cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.5286/isis.e.rb1620402
title: Perfluorocarbon-loaded polymeric nanoparticles with multiple perfluorocarbon domains for clinical and in vivo imaging

description: Ultrasound is a very attractive and patient-friendly imaging technique, as it is easy to use, fast and non-invasive. Nevertheless, its use is severely limited by the low stability of current contrast agents, as they contain gaseous or vaporizing phase. We developed perfluorocarbon-loaded poly(lactide-co-glycolide) nanoparticles (NPs), which are suitable for long-term imaging, in a time-scale of days. However, the mechanism of contrast generation is completely unclear. The internal structure of our NPs appears completely different from currently reported perfluorocarbon-loaded colloids. Thus, elucidating the internal structure of these nanoparticles is a key to describe the mechanism of acoustic contrast generation. As SANS has been successfully applied by other researchers to study fluorinated colloids, we propose SANS to investigate the structure of our NPs.
DOI: 10.5286/isis.e.rb1670544
title: Muon sites study on organic-inorganic hybrid materials
DOI: 10.5286/isis.e.rb1700011
title: Muon spin relaxation investigation of hybrid perovskite solar cell materials
DOI: 10.5286/isis.e.rb1700050
title: Fragile to strong transition in concentrated sorbitol-water solutions

description: In a recent paper [J. Phys. Chem. B, 2016, 120 (29), pp 72897296] we have put forward the idea that water in concentrated (70 wt%) sorbitol-water solutions becomes confined by the surrounding sorbitol matrix. From 298 K to 210 K there was a marked increase in the tetrahedrality parameter of the solution water, but there was no indication of whether this change was gradual or was at a particular temperature. At the same time, THz spectroscopy by one of us on the same system indicates a possible fragile-strong transition in the water at around 250 K. Similar fragile to strong transitions have been claimed to be observed in water confined in porous silica, but so far have remained unconfirmed. The idea of the present experiment is to see if the change in tetrahedrality parameter between 210 K and 273 at this concentration is sharp or continuous, by taking a series of scans in 10 K steps.
DOI: 10.5286/isis.e.rb1710208
title: Neutron cross sections and mechanical properties of boron nitrate doped polymer composites

description: Hexagonal boron nitride (hBN) is a layered material possessing extraordinary physical properties such as ultrahigh chemical stability, high electronic bandgap (about 6.5 eV), good thermal conductivity and negative electron affinity. Also known as white graphite, due to the similar (hexagonal) crystal structure, hBN powder provides excellent lubricating properties being commonly used in industrial applications. In the last years, hBN has emerged as an important material for deep ultraviolet photonics and as well as solid-state neutron detectors.hBN has traditionally been considered as a material of choice in thermal-management applications and dispersed in polyimide and epoxy matrix to give nanocomposite films with superior thermal transport performance without degrading mechanical properties (up to 15 vol%).
DOI: 10.5286/isis.e.rb1710262
title: The use of lipid sponge-like nanoparticles as carriers for macromolecules and their interaction with proteins

description: Conventional ways to administer and deliver drugs have reached its limitations. These methods can be still used for small and simple molecules. However, new carriers have to be developed for active compounds that are large, like proteins, or that cannot be dissolved in water. One of the proposed methods is the use of lipid based nanoparticles. Lipids are very abundant in the nature; we eat them, we process or digest them and even our cell membranes are formed by lipids. They have the advantage that can organize themselves in different structures depending on the nature of the lipid and its environment. Therefore, these particles are a potential tool for the encapsulation and control release of macromolecules. In addition, lipid based nanoparticles can also be of benefit in the food industry. For example, they can be used to control the delivery of enzymes employed during food processing.
DOI: 10.5286/isis.e.rb1710282
title: Structural insights into crude oil asphaltenes: A multi-parametric SANS/WANS study

