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When asphalt pavement is in practical use, it is prone to cracking and other diseases due to the long-term effects of load and climate and the restricted self-healing properties of the asphalt material. In order to improve the properties and durability of asphalt pavement, we introduced disulfide bonds into polyurethane (PU) in this study. We prepared polyurethane-modified asphalt (PUA) containing dynamic disulfide covalent bonds using polytetrahydrofuran (PTMG), polyethylene adipate (PEA), and hydroxyl-terminated polybutadiene (HTPB) as soft segments. Subsequently, the rheological properties, healing performance, and microstructure of the PUA were studied. The results indicated that the PU with disulfide bonds was integrated into the asphalt and had good dispersity. A cross-linked network structure formed between them. PUA with HTPB as the soft segment had excellent high-temperature deformation and low-temperature cracking resistance and a prominent advantage in durability. In comparison, PUA synthesized with PEA had better high-temperature performance and fatigue resistance, and PUA synthesized with PTMG had considerable low-temperature properties and stability. The disulfide bonds had a positive impact on the high-temperature performance, aging resistance, and healing properties of PUA through constant dynamic exchange and topological rearrangement effects. This study provides a reference for the preparation of PUA with ideal self-healing ability and has instructive significance for the selection of soft segment materials for synthesizing PUA. [ABSTRACT FROM AUTHOR]

In order to study the effects of molding process on the macroscopic performances of cement stabilized gravel, based on two kinds of gradation of skeleton compaction and suspension compaction, eight kinds of cement stabilized gravel were prepared by four kinds of processes: static compaction molding with forced mixing, vibratory compaction with forced mixing, static compaction molding with vibratory mixing, and vibratory compaction with vibratory mixing. Furthermore, the macro-performances of cement stabilized gravel were investigated by adopting the 7 d unconfined compression test, the 28 d single-axis penetration test, the 7 d warming shrinkage test, and the 7 d drying shrinkage test. The underlying microscopic mechanism of the macroscopic property variation of the cement stabilized gravel was analyzed by combining with the microscopic means of scanning electron microscope. The results show that the mechanical properties of cement stabilized gravel with skeleton dense grading under vibration mixing and vibration compaction process are optimal, and its 7 d unconfined compressive strength and 28 d uniaxial compression modulus are improved by 169. 5% and 97. 2%, respectively, compared with that of forced mixing and static compression molding. The vibration mixing vibration compaction techniques can improve the macro performance of cement stabilized crushed stone in terms of promoted the cement hydration product generation, perfect structure, and elevated overall uniformity. [ABSTRACT FROM AUTHOR]

There are still some deficiencies in the development and applications of epoxy asphalt materials, and the chemistry and curing mechanism of epoxy asphalt materials remain unknown. Based on the curing mechanism of commercial epoxy asphalt, an oleylamine curing epoxy asphalt (OCEA) material was prepared, and it was systematically described from the perspective of engineering application and reaction mechanism. The viscosity properties of OCEA were mainly used to predict its reserved time range and temperature during construction. The tensile properties of OCEA and commercial epoxy asphalt are evaluated to show the mechanical properties. The fluorescence microscopy and infrared spectroscopy of the OCEA were analyzed to understand its micromorphology and curing mechanism, and its current advantages are further explained in combination with the tensile properties of OCEA. The results show that the OCEA has the advantage of high strength and toughness. The asphalt phase can participate in the curing reaction of epoxy resin, enhancing the miscibility between constituents, which further enhances the miscibility of the asphalt binder and epoxy resin. This study can provide new materials for engineering epoxy asphalt and implications for further research on epoxy asphalt materials. [ABSTRACT FROM AUTHOR]

Sodium chalcogenide compounds, glassy and crystalline, are promising materials for a number of potential applications in non-linear optics (NLO), photovoltaic, and energy conversion and storage. This work deals with the study of the newly synthesized glasses in the Na2Se–As2Se3 chalcogenide system as well as the corresponding ternary crystals, NaAsSe2 and Na3AsSe3. We examine the glass-forming domain in the pseudo-binary system using melt-quenching and mechanical milling techniques. We also analyse the macroscopic and electrical properties of the glasses in comparison with their crystalline counterparts, and the annealed glasses yielding glassy/crystalline alloys.

Understanding the relationship between biodiversity and ecosystem functioning (BEF) is essential to comprehend the impacts of biodiversity changes on ecosystem functioning. This knowledge helps to detect and anticipate significant trends in global biodiversity loss and the homogenization of biota worldwide to prevent them. Species act together with climate, resource availability, and disturbance regimes to modulate ecological processes defining ecosystems' complexity and their dynamic adaptation to variability. In this article, we revisit the BEF paradigm by addressing current knowledge of how biodiversity connects to ecosystem functioning across scales in the context of complex adaptive systems (CAS). We focus on ecosystem processes that lead to the emergence of the BEF relationship, considering ecosystem functioning as a macroscopic emergent property. Specifically, this work integrates the knowledge of the processes that connect biodiversity to ecosystem functioning. It addresses how biodiversity supports ecosystem multifunctionality across scales, resulting in the persistence of CAS in a rapidly changing world. We present a framework for ecological management considering the BEF relationship within the scope of CAS. The CAS standpoint brings new insights into the BEF field and its relevance for future ecological conservation of the Earth's life support. [ABSTRACT FROM AUTHOR]

In the study of deep geological disposal of high‐level radioactive waste (HLW), beta decay has been widely studied, whereas the nuclear transmutation effects due to beta decay on vitrification are generally neglected. In this work, a series of sodium borosilicate glasses doped with cesium was fabricated. The nuclear transmutation due to beta decay evolving with the deposited time was simulated by substituting for cesium with barium. The macroscopic properties of the glasses, including density, hardness, and Young's modulus, were measured using the Archimedes (buoyancy) method and nanoindentation, respectively. The microscopic structures of the glasses were characterized by grazing incident X‐ray diffraction, infrared spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, and Raman spectroscopy. The nuclear transmutation effects were significant. With the substitution of barium for cesium, the density, hardness, and modulus of the glasses increased and eventually tended to saturation. A decrease of [BO3] units and an increase of [BO4] units were observed in the infrared spectra and NMR spectra. In addition, the results were systematically compared to previous strontium‐doping work in order to evaluate nuclear transmutation effects due to beta decay on vitrification in HLW comprehensively. The comparison demonstrated that the nuclear transmutation effect of cesium is completely opposite to that of strontium. The research is expected to contribute to a deeper understanding on the nuclear transmutation effects due to beta decay in HLW on vitrification. [ABSTRACT FROM AUTHOR]

