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Controlling the magnitude of structural dynamics in flexible MOF films by an applied stimulus is largely desired for specific applications such as energy storage. Herein, by introducing chlorine substituents in an azobenzene-infiltrated Cl-DMOF-1 film structure, a significantly slowed structural response is obtained upon photo-switching of the system. [ABSTRACT FROM AUTHOR]

3D imaging provides crucial details about the objects and scenes that may not be obtained via 2D imaging methods. However, there are several applications in which the object to be 3D-imaged requires to be immobilized. The integrated digital holographic microscopy (DHM) and optical trapping (OT) system is a useful solution for such a task, but both DHM and OT are mostly suitable for microscopic specimens. Here, for the first time to the best of our knowledge and as an analogy to the DHM-OT system, we introduce integral imaging (InIm) and acoustic trapping (AT) integrated system for 3D imaging of immobilized mesoscopic and macroscopic objects. Post-processing of InIm data enables reconstructing the scene at any arbitrary plane, therefore, it re-focuses any particular depth of the object, which is a curtail task, especially when the object is trapped by AT. We demonstrate the capability of our system by simultaneous trapping and 3D imaging of single and multiple irregularly shaped objects with mm sizes. [ABSTRACT FROM AUTHOR]

Understanding and control of thermal transport in solids at the nanoscale are crucial in engineering and enhance the properties of a new generation of optoelectronic, thermoelectric and photonic devices. In this regard, semiconductor superlattice structures provide a unique platform to study phenomena associated with phonon propagations in solids such as heat conduction. Transient X‐ray diffraction can directly probe atomic motions and therefore is among the rare techniques sensitive to phonon dynamics in condensed matter. Here, optically induced transient heat conduction in GaAs/AlAs superlattice structures is studied using the EIGER2 detector. Benchmark experiments have been performed at the Austrian SAXS beamline at Elettra–Sincrotrone Trieste operated in the hybrid filling mode. This work demonstrates that drifts of experimental conditions, such as synchrotron beam fluctuations, become less essential when utilizing the EIGER2 double‐gating mode which results in a faster acquisition of high‐quality data and facilitates data analysis and data interpretation. [ABSTRACT FROM AUTHOR]

Thanks to specific physico-chemical properties, drug delivery systems based on nanoparticles have proven to effectively transport delicate molecules for therapeutic purposes, protecting them from degradation, increasing their stability in the blood circulation and allowing to convey and release the transported substances in specific areas of the body. Nanoparticles obtained from biopolymers for applications in medicine and pharmaceutics have become particularly popular in recent years due to the enormous research effort in the field of vaccines to respond to the pandemic emergency. Among the various types of biopolymers used to produce nanoparticles for therapeutics, lipids have characteristics that make them biocompatible, with low toxicity and ease of clearance. They can be synthesized by designing their characteristics according to the foreseen administration path, or to the target of the transported drug. The analytical methods mostly used to evaluate the characteristics of lipid nanosytems for drug delivery involve studying their effects on cells, in vitro and in vivo. Although it is often considered a "niche technique" for research in the bio-related sciences, Small Angle X-ray Scattering (SAXS) is a versatile tool to study the structure of nanosystems based on lipids, both ex situ and in situ. Therefore, it allows to evaluate both the effect of the different synthesis parameters and of the exposure of lipid nanoparticles to physiological conditions, which is of fundamental importance to design efficient drug delivery systems. In this mini-review, we will report some recent examples of characterization and design of nanoparticles based on lipids, where SAXS has been a fundamental step both to guide the synthesis of nanomaterials with tailored characteristics, and to understand the interaction between nanomaterials and cells. [ABSTRACT FROM AUTHOR]

