cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.5286/isis.e.rb2000162
title: Finding the k-gap: phonon dynamics in liquid lead

description: We are investigating the phonon theory of thermodynamics in liquids which is still awaiting experimental confirmation. At low temperatures the collective dynamics of liquids have close analogues to solids when the local residence time, t, of an atom exceeds its periods of vibration. This results in a rigid local structure at times shorter than t in liquids that support transverse modes, but only with wave-vectors exceeding kg = 1/(2*c*t), the k-gap. Despite this prediction and the growing interest from the liquid and diffraction communities, there is no experimental evidence for the k-gap. Liquid lead is a strong candidate for the first experimental measurement of the k-gap due to its large predicted kg. The main purpose of this proposal is to find the first experimental evidence for the k-gap and provide long-awaited experimental confirmation for a critical addition to liquid theory.
DOI: 10.5286/isis.e.rb2000162-1
title: Finding the k-gap: phonon dynamics in liquid lead

description: We are investigating the phonon theory of thermodynamics in liquids which is still awaiting experimental confirmation. At low temperatures the collective dynamics of liquids have close analogues to solids when the local residence time, t, of an atom exceeds its periods of vibration. This results in a rigid local structure at times shorter than t in liquids that support transverse modes, but only with wave-vectors exceeding kg = 1/(2*c*t), the k-gap. Despite this prediction and the growing interest from the liquid and diffraction communities, there is no experimental evidence for the k-gap. Liquid lead is a strong candidate for the first experimental measurement of the k-gap due to its large predicted kg. The main purpose of this proposal is to find the first experimental evidence for the k-gap and provide long-awaited experimental confirmation for a critical addition to liquid theory.
DOI: 10.5286/isis.e.rb2010561
title: Magnetic excitations in hyperkagome iridate Na4Ir3O8

description: The hyperkagome iridate Na4Ir3O8 has been attracting attentions as a candidate for three-dimensional quantum spin liquid. The S = 1/2 Heisenberg antiferromagnetic model on a frustrated hyperkagome lattice has been originally studied to understand the spin-liquid behavior. In fact, strong spin-orbit coupling of Ir likely yields other anisotropic magnetic interactions which superpose on the Heisenberg coupling. The magnetic interactions in Na4Ir3O8 thus can be more complex than the pure Heisenberg model, and further experimental investigations should be required. However, the strong neutron absorption of natural Ir has hampered the investigation of magnetic excitations by neutron scattering. We try to obtain the information of magnetic interactions by inelastic neutron scattering on MERLIN with using 193Ir enriched sample which substantially reduces neutron absorption.
DOI: 10.5286/isis.e.rb2010561-1
title: Magnetic excitations in hyperkagome iridate Na4Ir3O8

description: The hyperkagome iridate Na4Ir3O8 has been attracting attentions as a candidate for three-dimensional quantum spin liquid. The S = 1/2 Heisenberg antiferromagnetic model on a frustrated hyperkagome lattice has been originally studied to understand the spin-liquid behavior. In fact, strong spin-orbit coupling of Ir likely yields other anisotropic magnetic interactions which superpose on the Heisenberg coupling. The magnetic interactions in Na4Ir3O8 thus can be more complex than the pure Heisenberg model, and further experimental investigations should be required. However, the strong neutron absorption of natural Ir has hampered the investigation of magnetic excitations by neutron scattering. We try to obtain the information of magnetic interactions by inelastic neutron scattering on MERLIN with using 193Ir enriched sample which substantially reduces neutron absorption.
DOI: 10.5286/isis.e.rb2010167
title: The Structure of Anisotropic Nb2O5 Nanocrystals

description: This proposal aims to study the intricacies in the structure of niobium pentoxide (Nb2O5) materials. When tested in batteries and supercapacitor devices, niobium pentoxide has shown promising properties. We have produced a high surface area, nano-structured niobium oxide material, with a structure that cannot be effectively identified using lab based techniques. We would like to use this opportunity to learn about the structure and probe how this it is related to the other crystalline phases that are already well defined. Understanding how the atoms are distributed will elude to paths and tunnels in which ions can move and thus energy can be stored. We suggest that with proper knowledge of its structure, there is significant opportunity for further improvement of its electrochemical properties.
DOI: 10.5286/isis.e.rb2010167-1
title: The Structure of Anisotropic Nb2O5 Nanocrystals

