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Michel Mench - One of the best experts on this subject based on the ideXlab platform.
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degradation pathways of holocellulose lignin and α cellulose from pteris vittata Fronds in sub and super critical conditions
Biomass & Bioenergy, 2012Co-Authors: Marion Carrier, Anne Loppinetserani, Christelle Absalon, Cyril Aymonier, Michel MenchAbstract:Abstract Fern (Pteris vittata L.) Fronds were collected in the Reppel small-scale field experiment aiming at arsenic phytoextraction. Three organic fractions, i.e. holocellulose, hemicelluloses, and lignin, were extracted from the Fronds. The frond biomass as well as the holocellulose, hemicelluloses, and lignin fractions were converted by sub- and super critical water treatments at low temperatures, 300 °C and 400 °C with 25 MPa, and organic products were identified. This study highlighted that hemicelluloses and lignin are reported as the major sources of cyclopentenones and furfurals, 5 carbons-containing products. The degradation of carbohydrates part (holocellulose and α-cellulose) provided the largest range of by-products due to the thermal resistance of the lignin. The control of biochemical families's content and temperature should determine the presence of required by-products. The fact that no ‘synthetic’ materials but original materials, i.e. holocellulose, α-cellulose and lignin directly extracted from control fern Fronds have been converted revealed the presence of benzenes and cyclopentenones, by-products which have not been reported by the literature.
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Degradation pathways of holocellulose, lignin and a-cellulose from Pteris vittata Fronds in sub- and super critical conditions
Biomass and Bioenergy, 2012Co-Authors: Marion Carrier, Christelle Absalon, Cyril Aymonier, Anne Loppinet-serani, Michel MenchAbstract:Fern (Pterisvittata L.) Fronds were collected in the Reppel small-scale field experiment aiming at arsenic phytoextraction. Three organic fractions, i.e. holocellulose, hemicelluloses, and lignin, were extracted from the Fronds. The frond biomass as well as the holocellulose, hemicelluloses, and lignin fractions were converted by sub- and supercritical water treatments at low temperatures, 300 °C and 400 °C with 25 MPa, and organic products were identified. This study highlighted that hemicelluloses and lignin are reported as the major sources of cyclopentenones and furfurals, 5 carbons-containing products. The degradation of carbohydrates part (holocellulose and α-cellulose) provided the largest range of by-products due to the thermal resistance of the lignin. The control of biochemical families's content and temperature should determine the presence of required by-products. The fact that no 'synthetic' materials but original materials, i.e. holocellulose, α-cellulose and lignin directly extracted from control fern Fronds have been converted revealed the presence of benzenes and cyclopentenones, by-products which have not been reported by the literature.
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conversion of fern pteris vittata l biomass from a phytoremediation trial in sub and supercritical water conditions
Biomass & Bioenergy, 2011Co-Authors: Marion Carrier, Anne Loppinetserani, Christelle Absalon, Cyril Aymonier, Frederic Marias, Michel MenchAbstract:Abstract Uncontaminated and As-contaminated Fronds of Pteris vittata L., an As-hyperaccumulator fern used to phytoextract As from contaminated soils and water, were converted by sub-critical water (300 °C, 25 Pa) and supercritical water (400 °C, 25 Pa) treatments. Frond biomass was reduced between 70 and 77%. Compared to sub-critical conditions, supercritical conditions decreased C and inorganic contents in both the solid and liquid phases for uncontaminated and contaminated Fronds and promoted CH 4 formation. Higher As, Fe and Zn contents in contaminated Fronds promoted decreasing C contents and the formations of cyclopentenones and benzenediols in the liquid phase. Al, Fe, P, Zn and Ca mainly remained in the solid phase whereas As and S were transferred to the liquid phase for both phytomasses. As the temperature increased from 300 °C to 400 °C, the concentrations of cyclopentenones and phenols in the liquid phase rose while those of guaiacols and other compounds decreased for both phytomasses. Arsenic in the liquid phase was removed by sorption on hydrous iron oxide.
