The changes in the physical characteristics of unconditioned and conditioned anaerobic digested sludge （ADS） biosolids, such as capillary suction time （CST）, yield stress, average size and fractal dimensions, were...The changes in the physical characteristics of unconditioned and conditioned anaerobic digested sludge （ADS） biosolids, such as capillary suction time （CST）, yield stress, average size and fractal dimensions, were investigated through a CST test, transient and dynamic rheological test and image analysis. The results showed that the optimum polymer dose range was observed when CST or its reciprocal value was employed as an indicator. There were good correlations between the yield stresses determined from both a controlled shear stress test and a strain amplitude sweep test. The yield stress and storage modulus （G＇） increased as the polymer dose increased in most cases. A frequency sweep test revealed that polymer conditioning could extend the frequency sweep ranges for their elastic behaviors over viscous behaviors as well as the gel-like structure in the linear viscoelastic range. These results implied that more deformation energy was stored in this rigid structure, and that elastic behavior became increasingly dominant with the addition of the polymer in most cases, In addition, both the average sizes and two-dimensional fractal dimensions for conditioned ADS biosolids presented a similar up-climax-down variation trend as the polymer doses increased, whereas the critical polymer doses at the highest average sizes or two-dimensional fractal dimensions, were different. Correlation analysis revealed that the conditioned ADS dewaterability was not correlated with the yield stresses, while the average sizes or the two-dimensional fractal dimensions for conditioned ADS biosolids could be taken as the indication parameters for ADS dewaterability.展开更多
WUIma -which stands for Wildland-Urban Interface MAPping-is a software tool based on a GIS model （developped with Arcgis functions） designed to map wildland-urban interfaces at a large scale over a large area. The m...WUIma -which stands for Wildland-Urban Interface MAPping-is a software tool based on a GIS model （developped with Arcgis functions） designed to map wildland-urban interfaces at a large scale over a large area. The main outputs of WUImap are： （1） the map of twelve types of wildland-urban interfaces existing on the territory; （2） the map of four housing configuration （isolated, scattered, dense and very dense clustered housing） related to wildland-urban interfaces （WUI）. These maps are produced according to the method of WUI characterization combining housing configuration and horizontal structure of vegetation. Required inputs to map WUI are the layer of the residential house, the layer defining the fire sensitive area and the layer of the index of aggregation calculated on vegetation. The method of WUI characterization and mapping incorporated into WUImap has been evaluated and applied on real cases with good results. WUlmap has applicability as a decision support aid in a wide variety of land management ranging from fire management and fire prevention to analysis of WUI spread and land cover dynamic. The core method underlying the WUlrnap is summarized in the present paper.展开更多
This article describes a conductometric bi-layer based bienzyme biosensor for the detection of proteins as a marker of organic matter in rivers. Proteins were chosen to be used as indicators of urban pollution. The wo...This article describes a conductometric bi-layer based bienzyme biosensor for the detection of proteins as a marker of organic matter in rivers. Proteins were chosen to be used as indicators of urban pollution. The working mechanism of the bienzyme biosensor is based on the enzymatic hydrolysis of proteins into several fractions （peptides and amino acids）, which results in a local conductivity change depending of the concentration of proteins. In this work, we began with the optimization of biosensor response using bovine serum albumin （BSA） as standard protein. For this objective seven enzymatic biosensors were prepared： four enzymatic sensors with only one layer of enzyme （proteinase K, trypsin, pronase or protease X） and three other enzymatic sensors with two layers （first layer： membrane containing proteinase K; second layer： one of the three other enzymes： trypsin, pronase or protease X）. The biosensors were obtained through the deposition of enzymatic layers and the cross-linking process between enzymes and BSA in saturated glutaraldehyde vapour. The response of the various biosensors, described previously, were compared with the values of total organic carbon （TOC）, and those of organic nitrogen （No~）, as determined by the laboratory accredits （CEMAGREF of Lyon） using the traditional method of analysis （NF EN 1484, infrared spectroscopy） and （NF EN 25663, mineralization/colorimetry assay） respectively for each water sample obtained from different sites in Lyon （France）. The linear correlations obtained with the response of the seven biosensors showed the most important indices of correlations for the biosensor with two enzymatic layers： proteinase K ＋ pronase （pkp）. The optimum conditions for the preparation of the pkp biosensor increased the sensitivity and gave a limit of quantification of 0.583 μg/L for TOC and 0.218 μg/L for Norg in water samples. This sensor shows good reproducibility （2.28%）, a capacity to be used at temperatures range 10-- 30℃ （depending on the season） and moreover a long lifetime （5 weeks）.展开更多
