Vibrational relaxation of small molecules in the liquid phase: Liquid nitrogen doped with CO2, CD4, or N2O

1978 ◽  
Vol 69 (4) ◽  
pp. 1418-1424 ◽  
Author(s):  
Carlos Manzanares I. ◽  
George E. Ewing
Keyword(s):  
Liquid Phase ◽  
Small Molecules ◽  
Liquid Nitrogen ◽  
Vibrational Relaxation ◽  
Nitrogen Doped ◽  
Phase Liquid

scholarly journals Thermodynamics and Machine Learning Based Approaches for Vapor–Liquid–Liquid Phase Equilibria in n-Octane/Water, as a Naphtha–Water Surrogate in Water Blends

Processes ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 413
Author(s):  
Sandra Lopez-Zamora ◽  
Jeonghoon Kong ◽  
Salvador Escobedo ◽  
Hugo de Lasa
Keyword(s):  
Machine Learning ◽  
Liquid Phase ◽  
Phase Equilibria ◽  
Aspen Plus ◽  
Phase Region ◽  
Two Phase ◽  
Technical Literature ◽  
Phase Liquid ◽  
Liquid Vapor ◽  
Vapor Liquid

The prediction of phase equilibria for hydrocarbon/water blends in separators, is a subject of considerable importance for chemical processes. Despite its relevance, there are still pending questions. Among them, is the prediction of the correct number of phases. While a stability analysis using the Gibbs Free Energy of mixing and the NRTL model, provide a good understanding with calculation issues, when using HYSYS V9 and Aspen Plus V9 software, this shows that significant phase equilibrium uncertainties still exist. To clarify these matters, n-octane and water blends, are good surrogates of naphtha/water mixtures. Runs were developed in a CREC vapor–liquid (VL_ Cell operated with octane–water mixtures under dynamic conditions and used to establish the two-phase (liquid–vapor) and three phase (liquid–liquid–vapor) domains. Results obtained demonstrate that the two phase region (full solubility in the liquid phase) of n-octane in water at 100 °C is in the 10-4 mol fraction range, and it is larger than the 10-5 mol fraction predicted by Aspen Plus and the 10-7 mol fraction reported in the technical literature. Furthermore, and to provide an effective and accurate method for predicting the number of phases, a machine learning (ML) technique was implemented and successfully demonstrated, in the present study.

Crystallization of Amorphous 55wt%Cr-45wt%Ni Films Induced by 60 ns (0.694 μm) Single Laser Pulse

1986 ◽  
Vol 74 ◽  
Author(s):  
I. Ursu ◽  
M. I. Bîrjega ◽  
C. A. Constantin ◽  
M. Dinescu ◽  
I. N. Mihailescu ◽  
...  
Keyword(s):  
Liquid Phase ◽  
Laser Pulse ◽  
Ruby Laser ◽  
Amorphous Matrix ◽  
Normal Incidence ◽  
Single Laser Pulse ◽  
Thermal Gradients ◽  
Single Laser ◽  
Threshold Conditions ◽  
Phase Liquid

AbstractAmorphous 55wt%Cr-45wt%Ni films (60 nm thick) supported on EM copper grids were irradiated in air at normal incidence with a ruby laser (λ∼, 0.694 μm) through a ≈ 1.5 mm diameter diaphragm using one single laser pulse of 60 ns (FWHM) with fluences ranging from 120 to 540 J.m−2. The structure of the irradiated films is studied by TEM and TED. As a rule due to the appearance of thermal gradients between the centre and the mesh edge of the EM grid, the crystallization took place under various conditions of reaction from liquid phase, liquid melted layers , activated diffusion in solid state, to under threshold conditions for the development of the crystalline nuclei in the amorphous matrix. Periodic resonant and unreso-nant structures also developed in the liquid melted layers.

scholarly journals Catalytic Performance of Nitrogen-Doped Activated Carbon Supported Pd Catalyst for Hydrodechlorination of 2,4-Dichlorophenol or Chloropentafluoroethane

Molecules ◽  
2019 ◽  
Vol 24 (4) ◽  
pp. 674 ◽  
Author(s):  
Haodong Tang ◽  
Bin Xu ◽  
Meng Xiang ◽  
Xinxin Chen ◽  
Yao Wang ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Liquid Phase ◽  
Gas Phase ◽  
Nitrogen Doping ◽  
Catalyst Surface ◽  
Catalytic Performance ◽  
Atomic Ratio ◽  
Pd Catalyst ◽  
Nitrogen Doped ◽  
The Stability

Nitrogen-doped activated carbon (N-AC) obtained through the thermal treatment of a mixture of HNO3-pretreated activated carbon (AC) and urea under N2 atmosphere at 600 °C was used as the carrier of Pd catalyst for both liquid-phase hydrodechlorination of 2,4-dichlorophenol (2,4-DCP) and gas-phase hydrodechlorination of chloropentafluoroethane (R-115). The effects of nitrogen doping on the dispersion and stability of Pd, atomic ratio of Pd/Pd2+ on the surface of the catalyzer, the catalyst’s hydrodechlorination activity, as well as the stability of N species in two different reaction systems were investigated. Our results suggest that, despite no improvement in the dispersion of Pd, nitrogen doping may significantly raise the atomic ratio of Pd/Pd2+ on the catalyst surface, with a value of 1.2 on Pd/AC but 2.2 on Pd/N-AC. Three types of N species, namely graphitic, pyridinic, and pyrrolic nitrogen, were observed on the surface of Pd/N-AC, and graphitic nitrogen was stable in both liquid-phase hydrodechlorination of 2,4-DCP and gas-phase hydrodechlorination of R-115, with pyridinic and pyrrolic nitrogen being unstable during gas-phase hydrodechlorination of R-115. As a result, the average size of Pd nanocrystals on Pd/N-AC was almost kept unchanged after liquid-phase hydrodechlorination of 2,4-DCP, whereas crystal growth of Pd was clearly observed on Pd/N-AC after gas-phase hydrodechlorination of R-115. The activity test revealed that Pd/N-AC exhibited a much better performance than Pd/AC in liquid-phase hydrodechlorination of 2,4-DCP, probably due to the enhanced stability of Pd exposed to the environment resulting from nitrogen doping as suggested by the higher atomic ratio of Pd/Pd2+ on the catalyst surface. In the gas-phase hydrodechlorination of R-115, however, a more rapid deactivation phenomenon occurred on Pd/N-AC than on Pd/AC despite a higher activity initially observed on Pd/N-AC, hinting that the stability of pyridinic and pyrrolic nitrogen plays an important role in the determination of catalytic performance of Pd/N-AC.

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