High-temperature spectra of the pure rotational band of H2O

1965 ◽  
Vol 5 (5) ◽  
pp. 697-714 ◽  
Author(s):  
C.B. Ludwig ◽  
C.C. Ferriso ◽  
W. Malkmus ◽  
F.P. Boynton
Keyword(s):  
High Temperature ◽  
Rotational Band ◽  
Temperature Spectra

The Microscopic Structure Of Shallow Donors In Silicon Carbide

1996 ◽  
Vol 442 ◽  
Author(s):  
J.-M. Spaeth ◽  
S. Greulich-Weber ◽  
M. März ◽  
E. N. Kalabukhova ◽  
S. N. Lukin
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Temperature Dependence ◽  
Double Resonance ◽  
Epr Spectra ◽  
Electron Nuclear Double Resonance ◽  
Paramagnetic Resonance ◽  
Vacancy Pair ◽  
Temperature Spectra ◽  
Electron Paramagnetic

AbstractThe electronic structure of nitrogen donors in 6H-, 4H- and 3C-SiC is investigated by measuring the nitrogen hyperfine (hf) interactions with electron nuclear double resonance (ENDOR) and the temperature dependence of the hf split electron paramagnetic resonance (EPR) spectra. Superhyperfine (shf) interactions with many shells of 13C and 29Si were measured in 6H-SiC. The hf and shf interactions are discussed in the framework of effective mass theory. The temperature dependence is explained with the thermal occupation of the lowest valley-orbit split A1 and E states. It is proposed that the EPR spectra of P donors observed previously in neutron transmuted 6H-SiC at low temperature (<10K) and high temperature (>60K) are all due to substitutional P donors on the two quasi-cubic and hexagonal Si sites, whereby at low temperature the E state is occupied and at high temperature the A1 state. The low temperature spectra are thus thought not to be due to P-vacancy pair defects as proposed previously.

Study on high-temperature spectra of asymptotic asymmetric-top radical SiO 2

2010 ◽  
Vol 19 (4) ◽  
pp. 043301 ◽  
Author(s):  
Wu Dong-Lan ◽  
Zeng Xue-Feng ◽  
Xie An-Dong ◽  
Wan Hui-Jun
Keyword(s):  
High Temperature ◽  
Temperature Spectra ◽  
Asymmetric Top

Study on High-Temperature Spectra of Asymptotic Asymmetric-Top Molecule O 3

2008 ◽  
Vol 50 (2) ◽  
pp. 481-485
Author(s):  
Song Xiao-Shu ◽  
Guo Yun-Dong ◽  
Ling-Hu Rong-Feng ◽  
Lü Bing ◽  
Cheng Xin-Lu ◽  
...  
Keyword(s):  
High Temperature ◽  
Temperature Spectra ◽  
Asymmetric Top

Microwave Spectroscopy at High Temperature-Spectra of CsCl and NaCl

1952 ◽  
Vol 86 (5) ◽  
pp. 813-814 ◽  
Author(s):  
M. L. Stitch ◽  
A. Honig ◽  
C. H. Townes
Keyword(s):  
High Temperature ◽  
Microwave Spectroscopy ◽  
Temperature Spectra

Time-resolved remote Raman study of minerals under supercritical CO 2 and high temperatures relevant to Venus exploration

2010 ◽  
Vol 368 (1922) ◽  
pp. 3167-3191 ◽  
Author(s):  
Shiv K. Sharma ◽  
Anupam K. Misra ◽  
Samuel M. Clegg ◽  
James E. Barefield ◽  
Roger C. Wiens ◽  
...  
Keyword(s):  
High Temperature ◽  
Raman Spectra ◽  
High Temperatures ◽  
Ambient Pressure ◽  
Fermi Resonance ◽  
Time Resolved ◽  
Temperature Spectra ◽  
Resonance Doublet ◽  
Partial Dissociation ◽  
Surface Mineralogy

We report time-resolved (TR) remote Raman spectra of minerals under supercritical CO 2 (approx. 95 atm pressure and 423 K) and under atmospheric pressure and high temperature up to 1003 K at distances of 1.5 and 9 m, respectively. The TR Raman spectra of hydrous and anhydrous sulphates, carbonate and silicate minerals (e.g. talc, olivine, pyroxenes and feldspars) under supercritical CO 2 (approx. 95 atm pressure and 423 K) clearly show the well-defined Raman fingerprints of each mineral along with the Fermi resonance doublet of CO 2 . Besides the CO 2 doublet and the effect of the viewing window, the main differences in the Raman spectra under Venus conditions are the phase transitions, the dehydration and decarbonation of various minerals, along with a slight shift in the peak positions and an increase in line-widths. The dehydration of melanterite (FeSO 4  · 7H 2 O) at 423 K under approximately 95 atm CO 2 is detected by the presence of the Raman fingerprints of rozenite (FeSO 4  · 4H 2 O) in the spectrum. Similarly, the high-temperature Raman spectra under ambient pressure of gypsum (CaSO 4  · 2H 2 O) and talc (Mg 3 Si 4 O 10 (OH) 2 ) indicate that gypsum dehydrates at 518 K, but talc remains stable up to 1003 K. Partial dissociation of dolomite (CaMg(CO 3 ) 2 ) is observed at 973 K. The TR remote Raman spectra of olivine, α-spodumene (LiAlSi 2 O 6 ) and clino-enstatite (MgSiO 3 ) pyroxenes and of albite (NaAlSi 3 O 8 ) and microcline (KAlSi 3 O 8 ) feldspars at high temperatures also show that the Raman lines remain sharp and well defined in the high-temperature spectra. The results of this study show that TR remote Raman spectroscopy could be a potential tool for exploring the surface mineralogy of Venus during both daytime and nighttime at short and long distances.