Sensory data are, due to the lack of an absolute reference, imprecise and uncertain data. Fuzzy logic can handle uncertainty and can be used in approximate reasoning. Automatic learning procedures allow to generate fu...Sensory data are, due to the lack of an absolute reference, imprecise and uncertain data. Fuzzy logic can handle uncertainty and can be used in approximate reasoning. Automatic learning procedures allow to generate fuzzy reasoning rules from data including numerical and symbolic or sensory variables. We briefly present an induction method that was developed to extract qualitative knowledge from data samples. The induction process is run under interpretability constraints to ensure the fuzzy rules have a meaning for the human expert. We then study two applied problems in the food industry: sensory evaluation and process modeling.展开更多
During pesticide spraying, some of the smallest or slowest droplets do not reach the target and may contribute to spray drift. Therefore, it is important to characterize droplet size and velocity close to the nozzle e...During pesticide spraying, some of the smallest or slowest droplets do not reach the target and may contribute to spray drift. Therefore, it is important to characterize droplet size and velocity close to the nozzle exit. The aim of this study was to contribute to the comprehension of spray formation. Surfactant influence on spray characteristics was studied by comparing water spray with sprays containing three different surfactants, Two nozzles including a classical hollow cone nozzle ATR （Albuz, France） and an air-induced hollow cone nozzle TVI which is a low-drift nozzle （Albuz, France） were chosen. Radial profiles of the axial velocity component and Sauter mean diameter at two axial distances from the nozzle exit were measured using a Phase Doppler Particle Analyzer （PDPA）. Results showed that sprays issued from ATR and TVI nozzles were very different, even when water was sprayed. Effect of adding surfactant depended on the nozzle type. Sheet thickness was reduced by adding Elton and Heliosol regardless of the nozzle type. They reduced spray angle of ATR nozzle spray but did not affect that of YVI nozzle. Break-Thru has a slight effect when sprayed through the ATR nozzle, but it has the most pronounced effect on the SMD when sprayed through the TVI nozzle.展开更多
In periurban zones, urban wet weather discharges have been recognized as the most significant vector of pollution in aquatic environments. The discharge of this water without treatment into the aquatic environment cou...In periurban zones, urban wet weather discharges have been recognized as the most significant vector of pollution in aquatic environments. The discharge of this water without treatment into the aquatic environment could present an ecotoxicological risk for biocenosis. The aim of the INVASION project is to assess the potential ecotoxicological impact of a combined sewer overflow (CSO) on a peri-urban stream. A comparative study between upstream and downstream areas of the CSO allowed observing significant effects of this overflow on the river. We studied three layers of stream: surface water, benthic layer and hyporheic layer. To characterize the potential ecotoxicological risk of water and sediments, we used a battery of 4 bioassays: Daphnia magna, Vibrio fischeri, Brachionus calyciflorus and Heterocypris incongruens. In parallel, we measured the physico-chemical parameters: ammonium (NH4+), chromium (Cr), copper (Cu) and lead (Pb). An ecological risk is greatest for the hyporheic zone in downstream river, particularly for the solid phase. These results corroborated with the physico-chemical data obtained.展开更多
In the French Alps, some grasslands have been abandoned, others are invaded by scrub whereas they are still used by farmers What are the relationships between land use changes and other changes at farm level that lead...In the French Alps, some grasslands have been abandoned, others are invaded by scrub whereas they are still used by farmers What are the relationships between land use changes and other changes at farm level that lead to scrub invasion？ We hypothesize that they are linked by two work organization processes： process of changes （changes in the household and farm） leading to less intensive land use; and annual processes （sequences of activities during the year） and their repetition from one year to another, leading to insufficient land maintenance. In this paper, we present a study carried out in the Northern French Alps, based on surveys with livestock farmers. It appears that land use changes are often the consequence of other changes made to address work problems, and land use sequences are defined according to workforce and prioritization of tasks. This highlights the importance of considering farmers as workers in order to evaluate land use changes at the farm level and to link them to the human dimension within farming systems.展开更多
