A new material based on montmorillonite and Cu(II)-phenanthroline complex for effective capture of ammonia from gas phase

The intercalation of [Cu(Phen)(H2O)2]2+ (CuPhen) in montmorillonite (Mt) produces a stable hybrid material that is very efficient in removing NH3 from gas phase even at extremely low pressures. The process was studied by elemental analysis, X-ray powder diffraction, thermal analysis coupled with evolved gas mass spectrometry and DR UV–Vis, NMR and X-ray absorption spectroscopy. The adsorption of CuPhen on Mt consists of two consecutive steps. During the first one, CuPhen intercalates alone into Mt through a cation exchange process, afterwards CuPhen and SO42− ions entry jointly into the mineral interlayer. The two-steps adsorption process is described by a VI-type isotherm, successfully fitted by two independent Frumkin isotherms. NH3 trapping is long-lasting, easy, fast even at extremely low gas pressure and reversible under mild conditions. Mt containing CuPhen always results well performant in removing ammonia from gas phase, but an appreciably higher adsorption capacity of NH3 is obtained when SO42− ion is absent from the interlayer. This hybrid montmorillonite is thus a promising material to be used in industrial or environmental contexts, as an efficient air-cleaner

Nitrogen pools in tropical plantations of N2-fixing and non-N2-fixing legume trees under different tree stand densities.

We investigated the nitrogen pools in monocultures of legume species widely used in reforestation in Brazil that have contrasting growth and nitrogen acquisition strategies. The plantations were established with the slow-growing and N2-fixing tree Anadenanthera peregrina var. peregrina, and the fast-growing and non-fixing tree Schizolobium parahyba var. amazonicum. The measurements of N pools in the tree biomass and the soil followed standard methods and were carried out on 54 experimental plots. The N2 fixation pools were evaluated by abundance natural of 15N and the N accretion methods. The soil N content was of similar magnitude between species and stand densities. The species showed similar amounts of N in the biomass, but divergent patterns of N accumulation, as well as the 15N signature on the leaves. S. parahyba accumulated most N in the stem, while A. peregrina accumulated N in the roots and leaves. However, the N accumulation in biomass of A. peregrina stand was less constrained by environment than in S. parahyba stands. The percentage of N derived from N2 fixation in A. peregrina stands decreased with the increase of stand density. The biological N2 fixation estimates depended on the method and the response of tree species to environment

Automated Multiple Development HPTLC Analysis of Sugar on Hydrophilic Layers: II. Diol Layers

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Localized gastric amyloidosis. Clinico-radiologic aspects

No abstract availabl

Determination of metals in multicomponent system by differential pulse and alternating current anodic stripping voltammetry

A combination of sensitive and selective voltammetric methods, namely differential pulse (DPASV) and fundamental and second harmonic alternating current anodic stripping voltammetry (ACASV) were found to be very suitable techniques for the simultaneous determination of metal species having half-wave potentials close to one another. The simultaneous determination of traces of CuII, BIII, SbIII, PbII, CdII and SnII is described using 0.1 M HCl as the supporting electrolyte with the subsequent addition of 0.02 M EDTA or 1.0 M NaOH (for the analysis of CuII, SbIII and SnII, respectively). A semistationary mercury electrode (long lasting sessile drop mercury electrode) was used as the working electrode. A saturated calomel electrode (SCE) and a platinum electrode were used as the reference and auxiliary electrodes, respectively. The analytical procedure was verified with the analysis of standard reference material NBS-SRM 631 Spectrographic Zinc Spelter LV1. Precision and accuracy, expressed as relative standard deviation and relative error, respectively, were 3 to 5%, while the detection limits were of the order of 10-8 to 10-10 M in the case of element examined

Gaseous heptanethiol removal by a fe3+-phenanthroline-kaolinite hybrid material

Kaolinite functionalized by the μ-oxo Fe3+-phenanthroline complex (Fe+3Phen) was selected to test its ability to efficiently remove and store gaseous heptanethiol (HPT). Spectroscopic techniques, elemental analysis, and thermal analysis coupled with evolved gas mass spectrometry were employed to characterize the material before and after the exposure to the gas and to define the adsorption process. The amount of HPT trapped by the functionalized kaolinite after 60 days is 0.10940 moles per 100 g of kaolinite which, considering the amount of adsorbed Fe+3Phen (0.00114 moles per 100 g of kaolinite), means a thiol/Fe3+Phen molar ratio of about 100:1, a value much higher than those found in the past for Fe+3Phen functionalized montmorillonite and sepiolite. In addition, the process was found to be efficient also beyond 60 days. This significant removal of the smelly gas was explained by considering a continuous catalytic activity of Fe3+ toward the oxidation of thiol to disulfide

Randomized, double-blind, placebo-controlled study on the antihypertensive effects of Grana Padano D.O.P. cheese consumption in mild-moderate hypertensive subjects

OBJECTIVE: Grana Padano, an Italian protected designation of origin (PDO) semi-fat cheese, undergoes a long ripening period during which the proteolysis carried out by natural starter lactic acid bacteria releases peptides having sustained angiotensin-converting enzyme (ACE)-inhibitory activity. The length (generally 3-8 amino acid residues) and the sequence of these peptides are responsible for their ability to elicit ACE-inhibitory activity. The aim of this study has been the evaluation of the effect of a daily dietary supplement consisting in a small amount (30 g/day) of Grana Padano cheese, in terms of the lowering of the blood pressure (BP) of mild-moderate hypertensive subjects. PATIENTS AND METHODS: Thirty mild-moderate hypertensive patients, with BP values not on target (> 140 and/or > 90 mmHg) after at least 3 months of stable treatment were considered in this randomized, double-blind placebo-controlled cross-over study. All patients randomly received a dietary integration (30 g/day) of Grana Padano cheese or a placebo (made from flavored grated bread mixed with fats and salts in concentrations equal to those of the cheese). BP was evaluated at baseline and at the end of the active and placebo treatments (2 months each) by: - Office BP (OBP); - Automated Office BP (AOBP) using the BpTRU\uae, an automated oscillometric device that provides the average of multiple (n=6) blood pressure measurements; - Ambulatory Blood Pressure (ABP) 24 hour monitoring. RESULTS: Dietary integration with Grana Padano cheese resulted in a significant decrease in Office, Automated Office and Ambulatory BP. The mean decrease (vs. placebo) for 24-hour ABP was -3.5 mmHg for systolic and -2.4 mmHg for diastolic BP (p = 0.0063 and p = 0.0065, respectively). CONCLUSIONS: Daily dietary integration with 30 g of Grana Padano DOP cheese effectively reduces BP and may help mild-to-moderate hypertensive patients to reach a target BP

Magrezza e calo ponderale in una adolescente: è sempre DCA?

Caso clinico di una adolescente, ricoverata per calo ponderale e "difficltà all'alimentazione". Gli esami ematochimici sono risultati nella norma. E' stato escluso un disturbo del comportamento alimentare (DCA) e per il persistere della sintomatologia, è stata eseguita una gastroscopia cha ha evidenziato una gastrite cronica. Per la persistenza dei sintomi, è stata eseguita una radiografia del tubo digerente che ha evidenziato una acalasia esofagea, con conseguente intervento chirurgico