The Effect of Using Different Y2O3 Layers on the Activation Energy and Irreversibility Line of MPMG YBCO Bulk at 1050 °C Growth Temperature

2018 ◽  
Vol 31 (10) ◽  
pp. 3167-3174
Author(s):  
Sedat Kurnaz ◽  
Bakiye Çakır ◽  
Alev Aydıner
Keyword(s):  
Activation Energy ◽  
Growth Temperature ◽  
Irreversibility Line ◽  
Ybco Bulk

The effect of growth temperature on the irreversibility line of MPMG YBCO bulk with Y 2 O 3 layer

Cryogenics ◽  
2017 ◽  
Vol 85 ◽  
pp. 51-57 ◽  
Author(s):  
Sedat Kurnaz ◽  
Bakiye Çakır ◽  
Alev Aydıner
Keyword(s):  
Growth Temperature ◽  
Irreversibility Line ◽  
Ybco Bulk

The balance between RuBP carboxylation and RuBP regeneration: a mechanism underlying the interspecific variation in acclimation of photosynthesis to seasonal change in temperature

2005 ◽  
Vol 32 (10) ◽  
pp. 903 ◽  
Author(s):  
Yusuke Onoda ◽  
Kouki Hikosaka ◽  
Tadaki Hirose
Keyword(s):  
Activation Energy ◽  
Photosynthetic Rate ◽  
Growth Temperature ◽  
Temperature Response ◽  
Interspecific Variation ◽  
Fagus Crenata ◽  
Interspecific Difference ◽  
Photosynthetic Rates ◽  
Interspecific Differences ◽  
Arrhenius Function

The ratio of the capacities of ribulose-1,5-bisphosphate (RuBP) regeneration to RuBP carboxylation (Jmax / Vcmax) (measured at a common temperature) increases in some species when they are grown at lower temperatures, but does not increase in other species. To investigate the mechanism of interspecific difference in the response of Jmax / Vcmax to growth temperature, we analysed the temperature dependence of Vcmax and Jmax in Polygonum cuspidatum and Fagus crenata with the Arrhenius function. P. cuspidatum had a higher ratio of Jmax / Vcmax in spring and autumn than in summer, while F. crenata did not show such change. The two species had a similar activation energy for Vcmax (EaV) across seasons, but P. cuspidatum had a higher activation energy for Jmax (EaJ) than F. crenata. Reconstruction of the temperature response curve of photosynthesis showed that plants with an inherently higher EaJ / EaV (P. cuspidatum) had photosynthetic rates that were limited by RuBP regeneration at low temperatures and limited by RuBP carboxylation at high temperatures, while plants with an inherently lower EaJ / EaV (F. crenata) had photosynthetic rates that were limited solely by RuBP carboxylation over the range of temperatures. These results indicate that the increase in Jmax / Vcmax at low growth temperatures relieved the limitation of RuBP regeneration on the photosynthetic rate in P. cuspidatum, but that such change in Jmax / Vcmax would not improve the photosynthetic rate in F. crenata. We suggest that whether or not the Jmax / Vcmax ratio changes with growth temperature is attributable to interspecific differences in EaJ / EaV between species.

scholarly journals Thermal acclimation of photosynthetic activity and Rubisco content in two hybrid poplar clones

2018 ◽  
Author(s):  
Lahcen Benomar ◽  
Mohamed. Taha Moutaoufik ◽  
Raed Elferjani ◽  
Nathalie Isabel ◽  
Annie DesRochers ◽  
...  
Keyword(s):  
Activation Energy ◽  
Stomatal Conductance ◽  
Growth Temperature ◽  
Dark Respiration ◽  
Hybrid Poplar ◽  
Rubisco Activase ◽  
Thermal Acclimation ◽  
Warm Condition ◽  
Poplar Clones ◽  
Two Hybrid