Dry drainage is thought to be a potential approach to control soil salinity. This study took the Hetao Irrigation District as an example and evaluated the effectiveness of dry drainage by using remote sensing, a conce...Dry drainage is thought to be a potential approach to control soil salinity. This study took the Hetao Irrigation District as an example and evaluated the effectiveness of dry drainage by using remote sensing, a conceptual model and a field experiment. Archived remote sensing images from 1973―2006 were used to delineate the temporal and spatial change of soil salinity. The conceptual water and salt balance model was used to evaluate the role of dry drainage in removing excess salt from the irrigated land. The field experiment was performed to get field validation and give more accurate estimation. The results show that dry drainage did contribute to remove excess salt from the irrigated land and succeed in controlling soil salinity in the Hetao Irrigation District. It can be taken as an alternative approach in (semi-)arid area where artificial drainage is not applicable.展开更多
We develop a two-relaxation-time (TRT) Lattice Boltzmann model for hydrodynamicequations with variable source terms based on equivalent equilibriumfunctions. A special parametrization of the free relaxation parameter ...We develop a two-relaxation-time (TRT) Lattice Boltzmann model for hydrodynamicequations with variable source terms based on equivalent equilibriumfunctions. A special parametrization of the free relaxation parameter is derived. Itcontrols, in addition to the non-dimensional hydrodynamic numbers, any TRT macroscopicsteady solution and governs the spatial discretization of transient flows. Inthis framework, the multi-reflection approach [16, 18] is generalized and extended forDirichlet velocity, pressure and mixed (pressure/tangential velocity) boundary conditions.We propose second and third-order accurate boundary schemes and adapt themfor corners. The boundary schemes are analyzed for exactness of the parametrization,uniqueness of their steady solutions, support of staggered invariants and for the effectiveaccuracy in case of time dependent boundary conditions and transient flow.When the boundary scheme obeys the parametrization properly, the derived permeabilityvalues become independent of the selected viscosity for any porous structureand can be computed efficiently. The linear interpolations [5, 46] are improved withrespect to this property.展开更多
Aims In eroded lands of the French Southern Alps,burial of early established seedlings under marly sediment weakens the effect of vegetation on soil stabilization and sediment trapping.Therefore,this protective role i...Aims In eroded lands of the French Southern Alps,burial of early established seedlings under marly sediment weakens the effect of vegetation on soil stabilization and sediment trapping.Therefore,this protective role is largely dependent on species’resistance to burial,and the understanding of species’tolerance to this environmental disturbance is highly valuable for basic knowledge on plant succession and for ecological restoration purposes.Methods The response of five woody species with contrasting ecological requirements and natural habitats—three tree species,Pinus nigra,Robinia pseudoacacia and Acer campestre,and two shrubs,Ononis fruticosa and Hippophae rhamnoides—to experimental burial under marly sediment was studied.Seedlings were exposed to three burial levels:no burial(control),partial burial(50%of seedling height)and complete burial(100%of seedling height).Burial tolerance was evaluated based on seedling survival,height and biomass.Biomass allocation to shoots and roots and soluble sugar and starch contents in roots and stems were measured to identify plant traits that determine species response to burial.Important Findings All species survived partial burial but only A.campestre seedlings emerged from complete burial.Tree species were more tolerant to burial and buried plants showed no significant differences with control.The two shrubs were found less tolerant and buried plants showed slower growth than controls.The results showed that species response was not related to initial soluble and starch content in roots and stems,but instead to biomass allocation pattern flexibility.展开更多
For simple hydrodynamic solutions, where the pressure and the velocity arepolynomial functions of the coordinates, exact microscopic solutions are constructedfor the two-relaxation-time (TRT) Lattice Boltzmann model w...For simple hydrodynamic solutions, where the pressure and the velocity arepolynomial functions of the coordinates, exact microscopic solutions are constructedfor the two-relaxation-time (TRT) Lattice Boltzmann model with variable forcing andsupported by exact boundary schemes. We show how simple numerical and analyticalsolutions can be interrelated for Dirichlet velocity, pressure and mixed (pressure/tangential velocity) multi-reflection (MR) type schemes. Special care is taken toadapt themfor corners, to examine the uniqueness of the obtained steady solutions andstaggered invariants, to validate their exact parametrization by the non-dimensionalhydrodynamic and a “kinetic” (collision) number. We also present an inlet/outlet“constant mass flux” condition. We show, both analytically and numerically, that thekinetic boundary schemes may result in the appearance of Knudsen layers which arebeyond the methodology of the Chapman-Enskog analysis. Time dependent Dirichletboundary conditions are investigated for pulsatile flow driven by an oscillating pressuredrop or forcing. Analytical approximations are constructed in order to extend thepulsatile solution for compressible regimes.展开更多
