China
Africa
Explore chapters and articles related to this topic
Atomic-Scale Simulation of Tribological and Related Phenomena
Published in Bharat Bhushan, Handbook of Micro/Nano Tribology, 2020
Judith A. Harrison, Steven J. Stuart, Donald W. Brenner
The layering of these films had profound effects on other equilibrium properties. For example, Wang et al. (1993a) showed that the solvation force of n-octane thin films increased dramatically as the pore size decreased. Surface force apparatus experiments have also shown that the nature of the film has an effect on the solvation force. It is well known that linear alkane molecules tend to layer close to a surface. This layering gives rise to oscillations in the density profile (Christenson et al., 1989). While early experiments indicated that the surface force oscillations vanish for branched alkanes such as 2-methyloctadecane (Israelachvili et al., 1989), more recent experiments (Granick et al., 1995) have shown oscillations in the force profiles of branched hydrocarbon molecules containing a single-pendant methyl group that are similar to those of linear hydrocarbons. Wang et al. (1993a,b, 1994) carried out MD studies on confined n-octane and 2-methylheptane and reached a similar conclusion.
Evaluation of Methods Used to Generate and Characterize Jet Fuel Vapor and Aerosol for Inhalation Toxicology Studies
Published in Mark L. Witten, Errol Zeiger, Glenn D. Ritchie, Jet Fuel Toxicology, 2010
Raphaël T. Tremblay, Sheppard A. Martin, Jeffrey W. Fisher
This phenomenon of preferential evaporation leads to widely different exposure characteristics for different inhalation chambers, suggesting possible difficulty in comparing toxicology data reported by laboratories using different generation systems. Typically, at no point during the fuel exposure is the vapor or aerosol composition absolutely predictable in terms of representing the known neat fuel composition. Table 12.1 presents an example of the measured composition of vapor and aerosol phases generated for a JP-8 inhalation exposure, and is compared to the composition of neat JP-8. In this example, the volatile compounds (methylcyclohexane, toluene, 2-methylheptane, and octane) account for nearly 10% of the vapor phase, although they only represent about 3% of the neat fuel. A similar but reverse discordance between the neat fuel composition and aerosol droplet composition is observed for low vapor pressure compounds in the aerosol. The last six compounds in Table 12.1 (dodecane and other larger-molecular-weight compounds) account for more than 14% of the aerosol composition, while they account for only about 8.5% of the neat fuel.
Fluid Properties
Published in W. M. Haynes, David R. Lide, Thomas J. Bruno, CRC Handbook of Chemistry and Physics, 2016
W. M. Haynes, David R. Lide, Thomas J. Bruno
Name 1-Isopropyl-4-methylbenzene Mercury Mesityl oxide Methanol 2-Methoxyethanol Methyl acetate 2-Methylaniline 3-Methylaniline Methyl benzoate 2-Methyl-1,3-butadiene Methyl butanoate 2-Methyl-2-butanol N-Methylformamide Methyl formate 2-Methylheptane 3-Methylheptane 2-Methylhexane 3-Methylhexane Methyl hexanoate Methyl methacrylate Methyloxirane 2-Methylpentane 3-Methylpentane Methyl pentanoate Methyl propanoate 2-Methyl-2-propanol N-Methyl-2-pyrrolidinone Nitrobenzene Nitroethane Nitromethane 1-Nitropropane Nonane Nonanoic acid 1-Nonanol 1-Nonene Octadecane Octane Octanoic acid 1-Octanol 2-Octanone 1-Octene Octyl butanoate Octyl propanoate Paraldehyde Pentanal Pentane 1,5-Pentanediol 2,4-Pentanedione Pentanoic acid 1-Pentanol 2-Pentanone 3-Pentanone 1-Pentene Pentyl acetate