Marion Carrier - One of the best experts on this subject based on the ideXlab platform.
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degradation pathways of holocellulose lignin and α cellulose from pteris vittata Fronds in sub and super critical conditions
Biomass & Bioenergy, 2012Co-Authors: Marion Carrier, Anne Loppinetserani, Christelle Absalon, Cyril Aymonier, Michel MenchAbstract:Abstract Fern (Pteris vittata L.) Fronds were collected in the Reppel small-scale field experiment aiming at arsenic phytoextraction. Three organic fractions, i.e. holocellulose, hemicelluloses, and lignin, were extracted from the Fronds. The frond biomass as well as the holocellulose, hemicelluloses, and lignin fractions were converted by sub- and super critical water treatments at low temperatures, 300 °C and 400 °C with 25 MPa, and organic products were identified. This study highlighted that hemicelluloses and lignin are reported as the major sources of cyclopentenones and furfurals, 5 carbons-containing products. The degradation of carbohydrates part (holocellulose and α-cellulose) provided the largest range of by-products due to the thermal resistance of the lignin. The control of biochemical families's content and temperature should determine the presence of required by-products. The fact that no ‘synthetic’ materials but original materials, i.e. holocellulose, α-cellulose and lignin directly extracted from control fern Fronds have been converted revealed the presence of benzenes and cyclopentenones, by-products which have not been reported by the literature.
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Degradation pathways of holocellulose, lignin and a-cellulose from Pteris vittata Fronds in sub- and super critical conditions
Biomass and Bioenergy, 2012Co-Authors: Marion Carrier, Christelle Absalon, Cyril Aymonier, Anne Loppinet-serani, Michel MenchAbstract:Fern (Pterisvittata L.) Fronds were collected in the Reppel small-scale field experiment aiming at arsenic phytoextraction. Three organic fractions, i.e. holocellulose, hemicelluloses, and lignin, were extracted from the Fronds. The frond biomass as well as the holocellulose, hemicelluloses, and lignin fractions were converted by sub- and supercritical water treatments at low temperatures, 300 °C and 400 °C with 25 MPa, and organic products were identified. This study highlighted that hemicelluloses and lignin are reported as the major sources of cyclopentenones and furfurals, 5 carbons-containing products. The degradation of carbohydrates part (holocellulose and α-cellulose) provided the largest range of by-products due to the thermal resistance of the lignin. The control of biochemical families's content and temperature should determine the presence of required by-products. The fact that no 'synthetic' materials but original materials, i.e. holocellulose, α-cellulose and lignin directly extracted from control fern Fronds have been converted revealed the presence of benzenes and cyclopentenones, by-products which have not been reported by the literature.
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conversion of fern pteris vittata l biomass from a phytoremediation trial in sub and supercritical water conditions
Biomass & Bioenergy, 2011Co-Authors: Marion Carrier, Anne Loppinetserani, Christelle Absalon, Cyril Aymonier, Frederic Marias, Michel MenchAbstract:Abstract Uncontaminated and As-contaminated Fronds of Pteris vittata L., an As-hyperaccumulator fern used to phytoextract As from contaminated soils and water, were converted by sub-critical water (300 °C, 25 Pa) and supercritical water (400 °C, 25 Pa) treatments. Frond biomass was reduced between 70 and 77%. Compared to sub-critical conditions, supercritical conditions decreased C and inorganic contents in both the solid and liquid phases for uncontaminated and contaminated Fronds and promoted CH 4 formation. Higher As, Fe and Zn contents in contaminated Fronds promoted decreasing C contents and the formations of cyclopentenones and benzenediols in the liquid phase. Al, Fe, P, Zn and Ca mainly remained in the solid phase whereas As and S were transferred to the liquid phase for both phytomasses. As the temperature increased from 300 °C to 400 °C, the concentrations of cyclopentenones and phenols in the liquid phase rose while those of guaiacols and other compounds decreased for both phytomasses. Arsenic in the liquid phase was removed by sorption on hydrous iron oxide.
