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Rodica Chiriac Jean Carré Yves Perrodin Hervé Vaillant Santiago Gasso Philippe Miele 《Atmospheric environment (Oxford, England : 1994)》2009,43(11):1926-1931
The dispersion of VOCs emitted by a municipal solid waste landfill was studied for a period of over one year. Sixteen VOCs were monitored: linear alkanes from C7 to C11, BTEX, trimethylbenzene, trichlorethylene, tetrachlorethylene, α and β-pinenes, limonene. The analytical procedure was first comprised of static long-term sampling of about 2 months using radial diffusion Radiello tubes containing activated carbon, followed by extraction by solvent (i.e. CS2) and GC/MS analysis. The results were initially analysed on the basis of the total concentration of the quantified VOCs, then by examining the concentrations of certain selected compounds. The influence of different parameters such as operating conditions, meteorological conditions and site morphology was highlighted on the basis of total VOC concentrations. In order to study the VOC's dispersion more closely, 5 compounds were chosen: toluene, benzene, limonene, and the sum trichlorethylene + tetrachlorethylene, as a “marker”, to verify the origin of the VOCs emitted. The results showed that the main source of VOCs is the open cell and lead to different hypotheses on interferences from neighbouring sources and to the proposal of solutions to limit the emission of VOCs and their dispersion. To our knowledge, this type of study has not been accomplished until this day. 相似文献
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Constantin Bobirică David T. Long Matthew J. Parsons Rodica Stănescu Thomas C. Voice 《Journal of Material Cycles and Waste Management》2018,20(1):59-70
The leaching of lead from cement-based solidified waste forms mixed at different water/cement ratios was studied by conducting equilibrium and semi-dynamic leaching tests using deionized water and sodium chloride solutions. The results suggest that leaching of the primary constituents of the cement (calcium, silicon and sulfate) is controlled by solubility equilibria, with increased leaching into chloride solutions due to ionic strength effects. The original porosity of the waste forms increased with water/cement ratio and chloride solutions further increased it as a result of decalcification. Lead leaching was generally low, and appears to be a transport-controlled process, such that leaching correlates positively with porosity. 相似文献
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Nita Tudorachi Rodica Lipsa Cornelia Vasile Fanica Mustata 《Journal of Polymers and the Environment》2013,21(4):1064-1071
The synthesis and characterization of poly(lactic acid)-co-aspartic acid copolymers (PLA-co-Asp) were presented. Subsequently, the synthesized PLA-co-Asp copolymers were tested as biodegradable carriers in drug delivery systems. PLA-co-Asp copolymers were synthesized by solution polycondensation procedure, using different molar ratios PLA/l-aspartic acid (2.33/1, 1/1, 1/2.33), manganese acetate and phosphoric acid as catalysts and N,N′-dimethyl formamide (DMF)/toluene as solvent mixture. The copolymers were characterized by FT-IR and 1H-NMR spectroscopy, gel permeation chromatography (GPC), DSC and TG-DTG analyses. Diclofenac sodium, a non steroidal anti-inflammatory drug was subsequently loaded into PLA-co-Asp copolymers. The in vitro drug release experiments were done by dialysis of the copolymer/drug systems, in phosphate buffer solution (pH = 7.4, at 37 °C) and monitored by UV spectroscopy. 相似文献
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Corona P Agrimi M Baffetta F Barbati A Chiriacò MV Fattorini L Pompei E Valentini R Mattioli W 《Environmental monitoring and assessment》2012,184(3):1409-1422
Urban areas are continuously expanding today, extending their influence on an increasingly large proportion of woods and trees
located in or nearby urban and urbanizing areas, the so-called urban forests. Although these forests have the potential for
significantly improving the quality the urban environment and the well-being of the urban population, data to quantify the
extent and characteristics of urban forests are still lacking or fragmentary on a large scale. In this regard, an expansion
of the domain of multipurpose forest inventories like National Forest Inventories (NFIs) towards urban forests would be required.
To this end, it would be convenient to exploit the same sampling scheme applied in NFIs to assess the basic features of urban
forests. This paper considers approximately unbiased estimators of abundance and coverage of urban forests, together with
estimators of the corresponding variances, which can be achieved from the first phase of most large-scale forest inventories.
