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[Display omitted] • The thermal behavior of DBN and DBU PILs with carboxylic acids of varying chain length was explored. • The effects of base, acid, and temperature on C p , m 0 of the PILs were studied. • The T g and C p , m 0 of the PILs show a significant dependence with the base. • PILs can display high values of excess heat capacities, depending on their ionicity. • Evidence for the occurrence of nanostructuration in PILs with acids of longer chain length. Herein, we report the thermal behavior and high-precision heat capacity values, at T = 298.15 K, and in the range from 283 to 363 K, for several protic ionic liquids (PILs), derived from the 1:1 liquid mixtures of the organic superbases 1,5-diazabicyclo[4.3.0]non-5-ene (DBN) and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) with some carboxylic acids (propionic, butyric, hexanoic and octanoic). Glass transition, T g , crystallization, T c , cold-crystallization, T cc , and melting, T m , temperatures were determined for the PILs studied, showing marked differences with the base – T g is lower for all DBN PILs, and no T m , T c , and T cc could be obtained for the DBU PILs. The standard molar heat capacities, C p , m 0 , were obtained with an uncertainty of less than ±0.3 % and their dependence on the base and on the acid's chain length was studied in detail. The C p , m 0 of the DBU PILs were found to be significantly higher than those of the corresponding DBN PILs, which corroborates the greater ionic character of DBU PILs. The heat capacity data suggested the existence of a trend-shift with the chain length of the carboxylic acid. Similar to aprotic ionic liquids, the shift occurs around n = 5 (pentanoic acid) and suggests the existence of some degree of nanostructuration into polar and non-polar domains in PILs with larger acids. Moreover, PILs can display abnormally high excess heat capacities, resulting from the formation of an ionic mixture from neutral species. Analysis of the calculated excess heat capacities indicates that PILs tend to become less ionic as the temperature increases, which goes in accordance with the acid-base equilibrium shift. [ABSTRACT FROM AUTHOR]

The prompt management of patients with massive burns is essential to maximize survival by preventing infection, hemorrhage, fluid and heat loss, and to optimally prepare the wound bed for the application of autografts or cultured tissue-engineered artificial autologous skin. Acute treatments are typically based on temporary bio-dressings, commonly cadaveric skin allografts, but supply challenges, high costs and increasingly stringent regulatory requirements preclude their widespread use. Nanostructured fibrin-agarose hydrogels (NFAH) have been proven to be safe and effective biomaterials in preclinical and clinical studies, and show good hemostatic and biomechanical properties. Here we generated and tested NFAH with embedded allogeneic dermal fibroblasts (NFAH-F) under Good Manufacturing Practice (GMP) conditions. Fibroblasts were first expanded and characterized to create a GMP bank and the NFAH-F was manufactured on demand. Three patients with major burns were treated with this product as a temporary bio-dressing under compassionate use. Our results suggest that NFAH-F product was a safe product and no adverse reactions were observed. In all cases, the patients survived until definitive treatment. Therefore, the application of NFAH-F might be a temporary bio-dressing for patients with massive burns when cadaveric skin allografts are not available. [Display omitted] • Fibroblasts were efficiently expanded and banked under GMP compliant conditions. • A bio-dressing based on nanostructured fibrin-agarose hydrogels with embedded allogeneic fibroblasts (NFAH-F) was designed. • Three massively burned patients were treated with NFAH-F under compassionate use and no adverse reactions were observed. • The application of NFAH-F might be a temporary bio-dressing for patients when cadaveric skin allografts are not available. [ABSTRACT FROM AUTHOR]

Abstract Low-density nanocellular polymers are required to take advantage of the full potential of these materials as high efficient thermal insulators. However, their production is still a challenging task. One promising approach is the use of nanostructured polymer blends of poly(methyl methacrylate) (PMMA) and a block copolymer poly(methyl methacrylate)-poly(butyl acrylate)-poly(methyl methacrylate) (MAM), which are useful for promoting nucleation but seem to present a severe drawback, as apparently avoid low relative densities. In this work, new strategies to overcome this limitation and produce low-density nanocellular materials based on these blends are investigated. First, the effect of very low amounts of the MAM copolymer is analysed. It is detected that nanostructuration can be prevented using low copolymer contents, but nucleation is still enhanced as a result of the copolymer molecules with high CO 2 affinity dispersed in the matrix, so nanocellular polymers are obtained using very low percentages of the copolymer. Second, the influence of the foaming temperature is studied. Results show that for systems in which there is not a clear nanostructuration, cells can grow more freely and smaller relative densities can be achieved. For these studies, blends of PMMA with MAM with copolymer contents from 10 wt% and as low as 0.1 wt% are used. For the first time, the production strategies proposed in this work have allowed obtaining low density (relative density 0.23) nanocellular polymers based on PMMA/MAM blends. Graphical abstract Image 1 Highlights • Low-density nanocellular polymers based on PMMA/MAM blends are produced. • Low MAM copolymer contents, as low as 0.1 wt%, are used to produce such materials. • The physical mechanisms that allow this reduction of the density are discussed. [ABSTRACT FROM AUTHOR]

