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[Display omitted] Nonionic surfactant aerosols play a crucial role in many industries, but they can cause acute irritation to users' eyes during spraying. This cytotoxic process is associated with corneal cell necrosis causing cell membrane disruption. Industrial grade surfactants are typically polydisperse mixtures described by their nominal chemical structure but how the polydispersity affects their interactions with cell membrane, remains largely unexplored. A better understanding could benefit product formulations to maximise their efficiency whilst minimising their toxicity to the users. In this study, poly - oxyethylene glycol monododecyl ethers (C 12 E 4 , C 12 E 23) were used to form ideal binary surfactant mixtures. The cytotoxicities of mono and polydispersed surfactants towards human corneal epithelial cells were examined, followed by a series of biophysical characterisations of interactions between surfactants and model cell membranes. Notably, to probe the journey of individual C 12 E 4 and C 12 E 23 surfactant molecules across the cell membrane from a binary surfactant mixture, "two-colour" neutron reflection measurements were achieved via Hydrogen/Deuterium substitution. The relative distributions of C 12 E 4 and C 12 E 23 across cell membranes and their nanostructural conformations revealed a synergistic membrane-lytic ability initiated by surfactant mixing, with the more hydrophobic C 12 E 4 exhibiting stronger membrane binding potency than the hydrophilic C 12 E 23. The exact molar ratio of C 12 E 4 against C 12 E 23 in the mixture determined how the mixed surfactant interacted with the cell membrane, and how the process directly impacted cytotoxicity and eye irritation. Thus, the cytotoxicity of polydisperse surfactants is not the same as monodisperse surfactant of the same average structure. This work provides a useful basis for the assessment of surfactant mixing by balancing their efficiency and toxicity. [ABSTRACT FROM AUTHOR]

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 formation of distorted lamellar phases, distinguished by their arrangement of crumpled, stacked layers, is frequently accompanied by the disruption of long-range order, leading to the formation of interconnected network structures commonly observed in the sponge phase. Nevertheless, traditional scattering functions grounded in deterministic modeling fall short of fully representing these intricate structural characteristics. Our hypothesis posits that a deep learning method, in conjunction with the generalized leveled wave approach used for describing structural features of distorted lamellar phases, can quantitatively unveil the inherent spatial correlations within these phases. This report outlines a novel strategy that integrates convolutional neural networks and variational autoencoders, supported by stochastically generated density fluctuations, into a regression analysis framework for extracting structural features of distorted lamellar phases from small angle neutron scattering data. To evaluate the efficacy of our proposed approach, we conducted computational accuracy assessments and applied it to the analysis of experimentally measured small angle neutron scattering spectra of AOT surfactant solutions, a frequently studied lamellar system. The findings unambiguously demonstrate that deep learning provides a dependable and quantitative approach for investigating the morphology of wide variations of distorted lamellar phases. It is adaptable for deciphering structures from the lamellar to sponge phase including intermediate structures exhibiting fused topological features. This research highlights the effectiveness of deep learning methods in tackling complex issues in the field of soft matter structural analysis and beyond. [ABSTRACT FROM AUTHOR]

[Display omitted] Aqueous suspensions of cellulose nanocrystals (CNC) form a re-entrant liquid crystal (LC) phase with increasing salinity. Phase separation occurs in this LC state leading to a biphasic gel with a flow programmable structure that can be used to form anisotropic soft materials. We term this state a Liquid Crystal Hydroglass (LCH). Defining the mechanisms by which the LCH forms requires detailed structural analysis at the mesoscopic length scale. By utilising Small Angle Neutron Scattering (SANS), we investigated the microstructure transitions in CNC suspensions, with a particular focus on the unique LC re-entrancy and gelation into the biphasic LCH. Scattering from LCH gels comprises contributions from a dispersed liquid state and static heterogeneity, characterised using a Lorentzian-Gaussian model of inhomogeneity. This conceptually supports a gelation mechanism (spinodal decomposition) in CNC suspensions towards a biphasic structure of the LCH. It also demonstrates that, with increasing salinity, the non-monotonic variation in effective volume fraction of CNC rods fundamentally causes the LC re-entrancy. This work provides the first experimental characterisation of the LC-re-entrancy and formation of an anisotropic LCH gel. The proposed mechanism can be extended to understanding the general behaviour of anisotropic colloids. [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]

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]