Magnetic levitation (MagLev) has recently emerged as a powerful method to develop diagnostic technologies based on the exploitation of the nanoparticle (NP)–protein corona. However, experimental procedures improving the robustness, reproducibility, and accuracy of this technology are largely unexplored. To contribute to filling this gap, here, we investigated the effect of total flow rate (TFR) and flow rate ratio (FRR) on the MagLev patterns of microfluidic-generated graphene oxide (GO)–protein complexes using bulk mixing of GO and human plasma (HP) as a reference. Levitating and precipitating fractions of GO-HP samples were characterized in terms of atomic force microscopy (AFM), bicinchoninic acid assay (BCA), and one-dimensional sodium dodecyl sulfate–polyacrylamide gel electrophoresis (1D SDS-PAGE), and nanoliquid chromatography–tandem mass spectrometry (nano-LC-MS/MS). We identified combinations of TFR and FRR (e.g., TFR = 35 μL/min and FRR (GO:HP) = 9:1 or TFR = 3.5 μL/min and FRR (GO:HP) = 19:1), leading to MagLev patterns dominated by levitating and precipitating fractions with bulk-like features. Since a typical MagLev experiment for disease detection is based on a sequence of optimization, exploration, and validation steps, this implies that the optimization (e.g., searching for optimal NP:HP ratios) and exploration (e.g., searching for MagLev signatures) steps can be performed using samples generated by bulk mixing. When these steps are completed, the validation step, which involves using human specimens that are often available in limited amounts, can be made by highly reproducible microfluidic mixing without any ex novo optimization process. The relevance of developing diagnostic technologies based on MagLev of coronated nanomaterials is also discussed. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this literature review is to investigate the role of the beneficiation stage in the Life Cycle Assessment (LCA) of metals and minerals with a focus on the flotation process. Methods: The systematic literature search included LCA studies comprising the beneficiation stage in their system boundaries and resulted in 29 studies that met the criteria requirements and were analysed. First, the system boundaries are investigated, along with the level of detail in the description of the sub-processes (e.g. flotation) and data granularity. Then, the life cycle inventories are scrutinised: data transparency and the relation between system granularity and data availability is commented. Of particular relevance, the way in which the functional unit is dealt with is examined. Finally, studies impact assessments are compared and discussed, and key parameters are highlighted. Results and discussion: For system boundaries, beneficiation is generally embedded into the mining stage. Even when described on its own, important sub-processes (e.g. flotation) are not considered, except for eight cases analysed. Functional unit definition is hindered by the output of the system being an intermediate product. Indeed, most studies use a declared functional unit but fail to provide its relevant characteristics, which is essential for a correct interpretation of results and for comparisons. Most studies rely on secondary data, not always presented transparently, to describe beneficiation. Results on the role of beneficiation in the metal value chain environmental impacts are conflicting, partly because of its site dependency. Site-dependent parameters found to be determining are ore grade, energy mix, mining technique, concentrate grade and ore mineralogy. Conclusions: The flotation process, and more generally the beneficiation stage, is typically overlooked in LCA studies despite its growing relevance. Beneficiation not being assessed as a standalone stage, detailed in its subprocess, the use of outdated and secondary data, along with a lack of transparency in the inventory and in the key parameters are all factors that affect the environmental assessment of the entire metal and mineral sector, and thus the LCA of many products. Recommendation: Greater efforts should be allocated to considering the sub-processes in the beneficiation stage, particularly flotation. Information on the identified key parameters should be available to the practitioners and sensitivity analyses to investigate their influence are recommended. Hotspots specific to flotation have been identified and should be used to orient data gathering when focusing on this process. Five options of functional unit and their application are recommended. [ABSTRACT FROM AUTHOR]

An automatic sample changer system for measurements of large numbers of liquid samples – the µDrop Sample Changer – is presented. It is based on a robotic arm equipped with a pipetting mechanism, which is combined with a novel drop‐based sample holder. In this holder a drop of liquid is suspended between two parallel plates by surface tension. The absence of a transfer line benefits the cleaning, improving the background as well as making it faster and more efficient than most comparable capillary‐based systems. The µDrop Sample Changer reaches cycle times below 35 s and can process up to 480 samples in a single run. Sample handling is very reliable, with a drop misplacement chance of about 0.2%. Very low sample volumes (<20 µl) are needed and repeatable measurements were performed down to 6 µl. Using measurements of bovine serum albumin and lysozyme, the performance of the instrument and quality of the gathered data of low and high concentrations of proteins are presented. The temperature of samples can also be controlled during storage and during measurement, which is demonstrated by observing a phase transition of a mesophase‐forming lipid solution. The instrument has been developed for use in small‐angle X‐ray scattering experiments, which is a well established technique for measuring (macro‐)molecules. It is commonly used in biological studies, where often large sets of rare samples have to be measured. [ABSTRACT FROM AUTHOR]

