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This article elucidates the dissolution of cellulose from different raw materials in NaOH aqueous solution via the combination of synchrotron-radiation-based SAXS/WAXS characterization. The X-ray measurements probed the mesostructure of the cellulose samples during the freeze-thawing cycle allowing tracking the initial swelling of the structure, the kinetics of disintegration of the cellulose crystallites as well as controlling the final state of the cellulose solution, i.e. presence or absence of cellulose aggregates. The individual SAXS and WAXS measurements were fitted and modelled to enable visualisation and tracking of the changes in the structure in relation to temperature during cooling and warming phases. To further increase the understanding of the parameters affecting dissolution different cellulose samples and solution compositions were considered. For this purpose the effect of increasing the concentration of NaOH and adding Zn2+ has been carefully investigated as well as the importance of the cellulose origin. We found consistent development that the dissolution occurs faster at higher concentrations of NaOH and with Zn2+ regardless the origin. Nevertheless, SAXS data show that materials with a larger amount of cellulose I show more apparent swelling in mesoscopic structure than bleached agricultural containing cellulose II. Despite few crystalline residues after the complete cooling-heating cycle shown by WAXS, some cellulose was not completely dissolved as some network structure remained in the samples under the test condition as suggested by SAXS. [ABSTRACT FROM AUTHOR]

Nanometric precipitates in metallic alloys often have highly anisotropic shapes. Given the large grain size and non‐random texture typical of these alloys, performing small‐ and wide‐angle X‐ray scattering (SAXS/WAXS) measurements on such samples for determining their characteristics (typically size and volume fraction) results in highly anisotropic and irreproducible data. Rotations of flat samples during SAXS/WAXS acquisitions are presented here as a solution to these anisotropy issues. Two aluminium alloys containing anisotropic precipitates are used as examples to validate the approach with a −45°/45° angular range. Clear improvements can be seen on the SAXS I(q) fitting and the consistency between the different SAXS/WAXS measurements. This methodology results in more reliable measurements of the precipitate's characteristics, and thus allows for time‐ and space‐resolved measurements with higher accuracy. [ABSTRACT FROM AUTHOR]

The efficient use of softwood in biorefineries requires harsh pretreatment conditions to overcome biomass recalcitrance. Following harsh pretreatments, the hemicellulose is solubilized. Here, we studied the material characteristics of Norway spruce following steam pretreatment at six different severities, relating chemical and structural information to the enzymatic hydrolyzability. Steam pretreatment conditions were defined by two different temperatures (180 °C and 210 °C), with and without the addition of various acids (CH3COOH, H3PO4, H2SO4, SO2). Structural knowledge of the streams is a cornerstone for developing an efficient saccharification process. This study combines advanced structural characterizations to gain fundamental understanding of the influence of severity of pretreatment on spruce. Structural knowledge is a cornerstone in developing an effective saccharification process by modulating pretreatment conditions and enzymes employed. Overall structural properties were assessed by scanning electron microscopy. The effect of stream pretreatment severity on lignin and lignin-carbohydrate bonds was investigated by two-dimensional heteronuclear single quantum correlation nuclear magnetic resonance. Finally, cellulose ultrastructure was studied by applying small/wide-angle X-ray scattering. The structural characteristics of the six pretreated softwood substrates were related to the enzymatic hydrolyzability. With increasing pretreatment severity, surface defibrillation, and lignin depolymeryzation were observed. Further, lignin-carbohydrate complexes signals were detected. Cellulose analysis revealed the rearrangement of microfibrils leading to the formation of larger microfibril aggregates. This microfibril rearrangement likely contributed to the observed increase in enzymatic hydrolysis yields as better enzyme accessibility resulted. [ABSTRACT FROM AUTHOR]

Preparation of biomacromolecules for structural biology studies is a complex and time‐consuming process. The goal is to produce a highly concentrated, highly pure product that is often shipped to large facilities with tools to prepare the samples for crystallization trials or for measurements at synchrotrons and cryoEM centers. The aim of this article is to provide guidance and to discuss general considerations for shipping biomacromolecular samples. Details are also provided about shipping samples for specific experiment types, including solution‐ and cryogenic‐based techniques. These guidelines are provided with the hope that the time and energy invested in sample preparation is not lost due to shipping logistics. [ABSTRACT FROM AUTHOR]

Benefiting from the development of high‐brilliance synchrotron radiation sources, microbeam X‐ray scattering has become a well established scattering‐based imaging technology. This article describes the newly constructed time‐resolved microbeam small‐angle X‐ray scattering (µSAXS) experimental station at the BL10U1 beamline at the Shanghai Synchrotron Radiation Facility. The µSAXS endstation provides SAXS/WAXS measurements with a 10 µm hard X‐ray beam and a flux of ∼1012 photons s−1. A multi‐axis sample stage, an on‐axis viewer and in situ experimental apparatus are incorporated to facilitate multi‐method scientific experiments in various material fields. As scientific examples, this article explores 1D tomography, 2D mapping and tomographic sectioning based on X‐ray scattering to investigate the micro–nanostructures of polymer fiber, spherulite and bamboo samples. [ABSTRACT FROM AUTHOR]

The clinical benefits of using exogenous pulmonary surfactant (EPS) as a carrier of budesonide (BUD), a non-halogenated corticosteroid with a broad anti-inflammatory effect, have been established. Using various experimental techniques (differential scanning calorimetry DSC, small- and wide- angle X-ray scattering SAXS/WAXS, small- angle neutron scattering SANS, fluorescence spectroscopy, dynamic light scattering DLS, and zeta potential), we investigated the effect of BUD on the thermodynamics and structure of the clinically used EPS, Curosurf®. We show that BUD facilitates the Curosurf® phase transition from the gel to the fluid state, resulting in a decrease in the temperature of the main phase transition (Tm) and enthalpy (ΔH). The morphology of the Curosurf® dispersion is maintained for BUD < 10 wt% of the Curosurf® mass; BUD slightly increases the repeat distance d of the fluid lamellar phase in multilamellar vesicles (MLVs) resulting from the thickening of the lipid bilayer. The bilayer thickening (~0.23 nm) was derived from SANS data. The presence of ~2 mmol/L of Ca2+ maintains the effect and structure of the MLVs. The changes in the lateral pressure of the Curosurf® bilayer revealed that the intercalated BUD between the acyl chains of the surfactant's lipid molecules resides deeper in the hydrophobic region when its content exceeds ~6 wt%. Our studies support the concept of a combined therapy utilising budesonide—enriched Curosurf®. [ABSTRACT FROM AUTHOR]

