cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.5286/isis.e.rb1920676-1
title: Micelle Formation in Lanthanide-Based DES

description: Deep eutectic solvents (DES) share many features with ionic liquids (ie. tunable physicochemical properties) which makes them viable green solvents that are less toxic than typical ILs. The most studied DES are mixtures of organic salts and hydrogen bond donors (HBD), that form strongly hydrogen-bonded room temperature liquids however "Type IV" DES are composed of inorganic salts with similar HBD. Our initial studies on lanthanide nitrate hydrate:urea mixtures show that these solvents have low viscosity, but high surface tensions, similar to those of water, and appear to also support micellization. Here we propose to study nonionic and cationic micelles in cerium nitrate hydrate:urea to determine micelle structures and properties in these novel solvents with a view to applying them as soft templates to create porous ceria for catalysis applications.
DOI: 10.5286/isis.e.rb2000109
title: Evolution of lattice spacing during aging heat treatment of IN718 Ni-base superalloy

description: Our recent joint publication on IN718 using neutron beam has drawn much attention in the high temperature field. The Journal (MMTA) editor Jonathan CORMIER at ENSMA in France, wants to carry out a joint study on IN718 with us since he has been using mechanical methods in characterising IN718. After a couple of discussion with him, we plan to perform an supplementary experiment to our previous ENGIN-X experiments on IN718. The experiment is to monitor the evolution of lattice spacing during aging heat treatment of IN718 Ni-base superalloy at 680 degree C, the measured lattice spacing evolution will be an important part to a precipitation kinetics model that we are trying to establish. The in situ aging experiment will be performed similar as our previous experiments in ENGIN-X.
DOI: 10.5286/isis.e.rb2000109-1
title: Evolution of lattice spacing during aging heat treatment of IN718 Ni-base superalloy

description: Our recent joint publication on IN718 using neutron beam has drawn much attention in the high temperature field. The Journal (MMTA) editor Jonathan CORMIER at ENSMA in France, wants to carry out a joint study on IN718 with us since he has been using mechanical methods in characterising IN718. After a couple of discussion with him, we plan to perform an supplementary experiment to our previous ENGIN-X experiments on IN718. The experiment is to monitor the evolution of lattice spacing during aging heat treatment of IN718 Ni-base superalloy at 680 degree C, the measured lattice spacing evolution will be an important part to a precipitation kinetics model that we are trying to establish. The in situ aging experiment will be performed similar as our previous experiments in ENGIN-X.
DOI: 10.5286/isis.e.rb1820151
title: The nature of excitations in a molecular Haldane system

description: It is well known that an S = 1 antiferromagnetic spin chain is predicted to have a quantum disordered ground state and a gap in its excitation spectrum. This so-called Haldane gap is topological in origin and contrasts dramatically with the case for S = 1/2, whose topology leads to a gapless spectrum. We have recently synthesised an intriguing new series based on S = 1 NiX2(3,5-lutidine)4 molecular complexes formed from quasi-one-dimensional columns of Ni-X...X-Ni. In an experiment at PSI in 2017 we showed that NiI2(3,5-lutidine)4 remains disordered down to 30 mK, suggesting that the system is a highly successful realization of a Haldane chain system. We now plan to investigate the order and dynamics of the system in high field as we close the spin gap and drive the system through a quantum critical point (QCP) in a new experiment, only possible using the HIFI spectrometer at ISIS.
DOI: 10.5286/isis.e.rb1820151-1
title: The nature of excitations in a molecular Haldane system

description: It is well known that an S = 1 antiferromagnetic spin chain is predicted to have a quantum disordered ground state and a gap in its excitation spectrum. This so-called Haldane gap is topological in origin and contrasts dramatically with the case for S = 1/2, whose topology leads to a gapless spectrum. We have recently synthesised an intriguing new series based on S = 1 NiX2(3,5-lutidine)4 molecular complexes formed from quasi-one-dimensional columns of Ni-X...X-Ni. In an experiment at PSI in 2017 we showed that NiI2(3,5-lutidine)4 remains disordered down to 30 mK, suggesting that the system is a highly successful realization of a Haldane chain system. We now plan to investigate the order and dynamics of the system in high field as we close the spin gap and drive the system through a quantum critical point (QCP) in a new experiment, only possible using the HIFI spectrometer at ISIS.
DOI: 10.5286/isis.e.rb1820151-2
title: The nature of excitations in a molecular Haldane system

