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We have designed and realized a temperature and pressure controlled cell for Neutron Reflectometry (NR) and Small Angle Neutron Scattering (SANS) that is compatible with simultaneous optical transmission and resistivity measurements. The cell can accommodate samples up to 102 mm (4 inch) in diameter, can be pressurized from vacuum up to 10 bar gas pressure and the sample temperature can be controlled up to 350°C. The four single crystal quartz windows ensure both a good neutron and optical transmission and hence can be used in combination with in-situ optical transmission measurements. We present the cell and illustrate its performance with a series of neutron reflectometry experiments performed on Ta based thin films under a hydrogen containing atmosphere. [ABSTRACT FROM AUTHOR]

The use of block copolymers to compatibilize immiscible plastics is an important strategy for upcycling municipal plastic wastes. Multiblock copolymers (MBCPs) have been proven to be more effective compatibilizers than di- and tri-block copolymers. Herein, we probe the interface structure of an effective multiblock copolymer compatibilizer and compare that with an ineffective triblock copolymer (TBCP). The interface activity of the compatibilizers is understood through a combination of small-angle neutron and x-ray scatterings (SANS and SAXS), by using deuterated homopolymer matrix and protonated compatibilizers. SANS analysis suggests that the MBCP forms a thicker interface layer (7-9 nm) than the TBCP (0-4 nm). In addition, SANS data seems to point to a stronger tendency for the MBCP to locate at the interface. Both factors contribute to its effectiveness at compatibilizing immiscible homopolymers. [ABSTRACT FROM AUTHOR]

Utilizing small angle neutron scattering techniques on organic shales, this study presents an innovative approach for characterizing the status of oil occurrence, and new insights into pore scale assessment through scattering vector-pore size relationship. The results indicate the successful identification of different shale oil occurrence status, before and after solvent extraction of residual oil for four shale samples with different contents of total organic carbon. In addition, coupled with density distribution analyses, the work demonstrates that shale samples with lower total organic carbon contents typically signify a smaller radius of gyration with better oil mobility, which indicates a greater wave oscillation with a larger pore size to be estimated from the scattering vector. This work also elucidates the notable scenarios of an increasing pore size could correspond to a decreasing radius of gyration caused by mass density redistribution. For polydisperse systems, this research illustrates the variations in pore volumetric ratio impact the scattering intensity, whereas pore scale changes affect the oscillation pattern. This novel research of analyzing mass density distribution and pore scale information in real space is also suitable for other porous media systems. [ABSTRACT FROM AUTHOR]

The microstructure of wormlike micelles (WLM) directly affects the rheological properties of their solutions. Investigating the structure–property relationships of WLM has long been a popular topic for researchers who have developed theoretical and empirical models to describe their viscoelastic behavior. All these models rely on a collection of characteristic "length" parameters that are often difficult to estimate using relatively simple rheological tests. In particular, the micelle stiffness, as described by the persistence length, can be difficult to measure experimentally, while being very impactful on the bulk rheology of WLM solutions. Here, an array of inorganic salts (NaCl, LiCl, MgCl2, NaBr, NaI, and Na2SO4) have been used to induce wormlike micelle formation in an aqueous solution of the surfactant sodium lauryl ether sulfate. Ion dissociation/association with the surfactant head groups and the hydrogen bond network of the water alters the effective stiffness of the micelles, allowing for an estimation of the stiffness using three different methods: (1) small angle neutron scattering (SANS) measurements, (2) oscillatory rheological measurements, and (3) steady rheological measurements with a thermodynamic packing parameter model. Each of these methods are then compared and shown to be consistent with each other for the micelle solutions tested. The consistency of the results across all the measurements suggests that the approach used in this study, which estimates micelle parameters using steady shear rheology and a thermodynamic model, could provide a simpler and more accessible method for estimating micelle parameters in a wide range of surfactant systems. [ABSTRACT FROM AUTHOR]

In this work, the nanostructure of oxide dispersion-strengthened steels was studied by small-angle neutron scattering (SANS), transmission electron microscopy (TEM), and atom probe tomography (APT). The steels under study have different alloying systems differing in their contents of Cr, V, Ti, Al, and Zr. The methods of local analysis of TEM and APT revealed a significant number of nanosized oxide particles and clusters. Their sizes, number densities, and compositions were determined. A calculation of hardness from SANS data collected without an external magnetic field, or under a 1.1 T field, showed good agreement with the microhardness of the materials. The importance of taking into account two types of inclusions (oxides and clusters) and both nuclear and magnetic scattering was shown by the analysis of the scattering data. [ABSTRACT FROM AUTHOR]

Despite being the major cause of safety and performance issues in lithium metal batteries, experimental difficulties in quantifying directly the morphology of lithium deposited at electrode surfaces have meant that the mechanism of metallic lithium growth within batteries remains elusive. This study demonstrates that quantitative detail about the morphology of metallic lithium within batteries can be derived non‐destructively and directly using in situ ultra‐small and small‐angle neutron scattering. This information is obtained over a large electrode area in cells where lithium deposition processes are typical of real‐world applications. Complex variations of surface area and interfacial distances 1–10 µm and 100–300 nm are revealed in size that are influenced by current density and cell cycling history, providing valuable insight into the growth of metallic lithium features detrimental to battery performance. Such quantitative insight into the process of lithium growth is required for the development of safer high‐performance lithium metal batteries. [ABSTRACT FROM AUTHOR]