X‐rays are a penetrating form of high‐energy electromagnetic radiation with wavelengths ranging from 10 pm to 10 nm. Similar to visible light, X‐rays provide a powerful tool to study the atoms and elemental information of objects. Different characterization methods based on X‐rays are established, such as X‐ray diffraction, small‐ and wide‐angle X‐ray scattering, and X‐ray‐based spectroscopies, to explore the structural and elemental information of varied materials including low‐dimensional nanomaterials. This review summarizes the recent progress of using X‐ray related characterization methods in MXenes, a new family of 2D nanomaterials. These methods provide key information on the nanomaterials, covering synthesis, elemental composition, and the assembly of MXene sheets and their composites. Additionally, new characterization methods are proposed as future research directions in the outlook section to enhance understanding of MXene surface and chemical properties. This review is expected to provide a guideline for characterization method selection and aid in precise interpretation of the experimental data in MXene research. [ABSTRACT FROM AUTHOR]

We communicate a feasibility study for high‐resolution structural characterization of biomacromolecules in aqueous solution from X‐ray scattering experiments measured over a range of scattering vectors (q) that is approximately two orders of magnitude wider than used previously for such systems. Scattering data with such an extended q‐range enables the recovery of the underlying real‐space atomic pair distribution function, which facilitates structure determination. We demonstrate the potential of this method for biomacromolecules using several types of cyclodextrins (CD) as model systems. We successfully identified deviations of the tilting angles for the glycosidic units in CDs in aqueous solutions relative to their values in the crystalline forms of these molecules. Such level of structural detail is inaccessible from standard small angle scattering measurements. Our results call for further exploration of ultra‐wide‐angle X‐ray scattering measurements for biomacromolecules. [ABSTRACT FROM AUTHOR]

Conductive fibers are needed for the development of flexible electronic and biomedical devices. MXene fibers show great promise for use in such applications because of their high conductivity. Current literature on MXene fiber development highlights the need for improving their mechanical properties and investigation of biocompatibility. Here the use of silk fibroin biopolymer as a MXene formulation additive for the production of MXene fibers is studied. It is found that the favorable silk fibroin–MXene interactions resulted in improved durability, withstanding up to 1 h of high frequency sonication in buffered solutions. Furthermore, fibers with ≈5 wt% silk fibroin displays interesting properties including high conductivity (≈3700 S cm−1), high volumetric capacitance (≈910 F cm−3), and non‐cytotoxicity toward THP‐1 monocytic cells. The results presented here provide an important insight into potential use of MXene fibers in flexible electronics and biomedical applications. [ABSTRACT FROM AUTHOR]

This work describes the instrumentation and software for microbeam scattering and structural mapping at the Life Science X-ray Scattering (LiX) beamline at NSLS-II. Using a two-stage focusing scheme, an adjustable beam size between a few micrometres and a fraction of a millimetre is produced at the sample position. Scattering data at small and wide angles are collected simultaneously on multiple Pilatus detectors. A recent addition of an in-vacuum Pilatus 900k detector, with the detector modules arranged in a C-shaped configuration, has improved the azimuthal angle coverage in the wide-angle data. As an option, fluorescence data can be collected simultaneously. Fly scans have been implemented to minimize the time interval between scattering patterns and to avoid unnecessary radiation damage to the sample. For weakly scattering samples, an in-vacuum sample environment has been developed here to minimize background scattering. Data processing for these measurements is highly sample-specific. To establish a generalized data process workflow, first the data are reduced to reciprocal coordinates at the time of data collection. The users can then quantify features of their choosing from these intermediate data and construct structural maps. As examples, results from in-vacuum mapping of onion epidermal cell walls and 2D tomographic sectioning of an intact poplar stem are presented.

Abstract Conductive fibers are needed for the development of flexible electronic and biomedical devices. MXene fibers show great promise for use in such applications because of their high conductivity. Current literature on MXene fiber development highlights the need for improving their mechanical properties and investigation of biocompatibility. Here the use of silk fibroin biopolymer as a MXene formulation additive for the production of MXene fibers is studied. It is found that the favorable silk fibroin–MXene interactions resulted in improved durability, withstanding up to 1 h of high frequency sonication in buffered solutions. Furthermore, fibers with ≈5 wt% silk fibroin displays interesting properties including high conductivity (≈3700 S cm−1), high volumetric capacitance (≈910 F cm−3), and non‐cytotoxicity toward THP‐1 monocytic cells. The results presented here provide an important insight into potential use of MXene fibers in flexible electronics and biomedical applications.

Bamboo is a swiftly renewable natural material. A thorough exploration of its functional hierarchical structure is helpful to improve its utilization efficiency. Previous studies have found that there are notable structural distinctions in bamboo fibers and parenchyma cell wall at the nanoscale. The fluctuation in cellulose microfibrils (CMF) within bamboo has been verified as a critical factor significantly impacting the mechanical properties of bamboo fibers. This study systematically examines the radial gradient variation in the cellulose supramolecular structures of bamboo culms through synchrotron X-ray scattering. The measured cellulose crystallinity index (CrI), the diameter and packing distance of CMF, the orientation parameter, and the distribution of microfibril angle (MFA) were found to be correlated with the radial distribution of fibers and parenchyma cells. In the radial direction, the relative CrI values of 004 reflection increased from 26 % for the innermost layer to 51 % for the outermost layer; the CMF diameter decreased from 2.75 nm to 2.66 nm; the packing distance of CMF' cylinders was reduced from 3.68 nm to 3.35 nm. The measured mean MFA values exhibit a decrease from approximately 70° to around 5°. Moreover, the azimuthal X-ray scattering signals were effectively segregated from fiber and parenchyma cell wall using the non-negative matrix factorisation (NNMF) method. This methodology holds promise for nanostructure analysis in complex plant stems comprising fiber and parenchyma cells, including but not limited to wheat, corn stalks, and other biomaterials. • Investigate radial gradient nanostructure of CMFs in bamboo by X-ray Scattering. • Separate azimuthal X-ray scattering signals of fiber/parenchyma cells using NNMF. • Organization of bamboo CMFs obtained from SAXS by fitting with WoodSAS model.. [ABSTRACT FROM AUTHOR]

