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Krzysztof Strzelec - One of the best experts on this subject based on the ideXlab platform.
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thermoplastic elastomer biocomposites filled with cereal straw fibers obtained with different processing methods preparation and properties
Polymers, 2019Co-Authors: Justyna Miedzianowska, Marcin Maslowski, Krzysztof StrzelecAbstract:This work is focused on thermoplastic elastomers composites (TPEs) reinforced with straw. Crop Waste with different particle size was used as a filler of ethylene-octene rubber (EOR). Application of cheap and renewable natural fiber like straw into a TPE medium is not fully recognized and explored. The effect of fiber orientation induced by two processing techniques on the different mechanical properties of composites was investigated. Microscopic images were used to present the tested straw fractions and observe the arrangement and dispersion of fibers in the polymer matrix. It was found that the usage of an injection molding process allowed for the forming of a more homogenous dispersion of short fiber particles in the elastomer matrix. An oriented straw filler and polymer chains resulted in the improved mechanical strength of the whole system as evidenced by the obtained values of tensile strength almost two times higher for injected composites. In addition, all composites showed very good resistance to thermo-oxidative aging, where the aging factor oscillated within the limits of one, regardless of the processing method and the amount of bioadditive used. On the other hand, vulcanized composites were characterized by greater tear resistance, for which Fmit values increased by up to 600% compared to the reference sample.
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Thermoplastic Elastomer Biocomposites Filled with Cereal Straw Fibers Obtained with Different Processing Methods—Preparation and Properties
MDPI AG, 2019Co-Authors: Justyna Miedzianowska, Marcin Masłowski, Krzysztof StrzelecAbstract:This work is focused on thermoplastic elastomers composites (TPEs) reinforced with straw. Crop Waste with different particle size was used as a filler of ethylene-octene rubber (EOR). Application of cheap and renewable natural fiber like straw into a TPE medium is not fully recognized and explored. The effect of fiber orientation induced by two processing techniques on the different mechanical properties of composites was investigated. Microscopic images were used to present the tested straw fractions and observe the arrangement and dispersion of fibers in the polymer matrix. It was found that the usage of an injection molding process allowed for the forming of a more homogenous dispersion of short fiber particles in the elastomer matrix. An oriented straw filler and polymer chains resulted in the improved mechanical strength of the whole system as evidenced by the obtained values of tensile strength almost two times higher for injected composites. In addition, all composites showed very good resistance to thermo-oxidative aging, where the aging factor oscillated within the limits of one, regardless of the processing method and the amount of bioadditive used. On the other hand, vulcanized composites were characterized by greater tear resistance, for which Fmit values increased by up to 600% compared to the reference sample
Geert-jan Witkamp - One of the best experts on this subject based on the ideXlab platform.
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Environmentally benign supercritical CO2 extraction of galanthamine from floricultural Crop Waste of Narcissus pseudonarcissus
Journal of Supercritical Fluids, 2014Co-Authors: Orchidea Rachmaniah, Robert Verpoorte, Young Hae Choi, Inaki Arruabarrena, Bas Vermeulen, Jaap Van Spronsen, Geert-jan WitkampAbstract:The influence of diverse factors on the supercritical fluid extraction (SFE) with supercritical CO2 (scCO2) of galanthamine from bulbs of Narcissus pseudonarcissus cv. Carlton was investigated. The parameters that were studied were CO2 density (temperature and pressure), flow rate and plant material particle size and pre-treatment. The highest yield (303 μg/g) was achieved by extracting 53–1000 μm particle-size powdered dried bulb material moistened with NH4OH (25%, v/v) at 70 °C, 220 bar (690 kg/m3) for 3 h. Other N. pseudonarcissus alkaloids such as O-methyllycorenine and haemanthamine were also obtained. N. pseudonarcissus alkaloids as free bases are highly soluble in CO2 at a high pH as opposed to the slightly soluble salt form in which they are generally found in plants. Therefore, plant material pre-treatment with a base is an essential step for galanthamine extraction. Scanning electron microscope (SEM) results also revealed that the desorption of N. pseudonarcissus alkaloids from the plant material rather than the solubility of the alkaloids in the scCO2 plays a major role in this scCO2 extraction. This extraction method has a good potential for industrial application.