Magnetite and gallium substituted cuboferrites with a composition of GaxFe3−xO4 (0 ≤ x ≤ 1.4) were fabricated by thermal decomposition from acetylacetonate salts. The effect of Ga3+ cation substitution on the structural and thermomagnetic behavior of 4–12 nm sized core-shell particles was explored by X-ray and neutron diffraction, small angle neutron scattering, transmission electron microscopy, Mössbauer spectroscopy, and calorimetric measurements. Superparamagnetic (SPM) behavior and thermal capacity against increasing gallium concentration in nanoferrites were revealed. The highest heat capacity typical for Fe3O4@Ga0.6Fe2.4O4 and Ga0.6Fe2.4O4@Fe3O4 is accompanied by a slight stimulation of fibroblast culture growth and inhibition of HeLa cell growth. The observed effect is concentration dependent in the range of 0.01–0.1 mg/mL and particles of Ga0.6Fe2.4O4@Fe3O4 design have a greater effect on cells. Observed magnetic heat properties, as well as interactions with tumor and healthy cells, provide a basis for further biomedical research to use the proposed nanoparticle systems in cancer thermotherapy (magnetic hyperthermia). [ABSTRACT FROM AUTHOR]

Small‐Angle Scattering (SAS) techniques are essential tools for the characterization of catalysts before, during and after catalytic reactions. Either based on X‐Rays (SAXS) or neutrons (SANS), they provide unique structural information that helps to understand catalytic processes at the nanoscale level, allowing a rational improvement of the catalysts design. In this review, we present the key aspects involved in the use of these techniques in the catalysis field. Firstly, we introduce some of the fundamentals of the techniques and describe their main features and their impact in the catalyst design. Then, we analyze key examples of the use of SAS to study catalysts' structure through ex situ analysis, focusing on examples involving different porous materials and metallic nanoparticles. Afterwards, we discuss in situ and operando approaches for studying catalytical processes monitored using SAS. Finally, we present perspectives and challenges for the future use of SAS in the catalysis field. [ABSTRACT FROM AUTHOR]

Here, we describe the behavior of mixtures of stearic acid (SA) and its hydroxylated counterpart 12-hydroxystearic acid (12-HSA) in aqueous mixtures at room temperature as a function of the 12-HSA/SA mole ratio R. The morphologies of the self-assembled aggregates are obtained through a multi-structural approach that combines confocal and cryo-TEM microscopies with small-angle neutron scattering (SANS) and wide-angle X-ray scattering (WAXS) measurements, coupled with rheology measurements. Fatty acids are solubilized by an excess of ethanolamine counterions, so that their heads are negatively charged. A clear trend towards partitioning between the two types of fatty acids is observed, presumably driven by the favorable formation of a H-bond network between hydroxyl OH function on the 12th carbon. For all R, the self-assembled structures are locally lamellar, with bilayers composed of crystallized and strongly interdigitated fatty acids. At high R, multilamellar tubes are formed. The doping via a low amount of SA molecules slightly modifies the dimensions of the tubes and decreases the bilayer rigidity. The solutions have a gel-like behavior. At intermediate R, tubes coexist in solution with helical ribbons. At low R, local partitioning also occurs, and the architecture of the self-assemblies associates the two morphologies of the pure fatty acids systems: they are faceted objects with planar domains enriched in SA molecules, capped with curved domains enriched in 12-HSA molecules. The rigidity of the bilayers is strongly increased, as well their storage modulus. The solutions remain, however, viscous fluids in this regime. [ABSTRACT FROM AUTHOR]

X‐ray diffraction and small‐angle neutron scattering were used to identify the naturally occurring hormone auxin in Madeira vine. Two kinds of auxins belonging to indole‐3‐acetic acid (IAA, C10H9NO2) and 4‐chloroindole‐3‐acetic acid (4‐Cl‐IAA, C10H8ClNO2) have been found. The appearance of well‐defined x‐ray diffraction peaks from the IAA as well as from the 4‐Cl‐IAA structures shows that the IAA and 4‐Cl‐IAA molecules that are produced at the shoot apex crystallize into periodic arrangements, rather than stay in molecular forms, upon transport downward through in stem. Small angle neutron scattering spectra reveal a progressive increase in the length of crystallized IAA and 4‐Cl‐IAA on transported downward from the shoot apex to the stem, reaching 59 nm in length in the area 8–9 cm below the shoot apex. A portion of IAA loses their carboxyl group COOH becoming inactive in stimulating cell growth, which slows down the growth in an aged stem. [ABSTRACT FROM AUTHOR]

Three mesogenic compounds: n-cyano-3-fluorophenyl 4-butylbenzoates (n = 4,6,8), abbreviated 4CFPB, 6CFPB, and 8CFPB contained in mesoporous Anodic Aluminium Oxide (AAO) membranes were subjected to Small Angle Neutron Scattering measurements with the aim to test the feasibility of SANS experiment as a means of detecting a boundary layer and estimating its thickness. This proved successful for 4CFB and 6CFPB in 18 nm pores, and indicative in 35 nm pores. The thickness of the boundary layer was estimated by core-shell SANS models at ca. 23–26 Å (2.3–2.6 nm). [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas & Oil is the property of Editorial Department of Natural Gas & Oil and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Amyloid-ß peptide interactions with model lipid membranes have been studied by means of small angle neutron scattering and molecular dynamics simulations. These interactions had been indicated recently as an origin of the membrane structure reorganizations between spherical small unilamellar vesicles and planar bicelle-like structures. In present work, we investigate the influence of charge on the peptide-triggered morphological changes by introducing the anionic lipid DMPS to the underlying DMPC membrane. Changes to the membrane thickness and the overall membrane structure with and without Aß25-35 incorporated have been investigated over a wide range of temperatures. Our results document the previously reported morphological reformations between bicelle-like structures present in gel phase and small unilamellar vesicles present in fluid phase to be independent from the charge existence in the system. [ABSTRACT FROM AUTHOR]

