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In this study, three hydration heat controlling materials (HHCMs), respectively, containing pure hydroxyl (polyvinyl alcohol, PVA), carboxylic (polyacrylic acid, PAA) and ester groups (maleic acid-ethylene glycol ester, P(MA-EG)) were synthesized and mixed with cement-based materials, and the hydration heat and setting time of cement pastes and the SEMI adiabatic temperature rise and strength of mortars were tested. The results showed that PAA and P(MA-EG) reduced the peak value of hydration exothermic rate by 77.45% and 62.28%, respectively, and prolonged 54.14 h and 15.56 h, respectively. Mechanism studies showed that HHCMs containing carboxylic or hydroxyl groups adsorbed on cement particles by Ca2+complexation, while HHCMs containing ester groups hydrolyzed to carboxylic groups in alkaline cement pastes, which hydrolysis rate changed with the hydration temperature of cement-based materials to regulate the hydration process. This study aims to provide technical feasibility and theoretical basis for exploring new avenues of synthesizing HHCMs with different functional groups.

One problem associated with the operation of electric vehicles (EVs) is the limited battery, which cannot guarantee their endurance. The increasing electricity consumption will also impose a burden on economy and ecology of the vehicles. To achieve energy saving, this paper proposes an adaptive eco-driving method in the environment of signalized corridors. The framework with adaptive and real-time control is implemented by the reinforcement learning technique. First, the operation of EVs in the proximity of intersections is defined as a Markov Decision Process (MDP) to apply the twin delayed deep deterministic policy gradient (TD3) algorithm, to deal with the decision process with continuous action space. Therefore, the speed of the vehicle can be adjusted continuously. Second, safety, traffic mobility, energy consumption, and comfort are all considered by designing a comprehensive reward function for the MDP. Third, the simulation study takes Aoti Street in Nanjing City with several consecutive signalized intersections as the research road network, and the state representation in MDP considers the information from consecutive downstream traffic signals. After the parameter tuning procedure, simulations are carried out for three typical eco-driving scenarios, including free flow, car following, and congestion flow. By comparing with default car-following behavior in the simulation platform SUMO and several state-of-the-art deep reinforcement learning algorithms, the proposed strategy shows a balanced and stable performance.

It is unclear whether the utilisation of fly ash as valuable resource is preferable to landfill disposal from the resource perspective. The objective of this study was to evaluate and compare the resource consumption of fly ash utilisation in a cement clinker system compared to landfill disposal. The results indicated that when fly ash is used as substitute for clay, resource-saving potential of clinker system reached 147.47 MJ/t-clinker. The comparative analysis displayed that exergy-based resource consumption is reduced by 2,020.48 MJ when 1 t fly ash used in a clinker system instead of landfill.

Background: MiR-493 promotes the proliferation of prostate cancer (PC) cells by targeting PHLPP2. We aimed to explore the relationship between miR-493 and autophagy in PC. Methods: qRT-PCR and western blotting were used to determine the mRNA levels and protein expression of miR-493, PHLPP2, autophagy gene BECN1 and ATG7 in PC cells. The autophagy gene expression was determined after PC cells transfected with miR-493 precursor or PHLPP2 precursor. Corresponding changes of autophagy phenotype and PC cell function were also studied. Results: The mRNA levels and protein expression of miR-493, PHLPP2, BECN1 and ATG7 in PC cells were significantly decreased in PC cells. Overexpression of miR-493 or PHLPP2 markedly upregulated the expression levels of BECN1 and ATG7 in PC cells. Overexpression of miR-493 and PHLPP2 markedly promoted autophagy, and inhibited the invasion and cloning formation of PC cells. Conclusion: MiR-493 is a potent inducer of cytotoxic autophagy that leads to prostate cancer inhibition by regulating on PHLPP2.