基金supported by the National Natural Science Foundation of China (No. 51078035, 20977008)the Fundamental Research Funds for the Central Universities (No. BLJC200902, TD2010-5)+1 种基金the High-Tech Research and Development Program (863) of China (No. 2007AA06Z301)the Major Projects on Control and Rectification of Water Body Pollution (No. 2008ZX07422-002-004, 2008ZX07314-006)
文摘The changes in the physical characteristics of unconditioned and conditioned anaerobic digested sludge （ADS） biosolids, such as capillary suction time （CST）, yield stress, average size and fractal dimensions, were investigated through a CST test, transient and dynamic rheological test and image analysis. The results showed that the optimum polymer dose range was observed when CST or its reciprocal value was employed as an indicator. There were good correlations between the yield stresses determined from both a controlled shear stress test and a strain amplitude sweep test. The yield stress and storage modulus （G＇） increased as the polymer dose increased in most cases. A frequency sweep test revealed that polymer conditioning could extend the frequency sweep ranges for their elastic behaviors over viscous behaviors as well as the gel-like structure in the linear viscoelastic range. These results implied that more deformation energy was stored in this rigid structure, and that elastic behavior became increasingly dominant with the addition of the polymer in most cases, In addition, both the average sizes and two-dimensional fractal dimensions for conditioned ADS biosolids presented a similar up-climax-down variation trend as the polymer doses increased, whereas the critical polymer doses at the highest average sizes or two-dimensional fractal dimensions, were different. Correlation analysis revealed that the conditioned ADS dewaterability was not correlated with the yield stresses, while the average sizes or the two-dimensional fractal dimensions for conditioned ADS biosolids could be taken as the indication parameters for ADS dewaterability.
文摘WUIma -which stands for Wildland-Urban Interface MAPping-is a software tool based on a GIS model （developped with Arcgis functions） designed to map wildland-urban interfaces at a large scale over a large area. The main outputs of WUImap are： （1） the map of twelve types of wildland-urban interfaces existing on the territory; （2） the map of four housing configuration （isolated, scattered, dense and very dense clustered housing） related to wildland-urban interfaces （WUI）. These maps are produced according to the method of WUI characterization combining housing configuration and horizontal structure of vegetation. Required inputs to map WUI are the layer of the residential house, the layer defining the fire sensitive area and the layer of the index of aggregation calculated on vegetation. The method of WUI characterization and mapping incorporated into WUImap has been evaluated and applied on real cases with good results. WUlmap has applicability as a decision support aid in a wide variety of land management ranging from fire management and fire prevention to analysis of WUI spread and land cover dynamic. The core method underlying the WUlrnap is summarized in the present paper.
文摘This article describes a conductometric bi-layer based bienzyme biosensor for the detection of proteins as a marker of organic matter in rivers. Proteins were chosen to be used as indicators of urban pollution. The working mechanism of the bienzyme biosensor is based on the enzymatic hydrolysis of proteins into several fractions （peptides and amino acids）, which results in a local conductivity change depending of the concentration of proteins. In this work, we began with the optimization of biosensor response using bovine serum albumin （BSA） as standard protein. For this objective seven enzymatic biosensors were prepared： four enzymatic sensors with only one layer of enzyme （proteinase K, trypsin, pronase or protease X） and three other enzymatic sensors with two layers （first layer： membrane containing proteinase K; second layer： one of the three other enzymes： trypsin, pronase or protease X）. The biosensors were obtained through the deposition of enzymatic layers and the cross-linking process between enzymes and BSA in saturated glutaraldehyde vapour. The response of the various biosensors, described previously, were compared with the values of total organic carbon （TOC）, and those of organic nitrogen （No~）, as determined by the laboratory accredits （CEMAGREF of Lyon） using the traditional method of analysis （NF EN 1484, infrared spectroscopy） and （NF EN 25663, mineralization/colorimetry assay） respectively for each water sample obtained from different sites in Lyon （France）. The linear correlations obtained with the response of the seven biosensors showed the most important indices of correlations for the biosensor with two enzymatic layers： proteinase K ＋ pronase （pkp）. The optimum conditions for the preparation of the pkp biosensor increased the sensitivity and gave a limit of quantification of 0.583 μg/L for TOC and 0.218 μg/L for Norg in water samples. This sensor shows good reproducibility （2.28%）, a capacity to be used at temperatures range 10-- 30℃ （depending on the season） and moreover a long lifetime （5 weeks）.