description: It is well known that an S = 1 antiferromagnetic spin chain is predicted to have a quantum disordered ground state and a gap in its excitation spectrum. This so-called Haldane gap is topological in origin and contrasts dramatically with the case for S = 1/2, whose topology leads to a gapless spectrum. We have recently synthesised an intriguing new series based on S = 1 NiX2(3,5-lutidine)4 molecular complexes formed from quasi-one-dimensional columns of Ni-X...X-Ni. In an experiment at PSI in 2017 we showed that NiI2(3,5-lutidine)4 remains disordered down to 30 mK, suggesting that the system is a highly successful realization of a Haldane chain system. We now plan to investigate the order and dynamics of the system in high field as we close the spin gap and drive the system through a quantum critical point (QCP) in a new experiment, only possible using the HIFI spectrometer at ISIS.
DOI: 10.5286/isis.e.rb1920053
title: Local structure in PMN-PT relaxor ferroelectrics

description: The proposed experiments will provide neutron total-scattering data for elucidating the nanoscale ordering of polar atomic displacements that underlie the commercially viable piezoelectric properties in a classical oxide ferroelectric system. These materials find use in applications ranging from sonar transducers in naval radar systems to fuel injectors in diesel automobile engines. The currently missing detailed knowledge of atomic arrangements is required to facilitate the design of new formulations with the improved piezoelectric performance.
DOI: 10.5286/isis.e.rb1920053-1
title: Local structure in PMN-PT relaxor ferroelectrics

description: The proposed experiments will provide neutron total-scattering data for elucidating the nanoscale ordering of polar atomic displacements that underlie the commercially viable piezoelectric properties in a classical oxide ferroelectric system. These materials find use in applications ranging from sonar transducers in naval radar systems to fuel injectors in diesel automobile engines. The currently missing detailed knowledge of atomic arrangements is required to facilitate the design of new formulations with the improved piezoelectric performance.
DOI: 10.5286/isis.e.rb1920400
title: Structural examination of self-assembled floating membranes below grafted lipid SAMs

description: Robust, reliable, and protein-free bacterial membrane mimicking systems compatible with the high through put screening techniques will largely facilitate the discovery of new antibiotics. None of the published approaches have demonstrated the functionality beyond the scientific experimental level, which is required by the pharmaceutical industry. Thus, systematic, reliable in vitro screening of membrane-targeting drug candidates remains a challenging task. We have developed an experimental system to mimic Gram-negative bacterial membrane based on molecular self-assembly and vesicle fusion. The neutron based techniques are the only ones which allow dissecting the nano-scale vertical architecture of lipid membranes and unambiguously determining buried aqueous inter-layer. Therefore, neutron reflection study is a necessary prerequisite before starting large scale interaction analysis.
DOI: 10.5286/isis.e.rb1920400-1
title: Structural examination of self-assembled floating membranes below grafted lipid SAMs

description: Robust, reliable, and protein-free bacterial membrane mimicking systems compatible with the high through put screening techniques will largely facilitate the discovery of new antibiotics. None of the published approaches have demonstrated the functionality beyond the scientific experimental level, which is required by the pharmaceutical industry. Thus, systematic, reliable in vitro screening of membrane-targeting drug candidates remains a challenging task. We have developed an experimental system to mimic Gram-negative bacterial membrane based on molecular self-assembly and vesicle fusion. The neutron based techniques are the only ones which allow dissecting the nano-scale vertical architecture of lipid membranes and unambiguously determining buried aqueous inter-layer. Therefore, neutron reflection study is a necessary prerequisite before starting large scale interaction analysis.
DOI: 10.5286/isis.e.rb1920691
title: Measurement of the Orientation and Zero-point Energy of I2 on Graphite

description: Molecular self-assembly directed by non-covalent interactions presents a unique opportunity to create precisely engineered functional materials. Halogen bonding is a widely studied interaction in three dimensions but there is limited research in two dimensions. Previous work in the Clarke group has focused structural determination of monolayers on graphite using two-dimensional diffraction; however, this technique can be insensitive to orientation perpendicular to the surface. We propose to measure the gamma resonance spectrum for I2 on graphite with the incident neutron beam parallel and perpendicular to the graphite surface. Comparison of the mean kinetic energies of the iodine atoms in these directions allows for determination of the orientation of the molecule with respect to the surface.
DOI: 10.5286/isis.e.rb1920691-1
title: Measurement of the Orientation and Zero-point Energy of I2 on Graphite

