Journal articles: 'Dodecane'

1

Arai, Y., H. Ogino, M. Takeuchi, T. Kase, and Y. Nakajima. "Study on cleaning solvents using activated alumina in PUREX process." Proceedings in Radiochemistry 1, no. 1 (2011): 71–74. http://dx.doi.org/10.1524/rcpr.2011.0012.

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Abstract The PUREX process is used to extract uranium and plutonium from dissolved solutions (spent nuclear fuel liquor). The extractant is 30% tributyl phosphate in n-dodecane, which is known to be degradable by radiation and nitric acid. Tributyl phosphate degradation products can generally be washed in alkali solutions like sodium carbonate solution; however, it is more difficult to remove n-dodecane degradation products using this method. A method of cleaning solvents using activated alumina is discussed in this study. A degradation sample of 30% TBP/n-dodecane was prepared by irradiating (1.6 MGy) with a 60Co gamma-source. The degradation products were then qualitatively analyzed using a gas chromatography-mass spectrometer (GC-MS). After being irradiated the solvents were cleaned with activated alumina, and a phase separation test with performed in evaluating the cleaned solvent. This resulted in the discovery of a procedure for the removal of n-dodecane degradation products of dodecanol and dodecanone, with about 70% of the degradation products, and the phase separation performance could be clearly improved through use of activated alumina.

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Shen, Wei-Guo, and Arthur G. Williamson. "Enthalpies of mixing of ternary alkane mixtures with branched chain components." Canadian Journal of Chemistry 66, no. 4 (1988): 904–7. http://dx.doi.org/10.1139/v88-153.

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Measurements at 25 °C are reported for the enthalpies of mixing of 2-methyl pentane with n-dodecane and with each of three pseudo n-dodecanes prepared from equimolar mixtures of n-undecane + n-tridecane, n-decane + n-tetradecane, and n-octane + n-hexadecane respectively. Measurements for mixtures of the equimolar decane + tetradecane mixture with each of the other three branched hexane isomers are also reported. The results are compared with the work of Benson and co-workers for binary mixtures of n-dodecane with the same hexanes. The deviations of 1–2% from the principle of congruence are similar to those reported previously for the ternary n-alkane mixtures.

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Ratajczak, Andreas, Walter Geißdörfer, and Wolfgang Hillen. "Expression of Alkane Hydroxylase fromAcinetobacter sp. Strain ADP1 Is Induced by a Broad Range of n- Alkanes and Requires the Transcriptional Activator AlkR." Journal of Bacteriology 180, no. 22 (1998): 5822–27. http://dx.doi.org/10.1128/jb.180.22.5822-5827.1998.

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ABSTRACT In Acinetobacter sp. strain ADP1, alkane degradation depends on at least five essential genes. rubAB andxcpR are constitutively transcribed. Here we describe inducible transcription of alkM, which strictly depends on the presence of the transcriptional activator AlkR. alkRitself is expressed at a low level, while a chromosomally locatedalkM::lacZ fusion is inducible by middle-chain-length alkanes from heptane to undecane, which do not support growth of ADP1, and by long-chain-length alkanes from dodecane to octadecane, which are used as sources of carbon and energy. The putative AlkM substrate 1-dodecene is also an effective inducer. Products of alkane hydroxylase activity like 1-dodecanol prevent induction of alkM expression. alkM is expressed only in stationary phase, suggesting its dependence on at least one other regulatory mechanism.

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Pérez Ávila, Alan D., Sneyder Rodríguez-Barona, and Javier Fontalvo-Alzate. "Molecular toxicity of potential liquid membranes for lactic acid removal from fermentation broths using Lactobacillus casei ATCC 393." DYNA 85, no. 207 (2018): 360–66. http://dx.doi.org/10.15446/dyna.v85n207.72374.

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Toxic effects of extractants and carriers of specific microorganisms must be taken into account before using them with hybrid fermentation processes that are combined with liquid membranes or liquid-liquid extraction. In the current research three extractants (trioctylamine, tri-iso-octylamine and Aliquat 336), three diluents (dodecane, dodecanol, and oleyl alcohol) and two mixtures (extractant/diluent) were tested for molecular toxicity on the bacteria Lactobacillus casei ATCC 393 as potential components of a liquid membrane or a liquid-liquid extraction process for lactic acid removal in an intensified fermentation process. Glucose consumption, lactic acid production, and cell growth were used as toxicity indicators. Physical properties of extractants and diluents were related to the molecular toxicity on the microorganism. These results show that mixtures of tri-iso-octylamine/dodecane and trioctylamine/dodecane at a proportion of 1:9 v/v have great potential to be used in liquid membranes or liquid-liquid extraction processes on hybrid fermentations with Lactobacillus casei ATCC 393.

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Plesnar, Zofia, and Andrzej Bylicki. "(Solid + liquid) equilibria in (dodecan-1-ol + dodecane)." Journal of Chemical Thermodynamics 25, no. 12 (1993): 1447–52. http://dx.doi.org/10.1006/jcht.1993.1146.

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Whyte, Lyle G., Jalal Hawari, Edward Zhou, Luc Bourbonnière, William E. Inniss, and Charles W. Greer. "Biodegradation of Variable-Chain-Length Alkanes at Low Temperatures by a Psychrotrophic Rhodococcussp." Applied and Environmental Microbiology 64, no. 7 (1998): 2578–84. http://dx.doi.org/10.1128/aem.64.7.2578-2584.1998.

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ABSTRACT The psychrotroph Rhodococcus sp. strain Q15 was examined for its ability to degrade individual n-alkanes and diesel fuel at low temperatures, and its alkane catabolic pathway was investigated by biochemical and genetic techniques. At 0 and 5°C, Q15 mineralized the short-chain alkanes dodecane and hexadecane to a greater extent than that observed for the long-chain alkanes octacosane and dotriacontane. Q15 utilized a broad range of aliphatics (C10 to C21 alkanes, branched alkanes, and a substituted cyclohexane) present in diesel fuel at 5°C. Mineralization of hexadecane at 5°C was significantly greater in both hydrocarbon-contaminated and pristine soil microcosms seeded with Q15 cells than in uninoculated control soil microcosms. The detection of hexadecane and dodecane metabolic intermediates (1-hexadecanol and 2-hexadecanol and 1-dodecanol and 2-dodecanone, respectively) by solid-phase microextraction–gas chromatography-mass spectrometry and the utilization of potential metabolic intermediates indicated that Q15 oxidizes alkanes by both the terminal oxidation pathway and the subterminal oxidation pathway. Genetic characterization by PCR and nucleotide sequence analysis indicated that Q15 possesses an aliphatic aldehyde dehydrogenase gene highly homologous to the Rhodococcus erythropolis thcA gene. Rhodococcus sp. strain Q15 possessed two large plasmids of approximately 90 and 115 kb (shown to mediate Cd resistance) which were not required for alkane mineralization, although the 90-kb plasmid enhanced mineralization of some alkanes and growth on diesel oil at both 5 and 25°C.