文摘Sensory data are, due to the lack of an absolute reference, imprecise and uncertain data. Fuzzy logic can handle uncertainty and can be used in approximate reasoning. Automatic learning procedures allow to generate fuzzy reasoning rules from data including numerical and symbolic or sensory variables. We briefly present an induction method that was developed to extract qualitative knowledge from data samples. The induction process is run under interpretability constraints to ensure the fuzzy rules have a meaning for the human expert. We then study two applied problems in the food industry: sensory evaluation and process modeling.
文摘During pesticide spraying, some of the smallest or slowest droplets do not reach the target and may contribute to spray drift. Therefore, it is important to characterize droplet size and velocity close to the nozzle exit. The aim of this study was to contribute to the comprehension of spray formation. Surfactant influence on spray characteristics was studied by comparing water spray with sprays containing three different surfactants, Two nozzles including a classical hollow cone nozzle ATR （Albuz, France） and an air-induced hollow cone nozzle TVI which is a low-drift nozzle （Albuz, France） were chosen. Radial profiles of the axial velocity component and Sauter mean diameter at two axial distances from the nozzle exit were measured using a Phase Doppler Particle Analyzer （PDPA）. Results showed that sprays issued from ATR and TVI nozzles were very different, even when water was sprayed. Effect of adding surfactant depended on the nozzle type. Sheet thickness was reduced by adding Elton and Heliosol regardless of the nozzle type. They reduced spray angle of ATR nozzle spray but did not affect that of YVI nozzle. Break-Thru has a slight effect when sprayed through the ATR nozzle, but it has the most pronounced effect on the SMD when sprayed through the TVI nozzle.
文摘In periurban zones, urban wet weather discharges have been recognized as the most significant vector of pollution in aquatic environments. The discharge of this water without treatment into the aquatic environment could present an ecotoxicological risk for biocenosis. The aim of the INVASION project is to assess the potential ecotoxicological impact of a combined sewer overflow (CSO) on a peri-urban stream. A comparative study between upstream and downstream areas of the CSO allowed observing significant effects of this overflow on the river. We studied three layers of stream: surface water, benthic layer and hyporheic layer. To characterize the potential ecotoxicological risk of water and sediments, we used a battery of 4 bioassays: Daphnia magna, Vibrio fischeri, Brachionus calyciflorus and Heterocypris incongruens. In parallel, we measured the physico-chemical parameters: ammonium (NH4+), chromium (Cr), copper (Cu) and lead (Pb). An ecological risk is greatest for the hyporheic zone in downstream river, particularly for the solid phase. These results corroborated with the physico-chemical data obtained.
文摘In the French Alps, some grasslands have been abandoned, others are invaded by scrub whereas they are still used by farmers What are the relationships between land use changes and other changes at farm level that lead to scrub invasion？ We hypothesize that they are linked by two work organization processes： process of changes （changes in the household and farm） leading to less intensive land use; and annual processes （sequences of activities during the year） and their repetition from one year to another, leading to insufficient land maintenance. In this paper, we present a study carried out in the Northern French Alps, based on surveys with livestock farmers. It appears that land use changes are often the consequence of other changes made to address work problems, and land use sequences are defined according to workforce and prioritization of tasks. This highlights the importance of considering farmers as workers in order to evaluate land use changes at the farm level and to link them to the human dimension within farming systems.