Hannah L Stewa - One of the best experts on this subject based on the ideXlab platform.
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morphological variation and phenotypic plasticity of buoyancy in the macroalga turbinaria ornata across a barrier reef
Marine Biology, 2006Co-Authors: Hannah L StewaAbstract:Many aspects of morphology of benthic algae (length, surface area-to-volume ratio, and blade undulation) are plastic traits that vary in response to physical factors (such as light or water flow environment). This study examines whether frond buoyancy is a plastic trait, and whether differences in morphology including buoyancy affect the potential persistence of macroalgae in habitats characterized by different water flow regimes. Fronds of the tropical alga Turbinaria ornata in protected backreef environments in Moorea, French Polynesia possess pneumatocysts (gas-filled floats) and experience positive buoyant forces, whereas Fronds in wave-exposed forereef sites either lack pneumatocysts entirely or have very small, rudimentary pneumatocysts and experience negative buoyant forces. Forereef Fronds transplanted to the backreef developed pneumatocysts and experienced increased buoyant force indicating that buoyancy is a phenotypically plastic trait in T. ornata. In comparing the potential for dislodgement by drag, drag was greater on forereef Fronds at low flow speeds as these Fronds were stiffer and did not bend over at low flow speeds and therefore were less streamlined in the flow than backreef algae, which bent easily. The environmental stress factor (ESF) (a measure of the likelihood of detachment for a frond in its habitat) was higher for forereef than backreef Fronds at all flow speeds. When examined with respect to the flow velocities likely in their respective habitats however, the chance of detachment for backreef and forereef was similar. Neither backreef nor forereef Fronds were predicted to break under normal, non-storm conditions, but both were predicted to break in storms. Strong forereef morphologies are well suited to habitats characterized by rapid flow, whereas the weaker, buoyant, tall backreef Fronds are well suited to habitats where crowding and shading is common but hydrodynamic forces are low.
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ontogenetic changes in buoyancy breaking strength extensibility and reproductive investment in a drifting macroalga turbinaria ornata phaeophyta 1
Journal of Phycology, 2006Co-Authors: Hannah L StewaAbstract:Turbinaria ornata (Turner) J. Agardh is a tropical alga that disperses by detached, reproductively mature floating Fronds. Material properties (breaking stress, breaking extension), buoyancy, and the proportion of reproductive tissue per frond were measured for juvenile, adult, and old Fronds of T. ornata. Correlations between these factors indicate that as Fronds age and become more reproductively mature, the tissue in their stipes (where they break) becomes weaker, more brittle, and the overall buoyancy of the frond increases. Measurement of drag force experienced by Fronds from each ontogenetic stage allowed calculation of the environmental stress factor (ESF), which indicates the likelihood of detachment of a frond in the flow environment of its habitat. The ESF for Fronds of each ontogenetic stage predicted that reproductively mature Fronds (adult and old) break more readily than immature (juvenile) Fronds. Increased proportions of reproductively mature Fronds in floating rafts following storms compared with the proportion of mature Fronds attached to the substratum support the ESF predictions. This combination of ontogenetic changes in material properties, buoyancy, and reproductive maturity in combination with the life history of T. ornata may contribute to the dispersal of this alga throughout French Polynesia.
Lena Q - One of the best experts on this subject based on the ideXlab platform.