A new setup for picosecond pump–probe X‐ray scattering at the Austrian SAXS beamline at Elettra‐Sincrotrone Trieste is presented. A high‐power/high‐repetion‐rate laser has been installed on‐site, delivering UV/VIS/IR femtosecond‐pulses in‐sync with the storage ring. Data acquisition is achieved by gating a multi‐panel detector, capable of discriminating the single X‐ray pulse in the dark‐gap of the Elettra hybrid filling mode. Specific aspects of laser‐ and detection‐synchronization, on‐line beam steering as well protocols for spatial and temporal overlap of laser and X‐ray beam are also described. The capabilities of the setup are demonstrated by studying transient heat‐transfer in an In/Al/GaAs superlattice structure and results are confirmed by theoretical calculations. [ABSTRACT FROM AUTHOR]

On road dynamic charging represents a possible solution for the electrification of the transport sector and eventually, for its decarbonisation. However, only a few studies have evaluated the environmental impact of this technology. A detailed life cycle assessment (LCA) of charging infrastructure is missing. This study is a life cycle assessment of the construction and maintenance of an electrified road (e-road) equipped with dynamic wireless power transfer technology (DWPT). The data from an e-road tested in a test site in Susa (Italy) have been adapted for motorway applications. The results show the relevance of wireless power transfer components compared to traditional components and materials. The wireless power transfer (WPT) component production in fact accounts for more than 70% of the impacts in the climate change category, even though it represents less than 1% weight. Maintenance is the phase with the highest impact due to the structural features of the e-road. However, there is considerable uncertainty about this value which still requires further refinement when more data from e-road monitoring are available. [ABSTRACT FROM AUTHOR]

Life Cycle assessments (LCAs) on electric mobility are providing a plethora of diverging results. 44 articles, published from 2008 to 2018 have been investigated in this review, in order to find the extent and the reason behind this deviation. The first hurdle can be found in the goal definition, followed by the modelling choice, as both are generally incomplete and inconsistent. These gaps influence the choices made in the Life Cycle Inventory (LCI) stage, particularly in regards to the selection of the electricity mix. A statistical regression is made with results available in the literature. It emerges that, despite the wide-ranging scopes and the numerous variables present in the assessments, the electricity mix's carbon intensity can explain 70% of the variability of the results. This encourages a shared framework to drive practitioners in the execution of the assessment and policy makers in the interpretation of the results. [ABSTRACT FROM AUTHOR]

The controlled growth of Ag nanoparticles into graphene-TiO mesoporous films has been triggered by hard X-ray exposure provided by a synchrotron storage ring. The kinetic process has been studied by UV-visible spectroscopy as a function of the X-ray dose and compared to the nanoparticle growth induced in a bare mesoporous titania matrix. The graphene layers act as a preferential nucleation sites, allowing a faster nucleation of the nanoparticles. Moreover, the growth of larger nanoparticles is also promoted as a function of the exposure dose. The combined bottom-up and top-down approach to fabricate nanocomposites porous films embedding both graphene and plasmonic nanoparticles is expected to be a fundamental tool for the design of new analytical platforms based on the enhancement of the Raman signals. Graphical Abstract: [ABSTRACT FROM AUTHOR]