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Cruz-Barrios, Eliandreina, and German Urbina-Villalba. "INFLUENCE OF CREAMING AND RIPENING ON THE AGGREGATION RATE OF NON-IONIC DODECANE-IN-WATER NANOEMULSIONS." REVISTA DEL CENTRO DE ESTUDIOS INTERDISCIPLINARIOS DE LA FISICA (RCEIF) 3 (December 1, 2014): 22–29. https://doi.org/10.5281/zenodo.5565599.

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The possible influence of creaming during the measurement of the aggregation rate of dodecane-in-water nanoemulsions stabilized with Brij 30 is explored. For this purpose additional emulsions made with a neutral-buoyancy oil (bromo- dodecane) and mixtures of dodecane and Br-dodecane with squalene were synthesized. It is concluded that when the effect of ripening is suppressed, the influence of buoyancy on the evaluation of the flocculation rate is negligible. In the absence of squalene, ripening is present, and a sizeable difference in the flocculation rate of dodecane and bromo- dodecane is observed. However, this difference is not caused by the effect of gravity.

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Zhou, Weijian, Song Zhou, Hongyuan Xi, Majed Shreka, and Zhao Zhang. "Chemical Kinetic Study on Dual-Fuel Combustion: The Ignition Properties of n-Dodecane/Methane Mixture." International Journal of Chemical Engineering 2021 (November 22, 2021): 1–17. http://dx.doi.org/10.1155/2021/7100812.

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The natural gas (NG)/diesel dual-fuel engine has attracted extensive attention in recent years, and the influence of ignition delay on the engine is very important. Therefore, the research on the ignition delay of NG/diesel dual fuel is of great significance. In this work, a simplified n-dodecane mechanism was used to study the effect of methane mixture ratio on the n-dodecane ignition process. The results showed that the ignition delay time increased with the increase of methane content by changing the mixing ratio of methane and n-dodecane. However, the effect of methane on the ignition delay time gradually decreases when the content of the n-dodecane mixing ratio is greater than 50%. It was also found that with the increase of n-dodecane content, the reduction degree of the ignition delay time of the whole reaction system decreased and the negative temperature coefficient (NTC) behavior increased. Moreover, when the initial pressure increased from 20 bar to 60 bar, the thermal effect of methane also increases from 7.03% to 9.55%. The relationship between ignition characteristics of methane-n-dodecane and temperature was studied by changing the initial temperature. Furthermore, the evolution of species in the ignition process of the whole reaction system was analyzed, and the decomposition of n-dodecane first occurs in the reaction n-C12H26 + O2 = R + HO2 to form R and free radicals; however, the reaction CH4 + OH = CH3 + H2O dominates with the increase of the methane mixing ratio and inhibits the ignition process. Through the analysis of reaction paths, sensitivity, and rates of production and consumption of methane/n-dodecane, it was explained how n-dodecane accelerates methane ignition through the rapidly formed free radicals.

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Yang, Xin, Hua Zhong, Guansheng Liu, Lili Huo, and Zonghua Wang. "Influence of Sub-CMC Rhamnolipid Flushing on the Mobilization and Solubilization of Residual Dodecane in Saturated Porous Media." Water 16, no. 21 (2024): 3152. http://dx.doi.org/10.3390/w16213152.

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The potential of monorhamnolipid (monoRL) biosurfactant to enhance the removal of residual dodecane from a porous medium was investigated under monoRL concentration varying from sub-CMC to hyper-CMC conditions by one-dimension column experiments. In the immiscible displacement experiment, 76% of the total volume of dodecane is removed by flushing of 150 μM monoRL solution. The solubilization of dodecane could be enhanced by rhamnolipid even at monorhamnolipid concentrations as low as 50 μM/L. The higher solubilization concentration (500 μM/L) of monoRL solution results in higher solubilized dodecane concentration (160 μM/L) due to the larger quantity of micelle formation. Compared to solubilization, immiscible displacement, or mobilization, is far more effective in removing residual dodecane. The interfacial partitioning tracer tests (IPTT) method is applied to measure the variation in specific dodecane-water interface areas (Anw). The results showed that the flushing of monoRL increased the Anw from 2.04 to 3.54 cm2/cm3. This investigation implies that low-concentration monorhamnolipid flushing and subsequent micelle solubilization is an economic method to remediate NAPL-contaminated fields.

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10

Ivanova, Anastasia A., Olesya I. Sazonova, Anton N. Zvonarev, et al. "Genome Analysis and Physiology of Pseudomonas sp. Strain OVF7 Degrading Naphthalene and n-Dodecane." Microorganisms 11, no. 8 (2023): 2058. http://dx.doi.org/10.3390/microorganisms11082058.

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The complete genome of the naphthalene- and n-alkane-degrading strain Pseudomonas sp. strain OVF7 was collected and analyzed. Clusters of genes encoding enzymes for the degradation of naphthalene and n-alkanes are localized on the chromosome. Based on the Average Nucleotide Identity and digital DNA–DNA Hybridization compared with type strains of the group of fluorescent pseudomonads, the bacterium studied probably belongs to a new species. Using light, fluorescent, and scanning electron microscopy, the ability of the studied bacterium to form biofilms of different architectures when cultured in liquid mineral medium with different carbon sources, including naphthalene and n-dodecane, was demonstrated. When grown on a mixture of naphthalene and n-dodecane, the strain first consumed naphthalene and then n-dodecane. Cultivation of the strain on n-dodecane was characterized by a long adaptation phase, in contrast to cultivation on naphthalene and a mixture of naphthalene and n-dodecane.

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11

Liang, Jun, and Fu Ping Wang. "Synthesis of Four Monodimensional Medium-Pore Zeolites and their Hydroisomerization Performances of n-Dodecane." Advanced Materials Research 236-238 (May 2011): 854–57. http://dx.doi.org/10.4028/www.scientific.net/amr.236-238.854.

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SAPO-11, SAPO-41, ZSM-22, ZSM-12 were synthesized by the hydrothermal method and characterized by XRD, SEM and NH3-TPD. Effects of pore channel, the number of acid sites and acid strength on hydroisomerization ofn-dodecane were examined over Pt-loaded corresponding zeolites. The results indicate that the selectivity to isomers in hydroisomerization ofn-dodecane is highly influenced by channel structure in zeolites and the conversion activity ofn-dodecane is dependent on acidity of zeolites. Monodimensional ten-ring molecular sieves are ideal catalytic materials for higher isomerization selectivity in hydroisomerization ofn-dodecane regardless of acid strength, such as SAPO-11, SAPO-41 and ZSM-22.

