Publications by authors named "Kisi E"

Achieving more meaningful N conversion by reducing the energy input and carbon footprint is now being investigated through a method of N fixation instead of the Haber-Bosch process. Unfortunately, the electrochemical N reduction reaction (NRR) method as a rising approach currently still shows low selectivity (Faradaic efficiency < 10%) and high-energy consumption [applied potential at least - 0.2 V versus the reversible hydrogen electrode (RHE)].

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Energy-resolved neutron imaging experiments conducted on the Small Angle Neutron Scattering (SANS) instrument, Bilby, demonstrate how the capabilities of this instrument can be enhanced by a relatively simple addition of a compact neutron counting detector. Together with possible SANS sample surveying and location of the region of interest, this instrument is attractive for many imaging applications. In particular, the combination of the cold spectrum of the neutron beam and its pulsed nature enables unique non-destructive studies of the internal structure for samples that are opaque to other more traditional techniques.

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Metal matrix syntactic foams have been fabricated via counter-gravity infiltration of a packed bed of recycled expanded glass particles (EG) with A356 aluminum alloy. Particle shrinkage was studied and has been utilized to increase the particles' strength and tailor the mechanical properties of the expanded glass/metal syntactic foam (EG-MSF). The crushing strength of particles could be doubled by shrinking them for 20 min at 700 °C.

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The full triaxial stress state within individual particles in a monodisperse spherical granular assembly has been measured. This was made possible by neutron imaging and computed tomography combined with neutron diffraction strain measurement techniques and associated stress reconstruction. The assembly in question consists of 549 precision steel ball bearings under an applied axial load of 85 MPa in a cylindrical die.

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Nanolaminates such as the M(n + 1)AX(n) (MAX) phases are a material class with ab initio derived elasticity tensors published for over 250 compounds. We have for the first time experimentally determined the full elasticity tensor of the archetype MAX phase, Ti(3)SiC(2), using polycrystalline samples and in situ neutron diffraction. The experimental elastic constants show extreme shear stiffness, with c(44) more than five times greater than expected for an isotropic material.

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The structure of the relaxor ferroelectric Pb(Zn(0.3066)Nb(0.6133)Ti(0.

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The structure of the relaxor ferroelectric lead zinc niobium trioxide, Pb(Zn(1/3)Nb(2/3))O3, known as PZN, was determined at 4.2 and 295 K from very high resolution neutron powder diffraction data. The material is known for its extraordinary piezoelectric properties which are closely linked to the structure.

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Group-theoretical methods are used to analyze perovskite structures where both ferroelectric cation displacements and simple tilting of octahedral units are present. This results in a list of 40 different structures, each with a unique space-group symmetry. The list is compared with that of Aleksandrov & Bartolomé [Phase Transit.

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