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A novel bio-fertilizer, produced from prickly ash seeds (PAS), Bacillus subtilis and biochar, was evaluated for its disease-preventing potential on tobacco black shank caused by Phytophthora nicotianae. The results showed that biochar promoted the growth of Tpb55 in PAS and increased the pH of the organic fertilizer. The final concentration of B. subtilis could reach 1.7 × 1010 cfu g−1 in the biological organic fertilizer (PBB) under the optimal medium under conditions of solid-state fermentation. PBB exhibited a strong fumigation effect on P. nicotianae, including inhibiting mycelium growth, reducing the disease severity and decreasing the pathogen population in rhizospheric soil. PBB treatment also could significantly increase the pH of acidified soil and improve soil nutrition content such as available K, alkali hydrolysable N and organic carbon. High-throughput pyrosequencing of 16S and 18S rRNA genes revealed that 4% PBB addition in soil had significant effects on the diversity and richness of fungi but not on that of bacteria. The microbial community structure was also shifted after PBB treatment. Some potentially beneficial microbes such as Bacillus, Mucor, Cunninghamella, Chitinophaga and Phenylobacterium were enriched, while potential pathogen Fusarium was significantly decreased. In conclusion, the agricultural waste PAS combined with biochar can replace soybean as a source for the production of biocontrol B. subtilis Tpb55, and the novel bio-fertilizer could effectively control tobacco black shank by pathogen inhibition, soil nutrient improvement and shifting the rhizomicrobial community.

Microcapsules with toluene-di-isocyanate (TDI) as core and paraffin as shell for self-healing of concrete were prepared using melt condensation method, and the effects of preparation temperature, agitation rate and paraffin/TDI mass ratio on core fraction of microcapsules were studied. The size distribution and morphology of microcapsules were characterized by laser particle size analyzer and scanning electron microscopy (SEM). Components of the microcapsules were analyzed by Fourier transform infrared spectrometer (FTIR). Finally, the effect of microcapsules on self-healing ability of mortars was evaluated, which indicated that preparation temperature, agitation rate and paraffin/TDI mass ratio had significant effect on core fraction of microcapsules. The optimum microcapsules could be prepared with a paraffin/TDI mass ratio 1:2 and an agitation rate 600 rpm at 75 °C. The core fraction of microcapsules prepared with optimum parameters was 66.5%, and the particle size was between 30 and 300 µm, mainly concentrated on 90 μm. SEM showed that the microcapsules were regular spheres and the shell thickness was about 1/10 of the diameter. FTIR confirmed that the TDI was successfully encapsulated in the paraffin shell. Compared with the control mortar, compressive strength of the mortar with 3% microcapsules (by mass of cement) increased by 28.2%. The reserved ratio of compressive strength was 77.2% under 60% fc0 pre-load after 48 h self-healing. The cracks with a width of less 0.4 mm on the mortar were rapidly self-healed by the microcapsules in 6 h.

Layered double hydroxides (LDHs) with different particle sizes (75 nm, 115 nm, 180 nm and 300 nm which were marked with LDHs-75, LDHs-115, LDHs-180 and LDHs-300) were characterized by scanning electron microscope, UV–vis reflection and absorption spectrophotometer and laser scatter meter. Furthermore, this paper investigated the influence of LDHs with different particle sizes on the rheological properties of bitumen before and after ultraviolet aging by temperature susceptibility test, dynamic shear rheometer test (DSR) and IR spectra test (FTIR). The researches reveal that LDHs-180 hold the strongest UV shielding performance. The temperature susceptibility of pristine bitumen and LDHs-75, LDHs-115, LDHs-180, LDHs-300 modified bitumen after aging decreased by 9.01%, 6.36%, 3.98%, 2.15% and 5.49%, respectively, which indicate LDHs-180 is more beneficial to weaken the decrease of bitumen temperature susceptibility after aging. Similarly, LDHs-180 modified bitumen show less variation in rheological properties than other bitumen samples after aging. This implies that LDHs-180 could mitigate the influences of UV aging on the rheological properties of bitumen more availably. In addition, the FTIR analysis further shows that the carbonyl and sulfoxide index of LDHs-180 modified bitumen is the smallest after aging, which indicates LDHs-180 is more helpful for improving bitumen anti-UV aging properties than that of LDHs-75, LDHs-115 and LDHs-300.