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12

Chang, Li-Yu, Ting-Wei Liao, Ming-Lin Ye, and Yi-Je Juang. "Utilization of n-dodecane as coupling layer for reusable acoustofluidic microchips." Journal of Micromechanics and Microengineering 31, no. 12 (2021): 127001. http://dx.doi.org/10.1088/1361-6439/ac2f51.

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Abstract In this study, n-dodecane used as the coupling layer for reusable acoustofluidic microchips was investigated. n-dodecane has the similar viscosity to that of water. However, it possesses much lower surface tension and higher boiling point compared to water. When dispensing a droplet of n-dodecane on lithium niobate (LiNO3) substrate with interdigital transducers and placing the polydimethylsiloxane microchannel on top of it, n-dodecane can easily wick through and completely occupy the interstitial space. Moreover, it can be readily removed from the substrate without leaving residue. The experimental results showed that the reusable acoustofluidic microchips can be operated at higher input voltages and longer duration when applying n-dodecane as the coupling layer. Attenuation of the acoustic radiant force was observed through decrease of the particle velocity, which is in agreement with the literature results. Decreasing the thickness of the coupling layer can alleviate the attenuation effect and a linear relationship between particle velocity and thickness on a semi-log plot was obtained.

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13

Gao, Shan-Bin, Zhen Zhao, Xue-Feng Lu, et al. "Hydrocracking diversity in n-dodecane isomerization on Pt/ZSM-22 and Pt/ZSM-23 catalysts and their catalytic performance for hydrodewaxing of lube base oil." Petroleum Science 17, no. 6 (2020): 1752–63. http://dx.doi.org/10.1007/s12182-020-00500-7.

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AbstractNobel metallic Pt/ZSM-22 and Pt/ZSM-23 catalysts were prepared for hydroisomerization of normal dodecane and hydrodewaxing of heavy waxy lube base oil. The hydroisomerization performance of n-dodecane indicated that the Pt/ZSM-23 catalyst preferred to crack the C–C bond near the middle of n-dodecane chain, while the Pt/ZSM-22 catalyst was favorable for breaking the carbon chain near the end of n-dodecane. As a result, more than 2% of light products (gas plus naphtha) and 3% more of heavy lube base oil with low-pour point and high viscosity index were produced on Pt/ZSM-22 than those on Pt/ZSM-23 while using the heavy waxy vacuum distillate oil as feedstock.

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Nakamura, Naotake, Kenjiro Uno, and Yoshihiro Ogawa. "Dodecane-1,12-dithiol." Acta Crystallographica Section E Structure Reports Online 57, no. 6 (2001): o508—o510. http://dx.doi.org/10.1107/s160053680100719x.

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15

Sagert, Norman H., and Danny W. P. Lau. "The distribution of branched octanols between dodecane and water." Canadian Journal of Chemistry 63, no. 4 (1985): 789–92. http://dx.doi.org/10.1139/v85-130.

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The distribution of four branched chain octanols, 3-ethyl-3-hexanol, 4-ethyl-3-hexanol, 2-ethyl-4-methylpentanol, and 4-octanol, has been measured between dodecane and water. Measurements were made at alcohol concentrations in the dodecane of less than 0.1 mol/dm3, and as a function of temperature from 10 °C to 35 °C. From these distribution data, standard thermodynamic functions for transfer were calculated. Standard Gibbs energies of transfer from water to dodecane at 25 °C were in the range −14.1 to −15.1 kJ/mol, whereas the standard enthalpies of transfer at 25 °C varied from 29 to 39 kJ/mol. Thus, the change in the standard enthalpy tends to inhibit transfer, but a large standard entropy of transfer results in dodecane being the favoured phase.

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Kao, Chen-Feng, and Wen-Churng Lin. "Liquid−Liquid Equilibria of the Ternary Systems Dodecane + Butylbenzene + Sulfolane, Dodecane + 1,4-Diisopropylbenzene + Sulfolane, and Dodecane + Octylbenzene + Sulfolane." Journal of Chemical & Engineering Data 44, no. 2 (1999): 338–42. http://dx.doi.org/10.1021/je980261c.

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Wei, Wei, Chang Jie, Sun Yu-Han, and Zhong Bing. "Cluster in Dehydrogenation of Dodecane to Internal Dodecane in Supercritical Phase." Acta Physico-Chimica Sinica 17, no. 01 (2001): 59–61. http://dx.doi.org/10.3866/pku.whxb20010112.

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18

Wilk, R. D., R. S. Cohen, and N. P. Cernansky. "Ignition studies of dodecane and binary mixtures of dodecane and tetralin." Symposium (International) on Combustion 20, no. 1 (1985): 187–93. http://dx.doi.org/10.1016/s0082-0784(85)80502-6.

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19

Yazdi, Mohammad Arab Pour, Jean Baptiste Sanchez, Eric Monsifrot, Pascal Briois, Franck Berger, and Alain Billard. "Dodecane Sensing with Double Substituted LaCoO₃ Nanowires Deposited by Reactive Magnetron Sputtering." Key Engineering Materials 543 (March 2013): 192–95. http://dx.doi.org/10.4028/www.scientific.net/kem.543.192.

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This paper reports results of dodecane-sensing studies with double-substituted LaCoO3perovskite oxide nanowires. La0.40Sr0.15Ag0.45CoO3-αnanowires were co-sputtered from metallic La, Sr, Ag and Co targets in the presence of a reactive argon-oxygen gas mixture. As deposited coatings are amorphous and crystallise in the perovskite structure after annealing at 873 K for 2 hours under air. Electrical response of the La0.40Sr0.15Ag0.45CoO3-αnanowires was measured at different temperature under air and under air containing 1 to 100 ppm (v) of dodecane vapour. The electrical signal of the nanowires was found to be high and it was possible to detect low concentrations of dodecane (under 5 ppm (v) ) at 573 K.

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20

Liu, Ruiqing, Ruiliang Zhang, Yizhuo Feng, and Tiantian Yang. "Establishment and Validation of a Two-Component Surrogate Fuel Chemical Kinetic Skeletal Model for Fischer–Tropsch Fuel Synthesized from Coal." Energies 13, no. 5 (2020): 1168. http://dx.doi.org/10.3390/en13051168.