Ti3C2Tx MXene (or "MXene" for simplicity) has gained noteworthy attention for its metal‐like electrical conductivity and high electrochemical capacitance—a unique blend of properties attractive toward a wide range of applications such as energy storage, healthcare monitoring, and electromagnetic interference shielding. However, processing MXene architectures using conventional methods often deals with the presence of defects, voids, and isotropic flake arrangements, resulting in a trade‐off in properties. Here, a sequential bridging (SB) strategy is reported to fabricate dense, freestanding MXene films of interconnected flakes with minimal defects, significantly enhancing its mechanical properties, specifically tensile strength (≈285 MPa) and breaking energy (≈16.1 MJ m–3), while retaining substantial values of electrical conductivity (≈3050 S cm–1) and electrochemical capacitance (≈920 F cm–3). This SB method first involves forming a cellulose nanocrystal‐stitched MXene framework, followed by infiltration with structure‐densifying calcium cations (Ca2+), resulting in tough and fatigue resistant films with anisotropic, evenly spaced, and strongly interconnected flakes — properties essential for developing high‐performance energy‐storage devices. It is anticipated that the knowledge gained in this work will be extended toward improving the robustness and retaining the electronic properties of 2D nanomaterial‐based macroarchitectures. [ABSTRACT FROM AUTHOR]

Perfluorosulfonic-acid (PFSA) membranes are widely used as the solid electrolyte in electrochemical devices where their main functionalities are ion (proton) conduction and gas separation in a thermomechanically stable matrix. Due to prolonged operational requirements in these devices, PFSA membranes' properties change with time due to hygrothermal aging. This paper studies the evolution of PFSA structure/property relationship changes during hygrothermal aging, including chemical changes leading to changes in ion-exchange capacity (IEC), nanostructure, water-uptake behavior, conductivity, and mechanical properties. Our findings demonstrate that with hygrothermal aging, the storage modulus increases, while IEC and water content decrease, consistent with the changes in nanostructure, that is, water- and crystalline-domain spacings inferred from small- and wide-angle X-ray scattering (SAXS/WAXS) experiments. In addition, the impact of aging is found to depend on the membrane's thermal prehistory and post-treatments, although universal correlations exist between nanostructural changes and water uptake. The findings have impact on understanding lifetime, durability, and use of these and related polymers in various technologies.

This work describes the instrumentation and software for microbeam scattering and structural mapping at the Life Science X‐ray Scattering (LiX) beamline at NSLS‐II. Using a two‐stage focusing scheme, an adjustable beam size between a few micrometres and a fraction of a millimetre is produced at the sample position. Scattering data at small and wide angles are collected simultaneously on multiple Pilatus detectors. A recent addition of an in‐vacuum Pilatus 900k detector, with the detector modules arranged in a C‐shaped configuration, has improved the azimuthal angle coverage in the wide‐angle data. As an option, fluorescence data can be collected simultaneously. Fly scans have been implemented to minimize the time interval between scattering patterns and to avoid unnecessary radiation damage to the sample. For weakly scattering samples, an in‐vacuum sample environment has been developed here to minimize background scattering. Data processing for these measurements is highly sample‐specific. To establish a generalized data process workflow, first the data are reduced to reciprocal coordinates at the time of data collection. The users can then quantify features of their choosing from these intermediate data and construct structural maps. As examples, results from in‐vacuum mapping of onion epidermal cell walls and 2D tomographic sectioning of an intact poplar stem are presented. [ABSTRACT FROM AUTHOR]

The influence of alpha-cyclodextrin (αCD) on PEG crystallization is examined for a peptide-PEG conjugate, YYKLVFF-PEG3k comprising an amyloid peptide YYKLVFF linked to PEG with molar mass 3 kg mol -1 . Remarkably, differential scanning calorimetry (DSC) and simultaneous synchrotron small-angle/wide-angle X-ray scattering (SAXS/WAXS) show that crystallization of PEG is suppressed by αCD, provided that the cyclodextrin content is sufficient. A hexagonal mesophase is formed instead. The αCD threading reduces the conformational flexibility of PEG, and hence suppresses crystallization. These results show that addition of cyclodextrins can be used to tune the crystallization of peptide-polymer conjugates and potentially other polymer/biomolecular hybrids., (© 2024 The Authors. ChemBioChem published by Wiley-VCH GmbH.)

Hockey-stick-shaped liquid crystals are interesting due to their unusual physical properties. Nematic phase observed in these materials have shown promising ferroelectric-like switching, ease of alignment in a planar and homeotropic cell, large flexoelectricity, etc. Polar moieties viz. F, Cl, NO2, etc., in their molecular architecture lead to the development of permanent dipole moment which in turn affects the phase structure and physical properties. Herein, we have designed and synthesised a new series of four-ring-based hockey-stick-shaped molecules having polar Cl group at one end and variable aliphatic chains at another end of the molecular long axis. The four phenyl rings are attached via one ester and two imine linkages. All the compounds exhibited enantiotropic mesomorphism. The lower homologs (1–5 to 1–8) exclusively showed nematic phase whereas other higher homologs either exhibited nematic and/or smectic A phase. Compound 1–5 showed a stable nematic phase with the highest phase range of about 110 °C upon cooling. Detailed X-ray diffraction revealed the internal arrangement of molecules in layers. Density functional theory study confirmed the resultant dipole moment of the molecules (approximately 6 Debye) which in turn cancelled out in the bulk phase due to preferable antiparallel arrangement as a dimer. [ABSTRACT FROM AUTHOR]

The outstanding electrical conductivity and high specific capacitance of 2D Ti3C2Tx MXene have made them promising materials for a wide range of applications including wearable electronics, energy storage, sensors, and electromagnetic interference shielding. However, the fabrication of MXene architectures, both pure and composite, often results in a trade‐off in properties. Here, it is reported that sequential bridging of MXene sheets significantly enhances the mechanical properties of its free‐standing films, with improvements in strength and toughness of up to ≈339 MPa and ≈12.0 MJ m−3, respectively, while simultaneously retaining both high conductivity (≈4850 S cm−1) and volumetric capacitance (≈1220 F cm−3). This sequential bridging strategy permits surface modification of MXene sheets while still yielding stable colloidal dispersions so that the subsequent MXene films comprise of aligned, evenly‐spaced, and interconnected sheets, which are critical for the development of robust energy storage devices and other high performance applications. [ABSTRACT FROM AUTHOR]

