The conformation and reorientation of enclathrated 1,2-dichloroethane

1979 ◽  
Vol 57 (6) ◽  
pp. 635-637 ◽  
Author(s):  
S. K. Garg ◽  
D. W. Davidson ◽  
S. R. Gough ◽  
J. A. Ripmeester
Keyword(s):  
Activation Energy ◽  
Low Temperature ◽  
Dihedral Angle ◽  
Line Shape ◽  
Guest Molecule ◽  
Spectral Simulation ◽  
Rigid Lattice ◽  
Average Activation Energy ◽  
Dielectric Absorption

The rigid-lattice nmr line shape of the four-proton system in 1,2-dihaloethanes has been obtained by spectral simulation as a function of dihedral angle [Formula: see text] and used to show that 1,2-dichloroethane is encaged in the structure II hydrate in a gauche configuration with [Formula: see text] Very broad low-temperature dielectric absorption is associated with an average activation energy of 0.87 kcal/mol for guest-molecule reorientation.

Dielectric evidence for the formation of a clathrate hydrate by sulfuryl chloride

1983 ◽  
Vol 61 (9) ◽  
pp. 2053-2054 ◽  
Author(s):  
S. R. Gough ◽  
J. A. Ripmeester ◽  
D. W. Davidson
Keyword(s):  
Activation Energy ◽  
Low Temperature ◽  
Clathrate Hydrate ◽  
Sulfuryl Chloride ◽  
Dielectric Absorption ◽  
Structure Ii Clathrate Hydrate

A hydrate formed by SO2Cl2 at −20 °C is shown by its low temperature dielectric absorption to be a structure II clathrate hydrate. The activation energy for reorientation of encaged SO2Cl2 molecules is 1.1 kcal mol−1 between 19 and 41 K.

Study on Mechanism of Low Temperature Co-Pyrolysis of Duckweed and Flame Coal

2013 ◽  
Vol 724-725 ◽  
pp. 300-305
Author(s):  
Xuan Ming He ◽  
Jia Qi Fang ◽  
Ye Pan ◽  
Wei Li ◽  
Xiao Juan Wang
Keyword(s):  
Activation Energy ◽  
Low Temperature ◽  
Synergistic Effect ◽  
Kinetic Analysis ◽  
Kinetic Parameters ◽  
Pyrolysis Temperature ◽  
Light Component ◽  
Average Activation Energy ◽  
First Order ◽  
Pyrolysis Characteristics

Co-pyrolysis characteristics of long flame coal mixed with duckweed in different proportions were studied by using TG. And the kinetic parameters was also figured out by using the method of Coats-Redfern. It was exhibited significant synergistic effect created more the light component between duckweed and coal during co-pyrolysis, The pyrolysis rate of flame coal is much smaller than biomass, and the starting pyrolysis temperature of flame coal is higher than biomass. The kinetic analysis indicated that the pyrolytic processes can be described as first order reactions model. The average activation energy of duckweed and coal was 39.14kJ/mol and 46.43kJ/mol , and with the increasing of the duckweed proportion, pyrolysis activation energy was decreased.

Pt-Pd Nanoalloy for the Unprecedented Activation of Carbon-Fluorine Bond at Low Temperature

2019 ◽  
Author(s):  
Raghu Nath Dhital ◽  
keigo nomura ◽  
Yoshinori Sato ◽  
Setsiri Haesuwannakij ◽  
Masahiro Ehara ◽  
...  
Keyword(s):  
Activation Energy ◽  
Low Temperature ◽  
Dft Calculations ◽  
Bond Activation ◽  
Mild Conditions ◽  
Selective Transformation ◽  
Rate Determining Step ◽  
Highly Active ◽  
Harsh Conditions ◽  
Reaction Profile

Carbon-Fluorine (C-F) bonds are considered the most inert organic functionality and their selective transformation under mild conditions remains challenging. Herein, we report a highly active Pt-Pd nanoalloy as a robust catalyst for the transformation of C-F bonds into C-H bonds at low temperature, a reaction that often required harsh conditions. The alloying of Pt with Pd is crucial to activate C-F bond. The reaction profile kinetics revealed that the major source of hydrogen in the defluorinated product is the alcoholic proton of 2-propanol, and the rate-determining step is the reduction of the metal upon transfer of the <i>beta</i>-H from 2-propanol. DFT calculations elucidated that the key step is the selective oxidative addition of the O-H bond of 2-propanol to a Pd center prior to C-F bond activation at a Pt site, which crucially reduces the activation energy of the C-F bond. Therefore, both Pt and Pd work independently but synergistically to promote the overall reaction

scholarly journals Co-Combustion Studies of Low-Rank Coal and Refuse-Derived Fuel: Performance and Reaction Kinetics