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Fischer–Tropsch (F–T) fuel, synthesized from coal-to-liquid (CTL), is an alternative fuel with clean and efficient characteristics. In this study, a surrogate fuel model was developed, including n-dodecane (n-C12H26) and iso-octane (i-C8H18), which represents the n-alkane and iso-alkane in F–T fuel synthesized from CTL, respectively. The proportions of the components in the surrogate fuel are determined by the characteristics of the practical fuel, including cetane number (CN), C/H ration and component composition. For the establishment of the skeletal mechanism model, firstly, based on a two-step direct relationship graph (DRG) and the computational singular perturbation (CSP) importance index method, a reduced model of n-dodecane was developed involving 159 species and 399 reactions, while the detailed n-dodecane mechanism consists of 1279 species and 5056 reactions. Then, the n-dodecane skeletal mechanism was constructed based on a decoupling methodology, involving the skeletal C12 mechanism from the reduced mechanism, a C2-C3 sub mechanism and a detailed H2/CO/C1 sub mechanism. Finally, the skeletal mechanism for the F–T surrogate fuel was developed, including the n-dodecane skeletal mechanism and an iso-octane macromolecular skeletal mechanism. The final mechanism for the F–T diesel surrogate fuel consists of 169 species and 406 reactions. The n-dodecane skeletal mechanism and iso-octane skeletal mechanism were validated on various fundamental experiments, including the ignition delay in shock tubes, the primary species concentrations in jet-stirred reactors and the premixed laminar flame over wide operating conditions, which show great agreement between the predictions and measurements. Moreover, an F–T surrogate fuel mechanism was employed to simulate the combustion characteristics of an engine using computational fluid dynamics (CFD). The results show that the mechanism can predict the performance of F–T fuel combustion in engine accurately.

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Dehmlow, Eckehard Volker, Hans-Jörg Breyholz, Beate Neumann, Anja Stammler, and Hans-Georg Stammler. "New Tandem Ring Enlargements of Bicyclo[3.3.0]octanes to Bicyclo[5.5.0]dodecanes and Subsequent Conversions into Tricyclo[5.5.0.0.2,9]dodecane and Tricyclo[5.5.0.02,10]dodecane Derivatives." European Journal of Organic Chemistry 2001, no. 7 (2001): 1413–20. http://dx.doi.org/10.1002/1099-0690(200104)2001:7<1413::aid-ejoc1413>3.0.co;2-8.

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22

Lemmon, Eric W., and Marcia L. Huber. "Thermodynamic Properties ofn-Dodecane." Energy & Fuels 18, no. 4 (2004): 960–67. http://dx.doi.org/10.1021/ef0341062.

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Huber, Marcia L., Arno Laesecke, and Richard Perkins. "Transport Properties ofn-Dodecane." Energy & Fuels 18, no. 4 (2004): 968–75. http://dx.doi.org/10.1021/ef034109e.

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Zhou, Peizheng, and Billy L. Crynes. "Thermolytic reactions of dodecane." Industrial & Engineering Chemistry Process Design and Development 25, no. 2 (1986): 508–14. http://dx.doi.org/10.1021/i200033a027.

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Maia de Oliveira, Humberto N., Francisco W. Bezerra Lopes, Afonso A. Dantas Neto, and Osvaldo Chiavone-Filho. "Vapor−Liquid Equilibria for Pentane + Dodecane and Heptane + Dodecane at Low Pressures." Journal of Chemical & Engineering Data 47, no. 6 (2002): 1384–87. http://dx.doi.org/10.1021/je020037u.

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Tong, Zhongsheng, Fred Widmer, Tania C. Sorrell, et al. "In Vitro Activities of Miltefosine and Two Novel Antifungal Biscationic Salts against a Panel of 77 Dermatophytes." Antimicrobial Agents and Chemotherapy 51, no. 6 (2007): 2219–22. http://dx.doi.org/10.1128/aac.01382-06.

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ABSTRACT The susceptibilities of 77 dermatophytes to miltefosine (MI), 1,12-bis(4-pentylpyridinium)dodecane (PYR), 1,12-bis(tributylammonium)dodecane (AM), itraconazole (ITC), terbinafine (TRB), and butenafine (BTF) were compared. Geometric mean MICs of TRB, BTF, ITC, MI, PYR, and AM were 0.039, 0.059, 1.718, 0.671, 6.006, and 4.771 μg/ml, respectively. MI was more active than ITC (P < 0.001).

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Liu, Lingyun, Erle Qiao, Liang Shen, Fanfei Min, and Changguo Xue. "Effect of Hydration Layer on the Adsorption of Dodecane Collector on Low-Rank Coal: A Molecular Dynamics Simulation Study." Processes 8, no. 10 (2020): 1207. http://dx.doi.org/10.3390/pr8101207.

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The hydration layer has a significant effect on the adsorption behavior of reagents during the flotation process of low-rank coal. Understanding the effect of hydration layer on the adsorption of common collectors on low-rank coal is a prerequisite for proposing a new enhanced coal floatation method. In this study, a smooth low-rank coal surface model with a density of 1.2 g/cm3 was constructed and compared with the XPS results. Three different systems, coal-water, coal-collector, and coal-water-collector, were constructed. Molecular dynamics method was applied to study the adsorption behaviors of water and dodecane molecules. Simulation results revealed that a stable hydration layer with a thickness of about 5 Å was formed due to the strong attraction of coal surface. The negative value of interaction energy (IE) indicated that dodecane molecules could spontaneously adsorb on the coal surface. Dodecane molecules were successfully adsorbed on the coal surface when it was located inside the hydration layer. While the dodecane molecule was outside the hydration layer, it could not pass through the hydration layer on the surface of low-rank coal.

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Rodiansono, Rodiansono, Muhammad Iqbal Pratama, Maria Dewi Astuti, Abdullah Abdullah, Agung Nugroho, and Susi Susi. "Selective Hydrogenation of Dodecanoic Acid to Dodecane-1-ol Catalyzed by Supported Bimetallic Ni-Sn Alloy." Bulletin of Chemical Reaction Engineering & Catalysis 13, no. 2 (2018): 311. http://dx.doi.org/10.9767/bcrec.13.2.1790.311-319.

