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The Sn−Ti−Zn ternary phase diagram has been constructed using the CALPHAD technique. The Ti−Zn binary system phase boundaries were determined using differential scanning calorimetry and the solid-liquid diffusion couples method. In addition, the formation energy of some stoichiometric compounds was obtained using first-principle band energy calculations. For the ternary system, some alloys were prepared by equilibration at 600 or 700 °C, and the compositions of the precipitates were analyzed using electron probe microanalysis. Thermodynamic assessment of the Ti−Zn and Sn−Ti−Zn systems was performed based on the experimental information and by adopting reported values of the thermodynamic properties of the Sn−Zn and Sn−Ti binary systems. Microstructural observation showed that Sn3Ti5Zn12 exists in the ternary system. Seven types of invariant reaction on the Sn-rich liquidus surface of the ternary system are predicted by the phase diagram calculations. The ternary eutectic point falls at 0,0009 mass% Ti and 8.69 mass% Zn, at T=192.40°C, which is slightly lower than the calculated eutectic point of Sn−Zn binary alloy ( T=192.41°C). Based on these results, a nonequilibrium solidification process using the Scheil model was simulated. [ABSTRACT FROM AUTHOR]

A new Al2O3/Er3Al5O12(EAG)/ZrO2 ternary MGC (Melt Growth Composite) with a novel microstructure has been fabricated by unidirectional solidification. This ternary MGC has a microstructure consisting of continuous networks of single-crystal Al2O3, single-crystal EAG and fine cubic-ZrO2 phases without grain boundaries. The ternary MGC has also characteristic dimensions of the microstructure of around 2-4 µ m for EAG phases, around 2-4 µ m for Al2O3 phases reinforced with around 0.4-0.8 µ m cubic-ZrO2 phases. No amorphous phases are formed at interfaces between phases in the ternary MGC. The ternary MGC’s flexural strength at 1873 K is approximately 700 MPa, more than twice the 330 MPa of the Al2O3/EAG binary MGC. The fracture manner of the Al2O3/EAG/ZrO2 ternary MGC at 1873 K shows the same intergranular fracture as the Al2O3/EAG binary MGC, but is significantly different from the transgranular fracture of the sintered ceramic. [ABSTRACT FROM AUTHOR]

Three subfamilies of the En/Spm-type transposable element of carrot, Tdc A, B, and C, were characterized. It was supposed that the Tdc A subfamily may include autonomous elements which can produce transposases. Tdc B elements are defective, but still generate transcripts containing mutant open reading frame (ORF) sequences for transposases. The single member of the Tdc C group recovered seems to be a pseudogene. The sequences of the transposase ORFs of Tdc A and Tdc B elements are more highly conserved than those of the 5´ and 3´ untranslated regions and introns, as is found in other structural genes that are subject to selection. These observations indicate that the mutations in the nucleotide sequences of the Tdc elements occurred in the host genome. However, the mutations in the 5´ and 3´ untranslated regions and introns, which may not be sufficient to prevent transposition, accumulated in autonomous elements, which could transpose and produce copies. When the reproduction rate and the rate of disabling mutations reached an equilibrium, that is, when the birth rate of the transposable elements in the genome equalled the death rate, the population of elements achieved a stationary state in the genome, and could thus survive. [ABSTRACT FROM AUTHOR]

New Al2O3/Y3Al5O12(YAG)/ZrO2 ternary Melt Growth Composites (MGCs) with a novel microstructure have been fabricated by unidirectional solidification. These MGCs displayed superior high-temperature strength characteristics. The flexural strength increases progressively in the range 650–800 MPa with a rise in temperature from room temperature up to 1873 K. These excellent high-temperature characteristics are closely linked to such factors as: a microstructure consisting of three-dimensionally continuous and complexly entangled single-crystal Al2O3 with a hexagonal structure, single-crystal YAG with a garnet structure and fine ZrO2 with a cubic structure; characteristic dimensions of the microstructure of Al2O3/YAG/ZrO2 ternary eutectic ceramics of around 2–3 μm for YAG, around 2–3 μm for Al2O3 and around 0.4–0.8 μm for ZrO2; and the fact that no amorphous phase is formed at interfaces between any of the phases. [ABSTRACT FROM AUTHOR]