description: Asphaltenes are a complex and problematic fraction of crude oil that can precipitate, alter wettability and stabilise unwanted oil-in-water emulsions. Asphaltene molecules are generally thought to consist of one (or more) aromatic cores with alkyl side chains. When the asphaltenes precipitate from crude oil they are thought to do so by stacking of the aromatic cores. This can be seen in small angle scattering due to aggregation of carbon rich aromatic cores and in the wide angle scattering by a broad peak similar to that seen in graphite. However key questions remain, such as the proportion of asphaltenes that form these stacked aromatic cores. The prevailing model for asphaltene structure is based on the majority of asphaltene molecules aggregating through stacking, initial results have shown this may not be the case, we will use NIMROD to measure SANS/WANS to study this further.
DOI: 10.5286/isis.e.rb1710363
title: Study of Structural Transitions in Tellurite Glasses by Insitu High Pressure Neutron Diffraction

description: Tellurite glasses have an interesting structural feature that Te ions have two coordinations of 3 and 4 with oxygen in the glass network. TeO2 is a conditional glass former and forms glass at very high melt-quenching rates, on adding metal oxides it forms glasses easily at low quenching rates. While the structural modifications in the tellurite network with changes in composition are well studied, the effects of thermodynamic parameters i.e. pressure and temperature on the short range structural features like Te-O speciation, bond lengths and bond angle distributions remain unexplored. This proposal aims to study insitu the effects of high pressures on the short range and medium range order in barium tellurite glasses by neutron diffraction. The studies will provide new insights on pressure induced transformations in glass structure and whether these changes are reversible or permanent.
DOI: 10.5286/isis.e.rb1710369
title: Molecular and framework dynamics in CH3NH3PbCl3

description: We propose to use MARI to measure the molecular and framework dynamics in CH3NH3PbCl3 which has become of interest in the context of efficient photovoltaics.    CH3NH3PbCl3 is different from other organic-inorganic materials as it lacks a structural phase transition to a tetragonal unit cell.  The point of this experiment is compare the lattice dynamics to CH3NH3PbBr3 previously measured.  We will also search for a soft mode at low temperature.
DOI: 10.5286/isis.e.rb1710498
title: Tuning Emergent Magnetisation Dynamics in Interconnected Nanomagnets

description: Access to OFFSPEC is requested to investigate emergent magnetisation dynamics in ensembles of interconnected ring-shaped nanowires. When these ensembles are subjected to rotating magnetic fields they will host dynamic populations of domain walls, the equilibrium number and spatial distribution of which will develop emergently from simple rules related to the geometry of the ensemble and strength of inter-domain wall interactions. We will use polarized neutron scattering to gain understanding of these emergent dynamics, thus making a critical step towards harnessing them in future unconventional computing platforms.
DOI: 10.5286/isis.e.rb1720073
title: Bi0.775Ln0.225O1.5 (Ln = La, Dy) Oxide Ion Conductors:  Local Structure, Complex Superstructures and Structural Phase Transitions

description: Bismuth(III) containing oxides display numerous interesting properties, such as ionic conductivity, ferroelectricity, nonlinear optical properties, catalytic activity  and superconductivity. The driving force for these properties is found in their structural features, often associated with the stereochemical activity of the Bi(III) lone pair. Most Bi2O3related oxide ion conductors which can be prepared by chemical doping fall into two categories: fluorite-type materials which retain the cubic structure of d-Bi2O3 or fluorite-related layered rhombohedral materials. The objectives of the experiments are:To determine the local structures of Bi0.775Ln0.225O1.5 (Ln = La, Dy) using a combination of neutron and X-ray total scattering and elucidate the Bi/Ln cation ordering and its role in superstructure formation,To determine the oxygen sublattice arrangement in the material.
DOI: 10.5286/isis.e.rb1720414
title: In-situ reaction of lithium amide or imide with manganese(IV) oxide

description: We request 3 days beam time on POLARIS for in-situ powder diffraction studies of the reactions of lithium amide or lithium imide with manganese(IV) oxide under flowing argon or ammonia. This novel synthesis method has recently produced the new ternary lithium-manganese oxide, Li10Mn4O9. POLARIS is the beamline of choice to determine the nature of these materials as they are synthesised, since it has good resolution and also has an in-situ gas flow cell with bespoke shielding. The knowledge gained will be used to inform the direction of novel syntheses with the hope of generating new materials relevant for energy storage applications.
DOI: 10.5286/isis.e.rb1720457
title: Characterising Early Iron Age Indian Iron Smelting Technology: neutron analysis

