This paper is a review on the vapor phase catalytic oxidation of naphthalene. Many workers digged the vapor phase catalytic oxidation of naphthalene because of the paramount interest of phtalic anhydride, the chief product of that oxidation.
M.S. Medimagh, M.L. Bouguerra
An isobaric NaNO2 - NaNO3 phase diagram is obtained using simultaneous thermal analysis technique. The results show the existence of five horizontal lines situated at the following temperatures : 158°C, 177°C, 225°C, 227°C and 229°C. In addition an equimolecular intermediate compound is appearing, which is stable between 177° and 229°C.
H. Zamaly, M. Jemal
Six compounds belonging at the terpern’s and sterols’s groups have been isolated from the roots of Periploca laevigata (Asclepiadacées). Three of them had been caracterized from the stems of this species the others have never been found neither from the stems nor from the roots.
M. Askri, A.M. Bui, Z. Mighri
The calculation of pH is studied as an example of the determination of chemical concentrations in solution, which are involved in one or several equilibrium. With this type of problem, the essential difficulty is the necessity to approximate, using considerations of a chemical order, to simplify the mathematical problem. The aim of this article is to present, using the example of strong or weak acid solutions:
- the systematic method which allows one, in ail cases and without taking into account considerations of a chemical order, to reveal the most simple mathematical relationship that leads to an acceptable value for pH. The relative error not to be exceeded is fixed in advance.
- the treatment of this type of problem by computer, in order to obtain the most simple mathematical relationship that leads to an acceptable value of pH.
J.L. Janier Dubry
“Pure and applied chemistry” (Vol. 51, n° 9, 1979, p: 1995). L’organe de l’IUPAC a proposé de nouvelles règles de nomenclature qui vont être résumées et simplifiées dans ce qui suit, à l’instar de "Chemistry International" (n° 3, 1979, p : 8-9).