Observations on a high temperature peak in the thermoluminescence of fluorites

Pramana ◽  
1980 ◽  
Vol 14 (2) ◽  
pp. 165-173 ◽  
Author(s):  
M A El-Kolaly ◽  
S M D Rao ◽  
K S V Nambi ◽  
A K Ganguly
Keyword(s):  
High Temperature ◽  
Temperature Peak ◽  
High Temperature Peak

Early-life temperature modifies adult encapsulation response in an invasive ectoparasite

Parasitology ◽  
2015 ◽  
Vol 142 (10) ◽  
pp. 1290-1296 ◽  
Author(s):  
SIRPA KAUNISTO ◽  
LAURA HÄRKÖNEN ◽  
MARKUS J. RANTALA ◽  
RAINE KORTET
Keyword(s):  
Climate Change ◽  
High Temperature ◽  
Low Temperature ◽  
Blood Feeding ◽  
Life Cycles ◽  
Extreme Weather Events ◽  
Favourable Effect ◽  
Temperature Peak ◽  
Long Term Effects ◽  
High Temperature Peak

SUMMARYImmunity of parasites has been studied amazingly little, in spite of the fact that parasitic organisms, especially the arthropod parasites, need immunity to survive their own infections to successfully complete life cycles. Long-term effects of challenging environmental temperatures on immunity have remained unstudied in insects and parasites. Our study species, the deer ked (Lipoptena cervi; Linnaeus 1758), is an invasive, blood-feeding parasitic fly of cervids. Here, it was studied whether thermal stress during the pupal diapause stage could modify adult immunity (encapsulation capacity) in L. cervi. The effect of either a low temperature or high temperature peak, experienced during winter dormancy, on encapsulation response of active adult was tested. It was found that low temperature exposure during diapause, as long as the temperature is not too harsh, had a favourable effect on adult immunity. An abnormal, high temperature peak during pupal winter diapause significantly deteriorated the encapsulation capacity of emerged adults. The frequency and intensity of extreme weather events such as high temperature fluctuations are likely to increase with climate change. Thus, the climate change might have previously unknown influence on host-ectoparasite interactions, by affecting ectoparasite's immune defence and survival.

scholarly journals Thermal Properties and Structural Features of Multilayer Films Based on Chitosan and Anionic Polysaccharides

Biomolecules ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 762
Author(s):  
Galina N. Gubanova ◽  
Valentina A. Petrova ◽  
Svetlana V. Kononova ◽  
Elena N. Popova ◽  
Valentina E. Smirnova ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
Glass Transition ◽  
Thermal Properties ◽  
High Temperature ◽  
Dynamic Mechanical Analysis ◽  
Mechanical Analysis ◽  
Temperature Peak ◽  
High Temperature Peak ◽  
Dynamic Mechanical ◽  
Multilayer Composites

This study investigates the thermal and structural properties of multilayer composites based on chitosan (CS) and polyanions with different functionalities, including sodium sulfoethyl cellulose (SEC), sodium alginate (ALG), and sodium hyaluronate (HA). Unlike polyelectrolyte complexes (PECs) obtained by polymer mixing, the formation of a PEC layer by a process of layer-by-layer deposition of oppositely charged polymers is accompanied by the transformation of the CS polymorphic state, and this affects the relaxation and thermal properties of the resulting multilayer composite. X-ray diffraction analysis showed that the formation of the PEC layer in the CS/SEC multilayer film is accompanied by crystallization of the CS chains and the formation of a predominantly anhydrous CS modification. Thermogravimetric analysis of the CS/SEC film registers a high-temperature peak associated with the thermal decomposition of crystalline CS in the PEC composition. According to the dynamic mechanical analysis, the CS/SEC composite was characterized by a single glass transition temperature, indicating a strong interaction between the layers when using SEC (a strong acid salt) as the counterion to CS. For multilayer composites with weak polyacid salts (ALG and HA), the crystallization of CS in the PEC layer is weaker, as reflected in the thermal degradation of these films. A high-temperature peak is recorded in the thermal decomposition of CS/HA and is absent in the case of CS/ALG. Dynamic mechanical analysis of the CS/ALG composite showed two glass transition temperatures close to those of the original polymers, indicating weak PEC formation. The CS/HA composite showed an intermediate response. Thus, the effect of the PEC layer on the properties of the poly-layer composites decreases in the order CS/SEC > CS/HA > CS/ALG.