In this paper, the combined magnetic-vibration treatment purposed to reduce residual stress is evaluated. In combination with the single magnetic and vibration treatment, a comparison is performed after stress reduction in terms of the reduction effect, macroscopic properties, and metal properties of the material. According to the experimental results, different treatment methods can reduce the residual stress. Besides, the longitudinal residual stress was reduced more significantly than the transverse residual stress, and the combined magnetic-vibration treatment performed significantly better in reducing residual stress than either vibration or magnetic alone. After the adjustment of different treatments, the tensile strength showed a slight reduction, but the elongation was improved, with the mechanical properties reaching the optimum level after the combined magnetic-vibration treatment. The conductivity was improved, and the combined magnetic-vibration treatment led to a significant improvement. After the vibration and magnetic treatment were adjusted, the hardness was basically unchanged, despite a significant improvement of hardness after the combined magnetic-vibration treatment. The magnetic performance was improved after the adjustment of different treatment, and the combined magnetic-vibration treatment led to a significant improvement. The metallographic results show that the reduction of precipitated phases and the narrowing of grain boundaries caused by using different control methods may be the main influencing factors in the properties of the material. Moreover, after the combined magnetic-vibration treatment, there were more significant changes in the reduction of precipitated phases and the narrowing of grain boundaries. [ABSTRACT FROM AUTHOR]

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In the present work, a microscopic traffic flow model using Cellular Automata is proposed. The model is intended to explain accurately the lane changing activity, which is treated as a continuous process rather than a discrete event as suggested by previous models. Various important properties of traffic flow could be explained by the proposed model and the simulated results are quite reasonable. The proposed model can give explanation to the microscopic properties, like, local stability, asymptotic stability, closing-in/shying-away and insensitivity of safe distance headway to perturbation pattern, initial distance headway and initial speed. Macroscopic properties like speed, flow and density were studied for a traffic stream under various conditions like varying road width. The results obtained from simulation of single lane and wide roads with lane discipline match closely to the values suggested by Highway Capacity Manual. [ABSTRACT FROM AUTHOR]

Understanding the relationship between biodiversity and ecosystem functioning (BEF) is essential to comprehend the impacts of biodiversity changes on ecosystem functioning. This knowledge helps to detect and anticipate significant trends in global biodiversity loss and the homogenization of biota worldwide to prevent them. Species act together with climate, resource availability, and disturbance regimes to modulate ecological processes defining ecosystems’ complexity and their dynamic adaptation to variability. In this article, we revisit the BEF paradigm by addressing current knowledge of how biodiversity connects to ecosystem functioning across scales in the context of complex adaptive systems (CAS). We focus on ecosystem processes that lead to the emergence of the BEF relationship, considering ecosystem functioning as a macroscopic emergent property. Specifically, this work integrates the knowledge of the processes that connect biodiversity to ecosystem functioning. It addresses how biodiversity supports ecosystem multifunctionality across scales, resulting in the persistence of CAS in a rapidly changing world. We present a framework for ecological management considering the BEF relationship within the scope of CAS. The CAS standpoint brings new insights into the BEF field and its relevance for future ecological conservation of the Earth’s life support.

This paper experimentally examines variations in the macroscopic properties of concrete under the interaction of early-age temperature and salt ion corrosion and investigates the microscopic mechanism of these variations from the perspective of pore structure and microcracks. The results show a prominent initial defect compaction stage of the compressive stress–strain curves of the specimens under the interaction of two factors, an increase in the number of pores and a high degree of crack development. Accordingly, the peak strength, secant elastic modulus and porosity of the specimens are greatly affected by the interaction between early-age temperature and salt ion corrosion, as reflected by the obvious deterioration trend. Based on a theoretical analysis, the concept of the initial defect strain ratio is proposed, the relationship between the total deformation and two indicators (initial defect deformation and matrix deformation) is clarified, and a constitutive model that reflects the initial defect compaction characteristics is established. [ABSTRACT FROM AUTHOR]

In more accurately simulating the degradation process of cast-in-place concrete structures in saline soil areas, this study prepared sulfate saline soil with varying sulfate concentrations. Experiments were conducted by casting concrete with different water-to-binder ratios and cement types into the saline soil. Through the analysis of macroscopic properties evolution and microstructure of early-age concrete, the study revealed the degradation mechanism of concrete in a sulfate saline soil environment. The investigation identified sulfate attack and leaching as the primary causes of early-age concrete degradation in sulfate saline soil. Notably, preparing concrete in saline soil exacerbated the degradation process. The macroscopic properties of some concrete begin to decrease as early as 1 day. The content of ettringite within concrete is gradually increasing and the content of portlandite is decreasing with age. At 28 days, the concrete corrosion interface displayed ettringite with varying widths and morphologies within pores and cracks, while the concrete surface layer exhibited micro-cracks and a porous surface. In addition, effective mitigation of early-age concrete degradation in saline soil can be achieved by controlling the water-to-binder ratio and utilizing cement with a lower tricalcium aluminate content. • The properties of early-age concrete in saline soil were methodically studied. • Sulfate attack and leaching are major causes of early-age concrete deterioration. • Lowering w / c or utilizing low C 3 A cement can ease early-age concrete deterioration. [ABSTRACT FROM AUTHOR]

Lead thioarsenate glasses are promising materials for a number of potential applications in far infrared optics, chemical sensing, nonlinear photonics, etc. Electronic properties of the PbS–As2S3 glasses were studied in the past, however, the relationship between the glass and crystal characteristics have not been established. Here we compare the glass‐forming domain in the pseudo‐binary system obtained by usual melt–quenching and mechanical milling. Macroscopic and electrical glass properties are analyzed in comparison with their crystalline counterparts: PbAs2S4, Pb5As9S18, and Pb2As2S5, and the annealed glasses yielding glassy/crystalline alloys. Although the primary crystallization phases in glasses are consistent with the phase diagram, the lead local environment seems to be different in glasses and crystals, reflected by their properties and preliminary high‐energy X‐ray diffraction results. [ABSTRACT FROM AUTHOR]

This study investigated the hydraulic conductivity and microscopic properties of two backfills, conventional sand/bentonite (SB) and sand/xanthan gum (XG)-amended bentonite/sand (XG-SB), for use in vertical cutoff walls for controlling lateral migration of lead-contaminated groundwater. A series of laboratory experiments were conducted on the two backfills to assess slump height, specific gravity, liquid limit, and hydraulic conductivity using distilled water, tap water, and lead nitrate [Pb(NO3)2] solutions at different concentrations. The results showed that the moisture content corresponding to the target slump height was higher for XG-amended backfill as compared with unamended backfill. XG amendment slightly decreased specific gravity (Gs), but substantially increased liquid limit (wL) of the backfill. An increase in concentration of Pb(NO3)2 solution increased Gs , but decreased wL for both unamended and XG-amended backfills. The hydraulic conductivity (k) of both backfills increased with increasing concentrations of Pb(NO3)2 solutions. XG-amended backfill hydraulic conductivity (k) was found to be less than 10−9 m/s regardless of type of permeating liquid, whereas unamended backfill k was found to be higher than 10−9 m/s when permeated with Pb(NO3)2 solutions. Scanning electron microscopy (SEM) coupled with energy-dispersive spectrometry (EDS) analyses indicated that XG hydrogels filled the intergranular pores of XG-amended backfill and formed a thin coating over the bentonite particles and bentonite-coated sand granules. The X-ray diffraction (XRD) results showed no intercalation of XG into montmorillonite platelets. The zeta potential of XG-amended bentonite was higher negative relative to unamended bentonite. The microscopic properties elucidated the mechanisms for superior hydraulic performance of XG-amended backfill. A comprehensive comparison of k for conventional backfill and polymer-amended backfills based on this study and previously published studies revealed that the bentonite content, bentonite type, effective confining stress, and cation concentration of a permeating liquid can significantly affect the k of the backfills. [ABSTRACT FROM AUTHOR]