Abstract The development of new high performance materials faces the challenge of implementing low temperature densification processes to overcome current technological limitations. In this context, the hydrothermal sintering, inspired by the natural processes of geological and biological mineralization, has recently emerged as a major opportunity to develop new and/or optimized materials that respond to today's scientific, technological and related socio-economic issues. The purpose of this viewpoint paper is to present opinions and propose future outlook for hydrothermal sintering based on the most recent achievements. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Abstract Raman spectra of soot particles were monitored in the gaseous flow extracted from the burning regions of two low-pressure premixed ethylene flames, for the first time. The flame conditions were chosen to explore the diversity of soot nanostructure in slightly sooting flames. Evaluation of the Raman spectral parameters revealed that the soot particles exhibited a strongly disordered structure and a large proportion of sp hybridization of the carbon. The appearance of sp carbon chains composing up to 30% of the total carbon content as well as an olefinic component may indicate their important role in soot nucleation and growth in low pressure ethylene flames. Hence, Raman spectroscopy of soot particles in the aerosol phase revealed that accretion and cyclization of the aliphatic carbon including sp carbon chains could thus be of importance for the initial soot growth and require more investigation. [ABSTRACT FROM AUTHOR]

Abstract Nanostructured polymer blends with CO2-philic domains can be used to produce nanocellular materials with controlled nucleation. It is well known that this nanostructuration can be induced by the addition of a block copolymer poly(methyl methacrylate)-poly(butyl acrylate)-poly(methyl methacrylate) (MAM) to a poly(methyl methacrylate) (PMMA) matrix. However, the effect of the block copolymer molecular weight on the production of nanocellular materials is still unknown. In this work, this effect is analysed by using three types of MAM triblock copolymers with different molecular weights, and a fixed blend ratio of 90 wt% PMMA and 10 wt% of MAM. Blends were produced by extrusion. As a result of the extrusion process, a non-equilibrium nanostructuration takes place in the blends, and the micelle density increases as MAM molecular weight increases. Micelle formation is proposed to occur as result of two mechanisms: dispersion, controlled by the extrusion parameters and the relative viscosities of the polymers, and self-assembly of MAM molecules in the dispersed domains. On the other hand, in the nanocellular materials produced with these blends, cell size decreases from 200 to 120 nm as MAM molecular weight increases. Cell growth is suggested to be controlled by the intermicelle distance and limited by the cell wall thickness. Furthermore, a theoretical explanation of the mechanisms underlying the limited expansion of PMMA/MAM systems is proposed and discussed. Graphical abstract Image 1 Highlights • Nanocellular polymers based on PMMA/MAM blends are produced. • Nanostructuration of the blends depends on MAM molecular weight. • Then, MAM molecular weight can used as a tool to control the cellular structure. [ABSTRACT FROM AUTHOR]

The influence of the synthesis and sintering methods on the structural, microstructural, stoichiometry and thus the magnetocaloric properties of the La 0.7 Ca 0.3 MnO 3 compound has been thoroughly studied. Soft-chemistry (sol-gel and polyol) synthesis and spark plasma sintering (SPS) procedures, used to obtain nanostructured materials, were compared to the traditional ceramic ones. This work evidences that SPS treatment not only reduces the grain size but also leads to oxygen sub-stoichiometry. This entails a lower Mn 4+ content in the manganite, and probably heterogeneity in the Mn 4+ grain distribution, which have consequences on the magnetic and magnetocaloric properties: a lower maximum entropy variation which is compensated by a larger transition temperature range. The sample prepared by combining polyol soft-chemistry synthesis and SPS sintering displays a higher maximum relative cooling power value, equal to 70% of that of gadolinium, the most effective material for domestic magnetic refrigeration. [ABSTRACT FROM AUTHOR]

The Surface Enhanced Raman Scattering (SERS) has demonstrated its high efficiency to increase the Raman signal of chemical and biological species and to be able to observe and identify a very low quantity of molecules paving the way to the single molecule sensitivity. Its application to molecular detection is now intensively developed to set-up various kind of highly sensitive sensors. In this paper, we propose a review on the SERS technique and on its use as sensor for the detection of explosives, since it is of first importance in the framework of public safety. After a description of the SERS principle, we report on the different methods developed for such detection (substrates, detection principles…) and on the results obtained (targeted analytes, sensitivity, limit of detection…). We discuss all these results and compared them with other current analytical methods. [ABSTRACT FROM AUTHOR]

The Surface Enhanced Raman Scattering (SERS) is a powerful method to observe and detect a large panel of molecules. Through the highly enhanced Raman signal, it is possible to identify a very low concentration of molecules and to improve the limit of detection in sensor applications. In this paper, we propose a review on the use of SERS as sensor for the detection of food contaminants. We describe the different approaches and methods proposed in the literature for such detection as well as the main sensing characteristics provided by the use of this technique. All these results will be discussed and compared with other detection methods. [ABSTRACT FROM AUTHOR]

Here we report the optimization on the covalent grafting methodology of a tripod-shaped penta( p -phenylene), 1 , on alkynyl-terminated silicon surfaces, and the incorporation of an active theophylline derivative, 2 , for the specific immobilization of proteins. The tripodal molecule presents azide-terminal groups to be attached onto a silicon surface containing an alkynyl monolayer. Initially, compound 1 has been covalently incorporated on alkynyl-terminated Si wafers, by the copper catalyzed alkyne-azide 1,3-dipolar cycloaddition (CuAAC, a click reaction). The tripod density on the silicon surface is tuned by performing the CuAAC reaction at different concentrations of 1 , as well as under different experimental conditions (T, base, copper source, shaking). Then, tripod 1 -modified surface has also been biofunctionalized with 2 . The effective preparation of this silicon-modified surface allowed us to study the streptavidin immobilization on the surface. Characterization of the different surfaces has been carried out by X-ray Photoelectron Spectroscopy (XPS), Atomic Force Microscopy (AFM) and Bright-Field Optical Transmission Microscopy (Confocal) techniques. We also include density functional theory (DFT) analysis of the organic structures to confirm the height-profile and the tripod-surface relative configuration extracted from AFM images. [ABSTRACT FROM AUTHOR]

