Search results for "Ozone"
showing 10 items of 300 documents
Revision of the New World Species of Peritropis Uhler (Heteroptera: Miridae: Cylapinae)
2012
The New World species of the genus Peritropis are revised, and 17 new species are described: P. amazonica, P. amphicyrta, P. carpinteroi, P. carvalhoi, P. conspersa, P. cornata, P. gorczycai, P. guarani, P. izyai, P. marmorea, P. nicaraguensis. P. plaumanni, P. schaffneri, P. scutellata, P. stobieckii, P. turrialba and P. venezuelaensis. All previously known species from the New World (P. husseyi Knight, P. saldaeformis Uhler, and P. tuberculata McAtee and Malloch) are redescribed, except P. unicolor Carvalho and Rosas for which an English translation of the original description is provided. Illustrations of the male genitalia, a color photograph of the adult of each species, scanning elect…
Economic valuation of environmental benefits of removing pharmaceutical and personal care products from WWTP effluents by ozonation.
2013
Continuous release of pharmaceutical and personal care products (PPCPs) present in effluents from wastewater treatment plants (WWTPs) is nowadays leading to the adoption of specific measures within the framework of the Directive 2000/60/EC (Water Framework Directive). The ozonation process, normally employed for drinking water production, has also proven its potential to eliminate PPCPs from secondary effluents in spite of their low concentrations. However, there is a significant drawback related with the costs associated with its implementation. This lack of studies is especially pronounced regarding the economic valuation of the environmental benefits associated to avoid the discharge of …
Screening of physical–chemical methods for removal of organic material, nitrogen and toxicity from low strength landfill leachates
2002
Physical-chemical methods have been suggested for the treatment of low strength municipal landfill leachates. Therefore, applicability of nanofiltration and air stripping were screened in laboratory-scale for the removal of organic matter, ammonia, and toxicity from low strength leachates (NH4-N 74-220 mg/l, chemical oxygen demand (COD) 190-920 mg O2/l, EC50 = 2-17% for Raphidocelis subcapitata). Ozonation was studied as well, but with the emphasis on enhancing biodegradability of leachates. Nanofiltration (25 degrees C) removed 52-66% of COD and 27-50% of ammonia, the latter indicating that ammonia may in part have been present as ammonium salt complexes. Biological pretreatment enhanced t…
Heterogeneous catalytic degradation of phenolic substrates: catalysts activity
2009
This review article explored the catalytic degradation of phenol and some phenols derivates by means of advanced oxidation processes (AOPs). Among them, only the heterogeneous catalyzed processes based on catalytic wet peroxide oxidation. catalytic ozonation and catalytic wet oxidation were reviewed. Also selected recent examples about heterogeneous photocatalytic AOPs; will be presented. In details, the present review contains: (i) data concerning catalytic wet peroxide oxidation of phenolic compounds over metal-exchanged zeolites, hydrotalcites, metal-exchanged clays and resins. (ii) Use of cobalt-based catalysts, hydrotalcite-like compounds, active carbons in the catalytic ozonation proc…
Comparison between ozonation and the OSA process: analysis of excess sludge reduction and biomass activity in two different pilot plants
2012
The excess biomass produced during biological treatment of municipal wastewater represents a major issue worldwide, as its disposal implies environmental, economic and social impacts. Therefore, there has been a growing interest in developing technologies to reduce sludge production. The main proposed strategies can be categorized according to the place inside the wastewater treatment plant (WWTP) where the reduction takes place. In particular, sludge minimization can be achieved in the wastewater line as well as in the sludge line. This paper presents the results of two pilot scale systems, to evaluate their feasibility for sludge reduction and to understand their effect on biomass activit…
A worrisome failure of the CC2 coupled-cluster method when applied to ozone
2010
Abstract The approximate coupled-cluster singles and doubles model CC2 is widely used for calculations of excited states in large molecules. We demonstrate a surprising failure of the CC2 geometry optimization of ozone, whereby the CC2 method predicts a barrierless, exothermic, and symmetric dissociation to three oxygen atoms. This is particularly astonishing since both second-order Moller–Plesset perturbation theory and coupled-cluster singles and doubles give reasonable equilibrium structures. We find that [ [ H , T 1 ] , T 1 ] leads to an unbalanced treatment of T 1 and T 2 in the CC2 equations. Results presented here suggest that considerable caution should be exercised when applying th…
High-resolution dynamics of Early Jurassic marine extinctions: the case of Pliensbachian–Toarcian ammonites (Cephalopoda).
2010
Abstract: The Pliensbachian–Toarcian interval was marked by major environmental disturbances and by a second-order mass extinction. Here, we reappraise the taxonomic, spatiotemporal and selective dynamics of extinctions over the whole interval, by analysing a high-resolution dataset of 772 ammonite species from NW Tethyan and Arctic domains. On average, 40–65% of ammonite species disappeared during each subchronozone, but higher extinction pulses (reaching 70–90%) prevailed from the Margaritatus to the Dispansum Chronozone. The main extinctions, corresponding to the Gibbosus, Pliensbachian–Toarcian boundary, Semicelatum, Bifrons–Variabilis, and Dispansum events, differed in their dynamics, …
Water Depollution by Advanced Oxidation Technologies
2020
This chapter deals with water treatments by advanced oxidation processes (AOPs) based on chemical and photochemical reactions. The most used processes are described, and for each of them, the main reaction mechanisms, principles, advantages, drawbacks, performances and formation of by-products, coupled with technologies and their applications to waters and wastewater depollution, have been analysed, supporting the main results of studies published in the pertinent literature.
OZONE THERAPY: TERATOGENIC STUDY OF OZONE. POSSIBLE INDICATIONS IN OBSTETRICS AND GYNECOLOGY
2018
Ozone is a powerful oxidant, surpassed, in this regard, only by fluorine. Its doubtless strong reactivity has contributed to establish the dogma that ozone is always toxic and its medical application must be proscribed. However, ozone therapy has been used for therapeutic purposes since the beginning of the last century and its use is increasingly demanded nowadays. For proper enlightenment and guidance of the person interested in the use of ozone for medical purposes, scientific documentation on the safety/toxicity profile of this acclaimed procedure becomes necessary. Taking into account that the National Health Regulatory Agencies require of documentation with scientific trials for sanit…
Does the EMU Need a Fiscal Transfer Mechanism?
2004
Summary: The aim of this paper is to investigate how the birth of a central fiscal authority or the creation of a fiscal transfer mechanism could improve the action of fiscal policy in terms of stabilization in the EMU. In particular, the paper examines the theoretical reasons to support this conclusion and provides empirical evidence that shows how the EMU is not able to face asymmetric and symmetric idiosyncratic shocks. Zusammenfassung: Die zentrale Frage des Aufsatzes lautet: Ob und wie kann eine zentrale Fiskalbehorde oder ein fiskalischer Transfermechanismus die fiskalpolitische Stabilisierung in der EWU verbessern? Dazu werden theoretische Argumente und empirische Evidenz prasentiert…