description: Molecular self-assembly directed by non-covalent interactions presents a unique opportunity to create precisely engineered functional materials. Halogen bonding is a widely studied interaction in three dimensions but there is limited research in two dimensions. Previous work in the Clarke group has focused structural determination of monolayers on graphite using two-dimensional diffraction; however, this technique can be insensitive to orientation perpendicular to the surface. We propose to measure the gamma resonance spectrum for I2 on graphite with the incident neutron beam parallel and perpendicular to the graphite surface. Comparison of the mean kinetic energies of the iodine atoms in these directions allows for determination of the orientation of the molecule with respect to the surface.
DOI: 10.25919/5df1d7cc6835b
title: Parkes observations for project P971 semester 2019OCTS_04

description: We propose timing observations of the relativistic pulsar - white-dwarf binary PSR J1141-6545. This unique system offers access to a wide range of physics, from relativistic phenomena through pulsar emission cone studies, to the structure and distribution of interstellar plasma along our line-of-sight. The recently installed Parkes Ultra Wide Band Low Frequency (UWL) receiver has opened up the possibility of performing first-ever studies of its orbital dynamics at high temporal resolution and study of the effects of the intra-binary medium on the dispersion and polarisation of the pulse profile. Our analysis of data obtained to date suggests that the pulsar would precess away from our line-of-sight in the next 3-5 years. Hence, regular observations are crucial to maximizing its science outcome
DOI: 10.5286/isis.e.rb1920236
title: Kitaev spin liquid in the Co-based honeycomb system BaCo2(P0.85V0.15)2O8

description: The newly reported compound BaCo2(P1-xVx)2O8 fulfills the necessary condition for hosting the Kitaev-type interactions. In particular, for the x=0.15 composition, the dc and ac magnetic susceptibility results show a substantial enhancement below 100 K and a spin-glass ground state through Tg ~ 5 K. Given the small Curie-Weiss temperature (-3.2 K) relative to an energy scale of Tg, the antiferromagnetic Heisenberg and ferromagnetic Kitaev interactions are present. Thermodynamic measurements show that the application of an external field enhances quantum fluctuations. All the previous experimental results suggest that the structural geometry, chemical disorder, and external field cooperatively promote a Kitaev QSL-like state. In this project, we aim at performing ZF- and LF-muSR experiments on BaCo2(P0.85V0.15)2O8 to test a proximity to a Kitaev spin liquid.
DOI: 10.5286/isis.e.rb1920236-1
title: Kitaev spin liquid in the Co-based honeycomb system BaCo2(P0.85V0.15)2O8

description: The newly reported compound BaCo2(P1-xVx)2O8 fulfills the necessary condition for hosting the Kitaev-type interactions. In particular, for the x=0.15 composition, the dc and ac magnetic susceptibility results show a substantial enhancement below 100 K and a spin-glass ground state through Tg ~ 5 K. Given the small Curie-Weiss temperature (-3.2 K) relative to an energy scale of Tg, the antiferromagnetic Heisenberg and ferromagnetic Kitaev interactions are present. Thermodynamic measurements show that the application of an external field enhances quantum fluctuations. All the previous experimental results suggest that the structural geometry, chemical disorder, and external field cooperatively promote a Kitaev QSL-like state. In this project, we aim at performing ZF- and LF-muSR experiments on BaCo2(P0.85V0.15)2O8 to test a proximity to a Kitaev spin liquid.
DOI: 10.5286/isis.e.rb1920254
title: Molecular recognition in the LysM/Carbohydrate system

description: Molecular recognition of carbohydrates regulates many essential biological processes in living organisms. One carbohydrate binding module (CBM) conserved across all kingdoms is LysM: which is present in bacterial extra-cellular proteins including hydrolases, adhesins and virulence factors such as Protein A from Staphylococcus aureus. LysM modules consist of 4350 amino acids that adopt a highly conserved beta-alpha-alpha-beta fold, with particularly high sequence conservation in the first 16 residues1,28,17. Prokaryotic LysM modules bind peptidoglycan, the main component of the bacterial cell wall, made of alternating N-acetylglucosamine (GlcNAc) and Nacetylmuramic acid (MurNAc) residues, substituted by short peptide stems
DOI: 10.5286/isis.e.rb1920363
title: A depth-resolved study of magnetoelectric coupling in multiferroic PMN-PT/FeRh using PNR

