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Published in Natan B. Vargaftik, Lev P. Filippov, Amin A. Tarzimanov, Evgenii E. Totskii, Yu. A. Gorshkov, Handbook of Thermal Conductivity of Liquids and Gases, 2020
Natan B. Vargaftik, Lev P. Filippov, Amin A. Tarzimanov, Evgenii E. Totskii, Yu. A. Gorshkov
2-Pentanone (methyl–propyl ketone, ethyl acetone) CH3CO(CH2)2CH3. Thermal conductivity of the saturated liquid as reported in refs. [183, 184, 207] is cited below: T,K…………280290300310320330340350360λ⋅103,W/(mK)147144141138136133130127124
Hole-Transporting-Free Perovskite Solar Cells
Published in Kunwu Fu, Anita Wing Yi Ho-Baillie, Hemant Kumar Mulmudi, Pham Thi Thu Trang, Perovskite Solar Cells, 2019
Kunwu Fu, Anita Wing Yi Ho-Baillie, Hemant Kumar Mulmudi, Pham Thi Thu Trang
Among various solvents tried, only 4-methyl-2-pentanone produced stable graphite suspensions after the centrifugation and does not dissolve the perovskite film. The treatment on the graphite film with NaBH4 prior to dispersing it into the 4-methyl-2-pentanone solvent was also done to reduce the oxidizing group on the surface of the film and hence increase the stability of the perovskite film underneath. The work also compared the difference between device with and without graphite layer as the hole extraction layer by electrochemical impedance spectroscopy. Upon incorporation of the graphite layer, the overall electron transfer resistance increased by more than an order of magnitude at zero bias but it dropped back to the previous values when 0.550 V bias was applied. The increase of the resistance was likely due to the initial formation of a poor electrical contact between the perovskite and graphite layers, which was later substantially improved when the bias was applied.
Oragnic Chemicals in the Environment
Published in Richard A. Larson, Eric J. Weber, Reaction Mechanisms in Environmental Organic Chemistry, 2018
Richard A. Larson, Eric J. Weber
Not as much work has been reported on atmospheric ketone concentrations. Acetone was present at 0.001 ppm in the air at Point Barrow, Alaska (Cavanagh et al., 1969) and also, at half that concentration or less, in air over the Atlantic (Penkett, 1982; Zhou and Mopper, 1990); it is also present at higher elevations (Arnold et al., 1986). Phenyl and higher cyclic ketones, a few C6-C18 aliphatic ketones, butanone, biacetyl and 4-methyl-2-pentanone have also been identified in ambient air (Kawamura and Kaplan, 1983; Ramdahl, 1983; Zhou and Mopper, 1990). Several quinones have been identified by Soxhlet extraction of atmospheric particulate material, including anthraquinone and more complex multi-ring compounds (Choudhury, 1982; Ramdahl et al., 1982). In addition, more than 40 other oxygenated PAHs including aldehydes, ketones, lactones, and anhydrides have also been characterized from airborne particle extracts (Choudhury, 1982; Newton et al., 1982; Ramdahl et al., 1982; König et al., 1983; Helmig et al., 1992). Fluorenone (11) and its alkyl homologs were particularly abundant in diesel emission particulate material.
Process analysis for biphasic dehydration of xylose: effects of solvents on the purification of furfural
Published in Biofuels, 2021
Jiwon An, Geunjeong Lee, Jeong-Myeong Ha, Myung-June Park
Conversion of the remaining xylose after biomass fermentation was addressed in this study to maximize the economics of biomass-based fuels. As an alternative to environmentally unfriendly solvents such as toluene and MIBK, 2-pentanone was suggested for use in a biphasic process. Despite the similar thermodynamic properties of the various solvents, 2-pentanone required a smaller number of separation columns, resulting in lower equipment costs and separation energy usage, than the other solvents, in cases of full solvent recovery. Because 2-pentanone can be further converted into hydrocarbon fuels in the downstream processes, the separation load can be decreased by allowing some solvent to remain with the desired product (furfural). This study clearly warrants further evaluation of 2-pentanone, one of the intermediates of the fuel production process, as a solvent to enhance the economics of a biphasic process.