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This document is a summary of a special issue on inorganic materials published in the "Inorganics Materials" section. The issue covers various topics related to sustainable synthesis, surface modifications, structural properties and reactivity, environmental remediation and catalysis, composites, energy, and the use of nanomaterials against COVID-19. Each contribution focuses on a specific aspect within these areas, providing insights and advancements in the field of inorganic materials. The aim of the special issue is to increase knowledge and inspire further research in this field. The document also includes acknowledgments from the editors of the journal. [Extracted from the article]

Inorganic nanostructured (metal) oxides are a large class of inorganic materials extensively investigated for their unique and outstanding properties that allow for their use within a multitude of technological fields of emerging interest, such as (photo)catalysis, environmental remediation processes, energy storage, controlled transport and/or release of drugs and chemicals, biomedicine, sensing, development of smart materials, stimuli-responsive materials, and nanocomposites [[1], [3], [5]]. Iridium oxide is a very peculiar (metal) oxide as it is characterized by showing metallic-type conductivity and also displaying a low surface work function (which is the energy required for moving an electron from the Fermi level to the local vacuum level), high chemical stability, and good stability under the influence of high electric fields. Experimental results showed that: (i) the optimum adsorption pH for all systems is pH 2-4, (ii) the Freundlich isotherm model fitted the experimental data (mainly physisorption), (iii) the maximum adsorption capacity at optimized conditions was registered by zirconium oxide (73 mg/g), followed by cerium oxide and titania. The commercial (metal) oxides investigated were: silica, titania, zirconium oxide, cerium oxide, tin oxide, and mixed systems, such as an aluminosilicate, cerium aluminum oxide, aluminum titanium oxide, and cerium zirconium oxide. [Extracted from the article]

The occurrence of uncontrolled electrostatic discharge (ESD) is among the major causes of damage in unprotected electronic components during industrial processes. To counteract this undesired phenomenon, ESD composites showing static-dissipative and antistatic responses are developed. In particular, static-dissipative materials are able to slow down the flow of electric charges, whereas antistatic materials directly suppress the initial charges induced by undesired charging by properly dispersing conductive fillers within an insulant matrix and thus forming a conductive filler network. In this context, the purpose of this review is to provide a useful resume of the main fundamentals of the technology necessary for facing electrostatic charging. The formation mechanisms of electrostatic charges at the material surface were described, providing a classification of ESD composites and useful characterization methods. Furthermore, we reported a deep analysis of the role of conductive fillers in the formation of filler networks to allow electric charge movements, along with an overview of the different classes of inorganic conductive fillers exploitable in ESD composites, evidencing pros/cons and criticalities of each category of inorganic fillers. [ABSTRACT FROM AUTHOR]

• This paper investigates the relation between democracy and income per capita over the period 1870–2010. • I use both cross-sectional and panel fixed effects regressions to explore how this relation changed over time. • Results show that democracy positively affects income per capita in the period post-1950, especially after 1990. • Yet, democracy has no significant effect in the period prior to 1950. • In the years before World War II, income per capita is mostly explained by prior income levels and education. Economists and political scientists have long investigated the effect of political institutions on economic development, mainly focusing on cross-sectional analyses for the years after World War II. This paper takes a historical perspective and studies whether this effect can be traced back to 1870 and how it changed over time. Using both cross-sectional and panel fixed effects regressions, I show that democracy positively affects income per capita in the post-1950 period. The effect increases as time passes and becomes especially larger after 1990, i.e. with the great democratization wave induced by the Fall of the Iron Curtain. Yet, I find no effect for the period before 1950, when the variation in income per capita is mostly explained by prior income levels, and in particular, by education. These findings are robust to accounting for income dynamics as well as to using different data sources to measure political institutions. [ABSTRACT FROM AUTHOR]

Magnetically driven nanosponges with potential application as targeted drug delivery systems were prepared via the addition of magnetite nanoparticles to the synthesis of cyclodextrin and maltodextrin polymers crosslinked with 1,1′-carbonyldiimidazole. The magnetic nanoparticles were obtained separately via a coprecipitation mechanism involving inorganic iron salts in an alkaline environment. Four composite nanosponges were prepared by varying the content of magnetic nanoparticles (5 wt% and 10 wt%) in the cyclodextrin- and maltodextrin-based polymer matrix. The magnetic nanosponges were then characterised by FTIR, TGA, XRD, FESEM, and HRTEM analysis. The magnetic properties of the nanosponges were investigated via magnetisation curves collected at RT. Finally, the magnetic nanosponges were loaded with doxorubicin and tested as a drug delivery system. The nanosponges exhibited a loading capacity of approximately 3 wt%. Doxorubicin was released by the loaded nanosponges with sustained kinetics over a prolonged period of time. [ABSTRACT FROM AUTHOR]

In recent years, a great interest has arisen around the integration of naturally occurring clays into a plethora of advanced technological applications, quite far from the typical fabrication of traditional ceramics. This "second (technological) life" of clays into fields of emerging interest is mainly due to clays' peculiar properties, in particular their ability to exchange (capture) ions, their layered structure, surface area and reactivity, and their biocompatibility. Since the maximization of clay performances/exploitations passes through the comprehension of the mechanisms involved, this review aims at providing a useful text that analyzes the main goals reached by clays in different fields coupled with the analysis of the structure-property correlations. After providing an introduction mainly focused on the economic analysis of clays global trading, clays are classified basing on their structural/chemical composition. The main relevant physicochemical properties are discussed (particular attention has been dedicated to the influence of interlayer composition on clay properties). Lastly, a deep analysis of the main relevant nonconventional applications of clays is presented. Several case studies describing the use of clays in biomedicine, environmental remediation, membrane technology, additive manufacturing, and sol-gel processes are presented, and results critically discussed. [ABSTRACT FROM AUTHOR]

