The Experts below are selected from a list of 1140 Experts worldwide ranked by ideXlab platform
Leif Poll - One of the best experts on this subject based on the ideXlab platform.
-
determination of odor active aroma compounds in freshly cut leek allium ampeloprasum var bulga and in long term stored frozen unblanched and blanched leek slices by gas chromatography olfactometry analysis
Journal of Agricultural and Food Chemistry, 2004Co-Authors: Ghita Studsgaard Nielsen, Leif PollAbstract:The odor active compounds in freshly cut leek slices and in blanched and unblanched leek slices stored for 12 months were investigated by a detection frequency method. Fifteen judges were evaluating the three samples randomized. The most important aroma compounds in the freshly cut leek slices were dipropyl disulfide, methyl propenyl disulfide, Pentanal, decanal, and propyl propenyl disulfide in order of priority. When stored frozen and unblanched for 12 months, the aroma composition changed and the most important compounds became Pentanal, decanal, 2,5-dimethyl furan, unknown compound I, and dipropyl disulfide. Blanching before freezing prevented to some degree these changes but also reduced the perceived intensity of the aroma compounds. The most important aroma compounds in the blanched sample were dipropyl disulfide, unknown compound I, Pentanal, 2,5-dimethyl furan, and propyl propenyl disulfide. Keywords: Leek; GC-O; aroma compounds; frozen storage; blanching
-
determination of odor active aroma compounds in freshly cut leek allium ampeloprasum var bulga and in long term stored frozen unblanched and blanched leek slices by gas chromatography olfactometry analysis
Journal of Agricultural and Food Chemistry, 2004Co-Authors: Ghita Studsgaard Nielsen, Leif PollAbstract:The odor active compounds in freshly cut leek slices and in blanched and unblanched leek slices stored for 12 months were investigated by a detection frequency method. Fifteen judges were evaluating the three samples randomized. The most important aroma compounds in the freshly cut leek slices were dipropyl disulfide, methyl propenyl disulfide, Pentanal, decanal, and propyl propenyl disulfide in order of priority. When stored frozen and unblanched for 12 months, the aroma composition changed and the most important compounds became Pentanal, decanal, 2,5-dimethyl furan, unknown compound I, and dipropyl disulfide. Blanching before freezing prevented to some degree these changes but also reduced the perceived intensity of the aroma compounds. The most important aroma compounds in the blanched sample were dipropyl disulfide, unknown compound I, Pentanal, 2,5-dimethyl furan, and propyl propenyl disulfide.
Ghita Studsgaard Nielsen - One of the best experts on this subject based on the ideXlab platform.
-
determination of odor active aroma compounds in freshly cut leek allium ampeloprasum var bulga and in long term stored frozen unblanched and blanched leek slices by gas chromatography olfactometry analysis
Journal of Agricultural and Food Chemistry, 2004Co-Authors: Ghita Studsgaard Nielsen, Leif PollAbstract:The odor active compounds in freshly cut leek slices and in blanched and unblanched leek slices stored for 12 months were investigated by a detection frequency method. Fifteen judges were evaluating the three samples randomized. The most important aroma compounds in the freshly cut leek slices were dipropyl disulfide, methyl propenyl disulfide, Pentanal, decanal, and propyl propenyl disulfide in order of priority. When stored frozen and unblanched for 12 months, the aroma composition changed and the most important compounds became Pentanal, decanal, 2,5-dimethyl furan, unknown compound I, and dipropyl disulfide. Blanching before freezing prevented to some degree these changes but also reduced the perceived intensity of the aroma compounds. The most important aroma compounds in the blanched sample were dipropyl disulfide, unknown compound I, Pentanal, 2,5-dimethyl furan, and propyl propenyl disulfide. Keywords: Leek; GC-O; aroma compounds; frozen storage; blanching
-
determination of odor active aroma compounds in freshly cut leek allium ampeloprasum var bulga and in long term stored frozen unblanched and blanched leek slices by gas chromatography olfactometry analysis
Journal of Agricultural and Food Chemistry, 2004Co-Authors: Ghita Studsgaard Nielsen, Leif PollAbstract:The odor active compounds in freshly cut leek slices and in blanched and unblanched leek slices stored for 12 months were investigated by a detection frequency method. Fifteen judges were evaluating the three samples randomized. The most important aroma compounds in the freshly cut leek slices were dipropyl disulfide, methyl propenyl disulfide, Pentanal, decanal, and propyl propenyl disulfide in order of priority. When stored frozen and unblanched for 12 months, the aroma composition changed and the most important compounds became Pentanal, decanal, 2,5-dimethyl furan, unknown compound I, and dipropyl disulfide. Blanching before freezing prevented to some degree these changes but also reduced the perceived intensity of the aroma compounds. The most important aroma compounds in the blanched sample were dipropyl disulfide, unknown compound I, Pentanal, 2,5-dimethyl furan, and propyl propenyl disulfide.