description: This proposal aims to study the intricacies in the structure of niobium pentoxide (Nb2O5) materials. When tested in batteries and supercapacitor devices, niobium pentoxide has shown promising properties. We have produced a high surface area, nano-structured niobium oxide material, with a structure that cannot be effectively identified using lab based techniques. We would like to use this opportunity to learn about the structure and probe how this it is related to the other crystalline phases that are already well defined. Understanding how the atoms are distributed will elude to paths and tunnels in which ions can move and thus energy can be stored. We suggest that with proper knowledge of its structure, there is significant opportunity for further improvement of its electrochemical properties.
DOI: 10.5286/isis.e.rb2010306
title: Characterisation of E. coli outer membrane vesicles by small angle neutron scattering

description: Vaccines are a promising solution to antimicrobial resistance as they help improve animal health and production as well as human health by providing safe foods, not to mention reducing the transmission of animal-diseases to humans. Outer membrane vesicles (OMVs) are naturally secreted by Gram-negative bacteria. They are proven to be safe in humans; OMVs are currently used as a main component of the licensed meningococcal serogroup B vaccines for humans. Genetic engineering of proteins inserted in OMVs will allow us to produce vaccines containing the desired antigens. However, the OMV heterogeneity is a main hurdle for its large-scale production. We aim to redesign OMVs with minimal components while maintaining its efficacy. The redesigned OMVs will be characterised by neutron scattering and other techniques to assess their stability in solutions.
DOI: 10.5286/isis.e.rb2010306-1
title: Characterisation of E. coli outer membrane vesicles by small angle neutron scattering

description: Vaccines are a promising solution to antimicrobial resistance as they help improve animal health and production as well as human health by providing safe foods, not to mention reducing the transmission of animal-diseases to humans. Outer membrane vesicles (OMVs) are naturally secreted by Gram-negative bacteria. They are proven to be safe in humans; OMVs are currently used as a main component of the licensed meningococcal serogroup B vaccines for humans. Genetic engineering of proteins inserted in OMVs will allow us to produce vaccines containing the desired antigens. However, the OMV heterogeneity is a main hurdle for its large-scale production. We aim to redesign OMVs with minimal components while maintaining its efficacy. The redesigned OMVs will be characterised by neutron scattering and other techniques to assess their stability in solutions.
DOI: 10.5286/isis.e.rb2010722
title: Exploration of Interfacial Skyrmion States

description: The presence of a surface or an interface has profound impacts not only on the electronic but also on the magnetic properties of a system. In skyrmion systems, where the phase-stabilising energy balance is very finely tuned, the surface can strongly affect the skyrmion state, even complete inverting its character. However, there are only few experimental studies of this important phenomenon, which is critical as all applications make use of surfaces and interfaces. Here, we are proposing to systematically study the effect by altering the interface. Our very successful soft x-ray scattering studies are not possible due to the absorption of the added layers. PNR is the only method that allow for a deeper look into the magnetic properties of a heterostructure.
DOI: 10.5286/isis.e.rb2010722-1
title: Exploration of Interfacial Skyrmion States

description: The presence of a surface or an interface has profound impacts not only on the electronic but also on the magnetic properties of a system. In skyrmion systems, where the phase-stabilising energy balance is very finely tuned, the surface can strongly affect the skyrmion state, even complete inverting its character. However, there are only few experimental studies of this important phenomenon, which is critical as all applications make use of surfaces and interfaces. Here, we are proposing to systematically study the effect by altering the interface. Our very successful soft x-ray scattering studies are not possible due to the absorption of the added layers. PNR is the only method that allow for a deeper look into the magnetic properties of a heterostructure.
DOI: 10.5286/isis.e.rb1970102
title: Electron transfer channel in the sugar recognition system assembled on gold nano particles

description: The recently reported electrochemical sugar recognition system consisting of pheylboronic acids and ruthenium (Ru) complexes, assembled on a gold nano particle with a diameter of 10 nm, attracts much interest because of its high sensitivity for various sugar molecules. When sugar molecules are attached to the phenilboronic site, the responce of electrochemical voltammetry at Ru site drastically changes. The purpose of this study is to find out a channel of the electron transfer from the phenilboronic site to the Ru-complex via alkyl chains, connecting them to the surface of gold particle. Finding of this channel must be a key to understand the sugar-recognition mechanism. If this channel does exist, one-dimensional motion of electrons is expected within alkyl chains, which can be detected by the muon-labelling measurement with the LF-muSR technique.
DOI: 10.5286/isis.e.rb1970102-1
title: Electron transfer channel in the sugar recognition system assembled on gold nano particles