To improve the resource level of agricultural and forestry waste straws and fallen leaves, straw and fallen leaves fibres were used as organic thermal insulation components (TICs). Vitrified beads and closed-pore expanded perlite were used as inorganic TICs to prepare plant fibre cement-based composite thermal insulation mortar (TIM). The effects of TICs on physical and mechanical properties of TIM were studied by altering the types and contents of TICs. The results show that the fluidity of the TIM decreases with the incorporation of plant fibres in the vitrified bead + expanded perlite TIM. With the addition of wheat straw fibre and straw fibre, the homogeneity of TIM mixture is improved. Plant fibres have the characteristics of lightweight, porosity, water absorption and heat preservation, which increases water absorption and heat retention and a decrease in strength of the TIM. With the incorporation of three plant fibres of leaves, wheat straw and straw, the water absorption of TIM increased by 15.84, 5.47, and 4.54% respectively. At the same time, thermal conductivity decreased by 0.17, 0.19, and 0.20 W/(m.K), respectively, flexural strength decreased by 3.99, 2.63, and 2.44 MPa, and compressive strength decreased by 20.91, 17.13, and 19.25 MPa, respectively. After the expanded perlite and vitrified microbeads are modified with pure acrylic emulsion, the polymer film retains more pores inside the fibres, enhances the interface bonding with the cement-based material, which is helpful to improve the thermal insulation properties and strength of the TIM.

This study aims to achieve further progress in application performance of polymers in cement-based materials. The objective is to establish the research direction of superplasticizers with ordered micro-sequence via the innovation of synthesis technology and to clarify the correlation between the specific motifs in the microstructures of superplasticizers and the properties of cement pastes. In this study, a novel comb-like polycarboxylate superplasticizer (PCE) was synthesized using isobutenyl polyethylene glycol (IPEG) and hydroxyethyl acrylate (HEA) by atom transfer radical polymerization (ATRP) (defined as A-CPCE). Comb-like PCE with the same molecular weight as A-CPCE was also produced via conventional free radical polymerization (defined as CPCE). The molecular properties of both polymers and the structural motifs of monomers therein were characterized via size exclusion chromatography (SEC), 1H nuclear magnetic resonance (1H NMR), 13C nuclear magnetic resonance (13C NMR) and MATLAB, and furthermore the adsorption behavior of PCE polymers on cement particles was analyzed. Together with the rheological and mechanical properties of cement-based materials, the relationship between micro-sequence distribution and macro-performance of PCEs was investigated. The results showed that the monomer sequence distribution in A-CPCE was AAE and AAA, and the probability of the acid-ether ratio of 4:1 was 16.54%, meaning that relatively uniform polymer species were obtained. The A-CPCE molecules exhibited the smaller hydrodynamic radius (Rh=11.7 nm) and stronger adsorption capacity (maximum was 2.3618 mg·g−1) in cement pastes, which was in good accordance with Langmuir isotherm model and pseudo-second order kinetic model. The dispersing power of PCEs correlated with the specific motifs in the microstructures, thus indicating that A-CPCE enhanced the rheological performances of cement paste and concrete. In addition, the compressive strengths of concrete containing A-CPCE after 3 d, 7 d and 28 d were 16.00 MPa, 28.30 MPa and 52.9 MPa, respectively, which were significantly higher than those of concrete with CPCE.

The flat sheet PTFE membrane was modified into hydrophilicity via deposition of fluorinated cationic surfactant. The anti-fouling property of the membranes was investigated using lysozyme (LYS) and humic acid (HA) as typical foulants and further evaluated by Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory. The results indicated that the wettability of the PTFE membrane can be manipulated by concentration of surfactant solution, and the super hydrophilic membrane with water contact angle of 2.1° was obtained with 0.8 wt% of surfactant solution. The super hydrophilic PTFE membrane showed highest cleaning efficiency of 62.5% and better anti-fouling property. XDLVO analysis further suggested that the super hydrophilic PTFE membrane had the strong repulsion force to HA and LYS and displayed better anti-fouling property due to the highest positive total interaction energy (ΔGTOT) value. Linearly fitting on membrane practical fouling process and XDLVO results proved the consistency of the XDLVO theory with the practical anti-fouling process.