基金Supported by the National Natural Science Foundation of China (Grant No. 50809050)the National Basic Research Program of China ("973" Project) (Grant No.2006CB403406)the National Key Technology R&D Program (Grant No. 2006BAD11B06)
文摘Dry drainage is thought to be a potential approach to control soil salinity. This study took the Hetao Irrigation District as an example and evaluated the effectiveness of dry drainage by using remote sensing, a conceptual model and a field experiment. Archived remote sensing images from 1973―2006 were used to delineate the temporal and spatial change of soil salinity. The conceptual water and salt balance model was used to evaluate the role of dry drainage in removing excess salt from the irrigated land. The field experiment was performed to get field validation and give more accurate estimation. The results show that dry drainage did contribute to remove excess salt from the irrigated land and succeed in controlling soil salinity in the Hetao Irrigation District. It can be taken as an alternative approach in (semi-)arid area where artificial drainage is not applicable.
文摘We develop a two-relaxation-time (TRT) Lattice Boltzmann model for hydrodynamicequations with variable source terms based on equivalent equilibriumfunctions. A special parametrization of the free relaxation parameter is derived. Itcontrols, in addition to the non-dimensional hydrodynamic numbers, any TRT macroscopicsteady solution and governs the spatial discretization of transient flows. Inthis framework, the multi-reflection approach [16, 18] is generalized and extended forDirichlet velocity, pressure and mixed (pressure/tangential velocity) boundary conditions.We propose second and third-order accurate boundary schemes and adapt themfor corners. The boundary schemes are analyzed for exactness of the parametrization,uniqueness of their steady solutions, support of staggered invariants and for the effectiveaccuracy in case of time dependent boundary conditions and transient flow.When the boundary scheme obeys the parametrization properly, the derived permeabilityvalues become independent of the selected viscosity for any porous structureand can be computed efficiently. The linear interpolations [5, 46] are improved withrespect to this property.
基金This work resulted from the project‘Genie biologique sur la Durance’,funded by EDF(Electricitede France)Agence de l’eau Rhone Mediterranee et Corse,Region Provence Alpes Cote d’Azurthe European Union with FEDER funds.
文摘Aims In eroded lands of the French Southern Alps,burial of early established seedlings under marly sediment weakens the effect of vegetation on soil stabilization and sediment trapping.Therefore,this protective role is largely dependent on species’resistance to burial,and the understanding of species’tolerance to this environmental disturbance is highly valuable for basic knowledge on plant succession and for ecological restoration purposes.Methods The response of five woody species with contrasting ecological requirements and natural habitats—three tree species,Pinus nigra,Robinia pseudoacacia and Acer campestre,and two shrubs,Ononis fruticosa and Hippophae rhamnoides—to experimental burial under marly sediment was studied.Seedlings were exposed to three burial levels:no burial(control),partial burial(50%of seedling height)and complete burial(100%of seedling height).Burial tolerance was evaluated based on seedling survival,height and biomass.Biomass allocation to shoots and roots and soluble sugar and starch contents in roots and stems were measured to identify plant traits that determine species response to burial.Important Findings All species survived partial burial but only A.campestre seedlings emerged from complete burial.Tree species were more tolerant to burial and buried plants showed no significant differences with control.The two shrubs were found less tolerant and buried plants showed slower growth than controls.The results showed that species response was not related to initial soluble and starch content in roots and stems,but instead to biomass allocation pattern flexibility.
文摘For simple hydrodynamic solutions, where the pressure and the velocity arepolynomial functions of the coordinates, exact microscopic solutions are constructedfor the two-relaxation-time (TRT) Lattice Boltzmann model with variable forcing andsupported by exact boundary schemes. We show how simple numerical and analyticalsolutions can be interrelated for Dirichlet velocity, pressure and mixed (pressure/tangential velocity) multi-reflection (MR) type schemes. Special care is taken toadapt themfor corners, to examine the uniqueness of the obtained steady solutions andstaggered invariants, to validate their exact parametrization by the non-dimensionalhydrodynamic and a “kinetic” (collision) number. We also present an inlet/outlet“constant mass flux” condition. We show, both analytically and numerically, that thekinetic boundary schemes may result in the appearance of Knudsen layers which arebeyond the methodology of the Chapman-Enskog analysis. Time dependent Dirichletboundary conditions are investigated for pulsatile flow driven by an oscillating pressuredrop or forcing. Analytical approximations are constructed in order to extend thepulsatile solution for compressible regimes.