Abstract We report here the successful design of 0–3 type nanocomposites where 30 nm ferromagnetic metallically conducting cores of manganite La 0.66 Sr 0.34 MnO 3 (LSMO) are discretely distributed in an insulating silica matrix. Starting from LSMO@SiO 2 core@shell nanoparticles, hydrothermal sintering process was used as a low temperature densification route (300 °C, 350 MPa, 90 min) in presence of 0.2 M aqueous sodium hydroxide solution. This process based on a pressure solution creep in the contact zones between nanoparticles allows the design of complex microstructures preventing the grain growth of the cores and the formation of interphases between the cores and the matrix. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

The heat capacity and thermal behavior trend along the 1-alkyl-3-methylimidazolium hexafluorophosphate [C n C 1 im][PF 6 ] (with n = 2–10, 12) ionic liquids series, is used to explore the effect of the alkyl chain length in the nanostructuration. The heat capacities of the studied ILs were measured with an uncertainty better than ± 0.15% and are in excellent agreement with the available data in the literature. An odd-even effect for the specific and volumic heat capacities of the [C n C 1 im][PF 6 ] series was found. The observed odd-even effect in the liquid heat capacity was rationalized considering the preferential orientation of the terminal CH 3 group. The higher specific/volumic heat capacities shown for the [C 6 C 1 im][PF 6 ] and [C 8 C 1 im][PF 6 ] are an indication of an additional conformational disorder increase in the liquid phase that could be related with a weaker alkyl chain interdigitation capability of the even number chain ILs. The melting temperatures and consequent ∆ s l H m o and ∆ s l S m o trend along the alkyl series present a V-shape profile that is explained based on the analysis of the balance between the initial decrease of the electrostatic interaction potential and the increase of the van der Waals interactions with the increasing size of the alkyl side chain of the cation. The inhibition of crystallization for intermediate alkyl chain size (from [C 5 C 1 im][PF 6 ] to [C 8 C 1 im][PF 6 ]) seems to arise from the overlapping of the hypothetical cold crystallization temperature by the melting temperature. Above the critical alkyl size, CAS, a regular increase in the entropy and enthalpy profiles presents a similar shape than the observed in other alkane series and is a strong support of the intensification of the ILs nanostructuration. [ABSTRACT FROM AUTHOR]

A triblock copolymer (BCP) of the PS- b -PB- b -PS (SBS) type [PS: polystyrene, PB: polybutadiene] with cylindrical morphology containing pristine or PS-functionalised multi-walled carbon nanotubes (MWCNTs) was exposed to steady shear and large amplitude oscillatory shear (LAOS). Axis symmetric shear was applied in a rheometer for the orientation of the BCP cylinders and the alignment of MWCNTs within the BCP matrix. Neat SBS and SBS nanocomposites with 0.1 wt% of pristine MWCNTs ( p -CNT) and PS-grafted MWCNTs (PS-g-CNT) were prepared by solution mixing prior to the shear experiments. Small angle X-ray scattering (SAXS) and transmission electron microscopy (TEM) indicated long-range ordered BCP cylindrical nanodomains highly oriented and hexagonally packed in the case of LAOS. SBS/CNT-g-PS nanocomposite showed slightly disturbed BCP orientation, however well aligned CNTs in the direction of shear for LAOS conditions. The extent of ordering with respect to the different shear conditions and MWCNT surface functionalisation are elucidated. [ABSTRACT FROM AUTHOR]

In this work, the properties of cellulose (CE)/xyloglucan (XG) biopolymer blends are investigated, taking inspiration from the outstanding mechanical properties of plant cell walls. CE and XG were first co-solubilized in an ionic liquid, 1-ethyl-3-methylimidazolium acetate, in order to blend these biopolymers with a varying CE:XG ratio. The biopolymers were then regenerated together using water to produce solid blends in the form of films. Water-soluble XG persisted in the films following regeneration in water, indicating an attractive interaction between the CE and XG. The final CE:XG ratio of the blends was close to the initial value in solutions, further suggesting that intimate mixing takes place between CE and XG. The resulting CE/XG films were found to be free of ionic liquid, transparent and with no evidence of phase separation at the micron scale. The mechanical properties of the blend with a CE:XG ratio close to one revealed a synergistic effect for which a maximum in the elongation and stress at break was observed in combination with a high elastic modulus. Atomic force microscopy indicates a co-continuous nanostructure for this composition. It is proposed that the non-monotonous variation of the mechanical performance of the films with XG content is due to this observed nanostructuration. [ABSTRACT FROM AUTHOR]

Pure tysonite La 0.95 Ba 0.05 F 2.95 is nanostructured by using the ball-milling technique. Size and pollution rate are minimized using the statistical method of Design of Experiment. The nanocrystalline powders are studied by X-ray and TEM analyses and by 19 F solid state NMR and impedance spectroscopies. Specific surface area and F/OH substitution rate are estimated by BET measurements and thermal analysis (TGA-MS), respectively. Fluorine environments and mobilities are discussed on the basis of 19 F solid state NMR data, both prior and after thermal treatment. The ionic conductivity, evaluated from sintered pellets, is compared at different thermal treatment temperatures. Thermal treatment tends to reduce microstrains up to 500 °C and to increase the grain size above this temperature. Optimal conductivity is obtained for a thermal treatment from 700 °C and no significant improvement of the conductivity by nanostructuration is observed. [ABSTRACT FROM AUTHOR]

