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Large scale synthesis of high-efficiency bifunctional electrocatalyst based on cost-effective and earth-abundant transition metal for overall water splitting in the alkaline environment is indispensable for renewable energy conversion. In this regard, meticulous design of active sites and probing their catalytic mechanism on both cathode and anode with different reaction environment at molecular-scale are vitally necessary. Herein, a coordination environment inheriting strategy is presented for designing low-coordination Ni2+ octahedra (L-Ni-8) atomic interface at a high concentration (4.6 at.%). Advanced spectroscopic techniques and theoretical calculations reveal that the self-matching electron delocalization and localization state at L-Ni-8 atomic interface enable an ideal reaction environment at both cathode and anode. To improve the efficiency of using the self-modification reaction environment at L-Ni-8, all of the structural features, including high atom economy, mass transfer, and electron transfer, are integrated together from atomic-scale to macro-scale. At high current density of 500 mA/cm2, the samples synthesized at gram-scale can deliver low hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) overpotentials of 262 and 348 mV, respectively.

Tin sulfide (SnS) is an attractive anode material for energy storage, but suffers from poor reversibility and serious polarization. In this work, to increase electron and ion transportation and the structural stability of SnS, polypyrrole–phosphomolybdic acid-coated SnO2@C spheres were used as self-templates to construct SnS@C nanospheres coated with MoS2 nanosheets and a nitrogen, phosphorus-codoped carbon layer (SnS@C/MoS2@N,P-C). Endowed with a synergetic effect from SnS, MoS2, and the carbon network, SnS@C/MoS2@N,P-C delivered a first reversible capacity of 628 mA h g−1 with a high initial coulombic efficiency of 74.9%, capacity retention of 59.8% over 2000 cycles at 5.0 A g−1 and an exceptional rate capability of 250 mA h g−1 at 10.0 A g−1 when used as an anode material for sodium-ion batteries (SIBs). This high rate capability is possibly promoted by pseudocapacitive behavior attributed to the rich interfaces between the different components. Moreover, an assembled full cell with Na3V2(PO4)3@C as the cathode exhibits a capacity of 455 mA h g−1 at 0.5 A g−1 after 50 cycles, showing good potential for practical applications in the future.

High-viscosity modified asphalt (T-HVA) specifically used for drainage/permeable asphalt pavement was prepared by composite modification of matrix asphalt using a thermoplastic elastomer (TPE) and SBS particles. The performance of the high-viscosity modified asphalt (T-HVA) was characterized by conventional tests, and compared with the performance of 70# asphalt, SBS modified asphalt and engineering high-viscosity asphalt. The results show that all the indicators of the modified asphalt are better than that of the matrix asphalt, and the dynamic viscosity of the T-HVA is greater than one million Pa.s, which is much higher than that of the engineering high-viscosity asphalt and SBS modified asphalt. The segregation test shows that the compatibility and stability of T-HVA asphalt are better than others. Cohesion test shows that the cohesion of the modified asphalt is obviously better than that of the matrix asphalt at different temperatures, and the higher the temperature, the better the cohesion, and the cohesion of the T-HVA before and after aging is relatively stable. The result of the peeling rate measured by ultraviolet spectrophotometry shows that: the peeling rate of the T-HVA is the smallest, i.e., the adhesion is the best, and is consistent with the dynamic viscosity, i.e., the greater the dynamic viscosity, the better the adhesion. Based on the comprehensive analysis of various indicators. The results of Performance Grade (PG) grading test show that T-HVA has good high and low temperature performance. The modified materials with good dispersion in asphalt and the TPE particles as high elastic interlocking units are uniformly distributed in the network structure; The T-HVA has relatively strong aggregate adhesion and cohesiveness, exhibits good high temperature stability and low temperature flexibility, and is suitable for drainage/permeable asphalt pavement. Keywords: Pavement engineering, High-viscosity modified asphalt, Cohesion and adhesion, Permeable asphalt pavement

Multiple-metal compound materials have been demonstrated as high performance anode materials for energy storage. In this work, porous hollow polyhedron structured multicomponent sulfides and N -doped carbon-based composite (MnS-(ZnCo)S/N-C) is prepared through a gas-solid reaction using Mn, Zn, Co-based ternary metal−organic frameworks as precursor. As sodium ion batteries anode, MnS-(ZnCo)S/N-C exhibits impressive electrochemical performance, especially for the cycling performance at high current. At a current density of 2.0 A g −1, it delivers a capacity of 316 mAh g−1 within 400 cycles and a high capacity retention (92.9%) compared with that of the third cycle. Furthermore, the composite electrode maintains a capacity retention of 40% when the current raises from 0.1 to 10.0 A g−1 step by step. As a robust sodium storage host, this composite anode benefits from porous hollow polyhedron structures composed of primary nanoparticles, N doped C coating on primary particles, and multicomponent sulfides.