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Selective hydrogenation of dodecanoic acid over supported bimetallic Ni-Sn alloy catalysts into dodecane-1-ol is demonstrated. Bimetallic nickel-tin supported on titanium oxide (Ni-Sn(1.5)/TiO2) and gamma-alumina (Ni-Sn(1.5)/g-Al2O3); 1.5 = Ni/Sn molar ratio) were synthesized via hydrothermal method in a sealed-Teflon autoclave reactor at 150 oC for 24 h, then followed by reducing with hydrogen gas at 400 oC for 1.5 h. The synthesized catalysts were characterized by means of XRD, IC-AES, N2-adsorption (BET method), H2-chemisorption, and NH3-TPD. Bimetallic Ni-Sn(1.5)/TiO2 catalyst was found to be effective for hydrogenation of dodecanoic acid (>99 % conversion) to dodecane-1-ol (93% yield) at 160 oC, 30 bar H2, and 20 h and the highest dodecane-1-ol (97 % yield) was obtained at initial pressure of H2, 50 bar. An increase of reaction temperature slightly enhanced the degree of hydrodeoxygenation of dodecanoic acid to produce dodecane over both Ni-Sn(1.5)/TiO2 and Ni-Sn(1.5)/g-Al2O3 catalysts. Copyright © 2018 BCREC Group. All rights reservedReceived: 26th November 2017; Revised: 24nd December 2017; Accepted: 24th January 2018; Available online: 11st June 2018; Published regularly: 1st August 2018How to Cite: Rodiansono, R. Pratama, M.I., Astuti, M.D., Abdullah, A., Nugroho, A., Susi, S. (2018). Selective Hydrogenation of Dodecanoic Acid to Dodecane-1-ol Catalyzed by Supported Bimetallic Ni-Sn Alloy. Bulletin of Chemical Reaction Engineering & Catalysis, 13 (2): 311-319 (doi:10.9767/bcrec.13.2.1790.311-319)

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Jo, Seong, Dong Ju, Suk Jung, et al. "Performance of an Auto-Reduced Nickel Catalyst for Auto-Thermal Reforming of Dodecane." Catalysts 8, no. 9 (2018): 371. http://dx.doi.org/10.3390/catal8090371.

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To investigate the catalytic performance of diesel reforming catalysts for production of hydrogen gas, Ni-Al catalyst was prepared by the polymer-modified incipient method (NA10-PM). NA10-PM showed excellent catalytic performance and economic feasibility in the auto-thermal reforming reaction, compared to other commercially available catalysts. In particular, auto-reduced NA10-PM showed higher dodecane conversion and similar selectivity at 750 °C compared to H2-reduced NA10-PM. X-ray diffraction (XRD) studies showed that the fresh state of NA10-PM initially automatically reduced by product gases through thermal decomposition of dodecane, and then NiAl2O4 was completely reduced to metallic nickel by the CO and H2 gases produced during the reaction. Additionally, catalytic performance of auto-reduced NA10-PM were investigated at varying steam/carbon molar ratio (S/C) and oxygen/carbon molar ratio (O2/C) in order to determine the optimum conditions of the auto-thermal reforming reaction. The conversion of dodecane over auto-reduced NA10-PM catalyst was remarkable (93%) and increased during the reaction, under conditions of S/C = 1.23, O2/C = 0.25, and gas hourly space velocity of 12,000 h−1 at 750 °C. The results of this study demonstrated that the auto-reduced NA10-PM catalyst was applied successfully for auto-thermal reforming of dodecane.

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Feng, Hongzu, Changqing Gou, Dilinuer Aimaiti, Peng Sun, Lan Wang, and Haiting Hao. "Plant volatile organic compounds attractive to Lygus pratensis." Open Life Sciences 17, no. 1 (2022): 362–71. http://dx.doi.org/10.1515/biol-2022-0038.

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Abstract Lygus pratensis, an important agricultural pest, is seriously detrimental to cotton in China. For the research and development of attractants, the present study screened and identified plant volatiles with activity against the pest. Out of the total 20 volatiles identified from seven hosts, 16 volatiles were selected and evaluated. Electrophysiological test results revealed the highest electroantennogram values of heptacosane, heptadecane, decanal, (E)-4-hexen-1-ol, dodecane, β-pinene, and cis-3-hexenyl isovalerate on adult insects. A significant difference in the behavior of female adults (P < 0.01) was noted in the trend behavioral tests when the concentration of heptacosane, nonadecane, heptadecane, decanal, 3-hexen-1-ol, and dodecane was 10−3 (V/V), and that of β-pinene was 10−4 (V/V). The field trapping test confirmed a significant difference in the trapping effect of heptadecane at 10−2 (V/V) and 10−3 (V/V), decanal at 10−1 (V/V) and 10−3 (V/V), β-pinene at 10−2 (V/V), and dodecane at 10−4 (V/V) compared to that of other volatiles (P < 0.05). These findings suggested the strong attractant effect of heptadecane, dodecane, decanal, and β-pinene on adults, indicating their potential application as effective attractants for the ecological control of L. pratensis.

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Garkushin, I. K., A. V. Kolyado, and I. G. Yakovlev. "Phase diagrams of diphenyl–n-dodecane and diphenyl–diphenyl oxide–n-dodecane systems." Russian Journal of Physical Chemistry A 90, no. 8 (2016): 1574–77. http://dx.doi.org/10.1134/s0036024416080082.

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Wei, Yan-Ju, Ya-Jie Zhang, Xiao-Dong Zhu, et al. "Effects of Diesel Hydrocarbon Components on Cetane Number and Engine Combustion and Emission Characteristics." Applied Sciences 12, no. 7 (2022): 3549. http://dx.doi.org/10.3390/app12073549.

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Commercial diesel consists of hundreds of hydrocarbons such as alkanes, cycloalkanes, and aromatics. The components of the fuel’s composition are what determine its physical and ignition properties, and their variations affect engine performance. In this study, n-heptane, n-dodecane, tetralin, and decalin were chosen as typical additives to blend with commercial diesel according to the China VI standard (Heavy Duty Diesel Vehicle Pollutant Emission Limits and Measurement Methods) in 20% and 50% volume fractions, respectively. The physical properties of the fuel blends, such as viscosity, density, cetane number (CN), and distillation range, were measured first. Then, the commercial diesel’s lower heat value was measured, and blended fuels were calculated accordingly. The CN of the blended fuel is tested by an Ignition Quality Tester (IQT), which is known as the derived cetane number (DCN). The results show that adding n-dodecane increases the value of DCN, while tetralin reduces the DCN, and n-heptane and decalin have negative effects. This study uses a type of WP12 diesel engine made by Weichai that meets China’s emission regulation 6. During the tests, the fuel injection strategy was kept as a pure diesel operation without any modifications. Compared with pure diesel operation, the bench test results show the following characteristics: the maximum torque output increased with increased decalin, followed by tetralin and n-dodecane, while n-heptane has a side effect compared to pure diesel operation. The addition of n-dodecane and n-heptane can reduce fuel consumption, while tetralin will increase it, and decalin has no obvious effect on fuel consumption. It was found that n-heptane increases HC and NOx emissions significantly. Furthermore, n-dodecane slightly increases CO, HC and NOx emissions. Decalin increases CO and HC emissions when mixed in a large proportion. In addition, tetralin causes a substantial increase in HC, CO and NOx emissions at medium and high loads.

