scholarly journals Design and fabrication of sintered Nd-Fe-B magnets with a low temperature coefficient of intrinsic coercivity

2009 ◽  
Vol 41 (1) ◽  
pp. 91-99 ◽  
Author(s):  
X.G. Cui ◽  
M. Yan ◽  
T.Y. Ma ◽  
W. Luo ◽  
S.J. Tu

To decrease the temperature coefficients of sintered Nd-Fe-B magnets, the influencing factors on temperature coefficients, especially the reversible temperature coefficient ? of intrinsic coercivity Hcj, were analyzed. The results showed that the absolute value of ? decreased with increasing Hcj and also the ratio of microstructure parameter c to Neff, indicating that the increase of magnetocrystalline anisotropy field HA and c/Neff can effectively decrease the absolute value of ?. On the basis of this analysis, a sintered Nd-Fe-B magnet with a low temperature coefficient of Hcj was fabricated through composition design, and the value of ? was only -0.385%/?C in the temperature interval of 20-150?C.

1973 ◽  
Vol 51 (18) ◽  
pp. 3152-3155 ◽  
Author(s):  
Huw O. Pritchard

It is shown that previously calculated nonequilibrium rate constants for the dissociation of H2 and D2 appear to approach a rotationally averaged equilibrium expression at low temperature. This equilibrium form of the rate expression itself has an Arrhenius temperature coefficient for dissociation which is significantly less than the dissociation energy, and the corresponding recombination rate constant has a negative temperature coefficient. The reasons for this are explained.


2010 ◽  
Vol 43 ◽  
pp. 371-375 ◽  
Author(s):  
Quan Wang ◽  
Jin Zhang ◽  
Ran Hu ◽  
Guo Qiang Sun

This paper presents the principles of the transistor compensation technology of temperature coefficient of sensitivity (TCS) of pressure sensor. A quantitative compensation formula is demonstrated in mathematics. By experiments, the absolute value of the compensated TCS is easy to be 10×10-6/°C~100 ×10-6/°C with individual adjustment and calibration of each device’s temperature compensation. The feasibility and practicability of this technology are tested. The disadvantages are discussed after the research of the experimental data, while the improvement methods are also given in the designing period. This technology exhibits the great potential practical value. These applications are promoted in the volume production. The operating performances of these pressure sensors using this technology are studied and proved they are reliable and stable.


Author(s):  
P. Echlin ◽  
M. McKoon ◽  
E.S. Taylor ◽  
C.E. Thomas ◽  
K.L. Maloney ◽  
...  

Although sections of frozen salt solutions have been used as standards for x-ray microanalysis, such solutions are less useful when analysed in the bulk form. They are poor thermal and electrical conductors and severe phase separation occurs during the cooling process. Following a suggestion by Whitecross et al we have made up a series of salt solutions containing a small amount of graphite to improve the sample conductivity. In addition, we have incorporated a polymer to ensure the formation of microcrystalline ice and a consequent homogenity of salt dispersion within the frozen matrix. The mixtures have been used to standardize the analytical procedures applied to frozen hydrated bulk specimens based on the peak/background analytical method and to measure the absolute concentration of elements in developing roots.


Alloy Digest ◽  
1960 ◽  
Vol 9 (4) ◽  

Abstract EVANOHM is a nickel-base alloy having low temperature coefficient of resistance and high electrical resistivity. This datasheet provides information on composition, physical properties, hardness, and tensile properties. It also includes information on joining. Filing Code: Ni-57. Producer or source: Wilbur B. Driver Company.


Alloy Digest ◽  
1957 ◽  
Vol 6 (8) ◽  

Abstract ISO-ELASTIC is an iron-nickel alloy having low temperature coefficient of the modulus of elasticity. It is suitable for precision instrument springs. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, and machining. Filing Code: Fe-14. Producer or source: John Chatillon & Sons.


2020 ◽  
Vol 11 (1) ◽  
pp. 20
Author(s):  
Muhammad Ikbal Abdullah ◽  
Andi Chairil Furqan ◽  
Nina Yusnita Yamin ◽  
Fahri Eka Oktora

This study aims to analyze the sensitivity testing using measurements of realization of regional own-source revenues and operating expenditure and to analyze the extent of the effect of sample differences between Java and non-Java provinces by using samples outside of Java. By using sensitivity analysis, the results found the influence of audit opinion on the performance of the provincial government mediated by the realization of regional operating expenditure. More specifically, when using the measurement of the absolute value of the realization of regional operating expenditure it was found that there was a direct positive and significant influence of audit opinion on the performance of the Provincial Government. However, no significant effect of audit opinion was found on the realization value of regional operating expenditure and the effect of the realization value of regional operating expenditure on the performance of the Provincial Government. This result implies that an increase in audit opinion will be more likely to be used as an incentive for the Provincial Government to increase the realization of regional operating expenditure.


1977 ◽  
Vol 32 (11-12) ◽  
pp. 908-912 ◽  
Author(s):  
H. J. Schmidt ◽  
U. Schaum ◽  
J. P. Pichotka

Abstract The influence of five different methods of homogenisation (1. The method according to Potter and Elvehjem, 2. A modification of this method called Potter S, 3. The method of Dounce, 4. Homogenisation by hypersonic waves and 5. Coarce-grained homogenisation with the “Mikro-fleischwolf”) on the absolute value and stability of oxygen uptake of guinea pig liver homogenates has been investigated in simultaneous measurements. All homogenates showed a characteristic fall of oxygen uptake during measuring time (3 hours). The modified method according to Potter and Elvehjem called Potter S showed reproducible results without any influence by homogenisation intensity.


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