scholarly journals UNIVERSAL RELATIONSHIP BETWEEN MAGNETIZATION AND CHANGES IN THE LOCAL STRUCTURE IN QUASICUBIC AND BILAYER MANGANITES

2005 ◽  
Vol 19 (01n03) ◽  
pp. 529-532
Author(s):  
FRANK BRIDGES ◽  
LISA DOWNWARD ◽  
J. J. NEUMEIER ◽  
J. MITCHELL ◽  
HONG ZHENG
Keyword(s):  
Magnetic Field ◽  
Local Structure ◽  
Pair Distribution Function ◽  
Magnetization Process ◽  
Local Distortion ◽  
Universal Relationship ◽  
Polaron Formation ◽  
Significant Change ◽  
The Relationship ◽  
Local Distortions

We extend our previous EXAFS investigations on the relationship between magnetization and local distortions to the bilayer materials La 2-2x Sr 1+2x Mn 2 O 7 and to higher magnetic fields, for quasicubic La 0.7 Ca 0.3 MnO 3. For each, there is a significant change in the broadening parameter σ of the Mn-O pair distribution function (PDF) associated with polaron formation as T is increased through T c. Applying a magnetic field reduces the local distortion of the Ca sample for temperatures near T c. For samples with sharp transitions, there is still a significant change of σ2 with T below T c when the sample is fully magnetized, i.e. distortions are still present and continuing to be removed as T is lowered well below T c. A simple model is presented for the magnetization process.

Evidence for a Universal Relationship Between Magnetization and Changes in the Local Structure

2003 ◽  
Vol 17 (18n20) ◽  
pp. 3726-3728 ◽  
Author(s):  
L. Downward ◽  
F. Bridges ◽  
D. Cao ◽  
J. Neumeier ◽  
L. Zhou
Keyword(s):  
Magnetic Field ◽  
Distribution Function ◽  
Local Structure ◽  
Pair Distribution Function ◽  
Colossal Magnetoresistance ◽  
X Ray ◽  
Polaron State ◽  
Universal Relationship ◽  
High Fields ◽  
X Ray Absorption

X-ray Absorption Fine Structure (XAFS) measurements of the colossal magnetoresistance (CMR) sample La 0.79 Ca 0.21 MnO 3 at high fields indicate a decrease in the width parameter of the pair distribution function, σ, as the applied magnetic field is increased for T near Tc. The change in σ2 from the disordered polaron state varies approximately exponentially with magnetization irrespective of whether the sample magnetization was achieved through a change in temperature or the application of an external magnetic field. This suggests a more universal relationship between local structure and the sample magnetization than was previously indicated.

Engineering Porosity Through Defects in a Giant Pore Metal–Organic Framework

2020 ◽  
Author(s):  
Adam Sapnik ◽  
Duncan Johnstone ◽  
Sean M. Collins ◽  
Giorgio Divitini ◽  
Alice Bumstead ◽  
...  
Keyword(s):  
Distribution Function ◽  
Ball Milling ◽  
Local Structure ◽  
Pair Distribution Function ◽  
Function Analysis ◽  
Metal Organic Framework ◽  
Metal Organic Frameworks ◽  
Defect Engineering ◽  
Metal Organic ◽  
Unsaturated Metal Sites

<p>Defect engineering is a powerful tool that can be used to tailor the properties of metal–organic frameworks (MOFs). Here, we incorporate defects through ball milling to systematically vary the porosity of the giant pore MOF, MIL-100 (Fe). We show that milling leads to the breaking of metal–linker bonds, generating more coordinatively unsaturated metal sites, and ultimately causes amorphisation. Pair distribution function analysis shows the hierarchical local structure is partially</p><p>retained, even in the amorphised material. We find that the solvent toluene stabilises the MIL-100 (Fe) framework against collapse and leads to a substantial rentention of porosity over the non-stabilised material.</p>

Investigation of the Structure and Magnetic Properties of Bulk Amorphous FeCoYB Alloy

2017 ◽  
Vol 68 (9) ◽  
pp. 2162-2165 ◽  
Author(s):  
Katarzyna Bloch ◽  
Mihail Aurel Titu ◽  
Andrei Victor Sandu
Keyword(s):  
Magnetic Field ◽  
Magnetic Properties ◽  
Hyperfine Field ◽  
Irreversible Processes ◽  
Magnetization Process ◽  
Casting Method ◽  
The Core ◽  
Injection Casting ◽  
Core Losses ◽  
Microstructural Studies

The paper presents the results of structural and microstructural studies for the bulk Fe65Co10Y5B20 and Fe63Co10Y7B20 alloys. All the rods obtained by the injection casting method were fully amorphous. It was found on the basis of analysis of distribution of hyperfine field induction that the samples of Fe65Co10Y5B20 alloy are characterised with greater atomic packing density. Addition of Y to the bulk amorphous Fe65Co10Y5B20 alloy leads to the decrease of the average induction of hyperfine field value. In a strong magnetic field (i.e. greater than 0.4HC), during the magnetization process of the alloys, where irreversible processes take place, the core losses associated with magnetization and de-magnetization were investigated.