This study evaluates the effectiveness of using different plasma treatments to favor the compatibility between rubber and a cement matrix in composites, thus leading to a different surface reactivity of the rubber component. Plasma‐treated rubbers were introduced into two different types of concrete. Mechanical tests highlighted that Portland concrete composites filled with N2/H2 plasma‐treated rubber had increased flexural strength, toughness, and compression strength compared to composites containing untreated rubber. A scaling law is also proposed to qualitatively discriminate between related effects due to topological/roughness or intrinsic/chemical adhesion modifications. Plasma treatment can improve both intrinsic adhesion and roughness of the rubber–cement interface and thus the overall concrete strength and toughness. [ABSTRACT FROM AUTHOR]

Cu-substituted Ni ferrite systems are produced following a hydrothermal synthetic route carried out at relatively mild conditions (i.e., below 200 °C). Different degrees of substitution were investigated, ranging from bare Ni ferrite to a complete Cu-substituted system (by replacing 100% of Ni with Cu). Morphological and structural characterisations point out that the introduction of Cu in the Ni ferrite (below 50% substitution) causes a gradual reduction of the average diameter of the ferrite polyhedral nanoparticles maintaining the Ni ferrite structure. At higher content of Cu, instead, the morphology evolves toward the co-presence of iron oxides (magnetite and hematite) and copper oxide (tenorite), without the formation of bare Cu ferrite. The partially substituted Ni ferrite nanomaterials exhibit a mostly superparamagnetic behaviour in all samples, registering a reduction of the values of magnetisation saturation by increasing the Cu content. Transmission Mössbauer spectroscopy performed on these nanomaterials evidenced a gradual lowering of the Fe fraction occupying the octahedral sites and a consequent increment of the Fe fraction in the tetrahedral sites. Quantitative analysis confirms the gradual reduction of the Ni content within the ferrite samples, coupled with the opposite increment of the Cu content, whereas the Fe content is lower in the case of Ni75-Cu25 sample. This particular behaviour can be associated with the influence of Cu substitution in the Ni ferrite structure, with preferential replacement of Fe from the octahedral B-sites toward the tetrahedral A-sites. [Display omitted] • Cu-Ni ferrite systems are produced following a hydrothermal synthetic route at mild condition varying the substitution degree. • Cu-substitution causes a reduction of the average diameter of the nanoparticles, still maintaining the Ni ferrite structure. • Cu-Ni ferrite are mostly superparamagnetic, with a reduction of the magnetisation saturation by increasing the Cu content. • TMS evidenced a variation of the Fe fraction occupying both tetrahedral and octahedral sites varying the Cu-substitution. [ABSTRACT FROM AUTHOR]

Zirconium oxide is one of the most promising ceramic materials as it finds applications in several high-level technological fields, ranging from biomedicine to sensing. Zirconium oxide is characterized by showing very uncommon properties for being a ceramic substrate, such as a certain plastic behavior once subjected to mechanical stress, a naturally occurring phase transformation toughening, as well as a dramatic sensibility toward water-induced aging (if hydrothermally treated). In general, all these properties are strictly correlated with the tetragonal-to-monoclinic interphase transformation and, consequently, driven by the stabilization of the tetragonal phase. Hence, in this study, a summary of the main relevant principles guiding zirconium oxide interphase transformations is proposed, highlighting the important role of stabilizers and the correlation between microstructure and doping. A particular emphasis has been dedicated to the thermodynamics behind these phenomena. [ABSTRACT FROM AUTHOR]

Biowaste‐derived substances isolated from green compost (BBS‐GC) are environmentally friendly reactants similar to humic substances, which contain multiple functionalities, that are suitable for adsorbing different kinds of pollutants in wastewater. Herein, sodium alginate (derived from brown algae) cross‐linked with both Ca2+ ions and BBS‐GC in the form of hydrogels and dried films are proposed as green, easy‐to‐form, and handleable materials for tertiary water treatments. The results show that both hydrogels and films are mechanically stable and can effectively remove differently charged dyes through an adsorption mechanism that can be described by the Freundlich model. BBS‐GC‐containing gels always performed better than samples prepared without BBS‐GC, revealing that such unconventional materials can integrate waste valorization and water decontamination, potentially providing social and environmental benefits. [ABSTRACT FROM AUTHOR]

N-rich biochars were obtained via pyrolysis treatment of chitosan (a low-cost biopolymer from natural biomasses) at mild conditions (in the 284 °C–540 °C range), thus offering an energy efficient and low carbon footprint synthesis. These low surface area N-doped biochars were morphologically and physicochemically characterized, and tested as hosting material in lithium-sulfur (Li-S) batteries. Sulfur/biochars cathodes thus obtained showed good capacity retention and improved Coulombic efficiency compared to a standard N-rich high surface area carbon and multiwalled carbon nanotubes (MWCNT) reference substrates. Such enhanced electrochemical properties are attributable to the better retention of Li polysulfides by means of the residual functionalities still present in the biochars, thus making the valorization of chitosan potentially appealing even in the industrial sector related to the development of energy storage devices. • Chitosan has been converted into N-rich biochars via pyrolysis at mild conditions. • N-doped biochars were tested as host structure in lithium-sulfur (Li-S) batteries. • S/biochar cathodes showed improved capacity retention and Coulombic efficiency. [ABSTRACT FROM AUTHOR]

Magnetic chitosan composite (MCC) made by chitosan matrix embedding magnetite/maghemite were developed for the removal of toxic Cu(II), Pb(II), and Ni(II) from water. Thermogravimetric (TGA) and Zeta potential analyses showed that MCC contains ca. 50 wt % of chitosan and presents a value of isoelectric point (pHIEP) around 8-8.5. The magnetization curve revealed a saturation magnetization of 12 emu g−1, which indicates that MCC can be easily recovered by magnetic separation. Adsorption of the heavy metals to MCC reached equilibrium within 120 min with maximum uptakes of 108.9 mg g−1, 216.8 mg g−1 and 220.9 mg g−1 for Ni(II), Cu(II) and Pb(II), respectively. The results show that the amino and hydroxyl functional groups of chitosan are involved in the adsorption process. The reported adsorption capacity from organic pollutants, such as hydrocarbons, along with the high adsorption capacity shown for heavy metals, point out MCC being a promising versatile adsorbent for wastewater treatments. [ABSTRACT FROM AUTHOR]