[Display omitted] The superchaotropic Keggin polyoxometalate α-SiW 12 O 40 4− (SiW) was recently shown to stabilize non-ionic surfactant (C 18:1 E 10) foams owing to electrostatic repulsion that arises from the adsorption of SiW-ions to the foam interfaces. The precise mechanism of foam stabilization by SiW however remained unsolved. Imaging and conductimetry were used on macroscopic foams to monitor the foam collapse under free drainage and small angle neutron scattering (SANS) at a given foam height allowed for the tracking of the evolution of film thickness under quasi-stationary conditions. Thin film pressure balance (TFPB) measurements enabled to quantify the resistance of single foam films to external pressure and to identify intra-film forces. At low SiW/surfactant ratios, the adsorption of SiW induces electrostatic repulsion within foam films. Above a concentration threshold corresponding to an adsorption saturation, excess of SiW screens the electrostatic repulsion that leads to thinner foam films. Despite screened electrostatics, the foam and single foam films remain very stable caused by an additional steric stabilizing force consistent with the presence of trapped micelles inside the foam films that bridge between the interfaces. These trapped micelles can serve as a surfactant reservoir, which promotes self-healing of the interface leading to much more resilient foam films in comparison to bare surfactant foams/films. [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]

The structure–property studies in unpolymerized and polymerized tannic acid incorporated hydrogels exhibited the presence of micron sized aggregates. The hydrogen bonded aggregates breaks at high temperatures for the unpolymerized and polymerized cases as evident from the scattering studies. The structural changes is clearly reflected in rheological properties for the unpolymerized case as a clear elastic to dissipative transition while the polymerized case exhibited dissipation even at higher temperatures. [Display omitted] Hydrogels made with semi-interpenetrating networks of the oligomerized polyphenol tannic acid, and poly(acrylamide), exhibit high stiffness and toughness. However, the structure property relationships that give rise to enhanced mechanical properties is not well understood. Herein, we systematically investigate the hydrogels using small angle X-ray scattering and small and Ultra-small angle neutron scattering within a wide length scale range (1 nm to 20 µm), polarized optical microscopy, and rheology. Small angle X-ray and neutron scattering reveal the presence of micron sized hydrogen bonded clusters in the hydrogels. Breaking of hydrogen bonded clusters above a critical solution temperature was clearly observed in the small angle neutron scattering data. Polarized optical microscopy show enhanced anisotropy for the gels with oligomerized tannic acid incorporated - when compared to gels with monomeric tannic acid. Rheological studies at varying temperatures nicely corroborate the structural changes observed at high temperatures and reveal a self-healing behavior of the gels. The knowledge gained from this study will aid in rational design of hydrogels for biomedical applications. [ABSTRACT FROM AUTHOR]

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]

[Display omitted] Mixtures of hyaluronic acid (HA) with liposomes lead to hybrid colloid–polymer systems with a great interest in drug delivery. However, little is known about their microstructure. Small angle neutron scattering (SANS) is a valuable tool to characterize these systems in the semi-dilute entangled regime (1.5% HA) at high liposome concentration (80 mM lipids). The objective was to elucidate the influence of liposome surface (neutral, cationic, anionic or anionic PEGylated), drug encapsulation and HA concentration in a buffer mimicking biological fluids (37 °C). First, liposomes were characterized by SANS, cryo-electron microscopy, and dynamic light scattering and HA by SANS, size exclusion chromatography, and rheology. Secondly, HA-liposome mixtures were studied by SANS. In HA, liposomes kept their integrity. Anionic and PEGylated liposomes were in close contact within dense clusters with an amorphous organization. The center-to-center distance between liposomes corresponded to twice their diameter. A depletion mechanism could explain these findings. Encapsulation of a corticoid did not modify this organization. Cationic liposomes formed less dense aggregates and were better dispersed due to their complexation with HA. Liposome surface governed the interactions and microstructure of these hybrid systems. [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]

