Carbon dioxide and propane nucleation: the emergence of a nucleation barrier

Data for the deposition of argon, nitrogen and carbon dioxide on cold, metal surfaces are considered in detail. It is concluded that argon and nitrogen deposit when the incident gas pressure equals the sublimation pressure at the respective surface temperature, and growth therefore proceeds without any significant intermediate nucleation barrier. Carbon dioxide, however, requires considerable supersaturation of the gaseous phase and consequently bulk deposition is inhibited by a nucleation barrier. The results are analysed with a view to determining the critical nucleus size and the adsorption energy. The ‘classical’ method of analysis gives unsatisfactory and inconclusive results. In contrast, the ‘atomistic’ approach is found to give a good account of the critical deposition phenomenon. The onset of gross deposition is found to be due entirely to capture of single molecules by stable nuclei, rather than by the formation of critical nuclei as the ‘ classical ’ theory wrongly assumes. The number of molecules in the critical nucleus is found to be about nine and a value of 9.4 kJ mol -1 is obtained for the adsorption energy, suggesting that nucleation occurs on top of a strongly bound adsorbed layer of contaminants or carbon dioxide itself, rather than on bare metal.

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Molecular level investigation of methane and carbon dioxide adsorption on SiO2 surface

Computational Materials Science ◽

10.1016/j.commatsci.2019.05.044 ◽

2019 ◽

Vol 168 ◽

pp. 213-220 ◽

Cited By ~ 4

Author(s):

Jianfei Zhao ◽

Zhouhua Wang ◽

Ping Guo ◽

Qiang Luo

Keyword(s):

Carbon Dioxide ◽

Molecular Level ◽

Carbon Dioxide Adsorption ◽

Sio2 Surface

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“Combustion always produces carbon dioxide and water”: a discussion of university chemistry students' use of rules in place of principles

Chemistry Education Research and Practice ◽

10.1039/c4rp00089g ◽

2014 ◽

Vol 15 (4) ◽

pp. 763-776

Author(s):

Amy D. Robertson ◽

Peter S. Shaffer

Keyword(s):

Carbon Dioxide ◽

Chemical Reactions ◽

Molecular Level ◽

Explanatory Models ◽

Introductory Chemistry ◽

Chemistry Students ◽

Conservation Principles ◽

Written Questions

On the basis of responses to written questions administered to more than one thousand introductory chemistry students, we claim that students often rotely apply memorized combustion rules instead of reasoning based on explanatory models for what happens at the molecular level during chemical reactions. In particular, many students argue that combustion produces carbon dioxide and/or water, even when the reactants do not contain hydrogen or carbon, an answer that is inconsistent with the principle of atom conservation. Our study also corroborates the finding that students frequently say that oxygen is “necessary for” or “used in” combustion reactions without connecting this reasoning to conservation principles, suggesting that this likewise may be a rotely applied, memorized rule.

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Proton Transfer Step in the Carbon Dioxide Capture by Monoethanol Amine: A Theoretical Study at the Molecular Level

The Journal of Physical Chemistry B ◽

10.1021/jp212225r ◽

2012 ◽

Vol 116 (7) ◽

pp. 2244-2248 ◽

Cited By ~ 27

Author(s):

Kenji Iida ◽

Hirofumi Sato

Keyword(s):

Carbon Dioxide ◽

Proton Transfer ◽

Theoretical Study ◽

Molecular Level ◽

Carbon Dioxide Capture ◽

Monoethanol Amine ◽

Transfer Step

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DFT studies for the evaluation of amine functionalized polystyrene adsorbents for selective adsorption of carbon dioxide

RSC Advances ◽

10.1039/c4ra00444b ◽

2014 ◽

Vol 4 (39) ◽

pp. 20323-20333 ◽

Cited By ~ 12

Author(s):

Rupa Shantamal Madyal ◽

Jyotsna Sudhir Arora

Keyword(s):

Carbon Dioxide ◽

Molecular Level ◽

Selective Adsorption ◽

Dft Studies ◽

Amine Functionalized

The current study provides molecular-level insights into the CO2–amine functionalized polystyrene complexes, enabling design of newer CO2 selective adsorbents.

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Electron Cytochemical Study of Carbon Dioxide Laser Effect on Rhesus Monkey Cornea

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010005113x ◽

1974 ◽

Vol 32 ◽

pp. 224-225

Author(s):

K. C. Tsou ◽

J. Morris ◽

P. Shawaluk ◽

B. Stuck ◽

E. Beatrice

Keyword(s):

Carbon Dioxide ◽

Electron Microscope ◽

Rhesus Monkey ◽

Carbon Dioxide Laser ◽

Cytochemical Study ◽

Laser Effect

While much is known regarding the effect of lasers on the retina, little study has been done on the effect of lasers on cornea, because of the limitation of the size of the material. Using a combination of electron microscope and several newly developed cytochemical methods, the effect of laser can now be studied on eye for the purpose of correlating functional and morphological damage. The present paper illustrates such study with CO2 laser on Rhesus monkey.

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