We present a small angle X-ray scattering (SAXS) study of the colloidal structure of regenerated cellulose fibers, air-gap spun from an ionic liquid solution. Based on the data, and a different interpretation of the anisotropic SAXS pattern, we propose a slightly different colloidal structure of the fibers, than what is commonly assumed for regenerated cellulose fibers. Fibers with two different degrees of orientation, as produced by different draw ratios, DR = 2 and 15, respectively, are analyzed. The 2D SAXS pattern is highly anisotropic with striking cross-like pattern, having scattering predominantly perpendicular and parallel to the fiber axis. This cross-like pattern suggest a colloidal structure with oriented crystalline lamellae of ca. 10 nm thickness, embedded within a continuous matrix of amorphous cellulose. The lamellae are oriented with their normal parallel with the fiber axis. Complementary wide angle X-ray diffraction data confirm that the lamellae normal direction corresponds to the cellulose chain direction (c-direction) in the monoclinic cellulose crystal (Cellulose II). [ABSTRACT FROM AUTHOR]

The drying of colloidal dispersions is a dynamic area that has many practical applications across a wide range of sectors. While most research focuses on the drying patterns formed after desiccation and the physical-chemical parameters that influence this process, the structure formed as a result of particle accumulation has received comparatively far less attention. In this work, an investigation of the structure formed after the drying of a 4% w/w Laponite - NaCl dispersion, with ionic force I = 10 − 3 M , in a confined geometry between two hydrophilic mica windows was performed. The desiccation was characterized by measuring the mass of the dispersion over time, until no further mass loss was detected. The sample shrank to the middle of the sample holder, and SAXS/WAXS experiments were conducted after complete drying to better understand the structure formed. Such experiments revealed the formation of clusters with various sizes, shapes, and anisotropic orientations, as well as the formation of structures with different crystalline orders that were not present in the initial sample. These structures were all quantified and interpreted on the basis of Laponite interparticle interactions, possible structured water that remained inside the dried sample even after drying ceased, and NaCl crystallization. Finally, the macroscopic consequence of the microstructure formed was observed in photographs using polarized optical microscopy. The results provided a better comprehension of the structure formed in concentrated Lap dispersions before as well as after drying, showing that X-ray scattering techniques can be useful to investigate the drying of a variety of other colloidal systems. [Display omitted] • Desiccation led to unique particle accumulation due to confined geometry. • Clusters with different sizes, shape and anisotropic orientations • Coexistence of two structures with different structured order • SAXS is a feasible technique to understand the drying of colloidal systems. [ABSTRACT FROM AUTHOR]

All-inorganic cesium lead halide perovskite nanocrystals (NCs) have received much attention due to their outstanding optical and electronic properties, but the underlying growth mechanism remains elusive due to their rapid formation process. Here, we report an in situ real-time study of the growth of Cs 4 PbBr 6 NCs under practical synthesis conditions in a custom-made reactor. Through the synchrotron-based small-angle X-ray scattering technique, we find that the formation of Cs 4 PbBr 6 NCs is accomplished in three steps: the fast nucleation process accompanied by self-focusing growth, the subsequent diffusion-limited Ostwald ripening, and the self-assembly of NCs into the face-centered cubic (fcc) superlattices at high temperature and the termination of growth. The simultaneously collected wide-angle X-ray scattering signals further corroborate the three-step growth model. The influence of superlattice formation is also elucidated, which improves the uniformity of the final NCs.

Abstract In this study, curcumin was encapsulated within electrospun protein (i.e. gelatin and zein) fibers to generate bioactive coatings for food packaging. Additionally, a green tea extract (GTE) was also incorporated within the formulations to evaluate its impact on the stability, protective ability, and release properties of the curcumin-loaded fibers. Due to the poor solubility of curcumin in aqueous media, a strategy based on its incorporation through liposomes was developed, allowing to successfully incorporating curcumin into gelatin fibers. Very high encapsulation efficiencies were attained for both zein and gelatin, with the former showing an enhanced protection effect and a more limited and slower release of the curcumin in hydrophobic food simulants. The addition of GTE resulted in strong interactions being established with the proteins and, in the particular case of gelatin, it improved the protective effect and slowed down the curcumin release from the fibers, although it did not prevent their collapse in water. The results showed that while the developed gelatin coatings showed a promising release behavior in contact with fatty food simulants, zein-based coatings would be more adequate for packaging of high water content food products. Graphical abstract Image Highlights • Curcumin-containing protein-based coatings were developed through electrospinning. • The effect of addition of an antioxidant extract to the formulations was evaluated. • High encapsulation efficiencies and enhanced curcumin protection were attained. • The antioxidant extract improved protection and modified the release. • Selection of the protein matrix needs to be done depending on final application. [ABSTRACT FROM AUTHOR]

This work provides an in-depth analysis on how the addition of different microalgae species ( Nannochloropsis , Spirulina and Scenedesmus ) affected the structural and physicochemical properties of thermoplastic corn starch biocomposites. Structural characterization was conducted by combined SAXS/WAXS experiments and it was correlated with mechanical and barrier properties of the biocomposites. A water vapour permeability drop of ca . 54% was observed upon addition of the different microalgae species. The oxygen permeability and the mechanical properties of biocomposites containing Spirulina or Scenedesmus were not improved since the presence of microalgae hindered the re-arrangement and packing of the lamellar structure of starch polymeric chains, according to the SAXS results. Nannochloropsis caused a great reduction of the matrix rigidity and, the oxygen permeability was also improved. Therefore, all of these features make the Nannochloropsis biocomposites an alternative to generate biodegradable food packaging materials with the additional advantage that they can be easily scaled-up. [ABSTRACT FROM AUTHOR]