[Display omitted] Hypothesis: Saponins are a class of plant derived surfactants which are widely used in food related foams and emulsions, aerated drinks, and in pharmaceuticals and cosmetics. As a potential biosourced and renewable ingredient in a wider range of surfactant based formulations their potential is intimately associated with their mixing with synthetic surfactants. As such the nature of the mixed saponin-surfactant self-assembly is an important characteristic to investigate and understand. The unconventional structure of the saponins compared to the conventional synthetic surfactants poses some interesting constraints on the structures of the mixed aggregates. Experiments: Small angle neutron scattering, SANS, is used to investigate the structure of the saponin, escin, mixed with a range of nonionic surfactants with different ethylene oxide groups, from triethylene glycol monododecyl ether, C 12 E 3 , to dodecaethylene glycol monododecyl ether, C 12 E 12. Findings: The scattering data reveal a complex evolution in the solution self-assembled structure with varying escin / nonionic composition and ethylene oxide chain length. The rich structural development comprises of the evolution from the elongated micelle structure of escin to the micelle structure of the nonionic surfactant. At the intermediate solution compositions the structure is predominantly planar, comprising mostly of planar / micellar mixed phases. The nature of the planar structures depend upon the ethylene oxide chain length and the solution composition, and include lamellar, bilamellar vesicle, multilamellar vesicle, and nanovesicle structures, in common with what is observed in other surfactant mixtures. [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]

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 this article we present the first experimental evidence confirming a global presence of Buckminsterfullerene (C 60) in non-graphitizing polymeric carbon, along with its volume fraction calculations. Partially stacked carbon fragments featuring weak or strong curvatures constitute the structural units in non-graphitizing carbons. It has been proposed that a certain fraction of completely closed spherical fullerenes, such as C 60 , is also present in these materials. Strongly curved structures are not expected to exist in graphitizing carbons. We report on a Small Angle Neutron Scattering (SANS) investigation conducted at the Institut Laue-Langevin, Grenoble, France, that enables us to (i) quantify C 60 in a non-graphitizing carbon, (ii) investigate the evolution patterns of graphitizing and non-graphitizing carbons, and (iii) perform a detailed SANS analysis of pure crystalline C 60 in dry powder form. We also revisit the formation patterns of slightly larger structures (3–5 nm) such as graphitic crystallites and voids in both classes of polymeric carbon. These results provide a strong evidence in support of the fullerene-like microstructural models of non-graphitizing carbon, adding that the curved structural units are not just "fullerene-like", but also spherical fullerenes, C 60 in particular. [Display omitted] • Non-graphitizing carbons contain spherical fullerenes in addition to curved fragments. • Volume fraction of C 60 in carbon derived from a phenol-formaldehyde resin is ∼7%. • Graphitizing carbons do not contain spherical and closed fullerenes. [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]

[Display omitted] There is an increased interest in the use of natural surfactant as replacements for synthetic surfactants due to their biosustainable and biocompatible properties. A category of natural surfactants which are attracting much current interest is the triterpenoid saponins; surface active components found extensively in a wide range of plant species. A wide range of different saponin structures exist, depending upon the plant species they are extracted from; but regardless of the variation in structural details they are all highly surface active glycosides. Greater exploitation and application requires a characterisation and understanding of their basic adsorption and self-assembly properties. Glycyrrhizic acid, extracted from Licorice root, is a monodesmosidic triterpenoid saponin. It is widely used in cosmetic and pharmaceutical applications due to its anti-inflammatory properties, and is an ingredient in foods as a sweetener additive. It has an additional attraction due to its gel forming properties at relatively low concentrations. Although it has attracted much recent attention, many of its basic surface active characteristics, adsorption and self-assembly, remain relatively unexplored. How the structure of the Glycyrrhizic acid saponin affects its surface active properties and the impact of gelation on these properties are important considerations, and to investigate these are the focus of the study. In this paper the adsorption properties at the air–water interface and the self-assembly in solution have been investigated using by neutron reflectivity and small angle neutron scattering; in non-gelling and gelling conditions. The adsorption isotherm is determined in water and in the presence of gelling additives, and compared with the adsorption behaviour of other saponins. Gelation has minimal impact on the adsorption; apart from producing a rougher surface with a surface texture on a macroscopic length scale. Globular micelles are formed in aqueous solution with modest anisotropy, and are compared with the structure of other saponin micelles. The addition of gelling agents results in only minimal micelle growth, and the solutions remain isotropic under applied shear flow. [ABSTRACT FROM AUTHOR]

