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The present study aims to investigate the potential of waste pyrolysis products to act as alternative binders or additives in asphalt preparation with the ultimate goals of effective resource use, recovery and recycling, conservation of non-renewable resources, reduction of production costs and achievement of a regenerative circular economy. Char and oil deriving from the pyrolysis of civil and agricultural wastes have been considered as new-concept alternative additives for asphalt preparation. Following an in-depth chemical and structural characterization, oil and char samples have been tested as additives in asphalt binder preparation. After the standard rheological characterization, to test the possible anti-ageing effect exerted by char and oil samples used as additives, the bituminous preparations were subjected to a short-term simulated ageing (RTFOT method) and the resulting mechanical properties evaluated. The results indicate that all the biochar samples were able to strength the overall chemical structure of bitumens and are therefore suitable to be used as bitumen modifier. It is noteworthy that two char samples (char from tires and char from lemon peels) exhibited also anti-ageing properties. As concerns bio-oil samples, in one case (oil from tires pyrolysis) a rejuvenating action is highlighted.

Bitumen, a vital component in road pavement construction, exhibits complex chemo-mechanical properties that necessitate thorough characterization for enhanced understanding and potential modifications. Nuclear Magnetic Resonance (NMR) spectroscopy emerges as a valuable technique for probing the structural and compositional features of bitumen. This review presents an in-depth exploration of the role of NMR spectroscopy in bitumen characterization, highlighting its diverse applications in determining bitumen content, group composition, molecular dynamics, and interaction with additives. Various NMR techniques, including free induction decay (FID), Carr–Purcell–Meilboom–Gill (CPMG), and Pulsed Field Gradient Stimulated Echo (PFGSE), are discussed in the context of their utility in bitumen analysis. Case studies, challenges, and limitations associated with NMR-based bitumen characterization are critically evaluated, offering insights into potential future research directions. Overall, this review provides a comprehensive overview of the current state-of-the-art in NMR-based bitumen characterization and identifies avenues for further advancement in the field.

Improving the mechanical properties of bitumen is an important goal for road pavements design. For this reason, new compounds are now being sought for testing as bitumen modifiers.In this work, the authors studied the effect that two different chars have on two 50/70 bitumens with different chemical and physical characteristics. A complete morphological, surface and bulk characterization of the two additives was carried out. In addition, rheology, Nuclear Magnetic Resonance (NMR) relaxometry and atomic force microscopy were used to analyze the effect that the two additives exert on the properties of the bitumens. According to the results, the char sample with high porosity could be used as a modifier of mechanical properties, while no rejuvenation effects were observed for either of the two additives tested. In addition, the two additives do not give rise to segregation phenomena.

Colloidal systems are peculiar mixtures formed by the uniform dispersion of sub-micro sized particles of one substance through another substance. In this framework, a particular colloidal system, known as sol, is a colloid in which the dispersed particles are solid, and the dispersing medium is fluid. Sols have extensive applications in industries ranging from material science to food to pharmaceuticals and cosmetics. The size and size distribution of colloidal particles within these systems play a pivotal role in determining their stability, rheological properties, and overall functionality (which in turn directly influence material quality, performance, and shelf life). As a result, this study is aimed at devising a new method to analyze the dimensions of the colloidal particles (dispersed phase) of a colloidal system (sol), like bitumen, by (i) a cheap and common technique, optical microscopy, and (ii) the more complex confocal laser scanning microscopy. To do so, a validation by comparison with a standard technique—in this case, atomic force microscopy is presented. Both optical and confocal microscopies turned out to be suitable, valid, and effective for particle size determination. Both techniques effectively revealed, upon bitumen aging, a shift of the size distribution to slightly larger sizes. Large particles, whose abundance did not increase significantly, appeared to be more inert than small ones. A huge advantage of optical microscopy is its popularity and cost-effectiveness as it is commonly featured in laboratories independently of the research topic. On the other hand, confocal microscopy can observe more particles, thus providing better statistics. It also appears to be more efficient for particles smaller than 1 µm2. These microscopy techniques were used to evaluate the dimensions of the asphaltenes present in a complex colloidal system; bitumen; the model colloidal system for this study, which was examined before and after an aging process which is expected to change the size distribution.