A large-scale computational model of the basal ganglia network and thalamus is proposed to describe movement disorders and treatment effects of deep brain stimulation (DBS). The model of this complex network considers three areas of the basal ganglia region: the subthalamic nucleus (STN) as target area of DBS, the globus pallidus, both pars externa and pars interna (GPe-GPi), and the thalamus. Parkinsonian conditions are simulated by assuming reduced dopaminergic input and corresponding pronounced inhibitory or disinhibited projections to GPe and GPi. Macroscopic quantities are derived which correlate closely to thalamic responses and hence motor programme fidelity. It can be demonstrated that depending on different levels of striatal projections to the GPe and GPi, the dynamics of these macroscopic quantities (synchronisation index, mean synaptic activity and response efficacy) switch from normal to Parkinsonian conditions. Simulating DBS of the STN affects the dynamics of the entire network, increasing the thalamic activity to levels close to normal, while differing from both normal and Parkinsonian dynamics. Using the mentioned macroscopic quantities, the model proposes optimal DBS frequency ranges above 130 Hz. [ABSTRACT FROM AUTHOR]

Dairy products are among the most popular nutritious foods in the world. Understanding the relationship between the composition, process, and structural properties at different scales (molecular, microscopic, and macroscopic) is fundamental to designing dairy products. This review highlights the need to analyze this relationship from different scales as an essential step during product design through a multiscale approach.

• The intermediate state of P 2 O 5 dissolved in molten slags was studied by molecular dynamics simulation. • The influence of CaO content on the microstructure and properties of molten melt was studied. • The microstructure transformation mechanism of phosphate clusters was illustrated. The microstructure of dephosphorization slag determines its macroscopic properties. Dephosphorization process affects the dissolution of P 2 O 5 in the slag and changes the dephosphorization conditions. In this paper, molecular dynamics simulation was used to study the effect of composition on the microstructure and macroscopic properties of CaO-P 2 O 5 binary system, which have a significance effect on the dissolution mechanism of P 2 O 5 in slag in the steelmaking field. The microstructure of the melt was described by radial distribution function, cluster proportion, bond angle distribution and so on. The diffusion coefficient, viscosity, thermal conductivity and surface tension were calculated to describe the macroscopic properties of the molten slags. The results show that the P-O bond length changes from 1.45 to 1.55 as the content of CaO increases from 50 % to 70 %. The planar [PO 3 ]- anions gradually transform into tetrahedral [PO 4 ]3- anions with increasing X CaO , and finally the [PO 4 ]3- clusters occupy the majority. Ca exists as free cation and plays the role of charge complement in molten CaO-P 2 O 5 melt. The order of diffusion ability of elements is O2– > Ca2+ > P5+ as X CaO increases from 50 % to 70 %. The viscosity of the system tends to decrease. The dilution of P-O clusters is enhanced with the increase of X CaO. The thermal conductivity and surface tension shows an upward trend. [ABSTRACT FROM AUTHOR]

The repeated wetting–drying (WD) cycles can cause the deterioration of rock and thus affect the service performance of the related rock engineering, e.g., the crushed-rock embankment and the reservoir. The study comprehensively investigated the deterioration mechanism of sandstone under the WD cycles based on a series of multi-scale experiments, including the microstructure, the meso–micro pore characteristics, and the macroscopic physical and mechanical properties. The results indicate that the content of dissolved minerals and the permeability are two key factors that determine the deterioration effect caused by the WD cycles. During the WD cycles, the pore size range of sandstone becomes wider due to the formation of new small pores and the connection of original pores. Thus, low-density area forms within the samples, which causes the increasing of density dispersion. The structure deterioration weakens the physical and mechanical properties of the samples. The ultrasonic test indicates that the decreasing rate of the P-wave velocity is larger than that of the S-wave velocity, especially in the first 5 cycles. Besides, the exponential equations of uniaxial compressive strength and elastic modulus with the number of WD cycles are established to describe the deterioration of mechanical characteristics. [ABSTRACT FROM AUTHOR]

In recent years, DNA has emerged as a fascinating building material to engineer hydrogel due to its excellent programmability, which has gained considerable attention in biomedical applications. Understanding the structure-property relationship and underlying molecular determinants of DNA hydrogel is essential to precisely tailor its macroscopic properties at molecular level. In this review, the rational design principles of DNA molecular networks based on molecular dynamics of polymers on the temporal scale, which can be engineered via the backbone rigidity and crosslinking kinetics, are highlighted. By elucidating the underlying molecular mechanisms and theories, it is aimed to provide a comprehensive overview of how the tunable DNA backbone rigidity and the crosslinking kinetics lead to desirable macroscopic properties of DNA hydrogels, including mechanical properties, diffusive permeability, swelling behaviors, and dynamic features. Furthermore, it is also discussed how the tunable macroscopic properties make DNA hydrogels promising candidates for biomedical applications, such as cell culture, tissue engineering, bio-sensing, and drug delivery., (© 2023 Wiley-VCH GmbH.)

The article presents models of superelastic hardening of materials with unstable phase structure at a constant temperature. The kinetic equation of the process of formation and growth of spherical nuclei of a new phase is formulated depending on the level of development of inelastic structural deformations, according to which the new phase first represents separate inclusions from embryos, developing it forms the structures of the matrix mixture in the form of interpenetrating skeletons, and finally the new phase is transformed in a matrix with separate inclusions from the material of the remains of the old phase. The influence of structural deformations on the features of phase transformations and nonlinear hardening of inhomogeneous unstable materials with different degree of connectivity of the constituent phases is studied. Various variants of the microstructure material formed in the conditions of the phase transition in the form of separate inclusions and in the form of interpenetrating components are considered. New macroscopic determining relationships for unstable microinhomogeneous materials are established and their effective elastic moduli are calculated. Macroscopic conditions of direct and inverse phase transitions are obtained, their effective limits and hardening coefficients are calculated. It is shown that the values of the macroscopic elasticity moduli of the obtained models lie inside the fork of the lower and upper Hashin-Shtrikman boundaries. Numerical analysis of the developed models has shown good agreement with known experimental data.