This structural study exploits the possibility to use modular protein deuteration to facilitate the study of ubiquitin signalling, transfer, and modification. A protein conjugation reaction is used to combine protonated E2 enzyme with deuterated ubiquitin for small angle X-ray and neutron scattering with neutron contrast variation. The combined biomolecules stay as a monodisperse system during data collection in both protonated and deuterated buffers indicating long stability of the E2–Ub conjugate. With multiphase ab initio shape restoration and rigid body modelling, we reconstructed the shape of a E2–Ub-conjugated complex of UBE2D1 linked to ubiquitin via an isopeptide bond. Solution X-ray and neutron scattering data for this E2–Ub conjugate in the absence of E3 jointly indicate an ensemble of open and backbent states, with a preference for the latter in solution. The approach of combining protonated and labelled proteins can be used for solution studies to assess localization and movement of ubiquitin and could be widely applied to modular Ub systems in general. [ABSTRACT FROM AUTHOR]

Magnesium doped Amorphous Calcium Carbonate was synthesised from precursor solutions containing varying amounts of calcium, magnesium, H2O and D2O. The Mg/Ca ratio in the resultant Amorphous Calcium Carbonate was found to vary linearly with the Mg/Ca ratio in the precursor solution. All samples crystallised as aragonite. No Mg was found in the final aragonite crystals. Changes in the Mg to Ca ratio were found to only marginally effect nucleation rates but strongly effect crystal growth rates. These results are consistent with a dissolution-reprecipitation model for aragonite formation via an Amorphous Calcium Carbonate intermediate. [ABSTRACT FROM AUTHOR]

This study describes thermo‐rheological properties of branched copolymer surfactants (BCSs) stabilizing oil‐in‐water emulsions to generate materials exhibiting temperature‐dependent gelation with the ability to solubilize a broad range of molecules. Four poly(N‐isopropylacrylamide‐ran‐poly(ethylene glycol) methacrylate) (poly(NIPAM‐ran‐PEGMA)) BCSs with varying molecular weight (Mn), 4.7; 7.0; 7.8 and 9.0 kg mol−1, are investigated via oscillatory shear rheology, small angle neutron scattering (SANS), and neutron reflectivity (NR). Rheological thermoscans show that emulsions stabilized by the BCS with the lowest Mn (4.7 kg mol−1) are thermo‐thinning, while with the other BCSs the emulsions display a thermo‐thickening behavior. Emulsions stabilized with the BCS with Mn = 7.8 kg mol−1 form gels within a precise temperature window depending on BCS concentration. Small angle neutron scattering data analysis suggests that the BCS is present in two forms in equilibrium, small aggregates dispersed in the bulk water and an adsorbed polymeric layer at the oil/water interface. Changes in dimensions of these structures with temperature correlate with the macroscopic thermo‐thinning/thermo‐thickening behavior observed. Neutron reflectivity is conducted at the oil/water interface to allow further elucidation of BCS behavior in these systems. [ABSTRACT FROM AUTHOR]

Studies in spin dynamics of disordered media and multiple ultra-small angle neutron scattering are considered. The experiments were carried out on unique installations designed in ITEP laboratory of neutron physics: beta-NMR spectrometer and universal neutron diffractometer. The main attention is paid to random walks in disordered systems and ultra-small angle neutron scattering (USANS) on objects with space correlations in positions of scatterers. Synthesis of concentration expansion, semi-phenomenological theory and numerical simulations produced satisfactory description of the nuclear polarization transfer within disordered 8Li–6Li spin subsystem in LiF single crystal. The theory of USANS starts from eikonal approximation for the scattering amplitude, which (a) reproduces the phenomenological Moliere–Bethe theory for the observable neutron angular distributions for uncorrelated random positions of scatterers, and (b) gives a possibility to take into account their spatial correlations. [ABSTRACT FROM AUTHOR]

Lipid structural diversity strongly affects biomembrane chemico-physical and structural properties in addition to membrane-associated events. At high concentrations, cholesterol increases membrane order and rigidity, while polyunsaturated lipids are reported to increase disorder and flexibility. How these different tendencies balance in composite bilayers is still controversial. In this study, electron paramagnetic resonance spectroscopy, small angle neutron scattering, and neutron reflectivity were used to investigate the structural properties of cholesterol-containing lipid bilayers in the fluid state with increasing amounts of polyunsaturated omega-3 lipids. Either the hybrid 1-stearoyl-2-docosahexaenoyl-sn-glycero-3-phosphocholine or the symmetric 1,2-docosahexaenoyl-sn-glycero-3-phosphocholine were added to the mixture of the naturally abundant 1-palmitoyl-2-oleyl-sn-glycero-3-phosphocholine and cholesterol. Our results indicate that the hybrid and the symmetric omega-3 phospholipids affect the microscopic organization of lipid bilayers differently. Cholesterol does not segregate from polyunsaturated phospholipids and, through interactions with them, is able to suppress the formation of non-lamellar structures induced by the symmetric polyunsaturated lipid. However, this order/disorder balance leads to a bilayer whose structural organization cannot be ascribed to either a liquid ordered or to a canonical liquid disordered phase, in that it displays a very loose packing of the intermediate segments of lipid chains. [ABSTRACT FROM AUTHOR]

In high resolution neutron scattering experimental work the use of significantly longer incoming neutron wavelengths compared to the currently widely used cold neutron range can be of significant advantage. Such advantages are to obtain higher data rates at equal resolution conditions, for example in small angle neutron scattering, and to obtain far better resolution, e.g., in neutron spin echo and time-of-flight spectroscopy or both. [ABSTRACT FROM AUTHOR]