The internal drainage of roads is one of the most important measures to prevent water accumulation, especially on rainy days. Porous cement stabilized macadam is widely used as a skeleton porous material because of its excellent performance in road bases. So far, many scholars have researched the design and pavement performance of Porous cement stabilized macadam. However, minimal research has focused on the permeability and mechanical properties of Porous cement stabilized macadam materials subjected to freeze - thawing cycles in freezing areas. In this paper, through an indoor equivalent freeze–thawing cycle test, the effect of freezing and thawing cycles on the permeability performance and mechanical properties of two test groups was studied: a wet-frozen freeze–thawing test group and a water-immersion-frozen freeze–thawing test group. The changes in the void ratio, unconfined compressive strength, indirect tension strength, and compressive modulus of the resilience after repeated freeze–thawing cycles were examined. And the effects of the freeze–thawing cycles on permeability performance and mechanical properties under different conditions were evaluated. The experiment identified a minimal freeze–thawing cycle effect on the permeability performance of the porous cement stabilized macadam materials, for which the maximum increase in void ratio did not exceed 1.3%. However, it was bring the greater impact on the mechanical properties of the porous cement stabilized macadam after freeze–thawing cycle test. Unconfined compressive strength and indirect tension strength were reduced by a maximum of 37.94% and 53.49%, respectively, and the freeze–thawing cycle under saturated water conditions exhibited the greatest influence on the properties of the porous cement stabilized macadam as well as the unconfined compressive strength of the sample subjected to the water-immersion-frozen freeze–thawing test groups and wet-frozen freeze–thawing test groups. The unconfined compressive strength of the specimen was reduced by a maximum of 15.09%, whereas the indirect tension strength was relatively decreased by 28.57%. In addition, according to the test data to fit the corresponding function equations, it is proposed targeted improvement measures to provide theoretical guidance for practical engineering applications.

The exploration of low-cost, stable, and highly active noble-metal-free electrocatalyst for hydrogen evolution reaction (HER) in a wide pH range is crucial but still challenging task for renewable energy techniques. MoS2-based materials have been considered as a promising electrocatalyst for HER. However, corresponding studies have been hampered by the lack of effective routes to fully utilize the large number of inert basal plane for catalyzing HER, especially under alkaline media. Herein, a novel ammonia ions-guided-nitrogenization-phosphorization strategy is developed to prepare N and P co-doped MoS2 with active basal plane for efficient catalyzing HER with a quite low overpotential of 116 and 78 mV in 0.5 M H2SO4 and 1.0 M KOH to achieve a current density of 10 mA cm−2, respectively. Experimental studies and theoretical calculations confirm Mo-N-P sites in the basal plane of MoS2 can not only accelerate HER kinetics, but also result in energetic favorability and structure stability. Furthermore, outstanding performances are also obtained under both sea and river water, vastly broadening the application prospects.

Anode materials are demonstrated to essentially affect the electrochemical performance of sodium-ion batteries (SIBs), which are considered as a promising large-scale energy storage device. In this work, alloying ZnSxSe1-x (x = 0.24) and N doped carbon composite (ZnSxSe1-x/N-C (x = 0.24)) hierarchical nanospheres are prepared by selenizing the ZnS precursor. The corresponding X-ray diffraction and high-resolution transmission electron microscopy results prove the formation of an alloyed phase, resulting in a wider lattice compared with ZnS. Benefitting from the coexistence of S2− and Se2− in the ZnSxSe1-x lattice, the weaker Zn-Se bonds and wider lattice spacing facilitate ultrafast pseudocapacitive sodium storage capability and enhanced cycling stability, when ZnSxSe1-x/N-C is used as anode material for SIBs. At current of 1.0 A g−1, it delivers a capacity of 378 mAh g−1 after 130 cycles with capacity retention of 87.9%, which is much higher than 34.3% for the ZnS/N-C electrode. In addition, for the rate performance, it can maintain an impressive capacity of 233 mAh g−1 at 10.0 A g−1 with a capacity retention of 55.9% in comparison with the capacity at 0.2 A g−1. This work provides us common thoughts to enhance the electrochemical performance of transition metal chalcogenide anode through anion substitution.

Sodium ion batteries (SIBs) have been widely considered as a competitive alternative to construct low-cost and large-scale energy storage system. Unfortunately, low energy density and poor cycle life are main issues that need prompt solutions. Herein, an effective and controllable strategy, using metal–organic framework (MOF) precursors, was utilized to fabricate in situ N-doped carbon modified bimetallic sulfide hollow spheres with different metal ratios. When used as the anode material for SIBs, (Co0.5Ni0.5)9S8 solid-solution combined with in situ N-doped carbon ((Co0.5Ni0.5)9S8/N–C) is demonstrated to balance several aspects to deliver a superior electrochemical performance. (Co0.5Ni0.5)9S8/N–C exhibits the high specific capacity of 723.7 mA h g−1 at the 100th cycle at the current of 1.0 A g−1 and a high rate performance with the capacity of 569.1 mA h g−1 at 10 A g−1, yielding the high capacity retention of 60.2% compared with the capacity of 0.1 A g−1 (945.1 mA h g−1). The fast sodium storage capability is promoted by the capacitive contribution. Meanwhile, ex situ XRD is used to study the phase transition of the solid solution anode during the Na-storage process. The excellent performance can be attributed to the incorporation of Ni into the Co9S8 phase, in situ N–C coating and a stable hollow structure.

The exploration of highly active and stable noble-metal-free electrocatalysts for hydrogen and oxygen evolution reaction is a challenging task to achieve sustainable production of H2 through water splitting. Herein, we present the design and synthesis of a novel three-dimensional(3D)-networked heterogeneous nickel phosphide/sulfide electrocatalyst consisting of Ni2P strongly coupled with Ni3S2 in situ grown on Ni foam. Benefiting from the strong interfacial coupling effects between Ni2P and Ni3S2, large surface area, highly conductive Ni foam support, and the unique 3D open configuration, the optimal 3D-networked hybrid electrode exhibits superior electrocatalytic activity with extremely low overpotentials of 80 and 210 mV to deliver a current density of 10 mA cm−2 for HER and OER in 1.0 M KOH, respectively. Assembled as an electrolyzer for overall water splitting, this electrode delivers an impressive low onset potential of only 1.45 V and gives a current density of 10 mA cm−2 at a very low cell voltage of 1.50 V, which is dramatically superior to the current state-of-the-art electrocatalysts. In combination with density functional theory (DFT) calculations, this study demonstrates that the strong coupling interactions between Ni2P and Ni3S2 synergistically optimize the electronic structure and tune the hydrogen (or water) adsorption energy, thus significantly enhancing the overall electrochemical water-splitting activity. Our work might shed some new lights on the design and fabrication of efficient and robust three-dimensional hybrid electrode materials for a variety of electrochemical applications.