： In order to study the effect of microstructure characteristics on the macroscopic properties of axial braided C/C composites ? the macroscopic properties prediction model of the composites was established by combining the homogenization method，the energy method and the FEM. In combination with Python language?a geometric model satisfying the distri­bution law of microstructure characteristics of mesoscopic component material was genera­ted? and its stiffness properties were determined with the help of FEM and experimental re­sults? which was used as the parameters input for the prediction of macroscopic properties. The prediction model was used to predict the macroscopic properties of the material，which was in good agreement with the experimental results. By predicting the properties of materi­als with different braided spacing and fiber rod diameter,the variation of the properties with braided spacing and fiber rod diameter was obtained. The research methods and results in this paper can provide important reference for the process optimization and rational application of composite materials. [ABSTRACT FROM AUTHOR]

• Simple linear mixture rules do not apply for all binary mixtures. • A non-linear dependence of powder properties on composition. • A relation between size ratio of the binary mixtures and random packing structure. In this work, we studied the influence of powder composition on packing density and other processing-relevant properties of binary mixtures, including powder flowability. Binary mixtures of pharmaceutical powders with different particle size ratios, α and varying fractions of large and small particles were analyzed systematically. Mixtures of three excipients and one API with different composition (2, 5, 10, 30, 50, 70, 90, 95 and 98 wt%) were prepared in a Turbula mixer. Powders with different properties and particle size distribution were chosen, in order to obtain three binary mixtures with different size ratios. Then, macroscopic powder properties including bulk (poured) and tapped density (BD and TD) were measured. A powder rheometer was used to measure the flow function coefficient (ffc), cohesion, compressibility and permeability of the binary mixtures. We considered experimentally three classes of binary mixtures, which are characterized by two critical ratios of particle diameter: the critical size ratio of entrance (α c) and the critical size ratio of replacement (α r), where α c = 0.154 and α r = 0.741. Below the critical size ratio of entrance (α c), the particle asymmetry (ratio between large and small particle diameters) is high and small particles can fill the voids between larger ones. Between α c and the critical size ratio of replacement (α r), the smaller particles are too large to fit in the voids between larger particles (packing structure changes). Above α r , the particles are more or less symmetric in size and overall packing structure does not change by mixing the particles. Our experiments show that there is a non-linear and non-monotonic dependence of all relevant properties on composition for powder mixtures that have an α < α r. This non-linear behavior is even more significant for strongly asymmetric binary mixtures with α < α c. We argue that this behavior is related to the composition dependence of random packing of particulate systems. Our results have relevance to pharmaceutical particle processing operations where constant powder mixture properties are needed to ensure quality standards are met; such operations include capsule or die filling during tableting, and the continuous feeding of powders via screw feeders. Our results suggest that for pharmaceutical particle processing operations, where constant powder mixture properties are a prerequisite for process robustness, the size ratio of API and excipient particles, α should not be smaller than α r = 0.741. [ABSTRACT FROM AUTHOR]

To reduce the reliance on cement clinker, employing ultrafine powders as supplementary cementitious materials (SCMs) is gradually gaining importance. This study investigated the effect of an ultrafine composite powder (UCP) having a specific surface area of approximately 730 m²/kg, produced by industrial ball milling ordinary blast furnace slag and fly ash at a 1:1 ratio, on cement hydration and its durability. The ultrafine composite powder was characterized by X-ray fluorescence spectrometer (XRF), X-Ray diffraction (XRD), particle size analyzer, and scanning electron microscope (SEM). The effects of ultrafine composite powder on the macroscopic properties of cement-based materials were assessed through flowability tests, setting time tests, and mechanical properties tests. Then, the hydration heat release, hydration products and microstructures of the pastes were characterized using isothermal calorimetry, XRD, thermogravimetric (TG), SEM and mercury intrusion porosimetry (MIP). Finally, the effects of ultrafine composite powder on the durability of cement-based materials were evaluated by electrical flux, chloride diffusion coefficient, and mechanical properties tests. The results showed that ultrafine composite powder enhanced the flowability of cement paste under the synergistic effect of superplasticizer. However, the setting time was prolonged due to the dilution of cement by ultrafine composite powder. The ultrafine composite powder significantly improved the early mechanical properties of the mortar, and the mechanical properties after 28-days was equivalent to that of the control. The ultrafine composite powder could significantly decrease the cumulative heat release of cement paste. Due to the high SO 3 content, an additional exothermic peak representing ettringite formation was observed. As the hydration time extends, the hydration products in the paste changed, especially the transformation from ettringite to kuzite, and the formation of hemicarbonate and monocarbonate. As the ultrafine composite powder content increases, the proportion of gel micro-pores increased, whereas the proportion of middle and large capillary pores decreased. Consequently, the total pores in the paste also decreased. The addition of ultrafine composite powder enhanced the durability of the cement-based materials, making it an ideal choice for use in coastal engineering projects. ● UCP was beneficial for enhancing the flowability of cement mortar. ● UCP could enhance the early mechanical properties of cement mortar. ● UCP could make the microstructure of cement paste more compact. ● UCP improved the durability of cement mortar. [ABSTRACT FROM AUTHOR]

• The hydration degrees of cement under the action of SA, VAE, and SB emulsions are 24.87%, 19.57%, and 28.61%, respectively. • Cement hydration products enhance the tensile strength, bond strength and water resistance of coatings. • The interaction mechanism between three polymer emulsions and cement was revealed. In polymer-cement waterproof coating systems, the polymer emulsion influences the hydration behaviour of the cement component, which in turn affects the macroscopic performance of the coating. In this study, the effects of styrene–acrylate (SA), vinyl acetate copolymer emulsion (VAE), and styrene–butadiene (SB) emulsions on the hydration behaviour of cement and macroscopic properties of waterproofing coatings were investigated through chemical binding water testing; thermogravimetric, X-ray diffraction X-ray photoelectron spectroscopy, and Fourier transform infrared microscopic analyses; and macroscopic property characterisation. Moreover, the mechanism of the chemical reaction between the emulsion and cement was clarified. The degree of cement hydration is the least and most affected by the SB and VAE emulsions, respectively. When the cement proportion in the inorganic phase is 50%, the hydration degree of cement in cases involving SA, VAE, and SB emulsions is 24.87%, 19.57%, and 28.61%, respectively. As the cement proportion in the powder phase increases, the tensile strength and bond strength of the polymer cement waterproof coating increase and the elongation at break decreases. The rate of increase of the tensile strength and rate of decrease of the elongation at break both decrease after the cement content becomes 50%. The SA emulsion complexes with the calcium ions in the hydrated environment, which enhances the interfacial bonding between the organic and inorganic phases and results in excellent macroscopic performance of SA waterproof coatings. The SB emulsion waterproof coating has the best mechanical properties and highest water resistance owing to the highest degree of hydration of cement under the action of SB emulsion and hydrophobicity of the emulsion. The VAE emulsion generates hydrophilic polyvinyl-vinyl alcohol and small molecule products that easily dissolve in alkaline hydration environments, leading to low water resistance of the corresponding waterproof coating. [ABSTRACT FROM AUTHOR]

[Display omitted] • A CR/polyurethane modified asphalt sealant was prepared by the in-situ polymerization method. • The high and low temperature rheological properties of sealant were all excellent. • The PU phase was uniformly dispersed in asphalt quantified by fluorescence images. • The sealant has achieved great effects in the treatment of pavement cracks on site. Under the long-term effect of loads and climate conditions, various diseases can appear on the surface of asphalt pavement, causing deterioration in its performance. To address the pavement surface cracks during service, the present study developed a crumb rubber/polyurethane (CR/PU) compound as the modified asphalt sealant with excellent properties. The optimal material proportion, ensuring the best asphalt compatibility was selected to meet the requirements of standard hot-poured sealants for pavement. Additionally, the fineness and content of CR were determined. The research investigated rheological properties, aging performance, microstructure, and modification mechanism of the CR/PU sealant was then applied in an engineering project to evaluate its effectiveness in treating pavement cracks, and suitable construction techniques were summarized. The results revealed that the in-situ polymerization method is an appropriate approach for preparing the CR/PU sealant, demonstrating good high-temperature deformation resistance and low-temperature crack resistance, indicating synergistic interactions between CR and PU. Among various compositions, the sealant with 30 %PU and 15 %CR content exhibited the best thermal oxygen and UV aging properties. Microscopic tests indicated that CR was physically blended with asphalt, while PU underwent chemical modification and formed a cross-linked network structure with asphalt, resulting in CR dispersion around it, enhancing the thermal stability of the system. Furthermore, the test section displayed an ideal crack treatment effect, demonstrating the sealant's excellent sealing, durability, and watertight capacity. [ABSTRACT FROM AUTHOR]