A customized portable SAXS instrument has recently been constructed, installed, and tested at the D22 SANS instrument at ILL. Technical characteristics of this newly established plug-and-play SAXS system have recently been reported (J. Appl. Cryst. 2020, 53, 722). An optimized lead shielding arrangement on the SAXS system and a double energy threshold X-ray detector have been further implemented to substantially suppress the unavoidable high-energy gamma radiation background on the X-ray detector. The performance of the upgraded SAXS instrument has been examined systematically by determining background suppression factors (SFs) at various experimental conditions, including different neutron beam collimation lengths and X-ray sample-to-detector distances (SDDX-ray). Improved signal-to-noise ratio SAXS data enables combined SAXS and SANS measurements for all possible experimental conditions at the D22 instrument. Both SAXS and SANS data from the same sample volume can be fitted simultaneously using a common structural model, allowing unambiguous interpretation of the scattering data. Importantly, advanced in situ/real time investigations are possible, where both the SAXS and the SANS data can reveal time-resolved complementary nanoscale structural information. [ABSTRACT FROM AUTHOR]

The European Spallation Source (ESS), which is under construction in Lund (Sweden), will be the leading and most brilliant neutron source and aims at starting user operation at the end of 2023. Among others, two small angle neutron scattering (SANS) machines will be operated. Due to the high brilliance of the source, it is important to minimize the downtime of the instruments. For this, a collaboration between three German universities and the ESS was initialized to develop and construct a unified sample environment (SE) system. The main focus was set on the use of a robust carrier system for the different SEs, which allows setting up experiments and first prealignment outside the SANS instruments. This article covers the development and construction of a SE for SANS experiments with foams, which allows measuring foams at different drainage states and the control of the rate of foam formation, temperature, and measurement position. The functionality under ESS conditions was tested and neutron test measurement were carried out. [ABSTRACT FROM AUTHOR]

As part of the development of the new European Spallation Source (ESS) in Lund (Sweden), which will provide the most brilliant neutron beams worldwide, it is necessary to provide different sample environments with which the potential of the new source can be exploited as soon as possible from the start of operation. The overarching goal of the project is to reduce the downtimes of the instruments related to changing the sample environment by developing plug and play sample environments for different soft matter samples using the same general carrier platform and also providing full software integration and control by just using unified connectors. In the present article, as a part of this endeavor, the sample environment for in situ SANS and dynamic light scattering measurements is introduced. [ABSTRACT FROM AUTHOR]

Copyright of Acta Sedimentologica Sinica is the property of Acta Sedimentologica Sinica Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We created software to simulate the Larmor precession in a setup for SESANS with adiabatic/radio frequency flippers in magnets designed to measure the time-of-flight on pulsed or stationary neutron sources. The values and spatial configurations of the magnetic fields of the existing prototype magnets we used as input data. For an empty setup, we calculate the polarization of a "divergent ribbon beam" 2 cm high, depending on the neutron wavelength λ. In the "scattering experiment", we show how to convert λ to the "spin-echo length" δ. For λ = 10 Å, flippers at a distance of 140 cm and a radio frequency 1 MHz we find δ ≈ 10 μm. Extension to δ = 20 μm is realistic. [ABSTRACT FROM AUTHOR]

The interchain spacing and screening length modification of deuterated PSS (d-PSS) backbone chains in zwitterion-doped PEDOT:d-PSS were studied as a function of the doping concentration using small angle neutron scattering. Results suggest that the dopant, 3-(N,N-Dimethylmyristylammonio)propanesulfonate (DYMAP), forms worm-like micelle structures in the PEDOT:d-PSS dispersion that grow in size as the doping concentration increases. The interchain spacing between negatively charged d-PSS remains unaffected by DYMAP up to 15 mM doping concentration. However, from 15 to 25 mM doping concentration, the interchain spacing increases due to steric interactions of grown DYMAP worm-like micelles with the d-PSS chains. At 30 mM doping concentration, the interchain distance between negatively charged d-PSS chains is reduced due to the gelation of the PEDOT:d-PSS dispersion caused by the crosslinking between long DYMAP worm-like micelles and d-PSS chains. Meanwhile, the screening length of the neutralized d-PSS segments attached to the PEDOT oligomers increases as the DYMAP concentration increases form 5 to 30 mM due to the neutralization of the negatively charged d-PSS segments by their Coulomb interaction with the cation in DYMAP. [ABSTRACT FROM AUTHOR]

Glucose oxidase (GOx) is a 160 kDa flavoenzyme dimer belonging to the family of glucose-methanol-choline oxidoreductases. Despite the abundant availability of information regarding the structure and mechanisms of interactions of GOx, there is still considerable interest in studying the properties of this protein to extend its bio-applications. The present study aims at investigating the conformational stability of GOx from Aspergillus niger in the optimal environment that presumably preserves its functional properties using small angle neutron scattering method. This method allowed computing the low-resolution three-dimensional models of the protein. Obtained results indicate protein dimerization in buffer solution pH 5.9, with a maximum particle dimension, Dmax, of 110 Å and Rg of 34.50 ± 0.025 Å. [ABSTRACT FROM AUTHOR]

Amphiphilic copolymers with poly (alkyl acrylate) as hydrophobic and poly (acrylic acid) (AA) as hydrophilic block have been synthesised. The alkyl chain was varied from butyl to dodecyl, thereby varying systematically the polarity of the hydrophobic block whose length was between 35 and 70, while the PAA block had ~ 100 units. Such relatively short amphiphiles should equilibrate quickly in aqueous solution, and their corresponding self-assembly properties were characterised by means of critical micelle concentration (cmc) determination. Detailed information regarding the aggregate structures was obtained by static light scattering (SLS) and small angle neutron scattering (SANS). This could be correlated with the molecular architecture of the copolymers and the degree of ionisation of the PAA block. Generally, it is found that the aggregation numbers become smaller upon fully charging the PAA head group and only for dodecyl acrylate really well-defined micellar aggregates are formed. This means that the extent of hydrophobicity of the alkyl acrylate block and its length determine in a clear fashion the propensity for micelle formation and the mass and aggregation number of the formed micelles. [ABSTRACT FROM AUTHOR]