Enhanced oil recovery (EOR) processes are technologies used in the oil and gas industry to maximize the extraction of residual oil from reservoirs after primary and secondary recovery methods have been carried out. The injection into the reservoir of surface-active substances capable of reducing the surface tension between oil and the rock surface should favor its extraction with significant economic repercussions. However, the most commonly used surfactants in EOR are derived from petroleum, and their use can have negative environmental impacts, such as toxicity and persistence in the environment. Biosurfactants on the other hand, are derived from renewable resources and are biodegradable, making them potentially more sustainable and environmentally friendly. The present review intends to offer an updated overview of the most significant results available in scientific literature on the potential application of biosurfactants in the context of EOR processes. Aspects such as production strategies, techniques for characterizing the mechanisms of action and the pros and cons of the application of biosurfactants as a principal method for EOR will be illustrated and discussed in detail. Optimized concepts such as the HLD in biosurfactant choice and design for EOR are also discussed. The scientific findings that are illustrated and reviewed in this paper show why general emphasis needs to be placed on the development and adoption of biosurfactants in EOR as a substantial contribution to a more sustainable and environmentally friendly oil and gas industry.

Road pavement characteristics can be improved by modifying bitumens through addition of fine particles. To avoid environmental issues, attention is recently being paid to bio-materials. In this study, a 50/70 bitumen was modified through the addition of char obtained from the pyrolysis of waste tires. Char addition causes an increase in transition (gel to sol) temperature of up to 4 °C and an increase in rigidity under working conditions (50 °C) of up to about one order of magnitude. The effect of the gas type flowing under the pyrolysis process (CO2, N2 and CO2 + N2) on the mechanical characteristics of the bitumen was also investigated. More marked effects on the rheological performances were found if char coming from pyrolysis under CO2 was used (the gel-to-sol transition temperature is increased by about 4.5 °C) compared to that coming from pyrolysis under N2 (gel-to-sol transition temperature is increased by about 3 °C). The effect is at a maximum for char from CO2 at 3% wt/wt, whereas regarding char from N, a lesser effect is seen with a more uniform (flat) effect as a function of char% and with an increase in gel-to-sol transition temperature of about 3 °C. Coherently, char obtained from pyrolysis under CO2 was found to possess a higher surface area constituted by smaller particles than that coming from pyrolysis under N2. In fact, the BET-specific surface passes 79 m2/g for N2-char to 174 m2/g for CO2-char and the micropore volume fraction increases from 2 to 9. The observed differences can be attributed to the oxidizing environment (CO2) that is more aggressive and reactive in the synthesis phase compared to an inert environment (N2). Char also showed an anti-aging effect, hindering the increase in rigidity typically associated with the aging process. This effect was explained in terms of the compatibility of char with bitumen’s organic nature, and presumably its more effective hosting in a bituminous structure, which is presumably higher when char is produced under CO2 rather than N2. This study quantitatively indicates how a residue derived from the pyrolysis of a waste material can be efficiently re-used to increase the mechanical characteristics of bitumen, accomplishing the recent circular-based needs for environmental protection.

This paper reports the analysis of the intramolecular OH stretching band obtained by Fourier Transform Infrared (FTIR) spectroscopy measurements. In order to characterize the effect of montmorillonite on the properties of Bovine Serum Albumin (BSA) the two-state model is adopted for the analysis of the OH stretching band. We assume that the OH stretching can be divided into two different states of inter-molecular bonding. The results of this experimental work confirm that the montmorillonite leads to a stabilization of the BSA structure. Also, the analysis of the spectra temperature dependence shows a montmorillonite-induced higher thermal stability of the BSA in respect to pristine BSA. Thus, this paper allows to highlight the importance of montmorillonite as thermal bio-protector: this is also evidenced by the theory widely discussed in the following introduction regarding the birth of the first life forms on earth in montmorillonite clay, in which the protective role of the montmorillonite interlayer space is also highlighted. A FTIR analysis was carried out to investigate the interaction of montmorillonite with BSA. Two different approaches, i.e. Spectral Distance and Wavelet analyses, constitute two effective and innovative approaches for the characterization of the thermal properties of pristine BSA and of BSA in the presence of montmorillonite. The results allowed us to consider as BSA in the presence of montmorillonite has a lower spectral sensitivity when the temperature changes and, therefore, the role of montmorillonite as a thermal bio-protector is motivated.

