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81.
A. Ben Hassen-Trabelsi T. Kraiem S. Naoui H. Belayouni 《Waste management (New York, N.Y.)》2014,34(1):210-218
Several animal (lamb, poultry and swine) fatty wastes were pyrolyzed under nitrogen, in a laboratory scale fixed-bed reactor and the main products (liquid bio-oil, solid bio-char and syngas) were obtained. The purpose of this study is to produce and characterize bio-oil and bio-char obtained from pyrolysis of animal fatty wastes. The maximum production of bio-oil was achieved at a pyrolysis temperature of 500 °C and a heating rate of 5 °C/min. The chemical (GC–MS analyses) and spectroscopic analyses (FTIR analyses) of bio-oil showed that it is a complex mixture consisting of different classes of organic compounds, i.e., hydrocarbons (alkanes, alkenes, cyclic compounds…etc.), carboxylic acids, aldehydes, ketones, esters,…etc. According to fuel properties, produced bio-oils showed good properties, suitable for its use as an engine fuel or as a potential source for synthetic fuels and chemical feedstock. Obtained bio-chars had low carbon content and high ash content which make them unattractive for as renewable source energy. 相似文献
82.
83.
Nabil Tlili Georges Grévillot Cécile Vallières 《International Journal of Greenhouse Gas Control》2009,3(5):519-527
Experimental work is performed with a 5A zeolite on a small laboratory column with heating from the wall. Carbon dioxide adsorption occurs at atmospheric pressure and different CO2 concentrations in nitrogen. Comparisons of different methods of desorption by heating, purge and/or vacuum are studied. Desorption by heating only leads to almost pure CO2 (around 99% purity) and a recovery nearly linear to the heating temperature, ranging from 45% at 130 °C to 79% at 210 °C. Recovery can be subsequently increased with a nitrogen purge to more than 98% but the recovered carbon dioxide is diluted due to the dispersive character of the desorption wave and the operation time is long. Increasing the flow rate decreases the desorption time but has no effect on the purity because the total purge volume remains about the same. Substitution of the purge step with a vacuum step leads to pure CO2 and almost total recovery. Desorption under vacuum only without heating leads to pure CO2 (around 99% purity) but limited recovery (85% in the present work).Desorption under vacuum seems to be more simple for large-scale applications. When using a water liquid ring pump, the temperature of the ring must be kept as low as possible to provide a high operating capacity. 相似文献
84.
Ben Adams Mohamed Abdelwahab Manjusri Misra Amar K. Mohanty 《Journal of Polymers and the Environment》2018,26(6):2360-2373
This paper investigates the effects of the incorporation of lignin and small quantities of epoxidized natural rubber (ENR) as an impact modifying agent on blends of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and poly(ε-caprolactone) (PCL). The addition of lignin resulted in a slight improvement of flexural strength and modulus of the ternary blending system. Incorporation of ENR into the blend resulted in an increase in notched Izod impact strength from 40 to 135% depending on the concentration of ENR. The addition of lignin into the blend resulted in an improvement of thermal stability of the ternary blend system. Morphological analysis showed a good dispersion of PHBV phases and lignin within the PCL matrix. Rheological characterization revealed that the presence of lignin resulted in increased storage modulus of the bioblend. 相似文献
85.
Ben A. Minteer Elizabeth A. Corley Robert E. Manning 《Journal of Agricultural and Environmental Ethics》2004,17(2):131-156
Many nonanthropocentric environmental ethicists subscribe to a ``principle-ist' approach to moral argument, whereby specific natural resource and environmental policy judgments are deduced from the prior articulation of a general moral principle. More often than not, this principle is one requiring the promotion of the intrinsic value of nonhuman nature. Yet there are several problems with this method of moral reasoning, including the short-circuiting of reflective inquiry and the disregard of the complex nature of specific environmental problems and policy arguments. In the present paper, we advance an alternative, pragmatic contextualist approach to environmental ethics, one grounded in the moral theory of John Dewey. We present the results of an empirical study of public environmental ethics and natural resource management attitudes to support our position, and we conclude with a few recommendations for future inquiry in the field of environmental ethics. 相似文献
86.
René van der Wal Cheng Zeng Danny Heptinstall Kapila Ponnamperuma Chris Mellish Stuart Ben Advaith Siddharthan 《Ambio》2015,44(4):612-623
Analysis of satellite-telemetry data mostly occurs long after it has been collected, due to the time and effort needed to collate and interpret such material. Delayed reporting reduces the usefulness of such data for nature conservation where timely information about animal movements is required. To counter this problem, we present a novel approach which combines automated analysis of satellite-telemetry data with rapid communication of insights derived from such data. A relatively simple algorithm (based on radial and angular velocity calculated from fixes) allowed instantaneous detection of excursions away from settlement areas and automated calculation of home ranges on the remaining data. Automating the detection of both excursions and home-range calculations enabled us to disseminate ecological insights from satellite-tag data instantaneously through a dedicated web portal. The automated analysis, interpretation, and communication of satellite-tag and other ecological data offer clear benefits to nature conservation research and practice. 相似文献
87.
单室MFC型生物毒性传感器对重金属离子的检测研究 总被引:2,自引:0,他引:2
构建了单室微生物燃料电池(air-cathode microbial fuel cell,ACMFC)型生物毒性传感器,以含重金属离子(Cd2+、Cu2+)人工配水为检测对象,分析了有毒物质对检测仪的抑制率与有毒物质浓度的线性关系.结果表明,①单室MFC型生物毒性传感器结构简单,操作方便,灵敏度较高,可用于水体重金属离子(Cd2+、Cu2+)生物毒性的快速检测;②在实验条件下,该生物毒性传感器检测时间4h,清洗时间2~10min,恢复时间4h;③检测结果显示,实验室自配Cd2+、Cu2+及其混合液IC20值分别为0.6、0.8和0.25mg/L,有毒物质浓度与MFC产电量的抑制率呈显著正相关,相关系数分别为0.9960、0.9744和0.9907. 相似文献
88.
