The Experts below are selected from a list of 27711 Experts worldwide ranked by ideXlab platform
Dmitry Yu Murzin - One of the best experts on this subject based on the ideXlab platform.
-
hydrodeoxygenation of Stearic Acid and tall oil fatty Acids over ni alumina catalysts influence of reaction parameters and kinetic modelling
Chemical Engineering Journal, 2017Co-Authors: Klara Jenistova, Imane Hachemi, Paivi Makiarvela, Narendra Kumar, Markus Peurla, Libor Capek, Johan Warna, Dmitry Yu MurzinAbstract:Abstract Kinetics in the hydrodeoxygenation of Stearic Acid was investigated over Ni-γ-Al2O3 catalyst. The main variables were catalyst prereduction mode, reaction atmosphere and hydrogen pressure in the total pressure range of 7–30 bar. The results revealed that high conversion, 99% in 360 min and high selectivity to heptadecane, 97% were achieved at 300 °C under 30 bar total pressure. The yield of an intermediate hydrogenation product, stearyl alcohol increased with increasing hydrogen pressure as expected. Higher reaction rates and conversion levels were also achieved with the prereduced catalyst and carrying out the reaction in the presence of hydrogen. As a comparison to Stearic Acid, hydrodeoxygenation of tall oil fatty Acids, an industrial feedstock was successfully demonstrated with Ni-γ-Al2O3 under the same conditions. A kinetic model including the pressure effect was derived and applied for data with Ni-γ-Al2O3 as well as for Pd/C, Ni-H-Y-80 and Ni/SiO2 catalysts. The model described well the kinetic data.
-
catalytic deoxygenation of Stearic Acid in a continuous reactor over a mesoporous carbon supported pd catalyst
Energy & Fuels, 2009Co-Authors: Siswati Lestari, Paivi Makiarvela, Irina L Simakova, J N Beltramini, Heidi Bernas, Olga A Simakova, Rainer Sjoholm, Jukka Myllyoja, Dmitry Yu MurzinAbstract:Catalytic deoxygenation of neat Stearic Acid was studied at 360 °C under 10 bar argon or 5 vol % hydrogen in argon in a fixed-bed reactor (down flow) using mesoporous-supported Pd/C (Sibunit) beads as a catalyst. The results showed stable catalyst performance, giving about 15% conversion level of Stearic Acid. The main liquid-phase product was heptadecane, while the main gaseous products were CO and CO2.
-
catalytic deoxygenation of Stearic Acid and palmitic Acid in semibatch mode
Catalysis Letters, 2009Co-Authors: Paivi Makiarvela, Siswati Lestari, Irina L Simakova, J N Beltramini, Dmitry Yu MurzinAbstract:The deoxygenation experiments of different reactants, i.e., pure palmitic Acid, Stearic Acid, and a technical grade Stearic Acid containing a mixture of 59% of palmitic and 40% of Stearic Acid were successfully performed over 4 wt% Pd/C mesoporous catalyst at 300 °C under 17 bar of 5% H2 in argon. The main product in catalytic deoxygenation of saturated fatty Acids, C16 and C18, were aliphatic chain length hydrocarbons containing one less carbon than the corresponding Acid. Additionally it was found that the deoxygenation rates of different reactant were independent on carbon chain length of its fatty Acids.
-
heterogeneous catalytic deoxygenation of Stearic Acid for production of biodiesel
Industrial & Engineering Chemistry Research, 2006Co-Authors: Mathias Snare, Paivi Makiarvela, Iva Kubickova, And Kari Eranen, Dmitry Yu MurzinAbstract:A novel method for production of diesel-like hydrocarbons via catalytic deoxygenation of fatty Acid is discussed. The model compound Stearic Acid is deoxygenated to heptadecane, originating from the Stearic Acid alkyl chain. The deoxygenation reaction is carried out in a semibatch reactor under constant temperature and pressure, 300 °C and 6 bar, respectively. A thorough catalyst screening was performed to obtain the most promising metal and support combination. The catalysts were characterized by N2-physisorption, CO-chemisorption, and temperature-programmed desorption of hydrogen. A highly active and selective in the deoxygenation reaction of Stearic Acid carbon supported palladium catalyst converted Stearic Acid completely with >98% selectivity toward deoxygenated C17 products.