• CTA is partially miscible with VG or with PEO block in binary blends. • Morphology of binary blends strongly depends on both VG or EPE content. • Established morphologies diagram confirm that VG acted as nanostructuration agent. • The same morphologies is achieved adding VG and less EPE block copolymer. Polymer blends based on cellulose triacetate (CTA) modified with poly(ethylene oxide-b-propylene oxide-b-ethylene oxide) triblock copolymer (PEO-PPO-PEO or EPE) and 1,1′‑diethyl-4,4′-bipyridinium dibromide (viologen or VG) were employed to obtain nanostructured micrometric films. 3VG/CTA binary blend showed worm-like structure, which was disrupted by the addition of 5 wt% of VG as a consequence of higher partial miscibility between blend components of 3VG/CTA blend. The competition between the self-assembly ability of EPE triblock copolymer and the formation of CTA crystalline lamellae was responsible for the morphology of EPE/CTA binary blends. In the ternary blends, CTA matrix was partially miscible with both VG and PEO block of EPE triblock copolymer. AFM proved that the addition of the 3 and 5 wt% of VG into had a similar effect on the final morphology of ternary systems contained 5 and 10 wt% of EPE triblock copolymer. The obtained results confirm not only self-organization ability of EPE block copolymer but also of VG. In ternary blends, VG acted as nanostructuration agent leading to similar morphology using less content of EPE block copolymer. The results provided from this investigation work allowed to build the morphologies diagram to design CTA based blends with tuneable morphologies obtained playing with VG and EPE content. [ABSTRACT FROM AUTHOR]

In this work, we produce bulk nanostructured Mg 2 Si 0.4 Sn 0.6 thermoelectric materials made of nanograins with sizes below 200 nm and containing a fine distribution of Sn-rich nanoparticles. These materials are obtained by the mechanical alloying followed by spark plasma sintering. The microstructure and transport properties, and their evolutions upon aging, are investigated. A model is developed to capture the different contributions to the phonon scattering processes arising from the nano/microstructural parameters. The calculations show quantitative agreement with the temperature and the temporal dependence of the lattice thermal conductivity of the nanostructured Mg 2 Si 0.4 Sn 0.6 alloy. This work provides a general analytic approach for identifying the individual contributions of the microstructural parameters on the thermal conductivity which is a very important property controlling the performance of thermoelectric materials. [ABSTRACT FROM AUTHOR]

We report the design of a polyoxometalate-nanostructured immunosensor for benzo[a]pyrene (B[a]P) detection. The organic–inorganic hybrid polyoxometalate (POM) (NBu 4 ) 3 [PW 11 O 39 {(SiC 6 H 4 NH 2 ) 2 O}] carrying two amine functions was covalently attached to a functionalized gold substrate to achieve a nanometric organization of amine groups at its surface. Pyrenebutyric acid (PBA) was subsequently grafted to amine groups to create the sensing layer. The detection of B[a]P in the indirect competitive format was carried out using a monoclonal anti-B[a]P antibody whose binding to the immunoprobe was monitored with a quartz crystal microbalance with dissipation measurement (QCM-D). The performances of the POM-nanostructured biosensor were compared to a reference sensor constructed from a cysteamine self-assembled monolayer. QCM-D measurements displayed significant input from POM-nanostructuration. Both the accessibility of the analogue on the surface and the analytical performances were enhanced showing a promising effect of this strategy of nanostructuration for the biosensing of small molecules. [ABSTRACT FROM AUTHOR]

The low vapor pressure of explosives makes the gaseous detection challenging and drives even the particle detection. There is a need to provide easy portable systems, highly spreadable. A bio-inspired concept was developed to detect explosive vapors with unprecedent sensitivities. Vertically aligned TiO2 nanotubes were grown on a cantilever. The sensors successfully detected trinitrotoluene (TNT) and pentaerythritol tetranitrate (PETN) with a minimum threshold concentration down to 0.8 ppt. This work describes also the investigations undertaken to develop the characterization of explosives by nanocalorimetry, which is able to identify explosives in form of single particles. [ABSTRACT FROM AUTHOR]

[Display omitted] • Innovative nanostructurated device for thiol analysis. • The device was easy to use and allowed low molecular thiols quantification. • Thiols were quantified in simple and biological matrices. • Reduced glutathione concentration was successfully evaluated in rat plasma. Thiols are very important molecules in the biomedical field involved for example in redox homeostasis. Their detection and quantification remain difficult due to their poor stability (oxidation) linked to their strong reactivity towards other thiols (by the formation of S-S bonds) or other interfering molecules in the medium. Cellulose membranes with immobilized gold nanoparticles (AuNP) were developed to capture and quantify thiols in simple and complex matrices. This device was first optimized and characterized in terms of nanostructuration and thiol adsorption. N -Acetylcysteine (NAC) and reduced glutathione (GSH), chosen as model molecules, were filtered through the device demonstrating a maximal adsorption capacity of 270 and 60 nmol respectively. In a second step, the adsorbed species were subjected to ligand exchange using a more reactive thiol, dithiothreitol. The results showed release rates of approximately 90% for NAC and GSH. Finally, the amount of endogenous GSH in rat plasma was determined without any pretreatment. For the first time to our knowledge, a nanostructured device for the capture, selective and sensitive quantification of thiols is proposed. This device is easy to handle and overcomes matrix effects. Moreover, the very large concentration factor induced by this technology will be a valuable asset to decrease the quantification limits of analytical methods. [ABSTRACT FROM AUTHOR]

Various ruthenium dioxide nanostructures were grown locally by the oxidation of ruthenium samples with an Ar-O 2 microwave micro-afterglow operated at atmospheric pressure. A special attention was paid to the distribution of the surface temperature of the sample which evolves between 530 K and 820 K. Whatever the treatment time, the temperature and the gas composition set within the studied ranges, a general nanostructure, made of lamellae separated by 20–50 nm, is found. When the temperature rises, localized nano-sea urchins, nanotubes with square sections, nano-needles, and more complex structures are found spread over the surface. Treated surfaces were characterized by different surface diagnostics (SEM, XRD, SIMS, etc.) Finally, a growth mechanism is proposed emphasizing the role of emerging defects and stress on the appearance of localized nanostructures. [ABSTRACT FROM AUTHOR]

