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Aluminum alloy is widely used in many fields for its excellent performance. However, in practical application, aluminum alloy is easy to become corroded and be invalidated, owing to the influence of environmental factors. Some pollutants or corrosive media on its surface adhesion will further deepen the failure rate of aluminum alloy, resulting in a large amount of workforce waste, waste of material and financial resources, and energy consumption. So the anti-corrosion and anti-fouling treatment of aluminum alloy surfaces to expand their practical application range and reduce energy loss are of great significance. In this paper, we first summarize the types of anti-corrosion and anti-fouling coatings on aluminum alloy surfaces. We found that superhydrophobic coating has attracted widespread attention recently because of its surface's non-wetting and low surface energy characteristics. The superhydrophobic coating refers to a coating with a water contact angle on its surface greater than 150° and a sliding angle of less than 10°. Preparing superhydrophobic coatings on the surface of aluminum alloy can improve the corrosion resistance and anti-pollutant adhesion ability at the same time. Therefore, in the following part of the review, the preparation methods of superhydrophobic coatings on aluminum alloy surfaces for anti-corrosion and anti-fouling and the significant problems encountered in the practical application of the superhydrophobic coating on aluminum alloy surfaces, such as poor anti-corrosion durability and poor mechanical stability, and the existing methods to solve these critical problems, are summarized and discussed in detail. Finally, we put forward some new solutions to solve these vital issues. [ABSTRACT FROM AUTHOR]

An important force for participation in urban and rural infrastructure transformation (URIT) is private capital (PC), which helps to emphasize the importance of government departments in effectively implementing quality urban development strategies when driving PC in order to participate in URIT in a compliant and efficient manner. This article constructs a system of factors that influence the participation of PC in URIT, which uses the analytical hierarchy process–criteria importance through inter-criteria correlation (AHP-CRITIC) combination method to quantify the comprehensive assignment of influencing factors, in order to analyze the poor effectiveness of PC participation in URIT. On this basis, combined with a logical mechanism analysis of PC participation in URIT, the evolutionary system dynamics model was constructed, and it concerned the correlation between PC's willingness to participate in URIT and PC's willingness to participate in each of the influencing factors. The results of the study show that (1) factors such as "return on project investment", "tax breaks", "level of government finance", "project construction cost", "mechanism for public selection of PC", and "establishment of a special coordinating department" are the most influential factors concerning the willingness of PC to participate in URIT; (2) the "open selection of PC" and the "establishment of a coordinating department" at the level of government behavior, and "tax relief" at the level of the policy system, directly affect the willingness of PC to participate in URIT; and (3) the analysis is based on the model simulation results, combined with stakeholder theory and incentive theory. After analyzing the simulation results, it was observed that increasing the degree of implementation, regarding the "public selection of PC" and "establishment of coordination departments" among the influencing factors related to the government's behavior, significantly enhanced the willingness of PC to participate during the final stage of the simulation. The willingness increased from 2.81 to 3.24 and 3.22, respectively. Furthermore, after doubling the "tax relief" within the policy system, the willingness of PC to participate increased from 2.81 to 3.05 during the final simulation. Finally, this article gives strategic recommendations as to how governments can incentivize PC participation in URIT, which mainly include strengthening the profitability of URIT projects, innovating the PC participation model, improving the completeness of the supporting policies, and strengthening the co-ordination of local policies. The theoretical models and research results presented in this article can provide a reference for government policy makers to encourage PC participation in URIT and provide new ideas for transformation methods concerning PC participation in URIT. [ABSTRACT FROM AUTHOR]

In this work, we engineered a corn-straw-based bio-foam material under the inspiration of the intrinsic morphology of the corn stem. The explosion pretreatment was applied to obtain a fibrillated cellulose starting material rich in lignin. The in situ esterification of cellulose was adopted to improve the cross-linking network of the as-developed foam bio-material. The esterification of lignin was observed in the same procedure, which provides a better cross-linking interaction. The esterified corn-straw-derived bio-foam material showed excellent elastic resilience performance with an elastic recovery ratio of 83% and an elastic modulus of 20 kPa. Meanwhile, with surface modification by hexachlorocyclotriphosphazene-functionalized lignin as the flame retardant (Lig-HCCP), the as-obtained bio-foam material demonstrated quite a good flame retardancy (with 27.3% of the LOI), as well as a heat insulation property. The corn-straw-derived bio-foam material is prospected to be a potential substitution packaging material for widely used petroleum-derived products. This work provides a new value-added application of the abundant agricultural straw biomass resources. [ABSTRACT FROM AUTHOR]