Designing artificial protocells to sequester the biomolecules within its compartments is a challenging task and can be achieved through the use of surfactant‐based coacervates. Surfactant structures could be tailored to achieve the highest sequestration through coacervate droplets, irrespective of the polarity, charge and type of the analytes. Herein, we designed a morpholinium‐based ester‐functionalized ionic‐liquid‐based surfactant (ILBS) with a higher surface activity than its analogous conventional surfactant to form complex catanionic coacervates over the broad range of sodium salicylate (NaSal) concentrations. The spherically shaped micellar aggregates of the investigated ILBS are transformed into cylindrical shapes and again in the spherically shaped micellar aggregates depending on the NaSal concentration, which forms the coacervate droplets. The complex catanionic coacervates have been studied for their stability in the presence of mono and divalent cations, pH, temperature, viscosity and with respect to time. The microfluidic channel of 100 μm internal diameter was designed to obtain coacervate droplets with a maximum size of 100 μm. The coacervates were designed based on the NaSal concentration; cationic, neutral and anionic to exhibit selective and non‐selective encapsulation of the model charged dyes. We speculate that the strategically designed coacervate droplets could mimic membrane‐free protocells, which are applicable in multiple biomimetic operations. [ABSTRACT FROM AUTHOR]

While spherical particles are the most studied viscosity modifiers, they are well known only to increase viscosities, in particular at low concentrations of approx. 1%. Extended studies and theories on non-spherical particles in simple fluids find a more complicated behavior, but still a steady increase with increasing concentration. Involving platelets in combination with complex fluids—in our case, a bicontinuous microemulsion—displays an even more complex scenario that we analyze experimentally and theoretically as a function of platelet diameter using small angle neutron scattering, rheology, and the theory of the lubrication effect, to find the underlying concepts. The clay particles effectively form membranes in the medium that itself may have lamellar aligned domains and surfactant films in the case of the microemulsion. The two-stage structure of clay and surfactant membranes explains the findings using the theory of the lubrication effect. This confirms that layered domain structures serve for lowest viscosities. Starting from these findings and transferring the condition for low viscosities to other complex fluids, namely crude oils, even lowered viscosities with respect to the pure crude oil were observed. This strengthens our belief that also here layered domains are formed as well. This apparent contradiction of a viscosity reduction by solid particles could lead to a wider range of applications where low viscosities are desired. The same concepts of two-stage layered structures also explain the observed conditions for extremely enhanced viscosities at particle concentrations of 1% that may be interesting for the food industry. [ABSTRACT FROM AUTHOR]

To overcome the limitation of polymeric and ceramic membranes in terms of performance and durability for water treatment, mixed-matrix membranes are being increasingly studied. In our studies, mixed matrix membranes of functionalized multiwalled carbon nanotubes (MWCNTs) with polyether sulfone as the membrane matrix showed reduced porosity. The pore dimensions, when studied by small angle neutron scattering and capillary flow porometry techniques, showed smaller pores. The cross sectional image of cold fractured membrane obtained from scanning electron microscopy showed that they retained their original asymmetric nature when cast by the phase inversion technique. The thermogravimetric analysis of mixed-matrix membranes showed enhanced thermal properties and better stability to degradation than the pristine membranes with no loss in the stability. These membranes showed better separation characteristics and enhanced selectivity for metal ion separation. Interestingly, the conductivity in dry state of the mixed-matrix membranes showed perfectly semicircular plots which shows conducting nature of the membranes which is attributed to the presence of functionalized nanotubes in the otherwise insulating polymer matrix. [ABSTRACT FROM AUTHOR]

Third phase (TP) formation in the extraction of Th(IV) by tris(2-methylbutyl) phosphate (T2MBP) from HNO3 media was studied and compared with tri-n-butyl phosphate (TBP) systems. Concentrations of Th(IV) and HNO3 and densities of organic phases were determined as a function of Th(NO3)4 concentration. Extractant concentrations and volume ratios in the triphasic regions were also measured. The extraction experiments show lower TP formation tendency of T2MBP. The aggregation behaviour of Th(IV) loaded solutions of tri-n-amyl phosphate (TAP), T2MBP and TBP in n-C8D18 and n-C12D26 were investigated using small angle neutron scattering technique and found to be in correlation with TP formation trends. [ABSTRACT FROM AUTHOR]

The aim of this study is to explore in-depth microstructural changes induced by Plasma Electrolytic Saturation nitriding and carburizing treatments applied to the AISI 304L steel. The obtained structures were characterized by X-Ray Diffraction, Metallography, X-ray Photoelectron Spectroscopy and Small Angle Neutron Scattering; an assessment of the results is presented. [ABSTRACT FROM AUTHOR]

Here we combine small angle neutron scattering measurements (SANS) with X-ray diffraction analysis (XRD) and infrared spectroscopy (IR) measurements to obtain information about nanoparticles formed in a series of lead-lead dioxide samples mixed with various CuO concentrations. New vitreous systems with the xCuO • (100−x)[4PbO2 • Pb] composition where x = 0, 30, and 70 mol% CuO were prepared by the melt-quenching method using CuO mixed in suitable proportion with the active electrodes of a disassembled car battery as the starting materials. The X-ray diffraction patterns permit the identification of the metallic Pb phase and the presence of oxidic nanoparticles of the lead and copper ions. By doping with higher CuO contents, the SANS curves have a concave shape indicating inhomogeneities and tendency of phase separation due to formation of nanoparticles of the lead and copper ions in recycled host matrix. The studied samples can be considered as polydispersed systems. The matrix is the solvent and the soluble phase is formed from the oxidic lead and/or copper particles with sizes smaller than 69 Å dispersed either inside the host matrix grains or between the host matrix grains. The formation of the nanoparticles in the host matrix and the knowledge of the type of nanoparticles have a decisive role in applications for the construction of essential components of the automobile batteries. [ABSTRACT FROM AUTHOR]