scholarly journals Study on high-temperature spectra of the asymptotic asymmetric-top molecule H122C16O

2008 ◽  
Vol 57 (6) ◽  
pp. 3440
Author(s):  
Song Xiao-Shu ◽  
Linghu Rong-Feng ◽  
Lü Bing ◽  
Cheng Xin-Lu ◽  
Yang Xiang-Dong
Keyword(s):  
High Temperature ◽  
Temperature Spectra ◽  
Asymmetric Top

High-temperature three-axis IRM Lowrie test

2021 ◽  
Author(s):  
Leonid Surovitskii ◽  
Andrei Kosterov ◽  
Mary Kovacheva ◽  
Maria Kostadinova-Avramova ◽  
Natalya Salnaya ◽  
...  
Keyword(s):  
High Temperature ◽  
Elevated Temperatures ◽  
Basic Research ◽  
Archaeological Sites ◽  
High Coercivity ◽  
Variable Degree ◽  
Hard Component ◽  
Classical Procedure ◽  
Temperature Spectra ◽  
Basic Research Grant

&lt;p&gt;The three-axis isothermal remanent magnetization (IRM) test (the Lowrie test; Lowrie, 1990, Geophys. Res. Lett., 17, 159-162) is a useful tool to identify ferromagnetic minerals by their coercivity and unblocking temperature spectra. In this study, we explore a variant of the Lowrie test in which measurements are conducted directly at elevated temperatures, and compare its performance with the results of the conventional stepwise procedure. IRM acquisition fields&amp;#160;applied along three orthogonal axes were 1 T, 200 mT and 40 mT, respectively. The field value for the soft component was chosen so as to include&amp;#160;ca. 90% of its coercivity spectrum. For the hard component the maximum available field was used. The test is applied to characterize the magnetic mineralogy of archaeological baked clays and bricks from Bulgaria and Russia. Bulgarian samples are baked clays from various Neolithic (5700-5300 BCE) archaeological sites and several bricks of the Roman epoch (III-IV c. AD). Samples from Russia are bricks originating from several regions with ages from XIII to early XIX c. AD.&lt;/p&gt;&lt;p&gt;The low- and intermediate-coercivity components of IRM in the studied samples are typically demagnetized by 520-550&amp;#176;C, compatible with substituted or cation-deficient magnetite or, possibly, maghemite. This is supported by the absence of the Verwey transition in studied samples (Kosterov et al., 2021, Geophys. J. Int., 224(2), 1256-1271). The high-coercivity component appears to be carried by two mineral phases with very distinct unblocking temperatures, 120-200&amp;#176;C and 500 to 640&amp;#176;C. The first phase is similar to the high coercivity, low unblocking temperature (HCSLT) phase described by McIntosh et al., 2007 (Geophys. Res. Lett., 34, L21302, doi: 10.1029/22007GL031168), and the second one appears to be hematite with variable degree of substitution.&lt;/p&gt;&lt;p&gt;Performance of the high-temperature variant of the Lowrie test compares favorably with the classical procedure, while the former is also significantly faster and yields a superior temperature resolution.&lt;/p&gt;&lt;p&gt;This study is supported by Russian Foundation of the Basic Research, grant 19-55-18006, and by Bulgarian National Science Fund, grant KP-06-Russia-10.&lt;/p&gt;

Influence of Thermo-Mechanical Processing on the Microstructure of Beryllia Dispersed Nickel Alloys

1973 ◽  
Vol 31 ◽  
pp. 184-185
Author(s):  
M.S. Grewal ◽  
S.A. Sastri ◽  
N.J. Grant
Keyword(s):  
High Temperature ◽  
Nickel Alloys ◽  
Thermomechanical Processing ◽  
Cold Work ◽  
High Temperature Strength ◽  
Strengthening Effect ◽  
Mechanical Processing ◽  
Uniform Dispersion ◽  
Oxide Particles ◽  
Nickel Base

Currently there is a great interest in developing nickel base alloys with fine and uniform dispersion of stable oxide particles, for high temperature applications. It is well known that the high temperature strength and stability of an oxide dispersed alloy can be greatly improved by appropriate thermomechanical processing, but the mechanism of this strengthening effect is not well understood. This investigation was undertaken to study the dislocation substructures formed in beryllia dispersed nickel alloys as a function of cold work both with and without intermediate anneals. Two alloys, one Ni-lv/oBeo and other Ni-4.5Mo-30Co-2v/oBeo were investigated. The influence of the substructures produced by Thermo-Mechanical Processing (TMP) on the high temperature creep properties of these alloys was also evaluated.

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