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comparison of arsenic accumulation in 18 fern species and four pteris vittata accessions
Bioresource Technology, 2010Co-Authors: Mrittunjai Srivastava, Jorge Antonio Gonzaga Santos, Pratibha Srivastava, Lena QAbstract:Abstract This study evaluated the ability and mechanisms of 19 Pteris and non- Pteris species to accumulate arsenic (As) in a hydroponic system spiked with 300 μM As. The study included four Pteris vittata accessions (China, India, Poland, and the United Kingdom), P . biaurita and 17 non- Pteris species. Among the accessions, P . vittata from China and UK were the most and the least efficient in terms of As accumulation. The non- Pteris species Chielanthes sinuta , Adiantum raddianum , Polystichum acrostichoides , Actiniopteris radiata , Pellaea rotundifolia , and Nephrolepis cordifolia concentrated As as effectively as the least efficient P. vittata ascension. As (III) in the Fronds of P . vittata accessions ranged from 59% to 89% and for non- Pteris species it ranged from 47% to 65%. Maximum As accumulation coincided with highest percentage of As (III) in the Fronds. The phosphorus (P) uptake of P. vittata accessions was 12–15 and 6–12 times greater than the As-uptake in the roots and Fronds, respectively. In contrast, the P-uptake of non- Pteris species ranged from 9 to 151 and from 4 to 162 times the As-uptake, in the roots and Fronds, respectively. Arsenic accumulation occurs at the expense of root and frond P-uptake. Root P-reduction is lower than frond and the P:As in the plant acquisition part (roots) is 1–3 times greater than that in accumulation part (Fronds). A . radiata , C . sinuta , and P. acrostichoides were identified as potential As accumulators.
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phytoremediation of an arsenic contaminated site using pteris vittata l a two year study
International Journal of Phytoremediation, 2006Co-Authors: G M Kertulistartar, Lena Q, C Tu, T ChirenjeAbstract:A field study was conducted to determine the efficiency of Chinese brake fern (Pteris vittata L.), an arsenic hyperaccumulator, on removal of arsenic from soil at an arsenic- contaminated site. Chinese brake ferns were planted on a site previously used to treat wood with chromated copper arsenate (CCA). Arsenic concentrations in surface and profile soil samples were determined for 2000, 2001, and 2002. In both 2001 and 2002, senesced and senescing Fronds only, as well as all Fronds, were harvested. Frond arsenic concentrations were not significantly different between the three harvests. Compared to senesced Fronds, live Fronds resulted in the greatest amount of arsenic removal. There were no significant differences in soil arsenic concentrations between 2000, 2001, and 2002, primarily due to the extreme variability in soil arsenic concentrations. However, the mean surface soil arsenic was reduced from 190 to 140 mg kg−1. Approximately 19.3 g of arsenic were removed from the soil by Chinese brake fern. The...
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effects of arsenic on concentration and distribution of nutrients in the Fronds of the arsenic hyperaccumulator pteris vittata l
Environmental Pollution, 2005Co-Authors: C Tu, Lena QAbstract:Abstract Pteris vittata was the first terrestrial plant known to hyperaccumulate arsenic (As). However, it is unclear how As hyperaccumulation influences nutrient uptake by this plant. P. vittata fern was grown in soil spiked with 0–500 mg As kg −1 in the greenhouse for 24 weeks. The concentrations of essential macro- (P, K, Ca, and Mg) and micro- (Fe, Mn, Cu, Zn, B and Mo) elements in the Fronds of different age were examined. Both macro- and micronutrients in the Fronds were found to be within the normal concentration ranges for non-hyperaccumulators. However, As hyperaccumulation did influence the elemental distribution among Fronds of different age of P. vittata . Arsenic-induced P and K enhancements in the Fronds contributed to the As-induced growth stimulation at low As levels. The frond P/As molar ratios of 1.0 can be used as the threshold value for normal growth of P. vittata . Potassium may function as a counter-cation for As in the Fronds as shown by the As-induced K increases in the Fronds. The present findings not only demonstrate that P. vittata has the ability to maintain adequate concentrations of essential nutrients while hyperaccumulating As from the soil, but also have implications for soil management (fertilization in particular) of P. vittata in As phytoextraction practice.
Christelle Absalon - One of the best experts on this subject based on the ideXlab platform.