AbstractThe mechanistic bases of thermal acclimation of net photosynthetic rate (An) are still difficult to discern and empirical research remains limited, particularly for hybrid poplar. In the present study, we examined the contribution of a number of biochemical and biophysical traits on thermal acclimation of An for two hybrid poplar clones. We grew cuttings of Populus maximowiczii × Populus nigra (M×N) and Populus maximowiczii × Populus balsamifera (M×B) clones under two day/night temperature of 23°C/18°C and 33°C /27°C and under low and high soil nitrogen level. After 10 weeks, we measured leaf RuBisCO and RuBisCO activase (RCA) amounts and the temperature response of An, dark respiration (Rd), stomatal conductance, (gs), maximum carboxylation rate of CO2 (Vcmax) and photosynthetic electron transport rate (J). Results showed that a 10°C increase in growth temperature resulted in a shift in thermal optimum (Topt) of An of 6.2±1.6 °C and 8.0±1.2 °C for clone M×B and M×N respectively, and an increased An and gs at the growth temperature for clone M×B but not M×N. RuBisCO amount was increased by N level but was insensitive to growth temperature while RCA amount and the ratio of its short to long isoform was stimulated by warm condition for clone M×N and at low N for clone M×B. The activation energy of Vcmax and J decreased under warm condition for clone M×B and remain unchanged for clone M×N. Our study demonstrated the involvement of both RCA, activation energy of Vcmax and stomatal conductance in thermal acclimation of An.

THE IRREVERSIBILITY LINES OF YBa2Cu3Oy SUPERCONDUCTOR BY MELT-TEXTURED GROWTH METHOD

1990 ◽  
Vol 04 (20) ◽  
pp. 1295-1299 ◽  
Author(s):  
C.D. WEI ◽  
Y.D. DAI ◽  
Z.X. LIU ◽  
J. LAN ◽  
H.T. REN ◽  
...  
Keyword(s):  
Activation Energy ◽  
Critical Temperature ◽  
Single Crystal ◽  
Thermal Activation ◽  
Thermal Activation Energy ◽  
Irreversibility Line ◽  
Growth Method ◽  
Order Of Magnitude ◽  
Irreversibility Lines

The study of magnetization irreversibility line of a YBaCuO superconductor fabricated by melt-textured growth method with a critical temperature Tc of 89.3 K is presented. The sample exhibits obvious anisotropy similar to the behavior of single crystal. The thermal activation energy is an order of magnitude larger than that of YBaCuO single crystal and is also larger than that of polycrystal YBaCuO sample.

DISSIPATION OF THE Bi2.4-xPbxSr2CaCu2O8+y INTRINSIC ARRAY JOSEPHSON JUNCTIONS

2005 ◽  
Vol 19 (01n03) ◽  
pp. 479-481
Author(s):  
Y. NIE ◽  
Z. H. WANG ◽  
L. QIU ◽  
S. Y. DING ◽  
J. GAO
Keyword(s):  
Activation Energy ◽  
Magnetic Fields ◽  
Temperature Dependence ◽  
Single Crystals ◽  
Field Dependence ◽  
Doping Level ◽  
Josephson Junctions ◽  
Irreversibility Line ◽  
Out Of Plane

We have fabricated a small-sized mesa on the surface of the Bi 2.4-x Pb x Sr 2 CaCu 2 O 8+y single crystals and measured the temperature dependence of the out-of-plane resistivity in different magnetic fields. The irreversibility line H irr( T ) follows different law in different temperature regions. But as a whole, the higher doping level x is, the irreversibility line locates in a higher field. The field dependence of activation energy follows U eff∝ H -m, m increases when doping level x improves.

