Thermal stability of soluble malate dehydrogenase isozymes of subtropical fish belonging to the orders Characiformes, Siluriformes and Perciformes

Electrophoretic thermostability tests of soluble malate dehydrogenases (sMDH) isozymes in tissue extracts of 21 subtropical fish belonging to the orders Characiformes, Siluriformes and Perciformes showed three distinct results. The first, characterized by thermal stability of the slowest-migrating band or A-isoform, was detected in 52% of all species. The second, exhibited in 29% of the species analyzed, had a bidirectionally divergent pattern of their sMDH locus expression, and was characterized by a nondivergent thermostability pattern of both sMDH-A* and B*. In the third category, obtained in 19% of the species studied (the four Siluriformes species), thermostability of the fastest-migrating bands, or B-isoforms, was observed. Comparison of the effects of habitat temperature on the activity of paralogous and orthologous isoforms in tissue extracts of two of these species with different thermostability properties (Leporinus friderici - thermostable sMDH-A*, and Pimelodus maculatus - reverse thermostability properties or reverse electrophoretic pattern), collected during winter and summer months, showed that A and B subunits were present at different quantitative levels and their activities were nearly season independent. Differences in susceptibility to temperature (50°C) of both sMDH loci from tissue extracts of these species were found. In P. maculatus, these susceptibilities helped strengthen one of the hypotheses: the reverse thermostability pattern, where the fastest-migrating band or the B-isoform was the thermostable sMDH. Thus, temperature differences among orthologous homologues of sMDH seem to have occurred in these acclimatized species, where the fastest-migrating band, usually muscle specific and thermolabile in most teleosts, appeared in P. maculatus as the thermostable isoform.

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ROLE OF MOLYBDENUM TRIOXIDE ON THERMAL STABILITY OF POLYANILINE NANOCOMPOSITE

International Journal of Nanoscience ◽

10.1142/s0219581x12500251 ◽

2012 ◽

Vol 11 (03) ◽

pp. 1250025

Author(s):

P. SUJA PREMA RAJINI ◽

R. MURUGESAN ◽

S. PERUMAL

Keyword(s):

Thermal Stability ◽

Weight Loss ◽

Particle Size ◽

Metal Oxide ◽

Molybdenum Trioxide ◽

Spectral Studies ◽

Average Particle ◽

Weight Loss Step ◽

The Third ◽

Thermal Stability Of

Molybdenum trioxide (MoO3) grains were coated with conducting organic polymer of polyaniline. The as-prepared nanocomposite samples were characterized by Fourier transformed infrared (FTIR) spectra, X-ray diffraction (XRD) and Thermogravimetry (TGA). The XRD curves shows that, [Formula: see text] have high crystallinity due to the presence of large number of sharp peaks. From the XRD pattern the particle size is evaluated by using Debye-Scherrer's formula and the average particle size of [Formula: see text] and [Formula: see text] nanocomposites are found to be 46 and 32 nm, respectively. This is clearly observed that the condensed particle size of nanocomposite materials is due to the insertion of metal oxide of molybdenum. The incorporation of metal oxide of MoO3 in polyaniline (Pani) is confirmed by FTIR spectral studies. After de-doping, the characteristic peaks of Pani for all the Pani materials are almost same. This is due to the leaching of metal oxide of MoO3 from Pani. From these observations it is noted that doping–dedoping can also take place in inorganic metal oxides. The thermogram showed a three-step degradation process. The first weight loss step was due to the removal of physisorbed water molecules and moisture. The second minor weight loss step was associated with the removal of dopant from Pani backbone and the slight degradation of benzenoid structure of Pani and their thermal stability is enhanced. The third weight loss step was ascribed to the degradation of quinoid form of Pani. This confirmed the thermal stability of [Formula: see text] nanocomposite system. After degradation above 1000°C, the Pani with MoO3 showed a remaining weight of 8%. This confirmed that incorporation of metal oxide in the Pani nanocomposites is 8%. The enhancement of thermal stability is due to the intercalation of Pani chains into MoO3 in first two step degradation, which is further supported by FTIR and XRD reports. The third step degradation of Pani with MoO3 nanocomposite is loosely bound in organic and inorganic part. Therefore, the organic part is easily decomposed.

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Effect of a Third Element on the Stability of NiSi Thin Films on Si

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.249.127 ◽

2006 ◽

Vol 249 ◽

pp. 127-134 ◽

Cited By ~ 7

Author(s):

Dominique Mangelinck

Keyword(s):

Thin Films ◽

Thermal Stability ◽

Phase Diagrams ◽

High Temperatures ◽

Driving Force ◽

Ternary Phase ◽

The Third ◽

Ternary Phase Diagrams ◽

The Stability ◽

Thermal Stability Of

The effect of Pt and Ge on the stability of NiSi films has been examined. The addition of a small amount of Pt (5 at%) in the Ni film increases the disilicide nucleation temperature to 900oC leading to a better stability of NiSi at high temperatures. For Ni films on Si1-xGex with x=0.29 and 0.58, no NiSi2 was found after annealing at 850°C. The increase in thermal stability of NiSi has been explained in terms of nucleation concept. Calculated ternary phase diagrams allow to understand the effect of the third element (Pt or Ge) on the driving force for nucleation. The redistribution of this element can also be explained with the ternary phase diagrams.

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Thermal stability of the molecular forms of guinea-pig skeletal muscle cytoplasmic malate dehydrogenase and kinetic mechanism of the thermostable form

International Journal of Biochemistry ◽

10.1016/0020-711x(81)90089-6 ◽

1981 ◽

Vol 13 (3) ◽

pp. 355-364 ◽

Cited By ~ 3

Author(s):

A. Sorribas ◽

J. Puig ◽

A. Cortes ◽

J. Bozal

Keyword(s):

Skeletal Muscle ◽

Thermal Stability ◽

Guinea Pig ◽

Malate Dehydrogenase ◽

Kinetic Mechanism ◽

Molecular Forms ◽

Thermal Stability Of

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A Single Amino Acid Mutation Enhances the Thermal Stability of Escherichia coli Malate Dehydrogenase

European Journal of Biochemistry ◽

10.1111/j.1432-1033.1994.tb20018.x ◽

1994 ◽

Vol 224 (1) ◽

pp. 249-255 ◽

Cited By ~ 13

Author(s):

Christopher R. Goward ◽

Julie Miller ◽

David J. Nicholls ◽

Laurence I. Irons ◽

Michael D. Scawen ◽

...

Keyword(s):

Escherichia Coli ◽

Thermal Stability ◽

Amino Acid ◽

Malate Dehydrogenase ◽

Single Amino Acid ◽

Amino Acid Mutation ◽

Single Amino Acid Mutation ◽

Thermal Stability Of

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Large Improvement in the Thermal Stability of a Tetrameric Malate Dehydrogenase by Single Point Mutations at the Dimer–Dimer Interface

Journal of Molecular Biology ◽

10.1016/j.jmb.2004.06.079 ◽

2004 ◽

Vol 341 (5) ◽

pp. 1215-1226 ◽

Cited By ~ 28

Author(s):

Alexandra Bjørk ◽

Bjørn Dalhus ◽

Dimitrios Mantzilas ◽

Reidun Sirevåg ◽

Vincent G.H. Eijsink

Keyword(s):

Thermal Stability ◽

Malate Dehydrogenase ◽

Single Point ◽

Point Mutations ◽

Dimer Interface ◽

Single Point Mutations ◽

Large Improvement ◽

Thermal Stability Of

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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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