[Display omitted] Liquid lipid nanoparticles (LLN) are oil-in-water nanoemulsions of great interest in the delivery of hydrophobic drug molecules. They consist of a surfactant shell and a liquid lipid core. The small size of LLNs makes them difficult to study, yet a detailed understanding of their internal structure is vital in developing stable drug delivery vehicles (DDVs). Here, we implement machine learning techniques alongside small angle neutron scattering experiments and molecular dynamics simulations to provide critical insight into the conformations and distributions of the lipid and surfactant throughout the LLN. We simulate the assembly of a single LLN composed of the lipid, triolein (GTO), and the surfactant, Brij O10. Our work shows that the addition of surfactant is pivotal in the formation of a disordered lipid core; the even coverage of Brij O10 across the LLN shields the GTO from water and so the lipids adopt conformations that reduce crystallisation. We demonstrate the superior ability of unsupervised artificial neural networks in characterising the internal structure of DDVs, when compared to more conventional geometric methods. We have identified, clustered, classified and averaged the dominant conformations of lipid and surfactant molecules within the LLN, providing a multi-scale picture of the internal structure of LLNs. [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]

The surface is reacting to form layers of oxide, which lead to complex early hydriding processes prior to mass hydrogen reaction. The existence of oxide layers on top of the metal makes observation of early hydride initiation a challenging task. However, understanding of the initial hydrogen reaction mechanism of "real-life" metals is crucial for predicting the overall corrosion behaviour and properties of the material over time. To observe hydriding initiation in-situ, the small angle neutron scattering (SANS) was utilized through enhancing the signals coming from the surface structure by a special hydrogen reaction chamber. The analysis of early uranium hydriding was presented and proved traceable for deuteride precipitation. In addition, the initial deuterides were measure in-situ and in a non-destructive fashion for the first time. The deuterides were found to form when D 2 consumption was accelerated (≤0.4 μmol/cm2) in uranium. The present study allowed us to analyze the initial hydrides nucleation and relate it to hydrogen consumption, thus facilitating the study on the initial hydrogen reaction mechanism. • Present an in-situ method to demonstrate the dynamics of hydride phase formation. • Exactly identify the induction period of the hydrogen-metal reactions. • An alternative method investigating the incipient stages of hydriding reaction. [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]

The work presents the characterization of Pluronic F127 micellar solutions in presence of hyaluronic acid in semi-dilute regime. The effects of the nature and salt concentration are investigated by differential scanning calorimetry and small angle neutron scattering. Hyaluronic acid reduces the critical micellar temperature to the same extend as an increase of the ionic strength. Within the investigated HA concentration range, the size and shape of the micelles are not modified by the addition of HA but their dispersion state depends on the salt concentration. By increasing the ionic strength we observe the formation of small micellar clusters which organize into a face-centered cubic liquid crystalline phase at high salt concentration. This behavior is reinforced by increasing the HA concentration or molecular weight. The nature of the salt plays also a role and divalent cations such as Ca2+ promote the clustering of micelles and their crystallization. The origin of the aggregative behavior is the change of the HA chain conformation –from stretched to coil- by addition of salt which in turn induces an excluded volume around the micelles and exerts a depletion interaction. [ABSTRACT FROM AUTHOR]

The kinetics of the dynamic instantaneous dissolution of the precipitated phases in 2195-T6 Al-Li alloy under high strain rate loading was firstly studied quantitatively by means of the small angle neutron scattering (SANS) and transmission electron microscopy (TEM) techniques, and the thermodynamics and transformation mechanism were also illustrated in this paper. The high strain rate loadings were performed by the split Hopkinson pressure bar. The maximum flow stresses increased but the pulse durations decreased with increasing strain rates. TEM observations indicated that the size and volume fraction of the T 1 phases decreased. The SANS fitting results showed that the radius and volume fraction of the T 1 phase decreased after loading. The dissolution activation energy (Q d) was calculated to be 28.4 kJ/mol by combining the Johnsone-Mehl-Avrami-Kolmogorov (JMAK) equation and the Arrhenius equation, indicating that the instantaneous dissolution of T 1 phase was kinetically feasible. The T 1 phase generated a larger distortion energy, and the surface energy as well as the internal pressure of T 1 phase increased in dissolving during dynamic loading to increase the free energy difference (driving force for dissolving) between T 1 phase and matrix, making the instantaneous dissolution of the T 1 phases be thermodynamically feasible. The diffusion rates of Cu and Li atoms were significantly accelerated to promote the instantaneous dissolution of T 1 phase particles. The results of the Vickers hardness values showed that the hardness increased after loadings, due to the high density of dislocations and only partial dissolution of the T 1 phase particles. [Display omitted] [ABSTRACT FROM AUTHOR]