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Babu, RJ, A. Chatterjee, E. Ahaghotu, and M. Singh. "Percutaneous absorption and skin irritation upon low-level prolonged dermal exposure to nonane, dodecane and tetradecane in hairless rats." Toxicology and Industrial Health 20, no. 6-10 (2004): 109–18. http://dx.doi.org/10.1191/0748233704th197oa.

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Even though the dermal toxicity of hydrocarbon fuels has been well established in the literature, there is little information available on the dermal penetration kinetics and irritation potential of the individual hydrocarbons. The penetration and skin retention of nonane, dodecane and tetradecane was assessed in vitro using hairless rats’ skin. The effects of unocclusive dermal exposures of these chemicals (15 mL every 2 h for 8 h a day for four days) on the transepidermal water loss (TEWL) and erythema were measured in CD hairless rats. The expression of interleukin 1a (IL-1a) and TNF-a in the skin and blood were measured at the end of dermal exposures. The flux of dodecane was 3- and 77-fold higher than nonane and tetradecane. The retention of chemicals in stratum corneum (SC) was in the order of tetradecane-dodecane-nonane, and directly correlated to the log Kp (r2-0.9900) and molecular weight of the chemicals (r2-0.8782). The TEWL and erythema data indicate that irritation was in the following order: tetradecane-dodecane-nonane. Likewise, the expression of IL-1a in the blood and TNF-a in the skin after dermal exposures was higher for tetradecane followed by dodecane and nonane compared to control. In conclusion, the aliphatic hydrocarbon chemicals of the present study induced cumulative irritation upon low-level repeat exposures for a four-day period. The affinity of the chemicals to SC and their gradual accumulation in the skin in the present study is the probable cause for the differences in the skin irritation profiles of different aliphatic chemicals. The findings of the present study will be helpful in understanding the skin irritation response of the chemicals in humans; indeed the reality check arises from dermal exposures in humans and human experience in occupational handling of these chemicals.

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Zhang, He, Wenli Liu, Hongxiang Xu, Qiming Zhuo, and Xiaopeng Sun. "Adsorption Behavior of Methyl Laurate and Dodecane on the Sub-Bituminous Coal Surface: Molecular Dynamics Simulation and Experimental Study." Minerals 9, no. 1 (2019): 30. http://dx.doi.org/10.3390/min9010030.

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Biodiesel was found to be a more effective collector on low-rank coal flotation than the common oily collectors (diesel and kerosene) in previous research. However, the micro-adsorption behavior of these collectors on the coal surface remains to be further explored. In the present work, the adsorption behavior of methyl laurate and dodecane, representing biodiesel and common oily collectors, was investigated using experimental and molecular dynamics (MD) simulation methods. The results of MD simulations showed that dodecane was difficult to diffuse on the surface of sub-bituminous coal and formed a spherical structure on the surface of sub-bituminous coal. Methyl laurate was adsorbed on the surface of coal via the head group (ester group), while the tail group (alkyl chain) was exposed to a liquid environment, forming a wider network structure on the coal surface. The above results, mainly attributed to methyl laurate, had a higher interaction with the sub-bituminous surface compared to dodecane. The self-diffusion coefficient results showed that the aggregate configurations of methyl laurate cause higher water mobility, which was more conducive to enhancing the hydrophobicity of the coal surface. The adhesion efficiency measurement and X-ray photoelectron spectrometer (XPS) analysis confirmed that methyl laurate could cover more oxygen-containing functional groups on the coal surface than dodecane, thus enhancing the hydrophobicity of coal. The results of simulations conformed to the experimental results.

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35

Lusiani, Niccolò, Ewa Pavlova, Richard Hoogenboom, and Ondřej Sedláček. "Cationic Ring-Opening Polymerization-Induced Self-Assembly(CROPISA) of 2-Oxazolines: From Block Copolymers to One-StepGradient Copolymer Nanoparticles." Angewandte Chemie International Edition 64 (November 29, 2024): e202416106. https://doi.org/10.5281/zenodo.15039742.

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In recent years, polymerization-induced self-assembly (PISA) has emerged as a powerful method for thestraightforward synthesis of polymer nanoparticles at high concentration. In this study, we describe for the first time thesynthesis of poly(2-oxazoline) nanoparticles by dispersion cationic ring-opening polymerization-induced self-assembly(CROPISA) in n-dodecane. Specifically, a n-dodecane-soluble aliphatic poly(2-(3-ethylheptyl)-2-oxazoline) (PEHOx)block was chain-extended with poly(2-phenyl-2-oxazoline) (PPhOx). While the PhOx monomer is soluble in n-dodecane,its polymerization leads to n-dodecane-insoluble PPhOx, which leads to in situ self-assembly of the formed PEHOx-b-PPhOx copolymers. The polymerization kinetics and micellization upon second block formation were studied, anddiverse nanoparticle dispersions were prepared, featuring varying block lengths and polymer concentrations, leading todispersions with distinctive morphologies and physical properties. Finally, we developed a single-step protocol for thesynthesis of polymer nanoparticles directly from monomers via gradient copolymerization CROPISA, which exploits thesignificantly greater reactivity of EHOx compared to that of PhOx during the statistical copolymerization of bothmonomers. Notably, this approach provides access to formulations with monomer compositions otherwise unattainablethrough the block copolymerization method. Given the synthetic versatility and application potential of poly(2-oxazolines), the developed CROPISA method can pave the way for advanced nanomaterials with favorable propertiesas demonstrated by using the obtained nanoparticles for stabilization of Pickering emulsions.

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Weiguo, Shen, and Arthur G. Williamson. "Volumes of mixing of ternary alkane mixtures with branched chain components." Canadian Journal of Chemistry 70, no. 7 (1992): 2003–8. http://dx.doi.org/10.1139/v92-251.

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Measurements at 25 °C are reported for the volumes of mixing of binary mixtures of n-dodecane + 2 methyl pentane and of ternary mixtures created by mixing an equimolar mixture of (n-decane + n-tetradecane) with each of the isomers of hexane. The results are compared with the work of Hamam etal. for binary mixtures of n-dodecane with the hexane isomers and shown to be in accord with the principle of congruence within the limits of experimental accuracy of the measurements.

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37

An, Maoyan, Yinfei Liao, Yijun Cao, Xiaodong Hao, and Longfei Ma. "Improving Low Rank Coal Flotation Using a Mixture of Oleic Acid and Dodecane as Collector: A New Perspective on Synergetic Effect." Processes 9, no. 3 (2021): 404. http://dx.doi.org/10.3390/pr9030404.