description: The recently reported electrochemical sugar recognition system consisting of pheylboronic acids and ruthenium (Ru) complexes, assembled on a gold nano particle with a diameter of 10 nm, attracts much interest because of its high sensitivity for various sugar molecules. When sugar molecules are attached to the phenilboronic site, the responce of electrochemical voltammetry at Ru site drastically changes. The purpose of this study is to find out a channel of the electron transfer from the phenilboronic site to the Ru-complex via alkyl chains, connecting them to the surface of gold particle. Finding of this channel must be a key to understand the sugar-recognition mechanism. If this channel does exist, one-dimensional motion of electrons is expected within alkyl chains, which can be detected by the muon-labelling measurement with the LF-muSR technique.
DOI: 10.5286/isis.e.rb1920098-2
title: Probing the dimensional crossover of critical fluctuations in ferromagnetic quantum critical system UCoSi2

description: In recent times, study of quantum critical point(QCP) and quantum phase transition(QPT) has become one of the most appealing research topics. Notably, near the critical point one observes unconventional power-law type divergence of different physical properties such as electrical resistivity or heat capacity. Such unusual behavior solely depend on the dimensionality of the critical spin fluctuations. We have recently investigated UCoSi2 which is proposed to be situated very close to ferromagnetic (FM) quantum critical point. Interestingly, it exhibits a dimensional crossover of critical fluctuations from 2D-FM to 3D-AFM which has not been experimentally observed before. μSR is an excellent technique to probe such spin fluctuations. Therefore, we propose to carry out μSR measurements on UCoSi2 to verify this dimensional crossover and study the spin dynamics.
DOI: 10.5286/isis.e.rb2010360
title: Localization of Amphotericin B in self nano-emulsifying drug delivery systems

description: Amphotericin B (AmB) is a life-saving drug in the treatment of serious systemic fungal infections. Oral delivery of AmB is considered the most favourable route with lower cost and higher patient compliance, in particular for paediatric use. However, AmB has poor aqueous solubility causing very low oral bioavailability. Here, this drawback is resolved by employing a drug-phospholipid complex strategy. The AmB complex displays improved bioavailability when incorporated in lipid-based formulations. When dispersed in water, the formulation forms a colloidal oil-in-water emulsion of nanosized oil droplets. A better understanding of how the drug complex behaves can lead to a strategy for higher bioavailability. We therefore wish to study the localization of AmB in the emulsion droplets (core/shell) and follow the digestion of the lipid-based droplets during pH-controlled lipolysis experiments.
DOI: 10.5286/isis.e.rb2010360-1
title: Localization of Amphotericin B in self nano-emulsifying drug delivery systems

description: Amphotericin B (AmB) is a life-saving drug in the treatment of serious systemic fungal infections. Oral delivery of AmB is considered the most favourable route with lower cost and higher patient compliance, in particular for paediatric use. However, AmB has poor aqueous solubility causing very low oral bioavailability. Here, this drawback is resolved by employing a drug-phospholipid complex strategy. The AmB complex displays improved bioavailability when incorporated in lipid-based formulations. When dispersed in water, the formulation forms a colloidal oil-in-water emulsion of nanosized oil droplets. A better understanding of how the drug complex behaves can lead to a strategy for higher bioavailability. We therefore wish to study the localization of AmB in the emulsion droplets (core/shell) and follow the digestion of the lipid-based droplets during pH-controlled lipolysis experiments.
DOI: 10.5286/isis.e.rb2010784
title: Inelastic Neutron Scattering Study to Investigate Giant Crystal-Electric-Field and Intermultiplet Splitting in CeRh3Si2