The mechanical behaviour, crystalline and macromorphology structure development during uniaxial deformation and annealing of poly- l -lactic acid (PLLA), with varying strain rate and draw temperatures ( T d ) above T g , have been investigated using small- and wide-angle X-ray scattering (SAXS/WAXS), microscopy, thermal and mechanical techniques. The mechanical behaviour of PLLA, was strongly dependent on T d where embrittlement and eventual failure were observed as T d was increased, during uniaxial drawing of the amorphous polymer. This was mirrored in the bulk surface morphology where crazing, microvoiding and cavitation occurred with increasing T d . SAXS/WAXS data showed that strain-induced crystallization occurs on drawing, but crystallite orientation decreased with increasing T d , due to chain relaxation at temperatures ≥30 °C above T g . However, no long-range oriented lamellar macromorphology was observed post-draw directly and only developed in the samples that were step annealed at temperatures above T d . Also, the disordered α′ crystal form was observed post-draw at T d between 60 and 80 °C, whereas T d  ≥ 90 °C, resulted in the ordered α crystal form directly. However, on annealing at temperatures of ≥110 °C, the α′-α crystal transition ensued and in all samples, an oriented lamellar macromorphology developed. Therefore, T d and post-draw annealing, have a significant influence on the mechanical properties, crystallinity and crystalline phase transformation in PLLA, which in-turn, affects the polymers medical and industrial applications. [ABSTRACT FROM AUTHOR]

Films obtained by casting, starting from conventional emulsions (CE), nanoemulsions (NE) or their gels, which led to different structures, with the aim of explore the relationship between structure and physical properties, were prepared. Sodium caseinate was used as the matrix, glycerol as plasticizer, glucono-delta-lactone as acidulant to form the gels, and TiO 2 nanoparticles as reinforcement to improve physical behavior. Structural characterization was performed by SAXS and WAXS (Small and Wide Angle X-ray Scattering, respectively), combined with confocal and scanning electron microscopy. The results demonstrate that the incorporation of the lipid phase does not notably modify the mechanical properties of the films compared to solution films. Films from NE were more stable against oil release than those from CE. Incorporation of TiO 2 improved mechanical properties as measured by dynamical mechanical analysis (DMA) and uniaxial tensile tests. TiO 2 macroscopic spatial distribution homogeneity and the nanostructure character of NE films were confirmed by mapping the q-dependent scattering intensity in scanning SAXS experiments. SAXS microscopies indicated a higher intrinsic homogeneity of NE films compared to CE films, independently of the TiO 2 load. NE-films containing structures with smaller and more homogeneously distributed building blocks showed greater potential for food applications than the films prepared from sodium caseinate solutions, which are the best known films. [ABSTRACT FROM AUTHOR]

• Multi-synthesized methods of CTAB coated CeO 2 (CTAB@CeO 2) nanoparticles (NPs) characterized with 13 – 16 nm core and 2 – 5 nm CTAB shield;. • SAXS/WAXS spectra and demonstrate the dispersed status and crystallinity of CTAB@CeO 2 NPs in low q range;. • CTAB based Ureax-CeO 2 slurry has better material efficacy (Ra) on 8-inch silica wafer planarization by CMP process;. • Silica wafer planarize with CTABx-CeO 2 NPs reduced the ISO grade number from level 9 to 7, which corresponds to a 70.7–74.5% roughness planarization. Chemical-mechanical planarization (CMP) is the most important process in the semiconductor industry, as it affects the product manufacturing yield. Of the several factors involved in planarization, the choice of abrasive slurries affects the extent to which impurities and roughness are removed. Cerium oxide (CeO 2) is considered an outstanding polishing material because of its excellent hardness, well-controlled structure, and chemical force, and CMP requires well-dispersed slurry nanoparticles (NPs) with uniform structure, size, and shape. In this study, urea/alkaline-induced nanocubic CeO 2 was synthesized in the presence of cationic surfactant cetyltrimethylammonium bromide (CTAB)-generated cubic CeO 2 NPs, which were then used in a silica wafer polishing test. Dynamic laser scattering and transmission electron microscopy indicated that the cubic plate NP size distribution and zeta potential ranged from 18 to 30 nm when measured between –35 and –45 mV. Elemental composition via X-ray photoelectron spectroscopy was studied to demonstrate the mechanism of Ce3+/Ce4+ with crystal information, which matched the X-ray diffraction grain size calculation and finite element–scanning electron microscopy measurements. We also performed a simulation of cubic CeO 2 NP formation and pillar CeO 2 inhibition under an additional amount of structure-modifying agent (e.g., CTAB). Fourier transform infrared spectra indicated a successful CTAB reaction with CeO 2. Small angle X-ray scattering spectra were used to obtain simulated NP shapes and parameters via the SasView model. A confocal laser scanning microscope was then used to measure the roughness and 2-D plane view of an 8-inch tetraethyl orthosilicate coated silica wafer. Our results showed that the bared silica wafer planarize with CTABx-CeO 2 NPs reduced the ISO grade number from Level 9 to Level 7, which corresponds to a 70.7–74.5% roughness planarization of the raw material. This study presents a fast, uniform, low-roughness CMP slurry material synthesis and characterization method that can enhance the technique of slurry nanoparticle synthesis from stable materials. [Display omitted] [ABSTRACT FROM AUTHOR]

Melting of native tapioca starch granules in aqueous pastes upon heating is observed in situ using simultaneous small- and wide-angle X-ray scattering (SAXS/WAXS) and solution viscometry. Correlated structure and viscosity changes suggest closely associated amylose and amylopectin chains in the semicrystalline layers, and the release of amylose chains for enhanced solution viscosity occurs largely after melting of the semicrystalline structure. Before melting, WAXS results reveal mixed crystals of A- and B-types (∼4:1 by weight), whereas SAXS results indicate that the semicrystalline layers are composed of lamellar blocklets of ca 43 nm domain size, with polydisperse crystalline (≃7.5 nm) and amorphous (≃1.1 nm) layers alternatively assembled into a lamellar spacing of ≃8.6 nm with 20% polydispersity. Upon melting, the semicrystalline lamellae disintegrate into disperse and molten amylopectin nanoclusters with dissolved and partially untangled amylose chains in the aqueous matrix which leads to increased solution viscosity. During subsequent cooling, gelation starts at around 347 K; successively increased solution viscosity coincides with the development of nanocluster aggregation to a fractal dimension ≃2.3 at 303 K, signifying increasing intercluster association through collapsed amylose chains owing to decreased solvency of the aqueous medium with decreasing temperature.