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Environmentally benign supercritical CO2 extraction of galanthamine from floricultural Crop Waste of Narcissus pseudonarcissus
The Journal of Supercritical Fluids, 2014Co-Authors: Orchidea Rachmaniah, Robert Verpoorte, Young Hae Choi, Inaki Arruabarrena, Bas Vermeulen, Jaap Van Spronsen, Geert-jan WitkampAbstract:The influence of diverse factors on the supercritical fluid extraction (SFE) with supercritical CO2 (scCO2) of galanthamine from bulbs of Narcissus pseudonarcissus cv. Carlton was investigated. The parameters that were studied were CO2 density (temperature and pressure), flow rate and plant material particle size and pre-treatment. The highest yield (303 μg/g) was achieved by extracting 53–1000 μm particle-size powdered dried bulb material moistened with NH4OH (25%, v/v) at 70 °C, 220 bar (690 kg/m3) for 3 h. Other N. pseudonarcissus alkaloids such as O-methyllycorenine and haemanthamine were also obtained. N. pseudonarcissus alkaloids as free bases are highly soluble in CO2 at a high pH as opposed to the slightly soluble salt form in which they are generally found in plants. Therefore, plant material pre-treatment with a base is an essential step for galanthamine extraction. Scanning electron microscope (SEM) results also revealed that the desorption of N. pseudonarcissus alkaloids from the plant material rather than the solubility of the alkaloids in the scCO2 plays a major role in this scCO2 extraction. This extraction method has a good potential for industrial application.
Chandra Venkataraman - One of the best experts on this subject based on the ideXlab platform.
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Emissions from open biomass burning in India: Integrating the inventory approach with high-resolution Moderate Resolution Imaging Spectroradiometer (MODIS) active-fire and land cover data
Global Biogeochemical Cycles, 2006Co-Authors: Chandra Venkataraman, Gazala Habib, D. Kadamba, Manish Shrivastava, Jean-françois Léon, B. Crouzille, Olivier Boucher, David G. StreetsAbstract:[1] Climatological mean estimates of forest burning and Crop Waste burning based on broad assumptions of the amounts burned have so far been used for India in global inventories. Here we estimate open biomass burning representative of 1995–2000 from forests using burned area and biomass density specific for Indian ecosystems and Crop Waste burning as a balance between generation and known uses as fuel and fodder. High-resolution satellite data of active fires and land cover classification from MODIS, both on a scale of 1 km × 1 km, were used to capture the seasonal variability of forest and Crop Waste burning and in conjunction with field reporting. Correspondence in satellite-detected fire cycles with harvest season was used to identify types Crop Waste burned in different regions. The fire season in forest areas was from February to May, and that in Croplands varied with geographical location, with peaks in April and October, corresponding to the two major harvest seasons. Spatial variability in amount of forest biomass burned differed from corresponding forest fire counts with biomass burned being largest in central India but fire frequency being highest in the east-northeast. Unutilized Crop Waste and MODIS Cropland fires were predominant in the western Indo-Gangetic plain. However, the amounts of unutilized Crop Waste in the four regions were not strictly proportional to the fire counts. Fraction Crop Waste burned in fields ranged from 18 to 30% on an all-India basis and had a strong regional variation. Open burning contributes importantly (about 25%) to black carbon, organic matter, and carbon monoxide emissions, a smaller amount (9–13%) to PM2.5 (particulate mass in particles smaller than 2.5 micron diameter) and CO2 emissions, and negligibly to SO2 emissions (1%). However, it cannot explain a large “missing source” of BC or CO from India.
