High temperature ferromagnetism in NbCo2 nanoparticles – Bulk magnetization and hyperfine field measurements

<p>Calibration of thermal imaging system is not a straight forward process and hence manufacturers suggest re-calibration at factory itself. However, it is time consuming and expensive. A few research papers refer various approaches to perform low temperature calibration considering the wide requirement of low temperature measurements (typically less than 150 °C). However, no reference is available in open literature about high temperature calibration of thermal imagers. Hence, the possibility of high temperature calibration of thermal imaging systems has been explored using high temperature blackbody sources available at laboratory. With the use of neutral density filters, calibration has been performed in mid-wave (3.7 μm - 4.8 μm) and long-wave (7.7 μm - 9.5 μm) bands of imagers for IR measurements. The developed calibration has also been tested for field measurements.</p>

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Structure and Magnetic Properties of Aerosol Nanoparticles of Fe and Its Alloys

International Journal of Inorganic Chemistry ◽

10.1155/2012/610305 ◽

2012 ◽

Vol 2012 ◽

pp. 1-43 ◽

Cited By ~ 3

Author(s):

Yu. I. Petrov ◽

E. A. Shafranovsky

Keyword(s):

Magnetic Properties ◽

Fine Structure ◽

High Temperature ◽

Hyperfine Field ◽

Field Distribution ◽

Pure Iron ◽

Bulk Material ◽

Magnetic Interactions ◽

Hyperfine Field Distribution ◽

Aerosol Nanoparticles

Structure and magnetic properties of aerosol nanoparticles of Fe and its alloys (FeMn, FeNi, FeNiMn, FePt, FeCr, FeCo, and FeCu) have been reviewed. It has been shown that, compared to a bulk material, the particles have a number of specific features being of much fundamental and applied interest. The effect of both a quenched high-temperature Fe modification and its oxides on the structure and magnetism of nanoparticles has been considered in detail. Particular attention has been paid to the recently observed fine structure in the hyperfine field distribution at iron nuclei in Mössbauer spectra for pure iron and its alloys both as a bulk and aerosol nanoparticles. This phenomenon makes it possible to reveal very weak magnetic interactions in the system under study. The plausible origin of these magnetic interactions has been also discussed.

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Hyperfine-Field Measurements on Sc in Fe and Re in Ni

Physical Review B ◽

10.1103/physrevb.7.2942 ◽

1973 ◽

Vol 7 (7) ◽

pp. 2942-2947 ◽

Cited By ~ 6

Author(s):

D. K. Gupta ◽

A. K. Singhvi ◽

D. N. Sanwal ◽

G. N. Rao

Keyword(s):

Hyperfine Field ◽

Field Measurements

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Hyperfine field measurements on dilute scandium in cobalt matrix

Physics Letters A ◽

10.1016/0375-9601(74)90184-4 ◽

1974 ◽

Vol 47 (4) ◽

pp. 319-320 ◽

Cited By ~ 1

Author(s):

A.K. Singhvi ◽

G.N. Rao

Keyword(s):

Hyperfine Field ◽

Field Measurements

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High-temperature high-frequency turbine exit flow field measurements in a military engine with a cooled unsteady total pressure probe

Proceedings of the Institution of Mechanical Engineers Part A Journal of Power and Energy ◽

10.1177/0957650911413697 ◽

2011 ◽

Vol 225 (7) ◽

pp. 954-963 ◽

Cited By ~ 3

Author(s):

M Mersinligil ◽

J Desset ◽

J F Brouckaert

Keyword(s):

High Temperature ◽

Total Pressure ◽

Pressure Sensors ◽

Field Measurements ◽

Fast Response ◽

Turbine Engines ◽

Pressure Probe ◽

Gas Turbine Engines ◽

Time Resolved ◽

High Bandwidth

The measurement of unsteady pressures within the hot components of gas turbine engines still remains a true challenge for test engineers. Several high-temperature pressure sensors have been developed, but so far, their applications are restricted to unsteady wall static pressure measurements. Because of the severe flow conditions such as turbine inlet temperatures of 1700 °C and pressures of 50 bar or more in the most advanced aero-engine designs, few (if any) experimental techniques exist to measure the time-resolved flow total pressure inside the gas path. This article describes the measurements performed at the turbine exit of a military engine with a cooled fast response total pressure probe. The probe concept is based on the use of a conventional miniature piezo-resistive pressure sensor, located in the probe tip to achieve a bandwidth of at least 40 kHz. Due to the extremely harsh conditions, the probe and sensor are heavily water cooled. The probe was designed to be continuously immersed into the hot gas stream to obtain time series of pressure with a high bandwidth and therefore statistically representative average fluctuations at the blade passing frequency (BPV). The experimental results obtained with a second-generation prototype are presented. The probe was immersed into the engine through the bypass duct between turbine exit and flame-holders of the afterburner of a Volvo RM12 engine, at exhaust temperatures above 900 °C. The probe was able to resolve the BPV (∼17 kHz) and several harmonics up to 100 kHz.

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Transient hyperfine field measurements of gyromagnetic ratios in Os and Pt nuclei

Physical Review C ◽

10.1103/physrevc.27.434 ◽

1983 ◽

Vol 27 (1) ◽

pp. 434-437 ◽

Cited By ~ 7

Author(s):

A. E. Stuchbery ◽

C. G. Ryan ◽

H. Ohnuma ◽

G. B. Beard ◽

H. H. Bolotin

Keyword(s):

Hyperfine Field ◽

Field Measurements

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