Hasan Uludag - One of the best experts on this subject based on the ideXlab platform.
-
formulation and delivery of sirna by oleic Acid and Stearic Acid modified polyethylenimine
Molecular Pharmaceutics, 2009Co-Authors: Aws Alshamsan, Azita Haddadi, Vanessa Incani, John Samuel, Afsaneh Lavasanifar, Hasan UludagAbstract:This study was conducted to formulate a nonviral delivery system for the delivery of small interfering RNA (siRNA) to B16 melanoma cells in vitro. For this purpose, oleic and Stearic Acid modified derivatives of branched polyethylenimine (PEI) were prepared and evaluated. The hydrophobically modified polymers increased siRNA condensation up to 3 folds as compared to the parent PEI. The modified PEIs exhibited up to 3-fold higher siRNA protection from degradation in fetal bovine serum as compared to the parent PEI. The formulated complexes were shown to enter B16 cells in a time-dependent fashion, reaching over 90% of the cells after 24 h, as compared to only 5% of the cells displaying siRNA uptake in the absence of any carrier. A proportional reduction in siRNA cell uptake was observed with reduced polymeric content in the formulations. When used to deliver various doses of siRNA to B16 cells, the modified PEIs were superior or comparable to some of the commercially available transfection agents; the hydrophobically modified polymers gave 3-fold increased siRNA delivery than the parent PEI, approximately 5-fold higher delivery than jetPEI and Metafectene, a comparable delivery to Lipofectamine 2000, but a 1.6-fold decreased delivery compared to INTERFERin, which was the most efficient reagent in our hands. Using an siRNA specific for integrin alpha(v), a dose-dependent decrease in integrin alpha(v) levels was demonstrated in B16 cells by flow cytometry, revealing a more pronounced reduction of integrin alpha(v) levels for oleic- and Stearic-Acid modified PEIs. The overall results suggested that the hydrophobically modified PEIs provide a promising delivery strategy for siRNA therapeutic applications.
-
formulation and delivery of sirna by oleic Acid and Stearic Acid modified polyethylenimine
Molecular Pharmaceutics, 2009Co-Authors: Aws Alshamsan, Azita Haddadi, Vanessa Incani, John Samuel, Afsaneh Lavasanifar, Hasan UludagAbstract:This study was conducted to formulate a nonviral delivery system for the delivery of small interfering RNA (siRNA) to B16 melanoma cells in vitro. For this purpose, oleic and Stearic Acid modified derivatives of branched polyethylenimine (PEI) were prepared and evaluated. The hydrophobically modified polymers increased siRNA condensation up to 3 folds as compared to the parent PEI. The modified PEIs exhibited up to 3-fold higher siRNA protection from degradation in fetal bovine serum as compared to the parent PEI. The formulated complexes were shown to enter B16 cells in a time-dependent fashion, reaching over 90% of the cells after 24 h, as compared to only 5% of the cells displaying siRNA uptake in the absence of any carrier. A proportional reduction in siRNA cell uptake was observed with reduced polymeric content in the formulations. When used to deliver various doses of siRNA to B16 cells, the modified PEIs were superior or comparable to some of the commercially available transfection agents; the hydr...
Anil N Netravali - One of the best experts on this subject based on the ideXlab platform.