Chenglong Tang - One of the best experts on this subject based on the ideXlab platform.
-
The effect of pentanol addition on the particulate emission characteristics of a biodiesel operated diesel engine
Fuel, 2017Co-Authors: Ke Yang, Chun Shun Cheung, Long Wei, Chenglong TangAbstract:Abstract In the present study, combustion performance and the physical and chemical characteristics of soot particles from a DI diesel engine were studied. The engine was fueled with n -pentanol mixed with biodiesel at 15% and 30% by volume and operated at 1800 rpm under three engine loads (20%, 50% and 80% load). In comparison with pure biodiesel, the pentanol-biodiesel blends lead to delayed start of combustion and shortened combustion duration. The particle number concentrations of all size groups are reduced for biodiesel-pentanol blends in all the tested conditions, due to longer ignition delay time, lower viscosity and boiling point, and higher oxygen content of pentanol. The brake specific elemental carbon (EC) emissions of biodiesel were found to be lower compared to diesel and after adding pentanol in biodiesel, the EC emissions further decrease. While for organic carbon (OC) emissions, biodiesel and diesel are at similar level under the tested engine loads, and the blends show a higher fraction of OC at low and medium engine loads. The blended fuel with higher proportion of pentanol gives lower total particle-phase PAHs emissions and also a lower benzo[a]pyrene equivalent (BaP eq ) compared to pure biodiesel under the tested engine loads.
-
Laminar Flame Speeds and Kinetic Modeling of n-Pentanol and Its Isomers
Energy & Fuels, 2015Co-Authors: Chenglong Tang, Yu Cheng, Li GuanAbstract:A comprehensive experimental and computational study was conducted on the laminar combustion characteristics and chemical kinetics of four pentanol isomer–air mixtures (n-pentanol, 3-methyl-1-butanol, 2-methyl-1-butanol, and 2-methyl-2-butanol). Experiments were performed at the equivalence ratios ranging from 0.6 to 1.8, three initial temperatures (393, 433, and 473 K), and four pressures (0.1, 0.25, 0.5, and 0.75 MPa) using outwardly propagating flames. Results show that the laminar flame speeds of the four pentanol isomers decrease in the order of n-pentanol, 2-methyl-1-butanol, 3-methyl-1-butanol, and 2-methyl-2-butanol. The most significant differences among the isomers are observed around the stoichiometric mixture. Simulations on the laminar flame speeds of n-pentanol and 3-methyl-1-butanol were respectively performed using the model of Heufer et al. and Sarathy et al. Comparisons between the simulations and experimental data show the n-pentanol model yields satisfactory agreement with the data at ...
