Single Crystals of Ice Grown from KCl Solution and Their Dielectric Properties

1973 ◽  
Vol 51 (10) ◽  
pp. 1045-1052 ◽  
Author(s):  
Norikazu Maeno
Keyword(s):  
Activation Energy ◽  
Dielectric Properties ◽  
Crystal Lattice ◽  
Single Crystals ◽  
Low Frequency ◽  
Distribution Coefficients ◽  
Square Root ◽  
Dielectric Polarization ◽  
Kcal Mole ◽  
Upper Limit

Single crystals of ice were grown from KCl solution and their dielectric properties were investigated as functions of concentration, frequency, and temperature. It was found that a limited amount of chlorine was incorporated into the crystal lattice of ice but no trace of potassium. The upper limit of the substitutional incorporation of chlorine was approximately 1 × 10−4M(g moles/1). The distribution coefficients of the solutes were obtained as functions of the KCl concentration of the mother solution.The static dielectric constant of the single crystals of ice decreased due to the chlorine incorporation and the activation energy of its dielectric relaxation was reduced to 5.8 kcal/mole. The low-frequency conductivity increased with the square root dependence upon the chlorine concentration, and its activation energy was 6.1 kcal/mole. The mechanism of the dielectric polarization and conduction was discussed in relation to the defects introduced by chlorine built in the crystal lattice.

scholarly journals Dielectric, Thermal and FTIR Studies of Cobalt Doped Magnesium Hydrogen Maleate Hexahydrate Single Crystals

2011 ◽  
Vol 8 (1) ◽  
pp. 91-96
Author(s):  
B. Rajagopal ◽  
M. V. Ramana ◽  
A. V. Sarma
Keyword(s):  
Activation Energy ◽  
Dielectric Constant ◽  
Dielectric Properties ◽  
Melting Point ◽  
Transition Metal ◽  
Single Crystals ◽  
Loss Tangent ◽  
Transition Metal Ions ◽  
Ftir Studies ◽  
First Time

Present work reports the dielectric, thermal and FTIR studies of Co2+: MHMH single crystal for the first time. The influence of addition of transition metal ions on the dielectric properties, like dielectric constant, loss tangent,a.c. conductivity and activation energy of these crystals was discussed. FTIR studies confirm the presence of carboxylate ions. The melting point of the sample and final product after decomposition are studied using TG/DTA.

Nachweis von strukturellen L-Defekten im innerkristallinen Wasser von hydratierten Vermikuliteinkristallen mittels dielektrischer Messungen / Detection of Structural L-Defects in Intracrystalline Water of Vermiculites by Dielectric Measurements

1973 ◽  
Vol 28 (3-4) ◽  
pp. 140-147 ◽  
Author(s):  
Günter Schön ◽  
Armin Weiss
Keyword(s):  
Activation Energy ◽  
Single Crystals ◽  
Water Molecules ◽  
Dielectric Measurements ◽  
Kcal Mole ◽  
Water Layers

Homoionic single crystals of vermiculite in different hydration stages (isolated water molecules, discrete monomolecular or bimolecular water layers respectively) have been used for dielectric measurements within the frequency of 30 Hz and 10 MHz. The results are interpreted by the diffusion of isolated structural L-defects. The activation energy of the process has been determined to be 2.3 kcal/mole.

Gas phase photochlorination of perfluorocyclohexene

1969 ◽  
Vol 47 (6) ◽  
pp. 1067-1069 ◽  
Author(s):  
J. J. Cosa ◽  
C. A. Vallana ◽  
E. H. Staricco
Keyword(s):  
Activation Energy ◽  
Quantum Yield ◽  
Gas Phase ◽  
Photochemical Reaction ◽  
Total Pressure ◽  
Square Root ◽  
Kcal Mole ◽  
Kinetics Of

The kinetics of the gas phase photochemical reaction between perfluorocyclohexene and chlorine was studied between 10 and 50 °C. The system was irradiated with light of 4360 Å. The rate of the photochlorination was independent of the perfluorocyclohexene pressure and of the total pressure. It was found to be proportional to the first power of the pressure of Cl2 and to the square root of the intensity of absorbed light. At 30 °C, the quantum yield was found to be 200 when the initial Cl2 pressure was 100 Torr, and intensity of light absorbed 9.89 × 10−9 einstein l−1s−1.An activation energy of 5.1 kcal/mole could be assigned to the reaction C6F10Cl + Cl2.

scholarly journals Investigation of Electronic Conductivity in PbI2:Hf Single Crystals

2019 ◽  
Vol 20 (4) ◽  
pp. 396-400
Author(s):  
T.V. Furs ◽  
O.I. Hulaj ◽  
V.Ya. Shemet
Keyword(s):  
Activation Energy ◽  
Single Crystal ◽  
Single Crystals ◽  
Electronic Conductivity ◽  
Hole Conductivity ◽  
Electron Hole ◽  
Upper Limit ◽  
Increasing Temperature ◽  
P Type ◽  
Current Potential