• The effect of nano-ZrO 2 addition on the efficiency of carbonation curing was investigated. • The mechanism of the impact of nano-ZrO 2 in carbonation and sealed curing conditions was compared. • The addition of nano-ZrO 2 in carbonation curing conditions resulted in improved late macroscopic properties. • Adding nano-ZrO 2 can change the microscopic morphology of the matrix and increase the CH reactivity. • Nano-ZrO 2 increased the production of calcium carbonate in carbonation curing conditions. Nanomaterials are characterized by large surface areas and ultrasmall particle sizes, which affect their micromorphologies. In this study, the impact of nano-ZrO 2 on the efficiency of carbonation curing was systematically investigated to compare the mechanism for nano-ZrO 2 in the hydration and carbonation reactions occurring during sealed and carbonation curing and the effects on the micro- and macroscopic properties. The experimental results showed that the hydration rate and degree of carbonation increased gradually with increasing nano-ZrO 2 content. The effect of nano-ZrO 2 on the hydration rate was more significant in the early period (0–72 h); the impact on the carbonation curing efficiency was more significant in the later period (28 days). After 28 days of carbonation curing, the compressive strengths of samples doped with 0.5% and 1% nano-ZrO 2 were higher by 7.5% and 4.9%, respectively, compared to those of the samples without nano-ZrO 2. Moreover, the resistivities of the samples doped with nano-ZrO 2 were higher than that of the control sample (NZ-0%–CC). The efficiency of carbonation curing was mainly attributed to optimization of the substrate micromorphology by the nano-ZrO 2. The addition of nano-ZrO 2 decreased the orientation of the calcium hydroxide (CH) crystals in the mixture and reduced their sizes, leading to an increase in the reactivity of the CH. Moreover, with increases in the amount of nano-ZrO 2 added, the calcium carbonate content of the carbonation product increased slightly. Thus, nano-ZrO 2 improved the efficiency of concrete carbonation curing; high carbonation, high strength and high durability were realized by adding a small amount of nano-ZrO 2 for microscopic morphology optimization. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sulphate attack has a positive effect on GRC when the replacement rate of recycled aggregates is low. • Short periods of immersion in sulfate may improve the mechanical properties of GRC. • The resistance of GRC to sulphate attack is closely related to its structure. • ITZ are less affected by deterioration due to sulfate attack. As a potential alternative to ordinary Portland cement concrete (OPC), geopolymer recycled concrete (GRC) is provided with great research value as it not only significantly reduces carbon dioxide (CO 2) emissions but also promotes the resourceful use of construction and demolition waste (CDW). However, concrete is frequently subjected to extreme circumstances such as sulphate attack during service. To comprehensively explore the structural and performance damage mechanisms of GRC caused by sulphate assault, this study is conducted to erode GRC specimens with recycled aggregate (RA) replacement rate of 0%, 30%, 50%, 70% and 100% by using magnesium sulphate solution with 10% mass fraction. The macroscopic properties of GRC subjected to sulphate attack are examined, including mass loss rate, relative modulus of elasticity and compressive strength. The microstructure and phase evolution of GRC subjected to sulphate attack is analyzed by SEM, EDS and XRD. The micro-mechanical properties of interfacial transition zones (ITZs) in GRC are measured by nanoindentation. The results show that there is no loss of mass in all GRC specimens throughout the erosion age, and the relative dynamic elastic modulus of GRC first increases and then decreases. GRC with 30% RA substitution rate has the best resistance to sulphate attack. The degradation of GRC by sulphate attack is closely related to its internal structural changes. The deterioration of the micromechanical properties of three ITZs by sulphate erosion is not significant, which indicates the RA has favorable performances with geopolymer binder contributing to excellent resistance of GRC to sulfate attack. In addition, a prediction model for the evolution of GRC resistance to sulfate erosion with erosion age for different RA substitution rates is developed, which provides a theoretical guidance for the application of GRC. [ABSTRACT FROM AUTHOR]

Iron tailings have caused serious potential environmental risks with the massive accumulation. This study developed pervious concrete using novel spherical tailings aggregates (STA) synthesized from tailings sand, and explored the mechanism of the effect of STA on macro- and mesoscopic properties. Pervious concrete with natural coarse aggregate and STA replacement up to 100% were prepared. Compressive strength, splitting tensile strength, water permeability and porosity were tested. The thickness and distribution of cement paste at the top, middle and bottom of the specimens were analyzed. The uniformity of the pore distribution was quantified. The economic and environmental benefits are evaluated. The results showed that no more than 50% STA had little effect on the mechanical properties and permeability of the pervious concrete, and high contents of STA led to a decrease in mechanical properties and a significant increase in permeability. The porosity increases with the STA content and linear relations with the mechanical properties and permeability are observed. STA reduced the percentage of paste with thickness below 0.6 mm and increased that above 0.9 mm, and increased the average paste thickness. The aggregate particle interference phenomenon has been proven both theoretically and practically to cause non-uniform distribution of paste and pores, which affects macroscopic properties and water permeability. This study improves the fundamental understanding of the effect of aggregates on the properties of pervious concrete and contributes to the alleviation of environmental stress. [ABSTRACT FROM AUTHOR]

This paper aims to develop a simulation model for heterogeneous traffic using cellular automata (CA). A detailed description of the developed CA model used to simulate heterogeneous traffic is presented. Heterogeneous traffic comprises of vehicles of different static and dynamic characteristics. Therefore, the developed model should be capable enough to include the characteristics of different types of vehicles. The results of simulation depict that not only the model includes heterogeneous traffic characteristics but real traffic behavior is also taken care of. The developed model is calibrated and validated using distance headway–speed relationship obtained from field data. [ABSTRACT FROM AUTHOR]

Characterization of polymers at various structural levels is very important because it aims, inter alia, to improve the properties of materials used on an industrial scale. Research on the structure and morphology of polymers allows for dependence between their macroscopic properties, morphology, and conformations, and for the interactions of polymer chains to be determined. Mechanistic studies examining the creation and interactions of polymer chains are used to plan the synthesis of new polymeric materials. Several analytical methods such as Scanning Transmission Electron Microscopy (STEM) in Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Atomic Force Microscopy (AFM), Fourier Transform Infrared Spectroscopy (FTIR), and Nuclear Magnetic Resonance Spectroscopy (NMR) have been developed to characterize fractography, micro-deformation, nanostructures and self-organization of polymers in detail. In this review, the current status of analytical methods determining details of the structure, morphology and the reorganization of polymeric chains has been summarized. • A new tool "Smart Align" for non-rigid registration of the microscopic data. • The application of AFM-IR in order to reduce the thickness of the sample. • The combination of DNP with solid-state NMR in order to strengthen NMR signals. [ABSTRACT FROM AUTHOR]