As anode materials, the electrochemical performance of layered transition metal dichalcogenides (TMDs), can be improved with surface layer protection. In this study, flower-like MoSe2 nanostructures are easily obtained from a solvothermal reaction followed by an annealed process in inert atmosphere. Then the MoSe2 nanostructures are further treated in air at 350 °C, and amorphous MoO3 can be formed on MoSe2 surfaces, resulting into MoSe2/MoO3 heterogeneous nanostructures. The MoSe2/MoO3 composite, as anode materials for sodium ion batteries (SIBs), shows better performance than those of pristine MoSe2, which includes charge/discharge capacity, cycling stability and rate capability. At low current of 50 mA g−1, the discharge capacity can reach as high as 729 mAh g−1. In addition, even at high current of 10 A g−1, the discharge capacity maintains at 314 mAh g−1. At high currents of 1000 and 2000 mA g−1, after 200 cycles, the capacity retention can be kept at 101.9% and 99.5%, respectively. The enhanced performance of MoSe2/MoO3 heterogeneous nanostructures can be attributed to the amorphous MoO3 surface layer, which prevents selenium dissolution and subsequently improves the cycle performance and increases sodiation/desodiation kinetics because of the amorphous nature.

Sodium-ion batteries (SIBs) are considered as a promising energy storage device, and anode materials are proved to essentially affect their electrochemical performance. In this work, a yolk–shell structured Co9S8/MoS2 polyhedron with N-doped carbon composite (Co9S8/MoS2–CN) was designed and synthesized through a step by step process using ZIF-67 as the precursor. And this composite is demonstrated to be an excellent electrode candidate material for SIBs due to the magnificent yolk–shelled structures, in situ CN coating and the synergistic effect of the binary sulfides. The Co9S8/MoS2–CN composite electrode shows highly stable cycling performance and delivers a reversible discharge capacity of 438 mA h g−1 within 150 cycles at a current density of 1.0 A g−1, which is much higher than that of Co9S8–CN or MoS2 electrodes. Even at a high current density of 2.0 A g−1, it can also deliver an impressively stable capacity of 421 mA h g−1 within 250 cycles.

The use of nano-SiO2 in concrete has attracted intense attention recently due to its notable improvement in mechanical properties as well as consumption of industrial by-product to enhance the life cycle sustainability. However, the effect of nano-SiO2 on the air pore structure and properties of air entrained cement-based materials is almost not involved in former studies. In this paper, the influence of nano-SiO2 hydrosol (NSH) on the air pore structure, strength and frost resistance of air-entrained mortar was reported. Two typical air entrained agents (AEAs) were utilized to prepare air-entrained mortar with the targeted air content of fresh mortar at the same level. The effects of the addition of NSH on air pore structure, hydration heat release and frost resistance of air-entrained mortar were investigated. Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray Spectroscopy (EDS) were used to analyze the mechanism of NSH on entrained air bubbles and pores. Results suggest that the incorporation of NSH can affect entrained air bubble behavior, influence the pore size distribution and densify the hydration products of the air pore wall, thereby effecting the mechanical properties and frost resistance of air-entrained mortar. SEM and EDS data proved differences in chemical composition of air bubble shell entrained by two types of AEAs. The differences resulted in diverse degree of NSH affected air-entrained mortar performance. Due to the effect of early accelerated heat release of cement on the stability bubbles and excessive mortar consistency on the retention of coarse air bubble, it is not recommended to add too much NSH in order to optimize the air pore structure and frost resistance of air-entrained mortar. This study deepens our understanding into the fundamental mechanism of NSH in air-entrained mortar, which also prompts its application to create a sustainable built environment.

To develop a new type of modified asphalt, castor oil-contained asphalt is obtained with green renewable castor oil instead of petroleum-based polyols. The second monomer-liquefied methylene diphenyl diisocyanate (MDI) is gradually added to a pitch system with shearing, and castor oil-based polyurethane (PU)-modified asphalt is prepared. The dosages of castor oil and second monomer MDI are calculated with isocyanate index R (—NCO/—OH)=1.8, and the modified asphalt with 10%-30% content of castor oil-based PU is synthesized. The performance of the modified asphalt is characterized through a conventional experiment. Experiment results show that the modifier in the asphalt is dispersed evenly, and the high-and low-temperature performance of the castor oil-based PU-modified asphalt is improved. The high-temperature grade of the asphalt is determined by performing the original grade test and thin film oven test on samples. On the basis of the high-temperature grade, the high-temperature performance of different asphalt samples after aging is analyzed and evaluated via a multiple stress creep recovery test. Test results show that the creep compliance of the modified asphalt is reduced significantly, and the recovery rate is increased compared with that of base asphalt. Increased elasticity and stiffening are achieved. With the increase in modifier dosage, creep compliance declines and the recovery rate increases simultaneously. The modification effect is also improved.