Highlights: [•] Permanent superhydrophobic properties on injection-molded polypropylene substrates can be obtained by a simple dip-nanocoating process. [•] At Ti–OH surface relative concentrations higher than about 25%, the surface kept a superhydrophobic static state but lost its self-cleaning properties. [•] Precise tuning on the superhydrophobic dynamic component can be obtained by the control of the roughness together with the chemical surface composition of polar groups. [ABSTRACT FROM AUTHOR]

Abstract: Biofuel cells, and among them enzymatic biofuel cells, are expected to take part in a sustainable economy in a next future. The development of such biodevices requires significant improvements in terms of efficiency of enzyme immobilization at the electrodes, so as to enable direct electron transfer, and to increase and stabilize the current densities. Many works during the last years aimed at reaching higher current densities, thus power densities, while increasing the long term stability of the enzymatic bioelectrodes. Search for new enzymes, wild type or mutants, new entrapment procedures, but also new electrode architectures, have been targeted. This review focuses on the materials developed and involved during the last few years to meet these demands via nanostructuration of electrode interfaces. Discussion is essentially focused on cases where direct electron transfer between enzymes and electrochemical interfaces are involved. After having introduced the main reasons for the need of nanostructuration, the materials and methods that are newly developed are described. The consequences on improved performances for enzymatic bioelectrodes are discussed, and finally major challenges for future research are addressed. [Copyright &y& Elsevier]

Abstract: In this paper we report the synthesis and characterization of a new fluorescent ligand, ACRI-1 and its Co(II) coordination complex 1, [Co2(ACRI-1)2]. Complex 1 has been characterized by X-ray crystallography, magnetism and paramagnetic proton NMR. Nanostructuration of complex 1 has been achieved as monodisperse fluorescent nanoparticles and as thin layers on a HOPG surface. The thin layers have been characterized by AFM and GIXRD. [Copyright &y& Elsevier]

Abstract: Densities, viscosities and refractive index, as a function of temperature, and isobaric thermal expansion coefficient, were determined for 1-alkyl-3-methylimidazolium hexafluorophosphate, [CN−1C1im][PF6] (where N=5 to 10) series of ionic liquids. The density presents a regular decrease along the ionic liquid series, with no detectable alkyl chain length dependence of the thermal expansion coefficient. Both the refractive index and viscosity show a trend shift along the series around the [C6C1im][PF6] that could be associated to the impact of the change in the nanostructuration of the ionic liquids. The experimental results are compared with the analogous [CN−1C1im][NTf2] series and the effect of the anion is analyzed. The sphericity of the [PF6]− anion is reflected in the lower pre-exponential VTF parameter, Aη , and the higher viscosity of the [CN−1C1im][PF6], when compared with the [CN−1C1im][NTf2] series, is ruled by the higher energy barriers, which are related with stronger electrostatic interaction due to the low charge dispersion of the [PF6]−.anion. [Copyright &y& Elsevier]

Highlights: [•] Shear alignment of a block copolymer/epoxy thermosetting system is achieved. [•] Pre-shearing conditions play a key role in the orientation of the system. [•] Long-range order is investigated by TEM and SAXS. [ABSTRACT FROM AUTHOR]

Highlights: [•] A nanostructured polypyrrole powder is synthesized via a redox core–shell mechanism. [•] For that, a nanostructured MnO2 powder is used as oxidizing sacrificial template. [•] Reaction product is a pure and conducting PPy powder with a large specific area. [•] Its stoichiometry and production of soluble Mn2+ cations are clearly evidenced. [•] These new data will strengthen control in the synthesis of MnO2/PPy composite materials. [Copyright &y& Elsevier]

Abstract: Recently, Ni3.5Sn4 intermetallic has been reported as an efficient buffering material for Si-containing composite negative electrodes used in Li-ion batteries. In the present work, the electrochemical properties of this Ni-overstoichiometric compound are studied in detail. Micrometric, nanosized and carbon-added nanosized Ni3.5Sn4 have been investigated. For all materials, very good cycle life is obtained over more than 400 cycles. Nanosized Ni3.5Sn4 with crystallite size of 6nm exhibits a reversible capacity of 240mAhg−1, ten times higher than for the micrometric state. Moreover, nanosized Ni3.5Sn4 exhibits high-rate capability with 80% of full discharge capacity at 16C. Carbon addition slows down kinetics but increases the reversible capacity up to 273mAhg−1. The electrochemical properties of nanostructured Ni3.5Sn4 phase make it a promising constituent for composite anodes of Li-ion batteries. [Copyright &y& Elsevier]

Abstract: Thanks to excellent mechanical and biochemical properties, the nickel–titanium shape memory alloy (Nitinol) constitutes an increasingly praised platform material in dental, cardiovascular and orthopedic biomedical devices. In order to strengthen their protective abilities toward corrosion, to reinforce their biocompatibility and to confer them specific osseointegrative capacities, Nitinol plates are covered with a thin tantalum layer by electrodeposition in the 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ionic liquid. XPS and SEM/EDX analyses highlight the chemical and morphological characteristics of the deposits: notably, these present an intrinsic dimpled nanometric structuration which is particularly remarkable considering the “soft” experimental conditions and very interesting for fundamental and applied bioactive perspectives. The present study investigates the specific and synergic effects of the Ni occurrence on the surface of the Nitinol substrates, the presence of fluorine species in the working bath, and the electrodeposition duration on the resulting formation process, morphology and chemical composition of the tantalum coating. Finally, samples are submitted to electrochemical characterizations and in vitro hydroxyapatite growth tests for a primary assessment of their corrosion resistance and osseoinductive features. [Copyright &y& Elsevier]