A study of the electron-hole conductivity in PbI2 single crystals doped with Hf (0.2 wt %) was conducted using the Wagner polarization cell method. The influence of the Hf alloying admixture (0.2 mass%) on the nature and parameters of lead diiodide’s electronic conductivity has been analyzed. Basing on the received current-potential dependences, p-type conductivity of a single crystal PbI2:Hf was established. The hole conductivity values (sро) were determined in the studied temperature range allowing to construct temperature dependence. The sро value for single crystal PbI2:Hf increased responsively to increasing temperature. For PbI2 and PbI2:Hf, a comparative analysis of the electron-hole conductivity was carried out. This investigation allowed determining the activation energy sро reduction from 0.47 eV to 0.32 eV due to hafnium doping. Consequently, the presence of Hf admixture in PbI2 crystals causes new impurity acceptor levels located at a distance of 0.64 eV from the upper limit of the valence zone.

Über Reaktionen zwischen Phosphortrichlorid und Cyclohexen unter dem Einfluß von Y-Strahlung und von Wärme

1964 ◽  
Vol 19 (11) ◽  
pp. 999-1005 ◽  
Author(s):  
K. Wunder ◽  
H. Drawe ◽  
A. Henglein
Keyword(s):  
Activation Energy ◽  
Dose Rate ◽  
Phosphorus Trichloride ◽  
Square Root ◽  
Kcal Mole ◽  
Chain Reaction ◽  
Rate Determining Step ◽  
Γ Rays ◽  
G Value

1-chlorocyclohexyl-phosphorus dichloride is formed in a Kharasch type chain reaction when γ-rays act on mixtures of phosphorus trichloride and cyclohexene. The G-value is proportional to the reciprocal square root of the dose rate and reaches a maximum at 100°C. The activation energy of the rate determining step PCl2C6H10 · +PCl3→PCl2C6H10Cl+PCl2 · was found to amount to 6, 7 kcal/mole. At higher temperatures, the yield strongly decreases since another chain reaction predominates which produces cyclohexyl-phosphorus dichloride. The two chains have a common propagation step. 1-chlorocyclohexyl-phosphorus dichloride and cyclohexyl-phosphorus dichloride are also thermally formed at temperatures above about 150°C.

Dielectric Behaviour in the MHz range of cis-bis (glycynato)Cu(II) monohydrate and (glycylglycinato)Cu(II) trihydrate in Water

1976 ◽  
Vol 31 (9) ◽  
pp. 1085-1088 ◽  
Author(s):  
P. U. Sakellaridis ◽  
E. K. Karageorgopoulos
Keyword(s):  
Activation Energy ◽  
Aqueous Solution ◽  
Dipole Moment ◽  
Relaxation Time ◽  
Dielectric Properties ◽  
Charge Separation ◽  
Rotational Relaxation ◽  
Kcal Mole ◽  
Dielectric Absorption ◽  
Molecular Radius

Abstract The dielectric properties of Cu(gly)2 and Cu(glygly) in diluted aqueous solution were examined in the MHz range at 273 to 313 K. The complexes exhibit dielectric absorption in the ranges 5.09X107 to 9.34X107 Hz and 4.63X107 to 8.01X107 Hz, respectively, depending on concentration and temperature. This absorption was attributed to rotational relaxation of the unhydrated and monohydrated complexes. The following data for the two complexes in solution at 293 K have been obtained, respectively: dipole moment 19.3 D and 34.0 D, charge separation 2.01 A and 3.54 Å, relaxation time 2.3X10-9 sec and 2.6X10-9 sec, molecular radius 6.36 Å and 6.47 Å, activation energy for the relaxation process 5.6 kcal mole-1 for both complexes.

scholarly journals Fabrication and Electrical Characterization of Translucent Bi12TiO20Ceramics

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
D. J. Santos ◽  
L. B. Barbosa ◽  
R. S. Silva ◽  
Z. S. Macedo
Keyword(s):  
Activation Energy ◽  
Grain Size ◽  
Dielectric Properties ◽  
Single Crystals ◽  
Optical Transmission ◽  
Electrical Characterization ◽  
High Density ◽  
Average Grain Size ◽  
Electrical And Dielectric Properties

The production of high-density Bi12TiO20ceramics, their transmission spectrum, and impedance features are reported. The samples were synthesized at 700°C/6 h and sintered at 800°C/3 h. This procedure yielded translucent ceramics with relative density of99.2±0.5% and average grain size of3.1±1.6 μm. Samples with 0.5 mm thickness were translucent with optical transmission of about 30% at 800 nm. The electrical and dielectric properties of the high-density ceramics were studied and compared with those measured for samples with lower density and also with the literature about Bi12TiO20single crystals. The activation energy for the conduction process in high-density ceramic was 0.99 eV, and the dielectric permittivity was 40 at 200°C. These values are comparable to those reported for single crystals.

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