The ester sulfonate anionic surfactants are a potentially valuable class of sustainable surfactants. The micellar growth, associated rheological changes, and the onset of precipitation are important consequences of the addition of electrolyte and especially multi-valent electrolytes in anionic surfactants. Small angle neutron scattering, SANS, has been used to investigate the self-assembly and the impact of different valence electrolytes on the self-assembly of a range of ester sulfonate surfactants with subtly different molecular structures. The results show that in the absence of electrolyte small globular micelles form, and in the presence of NaCl, and AlCl 3 relatively modest micellar growth occurs before the onset of precipitation. The micellar growth is more pronounced for the longer unbranched and branched alkyl chain lengths. Whereas changing the headgroup geometry from methyl ester to ethyl ester has in general a less profound impact. The study highlights the importance of relative counterion binding strengths and shows how the surfactant structure affects the counterion binding and hence the micelle structure. The results have important consequences for the response of such surfactants to different operational environments. [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]

• Polysaccharide/protein nanoparticles are studied by small angle neutron scattering. • A three-level hierarchical model describes the internal morphology. • Intermediate and high length scales are enhanced upon thermal treatment. • Scattering from intermediate clusters diminishes upon swelling at neutral pH. • β-Carotene adsorbs at the outer regions of the nanoparticles. We use small angle neutron scattering (SANS) to characterize the internal morphology of nanoparticles (NPs) formed by the complexation between chondroitin sulfate (CS) and bovine serum albumin (BSA) and subsequent stabilization by thermal treatment. We demonstrate that SANS can quantify the internal rearrangements and protein morphology alterations upon thermal treatment and solution conditions variations. A three-level Guinier/power-law hierarchical model identifies BSA globules, interconnected clusters of globules and higher aggregates. The effect of temperature treatment which causes protein denaturation and β-sheet inter-globular associations is captured by the model at the relevant length scales 1–100 nm. Furthermore, the nanogel behavior of the thermally treated CS/BSA NPs, which up to this moment had been characterized by light scattering, is elucidated. Loading of the nutraceutical compound β-carotene (β-C) is revealed to occur at the outer regions of the NPs. This study demonstrates that the combination of SANS and a hierarchical model for data analysis may provide very useful insights for nanocarriers which are based on polysaccharide/protein complexes and aim at biomedical applications and the food industry. [ABSTRACT FROM AUTHOR]

Abstract HKUST-1 is a strictly microporous crystalline metal organic framework with pore sizes of 5, 11, and 13.5 Å. Detailed gas adsorption measurements show that its adsorption capacity for water at 20 °C is higher than that for nitrogen at −196 °C, and far exceeds that for methane at 0 °C. Extended exposure to water vapour at high relative humidity, or consecutive adsorption-desorption cycling of water vapour, destroys both the MOF crystal structure and its adsorption capacity, after a reduced number (<5) of cycles. Destruction proceeds through mesoporous defects that open within the crystal structure, as attested both by the development of hysteresis in the adsorption isotherms and by changes in the small angle X-ray scattering pattern. In the pristine crystal, the structure of the water in the micropores closely resembles that of bulk liquid water. Small angle neutron scattering demonstrates that water is adsorbed preferentially over methane, and that the size of the spherical cavities occupied by the adsorbed water molecules in the intact crystal is consistent with the known pore size structure in this system. Graphical abstract Unlabelled Image Highlights • In pores of fully hydrated HKUST-1, water molecules are in an amorphous state. • Structural damage occurs through dehydration/rehydration cycles. • Five cycles suffice to destroy crystal structure completely. • Damage starts at crystallite surfaces and results in mesoporosity. • Water is preferentially adsorbed over methane (0 °C, 1 bar). [ABSTRACT FROM AUTHOR]