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The mixed collector can improve low rank coal flotation efficiency, but its synergistic mechanism needs to be further explored. In this paper, oleic acid-dodecane (OA-D), oleic acid (OA), and dodecane (D) were employed to treat the low rank coal for revealing new synergistic mechanism of the mixed collector. First the surface free energy of the coal, the surface free energy of coal-water and coal-water-coal were calculated. Then wetting heat measurement, X-ray Photoelectron Spectroscopy (XPS) and FTIR were used to analyze synergistic mechanism of the mixed collector in depth. The results showed that OA-D obtained a higher combustible recovery than using OA and D, respectively. The essence of synergetic mechanism of OA-D was that they formed a relatively ordered “supramolecular structure” on the low rank coal surface, especially there were hydrophobic and van der Waals forces between the oleic acid chain and the dodecane chain that can promote the formation of a continuous collector film.

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38

Ansorena, D., I. Astiasarán, and J. Bello. "Changes in volatile compounds during ripening of chorizo de Pamplona elaborated with Lactobacillus plantarum and Staphylococcus carnosus Cambios en los compuestos volátiles durante la maduración del chorizo de Pamplona elaborado con Lactobacillus plantarum y Staphylococcus carnosus." Food Science and Technology International 6, no. 6 (2000): 439–47. http://dx.doi.org/10.1177/108201320000600602.

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The ripening of chorizo de Pamplona was followed through the changes of the volatile compounds extracted by a simultaneous destilation-extraction with dichloromethane. An increase of the number and concentration of compounds was detected during the maturation, ranging from 63 compounds (10.26 mg dodecane/g dry matter) to 98 substances (223.16 mg of dodecane/g dry matter) identified in the mixing and in the final product, respectively. Acids showed the highest increase during the ripening, reaching 90% of the total amount of compounds at the end of the process, followed by esters and aldehydes. Short chain fatty acids, which contributed to the typical organoleptic charac teristics of dry fermented sausages, became apparent from the 21st day and accounted for only 1.3 mg of the total of acids in final product (202 mg dodecane/g dry matter). Sulphur compounds decreased slightly during the ripening, a result of the decrease in the content of the disulphide di- 2-propenyl, a compound originated from garlic.

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39

Yamaguchi, Ryohei, Keiji Honda, and Mituyosi Kawanisi. "3,12-Cycloiceane (pentacyclo[6.3.1.02,4.05,10.07,8]dodecane)." Journal of the Chemical Society, Chemical Communications, no. 2 (1987): 83. http://dx.doi.org/10.1039/c39870000083.

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SIMÕES-MOREIRA, J. R., and J. E. SHEPHERD. "Evaporation waves in superheated dodecane." Journal of Fluid Mechanics 382 (March 10, 1999): 63–86. http://dx.doi.org/10.1017/s0022112098003796.

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We have observed propagating adiabatic evaporation waves in superheated liquid dodecane, C12H26. Experiments were performed with a rapid decompression apparatus at initial temperatures of 180–300°C. Saturated dodecane in a tube was suddenly depressurized by rupturing a diaphragm. Motion pictures and still photographic images, and pressure and temperature data were obtained during the evaporation event that followed depressurization. Usually, a front or wave of evaporation started at the liquid free surface and propagated into the undisturbed regions of the metastable liquid. The evaporation wave front moved with a steady mean velocity but the front itself was unstable and fluctuating in character. At low superheats, no waves were observed until a threshold superheat was exceeded. At moderate superheats, subsonic downstream states were observed. At higher superheats, the downstream flow was choked, corresponding to a Chapman–Jouguet condition. At the most extreme superheat tested, a vapour content of over 90% was estimated from the measured data, indicating a nearly complete evaporation wave. Our results are interpreted by modelling the evaporation wave as a discontinuity, or jump, between a superheated liquid state and a two-phase liquid–vapour downstream state. Reasonable agreement is found between the model and observations; however, there is a fundamental indeterminacy that prevents the prediction of the observed wave speeds.

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41

Hoffmann, H. M. R., Angela Walenta, Ulrike Eggert, and Dietmar Schomburg. "Trispiro[2.1.2.1.2.1]dodecane-4,8,12-trione." Angewandte Chemie International Edition in English 24, no. 7 (1985): 607–8. http://dx.doi.org/10.1002/anie.198506071.

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42

Wang, Ya, Xiaochao Xian, Xu Hou, Xiangwen Zhang, Li Wang, and Guozhu Liu. "Catalytic cracking of binary hydrocarbons of n-dodecane and iso-dodecane under supercritical conditions." Journal of Analytical and Applied Pyrolysis 113 (May 2015): 133–36. http://dx.doi.org/10.1016/j.jaap.2014.11.015.

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43

Shafei, Emad N., Ahmad Masudi, Zain H. Yamani, and Oki Muraza. "Acidity modifications of nanozeolite-Y for enhanced selectivity to olefins from the steam catalytic cracking of dodecane." RSC Advances 12, no. 28 (2022): 18274–81. http://dx.doi.org/10.1039/d2ra02184f.

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Gonnelli, Adriano, Silvia Pieraccini, Enrico J. Baldassarri, et al. "Metallo-responsive self-assembly of lipophilic guanines in hydrocarbon solvents: a systematic SAXS structural characterization." Nanoscale 12, no. 2 (2020): 1022–31. http://dx.doi.org/10.1039/c9nr08556d.

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45

Mannoor, Madhusoodanan, Sangmo Kang, and Yong Kweon Suh. "Molecular Dynamics Simulation of Aggregates in the Dodecane/span80 System and Their Behaviour in an Electric Field." Advances in Condensed Matter Physics 2015 (2015): 1–9. http://dx.doi.org/10.1155/2015/739458.

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Molecular dynamics simulation of self-assembly of surfactant span80 molecules to form reverse micelles in nonpolar liquid dodecane is carried out. Simulations are performed using a united atom model for dodecane and a hybrid model for span80 molecules. Various physical characteristics of reverse micelle are measured, and the same are compared with available experimental results. Presence of charge carriers in the form of solvated ions in the core of reverse micelles is confirmed by the simulation. Movement of reverse micelles under the effect of uniform external electric field is also discussed.

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Burýšková, B., L. Bláha, D. Vršková, K. Šimková, and B. Maršálek. "Sublethal Toxic Effects and Induction of gGutathione S-transferase by Short-Chain Chlorinated Paraffins (SCCPs) and C-12 alkane (dodecane) in Xenopus laevis Frog Embryos." Acta Veterinaria Brno 75, no. 1 (2006): 115–22. http://dx.doi.org/10.2754/avb200675010115.