Lignosulfonate (LS) grafted layered double hydroxides (LDHs) were prepared through covalent bonding with diisocyanate (diphenyl-methane-diisocyanate (MDI), toluene-2,4-diisocyanate (TDI) or isophorone diisocyanate (IPDI)), and were characterized by Fourier transform infrared (FTIR) spectrometer, X-ray diffraction (XRD), scanning electron microscopy (SEM) and ultraviolet and visible (UV–vis) spectroscopy. The degree of grafting (Dg) and mass proportion (Mp) had also been calculated. Then LS grafted LDHs modified bitumen was investigated using high temperature storage stability, physical properties measurement and thin-layer chromatography with flameionization detection test. FTIR and XRD showed that LS was successfully grafted to LDHs via covalent linked by diisocyanate. SEM displayed that LS grafted LDHs represented a stable cross-linked structure and had weaker surface agglomeration compared to LDHs. Dg and Mp of LS grafted LDHs linked by MDI (LS-m-LDHs) respectively reached up to 71.68% and 2.53:1, representing excellent grafting effect. The UV–vis analyses displayed that LS grafted LDHs had better UV absorbing ability than LDHs, which had a combined effect of chemically absorbing and physically reflecting UV light. Storage stability test expressed that the compatibility between bitumen and LDHs was improved prominently by the grafting of LS. Before and after aging, the variations of retained penetration ratio (RPR), ductility retention rate (DRR), softening point increment (SPI), viscosity aging index (VAI) and the colloid stable index (CI) of LS grafted LDHs modified bitumen were smaller compared to LS modified bitumen and LDHs modified bitumen, which illustrated that LS grafted LDHs exhibited better anti-UV aging ability of bitumen in comparison with LDHs and LS. In improving the aging resistance of bitumen. LS-m-LDHs were superior to LS grafted LDHs linked by TDI and LS grafted LDHs linked by IPDI.

Generation of kidney organoids using autologous kidney stem cells represents an attractive strategy for treating and potentially replacing the failing kidneys. However, whether adult mammalian kidney stem cells have regenerative capacity remains unknown. Here, previously unidentified adult kidney Sca1

Self-healing microcapsules show great potential in extending the service life of concrete, but it is a challenge to achieve the smart release of the healing agent from the microcapsules. In this research, Novel Microcapsules Raptured by Microwave (NMRM) with unique core–shell structure for self-healing concrete were successfully produced. The core content was calculated and the surface morphology and size distribution of NMRM were explored by Scanning Electron Microscope (SEM) and Dynamic Light Scattering (DLS). The temperature variations of specimens were monitored by a thermal infrared imager. Furthermore, the effects of NMRM dosage on the fundamental performance of concrete was investigated and self-healing behavior of the mortar and concrete were evaluated. As a result, rapture of microcapsules with 5% graphite can be quickly triggered under the microwave irradiation. The 60% fc0 pre-damaged concrete with 5% NMRM possessed 92.6% of CSRR. The purpose of this investigation is to provide a new trigger for microcapsule rupture on the specific location with cracks at the right time for self-healing concrete.

The surface free energy and related parameters of asphalt binder affect the wettability of asphalt binder to aggregate and its moisture sensitivity. In this research, the surface free energy and related parameters of SBS modified bitumen (SMB) after aging/rejuvenating were tested and analyzed. And then based on this data, the effect of common rejuvenator cashew shell oil and active isocyanate rejuvenators on the water damage resistance and moisture sensitivity were evaluated and predicted. The results indicated that the surface free energy of SMB decreased after aging, while rejuvenators all can enhance the surface free energy. The cohesion work of aged SMB increased after rejuvenating, and the adhesion work between aged SMB and granite were enhanced by 12.4% at least with the addition of rejuvenators, namely, rejuvenators can improve its cracking resistance and interface stability, and active rejuvenator hexamethylene diisocyanate showed the best performance. Water boiling test showed that the adhesion grade of SBS modified bitumen on granite decreased from adhesion grade 5 to adhesion grade 3 after aging, while active rejuvenators can bring the adhesion grade of aged SMB on granite to the original level. This paper would be helpful to understand the moisture resistance mechanism of rejuvenated SBS modified asphalt mixture with active regeneration technology.

Ion chelator can chelate calcium ions and migrate in cement-based materials to promote self-healing of cracks. This paper investigated the migration and self-healing abilities of ion chelator in cement-based materials by a novel method. In this method, control mortar without ion chelator and self-healing mortar with ion chelator are poured into the same mold, cracks at different locations of the two kinds of mortars are prefabricated, and the migration of ion chelator from self-healing mortar to the control mortar is assessed by observing the self-healing process of crack in control mortar. Meanwhile, the microstructure and chemical component of self-healing product in cracks at different locations of the control mortar was characterized through scanning electron microscope (SEM) and X-ray diffraction (XRD). The results show that the self-healing ability of control mortar is closely related to the migration distance of ion chelator. When the migration distance of the ion chelator was 2 cm, the crack with a width of 0.37 mm can be sealed after curing for 7 d. When the migration distance of the ion chelator was 5 cm, the crack with a width of 0.26 mm can also be repaired after curing for 7 d. Through SEM observation and XRD analysis, it can be found that the ion chelator promotes the formation of a large number of calcite crystals for sealing the cracks in the control mortar. However, the calcite crystals at the crack will become loose with the increase of the migration distance of the ion chelator.