Energies ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3796
Author(s):  
Mudassar Azam ◽  
Asma Ashraf ◽  
Saman Setoodeh Setoodeh Jahromy ◽  
Sajjad Miran ◽  
Nadeem Raza ◽  
...  
Keyword(s):  
Activation Energy ◽  
Waste Management ◽  
Energy Demand ◽  
Power Plants ◽  
Combustion Process ◽  
Isoconversional Methods ◽  
Low Rank ◽  
Heating Rates ◽  
Average Activation Energy ◽  
Refuse Derived Fuel

In connection to present energy demand and waste management crisis in Pakistan, refuse-derived fuel (RDF) is gaining importance as a potential co-fuel for existing coal fired power plants. This research focuses on the co-combustion of low-quality local coal with RDF as a mean to reduce environmental issues in terms of waste management strategy. The combustion characteristics and kinetics of coal, RDF, and their blends were experimentally investigated in a micro-thermal gravimetric analyzer at four heating rates of 10, 20, 30, and 40 °C/min to ramp the temperature from 25 to 1000 °C. The mass percentages of RDF in the coal blends were 10%, 20%, 30%, and 40%, respectively. The results show that as the RDF in blends increases, the reactivity of the blends increases, resulting in lower ignition temperatures and a shift in peak and burnout temperatures to a lower temperature zone. This indicates that there was certain interaction during the combustion process of coal and RDF. The activation energies of the samples were calculated using kinetic analysis based on Kissinger–Akahira–Sunnose (KAS) and Flynn–Wall–Ozawa (FWO), isoconversional methods. Both of the methods have produced closer results with average activation energy between 95–121 kJ/mol. With a 30% refuse-derived fuel proportion, the average activation energy of blends hit a minimum value of 95 kJ/mol by KAS method and 103 kJ/mol by FWO method.

Study on Low Temperature Conduction Mechanism of Al Doped ZnO/SiO2/ P-Si Heterojunction

2021 ◽  
Vol 904 ◽  
pp. 363-368
Author(s):  
Xiao Yan Zhou ◽  
Bang Sheng Yin
Keyword(s):  
Activation Energy ◽  
Impedance Spectroscopy ◽  
Low Temperature ◽  
Grain Boundaries ◽  
Ac Conductivity ◽  
Spray Pyrolysis Method ◽  
Temperature Conductivity ◽  
Calculated Activation Energy ◽  
Doped Zno ◽  
Temperature Conduction

The 3 at% Al doped ZnO thin films were deposited on p-Si substrate with a native SiO2 layer by spray pyrolysis method. Low temperature conduction behaviors were studied by analysis of impedance spectroscopy and low temperature ac conductivity. The results of impedance spectroscopy showed that the grain boundaries contributed to the resistivity of Al doped ZnO/SiO2/p-Si heterojunction. The calculated activation energy was 0.073 eV for grain boundaries. The equivalent circuit to demonstrate the electrical properties of Al doped ZnO/SiO2/p-Si heterojunction was a series connection of two parallel combination circuits of a resistor and a universal capacitor. Low temperature ac conductivity measurements indicated that the conductivity increased with temperature. Low temperature conductivity mechanism was electron conductivity, and the activation energy was 0.086 eV.

DLTS studies of defects produced in n-type silicon by hydrogen implantation at low temperature

2002 ◽  
Vol 744 ◽  
Author(s):  
Takahide Sugiyama ◽  
Masayasu Ishiko ◽  
Shigeki Kanazawa ◽  
Yutaka Tokuda
Keyword(s):  
Activation Energy ◽  
Low Temperature ◽  
Room Temperature ◽  
Reverse Bias ◽  
Thermal Emission ◽  
Sample Temperature ◽  
Zero Bias ◽  
Type Silicon ◽  
Projected Range ◽  
Hydrogen Implantation

ABSTRACTMetastable defects are discovered in hydrogen-implanted n-type silicon. Hydrogen implantation was performed with the energy of 80 keV to a dose of 2×10 cm- at 109 K. After implantation, the sample temperature was raised to room temperature. DLTS measurements were carried out in the temperature range 80–290 K for fabricated diodes. When the sample is reverse-biased at 10V for 10 min at room temperature and then is cooled down to 80 K, three new peaks labeled EM1, EM2 and EM3 appear around 150, 190 and 240 K, respectively. The introduction of metastable defects is found to be characteristic of low temperature implantation. We have evaluated properties of EM1 in detail. EM1 with thermal emission activation energy of 0.29 eV has a peak in concentration around the depth of 0.64 μ m, which corresponds to the projected range of 80 keV hydrogen. EM1 is regenerated with the reverse bias applied around 270 K and is removed with the zero bias around 220 K.

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