The fundamental material for production of high-modulus asphalt (HMAC) is high modulus asphalt binder (HMAB), which is normally manufactured from hard-grade asphalt, rock asphalt modification, and polyolefin modification. This paper investigated rheological properties and performance of HMAB as compared to Styrene-Butadiene-Styrene (SBS) modified binder and neat binder using comprehensive laboratory performance tests. Specifically, the performance of HMAB modified with two different high modulus additives, rock asphalt (RA) and polyolefin (PR), were compared. The performance indicators include linear viscoelasticity characterized by temperature sweep and frequency sweep tests, rutting resistance by multiple-stress creep recovery (MSCR) test, and fatigue resistance by linear amplitude sweep (LAS) test. The effects of high-modulus modifier on master curve of dynamic shear modulus of HMAB were found identical. The temperature dependencies of asphalt binder were found to be significantly dependent on the material source of neat binder. However, the rutting resistance of HMAB modified by rock asphalt and polyolefin is better than that of SBS modified binder and neat binder. The polyolefin modified HMAB showed better rutting resistance than rock asphalt modified HMAB; while the comparison results was opposite for fatigue resistance. The simplified viscoelastic continuum damage (S-VECD) theory was employed to interpret the LAS test results for fatigue life prediction of asphalt binder. The SBS binder showed the best fatigue performance followed by HMAB and neat binder.

Cement concrete is an extensively used construction material in buildings and civil infrastructures. As infrastructure moves into plateau areas, freeze-thaw failure is a main durability challenge for concrete due to the frequent freeze-thaw cycles and entrained air pore coarsening in high altitude and low air pressure (Lap). Recently, there has been a growing interest in the application of nano-silica (NS) due to its notable improvement in concrete durability in plateau areas as well as the consumption of industrial by-product, both improve the sustainability of civil infrastructures. Therefore, this paper studies the mechanism of NS for enhancing the robustness and durability of concrete in low air pressure, the results of which foster the application of NS concrete for designing and constructing sustainable civil infrastructures in plateau areas. Two different kinds of air-entraining agents (AEAs) were utilized to prepare air-entrained concrete. Following this, NS was employed to modify the micro and meso structure of the concrete, and then determine their influence on the performance of concrete. The influence of NS on the entrained air bubbles and air pores were analyzed via micro measurements including Fourier Transform infrared spectroscopy (FTIR), Energy-Dispersive X-ray Spectroscopy (EDS), and Scanning Electron Microscope (SEM). CABR-457 hardened concrete air pore structure analyzer was employed to study microstructure of air-entrained concrete with and without NS. The results demonstrate that the adsorption of NS at air bubble shell entrained by AEAs can densify the hydration products of the air pore wall and influence the pore size distribution, thereby improving the flexural strength and frost resistance of air-entrained concrete under low air pressure. The average air pore diameter of concrete with proper AEAs can be refined by 43.3% after adding NS. SEM, EDS and FTIR data analysis proves the adsorption of NS on the air bubble shell and differences in chemical composition of air bubble shell entrained by two types of AEAs. The differences in the composition of bubble shells result in diverse degree of NS optimized concrete performance. This study deepens our understanding into the fundamental mechanism of NS in concrete in Lap, which also prompts its application to create a sustainable built environment.

Hybrid hierarchical architectures possess significant possibility in construction of anode materials for advanced sodium ion batteries (SIBs). Herein, ZnS nanoparticles embedded in N-doped-carbon polyhedra and modified by Co4S3 nanoparticles (ZnS ⊂ N-C@Co4S3) with a hierarchical porous architecture, is designed using a self-assembly and associative sulfuration method. This ingenious nanoarchitecture frameworks possess several prominent merits. First, the N-doped-carbon skeleton as a scaffold for Co4S3 and ZnS can inhibit the agglomeration and buffer the volume expansion of the electrodes during cycling processes. Second, the abundant channels, rich interfaces and better conductivity for this architecture can benefit for the electrolyte permeation into the whole structure and shorten the diffusion pathway of the sodium ions. Impressively, the as-obtained hybrid frameworks deliver a stable capacity of 255.9 mAh g−1 in the 300th cycle at 2.0 A g−1, and superior rate capabilities when cycled at different currents. The enhanced sodium storage performance of this hierarchical multicomponent hybrid electrode indicates the importance of the advanced structure design with higher complexity for the energy storage.

In this paper, three kinds of P(AM-co-MAA) microgels with different anion contents were synthesized by inverse suspension polymerization with acrylamide (AM) and methacrylic acid (MAA). The modified mortar was prepared by cement and sand as fillers and P(AM-co-MAA) as internal curing agent. The swelling behavior of P(AM-co-MAA) microgels with different anion contents in aqueous solutions was studied. The effects of P(AM-co-MAA) and commercial superabsorbent polymer (SAP) on the flowability, mechanical properties, drying shrinkage and microstructure of mortar were investigated. The results showed that the presence of multivalent cations (mainly Ca2+) weakened the absorption capacity of microgels in cement filtrate. Spherical microgels had no negative effects on the flowability and mechanical properties of cementitious materials. The compressive strength of modified mortar can be significantly improved at later curing stage due to dome structure and internal curing. Furthermore, the water content of modified mortar with 0.1% additions of microgel decreased, and the drying shrinkage rate of the modified mortar was about 36% lower than that of cement mortar without microgels. It can also be observed that a large amount of macro pores were not formed around the microgels.

The objective is to establish a comprehensive paving performance index (PPI) for quantifying the cost-effectiveness of modified asphalt binders. Eight modified binders were characterized using a suite of mechanical tests for the rutting, fatigue, yield, and recovery properties. The current specification parameter for each test was evaluated to establish the individual performance index (IPI). The developed PPI considered contributions from all IPIs and was found to correlate reasonably well with cost via a linear function, except for the crumb rubber (CR) modified binder. By evaluating the binder performance per unit price, CR was identified as the most cost-effective modifier.