The investigation of the structural features in biological membranes represents a central topic in many aspects of biological science. It involves the study of the collective behavior of a great number of interacting macromolecules, while the study of the structure-function relationship require the observation and calculation of a large number of key factors. The self-assembly processes involved in biomembranes represent the cornerstone of the biological systems functioning, due to the special role of the complex macromolecular assemblies containing lipids, proteins, carbohydrates, nucleic acids, and other active components. In this article, we describe the main techniques and approaches employed for the investigation of biological membranes, which are characterized by a wide range of the space-time domains. The future challenge in this research field must provide the integration of the different research models and approaches into a common background based on multi- and interdisciplinary method that combine the expertise coming from the different disciplines.

Refuse-Derived Fuels (RDFs) are segregated forms of wastes obtained by a combined mechanical–biological processing of municipal solid wastes (MSWs). The narrower characteristics, e.g., high calorific value (18–24 MJ/kg), low moisture content (3–6%) and high volatile (77–84%) and carbon (47–56%) contents, make RDFs more suitable than MSWs for thermochemical valorization purposes. As a matter of fact, EU regulations encourage the use of RDF as a source of energy in the frameworks of sustainability and the circular economy. Pyrolysis and gasification are promising thermochemical processes for RDF treatment, since, compared to incineration, they ensure an increase in energy recovery efficiency, a reduction of pollutant emissions and the production of value-added products as chemical platforms or fuels. Despite the growing interest towards RDFs as feedstock, the literature on the thermochemical treatment of RDFs under pyrolysis and gasification conditions still appears to be limited. In this work, results on pyrolysis and gasification tests on a real RDF are reported and coupled with a detailed characterization of the gaseous, condensable and solid products. Pyrolysis tests have been performed in a tubular reactor up to three different final temperatures (550, 650 and 750 °C) while an air gasification test at 850 °C has been performed in a fluidized bed reactor using sand as the bed material. The results of the two thermochemical processes are analyzed in terms of yield, characteristics and quality of the products to highlight how the two thermochemical conversion processes can be used to accomplish waste-to-materials and waste-to-energy targets. The RDF gasification process leads to the production of a syngas with a H2/CO ratio of 0.51 and a tar concentration of 3.15 g/m3.

The development of innovative teaching methods is an effective way to promote new science education standards, in view of a positive feedback of the student performance. Despite the teachers positive attitudes towards the application of innovative learning approaches, the rapid progress of science and technology in the last decades requests a renewed global approach and a synergistic organization of the educational contents for an efficient teaching of the scientific topics. Modern teaching programs request then an efficient approach which allows to clearly identify the role of each discipline within the complex organization of the novel scientific concepts. In recent years, the progress in soft condensed matter research was driven by modern methods in both the experimental techniques and the theoretical approaches. In this article, we propose a conceptual map for a multidisciplinary approach of the post-graduate programs in soft condensed matter physics, one of the most important field in modern science and technology scene. We highlight the conceptual interconnection and the synergistic relation between different sub-disciplines of the field. The proposed conceptual map may stimulate the exploration of new approaches for the integration of knowledge and skills both from the experimental and theoretical point of view. In this respect teachers can organize scientific curricula by organizing and representing knowledge conceptually, by developing a curriculum that integrates the different (experimental and theoretical) topics appropriately and by designing environments and tasks that support motivation and (interest-based) cooperative learning.

After the Cultural Revolution in the seventeenth century, several poets believed that science was killing the beauty of art and poetry. So, imagination has been believed to be as opposite to scientific method. Fortunately, this point of view has been generally abandoned now, and the important role of imagination in science is finally well recognized. Particularly in the field of material science, the structural and dynamical properties of a system are usually unpredictable from their constituents, since they come generally from the emerging behavior of assemblies constituted by a huge number of building blocks, so imagination is indicated as an essential tool for (i) thinking experiments, (ii) interpretating their results and (iii) preparing novel materials. This makes the topic absolutely fit for a typical flipped classroom approach. Younger students may make their first knowledge of the use of imagination in science by searching for the debates taken place over the centuries: interesting stories, debates and sometimes enjoying aspects can be found, and this can surely trigger interest in the study up to the investigation of modern complex materials. Then, at school, the stories, ideas, and opinions can be consolidated under the coordination of the teacher. In this ambit, it is obvious that interdisciplinarity is a key ingredient which can surely emerge from the activities. With an eye to future perspectives, final comments and examples of modern research activity will be also reported to show how imagination can help in setting up smart procedures to prepare novel materials in modern science.