The high temperature peak of the yield strength of γ′-strengthened superalloys

2006 ◽  
Vol 429 (1-2) ◽  
pp. 277-286 ◽  
Author(s):  
Eckhard Nembach
Keyword(s):  
High Temperature ◽  
Yield Strength ◽  
Temperature Peak ◽  
High Temperature Peak

Recrystallization and Grain Boundary Formation in an 18-Carat Gold Alloy Studied by Mechanical Spectroscopy

2013 ◽  
Vol 753 ◽  
pp. 17-20 ◽  
Author(s):  
Ann Kathrin Maier ◽  
Iva Tkalcec ◽  
Daniele Mari ◽  
Robert Schaller
Keyword(s):  
Grain Size ◽  
High Temperature ◽  
Relaxation Mechanism ◽  
Peak Position ◽  
Temperature Peak ◽  
Mechanical Spectroscopy ◽  
Mechanical Loss ◽  
Carat Gold ◽  
High Temperature Peak ◽  
Mean Grain Size

Heavily deformed 18-carat yellow gold samples show a recrystallization peak at 700 K during the first heating. The mechanical loss spectrum of polycrystals shows a relaxation peak at about 780 K, which is absent in single crystals made from the same alloy. Stepwise deformation of a single crystal from 2 % to 10 % causes an increase of the high temperature mechanical loss background and the appearance of a high temperature peak. At 8 % deformation the high temperature peak disappears and the peak that is normally observed in polycrystals appears. The increase of the exponential background is interpreted as due to the introduction of new dislocations whereas the high temperature peak is attributed to a relaxation mechanism in the sub grain boundaries. The peak of polycrystalline samples located at intermediate temperatures depends on the grain size: with grain growth, the peak position shifts to higher temperatures. The peak temperature can be related to the mean grain size.

Non-linearity of the high temperature peak area ratio of 6LiF:Mg,Ti (TLD-600)

2000 ◽  
Vol 32 (4) ◽  
pp. 355-360 ◽  
Author(s):  
H. Yasuda ◽  
K. Fujitaka
Keyword(s):  
High Temperature ◽  
Area Ratio ◽  
Temperature Peak ◽  
High Temperature Peak ◽  
Peak Area Ratio

THERMAL DECOMPOSITION REACTIONS OF CLAY–ORGANIC MATTER COMPLEXES AND ORGANIC MATTER SEPARATED FROM A BLACK CHERNOZEMIC SOIL

1972 ◽  
Vol 52 (3) ◽  
pp. 417-425 ◽  
Author(s):  
L. E. LUTWICK
Keyword(s):  
Thermal Decomposition ◽  
Organic Matter ◽  
High Temperature ◽  
Temperature Peak ◽  
Ultrasonic Dispersion ◽  
High Temperature Peak ◽  
Chernozemic Soil ◽  
Decomposition Reactions

Clay–organic matter complexes (< 2 μ) were separated in four serial extracts through ultrasonic dispersion from a Black Chernozemic soil developed on calcareous till. Derivative thermograms (DTG) of the complexes were similar to those of organic matter extracted from the same soil with alkali. The thermograms of the easily extracted materials (first two extracts) did not have a high temperature peak unless the materials were treated with acid. The thermograms of the difficult to extract materials and of the coarser residual materials (silts and roots) did have a high temperature peak.

Search for High Damping Metallic Glasses

2006 ◽  
Vol 319 ◽  
pp. 151-156 ◽  
Author(s):  
Y. Hiki ◽  
M. Tanahashi ◽  
Shin Takeuchi
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Internal Friction ◽  
Metallic Glass ◽  
Room Temperature ◽  
Temperature Stability ◽  
Temperature Peak ◽  
High Temperature Side ◽  
Side Slope ◽  
Temperature Side

In a hydrogen-doped metallic glass, there appear low-temperature and high-temperature internal friction peaks respectively associated with a point-defect relaxation and the crystallization. The high-temperature-side slope of low-temperature peak and also the low-temperature-side slope of high-temperature peak enhance the background internal friction near the room temperature. A hydrogen-doped Mg-base metallic glass was proposed as a high-damping material to be used near and somewhat above the room temperature. Stability of the high damping was also checked.