This work reports the demineralisation of soluble biorganic hyrolysates (SBOs) obtained from three materials sampled from a municipal biowaste treatment plant. The SBOs contain mineral and organic matter. They are promising bio‐based multipurpose products due to their properties as biosurfactants, chemicals for the manufacture of plastics, and fertilizers for plant growth. Demineralisation of SBOs was carried out by HCl ion exchange and HF washing to assess its effect on the pristine product chemical composition and properties. The demineralized products (SBOs‐DM) were characterized by elemental analysis, potentiometric titration, 13C‐NMR spectroscopy and surface tension measurements. They were compared with pristine SBOs. The following results were obtained: ash content 0.2‐1.1% in SBOs‐DM vs. 15–28% in pristine SBOs; lower aliphatic/aromatic C ratio in SBOs‐DM (0.8‐2.0) than in pristine SBOs (1.3‐3.4); higher critical (mineral free) micellar concentration for SBOs‐DM (1‐2.7 g L−1) than for pristine SBOs (1‐2.3 g L−1). The potential applications of SBOs‐DM and pristine SBOs are discussed. [ABSTRACT FROM AUTHOR]

• Lignin-derived bio-based substances (BBS) isolated from composted urban biowastes were used as carbon source. • Nano zero-valent iron (nZVI) was obtained from carbothermal reduction at 800 °C of BBS-coated magnetite NPs. • Nanomaterials with a 77% of α-Fe over the total iron and saturation magnetization of 170 emu g−1 were obtained. Nano zero-valent iron (nZVI) has been used as an effective catalyst in different reduction reactions. In this work, a synthesis procedure to obtain a carbon based materials with high nZVI content is reported. This synthesis method consists in a carbothermal reduction at 800 °C of Fe 3 O 4 nanoparticles coated with lignin-derived bio-based substances (BBS) as carbon source, which have been previously prepared from the co-precipitation method. The obtained materials were characterized by powder X-ray diffraction (XRD), Mössbauer spectroscopy, thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and magnetization measurements. The concentration of carbon used in the synthesis process was a critical parameter for obtaining high nZVI yield. Nanomaterials with a 77% of α-Fe over the total iron and saturation magnetization (Ms) of 170 emu g−1 were obtained for the best condition. [ABSTRACT FROM AUTHOR]

Particularly‐shaped silver nanostructures are successfully applied in many scientific fields, such as nanotechnology, catalysis, (nano)engineering, optoelectronics, and sensing. In recent years, the production of shape‐controlled silver‐based nanostructures and the knowledge around this topic has grown significantly. Hence, on the basis of the most recent results reported in the literature, a critical analysis around the driving forces behind the synthesis of such nanostructures are proposed herein, pointing out the important role of surface‐regulating agents in driving crystalline growth by favoring (or opposing) development along specific directions. Additionally, growth mechanisms of the different morphologies considered here are discussed in depth, and critical points highlighted.Box of tricks: The performance of nanomaterials is strictly correlated to their size and morphology; thus, great effort has been devoted to obtaining particularly shaped nanoscopic geometries. The main relevant strategies concerning the growth of particularly shaped metallic nanostructures (and the role of surface‐regulating agents) are discussed in depth. Particular emphasis is devoted to the growth mechanisms involved for silver‐based nanostructures. [ABSTRACT FROM AUTHOR]

In this study, cellulose fibers were chemically functionalized under mild conditions by introducing palmitate groups in order to produce a hydrophobic cellulose-based ester. The effectiveness and the degree of functionalization were evaluated by FTIR spectroscopy and thermogravimetric analysis, whereas the structural integrity was confirmed by XRD measurements. The prepared materials were tested in water remediation processes from fatty oils mixtures from both animal (cod liver oil) and vegetable (sunflower oil) sources. Experimental kinetic measurements, rationalized by means of the most common models, show that the best performances were reached toward the sunflower oil, hence proving the promising application of such green materials as a sustainable alternative tool for oil-water remediation processes. [ABSTRACT FROM AUTHOR]

The present study reports on the development of a new binary filler system for rubber composites, SiO2@Al2O3, where Al2O3 sheets are grown onto SiO2 nanoparticles aggregates by a sustainable water‐based soft‐chemistry approach. The aim is to synergistically integrate the intrinsic thermal conductivity properties of Al2O3 with the peculiar reinforcement ability of SiO2 in an easy one‐pot solution, which has been exploited to prepare polybutadiene (PB) model composites by a simple solvent casting technique. More in detail, the binary filler was used as‐prepared or suitably surface functionalized with 3‐(Trimethoxysilyl)propylmethacrylate (TMSPM). The filler compatibilization and interplay with the polymeric matrix have been inspected by solid state NMR in conjunction with scanning electron microscopy. These investigations highlighted that the presence of alumina in the binary filler does not undermine the capability of silica in generating polymer chains stiffening and indicated a significant effect of the silanization in providing better filler networking and interaction with the PB host ensuring, in principle, an enhanced thermal transport. Accordingly, thermal conductivity measurements revealed that SiO2@Al2O3 introduction in PB induces a remarkable upgrade of the heat transfer, which becomes much more relevant upon surface modification with TMSPM. These results appear encouraging, paving the possibility of applying SiO2@Al2O3 model system to more complex case studies, where both improved thermal conductivity and enhanced reinforcement are required, such as tires tread formulations. Highlights: A new SiO2@Al2O3 binary filler system was proposed following a soft‐chemistry approach.The binary filler was functionalized to enhance its compatibilization.Fillers were dispersed in polybutadiene by a simple solvent casting technique.Thermal conductivity measurements revealed a remarkable upgrade of the heat transfer ability. [ABSTRACT FROM AUTHOR]