To guarantee the large‐scale and sustainable utilization of renewable clean energy, sodium‐ion batteries are considered as one of the most promising energy storage tools. In article number 1801222, Wenpei Kang, Daofeng Sun, Yuliang Cao, and co‐workers report a potential anode material of interlayer‐expanded MoSe2/phosphorus‐doped carbon hybrid nanospheres coated by anatase TiO2 (denoted as MoSe2/P‐C@TiO2), exhibiting unprecedented cycling stability and ultrafast pseudocapacitive sodium storage capability.

Developing suitable cathode materials is essential to promote the development of sodium ion batteries (SIBs). In this work, Ni, Cu co-substituted P2-type Na0.67Mn0.7Cu0.15Ni0.15O2 microspheres are designed and synthesized through high temperature solid reaction using MnO2 template. Compared with pristine Na0.67MnO2, or monometal substituted Na0.67Mn0.7Ni0.3O2 and Na0.67Mn0.7Cu0.3O2, this binary metal co-substituted Na0.67Mn0.7Cu0.15Ni0.15O2 microsphere shows markedly enhanced electrochemical performance as cathode material for SIBs, especially for long-term cycling stability and high rate capability. For the rate capability measurements, when the current increases from 50 mA g−1 to high current of 2000 mA g−1 (40-folds increase), the capacity retention can be kept for 65.0%. And for the long-term cycling performance within 1000 cycles, a capacity of 74.1 mAh g−1 can be maintained in the voltage range of 2.0–4.0 V at high current of 1000 mA g−1, corresponding to a capacity retention of 88.1%. The impressive cycling stability and rate capability should be attributed to the stable microsphere structure and synergistic effect of electrochemical active Ni, Cu co-existence in P2 phase lattice. Coupled with presodiation MoSe2/P-C anode and assembled into full cells, the specific capacities are almost matched with those in half-cells, delivering a considerable energy density of 200 Wh Kg−1.

Porous asphalt wearing course has been widely used all over the world. Due to the high porosity and the good stone quality, porous asphalt provides good skid resistance, noise reduction ability and reduces significantly splash and spray in wet conditions. In Asian countries, high viscosity modified bitumen is commonly used as binder of porous asphalt mixture to increase the anti-raveling and rutting resistance property. However, because of the open gradation and rapid aging of the binder, raveling and raveling-induced pitting are still the most common type of destruction for porous asphalt wearing course in long term service. To prevent the occurrence of raveling, a study on the preventive maintenance materials for porous asphalt wearing course based on high viscosity modified bitumen is conducted. Based on the mechanisms of the raveling destruction, the properties for preventive maintenance materials to be developed are proposed correspondingly. Then laboratory measurements are carried out to investigate the performance of the materials, including tests on apparent viscosity, cohesion, adhesion to stone, rejuvenation effect and properties of porous asphalt mixture treated with the preventive materials. Based on the experiment results and the analyses, the performances of different preventive maintenance materials are concluded. It provides a technical support for preventive maintenance engineering on porous asphalt using high viscosity modified bitumen as binder.

The castor oil-polyurethane pre polymer (C-PU) terminated with NCO group was synthesized by renewable castor oil and liquefied MDI as asphalt modifier and C-PU modified asphalt with 10–40 wt% C-PU were prepared. Classical and rheological properties were investigated. The results showed that, softening point and ductility of C-PU modified asphalt were both increased, while penetration was decreased to some extent. With the increase of C-PU, the modulus increases and the phase angle decreases which showed an improved resistance to deformation. Among them, 30 wt% is the best dosage. Moreover, Brookfield viscosity of the modified asphalt varies little at 130 °C with the time prolonged and a fairly homogeneous dispersion system was observed by microscope, which indicated that the thermal stability of modified asphalt at 130 °C was good. FTIR analysis showed that C-PU with NCO terminated could react with water and active hydrogen in asphalt and air. The transition from the simple physical blending with asphalt to slowly chemical modification process could explain the improvement of the asphalt performance.

The mechanical impedance is a measure of the ability of a structure to resist motion when subjected to a given force. It has been considered related with tyre–road noise level of road surface. However, this parameter is seldom used to characterize mixtures in asphalt mixture design. In this study, the relationship between the mechanical impedance and the pavement stiffness is investigated based on laboratory and in-situ measurements. Mechanical impedance is tested by an impedance hammer device, while the stiffness is measured by the indirect tension test (ITT) method. Different types of road surfaces are taken into account, including thin layer noise reducing surfacing, dense surface and poro-elastic road surface. The influences of mixture compositions on mechanical impedance and stiffness are discussed. Statistical relationship between the stiffness and the mechanical impedance is developed based on the measurement results. Advices for noise reducing road surface design by considering mechanical impedance are given according to the research findings.