From the nano-world to solar systems length-scales span over several orders of magnitude. In young student it is therefore hard to fully understand the relative proportions among different objects even belonging to the same level of complexity. Resizing to human-related distances is an effective way to understand the relative distances in astronomic scales or the amount of information contained in a single cell. In general, the use of imagination is essential in educational research as well as the use of different skills in interdisciplinary works. Some appealing example will be given and the result of a pilot learning by doing teaching pathway involving hundreds of young students will be presented. Clues will give indications for future directions in educational research.

It is always a big problem to explain students what radiation is and how it can help researchers in understanding the structure of materials in a clear and simple way. The exact comprehension of radiation has followed a very problematic historical excursus. The problem of understanding what light is started to be faced around the VI century B.C.; since that time, a continuous development of ideas and models has characterized the definition of radiation. After Maxwell's equation, the behaviour of light seemed to be well understood, although further enriched, afterwards, by the discoveries in quantum mechanics. Radiation can give rise to several phenomena when interacting with matter. Thus with a correct comprehension of its origin, radiation can constitute a powerful tool in modern science to probe the structure of materials down to the nano-scale and even lower. In this work, scattering phenomena will be considered as effective examples to propose to young students for probing the structure of materials, since these are usually characterized by hierarchical organization of self-assembled structures at different length scales, from atomic to macroscopic distances. In this complex framework, the concept of characteristic distances is pivotal in defining the structure of a material, and can be easily derived from scattering experiments. In this respect, the efforts made in the last century to understand the origin of radiation turned out to be useful in giving researchers the best tool to characterize a given material, at least from its structural point of view. For this reason, modern didactics must take into account for modern approaches to make people aware of these aspects. If bringing kids and young students closer to these arguments is easily achieved by a "learn by doing" approach, this work, structured from the historical point of view and reporting tickling aspects of the debates taken place among peoples over the centuries, represents an opportunity for an interdisciplinary flipped classroom approach.

In recent years, the development of novel approaches for the formation of lipid nano-formulations for efficient transport of drug molecules in living systems offers a wide range of biotechnology applications. However, despite the remarkable progress in recent methodologies of synthesis that provide a wide variety of solutions concerning the liposome surface functionalization and grafting with synthetic targeting ligands, the action of most liposomes is associated with a number of unwanted side effects diminishing their efficient use in nanomedicine and biotechnology. The major limitation in the use of such versatile and smart drug delivery systems is connected with their limited colloidal stability arising from the interaction with the complex environment and multiform interactions established within the specific biological media. Herein, we review the main interactions involved in liposomes used in drug delivery processes. We also analyze relevant strategies that aim at offering possible perspectives for the development of next-generation of liposomes nanocarriers that are able to overcome the critical issues during their action in complex biological media.

A gold nanoparticles transparent electrode was realized by chemical reduction. This work aims to compare the transparent gold nanoparticles electrode with a more commonly utilized gold-film-coated electrode in order to investigate its potential use as counter-electrode (CE) in dye-sensitized solar cells (DSSCs). A series of DSSC devices, utilizing I−/I3− and Co(III)/(II) polypyridine redox mediators [Co(dtb)3]3+/2+; dtb = 4,4′ditert-butyl-2,2′-bipyridine)], were evaluated. The investigation focused firstly on the structural characterization of the deposited gold layers and then on the electrochemical study. The novelty of the work is the realization of a gold nanoparticles CE that reached 80% of average visible transmittance. We finally examined the performance of the transparent gold nanoparticles CE in DSSC devices. A maximum power conversion efficiency (PCE) of 4.56% was obtained with a commercial I−/I3−-based electrolyte, while a maximum 3.1% of PCE was obtained with the homemade Co-based electrolyte.

This paper considers the effect of aging processes on viscoelastic characteristics of vacuum residue oxidation products modified with crumb rubber. Viscoelastic properties were compared to original bitumen raw material-vacuum residue and vacuum residue oxidation products during short-term and long-term aging. The complex shear modulus of the vacuum residue and its oxidation products decreased with an increase in temperature. Short-term aging resulted in increased shear modulus for all samples.The vacuum residue oxidation product modified with crumb rubber had the maximum values of the rutting parameter and fatigue parameter. There was an expansion of the temperature range of plasticity: for the vacuum residue oxidation product with crumb rubber, its value was 67.2 °C. The curves of the black diagram of the modified vacuum residue oxidation product are shifted towards smaller phase angles with the increase in the shear modulus, which indicates the increase in the stiffness and elasticity of the rubber bitumen binders. The vacuum residue oxidation product modified with crumb rubber corresponded to the rubber bitumen binder of the grade RBB 60/90, according to its physical and mechanical indicators.