description: The orthorhombic CeRh3Si2 has been reported to exhibits multiple magnetic phase transitions. The zero-field heat capacity shows an antiferromagnetic order of the cerium magnetic moments at TN = 4.70 K and spin rearrangement at TSR = 4.48 K. In an applied field between 0.3 and 0.6 T it reveals three phase transitions below 4.8 K. Further the single crystal susceptibility exhibits strong anisotropy that has been explained by a giant crystal field splitting of the order of the intermultiplet splitting J=5/2 to J=7/2 which is usually of the order of 280 meV. There are very few Ce-based compounds exhibiting giant CEF splitting. We therefore propose an inelastic neutron scattering experiment on CeRh3Si2 using MERLIN in order to characterize the crystal-electric field (CEF) potential of the cerium ions and compare it to the already existing data of CeRh3B2.
DOI: 10.5286/isis.e.rb2010784-1
title: Inelastic Neutron Scattering Study to Investigate Giant Crystal-Electric-Field and Intermultiplet Splitting in CeRh3Si2

description: The orthorhombic CeRh3Si2 has been reported to exhibits multiple magnetic phase transitions. The zero-field heat capacity shows an antiferromagnetic order of the cerium magnetic moments at TN = 4.70 K and spin rearrangement at TSR = 4.48 K. In an applied field between 0.3 and 0.6 T it reveals three phase transitions below 4.8 K. Further the single crystal susceptibility exhibits strong anisotropy that has been explained by a giant crystal field splitting of the order of the intermultiplet splitting J=5/2 to J=7/2 which is usually of the order of 280 meV. There are very few Ce-based compounds exhibiting giant CEF splitting. We therefore propose an inelastic neutron scattering experiment on CeRh3Si2 using MERLIN in order to characterize the crystal-electric field (CEF) potential of the cerium ions and compare it to the already existing data of CeRh3B2.
DOI: 10.5286/isis.e.rb2010128
title: Interactions between Cell Mimicking Vesicles and de novo Ultrashort Peptide Amphiphiles: A Comparative SANS Study

description: In this work, we propose to exploit the unique capability of SANS to study the structural changes of the multi-component lipid bilayers surrounding small unilamellar vesicles (SUVs). SUVs of different lipid composition work well as models mimicking bacterial and mammalian cell membranes. Upon exposure to de novo designed ultrashort antimicrobial lipopeptides, SANS helps unravel how different lipopeptides bind to different lipid bilayers, providing useful indications about different mechanisms of action. We request 2 days on SANS2d time to exploit its wide Q range for resolving different sizes of structures and high flux for following dynamic structural changes.
DOI: 10.5286/isis.e.rb2010128-1
title: Interactions between Cell Mimicking Vesicles and de novo Ultrashort Peptide Amphiphiles: A Comparative SANS Study

description: In this work, we propose to exploit the unique capability of SANS to study the structural changes of the multi-component lipid bilayers surrounding small unilamellar vesicles (SUVs). SUVs of different lipid composition work well as models mimicking bacterial and mammalian cell membranes. Upon exposure to de novo designed ultrashort antimicrobial lipopeptides, SANS helps unravel how different lipopeptides bind to different lipid bilayers, providing useful indications about different mechanisms of action. We request 2 days on SANS2d time to exploit its wide Q range for resolving different sizes of structures and high flux for following dynamic structural changes.
DOI: 10.5286/isis.e.rb2010435
title: Magnetic phase diagram of the quasi-2D honeycomb antiferromagnet Na2Co2TeO6 single crystal

description: The layered compound Na2Co2TeO6 is a model honeycomb compound having a zigzag antiferromagnetic (AFM) ground state. Na2Co2TeO6 poses a rich magnetic phase diagram in the H-T plane. The zigzag antiferromagnet is predicted within the framework of (i) the frustrated J1-J2-J3 Heisenberg model and (ii) the Kitaev-Heisenberg model. Field induced exotic AFM star, zigzag star, and AFM vortex states are predicted for the Kitaev-Heisenberg model in contrast to canted zigzag state for the Heisenberg model. We propose single crystal neutron diffraction study on Na2Co2TeO6 as a function of H and T using the WISH diffractometer to determine the magnetic phase diagram and the spin model. The present study aims to have an experimental realization of the possible Kitaev-Heisenberg model (realized only in the compounds with 4d and 5d elements) in a compound with 3d7 (Co2+) ions.
DOI: 10.5286/isis.e.rb2010435-1
title: Magnetic phase diagram of the quasi-2D honeycomb antiferromagnet Na2Co2TeO6 single crystal

