Diiron complexes containing pyridyl-phosphine ligands, that is, (mu-pdt)[Fe(2)(CO)(5)L] (pdt = S(CH(2))(3)S, L = Ph(2)PCH(2)Py, Ph(2)PPy, ) and (micro-pdt)[Fe(CO)(2)(PMe(3))][Fe(CO)(2)L] (L = Ph(2)PCH(2)Py, Ph(2)PPy, ) were prepared as model complexes of the [FeFe]-hydrogenase active site. Protonation of and by HOTf afforded the pyridyl-nitrogen protonated products [H(N)][OTf] and [H(N)][OTf], ...

abstract: fermented cucumber is a traditional lactic acid fermentation that is related to the presence of microorganisms. in this study, the use of suitable l. plantarum starter culture with l.bulgaricus and s. thermophilus to improve the cucumber fermentation process with high quality has been studied. cucumbers in brine containing 4 to 6% nacl and 0.2 to 0.4% inulin (w/v) were inoculated with...

We studied responses of cork oak (Quercus suber L.) to iron (Fe) deficiency by comparing seedlings grown hydroponically in nutrient solution with and without Fe. Seedlings grown without Fe developed some responses typical of the Strategy I group of Fe-efficient plants, including two- and fourfold increases in plasma membrane ferric chelate reductase activity of root tips after 2 and 4 weeks of ...

OBJECTIVES This study aimed to analyse the erosion-inhibiting potential of a single application of stannous chloride-containing fluoride solution on pellicle-covered enamel and dentine under constant acid flow conditions in vitro. DESIGN Bovine enamel (n=60) and dentine (n=60) samples were exposed 1h to the oral cavity of 4 healthy volunteers to allow for in situ pellicle formation. Pellicle-...

The nature and photoelectrochemical reactivity of nanoporous semiconductor electrodes have attracted a great deal of attention. Nanostructured materials have promising capabilities applicable for the construction of various photonic and electronic devices. In this paper, a mesoporous TiO(2) thin film photoanode was soaked in an aqueous methanol solution using an O(2)-reducing Pt-based cathode i...

Milk and milk products, such as cheese, have been shown to exhibit anticariogenic properties in human and animal models. CPP-ACP shows an anti-caries effect by suppressing demineralization, enhancing remineralization, or possibly a combination of both. The purpose of this study was to evaluate the effect of CPP-ACP paste on demineralization by observing the treated tooth surface using an FE-SEM...

Generated by zinc hydrometallurgical production and containing several toxic species, jarosite has been little used or beneficiated to date. Utilization of can save mining resources producing valuable products, reduce potential hazards from disposal. To avoid high energy consumption as in the roasting steps current process, hydrometallurgy various an original process aimed at zinc-iron alloys i...

Pollutants have adverse effects on human health and on other organisms that inhabit or use water resources. The aim of the present study was to assess the environmental quality of three watercourses in Monte Carmelo, MG, Brazil, using the micronucleus test on Tradescantia. For each treatment, 15 plants were exposed to water samples for 24 h. The control group was exposed to formaldehyde (0.2%) ...