Recycled concrete, which is formed by replacing coarse aggregates in ordinary concrete with recycled aggregates (RA), is of great significance for the secondary utilization of waste building resources. In civil engineering, concrete structures are sometimes subjected to a compression–shear multiaxial stress state. Therefore, research on the compression–shear multiaxial mechanical properties of recycled concrete plays an important role in engineering practice. To explore the effect of RA replacement rate on the compression–shear properties of recycled concrete, an experimental study was carried out using a compression–shear testing machine and considering five RA replacement rates and five axial compression ratios. Consequently, the failure modes and mechanical property parameters under different working conditions were obtained and were used to analyze the effects of RA replacement rate and axial compression ratio on the shear stress of recycled concrete. Eventually, the following conclusions were reached: With the growth of axial compression ratio, the shear cracks exhibit a developing trend along the oblique direction, and the friction traces on the shear surface are gradually deepened. As the replacement rate increases, the number of shear cracks is gradually increased, accompanied by increasing broken fragments falling off from the shear interface. Since the action of the axial compression ratio can effectively improve the mechanical bite force and friction on the shear interface of recycled concrete, as the axial compression ratio increases, the shear stress is gradually increased. On the other hand, due to the initial damage of RA and its weak adhesion with cement mortar, the shear stress is gradually reduced with the increase of RA replacement rate. Meanwhile, the increase in shear stress shows a gradually decreasing trend with the growth of axial compression ratio. Specifically, for the RA replacement rates of 0% and 100%, the shear stress increased by 4.06 times and 3.21 times, respectively, under the influence of the axial compression ratio. Under different axial compression ratios, the shear stress was reduced by 43~46%, due to the increase of RA replacement rate. In addition, based on the octahedral stress space and the principal stress space, a compression–shear multiaxial failure criterion and shear stress calculation model for recycled concrete were proposed, by considering the effect of the RA replacement rate. The outcomes of this research are of great significance for engineering applications and the development of recycled concrete. [ABSTRACT FROM AUTHOR]

To investigate the dynamic compressive properties of concrete after high temperature and rapid cooling, an experimental study was carried out by considering five temperatures and four strain rates. The coupling effect of high temperature and strain rate on concrete damage morphology and mechanical parameters was comparatively analyzed. The main conclusions are as follows: the compressive damage morphology of concrete is affected by strain rate development trends of significant variability under different temperature conditions. As the strain rate increases, the compressive stress and elastic modulus of concrete are gradually increased. As the temperature increases, the increase in compressive stress is gradually reduced by the strain rate. For the temperatures of 20 °C and 800 °C, the increase in compressive stress by the strain rate is 38.69% and 7.78%, respectively. Meanwhile, SEM and CT scanning technology were applied to examine the mechanism of the effect of high temperature and strain rate on the mechanical properties of concrete from the microscopic perspective, and the corresponding constitutive model was proposed. [ABSTRACT FROM AUTHOR]

Methionine (Met) was introduced to modify the Li-Al layered double hydroxides (LDHs) film prepared on 6063 aluminum alloy by in situ method for the first time. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, Scanning electron microscopy, and X-ray diffraction confirmed the successful insertion of Met into LDHs film and revealed that the introduction of Met could make the LDHs film much denser. Electrochemical tests illustrated that the corrosion rate of the Met modified LDHs film was reduced by more than an order of magnitude compared with the bare Al alloy. Moreover, the corrosion rate of the modified LDHs film after immersion in 3.5 wt.% NaCl solution for 21 days was almost the same as that without immersion, which indicates that the modified film has good corrosion durability. The corrosion resistance of the scratched modified film could recover to the level without a scratch on the 14th day based on the scratch test results, meaning the modified film has a good self-healing property. Finally, the anti-corrosion mechanism of the Met was proved by molecular dynamic simulations and found that the enhanced corrosion resistance may be attributed to the addition of Met that slowed the diffusion of the corrosive medium Cl− and water molecules. [ABSTRACT FROM AUTHOR]

The co-delivery of chemotherapeutic agents and immune modulators to their targets remains to be a great challenge for nanocarriers. Here, we developed a hybrid thermosensitive nanoparticle (TMNP) which could co-deliver paclitaxel-loaded transferrin (PTX@TF) and marimastat-loaded thermosensitive liposomes (MMST/LTSLs) for the dual targeting of cancer cells and the microenvironment. TMNPs could rapidly release the two payloads triggered by the hyperthermia treatment at the site of tumor. The released PTX@TF entered cancer cells via transferrin-receptor-mediated endocytosis and inhibited the survival of tumor cells. MMST was intelligently employed as an immunomodulator to improve immunotherapy by inhibiting matrix metalloproteinases to reduce chemokine degradation and recruit T cells. The TMNPs promoted the tumor infiltration of CD3+ T cells by 2-fold, including memory/effector CD8+ T cells (4.2-fold) and CD4+ (1.7-fold), but not regulatory T cells. Our in vivo anti-tumor experiment suggested that TMNPs possessed the highest tumor growth inhibitory rate (80.86%) compared with the control group. We demonstrated that the nanoplatform could effectively inhibit the growth of tumors and enhance T cell recruitment through the co-delivery of paclitaxel and marimastat, which could be a promising strategy for the combination of chemotherapy and immunotherapy for cancer treatment.