Liquids with anisotropic local nanostructures which are able to be oriented by a magnetic field can give birefringence. Usually magnetically-induced birefringence is low owing to the low magnetic energy of molecules and to the averaging effect due to thermal agitation. At the same time, the response is usually very fast given the typical timescales of molecular orientational dynamics (nanoseconds). However, we show that the dibutyl phosphate/propylamine liquid mixture is characterized by an extremely slow response (hours) to the magnetic field and by an intense overall effect (Δn/λ ≈ -0.1m^(-1) at 1 Tesla). This surprising behavior has been interpreted as a manifestation of a novel phenomenon of progressive building up of larger and larger internally ordered hetero-associates driven by the magnetic field and involving strongly interacting amphiphiles.

Tarnishing is a process taking place in silver surface causing corrosion. This is due to the presence in the atmosphere, even in small amounts, of reactive species like water, sulphidric acid and carbonyl sulphide which can be physisorbed onto the silver surface thus reacting with it. We propose the use of alkylphosphates to protect the silver surface against corrosion: the polar head group should interact with the silver surface with the formation of a thin film of opportunely oriented surfactant molecules. This would shield the silver surface from the attack of reactive agents present in the atmosphere and from the adsorption of humidity water helped by the surfactant scarce hydrophilicity. The joint Raman and XPS experiments showed the protective action exerted by dibutylphosphate or bis (2-etylhexyl) phosphate according to the different sulphidizing conditions. Our discovery deserves to be tailored in cultural heritage where silver artefacts are generally precious and inimitable objects, but also in modern microelectronics where silver joints and conductors are used.

In recent years the development of novel approaches for the production of nano-formulations (nanocarriers) for efficient transport of drug molecules in living systems offers a wide range of biotechnology applications. However, despite the remarkable developments of recent synthetic methodologies, most of all nanocarrier’s action is associated with a number of unwanted side effects that diminish their efficient use in nanomedicine. This highlights some critical issues in the design and engineering of nanocarrier systems for biotechnology applications, arising from the complex environment and multiform interactions established within the specific biological media. Many questions still remain open for what concerns the way to deal with the complexity of the biological processes involved. What is the minimal number of key parameters (and their related key factors) required to describe behavior of nanomaterials without sacrificing the complexity of the identified process? In other words, what is the “minimum level of complexity” to assume in the theoretical and experimental models that may satisfactorily describe the nanocarriers (and nanomaterials) interaction with biological systems. Herein, we analyze relevant open questions with the aim of offering possible perspectives for the development of next-generation nanomaterials that are able to overcome the critical issues during their action in complex biological media.

In the present paper an approach concerning the formalism of time dependent Pair Correlation Functions (PCF), which characterize the time-space properties of material systems and their Fourier Transforms (FT) is presented. In particular, the effects of the system-probe interaction are dealt by taking into account the coupling between the system properties, through the PCF, and the instrument response function, through its resolution function. Such an approach shows the effects of the instrumental resolution function on the time dependent PCF and on its FT. It emerges that the system dynamics that occurs on a time scale longer than the instrumental energy resolution, is entirely summed up in the elastic contribution whereas the system dynamics on a time scale shorter than the instrumental energy resolution is weighted by the resolution function. As a consequence, by changing the instrumental resolution one can register a crossover between a condition dominated by the elastic contribution to a condition dominated by the quasi-elastic contribution; this occurs when the system relaxation time matches the instrumental resolution time. This procedure reveals to be useful for the analysis of elastic and quasi-elastic signals.

Ionic liquids (ILs) are liquid materials at room temperature with an ionic intrinsic nature. The electrostatic interactions therefore play a pivotal role in dictating their inner structure, which is then expected to be far from the traditional pattern of classical simple liquids. Therefore, the strength of such interactions and their long-range effects are responsible for the ionic liquid high viscosity, a fact that itself suggests their possible use as lubricants. More interestingly, the possibility to establish a wide scenario of possible interactions with solid surfaces constitutes a specific added value in this use. In this framework, the ionic liquid complex molecular structure and the huge variety of possible interactions cause a complex aggregation pattern which can depend on the presence of the solid surface itself. Although there is plenty of literature focusing on the lubricant properties of ionic liquids and their applications, the aim of this contribution is, instead, to furnish to the reader a panoramic view of this exciting problematic, commenting on interesting and speculative aspects which are sometimes neglected in standard works and trying to furnish an enriched vision of the topic. The present work constitutes an easy-to-read critical point of view which tries to interact with the imagination of readers, hopefully leading to the discovery of novel aspects and interconnections and ultimately stimulating new ideas and research.