Pentylbenzene Pentyl propanoate 1-Pentyne Per uorocyclobutane Per uoroheptane Per uorohexane Mol. Form. C10H14 Hg C6H10O CH4O C3H8O2 C3H6O2 C7H9N C7H9N C8H8O2 C5H8 C5H10O2 C5H12O C2H5NO C2H4O2 C8H18 C8H18 C7H16 C7H16 C7H14O2 C5H8O2 C3H6O C6H14 C6H14 C6H12O2 C4H8O2 C4H10O C5H9NO C6H5NO2 C2H5NO2 CH3NO2 C3H7NO2 C9H20 C9H18O2 C9H20O C9H18 C18H38 C8H18 C8H16O2 C8H18O C8H16O C8H16 C12H24O2 C11H22O2 C6H12O3 C5H10O C5H12 C5H12O2 C5H8O2 C5H10O2 C5H12O C5H10O C5H10O C5H10 C7H14O2 C11H16 C8H16O2 C5H8 C4F8 C7F16 C6F14 (-25 ºC)/ W m-1 K-1 0.132 7.85 0.170 0.218 0.174 (-0 ºC)/ W m-1 K-1 0.127 8.175 0.163 0.210 0.164 (25 ºC)/ W m-1 K-1 0.122 8.514 0.156 0.202 0.190 0.153 0.162 0.161 0.147 0.119 0.140 0.116 0.203 0.187 0.1139 0.1149 0.1105 0.1112 0.136 0.147 0.171 0.1050 0.1064 0.138 0.141 0.112 0.167 0.149 0.173 0.204 0.152 0.1269 0.150 0.159 0.123 0.1244 0.146 0.158 0.135 0.126 0.139 0.135 0.130 0.139 0.1113 0.222 0.154 0.140 0.150 0.142 0.144 0.116 0.134 0.130 0.138 0.127 0.063 0.060 0.065 (50 ºC)/ W m-1 K-1 0.117 8.842 0.149 0.195 0.180 0.143 (75 ºC)/ W m-1 K-1 0.112 9.161 0.142 0.189 0.170 0.133 (100 ºC)/ W m-1 K-1 0.107 9.475 0.134 0.182 0.122
A Novel Group-based Correlation for the Ignition Delay Time of Paraffinic-type Fuels
Published in Combustion Science and Technology, 2022
Juan J. Hernández, Magín Lapuerta, Alexis Cova-Bonillo
Wang et al. (2013) found no substantial differences between ignition delays for 3-methylheptane, 2-methylheptane and n-octane at high temperatures, which was associated with the similarity of intermediates formed during the initiation phase. However, at NTC and low temperatures, ignition delay values were substantially different and according to their RONs (37, 22, and 19, respectively). Sarathy et al. (2011a) explained this behavior by the action of the methyl on the isomerization rate of O2QOOH• that lead to chain branching. The difference in the position of the methyl group establishes an imbalance between two possible reaction paths: chain branching and cyclic ether formation. Tanaka et al. (2003) highlighted the relation between the formation of 6-member low strain C-C-C-O-O-H rings (which are characteristic of two-stage ignition) and the structure -CH2-CH2-CH2-, with relatively short ignition delays time and burn rates.
Pyrolysis reactivity and volatile organic compounds of six Chinese low-rank coals analyzed by TG and Py-GC/MS
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2021
Y.-P. Zhao, X.-G. Si, F.-P. Wu, J. Yan, X. Fan, R.-Y. Wang, X.-Y. Wei
As shown in Table S1, a series of n-alkane from C7 to C29 and four branched alkanes, i.e. 2,4-dimethylhexane, 3-ethyl-2-methylheptane, 2-methylpentadecane, and 2,6,10,14-tetramethylhexadecane are detected in the VOCs of the LRCs. The total relative contents (RCs) of alkanes in the VOCs from the sub-bituminous coals are more than 29%, which is obvious higher than those from the lignite. Moreover, the branched alkanes were only detected in the VOCs of the sub-bituminous coals. Similar to alkanes, most of the alkenes detected in the VOCs of the LRCs are n-alkenes (Table S2). The total RCs of alkenes in the VOCs from the sub-bituminous coals are also higher than those from the lignite, suggesting that the amount of aliphatic C = C component in the sub-bituminous is more than that in the lignite. Additionally, the RCs of alkanes and alkenes in the VOCs of XH are obviously lower than those of other lignite, indicating that there are less aliphatic side chains in the macromolecular structure of XH than those of XLT and BYH. Only a few of cycloalkanes were released from the LRCs during pyrolysis (Table S3).