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Electroplating rinse solutions contain considerable amounts of multivalent valuable or toxic metal ions. The attempt to recover them was made using the Donnan dialysis (DD) technique, applying a cation-exchange polymer membrane. Laboratory experiments dealing with processing two different solutions containing Zn(ll) [A], or Zn(II), Cu(II), Ni (II), Cr(III) and Fe(III) [B] were carried out. The results demonstrated DD to be efficient for recovering Zn(II) (soln.A) and other multivalent metals (soln.B) in the sequence Ni, Cu>Fe>Zn>Cr. Recovery factors amount to 80-90% and 74-94% for A and B solutions, respectively. The optimum concentration of sulfuric acid in the strip solution ranges from 0.25 to 0.5 M.
The present work is a continuation of studies on the use of ion-exchanging properties of smectite raw material from Męcinka mine to the recovery of chromium from waste water. In this work the smectite ion-exchange column was used for removal of other heavy metals: Zn (II), Cd (II),Pb(II).Theeffect of ion-exchangeZn (II),Cd (II),Pb(II)from model solutions prepared out of nitrate salts of these metals was examined under dynamic conditions. The efficiency of ion-exchange column with smectite bed was determined by measuring in the column efflux till the moment when the concentration of metals in efflux is equal to concentration in influx. For measurement of concentration of metals the voltamperometric method was used. The ion-exchanging column was determined by stating the following parameters: sorption capacity of exchanger, volume of solution till the moment of column breakthrough (Vmax) and column dynamics, which meansthe relative concentration of metal ions c/c0 in theefflux as a function of efflux volume. Out of the model waste water containing three heavy metals, the best eliminated is Pb (II) and subsequently Zn (II). The efflux volume classified to the 1st and 2nd category of water cleanness amounts to about 1/3 Vmax. Worse results are observed for ions Cd (II), which have the least ion exchange ability. The obtained results of studies on removal of ions of heavy metals: Zn (II), Cd (II), Pb (II) out of model waste water confirm, similar to the Cr (III) studies, the possibility of application of the raw smectite adsorbent as the column packing within the process of removal of heavy metals.
Background. Polybrominated diphenyl ethers (PBDEs) belong to group of so-called persistent organic pollutants (POPs). These compounds occur in nearly all elements of the environment, including household dust which constitutes one of a major route for human exposure. Their main adverse effects on human health are associated mainly with endocrine disruption – they interfere with thyroid function exhibit anti-androgenic action. Objectives. To develop and validate analytical method for determination of BDE-47, BDE-99, BDE-153, and BDE-209 congeners in household dust. Material and methods. Household dust was sampled in residences from Warsaw and the surrounding areas. An automated Soxhlet extraction of samples was then performed and PBDE congeners were subsequently measured in cleaned-up extracts by GC-μECD. The identity of quantified compounds was confirmed by GC/MS. Results. Household dust samples were fortified at levels of 2.88, and 28.8 ng g-1 for BDE-47, BDE-999, and BDE-153, and for BDE-209 at levels of 101.2, and 540 ng g-1. Recoveries ranged between 72 – 106%. The relative standard deviations (RSD) were less than 16% for all PBDE congeners analysed. The relative error determined on the basis of multiple analyses of certified reference material ranged from 1.07 – 20.41%. The method’s relative expanded uncertainty varied between 16 – 21%. Conclusion. The presented method was successfully validated and can be used to measure concentrations of BDE-47, BDE-99, BDE-153 and BDE-209 congeners in household dust.
The process of the isolation of malathion from water matrix has been optimized from the point of recovery. Solid phase extraction (SPE) columns with different material packings have been used to study the dependence of recovery on adsorbent type, structure and character. Solid membrane EMPORE with C-18 groups has also been used for this investigation. Comparison of extraction efficiency obtained for SPE column and extraction disc has been done.
The major purpose of this paper is (1) to find out the criteria for voluntary recycling by a for-profit recycler and for state intervention with recycling for a particular recyclable waste, (2) to present models to determine the private and social optimal recycling rates respectively, and (3) to determine optimal implementation policy by providing economic incentives to motivate recycling. The results of the analysis conclude that (1) an increase in conversion efficiency, the price of secondary material, and carbon taxes will lead to an increase in recycling rates, (2) the subsidy based on secondary material recovered will result in a higher recycling rate and will improve recovery technology more than a subsidy for recyclable wastes collected and sorted.