Composted urban biowaste-derived substances (BBS-GC) are used as carbon sources for the preparation of carbon-coated magnet-sensitive nanoparticles obtained via co-precipitation method and the subsequent thermal treatment at 550 °C under nitrogen atmosphere. A multitechnique approach has been applied to investigate the morphology, magnetic properties, phase composition, thermal stability of the obtained magnet-sensitive materials. In particular, pyrolysis-induced modifications affecting the BBS-GC/carbon shell were highlighted. The adsorption capacity of such bio-derivative magnetic materials for the removal of hydrophobic contaminants such as polycyclic aromatic hydrocarbons was evaluated in order to verify their potential application in wastewater remediation process. The promising results suggest their use as a new generation of magnet-responsive easily-recoverable adsorbents for water purification treatments. [ABSTRACT FROM AUTHOR]

In this study, chitosan and bio-based substances (BBS) obtained from composted biowaste were used as stabilizers for the synthesis of magnet-sensitive nanoparticles (NPs) via coprecipitation method. A pyrolysis treatment was carried out on both biopolymers at 550 °C, and their consequent conversion into a carbon matrix was followed by means of different physicochemical characterization techniques (mainly FTIR spectroscopy and XRD), whereas magnetic properties were evaluated by magnetization curves. The prepared materials were tested in water remediation processes from arsenic (As) species (both inorganic and organic forms). These tests, explained by means of the most common adsorption models, evidenced that the best performances were reached by both materials obtained after pyrolysis treatments, pointing out the promising application of such magnet-sensitive materials as easy-recoverable tools for water purification treatments. [ABSTRACT FROM AUTHOR]

After a brief historical classification of the main discoveries related to magnetism, magnetic materials have been rationally ordered in a simple (and hopefully clear) organization. A great effort was realized in the description of the different synthetic approaches for the preparation of magnet-sensitive materials (in particular, focusing on iron oxides). The principal useful techniques for evaluating the magnetic properties in materials (namely, MFM and magnetization hysteresis) have been presented, providing useful examples in order to understand both the potentiality and limits of these characterization methods. Finally, the application of magnet-sensitive materials in water remediation processes has been provided, highlighting both advantages and disadvantages of their use compared to conventional treatments. In this context, the action mechanism and the possible integration of this class of materials into processes involving wastewater treatments are widely discussed, keeping an eye toward the future perspectives. [ABSTRACT FROM AUTHOR]

Poly(vinyl alcohol- co -ethylene) was compounded with 2–10% post-harvest tomato (PHT) plant powder and processed by single-screw extrusion to yield composite films. Upon increasing the filler content, the values of the mechanical properties indicators were found to decrease as follows: Young's modulus from 1797 to 750 MPa, stress at yield from 36 to 15 MPa, maximal stress from 39 to 15 MPa, stress at break from 35 to 14 MPa, and strain at break from 6.6 to 4.3%. The results are discussed in comparison with other composite films containing poly(vinyl alcohol- co -ethylene) and water soluble biopolymers obtained by alkaline hydrolysis of fermented municipal biowastes, and with other commercial materials, such as starch based and low density polyethylene mulch films. Depending on the intended application, the post-harvest tomato blend films may be competitive for cost, performance and sustainability. [ABSTRACT FROM AUTHOR]

The aim of this review is to clarify the importance of surface modifications induced in biomaterials for hernia-repair application. Starting from the pioneering experiences involving proto-materials as ancient prosthesis, a historical excursus between the biomaterials used in hernioplasty was realized. Subsequently, after the revolutionary discovery of stereoregular polymerization followed by the PP application in the biomedical field performed by the surgeon F. Usher, a comparative study on different hernia-repair meshes available was realized in order to better understand all the outstanding problems and possible future developments. Furthermore, since many unsolved problems on prosthetic devices implantation are linked to phenomena occurring at the interface between the biomaterials surface and the body fluids, the importance of surface science in hernioplasty was highlighted and case studies of new surface-modified generations of prosthesis presented. The results discussed in the following evidence how the surface study are becoming increasingly important for a proper knowledge of issues related to the interaction between the living matter and the artificial prostheses. [ABSTRACT FROM AUTHOR]

Porous materials are powerful functional devices that can find applications in many fields, from nanotechnology to biomedicine, from catalysis to membrane separation. In general, porous materials can be processed in various forms, but a rising interest is growing around inorganic thin films and coatings, due to the increased number of applications based on their use. Among the different strategies proposed till now for preparing inorganic porous thin layers/coatings, a simple and versatile route consists in the combined use of sol-gel chemistry, templating, and spin-coating deposition. Therefore, in order to provide a helpful toolbox for users, an extended discussion around the physico-chemical principles behind each of these steps is here reported, also highlighting the advantages and disadvantages of each procedure, together with critical points. [ABSTRACT FROM AUTHOR]

Herein, porous photoactive nanocomposites are prepared by a simple one-pot synthesis approach using a salt and aqueous media. Within this reactive hypersaline route, the salt not only serves in the structuring of the composite but also becomes an integral active part of it. Here, the addition of sodium thiocyanate to a titania precursor guides, on the one hand, the formation of needle-shaped nanoparticles and, on the other hand, forms yellow compound isoperthiocyanic acid, which is homogeneously incorporated into the porous nanocomposite. Compared to a pure titania reference, this material reveals a 7-fold-increased photodegradation rate of Rhodamine B as a model compound. This reveals the reactive hypersaline route to be a promising and facile synthesis route toward photoactive porous materials. [ABSTRACT FROM AUTHOR]

In this study, bio-based substances (BBS) obtained from composted urban biowaste are used as stabilizers for the synthesis of magnet-sensitive nanoparticles (NPs). The BBS-stabilized NPs are characterized by means of different techniques (FTIR, XRD, SEM, BET analysis, magnetization curves). Additionally, TGA coupled on-line with FTIR and GC/MS analysis of the exhausted gas are performed in order to simultaneously identify all the degradation products and evaluate the exact composition of such BBS-stabilized materials. Moreover, Fenton-like or photo-Fenton-like experiments carried out at circumneutral pH are performed in order to evaluate the BBS-functionalized NPs photo-activity towards the degradation of caffeine (taken as model emerging pollutant). The obtained promising results encourage the use of BBS as a green alternative tool for the preparation of smart materials with enhanced magnet-sensitive properties, also suitable for applications in wastewater purification treatments. [ABSTRACT FROM AUTHOR]