Core-multishelled structures with controlled chemical composition have attracted great interest due to their fascinating electrochemical performance. Herein, a metal-organic framework (MOF)-on-MOF self-templated strategy is used to fabricate okra-like bimetal sulfide (Fe7 S8 /C@ZnS/N-C@C) with core-double-shelled structure, in which Fe7 S8 /C is distributed in the cores, and ZnS is embedded in one of the layers. The MOF-on-MOF precursor with an MIL-53 core, a ZIF-8 shell, and a resorcinol-formaldehyde (RF) layer (MIL-53@ZIF-8@RF) is prepared through a layer-by-layer assembly method. After calcination with sulfur powder, the resultant structure has a hierarchical carbon matrix, abundant internal interface, and tiered active material distribution. It provides fast sodium-ion reaction kinetics, a superior pseudocapacitance contribution, good resistance of volume changes, and stepwise sodiation/desodiation reaction mechanism. As an anode material for sodium-ion batteries, the electrochemical performance of Fe7 S8 /C@ZnS/N-C@C is superior to that of Fe7 S8 /C@ZnS/N-C, Fe7 S8 /C, or ZnS/N-C. It delivers a high and stable capacity of 364.7 mAh g-1 at current density of 5.0 A g-1 with 10 000 cycles, and registers only 0.00135% capacity decay per cycle. This MOF-on-MOF self-templated strategy may provide a method to construct core-multishelled structures with controlled component distributions for the energy conversion and storage.

Despite the fulfilling progress in fabricating metal chalcogenides-based battery electrodes, most effort focuses on construction of hybrid architectures and/or foreign elemental doping for improving electrochemical performance. In this work, we report a self-template strategy to synthesize hexagonal SnS2 and orthorhombic SnS nanoplates with abundant S vacancies as advanced anode materials of lithium-ion batteries (LIBs). Phase evolution from hexagonal SnS2 to orthorhombic SnS by thermal annealing is investigated. The resultant tin sulfide nanoplates featuring abundant S vacancies and decreased bandgaps can provide more active sites, higher Li+-ion diffusion mobility and better electronic conductivity, which are beneficial for improving electrochemical reaction kinetics. Consequently, both the S-vacancy-rich SnS2 (SVR-SnS2) and the SVR-SnS nanoplates show significantly enhanced cycling performance and rate capability compared with the interlayer-expanded SnS2 (IE-SnS2) nanoplates. Remarkably, the SVR-SnS nanoplates can exhibit outstanding rate capability (510 mAh g−1 at 10 A g−1) and excellent long-term cycling performance. A reversible capacity as high as 765 mAh g−1 at a high current of 2 A g−1 can be delivered even after 1200 cycles. It is the best cycling performance of SnS-based electrodes for LIBs to date. Besides the benefits from S vacancies, the pseudocapacitive contribution is also responsible for the fast and stable lithium storage capability. The present work provides a new strategy for modulating 2D layered tin sulfide nanoplates as promising anode materials for LIB applications.

A porous metal–organic framework [Ba(H2 LLOMe 2−)·DMF·H2O]·2DMF (UPC‐2) (H4 LLOMe = 4ʹ,4ʹʹʹ‐(2,3,6,7‐tetramethoxyanthracene‐9,10‐diyl)bis([1,1ʹ‐biphenyl]‐3,5‐dicarbo‐xylic acid N,N‐Dimethylformamide [DMF]), which can act as an excellent chemiluminescence microreactor, is designed and constructed. In the framework of UPC‐2, the catalytic Ba cluster and electron‐rich anthracene fluorescent centers are fixed and interconnected in an orderly fashion, and this can shorten the energy transfer path and weaken the relaxation of the chemiluminescence process. Meanwhile, the rhombic channels of UPC‐2 can provide a proper diffusion ratio of reactants to support a stable and continuous energy supply. The UPC‐2 chemiluminescence microreactor exhibits an ultrastrong and long‐lasting light emission, which possesses potential application in emergency lights and biological mapping. The concept of the chemiluminescence microreactor and its construction using a metal–organic framework as a platform will promote further research in the design and fabrication of functional MOFs for chemiluminescence applications., To enhance the light‐emitting intensity and extend the lasting time of chemiluminescence (CL) reaction, a concept of “integrated chemiluminescence microreactor” is proposed and constructed using a metal–organic framework as a platform. The as‐obtained microreactor presents an ultrahigh light‐emitting intensity which could be observed by the naked eye even after 540 min.

Na3V2(PO4)3 with NASICON (sodium superionic conductor) structure, has been considered as a potential cathode material for sodium ion batteries (SIBs). Herein, sustainable phosphorus sources of phytic acid is adopted to synthesize carbon coated Na3V2(PO4)3 (Na3V2(PO4)3/C-1) nanoparticles. Phytic acid can chelate with VO2+ ions and in-situ transform into tightly coated carbon. As a result, the dispersivity and size-distribution of Na3V2(PO4)3/C-1 particles are ideal, which will provid an enhanced conductivity and structure stability as cathode material for SIBs. For the rate performance, when the current increases from 0.05 A g−1 to 5.0 A g−1, a capacity of 70.7 mA h g−1 is maintained, corresponding to a capacity retention of 73.7 %. For the long-term cycling at current of 5.0 A g−1, there is only 0.0027 mA h g−1 capacity decay per cycle, giving a high capacity retention of 83.9 % after 5000 cycles. The high rate capability and cycling stability is attributed to the lower charge transfer resistance and higher diffusion coefficient of sodium ion, proved by the galvanostatic intermittent titration technique and electrochemical impedance spectroscopy.