Various studies have shown that food structure has an impact on digestion kinetics. We focus here on the effects of gastric and intestinal enzymes (in-vitro digestion) on two canola seed storage proteins, napin and cruciferin. To monitor structure effect we conducted experiments on gels of these proteins at different pHs, yielding different structures and elastic modulus. What is new is to get information on the mechanisms at the lowest scales, using imaging and radiation scattering at large facilities: Synchrotron fluorescence microscopy, X-Ray scattering, at SOLEIL synchrotron, and Small-Angle Neutron Scattering, at Laboratoire Léon Brillouin reactor. We can identify the mechanisms at each step and in two distinct scale ranges, observed simultaneously, the one of the individual protein scale and the one of the structure connectivity: • during gelation individual canola proteins are not deeply modified in comparison with their state in solution ; larger scale gel heterogeneity appears due to connectivity or aggregation • in the gastric step (up to 40 min): ○ at short scale (large q) we see that the proteins disintegration is much slowed down in gels than in solutions, particularly in the gastric phase; ○ at larger scales (low q), we see that the gel structure is also self-resistant to the action of the enzyme (pepsin). • in the intestinal step, such kinetics differences hold until major disintegration after no more than 15 min. [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]

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]

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]

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]

The synthesis and spectroscopic characterization of task-specific ionic liquid (TSIL) and its surface active properties are depicted in this study. The detailed synthesis protocol for C n PyCl ( n = 4, 6, 8) along with C n PyDs are discussed. The physical properties of ILs including their solubility in various organic solvent are given. The synthesized ILs is characterized by 1 H NMR, IR, MS and thermal methods From the TGA analysis, it found that the stability is increases by replacing anion (Cl − ) by dodecylsulphate of ILs. The C n PyDs has very limited solubility in water, therefore they are making stable micelles and their geometry and size is determined by Small Angle Neutron Scattering (SANS) measurements. We have demonstrated that micellar behaviour of TSIL in water by SANS and surface tension measurements. [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]

We have studied by means of small angle neutron scattering and diffraction, and molecular dynamics simulations the effect of lipid membrane fluidity on the amyloid-beta peptide interactions with the membrane. These interactions have been discovered previously to trigger the reorganization of model membranes between unilamellar vesicles and planar membranes (bicelle-like structures) during the lipid phase transition. The morphology changes were taking place in rigid membranes prepared of fully saturated lipids and were proposed to play a role in the onset of amyloid related disorders. We show in this study that the replacement of fully saturated lipids by more fluid mono-unsaturated lipids eliminates the mentioned morphology changes, most likely due to the absence of phase transition within the temperature range investigated. We have therefore controlled the membrane rigidity also while ensuring the presence of membrane phase transition within the biologically relevant temperatures. It was done by the addition of melatonin and/or cholesterol to the initial membranes made of saturated lipids. Small angle neutron scattering experiments performed over a range of cholesterol and melatonin concentrations show their distinctive effects on the local membrane structure only. The cholesterol for example affects the membrane curvature such that spontaneously formed unilamellar vesicles are of much larger sizes than those formed by the neat lipid membranes or membranes with melatonin added. The temperature dependent experiments, however, reveal no influence on the previously discovered membrane breakage whether cholesterol or melatonin have been added. [Display omitted] • Amyloid-beta peptides incorporated in a lipid membrane trigger its morphological changes. • The membrane breakage takes place during the lipid phase transition. • Additions of melatonin and cholesterol control the membrane rigidity. • Aβ triggered membrane disruptions remain unaffected by cholesterol and melatonin. [ABSTRACT FROM AUTHOR]

We report on the morphological transitions of didodecyldimethylammonium bromide (DDAB) cationic vesicles and hybrid DDAB/hyaluronic acid (HA) vesicles upon addition of BSA at pH 7 where BSA is overall negatively charged. Small angle neutron scattering (SANS) is used to extract the size distributions of the nanovesicles, the thickness of the DDAB bilayers and their lamellarity. Although the HA-decorated DDAB vesicles contain the negatively charged polysaccharide the interaction with BSA appears to be more intense in comparison to bare vesicles. Characteristic peaks in the SANS patterns indicate the presence of multilamellar interfaces while the formation of multilamellar vesicles induced by BSA depends on the amount of added HA. Consequently, higher lamellarities are observed at higher BSA contents. This work demonstrates a simple methodology to tune the encapsulation of globular proteins in vesicular nanoassemblies by affecting their lamellarity and has direct implications on the application of vesicles and liposomes in protein delivery. [Display omitted] [ABSTRACT FROM AUTHOR]