Abstract: We report on the combination of nanosphere lithography, electrodeposition and click chemistry to produce nanostructured surfaces with improved number of anchored molecules. Our strategy was developed here for the immobilization of ferrocene at glassy carbon electrode, both used as models. The nanostructuration of the surface was obtained by adsorption of 900nm-diameter polystyrene nanosphere followed either by electropolymerization of N-(10-azidodecyl)pyrrole or by electrografting of 4-azidobenzenediazonium. In the case of poly-N-(10-azidodecyl)pyrrole, the AFM analysis of the surface after electropolymerization and removal of the nanospheres show the formation of a patterned film with holes separated of ≈900nm. In the case of 4-azidobenzenediazonium, the electrografting proceeds similarly to bare surfaces, but with a decrease of reduction peak intensity due to the partial coverage of the electrode surface with insulating nanospheres. For both modified surfaces, the immobilization of ferrocene by copper(I) catalyzed azide-alkyne cycloaddition was clearly evidenced by cyclic voltammetry. The evaluation of the surface coverage shows that the nanostructuration leads to larger specific area for the chemical anchorage of ferrocene. Finally this procedure produces versatile functionalization of conductive materials used in various applications. [Copyright &y& Elsevier]

Abstract: High pressure torsion (HPT) tests can be used to transform the structure of materials. Several studies in the literature highlight that such tests are a means of investigating certain formation mechanisms of Tribological Transformed Structures (TTS) outside contacts, as they reproduce conditions that are close to those found inside them (quasi-hydrostatic pressures and shearing) under conditions that are easier to control than in a real contact. As there is no unique path leading to deformation with TTS in real contacts, it has been decided to simplify the history of deformation as the first step in investigating the occurrence of TTS. In this study, a Bridgman anvil apparatus, which allows shearing samples in torsion under pressure, is used to test ultra high purity iron (99.99999%) with an initial grain size of 100μm, under a mean pressure of 0.5GPa. The microstructural investigations led to establishing a map identifying the refined zones within the volume of the sample and linked to contact conditions. This work considers these zones with the finest microstructure (size grains of about 220nm) as “TTS”. The experimental study is coupled with finite element analysis to investigate the specificity of the stress and strain cycles of the microstructure produced. Although further work is needed to validate the suggested comparison to friction induced transformed layers, the results showed that “TTS” are produced in a specific sample volume linked to sliding/adhesion contact conditions. The coupling between experiments and modeling shows that “TTS” formation can be associated with high hydrostatic stress components, high local plastic strains and high strain gradients. [Copyright &y& Elsevier]

Abstract: Self-organized block copolymers can be effectively utilized as nanostructured precursors to functionalized ordered mesoporous polymeric materials. Novel nanoporous polystyrene frameworks with carboxylic acid (COOH)-coated pore walls were obtained from the selective degradation of the polyester block in polystyrene-block-poly(d,l-lactide) (PS-b-PLA) diblock copolymers. By resorting to an asymmetric difunctional initiator, an orthogonal atom transfer radical polymerization (ATRP)/ring-opening polymerization (ROP) tandem approach enabled the synthesis of such diblock copolymers with a carboxyl group at the junction point between both blocks. Upon the shear flow induced by a channel die processing, highly oriented copolymers were afforded as evidenced by small-angle X-ray scattering (SAXS). Under mild alkaline conditions, the quantitative hydrolysis of the PLA nanodomains yielded ordered mesoporous materials containing nanoscopic channels lined with chemically accessible and modifiable COOH functional groups. The PS-b-PLA precursors were carefully analyzed by size exclusion chromatography (SEC) and 1H NMR, while the resulting porous frameworks were investigated by scanning electron microscopy (SEM) and nitrogen sorption porosimetry. [ABSTRACT FROM AUTHOR]

Abstract: In this work, a new method to prepare fluorinated coatings with mechanical properties enhanced has been developed. Pyridinium, imidazolium, and phosphonium ionic liquids have been synthesized and used as new synthetic building blocks in a polytetrafluoroethylene matrix. The strategy demonstrated using long alkyl chain cations provides an opportunity to prepare nanomaterials with a nanoscale structuration. The design of these new ionic and nanostructured materials is very dependent on the cation–anion combination of ILs. The morphology analyzed by transmission electronic microscopy (TEM) shows that it is clearly tuned by the chemical nature of ILs. The finest structuration leads to a dramatic compromise between stiffness and deformation of material. The small-angle X-Ray scattering (SAXS) shows the evolution of the ionic networks during the mechanical sollicitation. [Copyright &y& Elsevier]

Abstract: A modified Metropolis atomistic simulation is proposed to model the structure of grain boundaries (GBs) and interfaces in ionic nanostructured systems and is applied to the magnetically interesting case of iron trifluoride (FeF3). We chose long-range interatomic potentials adjusted on experimental results and adapted a previously established Monte Carlo scheme consisting of various modifications of the simulated annealing/Metropolis algorithm. Atomic structures of twisted and tilted GBs as a function of the relative disorientation of the grains have been achieved yielding close to experimentally measured properties. This approach takes into account the structure of the grains far from the interface in order to constrain the relative orientation of the grains, without any periodic boundary conditions. One concludes that a long-range Coulombic fall off of the interatomic potentials is necessary to obtain GB structures presenting a correct local topology but with a smooth transition from crystalline to amorphous states. The structural features are finally discussed in terms of topological aspects and local magnetic structure. [Copyright &y& Elsevier]

