scholarly journals Deep melting reveals liquid structural memory and anomalous ferromagnetism in bismuth

2017 ◽  
Vol 114 (13) ◽  
pp. 3375-3380 ◽  
Author(s):  
Yu Shu ◽  
Dongli Yu ◽  
Wentao Hu ◽  
Yanbin Wang ◽  
Guoyin Shen ◽  
...  
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Electrical Resistance ◽  
Structural Characteristics ◽  
Critical Role ◽  
Melting Curve ◽  
Molten State ◽  
Pressure Independent ◽  
Temperature Liquid ◽  
Structural Memory

As an archetypal semimetal with complex and anisotropic Fermi surface and unusual electric properties (e.g., high electrical resistance, large magnetoresistance, and giant Hall effect), bismuth (Bi) has played a critical role in metal physics. In general, Bi displays diamagnetism with a high volumetric susceptibility (∼10−4). Here, we report unusual ferromagnetism in bulk Bi samples recovered from a molten state at pressures of 1.4–2.5 GPa and temperatures above ∼1,250 K. The ferromagnetism is associated with a surprising structural memory effect in the molten state. On heating, low-temperature Bi liquid (L) transforms to a more randomly disordered high-temperature liquid (L′) around 1,250 K. By cooling from above 1,250 K, certain structural characteristics of liquid L′ are preserved in L. Bi clusters with characteristics of the liquid L′ motifs are further preserved through solidification into the Bi-II phase across the pressure-independent melting curve, which may be responsible for the observed ferromagnetism.

scholarly journals Synthesis of MIL-100(Fe) at Low Temperature and Atmospheric Pressure

2013 ◽  
Vol 2013 ◽  
pp. 1-4 ◽  
Author(s):  
Jing Shi ◽  
Shengtao Hei ◽  
Huanhuan Liu ◽  
Yanghe Fu ◽  
Fumin Zhang ◽  
...  
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Atmospheric Pressure ◽  
Structural Characteristics ◽  
Metal Organic Framework ◽  
Potential Applications ◽  
Long Time ◽  
Metal Organic ◽  
Static Conditions ◽  
Mesoporous Metal

MIL-100(Fe), a mesoporous metal-organic framework (MOF), has a large BET specific surface area and pore volume with the presence of a significant amount of accessible Lewis acid metal sites upon dehydration. The structural characteristics of MIL-100(Fe) make it a good candidate for potential applications in gas storage, separation, and heterogeneous catalysis. Mainly, this MOF is obtained by the hydrothermal synthesis in a Teflon-lined autoclave at high temperature (>150°C) under static conditions. However, this method has several disadvantages such as high temperature, high (autogenous) pressure, long time, and comparable low MOF yield. Therefore, development of a facile method for synthesis of MIL-100(Fe) is vitally important for fundamental understanding and practical application. Herein, MIL-100(Fe) is synthesized by a facile low-temperature (<100°C) synthesis route at atmospheric pressure by reaction of metallic iron and trimesic acid in water. Due to our synthesis is conducted with agitation, higher MOF yield (>90%) still could be achieved, suggesting that this simple and energy saving method has the potential to be used practically.

Cu-Ni 55-45 Alloy

Alloy Digest ◽  
1974 ◽  
Vol 23 (1) ◽  
Keyword(s):  
Fracture Toughness ◽  
Corrosion Resistance ◽  
High Temperature ◽  
Low Temperature ◽  
Electrical Resistance ◽  
Heat Treating ◽  
Good Resistance ◽  
Temperature Performance ◽  
Resistance Alloy ◽  
Temperature Coefficient Of Resistivity

Abstract Cu-Ni 55-45 Alloy is an electrical-resistance alloy suitable for operation at temperatures up to about 930 F. It has a low temperature coefficient of resistivity and good resistance to corrosion. In thermocouples it can be used up to 1600 F. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness and fatigue. It also includes information on low and high temperature performance, and corrosion resistance as well as casting, forming, heat treating, machining, and joining. Filing Code: Cu-274. Producer or source: Electrical resistance and thermocouple alloy producers.