The structural information contained in solution scattering data from empty lipid nanodiscs is examined in the context of a multi‐component geometric model. X‐ray scattering data were collected on nanodiscs of different compositions at scattering vector magnitudes up to 2.0 Å−1. Through the calculation of the partial form factor for each of the nanodisc components before the isotropic average, structural parameters in the model were correlated to the features observed in the X‐ray scattering data and to the corresponding distance distribution function. It is shown that, in general, the features at ∼0.3–0.6 Å−1 in the scattering data correlate to the bilayer structure. The data also support the argument that the elliptical shape of nanodiscs found in model fitting is physical, rather than an artefact due to the nanodisc size distribution. The lipid chain packing peak at ∼1.5 Å−1 is visible in the data and reflects the lipid bilayer phase transition. The shape change in the distance distribution function across the phase transition suggests that the nanodiscs are more circular in the fluid phase. The implication of these findings for model fitting of empty and protein‐loaded nanodiscs is discussed. [ABSTRACT FROM AUTHOR]

The morphology in terms of the ion channel size, apparent porosity and tortuosity of perfluorosulfonated membranes was modified by using sulfonated polystyrene (SPS) as a sacrificial porogen. The precursor polymers were fabricated via solution-casting of the commercially available Nafion solution together with SPS. Upon swelling SPS was leached from the membrane matrix resulting in the formation of larger nanosized ion channels and clusters and hence a more open membrane matrix in fully hydrated conditions. Below a threshold value of 30% SPS, the membranes maintained high permselectivity and the porogen mainly increased the apparent porosity and network interconnectivity resulting in increased hydraulic permeability, streaming potential coefficient and membrane conductivity. Higher porogen contents resulted in larger characteristic hydrophilic domain sizes, quantified from SAXS/WAXS, and enhanced membrane conductivity up to 300% with only a slight decrease in the permselectivity in dilute LiCl solutions. These results together confirm the effective modification of the charged nanoscopic ion network and clearly indicate that SPS can efficiently be used for precise tuning the PTFE-based membrane matrix to achieve tailored transport properties for specific electrochemical applications. [ABSTRACT FROM AUTHOR]

This work is aimed at evaluating the ability of the microalgae to partially substitute biodegradable materials with improved physicochemical properties. To this end, starch films containing the microalga Nannochloropsis gaditana sp. ( N. gaditana ) have been developed and characterized. Initially, different ultrasound treatments were evaluated for microalgae cell wall disruption. Although surfactant-aided sonication was the most efficient disruption method, the presence of the surfactant hampered continuous film formation. Subsequently, the ability of intact and ultrasound-treated N. gaditana cells to improve barrier properties of starch films was evaluated. Combined small and wide angle X-ray scattering experiments (SAXS/WAXS, respectively) evidenced slight nanostructural and crystallinity changes induced by the presence of N. gaditana cells. Incorporation of intact or ultrasound-treated microalgae into starch led to more hydrophobic films, with enhanced barrier properties for most of the formulations. However, the films containing the microalgae treated with the greatest ultrasound intensity, did not show any barrier improvement due to the plasticization promoted by the cell components (probably lipids) released during the ultrasound treatment, as suggested by SAXS/WAXS and the mechanical properties. [ABSTRACT FROM AUTHOR]

The properties of gels from amaranth ( Amaranthus cruentus) and achira ( Canna edulis) starch blends at different proportions (75/25, 50/50 and 25/75) in excess (95% water/5% solids) and limited (60% water/40% solids) of water were characterized by textural profile analysis (TPA), paste properties and X-ray scattering. In TPA, the springiness was higher at 5% solids due to a major leaching of amylose. At 40% solids, the hardness, cohesiveness, springiness and adhesiveness values did not correspond to the proportion of each starch in the blend, modifying the textural parameters. This behavior could be related to the incomplete gelatinization, limited amylose leaching and poor gel conformation due to granule size differences and water competition between both starches. The botanical source and water content determine the granular and/or molecular interactions between starches. Using blends allows decrease the granular swelling and the amylose leaching as observed in some modified starches gels. [ABSTRACT FROM AUTHOR]

Intelligent drug-delivery systems are considered one of the most important techniques for improving cancer treatment using existing over-the-counter medicines. However, metallic materials are always accompanied by metabolism problems, whereas chemotherapy produces several side effects in humans. Carbon-based materials exhibit exceptional features such as bio-affinity and bio-degradability. Herein, hollow mesoporous carbon nanoparticles (HMCs) are reported as effective nanocarriers of anti-cancer small drug molecules. Near IR (NIR) sources, which can penetrate most organs, induce thermal effects via non-invasive pathways. NIR radiation not only provides thermal therapy but also is compatible with temperature-sensitive coated responsive polymer shells. The template method was used to synthesize HMCs with size 200 ± 50 nm, under various conditions, to obtain suitably sized and hollow structures for liver-cancer treatment. Additional pH/thermal-bi-responsive poly(N-isopropylacrylamide) (PNIPAM) shells were further coated onto the HMCs to produce multiple shells that could trigger swelling motions in PNIPAM@HMCs, as confirmed via small-angle X-ray scattering (SAXS). NIR results demonstrated an extreme increase to the ∆T of 8.7 and 14.2 °C for HMC and PNIPAM@HMCs, respectively. The SAXS spectra analyzed using SasView simulations demonstrated the multi-shell structures of synthesized HMCs and the release mechanism of PNIPAM@HMCs. Based on the model simulation of SAXS, the different rates of polymer swelling indicated the core shrinkage (229.7 to 134.2 Å) and shell expansion (324.3 to 514.3 Å) at 37 °C and 42 °C, respectively. In addition, the first-order, Higuchi, Korsmeyer-Peppas, and Weibull mathematical models were used to verify the drug-release kinetics, and the model with the highest R 2 value was considered most suitable for further application. This paper presents the first SAXS study on PNIPAM@HMCs release kinetics and related mechanisms. This phenomenon indicates NIR-induced PNIPAM@HMCs as an effective strategy for cancer treatment via doxorubicin release., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Bioinspired in vitro collagen mineralization experiments have been performed in the presence of citrate and the combined role of the two bone organic matrix components in controlling mineral formation was investigated for the first time. Mineralized and non-mineralized collagen fibrils have been in depth characterized by combining small- and wide-angle X-ray scattering (SAXS/WAXS) techniques with Atomic Force Microscopy (AFM) imaging. A synergic effect of collagen and citrate in driving the formation of long-term stable amorphous calcium phosphate (ACP) nanoparticles with platy morphology was found. AFM images on mineralized collagen fibrils revealed that some of the ACP nanoparticles were deposited on the intramolecular nanoscopic holes of collagen fibrils. Statement of Significance Citrate is an important component of the bone organic matrix but its specific role in bone mineralization is presently unclear. In this work, bioinspired in vitro collagen mineralization experiments in the presence of citrate have been carried out and the combined role of collagen and citrate in controlling mineral formation has been addressed for the first time. Through X-ray scattering and Atomic Force Microscopy characterizations on mineralized and non-mineralized collagen fibrils, we have found that citrate in synergy with collagen stabilizes an amorphous calcium phosphate (ACP) phase with platy morphology over one week and controls its deposition on collagen fibrils. [ABSTRACT FROM AUTHOR]

