THE CONDUCTANCE OF MOLTEN LITHIUM CHLORATE AND THE EFFECT OF ADDITIONS OF TRACES OF NONELECTROLYTES ON THE CONDUCTANCE

1962 ◽  
Vol 40 (5) ◽  
pp. 890-895 ◽  
Author(s):  
A. N. Campbell ◽  
E. M. Kartzmark ◽  
D. F. Williams

The specific conductance of pure molten lithium chlorate between 130 and 145 °C was determined and an activation energy of conductance deduced. Additions of substances having various dielectric constants were made to molten lithium chlorate and the conductances determined. These additions were: (a) water, 0–6% by weight; (b) nitrobenzene, 0–0.4% by weight; (c) methyl alcohol, 0–1.25% by weight. The results are discussed.

1964 ◽  
Vol 42 (8) ◽  
pp. 1984-1995 ◽  
Author(s):  
A. N. Campbell ◽  
D. F. Williams

The electrical conductance and its temperature dependence of molten lithium chlorate have been determined. Similar results have been obtained for lithium chlorate melts containing small quantities of methyl alcohol, propyl alcohol, lithium nitrate, lithium hydroxide, and water.The results obtained, taken in conjunction with the results of previous work, all indicate that the melt is complex. There is probably considerable association and this is especially evident slightly above the melting point: at temperatures in this region the temperature change of the properties of the lithium chlorate melt is greatest.The activation energy of conductance is approximately the same as the activation energy of viscous flow, for pure lithium chlorate melt and for mixtures of lithium chlorate with lithium nitrate. From this it appears that the melt constituents are not principally the simple ions, but that some form of cohesion exists between the simple constituents of the melt.The addition of water to the lithium chlorate melt causes the melt properties to alter considerably, especially the transport properties, viscosity and conductance. It is suggested that these changes may in part be due to a breakup of the structural entities of the pure melt, though the increase in electrical conductance cannot be completely explained in this way. A cryoscopic investigation seems to indicate that water is •not present as such in the melt.


1975 ◽  
Vol 53 (9) ◽  
pp. 1263-1274 ◽  
Author(s):  
Jean-Pol Dodelet ◽  
Gordon R. Freeman

The free ion yields in X irradiated ethers are larger than those in alkanes because the dielectric constants of the former liquids are greater than those of the latter. The relative increase of the free ion yield with temperature is smaller in ethers than in alkanes because the dielectric constants decrease more rapidly with increasing temperature in the former. The density normalized penetration range (thermalization length) bGPd of the secondary electrons in dimethyl ether (DME) is 3.5 × 10−7 g/cm2. As the length of the n-alkyl groups on the ether is increased bGPd increases towards the value obtained for long chain n-alkanes, 4.5 × 10−7 g/cm2. Electron mobilities ue showed two types of behavior: (i) at low temperatures ue approaches a value of about 2u−, where u− is the mobility of the anions formed in the irradiated liquid; (ii) at higher temperatures the ratio ue/u− increases with temperature, and equals 21 in di-n-butyl ether (DBE) at 375 K. The activation energy of electron migration at low temperatures (ion-like mechanism) is similar to that of ion migration, 2–3 kcal/mol, while at high temperatures it increases to ∼6 kcal/mol. The larger activation energy is attributed to thermal excitation of electrons from the solvated state into a conduction band, and is equal to one-half of the optical excitation energy of the solvated electrons. Electrons in water, alcohols, and ammonia at 300 K migrate by the ion-like mechanism. Electrons in alkanes migrate almost exclusively by the conduction band mechanism. A plot of the Arrhenius temperature coefficient of electron mobility against mobility in different liquids at a given temperature displays a maximum which is temperature dependent.


2012 ◽  
Vol 9 (2) ◽  
pp. 179-189 ◽  
Author(s):  
K. YADAIAH ◽  
J. KRISHNAIAH ◽  
VASUDEVA REDDY ◽  
M. NAGABHUSHANAM

Dielectric permittivity has been an important property of binary and mixed semiconductor materials as it is closely related to the studies on polarization and relaxation mechanisms. Therefore, dielectric properties of (CdSe)1-X(ZnS)X mixed semiconductors are studied at different frequencies. The mixed semiconductor samples used in the study are grown by controlled co-precipitation method. From these studies ac conductivity, static and optical dielectric constants, relaxation times and activation energy of dipole relaxation are determined. The variation of dielectric constant with frequency and composition of the sample was explained on the basis of Koops grain boundary mechanism.


2010 ◽  
Vol 434-435 ◽  
pp. 253-255
Author(s):  
Jing Han You ◽  
Xiao Yang Gong ◽  
Tong Wei Li ◽  
Qing Dong Chen ◽  
Li Ben Li

CaCu3Ti4O12 ceramics were prepared by the traditional solid-state reaction method and the dielectric properties were investigated, the activation energy and relaxation time factor of the samples were calculated. Debye relaxation theory was attempted to analyze the experimental datum, the static and high-frequency dielectric constants were obtained according to Cole-Cole spectra. The temperature dependence of the dielectric constant of CaCu3Ti4O12 were fitted by computer and the theoretical results nearly agree with experimental results.


1950 ◽  
Vol 72 (7) ◽  
pp. 3293-3294 ◽  
Author(s):  
John H. LaRochelle ◽  
Arthur A. Vernon

Author(s):  
Julio H. Garcia ◽  
Janice P. Van Zandt

Repeated administration of methyl alcohol to Rhesus monkeys (Maccaca mulata) by intragastric tube resulted in ultrastructural abnormalities of hepatocytes, which persisted in one animal twelve weeks after discontinuation of the methyl alcohol regime. With dosages ranging between 3.0 to 6.0 gms. of methanol per kg. of body weight, the serum levels attained within a few hours averaged approximately 475 mg. per cent.


Author(s):  
R. L. Lyles ◽  
S. J. Rothman ◽  
W. Jäger

Standard techniques of electropolishing silver and silver alloys for electron microscopy in most instances have relied on various CN recipes. These methods have been characteristically unsatisfactory due to difficulties in obtaining large electron transparent areas, reproducible results, adequate solution lifetimes, and contamination free sample surfaces. In addition, there are the inherent health hazards associated with the use of CN solutions. Various attempts to develop noncyanic methods of electropolishing specimens for electron microscopy have not been successful in that the specimen quality problems encountered with the CN solutions have also existed in the previously proposed non-cyanic methods.The technique we describe allows us to jet polish high quality silver and silver alloy microscope specimens with consistant reproducibility and without the use of CN salts.The solution is similar to that suggested by Myschoyaev et al. It consists, in order of mixing, 115ml glacial actic acid (CH3CO2H, specific wt 1.04 g/ml), 43ml sulphuric acid (H2SO4, specific wt. g/ml), 350 ml anhydrous methyl alcohol, and 77 g thiourea (NH2CSNH2).


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