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new methodology for estimating biofuel consumption for cooking atmospheric emissions of black carbon and sulfur dioxide from india
Global Biogeochemical Cycles, 2004Co-Authors: Gazala Habib, Chandra Venkataraman, Manish Shrivastava, Rangan Banerjee, Jeffrey W Stehr, Russell R DickersonAbstract:[1] The dominance of biofuel combustion emissions in the Indian region, and the inherently large uncertainty in biofuel use estimates based on cooking energy surveys, prompted the current work, which develops a new methodology for estimating biofuel consumption for cooking. This is based on food consumption statistics, and the specific energy for food cooking. Estimated biofuel consumption in India was 379 (247– 584) Tg yr � 1 . New information on the user population of different biofuels was compiled at a state level, to derive the biofuel mix, which varied regionally and was 74:16:10%, respectively, of fuelwood, dung cake and Crop Waste, at a national level. Importantly, the uncertainty in biofuel use from quantitative error assessment using the new methodology is around 50%, giving a narrower bound than in previous works. From this new activity data and currently used black carbon emission factors, the black carbon (BC) emissions from biofuel combustion were estimated as 220 (65–760) Gg yr � 1 . The largest BC emissions were from fuelwood (75%), with lower contributions from dung cake (16%) and Crop Waste (9%). The uncertainty of 245% in the BC emissions estimate is now governed by the large spread in BC emission factors from biofuel combustion (122%), implying the need for reducing this uncertainty through measurements. Emission factors of SO2 from combustion of biofuels widely used in India were measured, and ranged 0.03–0.08 g kg � 1 from combustion of two wood species, 0.05–0.20 g kg � 1 from 10 Crop Waste types, and 0.88 g kg � 1 from dung cake, significantly lower than currently used emission factors for wood and Crop Waste. Estimated SO2 emissions from biofuels of 75 (36–160) Gg yr � 1 were about a factor of 3 lower than that in recent studies, with a large contribution from dung cake (73%), followed by fuelwood (21%) and Crop Waste (6%). INDEX TERMS: 0305 Atmospheric Composition and Structure: Aerosols and particles (0345, 4801); 0322 Atmospheric Composition and Structure: Constituent sources and sinks; 0345 Atmospheric Composition and Structure: Pollution—urban and regional (0305); 0365 Atmospheric Composition and Structure: Troposphere—composition and chemistry; KEYWORDS: aerosols, emission inventory, regional pollution
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inventory of aerosol and sulphur dioxide emissions from india part ii biomass combustion
Atmospheric Environment, 2002Co-Authors: Shekar M Reddy, Chandra VenkataramanAbstract:A spatially resolved biomass burning data set, and related emissions of sulphur dioxide and aerosol chemical constituents was constructed for India, for 1996–1997 and extrapolated to the INDOEX period (1998–1999). Sources include biofuels (wood, Crop Waste and dung-cake) and forest fires (accidental, shifting cultivation and controlled burning). Particulate matter (PM) emission factors were compiled from studies of Indian cooking stoves and from literature for open burning. Black carbon (BC) and organic matter (OM) emissions were estimated from these, accounting for combustion temperatures in cooking stoves. Sulphur dioxide emission factors were based on fuel sulphur content and reported literature measurements. Biofuels accounted 93% of total biomass consumption (577 MT yr 1 ), with forest fires contributing only 7%. The national average biofuel mixwas 56 : 21 : 23% of fuelwood, Crop Waste and dung-cake, respectively. Compared to fossil fuels, biomass combustion was a minor source of SO2 (7% of total), with higher emissions from dung-cake because of its higher sulphur content. PM2.5 emissions of 2.04 Tg yr 1 with an ‘‘inorganic fraction’’ of 0.86 Tg yr 1 were estimated. Biomass combustion was the major source of carbonaceous aerosols, accounting 0.25 Tg yr 1 of BC (72% of total) and 0.94 Tg yr 1 of OM (76% of total). Among biomass, fuelwood and Crop Waste were primary contributors to BC emissions, while dung-cake and forest fires were primary contributors to OM emissions. Northern and the east-coast India had high densities of biomass consumption and related emissions. Measurements of emission factors of SO2, size resolved aerosols and their chemical constituents for Indian cooking stoves are needed to refine the present estimates. r 2002 Elsevier Science Ltd. All rights reserved.
Justyna Miedzianowska - One of the best experts on this subject based on the ideXlab platform.
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thermoplastic elastomer biocomposites filled with cereal straw fibers obtained with different processing methods preparation and properties
Polymers, 2019Co-Authors: Justyna Miedzianowska, Marcin Maslowski, Krzysztof StrzelecAbstract:This work is focused on thermoplastic elastomers composites (TPEs) reinforced with straw. Crop Waste with different particle size was used as a filler of ethylene-octene rubber (EOR). Application of cheap and renewable natural fiber like straw into a TPE medium is not fully recognized and explored. The effect of fiber orientation induced by two processing techniques on the different mechanical properties of composites was investigated. Microscopic images were used to present the tested straw fractions and observe the arrangement and dispersion of fibers in the polymer matrix. It was found that the usage of an injection molding process allowed for the forming of a more homogenous dispersion of short fiber particles in the elastomer matrix. An oriented straw filler and polymer chains resulted in the improved mechanical strength of the whole system as evidenced by the obtained values of tensile strength almost two times higher for injected composites. In addition, all composites showed very good resistance to thermo-oxidative aging, where the aging factor oscillated within the limits of one, regardless of the processing method and the amount of bioadditive used. On the other hand, vulcanized composites were characterized by greater tear resistance, for which Fmit values increased by up to 600% compared to the reference sample.