• Coke nanopore numbers increase substantially on heating to 1400 °C and 1600 °C. • The greatest increase is observed in the number of 10 nm-radius pores. • Above 100 nm size, nearly all newly formed pores are open. • Heating at higher temperatures or for longer had greater effects on pore numbers. Small Angle Neutron Scattering and Ultra Small Angle Neutron Scattering were used to study the effect of annealing at temperatures of 1400 and 1600 °C, in an inert atmosphere, on the pore size distribution of three cokes prepared from Australian coals. The pore size range investigated was 1 nm to 2 µm. It was found that annealing substantially changed the size distribution of these pores in similar ways for all three cokes examined, despite the difference in rank and maceral composition of the starting coals. The pore sizes at which the greatest percentage changes in numbers occurred on heating was around 10 nm, with an increase in the number of both open and closed pores, by up to a factor of four after annealing at 1600 °C. For pores in the size range 100 nm to 2 µm, the number of closed pores decreased slightly and the number of open pores increased substantially; new open pores were created. The percentage increase in pore numbers introduced by annealing decreased with increasing pore size above 100 nm, but even at 2 µm pore radius, some samples showed a 50 % increase in total pore numbers. Annealing at greater temperature or longer time had a greater effect on pore numbers. [ABSTRACT FROM AUTHOR]

Effect of electric current on precipitation hardening for advanced high-strength steel is investigated based on mechanical testing and microscopic observation. Complex-phase steel containing nano-sized Nb-bearing carbides was used. By comparing the flow stress between uniaxial tension with applied electric current (pulsed tension) and without electric current (nonpulsed tension) at various elevated temperatures, the influence of electric current on precipitation hardening was confirmed. A higher values of Vickers hardness and full-width-at-half-maximum were obtained in the pulsed tensile specimen compared to the identically heat treated specimen after the same deformation. Small angle neutron scattering analysis showed that the volume fraction and mean diameter of newly formed precipitates in the pulsed tensile specimen were higher and larger than those in the induction heat treated specimen, respectively. It clearly shows that additional precipitation hardening could be induced by the athermal effect of electric current, which is distinct from the thermal effect of Joule heating. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Asphaltene aggregation is a significant issue at every stage of crude oil extraction, processing, transport, and application. • Understanding the phase separation process necessitates structural analysis of asphaltene aggregates. • X-ray diffraction and X-ray/neutron scattering techniques enable analysis of asphaltene colloids at multiple lengthscales and in situ during phase separation. • This article summarises the techniques and models developed, in addition to structural and mechanistic understanding gained from scattering and diffraction methods. Asphaltenes are an important class of complex carbon-rich molecules found in crude oil. Their chemical structure varies depending on the geological source but generally comprises fused aromatic rings, aliphatic substituents and heteroatom functionality, which results in a strong tendency to aggregate and phase separate within crude oil. Asphaltene 'drop-out' owing to phase separation is a major problem spanning crude oil extraction, refining and application. More specifically, the build-up of asphaltene deposits can reduce the permeability of porous rock formations, block oil pipelines, and compromise the efficiency of marine engines. This major technical problem is compounded by the fact that the chemical composition, structure and colloidal behavior of asphaltenes varies significantly depending on the origin of the crude oil and the conditions employed for its refinement. As a result, there has been a concerted effort to (i) understand the morphology of asphaltene dispersions, (ii) identify the underlying mechanism(s) that lead to asphaltene 'drop-out' and hence (iii) design stabilizers to maintain colloid stability and/or minimize 'drop-out'. In principle, imaging techniques can be used to visualize the asphaltene aggregates while light scattering can provide particle size information, but these techniques only provide rather limited structural information. Asphaltene aggregation involves several steps and results in highly hierarchical structures including primary nanoaggregates, clusters, and fractal structures, with characteristic length scales ranging from a few angstroms to several microns. In this review article, the use of small-angle scattering (SAS) and X-ray diffraction (XRD) to characterize asphaltene powders, dispersions and aggregates over the past six decades is summarized. These powerful techniques provide a wealth of structural information about molecular stacking, particle size and morphology, and fractal dimensions. [ABSTRACT FROM AUTHOR]

This investigation is based on the results of the experiments on small angle neutron scattering (neutron wavelength is λ=0.3 nm) and goes into patterning trans-atomic-level structure of hydrated portland cement compositions. The following structural parameters are determined: particle size distribution, porosity, fractal dimensionality. The paper stresses the effect of both artificial (γAl2O3, carbon materials) and technogenic (slurry) nanoagents and nanomodifiers on these structural parameters as well as the effect of complex additives with surface-active agents. [ABSTRACT FROM AUTHOR]