Due to rich redox sites and high electronic conductivity, multi-metal sulfides are considered as a competitive candidate for energy storage and conversion. Recently, nanostructure engineering and composition control are usually employed to enhance the electrochemical performance of metal sulfides. Herein, Fe3Ni6S8 solid solution anchored on N-doped carbon matrix (denoted as Fe3Ni6S8/N–C) with hierarchical structure is constructed through a facile freeze-drying/carbonization method using NaCl template. Fe3Ni6S8/N–C hybrid consists of interconnected porous carbon networks and nanoflakes can act as robust anode for sodium ion batteries (SIBs) and considerable electrocatalysts for hydrogen evolution reaction (HER). It delivers high capacity of 450.1 mAh g−1 at 10 A g−1, giving high capacity retention of 68.7% compared to that at 0.1 A g−1. And stable capacities of 596.6 mAh g−1 can be maintained for 180 cycles at 1.0 A g−1 as SIBs anode. When used as a HER catalyst, it exhibits a smaller Tafel slope of 55 mV dec−1 and superior long-term stability. The Fe3Ni6S8/N–C hierarchical structure can provide enhanced conductivity, rich active sites and rapid electron/ion transport channels, leading to impressive electrochemical performance.

High-viscosity modified asphalt is mainly used as a binder for porous asphalt in China and Japan. In order to meet the demand for using porous asphalt under high temperature condition in Africa, high-viscosity asphalt made from low-grade matrix asphalt, which is commonly used in Africa is investigated. Based on simulation of local climate in Africa, the suitable range of high viscosity additive content for different matrix asphalt was obtained by analyzing dynamic viscosity of the asphalt. Through PG high temperature grading, multi-stress repeated creep, accelerated fatigue, temperature sweep and other tests, changes of high temperature, anti-fatigue and anti-shear indicators before and after modification were compared and analyzed and effects of different matrix asphalt were also studied. Finally, considering engineering requirements, mixing and compaction temperatures of various high-viscosity modified asphalt were determined through study of viscosity-temperature characteristics. This research provides a support for preparation of high-viscosity modified asphalt and porous asphalt mixture by using low grade asphalt. The research achievements can help to guide the material design and application of porous asphalt in Africa and other high temperature areas.

To study the regular properties of modified bio-asphalt, analytical and measuring methods, including softening point, penetration, and ductility tests, were employed to analyze the improvement of properties in different mixing proportions of bio-asphalt and modified asphalt. Results indicated that after mixing bio-asphalt with modified asphalt, the penetration of bio-asphalt declined constantly with an increment proportional to the modified asphalt. The excellent performance at high temperature of the two kinds of bio-asphalts was affected by the mixing of modified asphalt. According to the analysis of temperature stability, the ductility of bio-asphalt significantly improved after mixing with modified asphalt, although the softening point declined. The stiffness and brittleness of bio-asphalt at low temperature improved as well, particularly in SBS and SBR modified asphalts. Results improved as the proportion of modified asphalt increased.

Different modifiers composed of polyethylene glycol, paraformaldehyde, polystyrene, and polyphosphoric acid at different ratios (designated CD-0, CD-1, CD-2. CD-3, and CD-4) were added to coal tar pitch. The resulting modified pitches were prepared and designated control D-0 and D-1, D-2, D-3, and D-4, correspondingly. The objective of this study was to evaluate the properties of the control and modified coal tar pitches by the dynamic shear rheometer (DSR) test and microscopic imaging technology. The complex shear modulus G* and phase angle δ of the modified coal tar pitches decreased with increased temperature, which indicated a decline in the gradual capacity for resistance to permanent deformation at high temperatures. There was good correlation between the Christensen-Andersen-Marasteanu (CAM) model and the complex modulus master curve of the modified coal tar pitches. The test results showed that D-4 had a higher complex viscosity η* than that of the control D-0 and the other modified coal t...

Based on multielectron conversion reactions, layered transition metal dichalcogenides are considered promising electrode materials for sodium-ion batteries, but suffer from poor cycling performance and rate capability due to their low intrinsic conductivity and severe volume variations. Here, interlayer-expanded MoSe2/phosphorus-doped carbon hybrid nanospheres coated by anatase TiO2 (denoted as MoSe2/P-C@TiO2) are prepared by a facile hydrolysis reaction, in which TiO2 coating polypyrrole-phosphomolybdic acid is utilized as a novel precursor followed by a selenization process. Benefiting from synergistic effects of MoSe2, phosphorus-doped carbon, and TiO2, the hybrid nanospheres manifest unprecedented cycling stability and ultrafast pseudocapacitive sodium storage capability. The MoSe2/P-C@TiO2 delivers decent reversible capacities of 214 mAh g-1 at 5.0 A g-1 for 8000 cycles, 154 mAh g-1 at 10.0 A g-1 for 10000 cycles, and an exceptional rate capability up to 20.0 A g-1 with a capacity of ≈175 mAh g-1 in a voltage range of 0.5-3.0 V. Coupled with a Na3V2(PO4)3@C cathode, a full cell successfully confirms a reversible capacity of 242.2 mAh g-1 at 0.5 A g-1 for 100 cycles with a coulombic efficiency over 99%.

Gold- or carbon-based photothermal therapy (PTT) agents have shown encouraging therapeutic effects of PTT in the near-infrared region (NIR) in many preclinical animal experiments. It is expected that gold/carbon hybrid nanomaterial will possess combinational NIR light absorption and can achieve further improvement in photothermal conversion efficiency. In this work, we design and construct a novel PTT agent by coating a carbon nanosphere with patchy gold. To synthesize this composite particle with Janus structure, a new versatile approach based on a facile adsorption-reduction method was presented. Different from the conventional fabrication procedures, the formation of patchy gold in this approach is mainly a thermodynamics-driven spontaneous process. The results show that when compared with the conventional PTT agent gold nanorod the obtained nanocomposites not only have higher photothermal conversion efficiency but also perform more thermally stable. On the basis of these outstanding photothermal effects, the in vitro and in vivo photothermal performances in a MCF-7 cells (human breast adenocarcinoma cell line) and mice were investigated separately. Additionally, to further illustrate the advantage of this asymmetric structure, their potential was explored by selective surface functionalization, taking advantage of the affinity of both patchy gold and carbon domain to different functional molecules. These results suggest that this new hybrid nanomaterial can be used as an effective PTT agent for cancer treatment in the future.