-
high temperature ignition delay times of c5 primary alcohols
Combustion and Flame, 2013Co-Authors: Chenglong Tang, Jiaxiang ZhangAbstract:Abstract Ignition delay times of the three C5 primary alcohol isomers (n-pentanol, iso-pentanol and 2-methyl-1-butanol) were measured behind reflected shock waves. Experiments were conducted in the temperature range of 1100–1500 K, pressures of 1.0 and 2.6 atm, equivalence ratios of 0.25, 0.5 and 1.0, and O2 concentration in the fuel/O2/Ar mixtures varying from 3.75% to 15%. Measurements show that the ignition delay time and the global activation energy of the three isomers both decrease in the order of iso-pentanol, 2-methyl-1-butanol, and n-pentanol. Chemical kinetic mechanisms for n-pentanol (Mech NP) and iso-pentanol (Mech IP), recently developed by Dagaut and co-workers, were used to model the respective ignition delay times. Results show that Mech NP yields close agreement at the equivalence ratio of 0.25, but the agreement is moderated with increasing equivalence ratio. Mech IP yields fairly close agreements at relatively higher temperatures but over-predicts the measurements by 50% at relatively lower temperatures for the three equivalence ratios studied. A new 2-methyl-1-butanol high temperature mechanism was proposed and validated against the ignition delay data. Sensitivity analysis for both n-pentanol and iso-pentanol showed the dominance of small radical reactions. Reaction pathway analysis aided further scrutiny of the fuel-specific reactions in Mech NP, leading to refinement of the kinetic model, and improved agreement between the predicted and measured ignition delay times as well as the jet-stirred reactor results.
-
high temperature ignition delay times of c5 primary alcohols
Combustion and Flame, 2013Co-Authors: Chenglong Tang, Jiaxiang ZhangAbstract:Abstract Ignition delay times of the three C5 primary alcohol isomers (n-pentanol, iso-pentanol and 2-methyl-1-butanol) were measured behind reflected shock waves. Experiments were conducted in the temperature range of 1100–1500 K, pressures of 1.0 and 2.6 atm, equivalence ratios of 0.25, 0.5 and 1.0, and O2 concentration in the fuel/O2/Ar mixtures varying from 3.75% to 15%. Measurements show that the ignition delay time and the global activation energy of the three isomers both decrease in the order of iso-pentanol, 2-methyl-1-butanol, and n-pentanol. Chemical kinetic mechanisms for n-pentanol (Mech NP) and iso-pentanol (Mech IP), recently developed by Dagaut and co-workers, were used to model the respective ignition delay times. Results show that Mech NP yields close agreement at the equivalence ratio of 0.25, but the agreement is moderated with increasing equivalence ratio. Mech IP yields fairly close agreements at relatively higher temperatures but over-predicts the measurements by 50% at relatively lower temperatures for the three equivalence ratios studied. A new 2-methyl-1-butanol high temperature mechanism was proposed and validated against the ignition delay data. Sensitivity analysis for both n-pentanol and iso-pentanol showed the dominance of small radical reactions. Reaction pathway analysis aided further scrutiny of the fuel-specific reactions in Mech NP, leading to refinement of the kinetic model, and improved agreement between the predicted and measured ignition delay times as well as the jet-stirred reactor results.
Jiaxiang Zhang - One of the best experts on this subject based on the ideXlab platform.
-
high temperature ignition delay times of c5 primary alcohols
Combustion and Flame, 2013Co-Authors: Chenglong Tang, Jiaxiang ZhangAbstract:Abstract Ignition delay times of the three C5 primary alcohol isomers (n-pentanol, iso-pentanol and 2-methyl-1-butanol) were measured behind reflected shock waves. Experiments were conducted in the temperature range of 1100–1500 K, pressures of 1.0 and 2.6 atm, equivalence ratios of 0.25, 0.5 and 1.0, and O2 concentration in the fuel/O2/Ar mixtures varying from 3.75% to 15%. Measurements show that the ignition delay time and the global activation energy of the three isomers both decrease in the order of iso-pentanol, 2-methyl-1-butanol, and n-pentanol. Chemical kinetic mechanisms for n-pentanol (Mech NP) and iso-pentanol (Mech IP), recently developed by Dagaut and co-workers, were used to model the respective ignition delay times. Results show that Mech NP yields close agreement at the equivalence ratio of 0.25, but the agreement is moderated with increasing equivalence ratio. Mech IP yields fairly close agreements at relatively higher temperatures but over-predicts the measurements by 50% at relatively lower temperatures for the three equivalence ratios studied. A new 2-methyl-1-butanol high temperature mechanism was proposed and validated against the ignition delay data. Sensitivity analysis for both n-pentanol and iso-pentanol showed the dominance of small radical reactions. Reaction pathway analysis aided further scrutiny of the fuel-specific reactions in Mech NP, leading to refinement of the kinetic model, and improved agreement between the predicted and measured ignition delay times as well as the jet-stirred reactor results.