For asphalt concrete preparation in laboratory mix-design operations, bitumens are usually mixed with micrometer-sized particles (filler), sand and centimeter-sized crushed stones in a gyratory press at a temperature of about 140–155 °C depending on the bitumen viscosity, until adequate homogenization and compaction take place (air voids optimum). This requires energy consumption. To minimize it, the process needs to be optimized and is usually made empirically. The aim of this manuscript is to gain a comprehension of the physico-chemical mechanisms involved in the process by exploring: (i) the rheological properties (viscosity, activation energy) of a neat and RTFOT-aged bitumen, in presence and in absence of a filler, (ii) the volumetric and resistance behavior under the compaction in a standard Gyratory Compactor (GC) of their blends with aggregates and (iii) the mechanical properties (Indirect Tensile Strength, compression and tensile deformation) of the final products. Correlations between activation energy and pre-exponential factor of the viscosity on a side, and between viscosity, workability and final mechanical properties on the other side allowed to provide a rational interpretation of the physico-chemical processes involved in the framework of the physics of complex fluids. The scientific clues will be of help in optimizing the workability in asphalt concretes productions with obvious repercussions in terms of energy savings, useful for economic and environmental issues.

Scattering techniques represent non-invasive experimental approaches and powerful tools for the investigation of structure and conformation of biomaterial systems in a wide range of distances, ranging from the nanometric to micrometric scale. More specifically, small-angle X-rays and neutron scattering and light scattering techniques represent well-established experimental techniques for the investigation of the structural properties of biomaterials and, through the use of suitable models, they allow to study and mimic various biological systems under physiologically relevant conditions. They provide the ensemble averaged (and then statistically relevant) information under in situ and operando conditions, and represent useful tools complementary to the various traditional imaging techniques that, on the contrary, reveal more local structural information. Together with the classical structure characterization approaches, we introduce the basic concepts that make it possible to examine inter-particles interactions, and to study the growth processes and conformational changes in nanostructures, which have become increasingly relevant for an accurate understanding and prediction of various mechanisms in the fields of biotechnology and nanotechnology. The upgrade of the various scattering techniques, such as the contrast variation or time resolved experiments, offers unique opportunities to study the nano- and mesoscopic structure and their evolution with time in a way not accessible by other techniques. For this reason, highly performant instruments are installed at most of the facility research centers worldwide. These new insights allow to largely ameliorate the control of (chemico-physical and biologic) processes of complex (bio-)materials at the molecular length scales, and open a full potential for the development and engineering of a variety of nano-scale biomaterials for advanced applications.

Asphalt concretes are materials used worldwide. It is well-known that in such materials the minor component, the bitumen, plays the most important role since it binds the high fraction (>95%) of inorganic macrometer-sized particles ensuring a coherent material fit for uses in road pavement. Additives can be used to increase the overall rheological properties, with high benefits in terms of resistance to mechanical stress and to ageing. Among these, nanoparticles have recently been considered as very effective additives in increasing the overall performance, increasing the viscosity, the rutting parameter and the recovery from deformation. However, they are expensive, so a delicate equilibrium between costs and benefits must be found for large-scale uses. In this framework, we furnish our critical analysis of the state-of-the art technologies used for improving the bitumen performances by means of nanoparticles with an eye to eventual added-values (like anti-oxidant effect, antistripping properties, or UV radiation screening which avoids radiation-induced ageing…). We will critically consider the costs involved in their use and we will give our opinion about vanguard techniques which can be fit for the analysis of nanoparticles-containing bitumens and asphalts. Interesting perspectives will be also given for future research and applications.