Bond relaxation from one equilibrium to another under perturbation matters uniquely the performance of a substance and thus it has enormous impact to materials science and engineering. However, the basic rules for the perturbation-bond-property correlation and efficient probing strategies for high-resolution detection stay yet great challenge. This treatise features recent progress in this regard with focus on the multifield bond oscillation notion and the theory-enabled phonon spectrometrics. From the perspective of Fourier transformation and the Taylor series of the potentials, we correlate the phonon spectral signatures directly to the transition of the characteristic bonds in terms of stiffness (frequency shift), number fraction (integral of the differential spectral peak), structure fluctuation (linewidth), and the macroscopic properties of the substance. A systematic examination of the spectral feature evolution for group IV, III-V, II-VI crystals, layered graphene nanoribbons, black phosphor, (W, Mo)(S 2 , Se 2) flakes, typical nanocrystals, and liquid water and aqueous solutions under perturbation has enabled the ever-unexpected information on the perturbation-bond-property regulations. Consistency between predictions and measurements of the crystal size-resolved phonon frequency shift clarifies that atomic dimer oscillation dictates the vibration modes showing blueshift while the collective vibration of oscillators formed between a certain atom and its nearest neighbors governs the modes of redshift when the sample size is reduced. Theoretical matching to the phonon frequency shift due to atomic undercoordination, mechanical and thermal activation, and aqueous charge injection by solvation has been realized. The reproduction of experimental measurements has turned out quantitative information of bond length, bond energy, single bond force constant, binding energy density, vibration mode activation energy, Debye temperature, elastic modulus, and the number and stiffness transition of bonds from the mode of references to the conditioned upon perturbation. Findings prove not only the essentiality of the multifield lattice oscillating dynamics but also the immense power of the phonon spectrometrics in revealing the bond-phonon-property correlation of solid and liquid substance. Image 1 • Development of regulations for the multifield bond oscillation dynamics and energetics. • Bond vibration frequencies vary with programmed perturbation of the crystal potentials. • Frequency shift correlates the perturbation-relaxation-property of a substance. • Phonon spectrometrics offers ever-unexpected information on the performance of bonds. Atomic undercoordination, charge injection, mechanical and thermal activation mediate material's properties intrinsically by bond relaxation from one equilibrium to another while the phonon spectrometrics probes the ever-unexpected information of the binding energy density, atomic cohesive energy, single bond force constant, crystal elastic modulus, Debye temperature and the abundance-length-stiffness transition of bonds under perturbation Key Points treated as abstract teaser kindly check and correct if necessary.-->. [ABSTRACT FROM AUTHOR]

Abstract Composites were prepared from three traditional microfillers, glass beads (GB), wood flour (WF) and glass fibers (GF), as well as sodium montmorillonite (NaMMT) and an organophilic clay (OMMT) in a polyamide (PA) matrix in order to compare their properties and discuss the benefits and drawbacks of using micro- or nanofillers. Structure was characterized by various techniques, interaction estimated by two approaches and local deformation processes were followed by acoustic emission testing and volume strain measurements. The results showed that properties can be modified in a relatively wide range. True reinforcement can be achieved with glass fibers, but the influence of all traditional fillers can be predicted with good certainty because their structure can be controlled quite well. Although the layered silicates reinforce polyamide even better than glass fiber, improvement is achieved only in a very narrow composition range because the structure of their composites cannot be controlled to the desired extent. Numerous local processes take place during the deformation of PA composites, such as cavitation and shear yielding in the matrix, as well as particle related processes. However, it is matrix deformation rather than particle processes that determines composite properties. Highlights • The influence of all traditional fillers can be predicted with large certainty because their structure can be controlled. • Layered silicates reinforce polyamide even better than glass fiber but only in a very narrow composition range. • Structure of layered silicate polyamide composites cannot be controlled in the desired extent. • Numerous local deformation processes take place during the deformation of PA composites. • The properties of PA composites are not determined by these latter, but by those taking place in the matrix. [ABSTRACT FROM AUTHOR]

[Display omitted] • The effects of CO 2 concentration and reaction time on the microstructure are mainly due to changes in pore structure. • There is a critical value for both the reaction time and the effect of carbon dioxide concentration on the pore structure. • L c is the best index to reflect the highest temperature experienced by coke in blast furnace. • When the surface concentration reaches the critical value (10%), carbon dioxide reacts with the inner coke through pores and cracks, resulting in larger pores inside the coke. • The macroscopic properties of coke (compressive strength and reactivity after reaction) are influenced by both pore structure and microstructural properties. To address the deterioration of coke properties and subsequent fines caused by coke gasification reaction inside blast furnaces, orthogonal gasification tests were conducted on industrial coke simulating a blast furnace environment, and the effects of reaction temperature, carbon dioxide concentration, and reaction time on the pore structure, microstructure, and macroscopic properties of coke were analyzed. An increase in the reaction temperature led to the reaction of carbon dioxide with the internal coke through the pores and cracks, and a critical value was observed for both the reaction time and CO 2 concentration on the pore structure. Temperature had a significant effect on the degree of graphitization and graphitization defects, whereas the effects of CO 2 concentration and reaction time on the microstructure were mainly due to changes in the pore structure. The macroscopic properties of coke (compressive strength and reactivity) were influenced by both its pore structure and microstructure. As the reaction temperature and time increased, the compressive strength of the coke increased initially and then decreased. [ABSTRACT FROM AUTHOR]

Frequent mining stress disturbances in deep-earth resource extraction lead to different degrees of initial damage within cemented tailings backfill (CTB), which in turn changes the structural characteristics of the matrix and significantly affects the stability of CTB. To simulate the stress disturbance process of CTB during mining activities more realistically, cyclic loading and unloading disturbances were performed on the CTB. The stress disturbance levels (SDL) were 20, 40, 60, and 80% uniaxial compressive strength (UCS), and the stress disturbance counts (SDC) were 5, 10, 15, and 20 times, respectively. Subsequently, a series of experimental studies were conducted on CTB and disturbed damage CTB (DCTB) using UCS, nuclear magnetic resonance, ultrasonic pulse velocity (UPV) testing, and acoustic emission (AE) monitoring. The results show that the UCS of the backfill decreased with increasing SDL and SDC, except for 20% SDL and 5th SDC. The elastic modulus exhibited a rise at 20%–40% SDL and a fall at 60%–80% SDL. Compared with CTB, the stress–strain curve of DCTB showed a left shift - overlap - right shift - accelerated right shift change in the compacting stage with increasing SDL. Moreover, the porosity and UPV reflected by the mesoscopic structure correspond to the trend of UCS. The correlation mechanism between mesoscopic structure and macroscopic strength was determined, and the initial damage degree of DCTB was defined in terms of the average variation characteristics of macro-mesoscopic parameters. According to the AE monitoring results, it was observed that increasing SDL and SDC led to a significant increase in the AE energy active stage during loading. The damage curve established from the AE energy considering the initial damage degree rose exponentially. As the initial damage degree intensified, a noticeable and wide-range drop in the b -value before the peak was observed, indicating the occurrence of frequent large-scale fracture activities within the DCTB. Also, the damage degree of DCTB intensified, the collapse zone increased, and the failure mode of the backfill transformed from tensile to mixed tensile-shear damage. The research results can provide theoretical support and a reference basis for the stability analysis and strength design of the backfill under the action of mining stress. [ABSTRACT FROM AUTHOR]