Lotfi Rabaoui Sabiha Tlig Zouari Stelios Katsanevakis Oum Kalthoum Ben Hassine 《Marine Biology》2007,152(3):537-548
The variability in absolute and relative growth of Pinna nobilis along the Tunisian coastline was investigated. Five populations of P. nobilis were sampled, three from northern and two from eastern Tunisia. The specimens were aged and ten morphometric characters were
measured on each individual. To test if differences existed in absolute and relative growth patterns among the different populations
an information theory approach was followed. For absolute growth, von Bertalanffy, Gompertz, the logistic and the power models
were fitted in combination with three assumptions regarding inter-population differences in absolute growth patterns: no differences,
differences among all five populations or just between northern and eastern populations. The assumption of common absolute
growth parameters among all five populations had the greatest support by the data, whereas the assumption of different growth
patterns among all five populations had no support. Von Bertalanffy growth model and the power model were both equally supported
by the data (while Gompertz had considerably less support and the logistic model had no support), and thus it may not be definitely
concluded whether P. nobilis grows asymptotically or not. The P. nobilis populations of the Tunisian coastline had a slow growth and up to an age of ∼ 9 years their shells were smaller than from
all other reported populations in the Mediterranean. For relative growth, apart from the classical allometric model Y = aX
b
, relating the size of a part of a body Y to another reference dimension X, more complicated models were used in combination with the three abovementioned assumptions regarding inter-population differences.
Those models, of the form logY = f (logX), either assumed breakpoints in the relative growth trajectories or non-linearities. For most morphometric characters, the
classical allometric model had no support by the data and more complicated models were necessary. In most cases, different
relative growth either among all five populations or between the northern and eastern population groups was supported by the
data. Further investigation is needed to relate the morphological differences observed among different populations of P. nobilis to environmental factors. 相似文献
89.
László Z. Garamszegi Thorsten J. S. Balsby Ben D. Bell Marta Borowiec Bruce E. Byers Tudor Draganoiu Marcel Eens Wolfgang Forstmeier Paolo Galeotti Diego Gil Leen Gorissen Poul Hansen Helene M. Lampe Stefan Leitner Jan Lontkowski Laurent Nagle Erwin Nemeth Rianne Pinxten Jean-Marc Rossi Nicola Saino Aurélie Tanvez Russell Titus János Török Els Van Duyse Anders P. Møller 《Behavioral ecology and sociobiology》2005,57(4):305-317
Repertoire size, the number of unique song or syllable types in the repertoire, is a widely used measure of song complexity in birds, but it is difficult to calculate this exactly in species with large repertoires. A new method of repertoire size estimation applies species richness estimation procedures from community ecology, but such capture-recapture approaches have not been much tested. Here, we establish standardized sampling schemes and estimation procedures using capture-recapture models for syllable repertoires from 18 bird species, and suggest how these may be used to tackle problems of repertoire estimation. Different models, with different assumptions regarding the heterogeneity of the use of syllable types, performed best for different species with different song organizations. For most species, models assuming heterogeneous probability of occurrence of syllables (so-called detection probability) were selected due to the presence of both rare and frequent syllables. Capture-recapture estimates of syllable repertoire size from our small sample did not differ significantly from previous estimates using larger samples of count data. However, the enumeration of syllables in 15 songs yielded significantly lower estimates than previous reports. Hence, heterogeneity in detection probability of syllables should be addressed when estimating repertoire size. This is neglected using simple enumeration procedures, but is taken into account when repertoire size is estimated by appropriate capture-recapture models adjusted for species-specific song organization characteristics. We suggest that such approaches, in combination with standardized sampling, should be applied in species with potentially large repertoire size. On the other hand, in species with small repertoire size and homogenous syllable usage, enumerations may be satisfactory. Although researchers often use repertoire size as a measure of song complexity, listeners to songs are unlikely to count entire repertoires and they may rely on other cues, such as syllable detection probability.Communicated by A. Cockburn 相似文献
90.
Sondes Melliti Ben Garali Inès Sahraoui Pablo de la Iglesia Mohamed Chalghaf Jorge Diogène Jamel Ksouri 《Chemistry and Ecology》2020,36(1):66-82
ABSTRACTThe seasonal variations in Pseudo-nitzschia species and domoic acid (DA) concentration were investigated, at three shellfish farms in SW coastal Mediterranean. In parallel, the toxicity of mussels was tested. Two distinct groups of species were enumerated according to morphology and size (Pseudo-nizschia delicatissima and P. seriata groups). DA was detected over a nine-week period from July to October 2012 in the Lagoon, with a maximum concentration recorded in July (12.71?ng?DA?L?1). DA was positively correlated with the presence of P. seriata-group and P. delicatissima-group and was mostly occurred during P limitation period in seawater. No DA was found in mussels that were collected during the period of DA absence in seawater. Our results suggest that temperature, salinity, inorganic and organic nutrients were significant for the seasonal dynamics of P. seriata and P. delicatissima groups, but that the P limitation was the most driving factor for DA production in these areas. The relative influence of environmental factors should be further studied to better understand the recent surfacing of massive blooms of toxigenic Pseudo-nitzschia in SW Mediterranean coast. 相似文献