scholarly journals Saturation magnetostriction and its low-temperature variation inferred for natural titanomaghemites: implications for internal stress control of coercivity in oceanic basalts

2004 ◽  
Vol 157 (3) ◽  
pp. 1017-1026 ◽  
Author(s):  
J. P. Hodych ◽  
J. Matzka
2005 ◽  
Vol 62 (6) ◽  
pp. 543-546 ◽  
Author(s):  
Rafael José Navas da Silva ◽  
Eduardo Rossini Guimarães ◽  
José Francisco Garcia ◽  
Paulo Sérgio Machado Botelho ◽  
Maria Inês Tiraboschi Ferro ◽  
...  

The increased rate of sugarcane harvest without previous burn has provided a very favorable environment to the froghopper Mahanarva fimbriolata (Stal, 1854), with high moisture and low temperature variation. Few works have studied the response of sugarcane to this pest, so little is known about resistant cultivars. Plant phenolics are widely studied compounds because of their known antiherbivore effect. This research aims to determine if the attack of M. fimbriolata nymphs stimulates the accumulation of total phenolics in sugarcane. The experiment was carried out in greenhouse and arranged in completely randomized design, in a 3 X 2 X 4 factorial with three replications. Second instar nymphs of M. fimbriolata were infested at the following rates: control, 2-4 and 4-8 nymphs per pot (first-second infestations, respectively). Pots were covered with nylon net and monitored daily to isolate the effect of leaf sucking adults. Leaf and root samples were collected and kept frozen in liquid nitrogen until analyses. Infested plants showed higher levels of phenolics in both root and leaf tissues. In roots, the cultivar SP80-1816 accumulated more phenolic compounds in response to the infestation of M. fimbriolata. On the other hand, higher levels were found in leaves and roots of control plants of SP86-42, which might be an indication of a non-preference mechanism. The increase of total phenolics in sugarcane infested with root-sucking froghopper nymphs does not seem to be useful to detect the resistance to this pest.


2018 ◽  
Vol 2018.67 (0) ◽  
pp. 221
Author(s):  
Ryuji ISHIKI ◽  
Shohei UEJIMA ◽  
Mizue MIZOSHIRI ◽  
Junpei SAKURAI ◽  
Seiichi HATA

2014 ◽  
Vol 32 (4) ◽  
pp. 626-632 ◽  
Author(s):  
Pramod Yadawa

AbstractHigher order elastic constants have been calculated in hexagonally structured superionic conductor Li3N at room temperature using the interaction potential model. The temperature variation of the ultrasonic velocities was evaluated along different angles with z axis (unique axis) of the crystal, using the second order elastic constants. The ultrasonic velocity decreased with the temperature along a particular orientation of the unique axis. Temperature variation of the thermal relaxation time and Debye average velocities was also calculated along the same orientation. The temperature dependency of ultrasonic properties was discussed in correlation with elastic, thermal and electrical properties. It has been found that the thermal conductivity is the main contributor to the behavior of ultrasonic attenuation as a function of temperature and the cause responsible for attenuation is phonon-phonon interaction. The mechanical properties of Li3N at low temperature are better than at high temperature because at low temperature it has low ultrasonic attenuation. Superionic conductor lithium nitride has many industrial applications, such as those used in portable electronic devices.


2006 ◽  
Vol 517 ◽  
pp. 141-146
Author(s):  
Tarriq Munir ◽  
Azlan Abdul Aziz ◽  
Mat Johar Abdullah ◽  
Naser Mahmoud Ahmed

We focus in this paper the temperature variation effects on the current – voltage ( I-V) characteristics of n-GaN schottky diode. The diode was doped with carrier concentration 1*1013cm-3 and Pt electrode was used. The simulated current were obtained at temperatures from 50K to 500K and voltage up to 2Volt. We use the Srh (Schokley read hall), Cvt (Lombardi Model), Auger (Auger), Fermi (Fermi Dirac), Impact, Bgn (Bandgap Narrowing), Complete ioniz model to get the schottky rectifying current – voltage (I-V) characteristics.. We find that by increasing the temperature from 50K to 500K, the forward schottky rectifying current decreases from 2.7187 Amp to 0.383 Amp. while the forward turn – on voltage decreases. In reverse bias at low temperature the current is high and we increase the temperature the current decreases. The breakdown voltage decreases at higher temperature.


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