Lignin biodegradation in pulp-and-paper mill wastewater by selected white rot fungi

An investigation has been carried out to explore the lignin-degrading ability of white rot fungi, as B. adusta and P. crysosporium, grown in different media containing (i) glucose and mineral salts; (ii) a dairy residue; (iii) a dairy residue and mineral salts. Both fungi were then used as inoculum to treat synthetic and industrial pulp-and-paper mill wastewater. On synthetic wastewater, up to 97% and 74% of lignin degradation by B. adusta and P. crysosporium, respectively, have been reached. On industrial wastewater, both fungal strains were able to accomplish 100% delignification in 8-10 days, independent from pH control, with a significant reduction of total organic carbon (TOC) of the solution. Results have confirmed the great biotechnological potential of both B. adusta and P. crysosporium for complete lignin removal in industrial wastewater, and can open the way to next industrial applications on large scale

Mercury speciation in the colloidal fraction of a soil polluted by a chlor-alkali plant: a case study in the South of Italy

Mercury (Hg) speciation in different size fractions of a soil sample collected near an industrial area located in the South of Italy, which had been polluted by the dumping of Hg-containing wastes from a chlor-alkali plant, was investigated by XANES spectroscopy. In particular, a special procedure has been developed to study the soil colloidal fraction, both for sample preparation and for XANES data collection. In this soil, Hg was speciated in quite insoluble inorganic forms such as cinnabar (alpha-HgS), metacinnabar (beta-HgS), corderoite (Hg3S2Cl2), and some amorphous Hg, S and Cl-containing species, all derived from the land-disposal of K106 Hg-containing wastes. The contribution of the above-mentioned chemical forms to Hg speciation changed as a function of particle size. For the fraction corderoite (26%) > cinnabar (20%) = metacinnabar (20%); for the fraction metacinnabar (24%) > corderoite (20%) > cinnabar (16%); and for the fraction 430-650 nm, where most of the colloidal Hg was concentrated: amorphous Hg-S-Cl (56%) > metacinnabar (33%) > corderoite (6%) > cinnabar (5%). From these data it emerged that, even if Hg was speciated in quite insoluble forms, the colloidal fraction, which is the most mobile and thus the most dangerous, was enriched in relatively more soluble species (i.e. amorphous Hg-S-Cl and metacinnabar), as compared with cinnabar. This aspect should be seriously taken into account when planning environmental risk assessment, since the small particle size in which Hg is concentrated and the changing speciation passing from millimetre to nanometre size could turn apparently safe conditions into more hazardous ones

Periodic Active Case Finding for TB: When to Look?

OBJECTIVE: To investigate the factors influencing the performance and cost-efficacy of periodic rounds of active case finding (ACF) for TB. METHODS: A mathematical model of TB dynamics and periodic ACF (PACF) in the HIV era, simplified by assuming constant prevalence of latent TB infection, is analyzed for features that control intervention outcome, measured as cases averted and cases found. Explanatory variables include baseline TB incidence, interval between PACF rounds, and different routine and PACF case-detection rates among HIV-infected and uninfected TB cases. FINDINGS: PACF can be cost-saving over a 10 year time frame if the cost-per-round is lower than a threshold proportional to initial incidence and cost-per-case-treated. More cases are averted at higher baseline incidence rates, when more potent PACF strategies are used, intervals between PACF rounds are shorter, and when the ratio of HIV-negative to positive TB cases detected is higher. More costly approaches, e.g. radiographic screening, can be as cost-effective as less costly alternatives if PACF case-detection is higher and/or implementation less frequent. CONCLUSION: Periodic ACF can both improve control and save medium-term health care costs in high TB burden settings. Greater costs of highly effective PACF at frequent (e.g. yearly) intervals may be offset by higher numbers of cases averted in populations with high baseline TB incidence, higher prevalence of HIV-uninfected cases, higher costs per-case-treated, and more effective routine case-detection. Less intensive approaches may still be cost-neutral or cost-saving in populations lacking one or more of these key determinants

DETERMINATION OF VOLATILE AND NONVOLATILE ORGANIC-ACIDS IN TECHNICAL SUGAR SOLUTIONS BY ION-EXCLUSION CHROMATOGRAPHY

Volatile and non volatile organic acids present in sugar process juices were separated by ion-exclusion chromatography on an HPICE-AS1 cation-exchange column coupled with an anion-exchange micromembrane suppressor and a conductivity detector

HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC DETERMINATION OF PHENOLS AS 4-AMINOANTIPYRINE DERIVATIVES - SILVER-CHLORIDE AS OXIDIZING-AGENT IN THE DERIVATIZATION REACTION

HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC DETERMINATION OF PHENOLS AS 4-AMINOANTIPYRINE DERIVATIVES - SILVER-CHLORIDE AS OXIDIZING-AGENT IN THE DERIVATIZATION REACTIO

HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC DETERMINATION OF NAPHTHOLS AS 4-AMINOANTIPYRINE DERIVATIVES - APPLICATION TO CARBARYL

HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC DETERMINATION OF NAPHTHOLS AS 4-AMINOANTIPYRINE DERIVATIVES - APPLICATION TO CARBARY

CHROMOSORB-101 AS A PACKING MATERIAL FOR REVERSED-PHASE CHROMATOGRAPHY

CHROMOSORB-101 AS A PACKING MATERIAL FOR REVERSED-PHASE CHROMATOGRAPH

Stochastic theory of chromatography. The characteristic function method and the approximation of chromatographic peak shape

NATO ASI serie

Continuous SPLITT fractionation of starch particles

The fractionation of starch granules was investigated using a SPLITT (split flow-thin) cell, a relatively new system for fast, continuous binary separations. The effect of such basic separation parameters as carrier composition, relative flow-rates and sample concentration on the SPLITT cell performance were exploited. The obtained starch fractions were checked by both optical microscopy and sedimentation / steric field flow fractionation (Sd/StFFF). The sedimentation field flow fractionation technique was employed for the starch sample using the density compensation procedure