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Short chain chlorinated paraffins (SCCPs) are important industrial chemicals with high persistence in the environment but poorly characterized ecotoxicological effects. We studied embryotoxic effects of commercial mixture of SCCP (carbon length C-12, 56% of chlorine; CP56-12) and non-chlorinated n-alkane (dodecane, C-12) in the 96h Frog Embryo Teratogenesis Assay - Xenopus (FETAX). Only weak lethal effects were observed for both substances (the highest tested concentration 500 mg/L of both chemicals caused up to 11% mortality). On the other hand, we observed developmental malformations and reduced embryo growth at 5 mg/l and higher concentrations. However, the effects were not related to chlorination pattern as both SCCPs and dodecane induced qualitatively similar effects. SCCPs also significantly induced phase II detoxification enzyme glutathione S-transferase (GST) in Xenopus laevis embryos even at 0.5 mg/L, and this biomarker might be used as another early warning of chronic toxic effects. Our results newly indicate significant developmental toxicity of both SCCPs and n-dodecane to aquatic organisms along with inductions of specific biochemical toxicity mechanisms.

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Ngo, Thanh Hai, and Adrian Schumpe. "Oxygen Absorption into Stirred Emulsions of n-Alkanes." International Journal of Chemical Engineering 2012 (2012): 1–7. http://dx.doi.org/10.1155/2012/265603.

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Absorption of pure oxygen into aqueous emulsions of n-heptane, n-dodecane, and n-hexadecane, respectively, has been studied at 0 to 100% oil volume fraction in a stirred tank at the stirring speed of 1000 min−1. The volumetric mass transfer coefficient, , was evaluated from the pressure decrease under isochoric and isothermal (298.2 K) conditions. The O/W emulsions of both n-dodecane and n-hexadecane show a maximum at 1-2% oil fraction as reported in several previous studies. Much stronger effects never reported before were observed at high oil fractions. Particularly, all n-heptane emulsions showed higher mass-transfer coefficients than both of the pure phases. The increase is by upto a factor of 38 as compared to pure water at 50% n-heptane. The effect is tentatively interpreted by oil spreading on the bubble surface enabled by a high spreading coefficient. In W/O emulsions of n-heptane and n-dodecane increases with the dispersed water volume fraction; the reason for this surprising trend is not clear.

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SAMANTA, SUMAN K., ASISH PAL, and SANTANU BHATTACHARYA. "AN INSIGHT INTO FIBER–SOLVENT MEDIATED MODULATION OF NANO-FIBRILLAR ORGANOGELS." International Journal of Nanoscience 10, no. 04n05 (2011): 547–54. http://dx.doi.org/10.1142/s0219581x11009374.

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The effect of gelation and the modulation of their properties with the variation of aliphatic hydrocarbon solvents, e.g., n-decane and n-dodecane have been presented for a homologous series of amides of L-alanine with fatty acids. The gelation properties of these compounds were studied by a number of physical methods including scanning electron microscopy, X-ray diffraction, differential scanning calorimetry, rheology etc. It was found that the gelation properties vary with the chain length of the host aliphatic hydrocarbons. Scanning electron microscopic images showed modulation of the fiber diameters upon changing the solvent from n-decane to n-dodecane and this has been confirmed by the results obtained from small angle X-ray scattering studies independently. Thermal properties were observed under the differential scanning calorimetric studies which showed an increase in the sol–gel transition temperatures upon increase in the chain length of the hydrocarbon solvent. The mechanical behavior of such assemblies has been observed under rheological experiments which showed a more viscoelastic response for the gels in n-decane compared to n-dodecane.

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Bessa, Larissa Castello Branco Almeida, María Dolores Robustillo, Bianca Cristine Marques, Carmen Cecilia Tadini, and Filho Pedro de Alcântara Pessôa. "Experimental determination and thermodynamic modeling of solid-liquid equilibrium of binary systems containing representative compounds of biodiesel and fossil fuels: Ethyl esters and n-dodecane." Fuel 237 (June 5, 2019): 1132–40. https://doi.org/10.1016/j.fuel.2018.10.080.

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Despite recent advances on biodiesel production, its behavior at low temperatures does not favor its use in aviation engines. A better understanding of the solid-liquid phase behavior of systems comprising fatty esters and components of conventional jet fuel is therefore necessary to investigate the possibility of this use of biodiesel. To extend the knowledge on these systems, this work evaluated the solid–liquid equilibrium of binary mixtures containing ethyl esters and a jet fuel constituent (n-dodecane) through differential scanning calorimetry. Experimental results confirmed the occurrence of polymorphism for all pure components in solid phase. A simple eutectic behavior was observed for the binary systems containing n-dodecane and either ethyl myristate or ethyl oleate. However, the pairs composed by the n-dodecane and ethyl stearate, ethyl palmitate or ethyl laurate presented different phase transitions and regions of partial miscibility. The thermodynamic modeling of this equilibrium was carried out using different liquid-phase activity coefficient models, viz. Flory-Huggins, UNIFAC-Dortmund and the ideal solution model.

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Hung, Huang-Chin, and Gina S. Shreve. "Effect of Solute on Interfacial Properties and Micelle Structure of Dodecylbenzenesulfonate (DBS): Experimental and Molecular Dynamics Studies." International Journal of Molecular Sciences 25, no. 1 (2024): 678. http://dx.doi.org/10.3390/ijms25010678.

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A combined experimental and molecular dynamic simulation approach was used to examine the structure and interfacial properties of solute-saturated micelles. The properties of dodecylbenzenesulfonate (DBS) micelles were examined in dodecane and benzene hydrocarbon systems. Pyrene fluorescence was used to determine the aggregation number of surfactant monomers in the micelle systems. Molecular dynamic (MD) simulations using energy minimization applying the CHARMm force field with the TIP3P model for water. Comparison of the DBS/benzene and DBS/Dodecane micelles equilibrium structures via radial distribution function (RDF) and probability distribution function (PDF) analysis indicates that the area per head group for the DBS/Benzene micelle interface is significantly larger than that of the DBS/Dodecane at the interface. It was also determined that benzene molecules can move freely within the micelle while dodecane is strictly confined in the core of the micelle. The increased interfacial area per monomer caused by the insertion of benzene also reduces the effectiveness of the surfactant, which has implications for use in various environmental applications. However, the DBS/benzene micelle can solubilize many more hydrocarbon molecules in one micelle with less surfactant monomer (i.e., lower aggregation number) per micelle due to the increased available packing positions within the micelle. This, in turn, increases the efficiency of the surfactant in real-world applications which is consistent with previous laboratory results. Understanding the differing solubilization characteristics of surfactants against various classes of hydrocarbons in single solute systems is a necessary step to beginning to understand their solubilization properties in the mixed waste systems prevalent in most surfactant enhanced remediation (SEAR) strategies.

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Journal articles on the topic 'Dodecane'

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