It is well established that the microstructure has significant effects on the properties of axial braided C/C composites. In this study, a method coupling the homogenization method and finite element method (FEM) was proposed to predict the relationship between the microstructure characteristics and macroscopic properties. Based on the representative volume element (RVE) model, the periodic displacement boundary condition was introduced to predict the equivalent elastic properties of the RVE and component of C/C composite material, and the coefficient of thermal expansion (CTE) of the material was predicted by the energy prediction method. The predicted results were in good agreement with experimental results. By predicting the thermal and mechanical properties of the materials with different braiding spacing and fiber rod diameter, the variation of the properties with braiding spacing and fiber rod diameter was obtained. The research methods and results in this paper could provide important references for the optimization and rational application of composite materials.

ABSTRACT: The modification of epoxy composites through the construction of nanostructures via the self‐organization of block copolymers in epoxy has become a hot topic. In this research, polystyrene‐b‐poly(ɛ‐caprolactone)‐b‐polydimethylsiloxane‐b‐poly(ɛ‐caprolactone)‐b‐polystyrene (PS‐PCL‐PDMS‐PCL‐PS) block copolymers with different lengths of PS subchains were synthesized and incorporated into epoxy thermoset. Due to the difference in the length of PS subchains, two different sizes of core‐shell nanostructures were obtained. When these two block copolymers were incorporated into epoxy, the tensile strength, elongation at break, damping temperature in range (tan δ > 0.2), and storage modulus of the epoxy thermoset below 105 °C were simultaneously improved. Meanwhile, the effects of the lengths of PS subchains on the size of nanostructures and the relationship between microstructure and macroscopic properties of epoxy composites were systematically investigated. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46362. [ABSTRACT FROM AUTHOR]

This study applied a type of fly ash microsphere (FAM) collected directly from a high-temperature furnace using ceramic dust tubes to high-strength concrete, and with silica fume as a control admixture, investigated the effects of FAM on the hydration and hardening processes of the cementitious materials and the macroscopic properties of the high-strength concrete. Two cement replacement levels (8% and 15%) and two water-to-binder (W/B) ratios (0.35 and 0.25) were utilized. The results show that FAM has a relatively high level of early activity; SEM images indicate that a significant portion of the FAM reacted at early ages in the cement-FAM hardened paste. Though the early activity of FAM is lower than that of silica fume, the cement-FAM complex binder has similar hydration properties with the cement-silica fume complex binder. At 90 d, FAM consumed less Ca(OH) 2 than silica fume and a significant amount of unreacted FAM remained in the hardened pastes. The contributions of FAM to the pore structure of the hardened pastes are lower than those of silica fume at early ages; however, FAM can significantly improve pore structure at late ages, similar to silica fume. In addition, FAM can improve the flowability, late-age strength, and permeability to chloride ions of concrete, while decreasing early-age autogenous shrinkage. [ABSTRACT FROM AUTHOR]

• The impact of high beta irradiation doses on the structure and macroscopic properties of the ISG glass has been studied. • The modifications induced by beta decays on the structure and macroscopic properties of ISG glass are similar to those induced by a recoil nucleus (of the alpha decays) but of weaker intensity. • The use of double external irradiation enables to simulate the impact of both beta decays and recoil nuclei of alpha decay. • There is no sequential coupling or synergistic effect of electron irradiation and nuclear collisions induced by heavy ion irradiation on the glass damaged state. This study addresses the consequences of three irradiation scenarios on the structure and macroscopic properties of the ISG glass. The coupling effect between 2.5 MeV electron irradiation (simulating the effects of beta particles and gamma rays) and 7 MeV Au irradiation (simulating the nuclear collisions of the recoil nuclei of alpha decays) was studied by comparing two monobeam irradiations with a sequential double beam irradiation. Various experimental techniques were used to characterize the glass structure and properties, combining Raman, NMR, IR-ATR spectroscopies, hydrostatic weighing, He pycnometry, X-Ray Reflectivity, AFM, surface tension and Vickers microhardness measurements. Electron irradiation up to 3.25 GGy induces only small changes of ISG glass structure and macroscopic properties than Au irradiation. Moreover, the magnitude of the changes induced by the sequential irradiation scenario, i.e. electron followed by Au ions, are the same as the one induced by the monobeam irradiation by Au ions, except for the surface tension. Because the bulk damage state are similar, this work demonstrates that there is no coupling between the damage generated by the electron irradiation and the subsequent nuclear collision generated by Au ions. Finally, the hardness and density changes of ISG glass are very similar to those of SON68 glass when submitted to similar irradiation conditions by electron or nuclear collisions. Therefore ISG glass is found to be a good glass surrogate with respect to radiation ageing of the SON68 glass. [ABSTRACT FROM AUTHOR]

We review the impact of tetrahedral order on the macroscopic dynamics of bent-core liquid crystals. We discuss tetrahedral order comparing with other types of orientational order, like nematic, polar nematic, polar smectic, and active polar order. In particular, we present hydrodynamic equations for phases, where only tetrahedral order exists or tetrahedral order is combined with nematic order. Among the latter, we discriminate between three cases, where the nematic director (a) orients along a fourfold, (b) along a threefold symmetry axis of the tetrahedral structure, or (c) is homogeneously uncorrelated with the tetrahedron. For the optically isotropic T phase, which only has tetrahedral order, we focus on the coupling of flow with, e.g., temperature gradients and on the specific orientation behavior in external electric fields. For the transition to the nematic phase, electric fields lead to a temperature shift that is linear in the field strength. Electric fields induce nematic order, again linear in the field strength. If strong enough, electric fields can change the tetrahedral structure and symmetry leading to a polar phase. We briefly deal with the T phase that arises when tetrahedral order occurs in a system of chiral molecules. To case (a), defined above, belong (i) the non-polar, achiral, optically uniaxial D2d phase with ambidextrous helicity (due to a linear gradient free energy contribution) and with orientational frustration in external fields, (ii) the non-polar tetragonal S4 phase, (iii) the non-polar, orthorhombic D2 phase that is structurally chiral featuring ambidextrous chirality, (iv) the polar orthorhombic C2v phase, and (v) the polar, structurally chiral, monoclinic C2 phase. Case (b) results in a trigonal C3v phase that behaves like a biaxial polar nematic phase. An example for case (c) is a splay bend phase, where the ground state is inhomogeneous due to a linear gradient free energy contribution. Finally, we discuss some experiments that show typical effects related to the existence of tetrahedral order. A summary and perspective is given. [ABSTRACT FROM AUTHOR]