description: Multiferroic systems allow the modulation of magnetic properties through electric potentials. Advances in engineering atomic interfaces of heterogeneous thin-films have enabled a significant increase in magnetoelectric coupling compared with conventional single phase materials. This opens a range of interesting and exciting possibilities for new spintronic devices with applications in next-generation data storage technologies, such as antiferromagnetic memory resistors. One system with real potential is FeRh where a change in lattice parameter accompanies a change from anti- to ferro-magnetic ordering. Here we propose to use PNR to investigate this metamagnetic transition by manipulating the strain in FeRh thin films using ferroelectric PMN-PT substrates. The key objective of this work is to identify depth-dependent interplay between electric field and magnetic order in this system.
DOI: 10.5286/isis.e.rb1920363-1
title: A depth-resolved study of magnetoelectric coupling in multiferroic PMN-PT/FeRh using PNR

description: Multiferroic systems allow the modulation of magnetic properties through electric potentials. Advances in engineering atomic interfaces of heterogeneous thin-films have enabled a significant increase in magnetoelectric coupling compared with conventional single phase materials. This opens a range of interesting and exciting possibilities for new spintronic devices with applications in next-generation data storage technologies, such as antiferromagnetic memory resistors. One system with real potential is FeRh where a change in lattice parameter accompanies a change from anti- to ferro-magnetic ordering. Here we propose to use PNR to investigate this metamagnetic transition by manipulating the strain in FeRh thin films using ferroelectric PMN-PT substrates. The key objective of this work is to identify depth-dependent interplay between electric field and magnetic order in this system.
DOI: 10.5286/isis.e.rb1920408
title: Hydrogen impurity in solar cell materials CIGS and CZTS

description: In this proposal we intend to complete the characterization of the hydrogen impurity in solar cell materials Cu2ZnSnS4 (CZTS) and Cu(In,Ga)Se2 (CIGS), by using the positive muons as an analogue. In particular, we intend to characterize the diffusion behaviour above room temperature and look for possible trapping of muons in native defects (likely the acceptor copper vacancies, leading to its passivation). We also intend to characterize the acceptor configuration of the isolated hydrogen impurity by determining its hyperfine interaction, as well as its possible ionization energy.
DOI: 10.5286/isis.e.rb1920408-1
title: Hydrogen impurity in solar cell materials CIGS and CZTS

description: In this proposal we intend to complete the characterization of the hydrogen impurity in solar cell materials Cu2ZnSnS4 (CZTS) and Cu(In,Ga)Se2 (CIGS), by using the positive muons as an analogue. In particular, we intend to characterize the diffusion behaviour above room temperature and look for possible trapping of muons in native defects (likely the acceptor copper vacancies, leading to its passivation). We also intend to characterize the acceptor configuration of the isolated hydrogen impurity by determining its hyperfine interaction, as well as its possible ionization energy.
DOI: 10.5286/isis.e.rb1920449
title: The Molecular Architecture of Cationic Lipid Nanoparticles for siRNA Delivery

description: The proposal aims to use SANS and contrast variation to determine the detailed molecular architecture of lipid nanoparticles (LNPs) containing the nucleic acid, siRNA. The information thus gained will aid an understanding of the relationship between the cationic lipids used to prepare the LNP, the structure of the LNP they form and the LNP's therapeutic activity. Recently, work in our group has shown that the preparation of LNPs using trichain cationic lipids results in better siRNA delivery than when using the more usual dichain cationic lipids. The current proposal will therefore use SANS to compare the molecular architecture of LNPs prepared using trichain cationic lipids with that seen with the corresponding dichain lipids and relate this to the ability of the LNPs to deliver siRNA. The work is important for the development of improved nucleic acid delivery vehicles as medicines.
DOI: 10.5286/isis.e.rb1920449-1
title: The Molecular Architecture of Cationic Lipid Nanoparticles for siRNA Delivery