[Display omitted] • Polysorbate T20 and Polysorbate T20-Pluronic P84 mixed micelles accommodates a higher amount of hydrophobic drug Olanzapine. • Isothermal titration calorimetry confirmed the higher binding capacity of Olanzapine with Polysorbate T20. • SANS measurements suggested that the solubilization capacity of Polysorbates is also dependent upon aggregation number. • Both pure Polysorbates and Polysorbate-Pluronic P84 micelles showed the sustained release behavior. • This research output has a wider scope in colloidal chemistry as well as in pharmaceutical industry and manufacturing. Polysorbates and Pluronic polymers are straightforward to use to improve the performance of hydrophobic molecules, however, colloidal systems of these polymers are not fully understood and loading of drug molecules in these Polysorbate micelles rely on a plethora of factors. Thus, it is a laborious task to select the optimal Polysorbate as a drug delivery vehicle. To pave the way for use of Polysorbates, three Polysorbates with different hydrophobicity were selected for oral delivery of the hydrophobic drug Olanzapine (OLZ). At higher concentration, Polysorbate T20 with low hydrophobicity accommodated a higher amount of OLZ than other Polysorbates T40 and T60 with higher hydrophobicity. The effect of mixed micelles of Pluronic P84 and Polysorbate (T20, T40, T60) on solubilization of OLZ was also studied at different concentration ratios and the higher OLZ solubilization was found to be in T20:P84 mixed micelles at 3:2 %w/v concentration ratio. Stronger interactions between OLZ and T20 were noticed with isothermal titration calorimetry (ITC), resulting in the higher OLZ solubilization in these micelles. Dynamic light scattering (DLS) and small angle neutron scattering (SANS) measurements revealed that mixed micelles of Polysorbates are greater in sizes than pure polysorbate micelles and the size decreased after loading of OLZ. Furthermore, SANS measurements suggested that decrease in the aggregation number after OLZ loading promoted the loading capacity of the Polysorbate micelle. Polysorbates micelles exhibited the sustained release behavior in biological relevant media, examined with in vitro dialysis release method. Therefore, it is believed that the finding of this work could be useful in the oral delivery formulations in which Polysorbates and Pluronics are primarily used. [ABSTRACT FROM AUTHOR]

Abstract: In recent years both neutron reflectivity, NR, and small angle neutron scattering, SANS, have been applied to the study of increasingly complex surface and interfacial properties. The methodology and advantages of using these neutron scattering techniques to probe surfaces and interfaces will be briefly outlined. Some recent examples of surfactant, polymer and polymer–surfactant adsorption at the air–water, liquid–solid, and liquid–liquid planar interfaces are highlighted. These are contrasted by some examples of the nature of adsorption on colloidal sol particles and emulsion droplets. [Copyright &y& Elsevier]

Spinodal decomposition mechanism is well-known for producing nanoscale modulated microstructure which is either sponge-like or plate-like. Our recent investigations of a Ti-Nb based titanium alloy have found two kinds of decomposition-induced transitions triggered simultaneously, a microstructural transition from the spongy-like to the plate-like and a crystal structure transition from bcc to hcp via the coupled atomic shear and shuffle mechanism along the Burgers pathway. Here focuses on thermal evolution kinetics of both transitions and their quantitative relations. Small angle neutron scattering profiles reveal that the aging treatments lead to a gradual change from an oval pattern to a butterfly pattern due to the spongy-to-plate microstructural transition. To characterize the crystal transition and its induced habit plane change, we define an ordering parameter from the shear component of the bcc-hcp transition. The results reveal that both follow the well-known power-law approximation with an activation energy of ∼209 kJ/mol, which is identical with diffusion energy of Nb in binary Ti-Nb alloy. However, their time exponential factors are different, about 1/5 for the microstructure growth and 1/16 for the crystal ordering and its induced habit plane change. The former is less than the common 1/3 law of the decomposition mechanism and the nucleation and growth mechanism. Aided by these kinetic equations, the microstructural and chemical parameters can be modeled by the crystal ordering. This provides a new strategy to tune the nanoscale microstructure by this novel spinodal decomposition coupled with a continuous crystal ordering. [Display omitted] [ABSTRACT FROM AUTHOR]