Abstract: Poly[Styrene-b-Butadiene-b-(Methyl Methacrylate)], SBM triblock copolymers have been incorporated in different polyurethane, PU formulations in order to prepare nanostructured materials. Macrodiols used for PU synthesis were based on a central bis-phenol A, BPA unit with two hydroxyl-terminated oligo(oxypropylene), BPA-POx or oligo(oxyethylene), BPA-EO chains with varying lengths. The initial solubility of the three blocks and the rheological behavior of the solutions in macrodiols and also in two diisocyanates, isophorone diisocyanate, IPDI, and 1,3-xylylene diisocyanate, XDI have been first characterized. The PMMA block is the most soluble and its role during the reaction is to stabilize the initial nanostructure or to control the reaction-induced microphase separation. Block copolymers can be dissolved first in the macrodiol, or preferably in the diisocyanate. With BPA-POx and low SBM content (<10wt%), transparent linear or crosslinked PU with well dispersed triblock nanoparticles have been prepared, depending on the molar mass of the macrodiol and on the concentration of diblock SB impurities present in the triblock. For high SBM concentrations (>50wt%), a twin screw extruder had to be used for the blending. Under well-defined conditions, transparent linear PUs and linear segmented polyurethane-ureas have been prepared. This study confirms that for designing a nanostructured material from a reactive mixture with a triblock additive, one block, called “the nanostructuring block” has to remain soluble up to the end of the reaction. [Copyright &y& Elsevier]

Abstract: Two innovative strategies for the growth of artificial pinning centers by using chemical methods are presented. First one consists of the controlled generation of artificial nanostructured templates by using diluted metalorganic solutions. We show the role of the different growth parameters as well as lattice mismatch in the final template (either BaZrO3 nanodots on SrTiO3 or CeO2 nanodots on LaAlO3). Second approach is the growth of secondary phase oxide nanoparticles (BaZrO3 and Y2O3) inside the YBCO matrix grown by the trifluoroacetates route. The relevance of lattice mismatch is also investigated in this case. We show that both strategies lead to a significant improvement of vortex pinning properties of the YBCO films suggesting that artificial pinning centers has been effectively generated. These results prove that chemical methods are a promising technique for the nanostructuration of coated conductors. [Copyright &y& Elsevier]

Abstract: We have nanostructured CoPt alloy layers prepared by molecular beam epitaxy, deposited directly on a MgO(001) substrate. The initial layer had the L10 tetragonal structure, ordered in the growth direction with an easy magnetization direction perpendicular to the layer plane. We realized by electron beam lithography and ion etching a network of dots spaced of 1μm and lateral sizes of 1μm, 500nm and 300nm, respectively. Whereas the continuous layers had a labyrinthine magnetic structure after perpendicular demagnetization, all the dots are monodomains with randomly distributed up and down magnetization. This is due to the fact that during the demagnetization the magnetic field is no longer sufficient to reach the nucleation field. Indeed, a single-dot hysteresis loop measured by field-dependent magnetic force microscopy shows a weak nucleation field distribution. However, the 3D micromagnetic calculations show a multidomain state for these dot sizes. This magnetic structure is similar to that observed on patterned samples, heated a short time (60s) above the Curie temperature. [Copyright &y& Elsevier]

The effect of irradiation doses and the role of grain size for titanium subjected to swift heavy 167 MeV Xe26+ ion irradiation have been investigated. Positron annihilation spectroscopy was applied for these studies. The nanostructured surface was obtained by blasting and annealing treatment. It was noticed that the concentration of vacancy clusters in the ion projectile range significantly decreased by a factor two after the grain size reduction. These clusters were built from 5 to 16 vacancies and were present mostly near the area occupied by the implanted atoms. Promising Ti properties as self-healing metal have been found. This study shows that grains structure strongly affects the resistivity of metals for irradiation and proves that surface mechanical treatments can be used as a grain size refinement method and modification of surface for enhanced irradiation resistivity. • Implementation of surface mechanical treatments for fundamental irradiation studies. • Enhanced irradiation resistivity of Ti surface by blasting. • Self-healing properties of nanostructured Ti. [ABSTRACT FROM AUTHOR]

• Spin crossover nanocrystalline Fe(pz)Pt(CN) 4 thin films fabricated by matrix assisted laser evaporation. • Preserved crystallinity of the 150 nm thick films is confirmed by diffraction study. • Laser induced desorption decreases the transition cooperativity and temperature. Thin film structures with controlled functionalities are critical to exploit the exceptional application capacity of spin crossover complexes. Here, we report spin crossover (SCO) in thin films of [Fe(pyrazine)Pt(CN) 4 ] nanocrystalline particles (NPs) deposited on monocrystalline Si by laser-mediated evaporation of a cryogenically frozen suspension of the title compound. Both X-ray diffraction and microscopic imaging of the films (thickness ~ 120 nm) confirm resembled structure of pristine nanocrystals. However, their spin crossover behavior is dramatically altered going from the cooperative and sharp transition within temperature hysteresis (16 K) around the room temperature region for reference NPs to a gradual transition type shifted downwards to 170 K for the thin films. The decrease in cooperativity within the film is due to side effect of laser-induced desorption that results in rearrangement of the pyrazine-pillared 3D framework into stacked 2D Fe[Pt(CN) 4 ] sheets in the laser affected NP regions. The observed effects have significant implications for future study on the cooperative spin transition in laser-engineered nanocrystalline films. [ABSTRACT FROM AUTHOR]

