Archaeal cyclopentane fragment in a surfactant's hydrophobic tail decreases the Krafft point

The electroresistance, ER effect of La0.85Ag0.15Mn1-xMoxO3 (x = 0.00 and 0.05) samples prepared using solid method are investigated. The increased of applied current from 5 mA to 10 mA does not change the metal-insulator transition temperature, TMI for both samples however decreased the resistivity in the temperature region of 50 K – 300 K. Both samples exhibit large ER effect at low temperature region. At TMI, the ER value is 75.5% (x =0) and decrease to 34.15% (x = 0.05). However, at 300 K, the value of ER increases to 57 % for Mo substituted sample, and the value decreases to 6.4% for the x =0 sample. The enhanced ER effect at 300 K may be due to the growth of conductive filaments under increased applied current. The increase of applied current may perturb the arrangement of magnetic inhomogeneity induced by Mo substitution, result in reduction of resistivity and lead to the observation of ER effect. These findings suggest potential application of La0.85Ag0.15Mn1-xMoxO3 (x = 0.05) in spintronic devices.

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CPFD simulation on particle behaviour in an entrained-flow gasifier

Clean Energy ◽

10.1093/ce/zkz032 ◽

2020 ◽

Vol 4 (1) ◽

pp. 75-84

Author(s):

Yongshi Liang ◽

Cliff Y Guo ◽

Xianglong Zhao ◽

Qiang Qin ◽

Yi Cheng ◽

...

Keyword(s):

Low Temperature ◽

Residence Time ◽

Temperature Region ◽

Recirculation Zone ◽

Dynamics Simulation ◽

Entrained Flow ◽

Fast Reactions ◽

Entrained Flow Gasifier ◽

Gas Expansion ◽

Entrained Flow Gasification

Abstract A computational particle fluid dynamics simulation model for entrained-flow gasification was established in this study. The simulation results agree with the experimental data. The detailed particle information and residence-time distribution were obtained by injecting particle tracers in the simulation. The results show that the particles in the gasifier can be classified into three flowing zones, i.e. a fast-flowing zone, a recirculation zone and a spreading zone. The criterion for this classification was also provided. The rapid gas expansion caused by the fast reactions plays a significant role in forming the particle stream into these three zones. It accelerates the particles in the centre of the gasifier while pushing the particles near the expansion edge into the gas recirculation. Also, the concentrated oxygen distribution in the gasifier results in the formation of high- and low-temperature regions. The particles in the fast-flowing zone flow directly through the high-temperature region and most of these particles in this zone were fully reacted with a short residence time. Since particles in the recirculation zone are in a relatively low-temperature region, most of these particles are not fully gasified, although with a long residence time. The rest of particles in the spreading zone show moderate properties between the above two zones.

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Origin of Diversified Transport Properties of MgB2

International Journal of Modern Physics B ◽

10.1142/s0217979203021599 ◽

2003 ◽

Vol 17 (18n20) ◽

pp. 3672-3674

Author(s):

Kijoon H. P. Kim ◽

C. U. Jung ◽

Heon-Jung Kim ◽

Min-Seok Park ◽

Mun-Seog Kim ◽

...

Keyword(s):

Low Temperature ◽

Transport Properties ◽

Temperature Region ◽

Residual Resistivity ◽

Transition Width ◽

Residual Resistivity Ratio ◽

Resistivity Ratio ◽

Excess Mg

We investigated the transport properties of MgB 2 while changing the contents of excess Mg. The samples containing almost no excess Mg showed the highest Tc and the sharpest transition width (ΔTc). A residual resistivity ratio (RRR) of ~ 5.8, and a magnetoresistance (MR) of 12%, at 40 K, were obtained for this stoichiometric sample. Moreover, no upturn of resistivity in a low temperature region at 10 Tesla was observed. However, the samples containing appreciable amounts of excess Mg showed quite different behaviors; the values of ΔTc, RRR and MR were much larger. Surprisingly, big upturn appeared in this Mg-excess MgB 2

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