• In this study, l -cysteine is proposed as reducing/capping agents for the production of Ag nanonets. • Ag nanonets showed different morphologies by varying the synthesis conditions. • Ag nanonets were deposited onto PDMS membranes and their SERS performance tested against 4-MBA as non-resonant probe. • A correlation between morphology and SERS response has been proposed. Highly-branched plasmonic nanostructures are interesting substrates to be exploited in Surface-Enhanced Raman Scattering (SERS) detection, as sources of efficient Raman "hot-spots". In this study, l -cysteine is proposed as reducing/capping agents for the production of Ag nanonets showing different morphologies by varying the synthesis conditions. Substrates are coupled to PDMS membranes and characterized by Raman spectroscopy using 4-MBA to define their SERS performance. Experimental evidences confirm that only the thinnest structures are able to guarantee significant SERS responses. [ABSTRACT FROM AUTHOR]

In order to confer adhesive properties to commercial polypropylene (PP) meshes, a surface plasma-induced deposition of poly-(acrylic acid) (PPAA) is performed. Once biomaterials were functionalized, different post-deposition treatments (i.e. water washing and/or thermal treatments) were investigated with the aim of monitoring the coating degradation (and therefore the loss of adhesion) after 3 months of aging in both humid/oxidant (air) and inert (nitrogen) atmospheres. A wide physicochemical characterization was carried out in order to evaluate the functionalization effectiveness and the adhesive coating homogeneity by means of static water drop shape analysis and several spectroscopies (namely, FTIR, UV–Visible and X-ray Photoemission Spectroscopy). The modification of the adhesion properties after post-deposition treatments as well as aging under different storage atmospheres were investigated by means of Atomic Force Microscopy (AFM) used in Force/Distance (F/D) mode. This technique confirms itself as a powerful tool for unveiling the surface adhesion capacity as well as the homogeneity of the functional coatings along the fibers. Results obtained evidenced that post-deposition treatments are mandatory in order to remove all oligomers produced during the plasma-treatment, whereas aging tests evidenced that these devices can be simply stored in presence of air for at least three months without a meaningful degradation of the original properties. [ABSTRACT FROM AUTHOR]

Photo-polymerization is a polymerization method widely exploited in many technological fields, due to its high versatility and fast reaction rates. In this study, poly(ethylene glycol) methacrylate (PEGMA) nanostructures are grown onto cellulose following a simple and promising light-driven reaction mechanism involving benzophenone (as photo-initiator) and UV-curing. The effectiveness of the surface functionalization has been determined by means of morphological and physicochemical characterizations, showing the formation of very sharp PEGMA nanometric architectures. [ABSTRACT FROM AUTHOR]

Hernia diseases are among the most common and diffuse causes of surgical interventions. Unfortunately, still nowadays there are different phenomena which can cause the hernioplasty failure, for instance post-operative prostheses displacements and proliferation of bacteria in the surgical site. In order to limit these problems, commercial polypropylene (PP) and polypropylene/Teflon (PP/PTFE) bi-material meshes were surface functionalised to confer adhesive properties (and therefore reduce undesired displacements) using polyacrylic acid synthesized by plasma polymerisation (PPAA). A broad physico-chemical and morphological characterisation was carried out and adhesion properties were investigated by means of atomic force microscopy (AFM) used in force/distance (F/D) mode. Once biomedical devices surface was functionalised by PPAA coating, metallic silver nanoparticles (AgNPs) with antimicrobial properties were synthesised and loaded onto the polymeric prostheses. The effect of the PPAA, containing carboxylic functionalities, adhesive coating towards AgNPs loading capacity was verified by means of X-ray photoelectron spectroscopy (XPS). Preliminary measurement of the Ag loaded amount and release in water were also investigated via inductively coupled plasma atomic emission spectroscopy (ICP-AES). Promising results were obtained for the functionalised biomaterials, encouraging future in vitro and in vivo tests. [ABSTRACT FROM AUTHOR]

In this study, chitosan, a commercially-available linear polysaccharide mainly used as antibacterial agent, functional coating and drug-delivery system, is investigated to enlighten both water interactions and its thermal stability by using a set of complementary advanced thermal techniques, rarely applied in polysaccharides characterizations. DSC and TGA, here coupled with FTIR and GCMS analysis of the exhausted gas, were used to reveal thermal events and identify degradation products as a function of the temperature: three main steps in chitosan (N-deacetylation degree, DD = 78%) thermal degradation were highlighted and mechanism proposed. In order to make a comparison with other analogous polymeric systems and validate the results obtained, a medical grade chitosan (DD > 93%) and a commercial chitin were investigated too. Moreover, the water adsorption capacity of chitosan (DD = 78%) was followed by using thermo-microgravimetry (TMG) and the distinction between weight losses of both physically and chemically adsorbed water molecules was achieved. The approach followed allows a complete characterization of the thermal behaviors of the chitosan and highlights the need for complementary advanced thermal techniques in the detailed characterization of complex biopolymers. [ABSTRACT FROM AUTHOR]

Highlights: [•] Thin mesoporous silica films were prepared from TEOS/PS-b-PEO micellar solutions. [•] Different arrangements of pores were obtained by varying composition and solution parameters. [•] Ordered mesopores span the whole thickness of very thin membranes. [•] Parameters affecting porosity were studied by microscopy and gas-volumetric analyses. [Copyright &y& Elsevier]