In this paper, we address the optimization of the electrical and thermoelectrical properties of nanostructured polysilicon material for integration in thermoelectric (TE) devices. In particular, we describe an original method to build a superficial and nanostructured porous polysilicon (POpSi) thin film on a Silicon substrate. This latter is electrically isolated from the conductive Silicon substrate by an SiO 2 interlayer for Van der Pauw electric and home-made thermoelectric measurements. From the characterization data, we demonstrate that the nanostructuration brought by porosification of polysilicon layers (polySi) breaks their thermal conductivity by a factor of about 30 and has no detrimental impact on their Seebeck coefficient: a POpSi with up to 62% porosity has an experimental Seebeck value of 260 µV/K when the standard polysilicon, it is built from, is n type with a carrier density of 3.4 × 1019/cm3. On the other hand, the benefit of the thermal conductivity reduction clearly over-compensates the degradation of the experimental electrical conductivity measured in the POpSi layers: in terms of the figure of merit ZT, a 25-fold increase in a POpSi layer with 44% porosity is seen compared to the standard polySi layer (it increases from 0.004 to 0.1). Such a novel material is a viable candidate for planar thermoelectric devices using Silicon technologies. In this effort, we discuss the integration of a POpSi thin film with optimum porosity into a planar TE microgenerator (µTEG) with suspended membranes supported by a simulated conversion efficiency increased by 28% compared to a µTEG integrating the standard polySi layer counterpart. ga1 • Original method to fabricate a novel nanostructured TE material : n-type porous polysilicon thin film; we name it POpSi. • Porosification of polysilicon greatly breaks its thermal conductivity with no detrimental impact on its Seebeck coefficient. • A 25-fold increase of ZT is found for POpSi with 44% porosity : ZT increases from 0.004 for standard polySi to 0.1 in POpSi. • PopSi will be a new candidate for integration into membrane-based μTEGs. • Even higher improvement expected starting the porosification process onto p-type highly B doped polySi layers. [ABSTRACT FROM AUTHOR]

Abstract: Structural and electrical properties of self-organized zirconia nanotube layers can be tuned by a simple thermal treatment. The effect of F on the electrical conductivity of the MOx nanotubes grown by anodization in fluoride-containing electrolytes is demonstrated. [Copyright &y& Elsevier]

Coherent 3D parts of cermets, made of spinel ferrite and metallic copper, are prepared in a nitrogen atmosphere by powder bed additive manufacturing of a mixture of oxide and metallic powders. The cermets obtained are constituted by the association of blocks of about 500 μm, which create between them, a relatively large porosity (# 35%). Each block is subdivided into intimately nested zones that are either predominantly metallic or predominantly oxide type. In the metal parts, a dispersion of oxide crystals is observed, whose size varies from ten nanometers to a few micrometers. A similar distribution of metal particles in the oxide zones is also demonstrated. The chemical compositions of metallic and oxide phases are slightly different from those in the initial powders. Due to the high energy density of the laser, the melting temperature of the metal and oxides could be reached and therefore this could explain the chemical composition variations in the phases and the shape of oxide and metallic nanometric grains. The process used can therefore be described as powder bed fusion. These nanostructured cermets have been used as "inert" anodes for the electrolysis of aluminum in molten cryolite. Although penalized by a high porosity, 5 mm in diameter anodes allowed to carry out an electrolysis for 4 h. Since Spark Plasma Sintering can greatly reduce their porosity, while retaining their specific microstructure, the implementation of additive manufacturing for producing "inert" anodes is therefore of real interest. [ABSTRACT FROM AUTHOR]

• Nanocellular polymers are produced using two nucleating agents. • The nucleation phenomenon occurring in each nucleating agent is investigated. • Highly anisotropic nanocellular structures are obtained with the two additives. • Cell sizes of 100–300 nm and anisotropy ratios as high as 2.77 are achieved. One strategy to produce nanocellular polymers is the use of nucleating species to promote nucleation. Whereas two-phase systems are widely studied, tri-phasic blends with two nucleating agents are uncommonly investigated. In this work, nanocellular polymers are obtained using tri-phasic blends of polymethylmethacrylate (PMMA) with two nucleating agents: needle-like sepiolites and a polymethylmethacrylate-polybutylacrylate-polymethylmethacrylate (MAM) block copolymer. Blends of PMMA with different concentrations of MAM and a fixed amount of sepiolites are produced by extrusion. Results show that at low MAM contents (1 wt%), the nucleation is a combination of the action of the two additives, but the addition of sepiolites induces the appearance of anisotropic structures. Meanwhile, at high MAM concentrations (10 wt%), MAM nanostructuration controls the nucleation and sepiolites increase the anisotropy. The alignment of the MAM micelles and the sepiolites in the extrusion direction promotes coalescence in this direction, leading to highly anisotropic nanocellular structures. Mean cell sizes of 100–300 nm and an average anisotropy ratio of 2.77 are obtained thanks to the combined effect of MAM and sepiolites. [ABSTRACT FROM AUTHOR]

• Continuously flown through microcapillary setup for high pressures. • High degree of freedom compared to conventional high pressure vessels. • Evaluation of the centroid of water's Raman stretching vibration. • Detection of nanostructuration in transparent single phase ternary mixtures. We present a fast optical screening method for the detection of sub-micro-structures nanostructuration in water-containing fluids. The optical method is based on Raman spectroscopy of the water stretching vibration. The shape of this Raman band reveals information about the development of hydrogen bonds, from which it can be extracted whether the water molecules are homogeneously distributed in the mixture, or they are heterogeneously distributed (sub-micro-structuration). The fast screening is enabled by analyzing the potentially structured ternary system CO 2 /acetonitrile/water between 10 and 22 MPa and at 308 K, 318 K and 328 K in continuously spilled microcapillary system (MCS). Compared to batch systems we specify the advantages of the MCS in which the operational conditions with respect to pressure, temperature and composition can be changed fast, reproducibly and across a wide range. [ABSTRACT FROM AUTHOR]