This paper investigates the effect of three warm mixture asphalt (WMA) additives on the high temperature rheological properties of both unaged and rolling thin film oven (RTFO) aged crumb rubber modified (CRM) binders. The WMA additives used in this study include Sasobit, RH and Advera. The ambient 40-mesh tire rubber with the concentrations of 10%, 15%, 20%, and 25% by the weight of asphalt binder, respectively, was used in this study. Dynamic shear rheometer (DSR) was employed to measure the complex modulus (G∗) and phase angle (δ) of CRM binders at various testing temperatures. The statistical analysis of variance (ANOVA) was applied to quantify the effects of WMA additives on the CRM binders’ rutting resistance properties. It was found in this study that, the three WMA additives could all improve the CRM binders’ resistance to rutting, and greatly improved high-temperature portion of the performance grade (PG) of CRM binders. It is found that Sasobit had the most remarkable effect on G∗ of both unaged and RTFO-aged CRM binders, RH only had significant effect on G∗ of RTFO-aged binders, Advera’s effect was indistinctive. Furthermore, WMA additives’ effect on δ was not conclusive.

Porous asphalt wearing courses are a type of high-performance wearing course with technical features such as high skid resistance and low noise, as well as abilities that inhibit water mist during rainy weather conditions, prevent skidding during high-speed driving, and alleviate dazzle light during night driving. With the gradual popularization of this high-performance wearing course in China, the problem of its matched markings has become a growing concern. Hot melting scrape coating markings are commonly used in porous asphalt wearing course designs. However, this marking technology has associated problems. For example, its application often blocks the pores of the porous asphalt and causes surface water to gather on rainy days. It also attenuates the functional properties of porous asphalt. Additionally, material consumption increases because of marking infiltration. The proposed permeable marking technology addresses issues of performance concerning drainability, high skid resistance, and all-dimensional and all-weather reflection. Technical problems, such as pore blockage from ordinary markings, are successfully resolved by using an active bicomponent marking material through its reaction into membranes and in combination with rotating-coating type or discontinuous-extrusion type marking application technology. From the laboratory and in situ tests, it was determined that adhesion, reflection in the dark, wet driving conditions, and pavement skid-resistance value from the marking are improved.

Thin layer wearing course is commonly used as a noise-reducing pavement in some European countries. The noise-reducing performance is realized because of small surface texture and higher sound absorption properties. In this paper, the investigation focuses on the sound absorption properties of this type of road surface. Laboratory measurements were carried out to observe the sound absorption curves of the thin layer surfacing course. Both slab specimens produced in the lab and cores drilled from practical road sections were involved in the tests. It was found that surfaces with an air voids content less than 12 % show a smaller sound absorption coefficient, whereas surfaces with air voids content higher than 17 % have promising sound absorption properties. Acoustical models were also developed to describe the sound absorption of the thin layer wearing course. The modeling curves fit the test results better when connected air voids were taken into account. The models are considered applicable for examining the sound absorption coefficient with given mixture compositions, and they can also be used for evaluating the tire-road noise for a thin layer wearing course.

Packing model of aggregate is a very important issue in gradation design and research on asphalt mixture. The packing characteristics of coarse aggregate and fine aggregate can affect the skeleton and volumetric parameters, such as VMA (Void in Mineral Aggregate), of asphalt mixture respectively. In this study, based on the ideal packing model of aggregate, the 2-D packing model, which is a random distribution and compacted contact of different size aggregates, is built and the mathematical solution to this model is figured out by using the geometric theory of space topology. The model has been programmed and visualized by using Visual Basic language. The impact of gradation on the skeleton and VCA (Void in Coarse Aggregate), and the effect of fine aggregate packing on VMA can be analyzed by using this model and algorithm. The model is helpful to the gradation design, analysis and evaluation for asphalt mixture.

The application of crumb-rubber modifier (CRM) in asphalt mixtures has been proven to increase the viscosity of CRM binders. In recent years, warm mix asphalt (WMA) additives have been employed to CRM binders to lower their viscosity at high temperatures, allowing a decrease in the mixing and compaction temperatures. The objective of this research is to investigate the viscosity and storage stability of rubberized WMA binders with different tire rubber concentrations and WMA additives. The tire rubber of 40-mesh, with concentrations of 10 %, 15 %, 20 %, and 25 % by weight of a Superpave performance grade (PG) 64-22 asphalt binder, were used in this study along with the WMA additives, such as Sasobit, RH and Advera. Viscosity tests were conducted on the rubberized WMA binders using the rotational viscometer at four temperatures (135, 160, 177, and 190°C). The statistical analysis of variance (ANOVA) was applied to quantify the respective effects of the influencing factors on the CRM binder’s viscosity. The test results indicated that the addition of crumb rubber could greatly increase the viscosity of asphalt binders, which could be improved continuously at increased crumb-rubber concentrations. However, when considering different WMA additives, the crumb rubber showed different effects on the viscosity of the binder. The three WMA additives could all reduce the viscosity of the CRM binder; in addition, RH had the most significant effect on viscosity reduction. It was also found that the CRM binders with WMA additives had good storage stability. For example, the viscosity of the CRM binder with 10 % rubber concentration and RH only increased by 3.8 % after being stored for 4.5 h.