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Wpływ składu chemicznego i więźby szkła popiołowego na właściwości cementu

Tkaczewska E.

Cement Wapno Beton

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2017

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R. 22/84, nr 4

328--336

PL

Uzyskano trzy syntetyczne szkła w laboratorium, które odpowiadały swym składem i właściwościami tej fazie występującej w krzemionkowych popiołach lotnych. Zbadano budowę tych szkieł z zastosowaniem spektroskopii w podczerwieni. Stwierdzono, że syntetyczne szkło o większym stosunku Al2O3/(Na2O+K2O+2CaO) zawiera więcej oktaedrów [AlO6]9- w więźbie, a mniej tetraedrów [AlO4]5-. Oktaedry [AlO6]9- o koordynacji 6 w więźbie szkła syntetycznego zwiększają jego reaktywność, co znajduje potwierdzenie w reakcji pucolanowej, w przypadku jego dodatku do cementu portlandzkiego. Powoduje to zmniejszenie stosunku CaO/SiO2 w fazie C-S-H. Dodatek syntetycznego szkła glinokrzemionkowego, o większym udziale oktaedrów [AlO6]9- w więźbie, przyspiesza hydratację cementu portlandzkiego i korzystnie wpływa na jego wytrzymałość.

EN

The three synthetic glasses were obtained in laboratory, which composition were close to the composition of this phase in siliceous fly ash. The network of these glasses was examined using the infrared spectroscopy. It was establish that the glass with higher ratio Al203/(Na2O+K2+2CaO) the network is richer in [AlO6]9- octahedrons and consequently has lower content of [AlO4]5̵ tetrahedrons. Octahedrons [AlO6]9- are increasing the reactivity of glass, which is confirmed in the case of its addition to Portland cement; it is causing the decrease of CaO/SiO2 of C-S-H phase. Additions of synthetic alumina-siliceous glass, with higher content of [AlO6]9- octahedrons in its network the hydration and strength development of Portland cement is accelerating.

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Synthesis and Physico-Chemical Studies of 14-Membered Tetraazamacrocyclic Complexes of Co(II), Ni(II), Cu(II) and Zn(II) DErived from 3,4-Diaminobenzophenone

Khan T., Ghani S.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 5

817-823

EN

A new series of 14-membered tetraazamacrocyclic complexes [MLX2] (M = Co(II), Ni(II), Cu(II), and Zn(II), X = Cl or NO3) have been synthesized by the condensation reaction of 3,4-diaminobenzophenone with 1,3-dibromopropane in the presence of metal ions as templates in methanol as solvent. The macrocyclic complexes have been characterized on the basis of elemental analysis, IR, 1H NMR, EPR, UV-visible, magnetic susceptibility and conductivity measurements at room temperature. An octahedral geometry has been proposed for all of the complexes where two coordination sites are occupied by Cl or NO3 and the other four sites by secondary amine. The low conductivity data suggests their non-ionic nature.

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Characterization and Antifungal Study of Genuine Oxovanadium (IV) Mixed-Ligand Complexes with Schiff Bases

Parekh H., Pansuriya P., Patel M.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 12

1843-1851

EN

New oxovanadium(IV) complexes [VO(L)(A)] (KHL = potassium salt of o-hydroxyacetophenoneglycine, A1 = 2,2'-bipyridylamine, A2 = bis(benzylidene)ethylenediamine, A3 = thiophene-o-carboxaldeneaniline, A4 = thiophene-o-carboxaldene-p-toluidine, A5 = bis(benzylidene)-1,8-diaminonaphthalene, A6 = bis(acetophenone)ethylenediamine) have been isolated and characterized by elemental analyses, infrared spectra, electronic spectra, magnetic measurement and thermogravimetric analyses. An octahedral geometry has been assigned to all the VO(IV) complexes. The antifungal activity of Schiff bases, oxovanadium(IV) complexes, vanadyl sulphate, control (DMSO) and fungicides (bavistin and emcarb) have been evaluated against A. niger, F. oxysporum and A. flavus, which show clear enhancement in the antifungal activity upon complexation with Schiff bases but moderate activity as compared to the standard fungicides bavistin and emcarb.