Thermal stability of Li2O–SiO2–TiO2 gels evaluated by the induction period of crystallization

The dependence of the induction period of crystallization on the supercooling was determined for the Ca(NO3)2-ethylene glycol system at mole fractions of the former from 0 to 0.049, and treated in terms of the TTT (Time-Temperature-Transformation) diagram. Addition of Ca(NO3)2 to ethylene glycol brings about a substantial increase in the critical induction period of crystallization. The thermal stability of glasses is discussed in terms of the shape and position of the TTT curves.

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Thermal stability of glass evaluated by the induction period of crystallization

Thermochimica Acta ◽

10.1016/j.tca.2004.09.016 ◽

2005 ◽

Vol 428 (1-2) ◽

pp. 11-14 ◽

Cited By ~ 19

Author(s):

P. Šimon ◽

K. Nemčeková ◽

E. Jóna ◽

A. Plško ◽

D. Ondrušová

Keyword(s):

Thermal Stability ◽

Induction Period ◽

Thermal Stability Of

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The Role of Sulfur in the Thermal Stability of Jet Fuel

Volume 2: Coal, Biomass and Alternative Fuels; Combustion and Fuels; Oil and Gas Applications; Cycle Innovations ◽

10.1115/99-gt-298 ◽

1999 ◽

Author(s):

David W. Naegeli

Keyword(s):

Thermal Stability ◽

Induction Period ◽

Jet Fuel ◽

Sulfur Compounds ◽

Inhibition Mechanism ◽

Organic Base ◽

Oxidation Inhibitor ◽

Acid Catalyzed ◽

Thermal Stability Of

The autoxidation of Jet A, dodecane, and a dodecane-15%-cumene blend doped with sulfur compounds were studied at 433 K. Oxygen, hydro peroxide and soluble gum were monitored during the autoxidation. Dodecane, cumene, and the dodecane-15%-cumene blend autoxidized rapidly, while Jet A had an induction period followed by a relatively slow post autoxidation. The results suggest that an inhibitor formed early in the post autoxidation of Jet A. Gum formed in the autoxidation of Jet A, whereas none was detected in dodecane, cumene, or dodecane-15% cumene. However, gum was detected in dodecane and dodecane-15% cumene doped with thiols and disulfides. Alkyl thiols and disulfides reduced the rate of autoxidation of dodecane, and there was an induction period in the formation of gum. Traces of sulfur (≈4 ppm) inhibited the autoxidation of dodecane-15% cumene in a way that resembled the post autoxidation of Jet A. Adding an organic base increased the rate of post autoxidation in Jet A and prevented formation of the oxidation inhibitor. An inhibition mechanism is proposed in which phenois are formed via acid-catalyzed decomposition of benzylic hydro peroxides.

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Induction period of crystallization of zinc chloride solutions in ethylene glycol

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19902428 ◽

1990 ◽

Vol 55 (10) ◽

pp. 2428-2431 ◽

Cited By ~ 1

Author(s):

Ivo Sláma ◽

Jarmila Malá

Keyword(s):

Thermal Stability ◽

Ethylene Glycol ◽

Induction Period ◽

Zinc Chloride ◽

Supercooled Liquids ◽

Chloride Solutions ◽

Transformation Diagram ◽

Temperature Transformation ◽

Thermal Stability Of

The dependence of the induction period of crystallization on the supercooling was examined for the ZnCl2-ethylene glycol system at mole fractions of the salt from 0 to 0.07, and treated in terms of the TTT (Time-Temperature-Transformation) diagram. The critical induction period of crystallization increases substantially on the addition of ZnCl2 to ethylene glycol. The thermal stability of supercooled liquids is discussed in terms of the shape and position of the TTT curves.

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The Ordered Phase Formation in Ti-Al-Ga Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069193 ◽

1970 ◽

Vol 28 ◽

pp. 440-441

Author(s):

Shiro Fujishiro ◽

Harold L. Gegel

Keyword(s):

Thermal Stability ◽

High Temperature ◽

Titanium Alloys ◽

Growth Kinetics ◽

Stoichiometric Composition ◽

Good Potential ◽

Alpha Titanium ◽

Cold Rolled ◽

Kinetics Of ◽

Thermal Stability Of

Ordered-alpha titanium alloys having a DO19 type structure have good potential for high temperature (600°C) applications, due to the thermal stability of the ordered phase and the inherent resistance to recrystallization of these alloys. Five different Ti-Al-Ga alloys consisting of equal atomic percents of aluminum and gallium solute additions up to the stoichiometric composition, Ti3(Al, Ga), were used to study the growth kinetics of the ordered phase and the nature of its interface.The alloys were homogenized in the beta region in a vacuum of about 5×10-7 torr, furnace cooled; reheated in air to 50°C below the alpha transus for hot working. The alloys were subsequently acid cleaned, annealed in vacuo, and cold rolled to about. 050 inch prior to additional homogenization

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Microstructure studies of tungsten silicide schottky contacts on Gaas

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126445 ◽

1987 ◽

Vol 45 ◽

pp. 328-329

Author(s):

Yih-Cheng Shih ◽

E. L. Wilkie

Keyword(s):

Thermal Stability ◽

Field Effect Transistors ◽

Schottky Contact ◽

Schottky Contacts ◽

Excellent Thermal Stability ◽

Barrier Heights ◽

Gaas Substrates ◽

Film Adhesion ◽

Threshold Voltages ◽

Thermal Stability Of

Tungsten silicides (WSix) have been successfully used as the gate materials in self-aligned GaAs metal-semiconductor-field- effect transistors (MESFET). Thermal stability of the WSix/GaAs Schottky contact is of major concern since the n+ implanted source/drain regions must be annealed at high temperatures (∼ 800°C). WSi0.6 was considered the best composition to achieve good device performance due to its low stress and excellent thermal stability of the WSix/GaAs interface. The film adhesion and the uniformity in barrier heights and ideality factors of the WSi0.6 films have been improved by depositing a thin layer of pure W as the first layer on GaAs prior to WSi0.6 deposition. Recently WSi0.1 has been used successfully as the gate material in 1x10 μm GaAs FET's on the GaAs substrates which were sputter-cleaned prior to deposition. These GaAs FET's exhibited uniform threshold voltages across a 51 mm wafer with good film adhesion after annealing at 800°C for 10 min.

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