Ion chelator is a novel crystalline additive which can chelate Ca2+ and migrate in concrete to promote self-healing of surface crack and internal pore. In order to further explore the effect of ion chelator on hydration process of cement, the hydration heat, chemically bound water, compressive strength, hydration products, pore-size distribution and microstructure of cement paste with ion chelator were investigated in this paper. Results of the experiments showed that the ion chelator accelerated the hydration of the cement paste. Incorporation of ion chelator in cement greatly enhanced the chemically bound water content and the mechanical property. Compared with control cement paste, the chemically bound water content and compressive strength of cement paste with 0.5 wt% ion chelator increased by 13.3% and 16.8% after curing for 28 days. According to the DTA-TG and XRD tests, the ion chelator can promote the hydration of C3S and C2S, which was conducive to the generation of calcium silicate hydrate gels. Furthermore, the addition of ion chelator improved the pore-size distribution and microstructure of cement paste, and a large number of floccules and needles appeared in the pores of cement paste.

In order to evaluate the influence of silane coupling agent modified zeolite warm mix additives on the properties of asphalt, the physical and rheological properties as well as chemical structure of asphalt with zeolite, γ-ammoniapropyltriethoxysilane modified zeolite (KH550-zeolite) and γ-(2,3-epoxypropoxy)propytrimethoxysilane modified zeolite (KH560-zeolite) before and after thin film oven test (TFOT) aging were thoroughly investigated. The results showed that, compared with zeolite, KH550-zeolite and KH560-zeolite made the softening point of asphalt increase more, and whose penetration and ductility decrease less, which indicated that KH550-zeolite and KH560-zeolite (especially KH560-zeolite) could enhance the high-temperature properties and had less effect on the penetration and ductility of asphalt. The temperature susceptibility of asphalt was clearly reduced and the rutting factor (G*/sinδ) was enhanced after the introduction of silane coupling agent modified zeolites compared with zeolite. After the TFOT aging, the performance of asphalt with silane coupling agent modified zeolites (especially KH560-zeolite) had a little change. In a word, KH550-zeolite and KH560-zeolite as warm mix additives had a positive effect on the physical, rheological and anti-aging properties of asphalt.

Ion chelator is a kind of crystalline additive which can accelerate the precipitation of calcium carbonate in cracks of cement-based materials. In this paper, the influences of ion chelator and CO2-rich environment on self-healing capabilities of cement mortar were investigated. The mortars with or without ion chelator were subjected to two gas environments (air and CO2-rich) and three exposure conditions (no water, water contact and water immersion), respectively. The self-healing rate of cracks, water permeability and water absorption of the healed mortars, and microstructure of self-healing product were used to assess the self-healing capability of mortars. The results indicated that the self-healing ability of the mortars cured in CO2-rich environment is stronger than that of the mortars cured in air environment. The excellent self-healing ability of the mortars with ion chelator needs to be stimulated by water contact or water immersion. The relative permeability coefficient and water absorption coefficient of mortar with ion chelator in the CO2-rich environment under water contact or water immersion conditions were significantly reduced. In addition, the bottom surface crack of mortar has better self-healing ability than the top surface crack of mortar. The bottom surface crack up to 0.46 mm can be healed after curing for 28 d when the mortars with ion chelator were cured in the CO2-rich environment under water immersion condition. Scanning electron microscopy showed that the particle sizes of self-healing products (CaCO3) in bottom surface crack were larger than that in top surface crack.