The flotation method elaborated for recovery of Toxocara and other geohelminth eggs from soil is described. Soil samples of about 500 ml volume are picked from 3-cm superficial layer of the ground. In the laboratory, 40 g of dry and sifted material is analysed according to following procedure: 1 h standing, 20 minutes shaking and 3 minutes centrifugation (1500 rpm) in 5% sodium hydroxide (NaOH), then centrifugation, like above, with H₂O for washing the sample and next with the saturated sodium nitrate (NaNO₃) for flotation the eggs. Specimen is prepared by placing a cover slip on the positive meniscus of the flotation liquid.
The Spathian (late Early Triassic) Virgin Formation of south−western Utah (USA) yields a comparatively diverse benthic fauna that flourished ~2 Ma after the end−Permian mass extinction. In this study, we present quantitative palaeoecological data, which are analysed in the context of depositional environments. This integrated approach helps to discriminate between effects of the end−Permian mass extinction event and local environmental factors on alpha diversity and ecological structure of the Virgin Fauna. Shallow subtidal environments yield the highest species richness and lowest dominance val− ues as recorded in two benthic associations, the Eumorphotis ericiusAssociation and the Protogusarella smithi Association, both ofwhich contain 20 benthic species (bivalves, gastropods, brachiopods, echinoderms, and porifers). Tidal inlet deposits yield a low diverse fauna (Piarorhynchella triassica Association) with a very high dominance of filter feeders adapted to high energy conditions.Another comparably low diverse fauna is recorded by the Bakevellia exporrecta Association, which occurs in deposits of the offshore transition zone,most likely reflecting unconsolidated substrates. A single sample contain− ing five bivalve species (Bakevellia costata Assemblage) is recorded from a marginal−marine setting. The Virgin fauna yields a bulk diversity of 30 benthic species (22 genera) of body fossils and 14 ichnogenera and, thus, represents the most di− verse marine bottom fauna known so far from the Early Triassic. Our results suggest that oceanographic conditions during the early Spathian enabled ecosystems to rediversify without major abiotic limitations. However, taxonomical differentia− tion between habitats was still low, indicating a time lag between increasing within−habitat diversity (alpha diversity) and the onset of taxonomical differentiation between habitats (beta diversity). We suggest that taxonomical habitat differentia− tion after mass extinction events starts only when within−habitat competition exceeds a certain threshold, which was not yet reached in the Spathian of the investigated area. This interpretation is an alternative to previous suggestions that the preva− lence of generalistic taxa in the aftermath of mass extinction events reflects protracted environmental stress. The onset of in− creasing beta diversity is a potential criterion for distinguishing two major recovery phases, the first ending with habitat satu− ration and the second ending with the completion of ecosystem differentiation.
 Inflammation is a non-specific immune response to infection, irritation or other injury, the key features being redness, warmth, swelling and pain. A number of mediators are released which alter the resistance of mucosa to injury induced by noxious substances. Oxidative stress is a unifying mechanism of injury in many types of disease processes, including gastrointestinal diseases. It has been defined as an imbalance in the activity of pro and antioxidants. Pro-oxidants favour free radical formation while antioxidants inhibit or retard the same. A number of markers of oxidative stress have been identified. This review provides an overview of various mediators of inflammation and oxidative stress, and diverse approaches for prevention and treatment of gastrointestinal inflammation.
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Carbon emission control measures

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This paper seeks to share the experience of the Ultra Low CO2 Steelmaking programme (ULCOS) established in 2002 by a number of EU members on how to cut down CO2 emission by at least 50 % of the present volume of emission. Global environmental challenge today is the issue of climate change resulting in devastating effects such as flooding in many countries of the world. One of the major causes is the CO2 emission from different industries including iron and steel industries. The total global CO2 emission was put at 29Gt in 2007 and projected to be 37Gt by the 2020. Out of this volume the steel industry accounts for 3-4 % and this call for concern from stakeholders to come up with measures to reduce or control the emission of the green house gas. These measures are necessary considering the growth of the iron and steel industry in the last 50 years. Important items considered include among others carbon emission and recovery, carbon capture and storage and new iron and steel making processes and their potential for CO2 reduction.
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