A simulation study is carried out in order to check the performance of the considered estimators under various situations
involving the spatial distribution of the urban forests over the study area. An application is worked out on the data from
the Italian NFI. 相似文献
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Samomssa Inna Nono Yvette Jiokap Cârâc Geta Gurău Gheorghe Dinică Mihaela Rodica Kamga Richard 《Journal of Material Cycles and Waste Management》2021,23(5):1905-1917
Journal of Material Cycles and Waste Management - Mechanical properties enable to handle storage and transport of fuel briquette. Binder is key element of these mechanical properties. Biobinder is... 相似文献
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Chiriac R De Araujos Morais J Carre J Bayard R Chovelon JM Gourdon R 《Waste management (New York, N.Y.)》2011,31(11):2294-2301
The emission of volatile organic compounds (VOCs) from municipal solid waste stored in a pilot-scale cell containing 6.4 tonnes of waste (storage facility which is left open during the first period (40 days) and then closed with recirculation of leachates during a second period (100 days)) was followed by dynamic sampling on activated carbon and analysed by GC–MS after solvent extraction. This was done in order to know the VOC emissions before the installation of a methanogenesis process for the entire waste mass. The results, expressed in reference to toluene, were exploited during the whole study on all the analyzable VOCs: alcohols, ketones and esters, alkanes, benzenic and cyclic compounds, chlorinated compounds, terpene, and organic sulphides.The results of this study on the pilot-scale cell are then compared with those concerning three biogases from a municipal waste landfill: biogas (1) coming from waste cells being filled or recently closed, biogas (2) from all the waste storage cells on site, and biogas (3) which is a residual gas from old storage cells without aspiration of the gas. The analysis of the results obtained revealed: (i) a high emission of VOCs, principally alcohols, ketones and esters during the acidogenesis; (ii) a decrease in the alkane content and an increase in the terpene content were observed in the VOCs emitted during the production of methane; (iii) the production of heavier alkanes and an increase in the average number of carbon atoms per molecule of alkane with the progression of the stabilisation/maturation process were also observed.Previous studies have concentrated almost on the analysis of biogases from landfills. Our research aimed at gaining a more complete understanding of the decomposition/degradation of municipal solid waste by measuring the VOCs emitted from the very start of the landfill process i.e. during the acidogenesis and acetogenesis phases. 相似文献
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This study estimates the human cost of failures in the CCS industry in 2050, using the actuarial approach. The range of expected fatalities is assessed integrating all steps of the CCS chain: additional coal production, coal transportation, carbon capture, transport, injection and storage, based on empirical evidence from technical or social analogues. The main finding is that a few hundred fatalities per year should be expected if the technology is used to avoid emitting 3.67 GtCO2 year−1 in 2050 at baseload coal power plants. The large majority of fatalities are attributable to mining and delivering more coal. These risks compare to today's industrial hazards: technical, knowable and occupational dangers for which there are socially acceptable non-zero risk levels. Some contemporary European societies tolerate about one fatality per thousand years around industrial installations. If storage sites perform like that, then expected fatalities per year due to leakage should have a minor contribution in the total expected fatalities per year: less than one. But to statistically validate such a safety level, reliability theory and the technology roadmap suggest that CO2 storage demonstration projects over the next 20 years have to cause exactly zero fatality. 相似文献
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There is a wide range of applications where calcium phosphate and hydroxyapatite (HA) are used as biomaterials, e.g. as synthetic
bone grafts, coating on metal prostheses (like hip endoprostheses or dental implants) and drug carriers. In the study, the
design and synthesis of composites based on poly(vinyl alcohol-co-lactic acid)/hydroxyapatite (PVA-co-LA/HA) with potential
for biomedical applications, they are presented. The hydroxyapatite particles were surface-grafted with l(+)-lactic acid in the presence of manganese acetate as catalyst, resulting in modified hydroxyapatite (HAm) with improved capacity of bonding, respectively for the preparation of the composite based on PVA-co-LA/HAm. FT-IR spectra further confirmed the existence of PLA polymer on the surface of HA particles. In synthesis of PVA-co-LA copolymer
the different molar ratios PVA/LA (2/1, 1/1, 1/2), toluene/water: 1/2 (as azeotrope solvent mixture) and manganese acetate
as catalyst, were used. The composite materials were synthesized in situ with 10 wt% HA, and respectively HAm (reported to PVA and lactic acid components). The composite materials were characterized by FTIR spectroscopy, thermal analyses
(DSC, DTG), 1H-NMR spectroscopy, particle size distribution and zeta potential. 相似文献