Ion chelator can promote the self-healing process of cement-based materials. The aim of present study is to investigate the effect of ion chelator on microstructure and properties of cement-based materials under sulfate dry-wet cycle attack. The micromorphology and pore structure of mortar were characterized by scanning electron microscope (SEM) and nuclear magnetic resonance (NMR). The impermeability of mortar was evaluated by chloride diffusion coefficient. Meanwhile, mass loss, mechanical strength, and corrosion resistance coefficient (K) of mortar were measured. The results showed that ion chelator could improve microstructure and mechanical properties of cement-based materials by enhancing their self-healing ability. After 60 cycles of sulfate dry-wet, SEM showed that there was a large degree of erosion formed on the surface of control mortar (CM), while slight erosion occurred on the surface of mortar with ion chelator (MCA). NMR indicated that the proportion of harmful pores (≥0.1 μm) in CM and MCA was 50.19% and 42.86%, especially, the proportion of harmful pores from 0.25 μm to 25.0 μm in mortar is obviously reduced with the addition of ion chelator. And the compressive strength of MCA was 33.6% higher than that of CM, and the chloride diffusion coefficient of MCA was 25% lower than that of CM. Meanwhile, the mass loss ratios of CM and MCA were 1.78% and 0.91% and the K values of CM and MCA were 0.79 and 0.92 respectively. Conclusion can be drawn that ion chelator significantly improves the microstructure and properties of cement-based materials under sulfate dry-wet cycle attack.

The ambient temperatures have significant effect on self-healing capabilities of concretes with microcapsules. Self-healing capabilities of mortars with different shell composition (paraffin, paraffin/PE wax and nano-SiO2/paraffin/PE wax) microcapsules containing toluene-di-isocyanate under the temperature of 10 °C, 30 °C, 50 °C and 60 °C were investigated in this paper. The compressive strength, chloride diffusion coefficient and pore size distribution of mortars containing microcapsules before and after self-healing were characterized by mechanical property test, rapid chloride migration test and nuclear magnetic resonance, respectively. The crack healing ratio of mortars during self-healing period were measured. The self-healing capabilities of mortars containing different microcapsules raised with the increase from 10 °C to 50 °C. Nevertheless, when the temperature reached 60 °C, the self-healing capability of the mortar containing paraffin microcapsules (AM1) decreased obviously, while the self-healing capabilities of the mortars containing paraffin/PE wax microcapsules (AM2) and nano-SiO2/paraffin/PE wax microcapsules (AM3) were almost unchanged. The self-healing capability of AM3 was superior to that of AM1 and AM2 at the same temperature. The compressive strength recovery rate, chloride diffusion coefficient recovery rate and harmful pores ratios of AM3 after pre-damaged at 50 °C for 7 d self-healing were 94.1%, 81.2% and 47.3%, respectively. When the ambient temperature reached 50 °C, the surface cracks of the mortar with three kinds of microcapsules could be completely self-healed in 5 h. However, when the temperature raised to 60 °C, the healing ratio of the crack in AM1 with a width of 0.4–0.5 mm decreased to 49.52% after 6 h self-healing. Meanwhile, the surface cracks of AM3 could be completely self-healed less than 3 h.

Ion chelator is a novel crystalline admixture used for improving self-healing capability of cementitious materials. Studies quantifying this self-healing behavior are limited to fresh-water making it unclear under seawater containing magnesium, sulfate and chloride ions. Therefore, the purpose of this paper is to investigate the effects of ion chelator on pore structure, mechanical property and self-healing capability of seawater exposed mortar. The pore size distribution was evaluated by nuclear magnetic resonance (NMR). The self-healing ability was quantified by compressive strength recovery and visible crack closure test, while the composition of crack healing products was analyzed by X-ray diffraction (XRD). The results indicated that ion chelator improves pore structure and compressive strength of mortar under seawater immersion. After 90 days seawater immersion, the proportion of harmful holes (>0.1 μm) in mortar with ion chelator (MCA) was 30.3%, which is lower than in control mortar (CM). The compressive strength of MCA under seawater for 90 days was 34.4 MPa, while that of CM was 27.4 MPa. The ion chelator enhanced the self-healing capability of pre-damaged mortar remarkably. After 28 days seawater immersion, compressive strength recovery rate of MCA under fresh-water and seawater was 94% and 80%, respectively. And the maximum crack width completely healed in MCA under seawater is up to 350 μm, while around 240 μm in MCA under fresh-water. XRD analysis revealed that the crack-healing products in MCA under seawater immersion were magnesium hydroxide and calcium carbonate.

High-purity solanesol can be used for pharmaceutical applications, but the current method for purifying solanesol has high cost and difficult continuous operation, and the use of molecular imprinting to purify natural products is a hot research topic of current research. Solanesol molecularly imprinted polymers were synthesized via emulsion polymerization for the first time. The morphology of the SSO-MIPs was observed with a scanning electron microscope, and the effects of the synthesis time, initiator dosage, functional monomer dosage, and cross-linking agent dosage on the adsorption effects under high-temperature and rapid synthesis conditions were discussed. The results demonstrate that the optimum synthesis conditions were a ratio of the template molecules to the functional monomers to the cross-linking agents of 1:8:30 (mol:mol:mol), 10 mg of the initiator, and a synthesis temperature of 70 &deg, C. The imprinting factor of SSO-MIPs synthesized under the optimized process was found to reach 2.51, and the SSO-MIPs synthesized by this method exhibited a good adsorption effect, emitted less pollution during the synthesis process, and are convenient for demulsification. This research reports a reliable method for the synthesis of solanesol molecularly imprinted polymers.