Hydraulic lime has been successfully applied to repair masonry/geotechnical ancient architecture. However, chemical pollutants caused by modern industrial development have enriched the building base for a long time, and the mechanism by which corrosive media destroy the hydraulic lime repair material is unclear. In this study, the properties and structural failure of natural hydraulic lime (NHL) and metakaolin-air lime (MK-AL) due to NaOH, NaCl and Na2SO4erosion were studied in terms of macroscopic variation, mechanical property deterioration and internal three-dimensional (3D) structure evolution. The results obtained by XRD, TG-DTA and MIP tests show that the hardening products and pore structure composition of NHL and MK20AL pastes were significantly different, which led to different erosion resistances. Based on the apparent morphology and X-CT test, no cracks were formed in the macroscopic structure of NHL and MK20AL mortar by NaOH and NaCl erosion after different periods. The mechanical strength of NHL mortar showed little change after erosion by the above two media. For the MK20AL mortar, the compressive strength increased by NaOH erosion and the flexural strength decreased significantly by NaCl erosion. No clear expansion cracks formed in the surface and internal structure of NHL mortar by Na2SO4erosion, and the compressive strength increased by ∼20%. Gypsum erosion and secondary erosion (gypsum and C-A-H reaction to generate ettringite) formed in MK20AL mortar by a Na2SO4medium. Additionally, volume expansion of solid phase (corrosion product) caused crack to form in the internal mortar structure, the cracks gradually became wider, and a crack network formed with the extension of erosion; thus, the internal structure and mechanical properties were seriously damaged. Overall, compared to the MK20AL mortar, the NHL mortar shows better resistance to erosion by environmental media, and NHL is the better choice for restoring ancient buildings and plastering mortar projects. The resistance of MK20AL to erosion by mortar environmental media needs to be optimized and modified.

Certain clays attached around the aggregates contaminate the concrete and also greatly affect the concrete workability, the mechanism of which was investigated through calculating the volume change of solid and liquid phases of concrete mixture containing clay. To minimize this detrimental effect, two novel designs based on the transfer of theory and techniques from polymer science, i.e., molecular design of polycarboxylate superplasticizer (PCE), were proposed. The one was “intercalator” synthesized via Hofmann rearrangement and cationization, and the other was “star-shaped polycarboxylate superplasticizer (SPCE)” synthesized via a route of “core first and arm second”. The results of Infrared Spectroscopy (IR) and 1 H Nuclear Magnetic Resonance ( 1 H NMR) confirm the designed structures. The applications of these polymers in clay-contaminated cement paste and concrete were tested. The results showed that, the dispersing capacities of “Intercalator + Comb-shaped polycarboxylate superplasticizer (CPCE)” and SPCE were less affected by adding clay in both cement paste and concrete. Adsorption and X-ray diffraction (XRD) experiments revealed less harmful intercalation for SPCE and preferential occupation in the interlayer space of clay for intercalator to protect other workable PCEs. It is interesting that optimizing charge characteristic and “disassembling-assembling” molecular arrangement can contribute to excellent resistance towards clay. The aim of this study is to offer two promising alternatives, which attractively provide the theoretical basis and technological application in researching advanced materials in clay-contaminated concrete. [ABSTRACT FROM AUTHOR]

The hierarchical-structured superhydrophilic poly(ethylenimine)/poly(acrylic acid) (PEI/PAA)calcium silicate hydrate (CSH) multilayered membranes (PEI/PAA-CSH)nwere prepared as aqueous nanofiltration (NF) membrane, and then they were transformed into superhydrophobic organic solvent nanofiltration (OSN) membranes by one-step modification of trimethylperfluorinatedsilane (PFTS). Investigation on surface structures and properties of these multilayered membranes (PEI/PAA-CSH)nindicated that the hierarchical-structured (PEI/PAA-CSH)nmultilayered membrane produced by in situ incorporation of CSH aggregates into PEI/PAA multilayers facilitated its one-step transformation from superhydrophilicity into superhydrophobicity. Both of the superwetting membranes showed better nanofiltration performances for retention of dyes of water and ethanol solution, respectively. Moreover, the long-term performance and antifouling behaviors, investigated by retention of methyl blue (MB), bovine serum albumin (BSA), and humic acid (HA) aqueous water solution and nonaqueous ethanol solution indicated that both of the superhydrophilic and superhydrophobic membrane showed higher stability and excellent antifouling property.