-
characterization of Stearic Acid modified soy protein isolate resin and ramie fiber reinforced green composites
Composites Science and Technology, 2005Co-Authors: Preeti Lodha, Anil N NetravaliAbstract:Abstract The effects of Stearic Acid on the physical, tensile, moisture, thermal and micro-structural properties of the soy protein isolate (SPI)-based resin have been investigated. Fully biodegradable, environment-friendly, unidirectional, ramie fiber reinforced ‘green’ composites were also successfully fabricated using SPI and Stearic Acid modified SPI (MSPI) resins and characterized for their tensile and flexural properties. The fiber/resin interfacial shear strength was characterized using microbond technique. The mechanical and thermal properties and moisture resistance of the MSPI resin were significantly better than the SPI resin. It was observed that part of the Stearic Acid crystallized in SPI resin and that the crystallizability was affected by the glycerol added as a plasticizer. The replacement of glycerol with Stearic Acid did not affect the fiber/resin interfacial interaction. The ramie/MSPI composites showed significantly better mechanical properties compared to ramie/SPI composites. While the Young’s modulus of ramie/MSPI composites was closer to the theoretically calculated values, both composites had lower values than predicted. The ramie fiber/MSPI resin composites may be used as ‘green’ composites for certain indoor applications.
-
thermal and mechanical properties of environment friendly green plastics from Stearic Acid modified soy protein isolate
Industrial Crops and Products, 2005Co-Authors: Preeti Lodha, Anil N NetravaliAbstract:Abstract Most plastics, at present, are petroleum-based and do not degrade over many decades under normal environmental conditions. As a result, efforts towards developing environment-friendly and biodegradable ‘green’ plastics for various commercial applications have gained significant momentum in recent years. Soy protein isolate (SPI)-based ‘green’ plastics have been shown to suffer from high moisture sensitivity and low strength. These properties have limited their use in most commercial applications. They are also difficult to process into sheets without any plasticizer. The commonly used plasticizer, glycerol, tends to leach out over time producing time-dependent properties, which is highly undesirable for commercial applications. The objectives of the current research are to reduce the moisture sensitivity and simultaneously improve the tensile properties of SPI by incorporation of Stearic Acid without affecting its biodegradability. The effect of Stearic Acid and glycerol on the tensile and thermal properties of SPI has been characterized using various techniques to determine the interaction mechanisms between Stearic Acid and soy protein. Mechanical properties were characterized using Instron tensile tester. Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, differential scanning calorimetry (DSC), thermo-gravimetric analysis (TGA) and X-ray diffraction (XRD) techniques have been used to determine the effects of Stearic Acid and glycerol on the surface chemistry, thermal transitions and thermal degradation of the Stearic Acid modified SPI plastic (resin). The tensile test results show that Young’s modulus increased on increasing the Stearic Acid content, reaching the maximum value at about 25% (by weight of SPI powder) Stearic Acid. Further increase in Stearic Acid content from 25 to 30% led to a reduction in Young’s modulus. The moisture content, fracture stress, strain, and energy at break decreased steadily on increasing the Stearic Acid from 0 to 30% for SPI containing 30% glycerol. At 25% Stearic Acid content, the modulus and the fracture stress increased significantly, whereas the fracture strain, energy at break and the moisture content decreased on reducing glycerol content. Scanning electron microscopy photomicrographs of fractured surfaces showed a layered structure for Stearic Acid modified-SPI resin. TGA measurements showed that the thermal degradation of Stearic Acid modified-SPI resin initiated at higher temperature than the SPI resin. DSC scans indicated that Stearic Acid modified-SPI resin had a small degree of crystallinity, which was confirmed by X-ray diffraction patterns. Modifying SPI resin with Stearic Acid has been successful in obtaining better tensile and thermal properties as well as reduced moisture sensitivity without any processing problems.
Siswati Lestari - One of the best experts on this subject based on the ideXlab platform.
-
catalytic deoxygenation of Stearic Acid in a continuous reactor over a mesoporous carbon supported pd catalyst
Energy & Fuels, 2009Co-Authors: Siswati Lestari, Paivi Makiarvela, Irina L Simakova, J N Beltramini, Heidi Bernas, Olga A Simakova, Rainer Sjoholm, Jukka Myllyoja, Dmitry Yu MurzinAbstract:Catalytic deoxygenation of neat Stearic Acid was studied at 360 °C under 10 bar argon or 5 vol % hydrogen in argon in a fixed-bed reactor (down flow) using mesoporous-supported Pd/C (Sibunit) beads as a catalyst. The results showed stable catalyst performance, giving about 15% conversion level of Stearic Acid. The main liquid-phase product was heptadecane, while the main gaseous products were CO and CO2.