The asphalt industry’s incentive to reduce greenhouse gas emissions has increased since the 1990s due to growing concerns on environmental issues such as global warming and carbon footprint. This has stimulated the introduction of Warm Mix Asphalt (WMA) and its technologies which serve the purpose of reducing greenhouse gas emissions by reducing the mixing and compaction temperatures of asphalt mix. WMA gained popularity due to the environmental benefit it offers without compromising the properties, performance and quality of the asphalt mix. WMA is produced at significantly lower temperatures (slightly above 100 °C) and thus results in less energy consumption, fewer emissions, reduced ageing, lower mixing and compaction temperatures, cool weather paving and better workability of the mix. The latter of these benefits is attributed to the incorporation of additives into WMA. These additives can also confer even better performance of WMA in comparison to conventional Hot Mix Asphalt (HMA) methods. Even though there are recommended dosages of several WMA additives, there is no general standardized mixture design procedure and this makes it challenging to characterize the mechanism(s) of action of these additives in the warm mix. The effects of the addition of additives into WMA are known to a reasonable extent but not so much is known about the underlying interactions and phenomena which bring about the mechanism(s) by which these additives confer beneficial features into the warm mix. Additives in a certain way are being used to bridge the gap and minimize or even nullify the effect of the mixing temperature deficit involved in WMA processes while improving the general properties of the mix. This review presents WMA technologies such as wax, chemical additives and foaming processes and the mechanisms by which they function to confer desired characteristics and improve the durability of the mix. Hybrid techniques are also briefly mentioned in this paper in addition to a detailed description of the specific modes of action of popular WMA technologies such as Sasobit, Evotherm and Advera. This paper highlights the environmental and technical advantages of WMA over the conventional HMA methods and also comprehensively analyzes the mechanism(s) of action of additives in conferring desirable characteristics on WMA, which ultimately improves its durability.

Magnetically-induced birefringence is usually low in molecular liquids owing to the low magnetic energy of molecules with respect to the thermal one. Despite this, it has been found that a mixture of dibutyl phosphate and propylamine at propylamine molar ratio (X) around 0.33 surprisingly gives an intense effect (∆n/λ ≈ −0.1 at 1 Tesla). In this paper the time- and intensity- response to the magnetic field of such mixture have been studied. It was found that the reaction to the magnetic field is unusually slow (from several minutes to hours) depending of the magnetic field intensity. On the basis of the data, the model of orientable dipoles dispersed in a matrix enables to interpret the magnetic field-induced self-assembly in terms of soft molecules-based nanostructures. The analogy with systems made of magnetically polarizable (solid or soft) particles dispersed in liquid carrier allows understanding, at the microscopic scale, the molecular origin and the supra-molecular dynamics involved in the observed behavior. The data present a novel phenomenon in liquid phase where the progressive building up/change of ordered and strongly interacting amphiphiles is driven by the magnetic field.

This review aims to explore the state of the knowledge and the state-of-the-art regarding bitumen rejuvenation. In particular, attention was paid to clear things up about the rejuvenator mechanism of action. Frequently, the terms rejuvenator and flux oil, or oil (i.e., softening agent) are used as if they were synonymous. According to our knowledge, these two terms refer to substances producing different modifications to the aged bitumen: they can decrease the viscosity (softening agents), or, in addition to this, restore the original microstructure (real rejuvenators). In order to deal with the argument in its entirety, the bitumen is investigated in terms of chemical structure and microstructural features. Proper investigating tools are, therefore, needed to distinguish the different mechanisms of action of the various types of bitumen, so attention is focused on recent research and the use of different investigation techniques to distinguish between various additives. Methods based on organic synthesis can also be used to prepare ad-hoc rejuvenating molecules with higher performances. The interplay of chemical interaction, structural changes and overall effect of the additive is then presented in terms of the modern concepts of complex systems, which furnishes valid arguments to suggest X-ray scattering and Nuclear Magnetic Resonance relaxometry experiments as vanguard and forefront tools to study bitumen. Far from being a standard review, this work represents a critical analysis of the state-of-the-art taking into account for the molecular basis at the origin of the observed behavior. Furnishing a novel viewpoint for the study of bitumen based on the concepts of the complex systems in physics, it constitutes a novel approach for the study of these systems.

Amphiphiles are synthetic or natural molecules with the ability to self-assemble into a wide variety of structures including micelles, vesicles, nanotubes, nanofibers, and lamellae. Self-assembly processes of amphiphiles have been widely used to mimic biological systems, such as assembly of lipids and proteins, while their integrated actions allow the performance of highly specific cellular functions which has paved a way for bottom-up bionanotechnology. While amphiphiles self-assembly has attracted considerable attention for decades due to their extensive applications in material science, drug and gene delivery, recent developments in nanoscience stimulated the combination of the simple approaches of amphiphile assembly with the advanced concept of supramolecular self-assembly for the development of more complex, hierarchical nanostructures. Introduction of stimulus responsive supramolecular amphiphile assembly-disassembly processes provides particularly novel approaches for impacting bionanotechnology applications. Leading examples of these novel self-assembly processes can be found, in fact, in biosystems where assemblies of different amphiphilic macrocomponents and their integrated actions allow the performance of highly specific biological functions. In this perspective, we summarize in this tutorial review the basic concept and recent research on self-assembly of traditional amphiphilic molecules (such as surfactants, amphiphile-like polymers, or lipids) and more recent concepts of supramolecular amphiphiles assembly which have become increasingly important in emerging nanotechnology.