description: Recent archaeological research, supported by radiocarbon dates, indicates that iron production in India can now be dated to the earlier part of the 2nd millennium BC, pre-dating the Bronze-Iron transition in Anatolia and the Eastern Mediterranean. Conventional bulk chemical analysis of silicates (e.g smelting slag, ore, furnace lining) and metal artefacts is destructive. We will use neutron and muon instruments at ISIS to obtain genuine bulk compositions, without dissolving or crushing-up samples, or cutting metallographic sections from the irreplaceable archaeological material. We propose to use negative muon analysis to do non-destructive bulk chemical analysis of the earliest-dated smelting slag, furnace lining, and ore fragments from archaeological sites in Uttar Pradesh and Madhya Pradesh, India. We request 9 days of muon beamtime, and 5 days of INES beamtime, to carry out the work.
DOI: 10.5286/isis.e.rb1768046
title: Probing the ground state and spin dynamics of Quantum spin system CuAl2O4 by Muon Spin Relaxation/Rotation experiments

description: The normal spinel oxide CuAl2O4 has Cu in a 2+ state with quantum spin, S = ½ and shows all the hallmark properties of a quantum spin glass that include a frequency dependent cusp at ~2 K in the ac magnetic susceptibility, the right shift of this 2 K peak in zero field heat capacity in higher applied magnetic fields and logarithmic relaxation rate of magnetization. In addition, there is no evidence of a long range order in the powder neutron diffraction data down to ~0.4 K. A large frustration parameter is found from the dc magnetization data. Although Cu2+ is a Jahn-Teller ion, CuAl2O4 does not undergo any structural distortion down to 0.4 K. Therefore, CuAl2O4 could be a rare example of a frustrated quantum spin glass with orbital liquid state for ground state. In this work, we will study the slow spin dynamics by carrying out muSR experiments and ascertain the glass-like ground state.
DOI: 10.5286/isis.e.rb610232
title: Q-dependence of the single particle motion in a molten alkali halide

description: An inelastic X-ray investigation on the collective inelastic dynamics of molten NaCl revealed the remarkable result that the acoustic-like dynamics is similar to the dispersion of liquid sodium. One interpretation could be that the cation movement is decoupled from the anion "background" at high frequencies or equivalent  at short wavelengths. This anomalous behaviour should be reflected in the single particle motion of the cations. The aim of the experiment is to determine the Q-dependent broadening of the quasielastic line steming from the sodium diffusion in molten NaBr to confirm the anomalous behaviour of the cations with rising momentum transfer.
DOI: 10.5286/isis.e.rb13136
title: Empty Vycor T=5 K      jaws: 50horx35vert 750meV A600  nim 50Hz
DOI: 10.5286/isis.e.rb1510107
title: Monitoring the changes in the local environment of titanium in modified network silicate glasses by in-situ diffraction measurements with is

description: In this experiment we aim to evaluate the structure of titanium-rich glasses as they are compressed. In a previous experiment we have collected data for K2TiSi2O7 glasses with different titanium isotopes and we wish to continue this wok by studying a magnesium alumino-silicate glass which has a more geologically relevant composition. The motive for this is the complex role that titanium has in many primitive liquid compositions, notably on the moon and we aim to shed light on the anomalous compressibility of titanium-bearing systems. We will collect data on two glasses with different titanium isotopes to pressures up to 8GPa. Isotopic substitution allows the extraction of the partial contribution of titanium and unequivocal determination of the change in local environment around titanium atoms.
DOI: 10.5286/isis.e.rb1510302
title: Pressure-Tuning Interactions in Spin-Crossover Metal-Organic Frameworks

description: The magnetism of spin-crossover (SCO) materials containing Fe(II) can be switched by changing conditions. The low-spin state existing at low temperature or high pressure can be excited to the high-spin state at higher temperature or lower pressure. In SCO materials based on frameworks the strong framework bonds propagate spin transitions at one site through the whole framework. In addition the material properties depend on the presence of different guest molecules in the framework interstices. The building blocks of the framework and the guests can be chemically modified generating almost infinite design possibilities, but understanding the relationship between structure and properties is critical. In this study we will vary temperature, pressure, framework components and guest content to provide a comprehensive survey of structure-property relationship in two framework SCO materials.
DOI: 10.5286/isis.e.rb1510360
title: Condensed Spin Waves in the Rock Salt Metal Oxides