Alkoxide Doping of GaAs During Organometallic Vapor Phase Epitaxy

1992 ◽  
Vol 282 ◽  
Author(s):  
Y. Park ◽  
M. Skowronski ◽  
T. M. Rosseel
Keyword(s):  
Activation Energy ◽  
Band Gap ◽  
Oxygen Content ◽  
Vapor Phase ◽  
Growth Temperature ◽  
Deep Level ◽  
Vapor Phase Epitaxy ◽  
Photoluminescence Intensity ◽  
Organometallic Vapor Phase Epitaxy ◽  
Fully Depleted

ABSTRACTDoping of GaAs with dimethylaluminum methoxide and its effects have been studied during metalorganic vapor phase epitaxy. Oxygen concentration decreases exponentially with increasing growth temperature and the activation energy equal to 1.8 eV.Increase of oxygen content with decrease of V/III ratio indicates that oxygen most likely occupies arsenic site. Photoluminescence intensity was observed to decrease with increasing oxygen contentand three new deep level luminescence peaks appeared at 75, 96, and 160 meV below the band gap. This, together with the fact that as-grown layers are fully depleted, indicates that oxygen is electrically active in OMVPE GaAs and forms deep non-radiative recombinationcenters.

On the Contribution of a Nitrogen-Related Defect in the Nexafs Spectra of Thin Si3N4 Films

1992 ◽  
Vol 284 ◽  
Author(s):  
E. C. Paloura ◽  
A. Knop ◽  
U. Dobler ◽  
K. Holldack ◽  
S. Logothetidis
Keyword(s):  
Activation Energy ◽  
Fine Structure ◽  
Growth Temperature ◽  
Resonance Line ◽  
Bond Formation ◽  
Annealing Process ◽  
X Ray ◽  
Strong Resonance ◽  
Related Defect ◽  
X Ray Absorption

ABSTRACTThin amorphous SiN films grown on Si are studied with Near Edge X-Ray Absorption Fine Structure (NEXAFS). The NEXAFS spectra of N-rich films are characterized by a strong resonance line (RL) at the onset of the N K- edge. The intensity of the RL in N-rich films increases with the N/Si ratio, while the same RL is detected in the NEXAFS spectra of stoichiometric SiN films subjected to damage with Ar+ ion bombardment. The RL is attributed to a N-related defect which is strongly localized in a pure 2p orbital. The RL, which is identified as a bulk nitride property, can be annealed out at temperatures higher than the growth temperature. It is proposed that the annealing process of the RL, which is characterized by an activation energy of 0.87eV, is due to Si-N bond formation, where the Si atoms are provided by the stressed SiN/Si interface.

Structure and Orientation of As Precipitates in LT-MBE Grown GaAs

1991 ◽  
Vol 49 ◽  
pp. 900-901 ◽  
Author(s):  
Alain Claverie ◽  
Zuzanna Liliental-Weber
Keyword(s):  
Transport Properties ◽  
Layer Thickness ◽  
Growth Temperature ◽  
Low Temperatures ◽  
Lattice Parameter ◽  
Crystalline Quality ◽  
Insulating Properties ◽  
Lt Gaas

GaAs layers grown by MBE at low temperatures (in the 200°C range, LT-GaAs) have been reported to have very interesting electronic and transport properties. Previous studies have shown that, before annealing, the crystalline quality of the layers is related to the growth temperature. Lowering the temperature or increasing the layer thickness generally results in some columnar polycrystalline growth. For the best “temperature-thickness” combinations, the layers may be very As rich (up to 1.25%) resulting in an up to 0.15% increase of the lattice parameter, consistent with the excess As. Only after annealing are the technologically important semi-insulating properties of these layers observed. When annealed in As atmosphere at about 600°C a decrease of the lattice parameter to the substrate value is observed. TEM studies show formation of precipitates which are supposed to be As related since the average As concentration remains almost unchanged upon annealing.

Semi-empirical calculation of activation energy for a number of bimolecular reactions. Part I

1971 ◽  
Vol 68 ◽  
pp. 753-757 ◽  
Author(s):  
M.B. Pahari ◽  
Rama Basu
Keyword(s):  
Activation Energy ◽  
Bimolecular Reactions ◽  
Semi Empirical
Sign in / Sign up

Export Citation Format

Share Document