-
high temperature ignition delay times of c5 primary alcohols
Combustion and Flame, 2013Co-Authors: Chenglong Tang, Jiaxiang ZhangAbstract:Abstract Ignition delay times of the three C5 primary alcohol isomers (n-pentanol, iso-pentanol and 2-methyl-1-butanol) were measured behind reflected shock waves. Experiments were conducted in the temperature range of 1100–1500 K, pressures of 1.0 and 2.6 atm, equivalence ratios of 0.25, 0.5 and 1.0, and O2 concentration in the fuel/O2/Ar mixtures varying from 3.75% to 15%. Measurements show that the ignition delay time and the global activation energy of the three isomers both decrease in the order of iso-pentanol, 2-methyl-1-butanol, and n-pentanol. Chemical kinetic mechanisms for n-pentanol (Mech NP) and iso-pentanol (Mech IP), recently developed by Dagaut and co-workers, were used to model the respective ignition delay times. Results show that Mech NP yields close agreement at the equivalence ratio of 0.25, but the agreement is moderated with increasing equivalence ratio. Mech IP yields fairly close agreements at relatively higher temperatures but over-predicts the measurements by 50% at relatively lower temperatures for the three equivalence ratios studied. A new 2-methyl-1-butanol high temperature mechanism was proposed and validated against the ignition delay data. Sensitivity analysis for both n-pentanol and iso-pentanol showed the dominance of small radical reactions. Reaction pathway analysis aided further scrutiny of the fuel-specific reactions in Mech NP, leading to refinement of the kinetic model, and improved agreement between the predicted and measured ignition delay times as well as the jet-stirred reactor results.
Yuvarajan Devarajan - One of the best experts on this subject based on the ideXlab platform.
-
emission and performance analysis on the effect of exhaust gas recirculation in alcohol biodiesel aspirated research diesel engine
Environmental Science and Pollution Research, 2018Co-Authors: Arulprakasajothi Mahalingam, Dinesh Babu Munuswamy, Yuvarajan Devarajan, Santhanakrishnan RadhakrishnanAbstract:In this study, the effect of blending pentanol to biodiesel derived from mahua oil on emissions and performance pattern of a diesel engine under exhaust gas recirculation (EGR) mode was examined and compared with diesel. The purpose of this study is to improve the feasibility of employing biofuels as a potential alternative in an unmodified diesel engine. Two pentanol-biodiesel blends denoted as MOBD90P10 and MOBD80P20 which matches to 10 and 20 vol% of pentanol in biodiesel, respectively, were used as fuel in research engine at 10 and 20% EGR rates. Pentanol is chosen as a higher alcohol owing to its improved in-built properties than the other first-generation alcohols such as ethanol or methanol. Experimental results show that the pentanol and biodiesel blends (MOBD90P10 and MOBD80P20) have slightly higher brake thermal efficiency (0.2–0.4%) and lower brake-specific fuel consumption (0.6 to 1.1%) than that of neat biodiesel (MOBD100) at all engine loads. Nitrogen oxide (NOx) emission and smoke emission are reduced by 3.3–3.9 and 5.1–6.4% for pentanol and biodiesel blends compared to neat biodiesel. Introduction of pentanol to biodiesel reduces the unburned hydrocarbon (2.1–3.6%) and carbon monoxide emissions (3.1–4.2%) considerably. In addition, at 20% EGR rate, smoke, NOX emissions, and BTE drop by 7.8, 5.1, and 4.4% respectively. However, CO, HC emissions, and BSFC increased by 2.1, 2.8, and 3.8%, respectively, when compared to 0% EGR rate.