description: The late first row transition metal monoxides are the canonical antiferromagnets. Their magnetic structures were first determined many decades ago but contemporary studies have unearthed a wealth of unexpected physics in these oxides. Our total scattering studies have shown they adopt more complex magnetic structures, suggestive of magnetic modulations, revealing that previous studies painted far too simple a picture of their magnetic ordering. Since these are the fundamental compounds from which much of our knowledge of magnetism is built a detailed understanding of their antiferromagnetic states is vital. Preliminary studies of MnO using the unique high resolution of WISH, confirm the presence of magnetic modulations and we are in a unique position to extend this to a precise determination of the magnetic structures of NiO and CoO, to resolve questions regarding these canonical oxides.
DOI: 10.5286/isis.e.rb1510372
title: Elucidating the magnetic nature of alpha-RuCl3 - a rediscovered honeycomb system

description: Materials with layered honeycomb structures have been subject to a strenuous research effort in the past couple of years in an effort to find materials that exemplify the exactly soluble Kitaev model, with its spin liquid ground state. alpha-RuCl3 has many of the properties needed by the Kitaev model but, like most other candidate materials, shows magnetic order. Many interesting ordered states have been found in the other candidate materials but, despite decades of study, the nature of the magnetic ordering of alpha-RuCl3 is yet to be resolved. Using a two-pronged assault of muon spin relaxation and resonant x-ray scattering we aim to determine the nature of the magnetic ground state.
DOI: 10.5286/isis.e.rb1510432
title: Magnetic ordering in the layered honeycomb alpha-RuCl3

description: This proposal is part of our research programme to explore novel phases stabilized by the combined effect of spin-orbit interaction and electron correlations. Here we aim to probe the magnetic order in the insulating layered honeycomb magnet alpha-RuCl3. The crystal structure is very close to ideal conditions (near cubic crystal field at Ru sites and near 90 deg Ru-Cl-Ru bonds) proposed theoretically to realize a canonical quantum frustrated system, the Kitaev model on the honeycomb lattice. Here all nearest neighbour bonds are of Ising character, but the three bonds that meet at each site have orthogonal Ising directions, leading to strong frustration effects that could stabilize novel ordered phases. This proposal builds upon our very successful study of Kitaev physics in the iridates Li2IrO3 with three-dimensional honeycomb structures (on WISH and I16@Diamond).
DOI: 10.5286/isis.e.rb1510617
title: High-Pressure Study of the Crystal Structure of Guanidine

description: Guanidine, (NH2)2C=NH, was first synthesised more than 150 years ago and is the prototype of a whole class of compounds which have received considerable attention due to their widespread use in synthetic chemistry, biochemistry and technological applications. The crystal structure of guanidine itself, however, has only been determined within the past five years. Diffraction studies revealed that guanidine crystallises in a large intricate orthorhombic structure containing two independent molecules and sixteen molecules in the unit cell. The main aims of the proposed high-pressure study of deuterated guanidine will be to: i) investigate the phase transition behaviour up to 8 GPa at room temperature, ii) determine the structures of any new phases that may be observed, and iii) establish the variation with pressure of the hydrogen bonding networks within the observed phases.
DOI: 10.5286/isis.e.rb1510621
title: High-Pressure Investigation of the Ferroelectric ND4IO3

description: We propose a high-pressure neutron powder diffraction study of the crystal structure of deuterated ammonium iodate, ND4IO3, which is known to undergo a ferroelectric phase transition at 368 K at ambient pressure. In addition to the covalent bonds within the IO3- and ND4+ ions, the secondary bonds consists of short O...I halogen bonds and N-H¿O hydrogen bonds. The proposed two-part experiment will collect high-quality neutron powder diffraction data at room-temperature up to 8 GPa and will also investigate the ferroelectric phase transition behaviour at 395 K for pressures up to 5 GPa. The main aims of this neutron study will be to: i) determine the structure pressure dependence of ammonium iodate at room temperature, ii) structurally characterise the ferroelectric transition region of p-T space, and iii) determine the structures of any previously unknown phases which we may encounter.
DOI: 10.5286/isis.e.rb1510627
title: The role of hydrogen atoms in the ferroelectric transition of [NH4][Zn(HCOO)3].