Design and fabrication of a power Si/SiC LDMOSFET for high temperature applications

2017 ◽  
Vol 2017 (HiTEN) ◽  
pp. 000219-000222
Author(s):  
F. Li ◽  
P.M. Gammon ◽  
C.W. Chan ◽  
F. Gity ◽  
T. Trajkovic ◽  
...  
Keyword(s):  
High Temperature ◽  
High Voltage ◽  
Field Effect ◽  
Room Temperature ◽  
Harsh Environment ◽  
Avalanche Breakdown ◽  
Temperature Peak ◽  
Channel Mobility ◽  
First Time ◽  
Peak Field

Abstract Power Si/SiC LDMOSFET are being developed for the benefits of high temperature space and terrestrial harsh-environment applications. For the first time, high voltage devices are fabricated on a direct bonded Si/SiC substrate and characterised at room temperature. Peak field-effect channel mobility of the fabricated MOSFET reached ≈300 cm2/V.s and the avalanche breakdown was not observed up to 200 V, despite of a high leakage current in the device off-mode.

Thermally Stimulated Conductivity in a-Si:H at low Temperatures

1994 ◽  
Vol 336 ◽  
Author(s):  
M. Zhu ◽  
M.B. Von Der Linden ◽  
W.F. Van Der Weg
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Low Temperatures ◽  
Thermal Emission ◽  
Temperature Peak ◽  
Band Tail ◽  
Emission Energy ◽  
Temperature Range ◽  
Multiple Trapping ◽  
Peak Value

ABSTRACTThe low temperature thermally stimulated conductivity (TSC) in a-Si:H film has been investigated in the temperature range from 20 to 150 K. Unlike the results of the high temperature TSC, the low temperature peak value and position (Tm) of TSC do not depend on the starting temperature T0 at low temperatures. This new phenomenon can not be explained by TSC theory [1]. Based on the multiple trapping (MT) Model, TSC theory limits its application to the intermediate and high temperature range. In this paper, a model of the hopping conduction with the transport energy Et in the band tail is proposed to understand the behavior of the low temperature TSC in which the thermal emission energy Em does not depend on the starting temperature of TSC.

H Evolution from Nano-Crystalline Silicon- Comparison of Simulation and Experiment

2004 ◽  
Vol 808 ◽  
Author(s):  
R. Biswas ◽  
B. C. Pan
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Crystalline Silicon ◽  
Nanocrystalline Silicon ◽  
Temperature Peak ◽  
Nano Crystalline ◽  
Crystallite Surface ◽  
Excess Density ◽  
Simulation And Experiment ◽  
Higher Temperature

ABSTRACTThe temperature dependent H evolution from a-Si:H provides unique information on the H-bonding and microstructure. Traditional undiluted a-Si:H films show a high temperature H-evolution peak near 600°C. However device-quality compact nanocrystalline silicon films grown near the phase boundary of amorphous and microcrystalline growth show a new low temperature H- evolution peak near 400°C in addition to a second high temperature peak near 600°C. The origin of this peak cannot be attributed to microvoids or a substantial density of dihydride species typical of porous low-temperature films. We have simulated the H evolution using a molecular dynamics generated model of nanocrystalline silicon, where nano-crystallites reside in a background amorphous matrix. An excess density of H occurs at the crystallite surface. We find a low temperature evolution peak at 250-400°C, where the H-evolution starts from the surface of the nano-crystallite. In addition there is a higher temperature peak at 700-800°C providing good agreement with H-evolution measurements. The mobile H is found to exist in both the bond-centered type of species and H2 molecules – which has implications for H-diffusion models.

Sign in / Sign up

Export Citation Format

Share Document