The increasing reclaimed asphalt pavement mixture causes environmental pollution and a waste of resource, which could be resolved by the asphalt recycling technology. In this paper, corn oil, waste engine oil, vacuum stream oil and cashew shell oil are used for rejuvenating aged SBS modified asphalt (ASMA), and the effect of composition, structure and thermal-oxidative stability of recycling agents on the early and long-term performance of rejuvenated binder are thoroughly investigated. The results indicate cashew shell oil with nut phenol derivatives has the best rejuvenating effect on ASMA, corn oil containing aliphatic hydrocarbons is more conducive to improving the low temperature performance of rejuvenated ASMA, and vacuum stream oil containing nonpolar alkane compound shows the worst regeneration effect. Meanwhile, simultaneous thermal analysis reveals nonpolar aliphatic hydrocarbons vacuum stream oil has the poorest thermal stability for its lowest initial decomposition temperature 146 °C, while initial decomposition temperature of cashew shell oil and corn oil are all over 200 °C. The changes of physical and rheological properties of cashew shell oil rejuvenated ASMA after aging are much smaller than that of others, which indicates cashew shell oil with excellent thermal-oxidative stability is more conductive to inhibiting the transition from viscosity to elasticity of rejuvenated binder in the aging process. While vacuum stream oil rejuvenated ASMA shows the most serious aging degree, suggesting the poor thermal-oxidative stability of recycling agents has adverse effects on the anti-aging properties of rejuvenated binder. Infrared spectrum analysis indicates the aging index growth rate of cashew shell oil rejuvenated ASMA is the smallest, also demonstrating the best aging resistance of cashew shell oil rejuvenated ASMA. The correlation coefficients between sulfoxide index and physical-rheological properties are almost all higher than 0.90, while that between sulfoxide index and physical-rheological properties are lower than 0.71, therefore sulfoxide index can be a better indicator for estimating the physical-rheological properties of rejuvenated SBS modified bitumen in the service.

Ion chelator is a novel crystalline admixture which can promote the self-healing of cracks in cement-based materials. In this paper, the self-healing capability of the surface and internal cracks of mortars with ion chelator of different age were investigated by the change of crack width, water permeability, recovery of compressive strength and X-ray computer tomography test. The results indicated that the surface crack up to 0.4 mm on the mortars with 0.5 wt% ion chelator pre-cracked at different age can be repaired after standard curing for 30 d. According to the water permeability test, the mortars with ion chelator pre-cracked at 3 d and 28 d have excellent self-healing ability for internal cracks, and the relative permeability coefficient of the mortars with 0.5 wt% ion chelator decreases most significantly. The compressive strength recovery test of mortars shows that ion chelator can promote the self-healing of internal cracks within the mortars. After curing for 56 d, the compressive strength recovery ratio of the mortars with 0.5 wt% ion chelator pre-loaded at 28 d reached 99.5%. And the X-ray computer tomography displayed that the self-healing process of cracks in mortars was from outside to inside.

The regeneration and utilization of reclaimed SBS modified bitumen require a high mixing and paving temperature, which result in a large of energy consumption and serious environment pollution. To reduce the mixing and paving temperature, polyethylene wax and active wax were selected to modify rejuvenated SBS modified bitumen, and their influences on the viscosity-temperature characteristics, physical and rheological properties of rejuvenated binder were thoroughly investigated in this research. The results indicate that active wax with epoxy terminal group shows a better performance on reducing the mixing and paving temperature of rejuvenated binder as compared with polyethylene wax. Meanwhile active wax modified rejuvenated binder shows the lowest flow activation energy 79.78 kJ/mol, indicating active wax is more helpful to improve the temperature sensitivity of rejuvenated binder at high temperature. Differential scanning calorimetry analysis shows the melting enthalpy of active wax is larger than that of polyethylene wax and polyethylene wax is easier to crystallize and solidify. These two warm additives all can improve the rutting resistance of rejuvenated binder. However, the cracking resistance of rejuvenated binder seriously decreases with the addition of polyethylene wax. While active wax could react with the active groups in rejuvenated binder that can inhibit the transition from viscosity to elasticity of rejuvenated binder and retain its excellent low-temperature performance more effectively as compared with polyethylene wax.