In a facile one-step approach, high surface area mesoporous silica powders are synthesized using ordinary salts for pore and morphology control during the sol-gel process. Applying tetraethyl orthosilicate (TEOS) as a reference system, the addition of high salt loads such as NaCl and ZnCl2 results in highly increased surface areas of up to 750 m2 g-1, predominantly in the mesopore range Besides the surface area, the pore volume and the pore size can be controlled by the salt amount as well as the salt nature, reaching values of 1.1 cm3 g-1 and 14 nm, respectively. Compared to standard processes, the herein presented synthesis is extremely simple: it only comprises the dissolution of TEOS and the respective salt in 1 M HCl, followed by solvent evaporation, salt removal through simple washing with water and drying. This way, no special equipment is required, no organic templates are to be employed, and the overall approach is highly efficient and sustainable. [ABSTRACT FROM AUTHOR]

Highlights: [•] Plasma treatments are able to form coatings onto polypropylene biomedical devices. [•] Three different types of plasma mixture (He, He/O2, He/O2/H2O) are investigated. [•] Both plasma phase reactive species and polypropylene surface are characterized. [•] A reaction mechanism relative to polymer surface functionalization is proposed. [•] A modulation of the polymer surface reactivity is achieved. [Copyright &y& Elsevier]

Abstract: Polypropylene (PP) fibers can be manufactured to form nets which can find application as prosthesis in hernioplasty. One of the most important problem to deal with when nets are applied in vivo consists in the reproduction of bacteria within the net fibers intersections. This occurs right after the application of the prosthesis, and causes infections, thus it is fundamental to remove bacteria in the very early stage of the nets application. This paper deals with the physico-chemical characterization of such nets, pre-treated by atmospheric pressure plasma dielectric barrier discharge apparatus (APP-DBD) and functionalized with an antibiotic drug such as chitosan. The physico-chemical characterization of sterilized nets, before and after the functionalization with chitosan, was carried out by means of scanning electron microscopy (SEM) coupled with EDS spectroscopy, FTIR spectroscopy, drop shape analysis (DSA), X-ray diffraction and thermal analyses (TGA and DSC). The aim of the work is to individuate a good strategy to characterize this kind of materials, to understand the effects of polypropylene pre-treatment on functionalization efficiency, to follow the materials ageing in order to study the effects of the surface treatment for in vivo applications. [Copyright &y& Elsevier]

Magnetically driven nanosponges with potential application as targeted drug delivery systems were prepared via the addition of magnetite nanoparticles to the synthesis of cyclodextrin and maltodextrin polymers crosslinked with 1,1′-carbonyldiimidazole. The magnetic nanoparticles were obtained separately via a coprecipitation mechanism involving inorganic iron salts in an alkaline environment. Four composite nanosponges were prepared by varying the content of magnetic nanoparticles (5 wt% and 10 wt%) in the cyclodextrin- and maltodextrin-based polymer matrix. The magnetic nanosponges were then characterised by FTIR, TGA, XRD, FESEM, and HRTEM analysis. The magnetic properties of the nanosponges were investigated via magnetisation curves collected at RT. Finally, the magnetic nanosponges were loaded with doxorubicin and tested as a drug delivery system. The nanosponges exhibited a loading capacity of approximately 3 wt%. Doxorubicin was released by the loaded nanosponges with sustained kinetics over a prolonged period of time. [ABSTRACT FROM AUTHOR]

• We study the impact of economic sanctions on employment in Iran. • We estimate the short-run effects of changes in import exposure on manufacturing employment at the industry level. • The sanctions caused an overall contraction in Iran's manufacturing employment growth rate by 16.4 percentage points. • We document significant reallocation effects in employment across industries with different degree of openness to trade. • The effects are driven by labor-intensive industries and industries that heavily rely on imported inputs. This paper investigates the effect of economic sanctions on employment. We exploit the imposition of a series of unexpected and unprecedented international economic sanctions on Iran in 2012 and estimate the short-run effects of the change in import exposure on manufacturing employment at the industry level. Our estimates indicate that the sanctions led to an overall decline in the manufacturing employment growth rate by 16.4 percentage points. However, we uncover significant asymmetric effects across industries with different ex-ante import shares. Interestingly, the effects are mostly driven by labor-intensive industries and industries that heavily depend on imported inputs. This suggests that the overall negative impact of the sanctions on employment might be largely due to the decline in productivity experienced by industries with a high propensity to import inputs from abroad. [ABSTRACT FROM AUTHOR]

Icephobic materials can prevent or reduce ice formation, e.g. by ensuring easy detachment, a desirable property for those applications where ice accumulation is critical to human safety. Herein, we develop a chitosan electrolyte hydrogel to create a bio-based surface with low ice adhesion. The chitosan electrolyte hydrogel is physically crosslinked and infused with salted water at concentrations from 4.5 to 30 g/L, including that of seawater (23 g/L). Depending on salt content in the hydrogel, we could obtain very low ice adhesion down to 140 kPa (at – 10°C). We hypothesize that the chitosan electrolyte hydrogel exploits the colligative properties of water avoiding the ice nucleation at the ice-hydrogel interface. To confirm the hypothesis, we investigate the chitosan electrolyte hydrogel structure by contact angles analysis, DSC, TGA, FTIR, XRD, and by rheometry for mechanical properties. We quantify the presence of non-freezing water, which creates a lubricating liquid water layer at the ice-hydrogel interface, affecting the ice detachment mechanism and lowering ice adhesion. In conclusion, the proposed chitosan electrolyte hydrogel presents a bio-based and cost-efficient strategy for ice detachment across various icing scenarios for systems operating in humid marine environments, such as offshore platforms and ships. [Display omitted] [ABSTRACT FROM AUTHOR]

The Lab4treat experience has been developed to demonstrate the use of magnetic materials in environmental applications. It was projected in the frame of the European project Mat4Treat, and it was tested several times in front of different audiences ranging from school students to the general public in training and/or divulgation events. The experience lends itself to discuss several aspects of actuality, physics and chemistry, which can be explained by modulating the discussion depth level, in order to meet the interests of younger or more experienced people and expand their knowledge. The topic is relevant, dealing with the recycling of urban waste and water depollution. The paper is placed within the field of water treatment for contaminant removal; therefore, a rich collection of recent (and less recent) papers dealing with magnetic materials and environmental issues is described in the Introduction section. In addition, the paper contains a detailed description of the experiment and a list of the possible topics which can be developed during the activity. The experimental approach makes the comprehension of scientific phenomena effective, and, from this perspective, the paper can be considered to be an example of interactive teaching. [ABSTRACT FROM AUTHOR]