Due to the wide variation in geographic and climatic conditions, the search for high-performance bituminous materials is becoming more and more urgent to increase the useful life of pavements and reduce the enormous cost of road maintenance. Extensive research has been done by testing various bitumen modifiers, although most of them are petroleum-derived additives, such as polymers, rubbers and plastic, which in turn do not prevent oxidative aging of the binder. Thus, as an alternative to the most common polymeric rheological modifiers, selected binder additives falling in the categories of organosilane (P2KA), polyphosphoric acid (PPA) and food grade phospholipids (LCS) were homogeneously mixed to a base bitumen. The goal was to analyse the micro-morphology of the bitumens (neat and modified) subjected to different cooling rates and to find the corresponding correlations in the mechanical response domain. Therefore, microstructural investigations carried out by Atomic Force Microscopy (AFM) and fundamental rheological tests based on oscillatory dynamic rheology, were used to evaluate the effect of additives on the bitumen structure and compared with pristine binder as a reference. The tested bitumen additives have been shown to elicit different mechanical behaviours by varying the cooling rate. By comparing rheological data, analysed in the framework of the “weak gel” model, and AFM images, it was found that both P2KA and PPA altered the material structure in a different manner whereas LCS revealed superior performances, acting as “mechanical buffer” in the whole explored range of cooling rates.

Electrospray ionization (ESI) is a widely adopted soft ionization method for mass spectroscopy (MS). In spite of the undeniable success of the technique, its mechanisms are difficult to be analytically modelled because the process is characterized by non-equilibrium conditions. The common belief is that the formation of gas-phase ions takes place at the apex of the Taylor cone via electrophoretic charging. The charge balance implies that a conversion of electrons to ions should occur at the metal-liquid interface of the injector needle. We have detected that the above description is based on unproved assumptions which are not consistent with the correct evaluation of the problem. The comparison between experiments performed under the usual geometry and observations obtained under symmetric field configurations suggests that the emitted droplets cannot be significantly charged or, at least, that any possible ionization mechanism is so poorly efficient to ensure that columbic forces cannot play a major role in jet formation, even in cases where the liquid consists of a solution of ionic species. Further work is required to clearly understand how ionization occurs in ESI-MS.

The development of smart nanocarriers for the delivery of therapeutic drugs has experienced considerable expansion in recent decades, with the development of new medicines devoted to cancer treatment. In this respect a wide range of strategies can be developed by employing liposome nanocarriers with desired physico-chemical properties that, by exploiting a combination of a number of suitable soft interactions, can facilitate the transit through the biological barriers from the point of administration up to the site of drug action. As a result, the materials engineer has generated through the bottom up approach a variety of supramolecular nanocarriers for the encapsulation and controlled delivery of therapeutics which have revealed beneficial developments for stabilizing drug compounds, overcoming impediments to cellular and tissue uptake, and improving biodistribution of therapeutic compounds to target sites. Herein we present recent advances in liposome drug delivery by analyzing the main structural features of liposome nanocarriers which strongly influence their interaction in solution. More specifically, we will focus on the analysis of the relevant soft interactions involved in drug delivery processes which are responsible of main behaviour of soft nanocarriers in complex physiological fluids. Investigation of the interaction between liposomes at the molecular level can be considered an important platform for the modeling of the molecular recognition processes occurring between cells. Some relevant strategies to overcome the biological barriers during the drug delivery of the nanocarriers are presented which outline the main structure-properties relationships as well as their advantages (and drawbacks) in therapeutic and biomedical applications.

We review the most advanced methods for the fabrication of cathodes for dye-sensitized solar cells employing nanostructured materials. The attention is focused on metal nanoparticles and nanostructured carbon, among which nanotubes and graphene, whose good catalytic properties make them ideal for the development of counter electrode substrates, transparent conducting oxide, and advanced catalyst materials.