Search results for " disposal"
showing 10 items of 1293 documents
A comparative economic analysis of torrefied pellet production based on state-of-the-art pellets
2017
Abstract Torrefied pellets have fuel properties superior to those of conventional wood pellets and potentially allow greater rates of co-firing and thus larger reductions in net CO 2 emissions. Despite the growing amount of scientific output on torrefaction, the economic feasibility of torrefied pellet production is still a topic of considerable uncertainty. This is an obstacle for decision makers looking to implement sustainable energy policies. This paper compares the economics of torrefied pellets to conventional wood pellets. Working backwards from demonstrated pellet properties, this work attempts to answer the following question: Based on state-of-the-art torrefied pellets, what would…
Carbon sequestration potential and soil characteristics of various land use systems in arid region
2019
Abstract Soils contain one of the largest carbon (C) pools in the biosphere with the greatest potential of C sequestration to mitigate climate change impacts. The present study aimed at comparing C sequestration potential of various land use systems including forestlands, croplands, agroforests, and orchards in the arid region of Pakistan. Soil samples from the layers of 0–20, 20–40, 40–60, and 60–80 cm depths were collected and analysed for soil physico-chemical properties namely texture, pH, EC, NPK-soil, organic matter (SOM), and soil organic C (SOC). Additionally, the above and below ground plant biomass and C contents were estimated. Results revealed that the highest C sequestration po…
Toxicity of waste gasification bottom ash leachate
2011
Abstract Toxicity of waste gasification bottom ash leachate from landfill lysimeters (112 m3) was studied over three years. The leachate of grate incineration bottom ash from a parallel setup was used as reference material. Three aquatic organisms (bioluminescent bacteria, green algae and water flea) were used to study acute toxicity. In addition, an ethoxyresorufin-O-deethylase (EROD) assay was performed with mouse hepatoma cells to indicate the presence of organic contaminants. Concentrations of 14 elements and 15 PAH compounds were determined to characterise leachate. Gasification ash leachate had a high pH (9.2–12.4) and assays with and without pH adjustment to neutral were used. Gasifi…
Total oxidation of naphthalene with high selectivity using a ceria catalyst prepared by a combustion method employing ethylene glycol.
2009
Abstract During the catalytic combustion of naphthalene, compounds other than CO 2 are often obtained. These products, as polymerized polycyclic aromatic hydrocarbons, oxygenated aromatic compounds and benzene derivate compounds, are usually more toxic than naphthalene. At the present work it is shown a nanocrystalline cerium oxide prepared by a combustion method employing a proper ethylene glycol concentration that exhibits very high activity in the decomposition of naphthalene in the presence of air and, most importantly, a selectivity value towards CO 2 of 100% for any range of conversions and/or temperatures used. In addition, it has been demonstrated that the amount of ethylene glycol …
Observations on mucus aggregates along Sicilian coasts during 1991–1992
1995
Abstract The results of some observations on gelatinous material accumulating on the sea ground and free floating in the water column along Sicilian coasts are reported. The phenomenon showed different development patterns moving from the Tyrrherian to the Jonian coast and to the Sicilian Channel. Moreover, in 1991, mucus aggregates in the Tyrrhenian sea showed a similar structure, behaviour and origin to those observed in the Adriatic sea, whereas, in 1992, only a massive growth of metaphytic threadlike algae, more or less producing gelatinous sheaths, occurred.
Use of semipermeable membrane devices for assessment of air quality in Tangier (Morocco)
2009
Semipermeable membrane devices (SPMDs) have been used for the evaluation of the contamination of air in both the urban and the industrial area in Tangier (Morocco). Benzene, toluene, ethylbenzene a...
Determination of mineral and trace element concentrations in pine needles by ICP-OES: evaluation of different sample pre-treatment methods
2008
In the present study, the determination of mineral and trace elements (Al, B, Ca, Cu, Fe, K, Mg, Mn, Na, P and Zn) from pine needles using three sample pre-treatment methods followed by inductively coupled plasma optical emission spectrometry, was examined. Sample pre-treatment methods tested were microwave digestion, ultrasound-assisted digestion and dry ashing. The new ultrasound-assisted digestion method was optimised by the analysis of the standard reference material (SRM) 1575a (pine needles) sample. The speed of dry ashing method was significantly increased by ultrasound dissolution after ashing. All the ICP-OES measurements were performed in robust plasma conditions which were tested…
Anwendung der Glas Carbon Elektrode für die Quecksilberbestimmung in Flußwasser mittels der Differential-Puls inversen Voltammetrie (DPAW)
1979
Abstract The Glassy Carbon Electrode was used for Mercury determination in “synthetic solutions” as well as in river water by stripping Voltammetry. Best results were obtained with a supporting electrolyte of the chemical composition 0.1m KSCN, 0.025 n HCl and 20ng/mlCu2+. The optimal pH was found to be 2.8 and the optimal deposition potential-1.0 volt. It is possible to determine at to 1.5ppb Hg2+ in river watersamples. Es wurde die Glas Carbon Elektrode benutzt, urn Quecksilber sowohl in “synthetischen Losungen” als auch in Fluswasser invers-voltammetrisch zu bestimmen. Fur die Bestimmung hat sich ein Grundelektrolyt der Zusammensetzung 0.1m KSCN, 0.025 n HCl und 20ng/ml Cu2+ gut bewahrt.…
Reactions of Carbonyl Compounds in Basic Solutions. Part 351: The Alkaline Hydrolysis and Reactivity – Structure – Spectra Correlations of (Z)-4-(Sub…
2002
The kinetics of the alkaline hydrolysis and the configuration, conformation and electronic structure were studied using IR, NMR spectroscopy, X-ray analysis and AM1 theoretical calculations for a series of (Z)-4-(substituted benzylidene)-2-phenyl-4H-oxazol-5-ones (1) and compared with analogous results reported for (E)-4-benzylidene-2-phenyl-4H-furan-5-ones (5) and related compounds.
Preparation and characterization of organofunctionalized bentonite clay bearing aminophosphonic groups in heavy metal uptake
2019
Abstract Bentonite (Bnt) with covalently immobilized N-propylaminodi(methylenephosphonic) groups (Bnt-ADPA) was obtained through a two-step synthesis including aminosilanization and phosphorylation of resulting aminobentonite through Moedritzer-Irani reaction. The grafting of an aminosilane layer in the interplanar space of the bentonite was investigated by XRD, and the presence of N and P-containing groups was confirmed by FTIR, 31P and 29Si MAS NMR. The immobilization of the organic functional groups increased the interplanar distance in bentonite matrix at 52% that essentially improved filtration properties compared to raw bentonite. The number of surface acid groups was evaluated to 0.8…