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15N and 14N NMR spectra show that there is no valence tautomerism involving the nitro group in nitro derivatives of benzofuroxan systems and that the N-oxide function has a fixed position in the furoxan ring. Carbon chemical shifts of molecules with one, two or three furoxan rings attached to a benzene ring reveal additivity of effects which makes possible a complete and unambiguous assignment of the shifts.

Solvent effects on nitrogen shieldings are shown to vary from almost zero to about 26 ppm. These shielding variations can be analysed in terms of a variety of hydrogen bonding interactions and non-specific solute-solvent interactions. Steric effects are also taken into account. The non-specific interactions are found to be well accounted for by INDO/S-SOS shielding calculations incorporating the solvaton model. Nitrogen NMR is shown to be very suitable for distinguishing between a variety of solute-solvent interactions.

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The article presents an outline of the new technology of pyrometallurgical processing of slag in the direct-to-blister process. The analysis is based on the example of the production process of KGHM Polish Copper SA. A new way of implementing the technology of recovery of copper from the flash furnace slag by means of different feedstocks has been proposed. The method of controlling the processes is another innovation discussed in the paper. The presented concept intensify the reduction reactions, using the Carbo-N-Ox method, of copper compounds to forms of metallic phases in the slag. The processes of coagulation are accelerated and the processes crystallization of metallic phases are under control.Keywords: slag, decopperisation, reagents, recycling W artykule przedstawiono zarys nowej technologii pyrometalurgicznego przetwarzania żużli w procesie jednostadialnego otrzymywania miedzi. Zaproponowano nowy sposób realizacji technologii odzyskiwania miedzi z żużli z pieca zawiesinowego z zastosowaniem odmiennych materiałów wsadowych. Zaproponowano sposób sterowania procesami. Proponowana koncepcja prowadzi do intensyfikowania reakcje redukcji związków miedzi, metodą Carbo-N-Ox, do postaci faz metalicznych w żużlu. Przyspieszone też zostaną procesy koagulacji faz metalicznych. Zaproponowany został sposób analizy formowania się faz metalicznych w żużlu.

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The article describes the optimization of the melting brass. Brasses, as one of the most popular alloys of copper, deserve special attention in the context of the processes of melting, which in turn would provide not only products of better quality, but also reduce the cost of their production or refining. For this purpose, several studies carried out deriatographic (DTA) and thermogravimetric (TG) using derivatograph. The results were confronted with the program SLAG - PROP used to evaluate the physicochemical properties of the coatings extraction. Based on the survey and analysis of the program can identify the most favorable physico - chemical properties, which should be carried out treatments. This allows for slag mixtures referred configurations oxide matrix containing specific stimulators of the reaction. Conducted empirical studies indicate a convergence of the areas proposed by the application. It should also be noted that the program also indicates additional areas in which to carry out these processes would get even better, to optimize the melting process, the results.

"N NMR data and semiempirical molecular orbital calculations are reported for dibenzo-[1,3a,4,6a]tetrazapentalene (1). The "N signals were assigned by means of the results of the molecular orbital calculations and measured relative signal widths. A comparison was made with results for some azolopyridines. A linear correlation was obtained between the nitrogen shieldings, expressed with respect to the bridging nitrogen atom, and the corresponding relative charge densities. Thus nitrogen nuclear shielding results provide a good estimation of electron charge distribution in these molecules. Compound 1 provides the first case in which the shielding of a pyridine-type nitrogen atom is greater than that of the indolizine-type nitrogen.