Abstract: Two amphiphilic random copolymers, PEGMAx‐co‐FAy (x = 90 and 70 mol%), are synthesized by ATRP and their solutions are investigated as a function of solvent, concentration, and temperature by DLS and SANS analyses. Both copolymers self‐assemble in nanostructures by single‐chain folding in water solutions over a wide range of temperatures. The values of the DLS hydrodynamic radius and the SANS radius of gyration are found to be ≈4 nm and ≈3.4–3.7 nm, respectively. Moreover, SANS shows the self‐folded nanoassemblies to be prolated spheroids with a ratio of polar/equatorial axes of ≈5:1 for PEGMA90‐co‐FA10 and ≈2:1 for PEGMA70‐co‐FA30. On heating above a critical temperature Tc, multichain microassemblies are formed that revert back to nanoassemblies on cooling below Tc. This temperature‐responsive transition is fully and sharply reversible. [ABSTRACT FROM AUTHOR]

We have succeeded in synthesizing orthorhombic Ga(1_X)Fe(1+X)03 (-0.05 ≤ x ≤ 0.5), hexagonal GayFe(2-y)O3 (0 ≤ y ≤1.8) and cubic Ga(1+Z)Fe(2-Z)04 (--0.1 ≤ z ≤ 0.8) nanograins of gallium ferrites using conventional precursors and an organic environment of Pechini scenario under atmosphericpressure conditions (SG method). Phase composition and homogeneity were analyzed using X-ray diffraction. Small angle neutron scattering disclosed ellipsoidal particle shapes of gallium iron oxides (GFO) crystallizing in orthorhombic (o-GFO) and hexagonal (h-GFO) symmetry and parallelepiped shapes of Ga(1+y)Fe(2-y)O4 (c-GFO) grains. Despite local agglomeration among the magnetic grains, the scanning electron microscopy and transmission electron microscopy images point to faced-elliptical shapes. The Mössbauer spectroscopy with magnetization measurements was carried out in the temperature range of 5-295 K. The analysis of gallium ferrites magnetism demonstrates that iron atoms locate with various probabilities in crystallography positions and the spontaneous magnetization preserves up to room temperature (RT). [ABSTRACT FROM AUTHOR]

The 2nd biennial International Society for Sample Environment (ISSE) School included training on high pressure (HP) cells for Soft Matter studies. Neutron research centers are responding to a growing need for HP experimental data, relevant to a broad range of applications in bioscience, biotechnology and others. The importance of disseminating designs and operating protocols, to support concerted efforts towards the advancement of sample environment instrumentation across research centers, was repeatedly acknowledged at the ISSE school. The liquid insertion HP system for SANS, currently used at the NIST Center for Neutron Research for solutions of biological macromolecules, is described here. Emphasis is placed on the context of subzero temperature studies and the design challenges. The current model of the HP system – HP up to 3.5 kbar and −18°C < T < +80°C – uses sample volumes of 2.7 ml to cover an accessible q-range of 0.001–0.6 Å−1. [ABSTRACT FROM AUTHOR]

We have developed and realised a compact high-pressure clamp cell of the piston-cylinder type for Small Angle Neutron Scattering (SANS) and Neutron Spin Echo (NSE) spectroscopy measurements. The cell can pressurise ⌀5 mm samples up to 1.5 GPa. It is non-magnetic, produces a sufficiently low and flat SANS background with a relatively good neutron transmission and can be used in combination with polarised neutrons. The cell accommodates samples of up to 55 mm3 in volume and adopts a two-layer geometry: a TiZr body (outer layer) and a CuBe2 insert (inner layer). Its design is very compact and can be employed inside cryomagnets featuring a sample bore greater than ⌀30 mm. We present the cell and illustrate its performances with a series of neutron scattering experiments performed on single-crystalline MnSi. [ABSTRACT FROM AUTHOR]

Maraging steels gain many of their beneficial properties from heat treatments which induce the precipitation of intermetallic compounds. We consider here a two-stage heat-treatment, first involving austenitisation, followed by quenching to produce martensite and then an ageing treatment at a lower temperature to precipitation harden the martensite of a maraging steel. It is shown that with a suitable choice of the initial austenitisation temperature, the steel can be heat treated to produce enhanced toughness, strength and creep resistance. A combination of small angle neutron scattering, scanning electron microscopy, electron back-scattered diffraction and atom probe tomography were used to relate the microstructural changes to mechanical properties. It is shown that such a combination of characterisation methods is necessary to quantify this complex alloy and relate these microstructural changes to mechanical properties. It is concluded that a higher austenitisation temperature leads to a greater volume fraction of smaller Laves phase precipitates formed during ageing, which increase the strength and creep resistance but reduces toughness. [ABSTRACT FROM AUTHOR]

