. 

A short and efficient asymmetric total synthesis of (—)-ot-kainic acid, which is an important neurotransmitter, has been achieved by means of a metal-promoted, enantioselective ene reaction. This approach provides entry into the kainic acid ring system from a very simple precursor (eq 12). One of the key steps involved (iS, 5 )-r-Bu-box-promoted magnesium(ll) catalysis. In this case. 

OXIDATIVE COUPLING OF METHANE OVER PROMOTED MAGNESIUM OXIDE CATALYSTS RELATION BETWEEN ACTIVITY AND SPECIFIC SURFACE AREA... 

Efstathiou, A.M. and Olympiou, G.G. (2010) Catalyst consisting of platinum supported on chemically promoted magnesium oxide and cerium dioxide towards H2-SCR. EP 2010/003494 Gulf Countries No. 2010-16072. 

Corrosion by Various Chemicals and Environments. In general, the rate of corrosion of magnesium ia aqueous solutions is strongly iafluenced by the hydrogen ion [12408-02-5] concentration or pH. In this respect, magnesium is considered to be opposite ia character to aluminum. Aluminum is resistant to weak acids but attacked by strong alkaUes, while magnesium is resistant to alkaUes but is attacked by acids that do not promote the formation of iasoluble films. 

Magnesium is not attacked seriously by dry chlorine [7782-50-5] iodine [7553-56-2] bromine, or fluorine [7782-41 ] gas. However, the presence of water promotes attack. Similarly, sulfur dioxide, ammonia, and fluorine-containing refrigerants do not attack in the absence of water. 

Calcium sulfamate and magnesium sulfamate are used effectively as a stiffening promoter of concrete and hydrauHc cement (see Cement). 

Of the cations (counterions) associated with polar groups, sodium and potassium impart water solubiUty, whereas calcium, barium, and magnesium promote oil solubiUty. Ammonium and substituted ammonium ions provide both water and oil solubiUty. Triethanolammonium is a commercially important example. Salts (anionic surfactants) of these ions ate often used in emulsification. Higher ionic strength of the medium depresses surfactant solubihty. To compensate for the loss of solubiUty, shorter hydrophobes ate used for appHcation in high ionic-strength media. The U.S. shipment of anionic surfactants in 1993 amounted to 49% of total surfactant production. 

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