Perfluorosulfonic-acid (PFSA) ionomer membranes (most commonly Nafion®) are currently the prototypical proton-exchange-membrane in polymer-electrolyte fuel cells (PEFCs), for which durability still represents a technical barrier to their commercialization. In an effort to address the durability demands, PFSA membranes with reinforcement and/or stabilizers have become of great interest as they have demonstrated superior durability in PEFCs compared to their unreinforced analogues. One such particular membrane that is tailored for enhanced durability and commonly employed in PEFCs is Nafion XL, a Nafion-based ionomer membrane with mechanical reinforcement and chemical stabilizers. Despite an increasing number of recent studies demonstrating its improved lifetime in accelerated stress testing (AST), its structure and transport properties have not been investigated in a systematic fashion. In this paper, we report water uptake, dimensional change, conductivity, and mechanical properties of Nafion XL membrane, as well as its strong anisotropy, in comparison to (unreinforced) Nafion 212 membrane. Moreover, water-domain spacing and crystallinity of Nafion XL membrane, determined from small- and wide-angle X-ray scattering (SAXS/WAXS) experiments, are correlated with the measured properties to establish a structure/property relationship, and discussed within the context of composite materials. It is also found that (pre)conditioning of the membrane by heating in water at different temperatures could have significant impacts on its structure/property relationship, in particular, the mechanical stability and conductivity, and their anisotropy, which were related to morphological changes observed from microscopy studies. The findings reported here not only provide a new dataset that can be used for PEFC performance and durability modeling but also benefit the efforts on developing composite ion-conductive membranes. [ABSTRACT FROM AUTHOR]

This article presents the technical characteristics of a newly built small- and wide-angle X-ray scattering (SAXS/WAXS) apparatus dedicated to structural characterization of a wide range of nanomaterials in the powder or dispersion form. The instrument is based on a high-flux rotating anode generator with a molybdenum target, enabling the assessment of highly absorbing samples containing heavy elements. The SAXS part is composed of a collimation system including a multilayer optic and scatterless slits, a motorized sample holder, a vacuum chamber, and a two-dimensional image-plate detector. All the control command is done through a TANGO interface. Normalization and data correction yield scattering patterns at the absolute scale automatically with a q range from 0.03 to 3.2 Å−1. The WAXS part features a multilayer collimating optic and a two-dimensional image-plate detector with variable sample-to-detector distances. The accessible q range is 0.4-9 Å−1, ensuring a large overlap in q range between the two instruments. A few examples of applications are also presented, namely coupled SAXS/WAXS structure and symmetry determination of gold nanocrystals in solution and characterization of imogolite nanotubes and iron-filled carbon nanotube samples. [ABSTRACT FROM AUTHOR]

SUNBIM (supramolecular and submolecular nano- and biomaterials X-ray imaging) is a suite of integrated programs which, through a user-friendly graphical user interface, are optimized to perform the following: (i) q-scale calibration and two-dimensional → one-dimensional folding on small- and wide-angle X-ray scattering (SAXS/WAXS) and grazing-incidence SAXS/WAXS (GISAXS/GIWAXS) data, also including possible eccentricity corrections for WAXS/GIWAXS data; (ii) background evaluation and subtraction, denoising, and deconvolution of the primary beam angular divergence on SAXS/GISAXS profiles; (iii) indexing of two-dimensional GISAXS frames and extraction of one-dimensional GISAXS profiles along specific cuts; (iv) scanning microscopy in absorption and SAXS contrast. The latter includes collection of transmission and SAXS data, respectively, in a mesh across a mm2 area, organization of the as-collected data into a single composite image of transmission values or two-dimensional SAXS frames, analysis of the composed data to derive the absorption map and/or the spatial distribution, and orientation of nanoscale structures over the scanned area. [ABSTRACT FROM AUTHOR]

Aiming to establish the relationship between structures of precursor film and its capability of pore formation, high density polyethylene (HDPE) precursor films are prepared under varied draw ratios and die temperatures, which are further subjected to stretching to generate microporous membranes. Structures like long period, lateral size of lamellae, orientation parameter, and fibril content of the precursor films are obtained by small/wide angle X-ray scattering (SAXS/WAXS), and morphologies of the microporous membranes are examined with scanning electron microscope. It is found that the content of fibrils and orientation parameter of lamellar stacks in the precursor films play counter effects on the capability of micropore formation. A critical window to balance the conflict is revealed with an optimal fibril content of about 6.4%, at which maximal porosity and most homogeneous porous structures are obtained. A schematic model is proposed to account for the role of the fibrils and the oriented lamellar stacks during pore formation, which may guide the production of high-performance HDPE microporous membranes. [ABSTRACT FROM AUTHOR]

Corn starches with amylose contents ranging from 0 to 80% were suspended in 60 wt% water or ethanol and subjected to high hydrostatic pressure (HHP) up to 600 MPa. The impact of HHP treatment on the granule morphology, lamellae structures, and crystalline characteristics were examined with a combination of SAXS, WAXS and optical microscopy. All starch dispersed in water showed a decrease in area of the lamellar peak in the SAXS data at q ∼ 0.6 nm −1 . The lamellae thickness ( d ) increased for pressurized waxy, normal, and Gelose80 corn starches, suggesting water is forced into starch lamellae during HHP. However, for Gelose50 corn starch, the d remained constant over the whole pressure range and light microscopy showed no obvious granule swelling. WAXS studies demonstrated that HHP partially converted A-type starches (waxy and normal corn) to starches with a faint B-type pattern while starches with a B + V-type pattern (Gelose50 and Gelose80), were not affected by HHP. All corn starches suspended in ethanol showed no detectable changes in either granule morphology, or the fractal, the lamellae, and the crystalline structures. [ABSTRACT FROM AUTHOR]