description: The layered compound Na2Co2TeO6 is a model honeycomb compound having a zigzag antiferromagnetic (AFM) ground state. Na2Co2TeO6 poses a rich magnetic phase diagram in the H-T plane. The zigzag antiferromagnet is predicted within the framework of (i) the frustrated J1-J2-J3 Heisenberg model and (ii) the Kitaev-Heisenberg model. Field induced exotic AFM star, zigzag star, and AFM vortex states are predicted for the Kitaev-Heisenberg model in contrast to canted zigzag state for the Heisenberg model. We propose single crystal neutron diffraction study on Na2Co2TeO6 as a function of H and T using the WISH diffractometer to determine the magnetic phase diagram and the spin model. The present study aims to have an experimental realization of the possible Kitaev-Heisenberg model (realized only in the compounds with 4d and 5d elements) in a compound with 3d7 (Co2+) ions.
DOI: 10.5286/isis.e.rb2068048
title: μSR study of the spin-spin correlations in spin gapped layered compound Na2Cu2TeO6

description: Na2Cu2TeO6 has been recognised as a spin-gapped layered compound and a Mott insulator. It has been proposed that non-orthogonal spin dimers lie on Cu2TeO6 layers, which piles up with alternative Na layers. The magnetic susceptibility χ shows a broad maximum at about Tmax = 160 K associated with a spin gap of Δ ∼ 250 K. The considerably large spin gap of about 250 K indicates the existence of a strong super-exchange coupling, which was also addressed by the 125Te NMR studies. The Muon-spin rotation/relaxation (μSR) study is one of the powerful microscopic tools, which can probe both the statis and dynamic characteristics of spins. Till now, the μSR studies have not been attempted to address the low dimensional short range ordering.We therefore propose to investigate the temperature dependence of μSR on Na2Cu2TeO6 both in zero magnetic field and in presence of magnetic field.
DOI: 10.5286/isis.e.rb2068048-1
title: μSR study of the spin-spin correlations in spin gapped layered compound Na2Cu2TeO6

description: Na2Cu2TeO6 has been recognised as a spin-gapped layered compound and a Mott insulator. It has been proposed that non-orthogonal spin dimers lie on Cu2TeO6 layers, which piles up with alternative Na layers. The magnetic susceptibility χ shows a broad maximum at about Tmax = 160 K associated with a spin gap of Δ ∼ 250 K. The considerably large spin gap of about 250 K indicates the existence of a strong super-exchange coupling, which was also addressed by the 125Te NMR studies. The Muon-spin rotation/relaxation (μSR) study is one of the powerful microscopic tools, which can probe both the statis and dynamic characteristics of spins. Till now, the μSR studies have not been attempted to address the low dimensional short range ordering.We therefore propose to investigate the temperature dependence of μSR on Na2Cu2TeO6 both in zero magnetic field and in presence of magnetic field.
DOI: 10.5286/isis.e.rb2010342
title: Materials for Equilibrium busting Thermodynamically-Reversible Memory Reactors

description: We have recently reported the first thermodynamically reversible chemical reactor – the memory reactor – which allows one to perform reversible chemical reactions beyond the normal limits imposed by chemical equilibrium. In one application the reactor can produce pure streams of hydrogen from the water gas shift reaction. The performance of the reactor relies on a gradual change in oxygen content of a so-called oxygen carrier material (OCM), for which we use a non-stoichiometric perovskite whose composition can vary between ABO3 and ABO2.75 as the reactor operates. Total scattering studies on POLARIS will help us understand the key changes in the local structure of the OCM during reactor operation, help us understand the operating limitations of different OCM materials, allow us to design better OCMs and to optimise the reactor's performance.
DOI: 10.5286/isis.e.rb2010342-1
title: Materials for Equilibrium busting Thermodynamically-Reversible Memory Reactors

description: We have recently reported the first thermodynamically reversible chemical reactor – the memory reactor – which allows one to perform reversible chemical reactions beyond the normal limits imposed by chemical equilibrium. In one application the reactor can produce pure streams of hydrogen from the water gas shift reaction. The performance of the reactor relies on a gradual change in oxygen content of a so-called oxygen carrier material (OCM), for which we use a non-stoichiometric perovskite whose composition can vary between ABO3 and ABO2.75 as the reactor operates. Total scattering studies on POLARIS will help us understand the key changes in the local structure of the OCM during reactor operation, help us understand the operating limitations of different OCM materials, allow us to design better OCMs and to optimise the reactor's performance.