Surface-enhanced Raman scattering (SERS) has already demonstrated its significant potential in analytical science. Thus, current efforts are focused on the development of affordable and reproducible SERS substrates, which exhibit high enhancement factors and uniform responses. A large number of strategies were adopted to produce effective SERS substrates; however, most of them are tuned for the use of single excitation wavelength and consequently can only be applied for a limited number of analytes. Hence, SERS substrates that demonstrate broadband plasmonic properties represent a more flexible analytical tool for multi-wavelength or tunable light sources, especially for biological applications. In the current study, we demonstrate that direct laser writing (DLW), which activates a photoreactive moiety and immobilizes functionalized gold nanoparticles on chemically modified glass substrates, can be used to produce SERS substrates of various sizes and geometries. We show that by tuning the DLW parameters a broad plasmonic response is obtained, enabling the use of these substrates for multi-wavelength SERS analysis. Two Raman reporters, a small synthetic benzotriazole azo organic dye and a larger biological molecule, hemin, are tested at three fixed excitation wavelengths in the visible range (473 nm, 532 nm and 660 nm). SERS enhancement factors show a weak dependence on the wavelength used and the molecules investigated; moreover, the possibility of creating arbitrary shaped and uniform structures is demonstrated. The reported results show that DLW is an excellent technique to engineer microstructured and broadband SERS substrates. [ABSTRACT FROM AUTHOR]

Hard X-rays, deriving from a synchrotron light source, have been used as an effective tool for processing hybrid organic-inorganic films and thick coatings up to several micrometres. These coatings could be directly modified, in terms of composition and properties, by controlled exposure to X-rays. The physico-chemical properties of the coatings, such as hardness, refractive index and fluorescence, can be properly tuned using the interaction of hard X-rays with the sol-gel hybrid films. The changes in the microstructure have been correlated especially with the modification of the optical and the mechanical properties. A relationship between the degradation rate of the organic groups and the rise of fluorescence from the hybrid material has been observed; nanoindentation analysis of the coatings as a function of the X-ray doses has shown a not linear dependence between thickness and film hardness. [ABSTRACT FROM AUTHOR]

An innovative approach towards the physico-chemical tailoring of zinc oxide thin films is reported. The films have been deposited by liquid phase using the sol-gel method and then exposed to hard X-rays, provided by a synchrotron storage ring, for lithography. The use of surfactant and chelating agents in the sol allows easy-to-pattern films made by an organic-inorganic matrix to be deposited. The exposure to hard X-rays strongly affects the nucleation and growth of crystalline ZnO, triggering the formation of two intermediate phases before obtaining a wurtzite-like structure. At the same time, X-ray lithography allows for a fast patterning of the coatings enabling microfabrication for sensing and arrays technology. [ABSTRACT FROM AUTHOR]

A current trend of applied research in the field of nanomaterials is the integration of bottom up and top down fabrication methods. Sol-gel chemistry is widely applied to obtain different functional materials from a bottom up route, especially in the case of thin films. To fabricate devices based on sol-gel films, which include nanocomposites and mesoporous ordered materials, application of lithography technologies is mandatory. Among the different lithographic approaches, photolithography is widely used by companies using micro-fabrication processes. In this context, photolithography is a typical top down method that requires to be integrated as much as possible with deposition of thin films from a liquid phase. Recently we have developed a new integrated fabrication method which uses high energy photons, such as hard X-rays, which typically have energies between 2.5 and 12 keV, for the manipulation and production of a large variety of functional materials and devices. In the present review a short overview of such achievements is presented. [ABSTRACT FROM AUTHOR]

Liquid jets are of interest, both for their industrial relevance and for scientific applications (more important, in particular for X-rays, after the advent of free-electron lasers that require liquid jets as sample carrier). Instability mechanisms have been described theoretically and by numerical simulation, but confirmed by few experimental techniques. In fact, these are mainly based on cameras, which is limited by the imaging resolution, and on light scattering, which is hindered by absorption, reflection, Mie scattering and multiple scattering due to complex air/liquid interfaces during jet break-up. In this communication it is demonstrated that synchrotron small-angle X-ray scattering (SAXS) can give quantitative information on liquid jet dynamics at the nanoscale, by detecting time-dependent morphology and break-up length. Jets ejected from circular tubes of different diameters (100-450 mm) and speeds (0.7-21 m s-1) have been explored to cover the Rayleigh and first wind-induced regimes. Various solvents (water, ethanol, 2-propanol) and their mixtures have been examined. The determination of the liquid jet behaviour becomes essential, as it provides background data in subsequent studies of chemical and biological reactions using SAXS or X-ray diffraction based on synchrotron radiation and free-electron lasers. [ABSTRACT FROM AUTHOR]