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degradation pathways of holocellulose lignin and α cellulose from pteris vittata Fronds in sub and super critical conditions
Biomass & Bioenergy, 2012Co-Authors: Marion Carrier, Anne Loppinetserani, Christelle Absalon, Cyril Aymonier, Michel MenchAbstract:Abstract Fern (Pteris vittata L.) Fronds were collected in the Reppel small-scale field experiment aiming at arsenic phytoextraction. Three organic fractions, i.e. holocellulose, hemicelluloses, and lignin, were extracted from the Fronds. The frond biomass as well as the holocellulose, hemicelluloses, and lignin fractions were converted by sub- and super critical water treatments at low temperatures, 300 °C and 400 °C with 25 MPa, and organic products were identified. This study highlighted that hemicelluloses and lignin are reported as the major sources of cyclopentenones and furfurals, 5 carbons-containing products. The degradation of carbohydrates part (holocellulose and α-cellulose) provided the largest range of by-products due to the thermal resistance of the lignin. The control of biochemical families's content and temperature should determine the presence of required by-products. The fact that no ‘synthetic’ materials but original materials, i.e. holocellulose, α-cellulose and lignin directly extracted from control fern Fronds have been converted revealed the presence of benzenes and cyclopentenones, by-products which have not been reported by the literature.
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Degradation pathways of holocellulose, lignin and a-cellulose from Pteris vittata Fronds in sub- and super critical conditions
Biomass and Bioenergy, 2012Co-Authors: Marion Carrier, Christelle Absalon, Cyril Aymonier, Anne Loppinet-serani, Michel MenchAbstract:Fern (Pterisvittata L.) Fronds were collected in the Reppel small-scale field experiment aiming at arsenic phytoextraction. Three organic fractions, i.e. holocellulose, hemicelluloses, and lignin, were extracted from the Fronds. The frond biomass as well as the holocellulose, hemicelluloses, and lignin fractions were converted by sub- and supercritical water treatments at low temperatures, 300 °C and 400 °C with 25 MPa, and organic products were identified. This study highlighted that hemicelluloses and lignin are reported as the major sources of cyclopentenones and furfurals, 5 carbons-containing products. The degradation of carbohydrates part (holocellulose and α-cellulose) provided the largest range of by-products due to the thermal resistance of the lignin. The control of biochemical families's content and temperature should determine the presence of required by-products. The fact that no 'synthetic' materials but original materials, i.e. holocellulose, α-cellulose and lignin directly extracted from control fern Fronds have been converted revealed the presence of benzenes and cyclopentenones, by-products which have not been reported by the literature.
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conversion of fern pteris vittata l biomass from a phytoremediation trial in sub and supercritical water conditions
Biomass & Bioenergy, 2011Co-Authors: Marion Carrier, Anne Loppinetserani, Christelle Absalon, Cyril Aymonier, Frederic Marias, Michel MenchAbstract:Abstract Uncontaminated and As-contaminated Fronds of Pteris vittata L., an As-hyperaccumulator fern used to phytoextract As from contaminated soils and water, were converted by sub-critical water (300 °C, 25 Pa) and supercritical water (400 °C, 25 Pa) treatments. Frond biomass was reduced between 70 and 77%. Compared to sub-critical conditions, supercritical conditions decreased C and inorganic contents in both the solid and liquid phases for uncontaminated and contaminated Fronds and promoted CH 4 formation. Higher As, Fe and Zn contents in contaminated Fronds promoted decreasing C contents and the formations of cyclopentenones and benzenediols in the liquid phase. Al, Fe, P, Zn and Ca mainly remained in the solid phase whereas As and S were transferred to the liquid phase for both phytomasses. As the temperature increased from 300 °C to 400 °C, the concentrations of cyclopentenones and phenols in the liquid phase rose while those of guaiacols and other compounds decreased for both phytomasses. Arsenic in the liquid phase was removed by sorption on hydrous iron oxide.