scholarly journals High-Resolution Observations of Emerging Magnetic Fields and Flux Tubes in Active Region Photosphere

1990 ◽  
Vol 138 ◽  
pp. 147-152 ◽  
Author(s):  
T. Tarbell ◽  
S. Ferguson ◽  
Z. Frank ◽  
R. Shine ◽  
A. Title ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Active Region ◽  
Solar Observatory ◽  
Disk Center ◽  
Line Center ◽  
Solar Photosphere ◽  
Flux Tubes ◽  
National Solar Observatory ◽  
La Palma ◽  
The Relationship

On 29 September 1988, filtergrams of the solar photosphere with excellent resolution (0.3 to 0.5 arcsecond) were obtained at the Swedish Solar Observatory on La Palma, Canary Islands. An outstanding 2.5 hour run of digital filtergram observations was obtained, looking at a small area within an active region near disk center. On 6 August 1987, an 80 minute run of similar observations was obtained at the Vacuum Tower Telescope of the National Solar Observatory at Sacramento Peak. Digital and video movies have been made of Dopplergrams, magnetograms, line center, continuum, and white light images. Several examples of magnetic field emergence and formation of flux tubes can be studied in detail in the movies. The relationship between photospheric bright points, “filigree”, the line center brightness, and the magnetic field has been established for individual images in analysis to date.

scholarly journals Observations of magnetic and kinetic helicity proxies

2012 ◽  
Vol 8 (S294) ◽  
pp. 13-24
Author(s):  
Hongqi Zhang
Keyword(s):  
Magnetic Field ◽  
Velocity Field ◽  
Magnetic Fields ◽  
Solar Atmosphere ◽  
Active Regions ◽  
Solar Dynamo ◽  
Magnetic Helicity ◽  
Vector Magnetograms ◽  
Topological Configuration ◽  
The Relationship

AbstractThe helicity is important to present the basic topological configuration of magnetic field in solar atmosphere. The distribution of magnetic helicity in solar atmosphere is presented by means of the observational (vector) magnetograms. As the kinetic helicity in the solar subatmosphere can be inferred from the velocity field based on the technique of the helioseismology and used to compare with the magnetic helicity in the solar atmosphere, the observational helicities provide the important chance for the confirmation on the generation of magnetic fields in the subatmosphere and solar dynamo models also. In this paper, we present the observational magnetic and kinetic helicity in solar active regions and corresponding questions, except the relationship with solar eruptive phenomena.

scholarly journals Assessment of the Relationship between Involvement, Entrepreneurial Orientation, and Performance of Christian Faith based Hotels in Kenya

2019 ◽  
Vol 8 (4) ◽  
pp. 90-104
Author(s):  
Ruth Wanjiku Muriithi ◽  
Kyalo Teresia Ngina ◽  
Kinyanjui Josphat Kamau
Keyword(s):  
Entrepreneurial Orientation ◽  
Organization Culture ◽  
Christian Faith ◽  
P Value ◽  
Cross Sectional Survey ◽  
Faith Based ◽  
Important Relationship ◽  
Significant Change ◽  
And Performance ◽  
The Relationship

The purpose of this study was to determine the relationship between involvement, Entrepreneurial orientation and performance of Christian Faith-Based Hotels (CFBHs) in Kenya. Involvement is the extent to which subordinate staff feels a sense of ownership and responsibility to the organization. Involvement has captured interest throughout the last decade because of its important relationship between the concept itself and its outcomes such as gaining competitive advantage and performance. Entrepreneurial Orientation is key as it determines the success or failure of Christian Faith-Based Hotels. The study was guided by the use of the Denison’s organizational model and used the mixed methods approach guided by a cross-sectional survey research design. The population of the study included 72 managers and 1878 subordinate staff from 24 Christian Faith-Based Hotels in Kenya and the sample size comprised 394 respondents. The data were analyzed using descriptive and inferential statistics. Findings revealed that organization culture involvement significantly influences the performance of Christian Faith-Based Hotels in Kenya. The dimensions of involvement Empowerment, Team Orientation, and Capability development were all found to have significant influences on performance in all critical ratios 2.829, 2.301 and 3.502 respectively which are all greater than the 1.96 Z score at 5% level of significance. Entrepreneurial orientation was also found to significantly moderate the relationship between organization culture involvement significantly influences the performance of Christian Faith-Based Hotels in Kenya. A significant change in R-square of 0.063 was found due to the inclusion of interaction terms between involvement dimensions and entrepreneurial orientation. The p-value of the F-change due to the change in R-square was found to be 0.043 implying a significant change but consequently, there is a significant moderating effect.

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