Three-dimensional Ce-doped ZnO was synthesized via coprecipitation and roasting processes. The samples were characterized by X-ray diffraction, scanning electron microscopy, specific surface area (Brunauer–Emmett–Teller method), and photoluminescence spectra. Also, the photocatalytic activities of ZnO and Ce-doped ZnO were investigated in ultraviolet light for degradation of methylene blue solution. The results indicated that the concentration of NaOH and the doping amount of Ce showed great influence on morphology, structures, and properties of Ce-doped ZnO. When the (Ce3++Zn2+)/OH−was 1:2.5 and the concentration of Ce was 2 mol%, the morphology of the Ce-doped ZnO was microspheres with superstructures assembled by large amounts of interleaving nanosheets. The morphology transformed from microspheres with superstructures to amorphous by changing the ratio of (Ce3++Zn2+)/OH−from 1:2 to 1:3. The photoluminescence spectra indicated that the recombination rate of photogenerated electron–hole pairs of Ce-doped ZnO was suppressed. The prepared Ce-doped ZnO showed much enhanced photocatalytic property than pure ZnO. When the doping concentration of Ce was 2 mol%, the Ce-doped ZnO photocatalysts showed best photocatalytic activity with 99.10% degradation of methylene blue solution after 2 h.

To solve the poor fireproof performance of plant fibers, one of the technical difficulties, and use more straw fibers as construction materials, wheat straw fibers (WSFs) have been subject to flame-retardant modification. Then, tests and analysis over the modified WSFs per the burning behavior and pyrolysis performance have been made. The physical and mechanical, and thermal insulation properties of wheat straw fiber cement-based composites (WSFCC) at high temperatures were characterized. The results are as follows: Ammonium polyphosphate (APP), magnesium hydroxide (MH), and aluminum hydroxide (ATH), three fire retardants, all affect the chemical structure of WSFs. P, Mg, and Al elements of the three retardants are successfully adsorbed onto the fibers' surface subject to modification. Flame-retardant WSFs significantly outperforms the non-flame-retardant ones per thermostability and flame retardancy. The heat release rate (HRR), total heat release (THR), effective heat of combustion (EHC), and mass loss rate (MLR) of most flame-retardant WSFs are obviously lower than those of non-flame-retardant ones. The APP-modified WSFs demonstrate higher total smoke production (TSP), while WSFs modified with composite flame retardants perform better in flame retardancy and smoke suppression. The MLR of WSFCC at high-temperature increases as the temperature goes higher. The compressive and flexural strengths of WSFCC decrease with the increase of temperature and the decrease mitigates after 350°C. In terms of thermal conductivity, composite-flame-retardant fiber WSFCC are much higher than non-flame-retardant fiber and APP-modified fiber WSFCC. As the temperature rises, the thermal conductivity of composite-flame-retardant fiber WSFCC tends to decrease.

The influence of ultrasonic and three types of chemical surfactants (including cationic surfactants: CTAB, anionic surfactants: SDS, and nonionic surfactants: TX-405) on the dispersion of CNTs was investigated. The techniques include UV-Vis-NIR spectrophotometer, laser particle size analyser and scanning electrical microscope (SEM). The results show that: 1) Ultrasonic leads to a dispersive effect on CNTs in water, and the optimal ultrasonic time is 120 s; 2) Three types of surfactants have positive effects on the dispersion of CNTs in water, among which cationic surfactant (CATB) leads to the best dispersibility; 3) CNTs with more carboxyl groups show better dispersion in water indicated from UV-vis-NIR spectra and particle size measurement; 4) The optimum concentration of surfactants is 5:1 (the mass ratio of dispersant to CNTs); 5) Three types of surfactants can improve the dispersion of CNTs in cement pastes indicated from SEM images at the optimum dosage.