description: This proposal aims at better understanding the role of the disordered NH4+ ions in driving the ferroelectric transition in [NH4][Zn(HCOO)3] and that of hydrogen bonding in stabilizing the ferroelectric phase.In order to perform a full characterization, we propose to study the structure of the ammonium-zinc formate as a function of temperature. The ferroelectric transition occurs at 192K, therefore a measurement at 300K will elucidate the paraelectric phase. Additional data at 175, 100 and 20K will provide information on the development of the ferroelectric distortion mode and on the order parameter. In addition, the analysis of the temperature dependence of the atomic displacement parameters between 20 and 175K will give information about the low frequency normal modes contributing to the structural phase transition.
DOI: 10.5286/isis.e.rb1520283
title: Spin excitations in RbFe2F6 and CsFe2F6  A possible S=5/2 Kagome lattice?

description: Geometrically frustrated spin systems are important owing to the fact that the geometry often suppresses conventional mean field ground states in favor of more unconventional phases of matter.  Examples include spin ices, spin-liquids, and spin nematic phases. Arguably the simplest geometrically frustrated lattice is the case of a two dimensional triangular lattice. We propose to measure the spin excitations in a new family of frustrated magnets.
DOI: 10.5286/isis.e.rb1600034
title: Disordered H2O ice II  a possible new ice phase
DOI: 10.15156/bio/sh0964062.09fu
title: SH0964062.09FU

description: UNITE provides a unified way for delimiting, identifying, communicating, and working with DNA-based Species Hypotheses (SH). All fungal ITS sequences in the international nucleotide sequence databases are clustered to approximately the species level by applying a set of dynamic distance values (<0.5 - 3.0%). All species hypotheses are given a unique, stable name in the form of a DOI, and their taxonomic and ecological annotations are verified through distributed, web-based third-party annotation efforts. SHs are connected to a taxon name and its classification as far as possible (phylum, class, order, etc.) by taking into account identifications for all sequences in the SH. An automatically or manually designated sequence is chosen to represent each such SH. These sequences are released (https://unite.ut.ee/repository.php) for use by the scientific community in, for example, local sequence similarity searches and next-generation sequencing analysis pipelines. The system and the data are updated automatically as the number of public fungal ITS sequences grows.
DOI: 10.15156/bio/sh0964063.09fu
title: SH0964063.09FU

description: UNITE provides a unified way for delimiting, identifying, communicating, and working with DNA-based Species Hypotheses (SH). All fungal ITS sequences in the international nucleotide sequence databases are clustered to approximately the species level by applying a set of dynamic distance values (<0.5 - 3.0%). All species hypotheses are given a unique, stable name in the form of a DOI, and their taxonomic and ecological annotations are verified through distributed, web-based third-party annotation efforts. SHs are connected to a taxon name and its classification as far as possible (phylum, class, order, etc.) by taking into account identifications for all sequences in the SH. An automatically or manually designated sequence is chosen to represent each such SH. These sequences are released (https://unite.ut.ee/repository.php) for use by the scientific community in, for example, local sequence similarity searches and next-generation sequencing analysis pipelines. The system and the data are updated automatically as the number of public fungal ITS sequences grows.
DOI: 10.15156/bio/sh0964064.09fu
title: SH0964064.09FU

description: UNITE provides a unified way for delimiting, identifying, communicating, and working with DNA-based Species Hypotheses (SH). All fungal ITS sequences in the international nucleotide sequence databases are clustered to approximately the species level by applying a set of dynamic distance values (<0.5 - 3.0%). All species hypotheses are given a unique, stable name in the form of a DOI, and their taxonomic and ecological annotations are verified through distributed, web-based third-party annotation efforts. SHs are connected to a taxon name and its classification as far as possible (phylum, class, order, etc.) by taking into account identifications for all sequences in the SH. An automatically or manually designated sequence is chosen to represent each such SH. These sequences are released (https://unite.ut.ee/repository.php) for use by the scientific community in, for example, local sequence similarity searches and next-generation sequencing analysis pipelines. The system and the data are updated automatically as the number of public fungal ITS sequences grows.