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Aerogels with tailored geometric features and improved mechanical properties are urgently needed for thermal insulation applications in specific scenarios. However, traditional manufacturing strategies show limitations in the on-demand shaping of aerogels due to their costly and time-consuming fabrication cycles and poor serious impediment fragility. Herein, the ultraviolet (UV)-assisted extrusion printing strategy has been adopted to fabricate photosensitive resin-crosslinked silica (PRCS) aerogel composites. During extrusion printing, there is a synergic process of consecutive ink extrusion deposition and instantaneous photopolymerization of photosensitive resins, displaying a considerable characteristic of solidification-while-printing. The successful implementation for the UV-assisted extrusion printing of PRCS aerogel composites depends on the viscoelasticity and photosensitivity of inks, where the viscoelasticity enables inks to smoothly flow from nozzles and the photosensitivity allows inks to solidify rapidly based on the radical polymerization of photosensitive resin monomers. The UV-assisted extrusion printing strategy has a huge capacity for the rapid manufacturing of aerogel geometries without an additional auxiliary support. After supercritical drying, the 3D-printed PRCS aerogel composites exhibit high shape fidelity and comparable aerogel performances, such as low density (0.256 g·cm–3), high specific surface area (269.3 m2·g–1), high pore volume (1.82 cm3·g–1), improved mechanical properties (compressive strength up to 0.28 MPa), and low thermal conductivity (38.41 mW·m–1·K–1). This work would provide more potential for silica aerogels to satisfy the requirements of shape-dominated insulation applications in specific scenarios. [ABSTRACT FROM AUTHOR]

Purpose: To explore the effect of solid waste material and high-sulfur tailings with potential cementing activity around the mine on the strength of cemented backfill and filling slurry,and reveal the excitation mechanism of high-sulfur tailings composite backfill material. Method:Through uniaxial compressive test and SKM/EDS test,the compressive strength, failure mode, and microstructure of backfill samples with different proportions were analyzed. Result;The results show that compared with 100%cement,the 7 d strength of the 3 : 7 or 4 : 6 cemented backfill samples with tailing sand and Gobi aggregate is improved when quicklime is used as the activator. When the proportion of tailing sand and Gobi aggregate is the same, the mechanical strength of cemented backfill gradually decreases with the increase of lime content,and the optimal lime content is 10%. Appropriate increase of slag powder content is conducive to the improvement of mechanical strength. Through microstructure analysis,a large number of fibrous C-S-H and acicular ettringite( Aft) were generated inside the hydration reaction specimen. The main elements in the backfill sample were O, C, Si, Ca, Al, and Mg. Conclusion; It is feasible to replace cement with solid waste. Significance;The research results can provide the theoretical and technical basis for the application of solid waste materials under different requirements of filling technology. [ABSTRACT FROM AUTHOR]

The formal beauty of "objects" is the main focus of modern rural landscapes, ignoring human interaction with the environment and the emotional reflection in this behavioral process. It is unable to satisfy the emotional needs of younger people who aspire to a high-quality life in the rural environment. The research idea of this paper is 'first assessment—then design—then validation'. First, A 5-point Likert scale was used to investigate differences in contemporary young people's emotional perceptions of the four rural natural landscapes in terms of instinct, behavior, and reflection. Then, using architectural design methods, a visual attraction element (viewing platform) was added by selecting samples that varied in all three dimensions (visual richness, behavioral attraction, and depth of thought). After that, a desktop eye tracker was used to record the eyeball characteristics of participants viewing the current images of natural landscapes and images of modified natural landscapes (pupil diameter, fixation duration, gaze point, etc.), and these data were combined with the subjective psychological perception scale score to determine whether or not the subjects' positive emotions are evoked by the modified natural environment. The findings indicate that placing visually attractive elements between people and the natural world can cause subjects to feel good, think deeply, and feel more a part of the surroundings. Furthermore, we confirmed that subjects' emotions can be evoked by 2D natural environment pictures and that the length of time subjects gaze at a picture is unaffected by the size of any individual element. [ABSTRACT FROM AUTHOR]

Abstract Acrylamide (AA) is the potential carcinogen, which can induce multiple toxic effects in laboratory animals and humans. So far, increasing attention have been paid to toxical mechanism and intervention measures of AA, however, these details and methods are still obscure. MicroRNAs (miRNAs) have been demonstrated to be involved in toxical functional mechanisms induced by chemicals in vivo or vitro. To explore novel target and mechanism of AA toxicity, a more detailed miRNA expression profiling study is needed. In this study, we established the short‐term high‐dose model of rats with the treatment of 35 mg/kg·b.w./day AA for 17 days, analyzed the miRNAs expression profiling in AA and control groups, and discovered the altered miRNA profiles in 11 tissues with AA treatment. Interestingly enough, the expression of miR‐27a‐5p were significantly up‐regulated in AA group, especially in bladder and hepar. Furthermore, we found miR‐27a‐5p increased in 11 tissues of long‐term low‐dose AA‐treated rats (3.5 mg/kg·b.w./day for 68 days). Therefore, these results revealed that AA changed miRNAs profiles in multiple tissues of SD rats for the first time and suggested that miR‐27a‐5p could be used as the target biomarker for the detection and interference of AA toxicity.