This Special Issue, consisting of four reviews and three research articles, presents some of the recent advances and future perspectives in the field of magnetic materials and systems, which are designed to meet some of our current challenges. [ABSTRACT FROM AUTHOR]

Polyethylene terephthalate (PET) is the third most widely diffused polymer exploited in the packaging industry, monopolizing the bottles market for beverages, and covering almost the 16% of the European plastic consumption in the packaging industry. Even if PET primarily derived from fossil sources and remains not-biodegradable in the environment, novel advancements in the field pointed out the possibility of producing PET in a more sustainable way (e.g., from biomasses) or the possibility of biodegrade this polyester through the enzymatic action of specific genetically-modified/isolated bacteria/enzymes. By considering also the high recyclability of PET, and the possibility of potentially indefinitely re-use this material, one can assume that the future of PET is still to be written. Therefore, all aspects involving the industrial production (with traditional and sustainable chemical routes), intrinsic physicochemical/thermal/mechanical properties, undesired degradation phenomena, chemical/mechanical recycling processes, and processability of PET are here critically discussed. A particular emphasis has been dedicated to the role of PET in the packaging industry. The main achievements in the PET processing for food packaging are presented, analyzing advantages and disadvantages of each technology. This document aims at providing a useful instrument that collects past, present, and future of the PET: a well-consolidated material that has been able to renew itself over time. • The main features concerning the use of PET in the packaging industry were discussed. • Degradation phenomena occurring during PET life and processing were presented. • New recent discoveries concerning the "sustainability" of PET were discussed. • The PET processability to produce hollow objects for food packaging was critically discussed. [ABSTRACT FROM AUTHOR]

Since waste tires constitute a serious environmental concern, several studies are devoted to the use of finely divided recycled rubber for the production of rubberized concrete by partial substitution of the mineral aggregate fraction. The introduction of rubber into concrete presents several advantages (e.g., improvement of toughness and thermal/electrical/acoustic insulation capacities). Unfortunately, the addition of a high content of rubber into concrete causes an important loss of mechanical resistance of the final composite. In this context, several scientific studies are devoted to investigate the best technical solutions for favoring the interfacial adhesion between rubber and cement paste, but the interpretation of the literature is often misleading. To overcome this issue, the metadata extrapolated from the single scientific works were critically re-analyzed, forming reference diagrams where the variability fields of the different rubber concrete formulations (in terms of mechanical responses as a function of the rubber content) were defined and the best performances discussed. This study evidenced the twofold role of reference diagrams, able in both presenting the data in an unambiguous manner (for a successful comparison) and providing the guidelines for future works in this research field. [ABSTRACT FROM AUTHOR]

Magnetic structures have attracted a great interest due to their multiple applications, from physics to biomedicine. Several techniques are currently employed to investigate magnetic characteristics and other physicochemical properties of magnetic structures. The major objective of this review is to summarize the current knowledge on the usage, advances, advantages, and disadvantages of a large number of techniques that are currently available to characterize magnetic systems. The present review, aiming at helping in the choice of the most suitable method as appropriate, is divided into three sections dedicated to characterization techniques. Firstly, the magnetism and magnetization (hysteresis) techniques are introduced. Secondly, the visualization methods of the domain structures by means of different probes are illustrated. Lastly, the characterization of magnetic nanosystems in view of possible biomedical applications is discussed, including the exploitation of magnetism in imaging for cell tracking/visualization of pathological alterations in living systems (mainly by magnetic resonance imaging, MRI). [ABSTRACT FROM AUTHOR]

Chelators are widely used in conservation treatments to remove metal stains from marble, travertine, and limestone surfaces. In the current review the chemical aspects underlying the use of chelators for the removal of copper and iron stains from built heritage are described and clear criteria for the selection of the most efficient stain removal treatment are given. The main chelator structural features are outlined and the operating conditions for effective metal stain removal (pH, time of application, etc.) discussed, with a particular emphasis on the ability to form stable metal complexes, the high selectivity towards the metal that should be removed, and the high sustainability for the environment. Dense matrices often host chelators for higher effectiveness, and further research is required to clarify their role in the cleaning process. Then, relevant case studies of copper and iron stain removal are discussed. On these bases, the most effective chelators for copper and stain removal are indicated, providing chemists and conservation scientists with scientific support for conservation operations on stone works of art and opening the way to the synthesis of new chelators. [ABSTRACT FROM AUTHOR]

In this work, metallic silver flower-like and aerogel-like nanostructures deposited onto hydrophobic dielectric substrates (HF-treated Si and PDMS) showed interesting potentialities as solid SERS substrates aimed to high sensitive molecular detection and quantitation. In detail, the nanostructures were incubated in 4-MBA solutions at 10−2 M–10−9 M concentrations. The quantitative analysis confirmed a monotonic increase of the SERS signal intensity as a function of the 4-MBA concentration, following a Langmuir model, thus suggesting a chemisorption phenomenon. The best homogeneity and adhesion strength in liquid media of Ag nanostructures to the solid substrates were reached for the flower-like systems and the aerogel-like ones compared to traditional polyhedral nanostructures (taken as reference substrate), thus making them extremely appealing as a solution for the development of SERS-based sensors. [ABSTRACT FROM AUTHOR]

The photodegradation of an aqueous solution of diclofenac (DCF) has been attempted in the presence of hydrogen peroxide and organic/inorganic hybrid magnetic materials under simulated and real solar light. The hybrid magnetic materials have been prepared via coprecipitation synthesis starting from iron(II) and iron(III) inorganic salts in the presence of bioderived organic products (i.e., chitosan or bio-based substances isolated from commercially available composted urban biowastes) acting as stabilizers of the iron-containing phase. In addition to the as prepared hybrid materials, the corresponding materials obtained after a pyrolytic step at low temperature (550 °C) have been tested. The obtained results evidenced the capability of the materials to activate hydrogen peroxide at mild pH promoting DCF (photo) degradation. All the materials feature also as adsorbents since a decrease of DCF is observed also when working in the dark and in the absence of hydrogen peroxide. [ABSTRACT FROM AUTHOR]