Wood decayed by brown rot fungi and wood treated with the chelator-mediated Fenton (CMF) reaction, either alone or together with a cellulose enzyme cocktail, was analyzed by small angle neutron scattering (SANS), sum frequency generation (SFG) spectroscopy, Fourier transform infrared (FTIR) analysis, X-ray diffraction (XRD), atomic force microscopy (AFM), and transmission electron microscopy (TEM). Results showed that the CMF mechanism mimicked brown rot fungal attack for both holocellulose and lignin components of the wood. Crystalline cellulose and lignin were both depolymerized by the CMF reaction. Porosity of the softwood cell wall did not increase during CMF treatment, enzymes secreted by the fungi did not penetrate the decayed wood. The enzymes in the cellulose cocktail also did not appear to alter the effects of the CMF-treated wood relative to enhancing cell wall deconstruction. This suggests a rethinking of current brown rot decay models and supports a model where monomeric sugars and oligosaccharides diffuse from the softwood cell walls during non-enzymatic action. In this regard, the CMF mechanism should not be thought of as a “pretreatment” used to permit enzymatic penetration into softwood cell walls, but instead it enhances polysaccharide components diffusing to fungal enzymes located in wood cell lumen environments during decay. SANS and other data are consistent with a model for repolymerization and aggregation of at least some portion of the lignin within the cell wall, and this is supported by AFM and TEM data. The data suggest that new approaches for conversion of wood substrates to platform chemicals in biorefineries could be achieved using the CMF mechanism with >75% solubilization of lignocellulose, but that a more selective suite of enzymes and other downstream treatments may be required to work when using CMF deconstruction technology. Strategies to enhance polysaccharide release from lignocellulose substrates for enhanced enzymatic action and fermentation of the released fraction would also aid in the efficient recovery of the more uniform modified lignin fraction that the CMF reaction generates to enhance biorefinery profitability. [ABSTRACT FROM AUTHOR]

Macroporous polymeric membranes involved in the large scale purification of biopharmaceuticals (vaccines, monoclonal antibodies, therapeutic enzymes etc.) are manufactured by inducing liquid-liquid demixing in a polymer solution. In this regard, evaporative casting is known to be one of the most important industrial techniques for the large scale production of such polymeric membranes. Next generation vaccines will require membranes with higher integrity and sharper pore size distributions. Time-resolved Small Angle Neutron Scattering (SANS) is a powerful tool for the resolution of demixing processes at microscopic scale and a great approach for boosting the progress to be achieved by membrane scientists in understanding and controlling the mechanisms of membrane formation. The present contribution reports on the development of an experimental set-up using a dedicated Neutron-Transparent Flow-Through Cell (further referred as NTFT-Cell) for the characterization of liquid-liquid-demixing during industrial evaporative casting. After a detailed description of the set-up and its implementation within D11 instrument (Institut Laue-Langevin, ILL, Grenoble, France), first results from exemplary investigations in the quaternary system cellulose nitrate/methyl acetate/ispopropanol/deuterium oxide were presented. [ABSTRACT FROM AUTHOR]

Protein small angle scattering (SAS) has become increasing important in structural biochemistry, due to the increased performance and specification of new instruments and advances in the software and hardware used to analyse the data. Whilst all of this is encouraging, there is a lack of standardised experimental methodology within the community. Although a number of protein standards are currently used in SAS experiments to allow accurate molecular weight determination, each has specific advantages and disadvantages. We therefore propose the use of a mutated monomeric enhanced green fluorescent protein, as a protein standard, abbreviated to m-eGFP. It has a number of advantages over the currently used protein standards, for example it is cheap and easy to produce. It can be expressed in large amounts (>40 mg/L) in both hydrogenated and deuterated form. The mutation means it is highly monodisperse and GFP being a beta-barrel structure is thermodynamically stable over a number of days, giving highly reproducible results. We therefore believe m-eGFP is a good protein standard for small angle scattering (SAS). [ABSTRACT FROM AUTHOR]

The most abundant cartilage proteoglycan is aggrecan, a bottlebrush shaped molecule that possesses over 100 glycosaminoglycan (chondroitin sulfate and keratan sulfate) chains. The side-chains are linear sulfated polysaccharides that are negatively charged under physiological conditions. Aggrecan interacts with hyaluronic acid (HA) to form large aggregates. Osmotic pressure measurements and rheological measurements are used to study the static and dynamic behavior of aggrecan assemblies at the macroscopic length scales. The microscopic properties of aggrecan solutions are determined by small angle neutron scattering, and static and dynamic light scattering (SLS and DLS). In dilute solutions aggrecan forms microgels with a diffuse boundary, composed of loosely connected clusters. The osmotic pressure of the aggrecan-HA system decreases with increasing HA content. DLS yields a relaxation rate that varies as q3, arising from internal modes in the microgel. The relaxation rate in the solutions of the aggrecan-HA complex is slightly greater than in the pure aggrecan solution. [ABSTRACT FROM AUTHOR]

The main objective of this work was to study the electric response of the carbon nanotubes/epoxy composites upon varying the concentrations of the nanotubes, in order to obtain a comprehensive understanding of the influence of filler’s percentage and temperature on the impedance parameters. Dielectric spectra of the carbon nanotubes–epoxy resin composites were recorded in the frequency range of 1 Hz–10 MHz and over the temperature range of 25°C–105°C. In a first part, the thermal properties of the composites were analyzed by differential scanning calorimetry, which reveals a decrease in the glass transition temperatures with the concentration of the nanotubes. The phenomenon of the positive temperature coefficient in resistivity that is recognizable for the carbon nanotube concentrations above the percolation threshold has been the interest of the second part of the work. The results reveal that gradually, as the filler concentration approaches the percolation threshold of the composite, the positive temperature coefficient in the resistivity effect becomes even more pronounced. Finally, the structure of the filled polymer samples is characterized using a small angle neutron scattering technique. [ABSTRACT FROM PUBLISHER]