A thermodynamic analysis of the phase equilibria in the Ni-Si-B ternary system was conducted. A regular solution approximation based on a sublattice model was adopted to describe the Gibbs energies for the individual phases in the binary and ternary systems. A set of thermodynamic parameters for the individual phases was evaluated from literature data on phase boundaries and thermochemical properties. The optimized parameters reproduced the experimental data, for the most part, satisfactorily. However, in the calculated isothemal section at 850 °C, phase equilibria between the fcc phase and Ni6Si2B or Ni3Si( β 1) and Ni6Si2B were found instead of the experimentally observed equilibria between Ni3Si( β 1) and Ni3B or Ni5Si2( γ) and Ni3B. Further, in the primary crystal surface for the fcc phase, the calculated liquidus temperatures were higher than the reported values by approximately 80 °C. Therefore, it is considered that the fcc phase evaluated in the Ni-Si system by Lindhólm and Sundman is too stable. [ABSTRACT FROM AUTHOR]

Thermodynamic constraints are introduced to describe Gibbs energies for a CALPHAd-type calculation; available data on the pure elements and phase diagram data were used to optimize relevant parameters. Constraints can be applied to the mathematical description of Gibbs energies for three regions of phase diagrams: those with complete miscibility, those with an intermetallic compound, and those with a miscibility gap. The authors examine the present thermodynamic constraints in construction of Gibbs energies for the Ag-Pd, Mg-Sn, and Au-Ni binary systems as typical examples for these cases. The optimization procedure for obtaining parameters for models of the Gibbs energies is divided mainly into four steps to reach the final parameters, and the results obtained in each step are compared in detail. The authors also present assessed parameters for the Gibbs energies concerning these three binary systems by the available thermodynamic data in addition to the phase diagram data with the present thermodynamic constraints. [ABSTRACT FROM AUTHOR]

Electrophysiological methods were applied to 160 healthy adult male guinea pigs in order to investigate the effects of pure-tone exposure for 24 h on the inner ear. A reduction in cochlear microphonics (CM), action potential (AP) and endocochlear potential was observed following exposure to 110 dB at 100 Hz, 100 dB at 200 and 600 Hz and 95 dB at 2 kHz. The observed K endolymphatic concentration during 40 min anoxia remained unchanged. In contrast K+ decreased in control animals and following exposure to pure tones varying from 110 dB at 60 Hz to 85 dB at 2 kHz. These findings indicate that high frequency tones have a greater effect on inner ear functions than those of lower frequency, decreasing the maximum output voltage of CM and AP but not changing K endolymphatic concentration. [ABSTRACT FROM AUTHOR]

The solubility of carbon in bcc Fe and fcc Co-Ni alloys has been examined by the diffusion couple method, and a thermodynamic analysis of the data has been carried out, taking into account the effect of magnetic transition. It has been detected that the solubility slightly deviates from the ordinary linear relation between log [pct C] and 1/T below the Curie point. The deviation has been well explained by the magnetic effect on the Gibbs energy for the bcc Fe-C and fcc Co-Ni-C phases. [ABSTRACT FROM AUTHOR]

Carnivorous plants exploit animals as a nutritional source and have inspired long-standing questions about the origin and evolution of carnivory-related traits. To investigate the molecular bases of carnivory, we sequenced the genome of the heterophyllous pitcher plant Cephalotus follicularis, in which we succeeded in regulating the developmental switch between carnivorous and non-carnivorous leaves. Transcriptome comparison of the two leaf types and gene repertoire analysis identified genetic changes associated with prey attraction, capture, digestion and nutrient absorption. Analysis of digestive fluid proteins from C. follicularis and three other carnivorous plants with independent carnivorous origins revealed repeated co-options of stress-responsive protein lineages coupled with convergent amino acid substitutions to acquire digestive physiology. These results imply constraints on the available routes to evolve plant carnivory.