-
catalytic deoxygenation of Stearic Acid and palmitic Acid in semibatch mode
Catalysis Letters, 2009Co-Authors: Paivi Makiarvela, Siswati Lestari, Irina L Simakova, J N Beltramini, Dmitry Yu MurzinAbstract:The deoxygenation experiments of different reactants, i.e., pure palmitic Acid, Stearic Acid, and a technical grade Stearic Acid containing a mixture of 59% of palmitic and 40% of Stearic Acid were successfully performed over 4 wt% Pd/C mesoporous catalyst at 300 °C under 17 bar of 5% H2 in argon. The main product in catalytic deoxygenation of saturated fatty Acids, C16 and C18, were aliphatic chain length hydrocarbons containing one less carbon than the corresponding Acid. Additionally it was found that the deoxygenation rates of different reactant were independent on carbon chain length of its fatty Acids.
Aws Alshamsan - One of the best experts on this subject based on the ideXlab platform.
-
formulation and delivery of sirna by oleic Acid and Stearic Acid modified polyethylenimine
Molecular Pharmaceutics, 2009Co-Authors: Aws Alshamsan, Azita Haddadi, Vanessa Incani, John Samuel, Afsaneh Lavasanifar, Hasan UludagAbstract:This study was conducted to formulate a nonviral delivery system for the delivery of small interfering RNA (siRNA) to B16 melanoma cells in vitro. For this purpose, oleic and Stearic Acid modified derivatives of branched polyethylenimine (PEI) were prepared and evaluated. The hydrophobically modified polymers increased siRNA condensation up to 3 folds as compared to the parent PEI. The modified PEIs exhibited up to 3-fold higher siRNA protection from degradation in fetal bovine serum as compared to the parent PEI. The formulated complexes were shown to enter B16 cells in a time-dependent fashion, reaching over 90% of the cells after 24 h, as compared to only 5% of the cells displaying siRNA uptake in the absence of any carrier. A proportional reduction in siRNA cell uptake was observed with reduced polymeric content in the formulations. When used to deliver various doses of siRNA to B16 cells, the modified PEIs were superior or comparable to some of the commercially available transfection agents; the hydrophobically modified polymers gave 3-fold increased siRNA delivery than the parent PEI, approximately 5-fold higher delivery than jetPEI and Metafectene, a comparable delivery to Lipofectamine 2000, but a 1.6-fold decreased delivery compared to INTERFERin, which was the most efficient reagent in our hands. Using an siRNA specific for integrin alpha(v), a dose-dependent decrease in integrin alpha(v) levels was demonstrated in B16 cells by flow cytometry, revealing a more pronounced reduction of integrin alpha(v) levels for oleic- and Stearic-Acid modified PEIs. The overall results suggested that the hydrophobically modified PEIs provide a promising delivery strategy for siRNA therapeutic applications.
-
formulation and delivery of sirna by oleic Acid and Stearic Acid modified polyethylenimine
Molecular Pharmaceutics, 2009Co-Authors: Aws Alshamsan, Azita Haddadi, Vanessa Incani, John Samuel, Afsaneh Lavasanifar, Hasan UludagAbstract:This study was conducted to formulate a nonviral delivery system for the delivery of small interfering RNA (siRNA) to B16 melanoma cells in vitro. For this purpose, oleic and Stearic Acid modified derivatives of branched polyethylenimine (PEI) were prepared and evaluated. The hydrophobically modified polymers increased siRNA condensation up to 3 folds as compared to the parent PEI. The modified PEIs exhibited up to 3-fold higher siRNA protection from degradation in fetal bovine serum as compared to the parent PEI. The formulated complexes were shown to enter B16 cells in a time-dependent fashion, reaching over 90% of the cells after 24 h, as compared to only 5% of the cells displaying siRNA uptake in the absence of any carrier. A proportional reduction in siRNA cell uptake was observed with reduced polymeric content in the formulations. When used to deliver various doses of siRNA to B16 cells, the modified PEIs were superior or comparable to some of the commercially available transfection agents; the hydr...