Recent molecular dynamics simulations, verified experimentally by solution-state x-ray scattering experiments, have found that κ -carrageenan chains contain helical secondary structure, akin to that found in the solid-state, even in aqueous solution. Furthermore, upon the addition of ions to single chains the simulations found no evidence that any conformational transitions take place. These findings challenge the long-held assumption that the so-called disorder-to-order transition in carrageenan systems involves a uni-molecular 'coil-to-helix transition'. Herein, the results of further molecular dynamics simulations undertaken using pairs of κ -carrageenan chains in 0.1 M NaI solutions are reported, and are validated experimentally using state-of-the-art solution-state WAXS experiments. From initially separated chains double-helices are shown to form, leading the authors to propose 'two single helices-to-stabilized double-helix' as a description of the molecular events taking place during the disorder-to-order transition. [Display omitted] [ABSTRACT FROM AUTHOR]

Crystallization behaviors of crystalline–crystalline diblock copolymers are important in understanding the structure evaluation. In this work, we investigated effects of crystallization temperature on the interactive crystallization behavior of crystalline–crystalline diblock copolymer of poly( l -lactide)- block -poly(ethylene glycol) copolymer (PLLA- b -PEG) with differential scanning calorimetry (DSC), polarized optical microscopy (POM), atomic force microscopy (AFM), small and wide angle X-ray scattering (SAXS/WAXS) and Fourier transform infrared (FTIR) spectroscopy techniques. SAXS results showed that during the two-step crystallization process PEG blocks should crystallize within spaces from interlamellar or interfibrillar of PLLA crystals, and the microstructure formation in PLLA- b -PEG copolymer was greatly dependent on T C,PLLA (crystallization temperature of PLLA). Moreover, crystal nucleation and crystallization rate of PEG blocks were also dependent on T c,PLLA . On the other hand, almost reversible crystalline structure changes of PLLA crystals was induced by crystallization and melting of PEG blocks. And the extent of crystalline structure change of PLLA blocks by PEG crystallization was increased with T c,PLLA increasing. [ABSTRACT FROM AUTHOR]

The solution state structure of κ -carrageenan is typically described as a 'random coil', to indicate a lack of defined secondary structure elements. From this starting point the assignment of an optical-rotation-detected change that follows the introduction of particular ions to such solutions as a 'coil-to-helix transition' seems unambiguous, and thus the canonical description of this important biopolymer's gelling behaviour was born. However, the notion that κ -carrageenan exists in solution as a random coil, devoid of secondary structure, has been questioned a number of times previously in the literature, particularly by the molecular modelling and NMR communities. Regrettably, there has been little desire to-date to address these largely overlooked studies or consider their implications for the nature of the so-called 'coil-to-helix transition'. Despite evidence to the contrary, the random-coil-paradigm has prevailed. Here, new data from synchrotron-enabled solution-state x-ray scattering experiments, combined with state-of-the-art atomistic molecular dynamics simulations, are used to show that the solution-state structure of κ -carrageenan in fact retains many of the helical motifs present in the solid-state, as inferred from fibre diffraction data. Furthermore, no evidence is found to suggest that single chains undergo any uni-molecular conformational transition upon the addition of ions. These findings once again challenge the paradigm that κ -carrageenan exists as a 'random coil' in the solution state, and thereby question the long held assumption that a uni-molecular 'coil-to-helix transition' precedes the dimerization of helices. [Display omitted] [ABSTRACT FROM AUTHOR]

ABSTRACT A mesiodens is the most common type of supernumerary tooth present in conjunction to normal dentition. A mesiodens may commonly occur in the central region of the upper or lower jaw. A mesiodens is different from normal teeth in terms of structure and shape. The aim of this study is to evaluate the micro- and nanoscale structural properties of mesiodens dentin by combined small- and wide-angle X-ray scattering (SAXS/WAXS) and Fourier transform infrared (FTIR) spectroscopy. Five freshly extracted, noncarious mesiodens and five normal dentin disks prepared from human incisor teeth were compared. Using FTIR, the phosphate-to-amide I, carbonate-to-phosphate, and carbonate-to-amide I band area ratios and the crystallinity index were quantified. SAXS/WAXS were used to study the nanostructure of mesiodens. An increase in the mineral content in the mesiodens dentin with respect to the normal group was found. Crystallinity was also significantly increased and the protein content decreased in the mesiodens dentin compared with that of normal dentin. SAXS/WAXS results revealed that mesiodens dentin has a more calcified tissue. Further, SAXS analysis revealed a nonuniform distribution of dentin fibrils in mesiodens. Microsc. Res. Tech., 78:52-58, 2015. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Abstract: The knowledge of the mechanical properties of dental materials related to their hierarchical structure is essential for understanding and predicting the effect of microstructural alterations on the performance of dental tissues in the context of forensic and archaeological investigation as well as laser irradiation treatment of caries. So far, few studies have focused on the nano-scale structure-mechanical function relations of human teeth altered by chemical or thermal treatment. The response of dental tissues to thermal treatment is thought to be strongly affected by the mineral crystallite size, their spatial arrangement and preferred orientation. In this study, synchrotron-based small and wide angle X-ray scattering (SAXS/WAXS) techniques were used to investigate the micro-structural alterations (mean crystalline thickness, crystal perfection and degree of alignment) of heat-affected dentine and enamel in human dental teeth. Additionally, nanoindentation mapping was applied to detect the spatial and temperature-dependent nano-mechanical properties variation. The SAXS/WAXS results revealed that the mean crystalline thickness distribution in dentine was more uniform compared with that in enamel. Although in general the mean crystalline thickness increased both in dentine and enamel as the temperature increased, the local structural variations gradually reduced. Meanwhile, the hardness and reduced modulus in enamel decreased as the temperature increased, while for dentine, the tendency reversed at high temperature. The analysis of the correlation between the ultrastructure and mechanical properties coupled with the effect of temperature demonstrates the effect of mean thickness and orientation on the local variation of mechanical property. This structural–mechanical property alteration is likely to be due to changes of HAp crystallites, thus dentine and enamel exhibit different responses at different temperatures. Our results enable an improved understanding of the mechanical properties correlation in hierarchical biological materials, and human dental tissue in particular. [Copyright &y& Elsevier]