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Thermoplastic Elastomer Biocomposites Filled with Cereal Straw Fibers Obtained with Different Processing Methods—Preparation and Properties
MDPI AG, 2019Co-Authors: Justyna Miedzianowska, Marcin Masłowski, Krzysztof StrzelecAbstract:This work is focused on thermoplastic elastomers composites (TPEs) reinforced with straw. Crop Waste with different particle size was used as a filler of ethylene-octene rubber (EOR). Application of cheap and renewable natural fiber like straw into a TPE medium is not fully recognized and explored. The effect of fiber orientation induced by two processing techniques on the different mechanical properties of composites was investigated. Microscopic images were used to present the tested straw fractions and observe the arrangement and dispersion of fibers in the polymer matrix. It was found that the usage of an injection molding process allowed for the forming of a more homogenous dispersion of short fiber particles in the elastomer matrix. An oriented straw filler and polymer chains resulted in the improved mechanical strength of the whole system as evidenced by the obtained values of tensile strength almost two times higher for injected composites. In addition, all composites showed very good resistance to thermo-oxidative aging, where the aging factor oscillated within the limits of one, regardless of the processing method and the amount of bioadditive used. On the other hand, vulcanized composites were characterized by greater tear resistance, for which Fmit values increased by up to 600% compared to the reference sample
Orchidea Rachmaniah - One of the best experts on this subject based on the ideXlab platform.
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Environmentally benign supercritical CO2 extraction of galanthamine from floricultural Crop Waste of Narcissus pseudonarcissus
Journal of Supercritical Fluids, 2014Co-Authors: Orchidea Rachmaniah, Robert Verpoorte, Young Hae Choi, Inaki Arruabarrena, Bas Vermeulen, Jaap Van Spronsen, Geert-jan WitkampAbstract:The influence of diverse factors on the supercritical fluid extraction (SFE) with supercritical CO2 (scCO2) of galanthamine from bulbs of Narcissus pseudonarcissus cv. Carlton was investigated. The parameters that were studied were CO2 density (temperature and pressure), flow rate and plant material particle size and pre-treatment. The highest yield (303 μg/g) was achieved by extracting 53–1000 μm particle-size powdered dried bulb material moistened with NH4OH (25%, v/v) at 70 °C, 220 bar (690 kg/m3) for 3 h. Other N. pseudonarcissus alkaloids such as O-methyllycorenine and haemanthamine were also obtained. N. pseudonarcissus alkaloids as free bases are highly soluble in CO2 at a high pH as opposed to the slightly soluble salt form in which they are generally found in plants. Therefore, plant material pre-treatment with a base is an essential step for galanthamine extraction. Scanning electron microscope (SEM) results also revealed that the desorption of N. pseudonarcissus alkaloids from the plant material rather than the solubility of the alkaloids in the scCO2 plays a major role in this scCO2 extraction. This extraction method has a good potential for industrial application.
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Environmentally benign supercritical CO2 extraction of galanthamine from floricultural Crop Waste of Narcissus pseudonarcissus
The Journal of Supercritical Fluids, 2014Co-Authors: Orchidea Rachmaniah, Robert Verpoorte, Young Hae Choi, Inaki Arruabarrena, Bas Vermeulen, Jaap Van Spronsen, Geert-jan WitkampAbstract:The influence of diverse factors on the supercritical fluid extraction (SFE) with supercritical CO2 (scCO2) of galanthamine from bulbs of Narcissus pseudonarcissus cv. Carlton was investigated. The parameters that were studied were CO2 density (temperature and pressure), flow rate and plant material particle size and pre-treatment. The highest yield (303 μg/g) was achieved by extracting 53–1000 μm particle-size powdered dried bulb material moistened with NH4OH (25%, v/v) at 70 °C, 220 bar (690 kg/m3) for 3 h. Other N. pseudonarcissus alkaloids such as O-methyllycorenine and haemanthamine were also obtained. N. pseudonarcissus alkaloids as free bases are highly soluble in CO2 at a high pH as opposed to the slightly soluble salt form in which they are generally found in plants. Therefore, plant material pre-treatment with a base is an essential step for galanthamine extraction. Scanning electron microscope (SEM) results also revealed that the desorption of N. pseudonarcissus alkaloids from the plant material rather than the solubility of the alkaloids in the scCO2 plays a major role in this scCO2 extraction. This extraction method has a good potential for industrial application.