description: The proposal aims to use SANS and contrast variation to determine the detailed molecular architecture of lipid nanoparticles (LNPs) containing the nucleic acid, siRNA. The information thus gained will aid an understanding of the relationship between the cationic lipids used to prepare the LNP, the structure of the LNP they form and the LNP's therapeutic activity. Recently, work in our group has shown that the preparation of LNPs using trichain cationic lipids results in better siRNA delivery than when using the more usual dichain cationic lipids. The current proposal will therefore use SANS to compare the molecular architecture of LNPs prepared using trichain cationic lipids with that seen with the corresponding dichain lipids and relate this to the ability of the LNPs to deliver siRNA. The work is important for the development of improved nucleic acid delivery vehicles as medicines.
DOI: 10.5286/isis.e.rb1670565-3
title: Probing the Superconducting Ground State of Single Crystal Organic Superconductor lambda-(BETS)2GaCl4

description: lambda-(BETS)2GaCl4 is a non-magnetic anion-based organic superconductor SC attracting interest since its Fe analog becomes superconductor by applying 33 T. Both have similar Tc ~5 K. We measured TF and ZF-mSR down to 0.3K in the powder sample. The temperature dependence of the damping rate s(T) of the muon-spin precession related to the penetration depth was investigated in TF= 30 and 60 G. They indicate that SC is not stabilized even at 0.3 K or that there are nodes in the SC gap. We found a possible signature of time-reversal symmetry breaking (TRSB) since we detect slightly enhancement of relaxation rate below Tc in ZF-mSR. For extracting intrinsic & clear result, we are now planning to measure single crystals which can be aligned to make angular dependence measurement possible. We plan to align crystals in order to measure s(T) and TRSB and discuss SC gap symmetry by TF and ZF-mSR.
DOI: 10.5286/isis.e.rb1920237
title: Quantum spin liquid ground state in the Co-based triangular antiferromagnet Na2BaCo(PO4)2

description: A triangular lattice occupies a special position in the quantum spin-liquid (QSL) physics. Although the triangular-lattice Heisenberg antiferromagnet is known to evade a QSL, several ingredients including exchange randomness, spin-orbit coupling, anisotropic and biquadratic exchange interactions have been controversially discussed as a route to stabilize QSLs. Recently, the Co-based triangular antiferromagnet Na2BaCo(PO4)2 has emerged as a new candidate for QSL, The triangular layers of Co2+ (jeff = 1/2) ions are separated by a single layer of nonmagnetic BaO12 polyhedra and stacked along c-axis. Our preliminary results defied magnetic and structural phase transitions down to 50 mK. Rather, the large residual magnetic entropy is retained at low temperatures, indicating abundant low-lying magnetic excitations. With the aid of muSR, we will corroborate a truly dynamic ground state.
DOI: 10.5286/isis.e.rb1920237-1
title: Quantum spin liquid ground state in the Co-based triangular antiferromagnet Na2BaCo(PO4)2

description: A triangular lattice occupies a special position in the quantum spin-liquid (QSL) physics. Although the triangular-lattice Heisenberg antiferromagnet is known to evade a QSL, several ingredients including exchange randomness, spin-orbit coupling, anisotropic and biquadratic exchange interactions have been controversially discussed as a route to stabilize QSLs. Recently, the Co-based triangular antiferromagnet Na2BaCo(PO4)2 has emerged as a new candidate for QSL, The triangular layers of Co2+ (jeff = 1/2) ions are separated by a single layer of nonmagnetic BaO12 polyhedra and stacked along c-axis. Our preliminary results defied magnetic and structural phase transitions down to 50 mK. Rather, the large residual magnetic entropy is retained at low temperatures, indicating abundant low-lying magnetic excitations. With the aid of muSR, we will corroborate a truly dynamic ground state.
DOI: 10.5286/isis.e.rb1920254-1
title: Molecular recognition in the LysM/Carbohydrate system

description: Molecular recognition of carbohydrates regulates many essential biological processes in living organisms. One carbohydrate binding module (CBM) conserved across all kingdoms is LysM: which is present in bacterial extra-cellular proteins including hydrolases, adhesins and virulence factors such as Protein A from Staphylococcus aureus. LysM modules consist of 4350 amino acids that adopt a highly conserved beta-alpha-alpha-beta fold, with particularly high sequence conservation in the first 16 residues1,28,17. Prokaryotic LysM modules bind peptidoglycan, the main component of the bacterial cell wall, made of alternating N-acetylglucosamine (GlcNAc) and Nacetylmuramic acid (MurNAc) residues, substituted by short peptide stems