The need for a quick and radical green transition gives a key role to the financial system as the main source to fund the change. This debate also involves the development of banking regulation tools able to serve the transition. Building on previous works, we propose a method to weight banks' assets that combines conventional financial risks and environmental risks to calculate prudential capital requirements, and we apply it to the EU Taxonomy's technical screening criteria to build an environmental risk indicator based on the buildings' energy consumptions. We show how to calculate the tool endogenously for the taxonomy sections related to buildings (new construction, purchase of building, renovation), thus proving its immediate enforceability, using data from the Lombardy's housing stocks. Finally, we conduct a stress test for the Italian banking system showing that our proposal would be an effective incentive for the banks to fund the green transition of the construction sector. Disclaimer: The views expressed are those of the authors and do not involve the responsibility of the Bank of Italy or RSE. [ABSTRACT FROM AUTHOR]

The article examines the effect induced by exposure of sol-gel thin films on hard X-rays generated by synchrotron radiation. It evaluates the effects of the radiation by fourier transform infrared spectroscopy, spectroscopic ellipsometry and atomic force microscopy. It also gives a better insight into the basic chemical-physical effects of hard X-ray interaction with oxides and hybrid organic-inorganic sol-gel materials.

The Energy System lab at the University of Trieste has carried out a study to investigate the reduction in performance of high temperature polymer electrolyte membrane (HTPEM) fuel cell membrane electrode assemblies (MEAs) when subjected to different ageing tests. In this study, start and stop cycles, load cycles, open circuit voltage (OCV) permanence and constant load profile were considered. Polarization curves (PC) together with electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) data were recorded during the ageing tests to assess the fuel cell performance. In this paper, experimental data are presented to confirm the test methodology previously proposed by the authors and to quantitatively correlate the performance degradation to the operational profiles. It was demonstrated that OCV condition, start and stop and load cycling increase degradation of the MEAs with respect to constant load operation. As expected, the OCV is the operational condition that influences performance degradation the most. Finally, the MEAs were analyzed with synchrotron small angle X-ray scattering (SAXS) technique at the Austrian SAXS beamline at Elettra-Sincrotrone Trieste to analyze the nano-morphological catalyst evolution. As for the catalyst morphology evolution, the ex situ SAXS methodology proposed by the authors is confirmed in its ability to assess the catalyst nanoparticles aggregation. [ABSTRACT FROM AUTHOR]

Mesoporous materials bear great potential for biotechnological applications due to their biocompatibility and versatility. Their high surface area and pore interconnection allow the immobilization of molecules and their subsequent controlled delivery. Modifications of the mesoporous material with the addition of different chemical species, make them particularly suitable for the production of bioactive coatings. Functionalized thin films of mesoporous silica and titania can be used as scaffolds with properties as diverse as promotion of cell growth, inhibition of biofilms formation, or development of sensors based on immobilized enzymes. The possibility to pattern them increase their appeal as they can be incorporated into devices and can be tailored both with respect to architecture and functionalization. In fact, selective surface manipulation is the ground for the fabrication of advanced micro devices that combine standard micro/nanofluids with functional materials. In this review, we will present the advantages of the functionalization of silica and titania mesoporous materials deposited in thin film. Different functional groups used to modify their properties will be summarized, as well as functionalization methods and some examples of applications of modified materials, thus giving an overview of the essential role of functionalization to improve the performance of such innovative materials. [ABSTRACT FROM AUTHOR]

X-ray diffraction using micro- and nanofocused beams is well suited for nanostructure analysis at different sites of a biological micro-object. To conduct in vitro studies without mechanical contact, we developed object manipulation by optical tweezers in a microfluidic cell. Here we report x-ray microdiffraction analysis of a micro-object optically trapped in three dimensions. We revealed the nanostructure of a single starch granule at different points and investigated local radiation damage induced by repeated x-ray exposures at the same position, demonstrating high stability and full control of the granule orientation by multiple optical traps. [ABSTRACT FROM AUTHOR]