Purpose: To determine the effect of relative humidity (RH) and hydroxypropyl methylcellulose (HPMC) on the physico-mechanical properties of coprocessed MacroceLac 100 using 'DM' approach. Methods: Effects of RH and 5% w/w HPMC on MacroceLac 100 Compressibility Index (CI) and tablet mechanical strength (TMS) were evaluated by 'DM'. The 'DM' approach evaluates material properties by combining 'design of experiments', material's 'macroscopic' properties, 'molecular' properties, and 'multivariate analysis' tools. A 4X4 full-factorial experimental design was used to study the relationship of MacroceLac 100 molecular properties (moisture content, dehydration, crystallization, fusion enthalpy, and moisture uptake) and macroscopic particle size and shape on CI and TMS. A physical binary mixture (PBM) of similar composition to MacroceLac 100 was also evaluated. Multivariate analysis of variance (MANOVA), principle component analysis, and partial least squares (PLS) were used to analyze the data. Results: MANOVA CI ranking was: PBM-HPMC > PBM > MicroceLac100 > MicroceLac100-HPMC ( p < 0.0001). MANOVA showed PBM's and PBM-HPMC's TMS values were lower than MicroceLac100 and MicroceLac100-HPMC ( p < 0.0001). PLS showed that % RH, HPMC, and several molecular properties significantly affected CI and TMS. Conclusions: Significant MicroceLac100 changes occurred with % RH exposure affecting performance attributes. HPMC physical addition did not prevent molecular or macroscopic matrix changes. [ABSTRACT FROM AUTHOR]

Foods are partially crystalline partially amorphous systems. Edible films are considered good models for food systems due to their interesting physical properties, quite straightforward matrices, and easy reproduction. Chitosan is a semicrystalline biopolymer, biocompatible, biodegradable, with antimicrobial activity and filmogenic properties, thoroughly used in edible films' studies. This work aims to investigate the relationship between chitosan films' molecular relaxation time, their microstructure (crystallinity) and functional properties. Analyses were carried out using data on chitosan/glycerol films prepared with different polymer/plasticisant concentrations. Results demonstrate that there is a relationship between macroscopic properties and water and glycerol relaxation times. Moreover, results show that while water is free in the matrix, glycerol is linked to the chitosan polymeric chains, decreasing intermolecular attractions and increasing free volume, thus facilitating molecular migration. Also the data analysis reveals the usefulness of NMR and molecular mobility studies in the matrix for characterisation and development of polymeric structures. Industrial relevance NMR spectroscopy is currently one of the key methods for food characterisation. Foodstuff is a complex matrix including many different compounds with different chemical structures, concentrations, solubility, properties and nutritional values. From a fundamental perspective, foods are mainly edible and digestible biopolymers that are partially crystalline/partially amorphous and thus edible films, specifically chitosan/glycerol films can be very interesting food model systems for mobility and microstructure studies. Studies on water and solids' mobility and thermo-mechanical properties in food systems (real or model systems) are fundamental to fully attain food physical properties and stability. These studies may be extremely useful for food product and process design, safety and sensorial attributes and also for better understanding and predicting, for example, food storage stability conditions. [ABSTRACT FROM AUTHOR]

• Proper application of MEA requires coordinating the relationship between expansion stress and the resistance response of the cement matrix. • Fly ash stabilizes the positive effect of MEA on increasing microstructure compactness. • The reduction in alkalinity results in a more uniform distribution of Mg(OH) 2 without concentrated expansion. The application of MgO expansive additive (MEA) in cement-based materials is one of the effective measures to compensate for shrinkage. However, related to the delayed excessive expansion, the incorporation of MEA has a potential risk of crack formation and decline of mechanical properties. To address the latter issue, an innovative approach using a large amount of fly ash with pozzolanic activity to coordinate the expansion stress of MEA and the resistance response of cement matrix is proposed in this paper. The effects of fly ash on MgO-based shrinkage-compensating cement are systematically investigated from the aspects of macroscopic properties and microstructural characteristics. The addition of 20% fly ash magnifies the effect of MEA compensation for early shrinkage and inhibits the later excessive volume expansion. In this way, the problem of mechanical properties decrease has been well resolved, and compared with 28 days, the compressive and flexural strengths with 20% fly ash at 90 days are increased by 23.3% and 18.4%, respectively. XRD and TG/DSC confirm fly ash slows down the early hydration process of MgO-based shrinkage-compensating cement and forms a stronger cement matrix through secondary reaction to offset the later reduced delayed expansion of MEA. NAD demonstrates fly ash stabilizes the positive effect of MEA on increasing microstructure compactness through expansion. SEM and EDS illustrate fly ash improves distribution of Mg(OH) 2 , avoiding the deterioration of microstructure caused by local excessive expansion. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel thermosetting polyurethane asphalt binder with great mechanical performance was prepared. • Analyzing effects of impact factor on the curing kinetics parameters of polyurethane asphalt binder. • The correlation coefficients between micro-parameters and macroscopic performances of PAB were established. • Verifying the effects of polyurethane dosage on the elastic recovery performance of PAB. Recently, novel thermosetting polyurethane asphalt binder (PAB) has been studied by more researchers. This paper investigated the curing mechanism, microstructure and macroscopic performance of PAB. The mechanical properties, rheological properties, and elastic recovery performance of PAB were evaluated. Fourier transform infrared spectroscopy (FTIR), fluorescence microscopy (FM) and gel permeation chromatography (GPC) were adopted to confirm the chemical reaction and microstructure, curing process was studied combined with kinetics. Results showed PAB was the first-order curing reaction system and slow curing progress was conducive to mixing application, polyurethane particles changed from granular to the reticular structure during curing. The ratio of large molecular weight showed an increasing trend as temperature/time up. Furthermore, multi-stress creep recovery demonstrated that elastic recovery performance of PAB-50 (0.1 kPa) can be improved to 2.2 times, 8.1 times approximately compared with styrene–butadienestyrene block copolymer asphalt binder (SBSMA) and unmodified asphalt binder (MA). The tensile strength of PAB-30 (cured at 4d-130 °C) was 3.1 times that of 2 h (130 °C). Viscosity temperature index (VTS) value gradually increased implied that temperature sensitivity was habited by curing time. Pearson correlation coefficient illustrated that the mechanical property of PAB was positively related to the large molecular weight and conversion rate of the isocyanate group. The non-recoverable creep compliance reduction positively relied on polyurethane content and microstructure. [ABSTRACT FROM AUTHOR]

Rational approach towards the QSAR/QSPR modeling requires the descriptors to be computationally efficient, yet physically and chemically meaningful. On the basis of existing simplex representation of molecular structure (SiRMS) the novel 'quasi-mixture' descriptors were developed in order to accomplish the goal of characterization molecules on 2D level (i.e. without explicit generation of 3D structure and exhaustive conformational search) with account for potential intermolecular interactions. The critical properties of organic compounds were chosen as target properties for the estimation of descriptors' efficacy because of their well-known physical nature, rigorously estimated experimental errors and large quantity of experimental data. Among described properties are critical temperature, pressure and volume. Obtained models have high statistical characteristics, therefore showing the efficacy of suggested 'quasi-mixture' approach. Moreover, 'quasi-mixture' approach, as a branch of the SiRMS, allows to interpret results in terms of simple basic molecular properties. The obtained picture of influences corresponds to the accepted theoretical views. [ABSTRACT FROM AUTHOR]