The lack of robust and low-cost sorbent materials still represents a formidable technological barrier for long-term storage of (renewable) thermal energy and more generally for Adsorptive Heat Transformations—AHT. In this work, we introduce a novel approach for synthesizing cement-based composite sorbent materials. In fact, considering the number of available hygrosopic salts that can be accommodated into a cementitious matrix—whose morphological properties can be also fine-tuned—the new proposed in situ synthesis paves the way to the generation of an entire new class of possible sorbents for AHT. Here, solely focusing on magnesium sulfate in a class G cement matrix, we show preliminary morphological, mechanical and calorimetric characterization of sub-optimal material samples. Our analysis enables us to theoretically estimate one of the most important figures of merit for the considered applications, namely the energy density which was found to range within 0.088–0.2 GJ/m3 (for the best tested sample) under reasonable operating conditions for space heating applications and temperate climate. The above estimates are found to be lower than other composite materials in the literature. Nonetheless, although no special material optimization has been implemented, our samples already compare favourably with most of the known materials in terms of specific cost of stored energy. Finally, an interesting aspect is found in the ageing tests under water sorption-desorption cycling, where a negligible variation in the adsorption capability is demonstrated after over one-hundred cycles. [ABSTRACT FROM AUTHOR]

In recent years, significant efforts have been made in view of a transition from a linear to a circular economy, where the value of products, materials, resources, and waste is maintained as long as possible in the economy. The re-utilization of industrial and agricultural waste into value-added products, such as nanostructured siliceous materials, has become a challenging topic as an effective strategy in waste management and a sustainable model aimed to limit the use of landfill, conserve natural resources, and reduce the use of harmful substances. In light of these considerations, nanoporous silica has attracted attention in various applications owing to the tunable pore dimensions, high specific surface areas, tailorable structure, and facile post-functionalization. In this review, recent progress on the synthesis of siliceous materials from different types of waste is presented, analyzing the factors influencing the size and morphology of the final product, alongside different synthetic methods used to impart specific porosity. Applications in the fields of wastewater/gas treatment and catalysis are discussed, focusing on process feasibility in large-scale productions. [ABSTRACT FROM AUTHOR]

The incorporation of silica nanoparticles (Si-NPs) into the polymer matrix is a growing area of interest research to produce high-performance polymer nanocomposites (NCs) across a wide range of nanotechnology applications. This improvement is due to the Si-NPs capability to self-assembly giving rise to specific well-organized structures with both short- and long-range order across a hierarchy of spatial scales, determined by both NP-NP and NP-matrix interactions, involving a careful balance among attractive driving forces, repulsive forces, and directional forces. Respect to this, the aim of the present paper is to systematically review the use of Si-NPs in polymer NCs and on the role of NPs self-assembly in determining the final material properties. Firstly, we explored the synthesis and modification of both isotropic and anisotropic Si-NPs in relation with use in NC materials, focusing on NPs dispersion and distribution, as well as on the functionalization strategies of Si-NPs. Besides Si-NPs functionalization with conventional small organic molecules, a large section is devoted to an emerging class of functionalized Si-NPs with macromolecules, namely silica hairy NPs (Si-HNPs), able to give rise a rich variety of complex assemblies and materials with new structures and functionalities. Successively, NCs materials containing Si-NPs and Si-HNPs have been explored in terms of synthetic preparation and properties. The self-organization of Si-NPs and Si-HNPs in polymer matrices has been reported and its effect on the functional materials properties have been evaluated with a critical point of view on the results, limits, and future perspectives. Our review can be considered a tutorial work, aiming at providing useful insights to researchers in the field of nanotechnology and nanoscience, taking into consideration the fundamental role of NPs self-assembly processes in determining the functional material properties. [Display omitted] [ABSTRACT FROM AUTHOR]

The adsorption of dissolved organic carbon (DOC) on iron (Fe) (hydr)oxides represents an important stabilization mechanism for soil organic matter (OM) and contributes to soil C accumulation. However, in soils that experience periodic fluctuations in redox conditions the interaction between DOC and Fe (hydr)oxides may not only involve organic coatings on mineral surfaces, but also Fe-DOC coprecipitates that form during the oxidation of soil solutions containing important amounts of DOC and Fe 2+ . The aim of this work is to provide new insights into the mechanisms involved, and the amount and selectivity of C retained during the coprecipitation process. A series of Fe-OM associations with increasing C loading was synthesized at pH 6 by surface adsorption or coprecipitation (oxidation of ferrous iron) utilizing rice-straw derived dissolved organic matter. The kinetics of Fe 2+ oxidation and complexation, and the total and selective retention of DOC during the coprecipitation process were evaluated. Moreover, synthesized associations, as well as a field coprecipitate collected in situ from a paddy soil, were studied by X-ray diffraction, N 2 gas adsorption-desorption isotherms, electrophoretic mobility measurements and thermogravimetric analyses. Coprecipitation resulted in higher organic C contents (49–213 mg g −1 ) with respect to adsorbed systems (18–47 mg g −1 ), and favoured the inclusion of OM within highly aggregated associations having particularly low BET specific surface areas. Although coprecipitation led to a strong, selective retention of aromatic constituents, the initial complexation of Fe 2+ by aliphatic carboxylic moieties and precipitation as C-rich Fe-OM associations contributed to the total C retention, particularly at higher solution C/Fe ratios. These aliphatic complexes formed during coprecipitation may play an important, though often underestimated, role in C stabilization in soils experiencing frequent redox fluctuations and often characterized by elevated soluble Fe 2+ and DOC concentrations. [ABSTRACT FROM AUTHOR]