Ni-Cr 80-20 Alloy

Alloy Digest ◽  
1973 ◽  
Vol 22 (10) ◽  
Keyword(s):  
Corrosion Resistance ◽  
High Temperature ◽  
Low Temperature ◽  
Physical Properties ◽  
Electrical Resistance ◽  
Heat Treating ◽  
Temperature Performance ◽  
Resistance Alloy ◽  
Temperature Coefficient Of Resistivity ◽  
Corrosion And Oxidation

Abstract Ni-Cr 80-20 Alloy is an electrical-resistance alloy suitable for operation at temperatures up to 2100 F (1150 C). It has a low temperature coefficient of resistivity and is also highly resistant to corrosion and oxidation. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as creep and fatigue. It also includes information on low and high temperature performance, and corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: Ni-196. Producer or source: Electrical resistance alloy producers.

scholarly journals Low Temperature Joining and High Temperature Application of Segmented Half Heusler/Skutterudite Thermoelectric Joints

Materials ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 155 ◽  
Author(s):  
Weian Wang ◽  
Xiaoya Li ◽  
Ming Gu ◽  
Yunfei Xing ◽  
Yefeng Bao
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Electrical Resistance ◽  
Bonding Layer ◽  
High Temperature Application ◽  
High Melting Point ◽  
Before And After ◽  
Temperature Application ◽  
Service Behavior ◽  
Joining Process

A low temperature joining process has been developed to fabricate segmented half Heusler/skutterudite thermoelectric joints, and high temperature service behavior of the joints has been studied. The microstructure and electrical resistance across the joint before and after aging were investigated. The joint is well bonded and no cracks appear at the interfaces of the joint before and after aging, which can attribute to the formation of high melting point intermetallic compounds. The electrical resistance crosses the bonding layer smoothly and the contact resistance is low. These results show the process is effective, and promising for preparation of segmented thermoelectric devices.

Exsolution and inversion in pigeonite from the Whin Sill, Northern England

1978 ◽  
Vol 36 (1) ◽  
pp. 474-475
Author(s):  
P.P.K. Smith
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Homogeneous Nucleation ◽  
Silicate Mineral ◽  
Antiphase Boundaries ◽  
Two Phase ◽  
Primitive Form ◽  
The Core ◽  
Nucleation Mechanisms ◽  
And Inversion

Grains of pigeonite, a calcium-poor silicate mineral of the pyroxene group, from the Whin Sill dolerite have been ion-thinned and examined by TEM. The pigeonite is strongly zoned chemically from the composition Wo8En64FS28 in the core to Wo13En34FS53 at the rim. Two phase transformations have occurred during the cooling of this pigeonite:- exsolution of augite, a more calcic pyroxene, and inversion of the pigeonite from the high- temperature C face-centred form to the low-temperature primitive form, with the formation of antiphase boundaries (APB's). Different sequences of these exsolution and inversion reactions, together with different nucleation mechanisms of the augite, have created three distinct microstructures depending on the position in the grain.In the core of the grains small platelets of augite about 0.02μm thick have farmed parallel to the (001) plane (Fig. 1). These are thought to have exsolved by homogeneous nucleation. Subsequently the inversion of the pigeonite has led to the creation of APB's.

Superconducting Wind Generators with Capacities of 10 MW and Larger

2020 ◽  
Vol 10 (10) ◽  
pp. 59-67
Author(s):  
Victor N. ANTIPOV ◽  
◽  
Andrey D. GROZOV ◽  
Anna V. IVANOVA ◽  
◽  
...  
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Wind Power ◽  
State Of The Art ◽  
Superconducting Materials ◽  
Commercial Application ◽  
Synchronous Generators ◽  
High Temperature Superconducting ◽  
Wind Generators ◽  
Main Factor

The overall dimensions and mass of wind power units with capacities larger than 10 MW can be improved and their cost can be decreased by developing and constructing superconducting synchronous generators. The article analyzes foreign conceptual designs of superconducting synchronous generators based on different principles: with the use of high- and low-temperature superconductivity, fully superconducting or only with a superconducting excitation system, and with the use of different materials (MgB2, Bi2223, YBCO). A high cost of superconducting materials is the main factor impeding commercial application of superconducting generators. In view of the state of the art in the technology for manufacturing superconductors and their cost, a conclusion is drawn, according to which a synchronous gearless superconducting wind generator with a capacity of 10 MW with the field winding made of a high-temperature superconducting material (MgB2, Bi-2223 or YBCO) with the «ferromagnetic stator — ferromagnetic rotor» topology, with the stator diameter equal to 7—9 m, and with the number of poles equal to 32—40 has prospects for its practical use in the nearest future.

SOMERS LTA COPPER

Alloy Digest ◽  
1980 ◽  
Vol 29 (12) ◽  
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Physical Properties ◽  
Copper Foil ◽  
Heat Treating ◽  
Dielectric Substrates ◽  
Printed Circuits

Abstract SOMERS LTA Copper is a wrought copper foil that can be annealed at 350 F in 15 minutes to the full-soft condition; its use simplifies the manufacture of printed circuits (LTA = Low-Temperature Annealable). LTA Copper is especially useful for foil weights up to and including one ounce per square foot (0.0014-inch thick) for laminating to high-temperature dielectric substrates. This datasheet provides information on composition, physical properties, and elasticity as well as fatigue. It also includes information on forming, heat treating, and machining. Filing Code: Cu-407. Producer or source: Olin Corporation.

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