-
emissions analysis on diesel engine fuelled with cashew nut shell biodiesel and pentanol blends
Environmental Science and Pollution Research, 2017Co-Authors: Yuvarajan Devarajan, Dinesh Babu Munuswamy, Beemkumar NagappanAbstract:The present work is intended to investigate the emission characteristics of neat cashew nut shell methyl ester (CNSME100) by adding pentanol at two different proportions and compared with the baseline diesel. CNSME100 is prepared by the conventional transesterification process. CNSME100 is chosen due to its non-edible nature. Pentanol is chosen as an additive because of its higher inbuilt oxygen content and surface to volume ratio which reduces the drawbacks of neat CNSME100. Emission characteristics were carried out in single cylinder naturally aspirated CI engine fuelled with neat cashew nut shell methyl ester (CNSME), cashew nut shell methyl ester and pentanol by 10% volume (CNSME90P10), cashew nut shell methyl ester and pentanol by 20% volume (CNSME80P20), and diesel. This work also aims to investigate the feasibility of operating an engine fuelled with neat methyl ester and alcohol blends. Experimental results showed that by blending higher alcohol to neat cashew nut shell methyl ester reduces the emissions significantly. It is also found that the emission from neat methyl ester and pentanol blends is lesser than diesel at all loads.
-
Performance and emissions analysis on diesel engine fuelled with cashew nut shell biodiesel and pentanol blends
Korean Journal of Chemical Engineering, 2017Co-Authors: Yuvarajan Devarajan, Beemkumar Nagappan, Dinesh Babu MunuswamyAbstract:We studied the impact of blending pentanol, a next generation biofuel, with cashew nut shell biodiesel on its performance and emissions characteristics in a constant speed compression ignition engine. Our main objective was to reduce CO, HC, NO X and smoke emission when fueled with neat cashew nut shell biodiesel and the pentanol blends. Cashew nut shell oil is a byproduct from cashew nut industry. Since it is nonedible, it can be used as a promising alternative. Conventional transesterification process was used to convert the cashew nut shell oil into cashew nut shell biodiesel. Pentanol with 98.4% purity was used as an oxygenated additive. The experiment involved three test fuels: neat cashew nut shell biodiesel (C100), Pentanol blended with cashew nut shell biodiesel by 10% volume (C90P10) and Pentanol blended with cashew nut shell biodiesel by 20% volume (C80P20). The feasibility of using neat biofuel (without adding diesel) was also investigated. Experimental work concluded that the test fuels used in this study does not require any modification in engines. In addition, the combustion of fuels was smooth and there was no physical and visible damage in the engine components when fueled with cashew nut shell biodiesel and the pentanol blends. By adding 10% and 20% of pentanol to cashew nut shell biodiesel, significant reduction in CO, HC, NO X and smoke emission was observed. In addition, brake thermal efficiency increased marginally with slight reduction in brake specific fuel consumption.
-
Emissions analysis on second generation biodiesel
Frontiers of Environmental Science & Engineering, 2016Co-Authors: Yuvarajan Devarajan, Ravi Kumar Jayabal, Devanathan Ragupathy, Harish VenuAbstract:This work investigates the effect of adding pentanol with biodiesel derived from cashew nut shell on its emissions characteristics is conducted in stationery diesel engine. The main purpose of this work is intended to reduce the emissions by fuelling biodiesel derived from cashew nut shell and the pentanol blends. Cashew nut shell biodiesel is prepared by transesterification process. Oxygenated additive used in the work is Pentanol. The experiment is conducted using four test fuels such as, biodiesel derived from cashew nut shell (CNSBD), a fuel containing 90% cashew nut shell biodiesel and 10% pentanol (CNSBD90P10), a fuel containing 80% cashew nut shell biodiesel and 20% pentanol (CNSBD80P20) and neat diesel. Experimental work concluded that by adding 10% of pentanol to cashew nut shell biodiesel 10.1%, 2.6%, 5.1%and 2.1%reduction in CO, HC, NO_ x and Smoke emissions were observed respectively. Further by fueling with these blends, no modifications in engines were required.