ABSTRACT The purpose of this study is to identify the relationship between the electrical and structural characteristics of multiwalled carbon nanotubes dispersed into the polymer matrix of a resin. In a first step, the composites were characterized by small-angle neutron scattering, which provide information about the bulk dispersion of nanotubes in the matrix and form three-dimensional networks with a surface fractal behavior. In the second step, a dielectric and electrical study was carried out in the frequency range between 1 Hz and 10 MHz at room temperature. We have found that the electric and dielectric behavior of these composites can be described by Jonscher's universal dielectric response. We show that the critical exponents describing the concentration dependence of the conductivity and the dielectric constant, obtained in the vicinity of the percolation threshold, are in good agreement with the theoretical values. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44514. [ABSTRACT FROM AUTHOR]

Background: Human lactoferrin is an iron-binding protein of the innate immune system consisting of two connected lobes, each with a binding site located in a cleft. The clefts in each lobe undergo a hinge movement from open to close when Fe3+ is present in the solution and can be bound. The binding mechanism was assumed to relate on thermal domain fluctuations of the cleft domains prior to binding. We used Small Angle Neutron Scattering and Neutron Spin Echo Spectroscopy to determine the lactoferrin structure and domain dynamics in solution. Results: When Fe3+ is present in solution interparticle interactions change from repulsive to attractive in conjunction with emerging metas aggregates, which are not observed without Fe3+. The protein form factor shows the expected change due to lobe closing if Fe3+ is present. The dominating motions of internal domain dynamics with relaxation times in the 30-50 ns range show strong bending and stretching modes with a steric suppressed torsion, but are almost independent of the cleft conformation. Thermally driven cleft closing motions of relevant amplitude are not observed if the cleft is open. Conclusion: The Fe3+ binding mechanism is not related to thermal equilibrium fluctuations closing the cleft. A likely explanation may be that upon entering the cleft the iron ion first binds weakly which destabilizes and softens the hinge region and enables large fluctuations that then close the cleft resulting in the final formation of the stable iron binding site and, at the same time, stable closed conformation. [ABSTRACT FROM AUTHOR]

Distribution ratios for the extraction of Zr(IV) and Hf(IV) as well as third phase formation limits for the extraction of Zr(IV) by solutions of tri- iso-amyl phosphate (T iAP) and tri- n-butyl phosphate (TBP) in n-dodecane have been measured as a function of equilibrium aqueous phase nitric acid concentration at 303 K. The concentrations of the constituents of the organic phases at different equilibrium aqueous phase Zr(IV) concentrations were determined and correlated with the third phase formation tendency of T iAP and TBP. The aggregation behaviour of T iAP and TBP in the extraction of Zr(IV) from its solution in nitric acid media (4.06-4.41 M HNO) has been compared using small angle neutron scattering technique. Studies indicate the higher third phase formation tendency of TBP as compared to T iAP in the extraction of Zr(IV) from nitric acid media. [ABSTRACT FROM AUTHOR]

Scattering functions of sodium sulfonated polystyrene (NaPSS) star-branched polyelectrolytes with high sulfonation degrees were measured from their salt-free aqueous solutions, using the Small Angle Neutron Scattering (SANS) technique. Whatever the concentration c, they display two maxima. The first, of abscissa q1*, is related to a position order between star cores and scales as q1* ∝ c1/3. The second, of abscissa q2*, is also observed in the scattering function of a semi-dilute solution of NaPSS linear polyelectrolytes. In the dilute regime (c < c*, non-overlapping stars), peak abscissa does not depend on concentration c and is just an intramolecular characteristic associated with the electrostatic repulsion between arms of the same star. In the semi-dilute regime, due to the star interpenetration, the scattering function - through the peak position, reflects repulsion between arms of the same star or of different stars. The c threshold between these distinct c-dependencies of q2* in the dilute and semi-dilute regimes is estimated as c*. Just as simple is the measurement of the geometrical radius R of the star obtained from the q1* value at c* through the relation 2R = 2π/q1*. By considering NaPSS stars of the same functionality with different degrees of polymerization per arm Na, we find R scaling linearly with Na, suggesting an elongated average conformation of the arms. This is in agreement with theoretical predictions and simulations. Meanwhile the value of q2* measured in the dilute regime does not allow any inhomogeneous counterion distribution inside the stars to be revealed. [ABSTRACT FROM AUTHOR]

A better understanding of how wood nanostructure swells with moisture is needed to accelerate the development of forest products with enhanced moisture durability. Despite its suitability to study nanostructures, small angle neutron scattering (SANS) remains an underutilized tool in forest products research. Nanoscale moisture-induced structural changes in intact and partially cut wood cell walls were investigated using SANS and a custom-built relative humidity (RH) chamber. SANS from intact wood sections cut from each primary wood orientation showed that although wood scattered anisotropically across 1.3-600 nm length scales, measurement of elementary fibril spacing and low- q surface scattering were independent of orientation. Water sorption caused spacing between elementary fibrils to increase with RH, and this swelling accounted for over half the transverse swelling in S2 secondary wood cell walls. Elementary fibril spacing in longitudinally cut wood cells, which were designed to mimic cells near wood-adhesive bondlines, was greater than the spacing in intact cells above 90 % RH. This suggested that some cell wall hoop constraint from the S1 and S3 cell wall layers on the S2 layer was released by cutting the cells. Furthermore, increased spacing between elementary fibrils may also create diffusion channels that are hypothesized to be responsible for the onset of fungal decay in wood. Protocols were established to use SANS in future research to study adhesives and protection treatments to improve moisture durability in forest products. [ABSTRACT FROM AUTHOR]

Bainite transformation behavior was monitored using simultaneous measurements of dilatometry and small angle neutron scattering (SANS). The volume fraction of bainitic ferrite was estimated from the SANS intensity, showing good agreement with the results of the dilatometry measurements. We propose a more advanced monitoring technique combining dilatometry, SANS and neutron diffraction. [ABSTRACT FROM AUTHOR]