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Existing auxetic honeycomb meta-structures are generally integrated structures with complicated microstructural geometry which hence should be fabricated by costly additive manufacturing (AM) technology. The high cost and low production efficiency of AM technology is still the main bottleneck restricting the engineering applications of such kind of structures. In this work, a prefabricated auxetic honeycomb meta-structure with modularized components was proposed based on mortise and tenon (M&R) principle originated in ancient China. The modularized components of the prefabricated auxetic honeycomb are all tubular structures which can be easily fabricated by traditional manufacturing with low cost and high technical maturity. The mechanical properties of the proposed meta-structure were then detailed investigated numerically under quasi-static and dynamic loading conditions. The referenced integrated auxetic honeycomb meta-structure was also considered as a benchmark for comparison. Results show that the proposed prefabricated design exhibits lower strength and stiffness compared with its integrated counterpart, owing to the introduction of more flexibility. Consequently, the proposed design processes a much more stable stress plateau stage with a larger deformation range and effectively reduces the reactive force of the protected structure. The present work paves a novel avenue to design protective meta-structures with low-cost and high performance. [ABSTRACT FROM AUTHOR]

Lantern, also known as coloured-lantern making, is known for being an ancient traditional craft in China that can be dated back as early as West Han Dynasty. Inspired by the lantern, the lattice element is built by vertically rotating and duplicating the 2D units, then the 3D auxetic metamaterial is formed by connecting the 8 ligaments of the lattice element on two perpendicular planes. As the elastic behaviors associated with this metamaterial are still almost unknown to a large extent, in this study, an analysis has been conducted to investigate how the geometric parameters related to the lattice design influence its elasticity. For this reason, a novel 3D lantern-shaped honeycomb structure (LSH) has been proposed, the Castigliano's second theorem, energy principle, and Moore's theorem are utilized to solve its Young's modulus and Poisson's ratio in the three main directions. The theoretical results exhibit good agreement with the numerical and experimental results. The results showed that the elasticity of LSH structures can be programmed by adjusting a range of geometric parameters. In addition, LSH features a bidirectional zero Poisson effect and a good stress distribution during compression. It shows potential in terms of load-bearing to meet the requirement of lightweight and high stiffness. This structure shows good promise for applications in aerospace, construction and other fields. [ABSTRACT FROM AUTHOR]

Background: The updated standard classification and pathophysiology of rosacea have provided clear and meaningful evaluation parameters; however, differentiating rosacea from sensitive skin (SS) remained an obstacle for dermatologists around the world, especially in China. Herein, we aimed to find a better characteristic to distinguish rosacea from SS by using reflectance confocal microscopy (RCM). Method: Forty rosacea patients and 143 healthy subjects were recruited in this study. Firstly, a SS questionnaire and a lactic acid sting test were conducted among healthy subjects. Next, two major groups were divided out, including a SS group (40 subjects) and a normal skin control group (NS, 60 subjects). The cutaneous structures of face and fossa cubitalia were imaged by RCM. Results: We found that more parakeratosis, honeycomb pattern, spongiform edema, and dermal papillae (P <.05) in rosacea patients than that of the NS group, whereas there were no significant differences, were found in rosacea patients and the SS group. Strikingly, we found that rosacea patients have a larger depth of honeycomb pattern than that of SS subjects (P <.05). But, the epidermal thickness of rosacea did not differ from that of SS groups. There was also no significant difference of epidermal thickness and honeycomb structure depth between rosacea patients and NS group. Conclusion: From the RCM images of parakeratosis, honeycomb pattern, spongiform edema, and dermal papillae, we found that RCM might be a faithful tool to distinguish rosacea from NS group. The depth of honeycomb structure of SS was more superficial than rosacea patients, whereas no significant difference between rosacea patients and NS group. RCM may provide a new method for evaluating the development of rosacea although it failed to distinguish rosacea and SS effectively. [ABSTRACT FROM AUTHOR]

A honeycomb briquette made from semi-coke and corn stover char was developed as a possible heating fuel in rural China. In this study, the co-combustion characteristics of semi-coke and corn stover char combined in different proportions were tested and analyzed. It was determined that adding 20% corn stover char (BS28) effectively improved the combustion performance of semi-coke, and this proportion was regarded as the ideal mixing ratio. Thus, the integrated combustion characteristics of the blend improved to 15.08 × 10−12 K−3 min−2 compared to 5.44 × 10−12 K−3 min−2 for semi-coke alone. The emission test results revealed that SO 2 and PM 2.5 emissions decreased with corn stover char addition; however, NO X emissions increased and the combustion efficiency decreased slightly with corn stover char addition. The SO 2 concentrations resulting from the combustion of BriqCK, Briq28, and Briq46 (honeycomb briquettes with ratios of char to semi-coke of 0:10, 2:8, and 4:6, respectively) under different experimental conditions were 24.9–26.3, 9.5–16.7, and 5.2–15.4 mg/Nm3, respectively, and the NO X concentrations were 63.1–149.7, 54.3–175.4, and 57.7–168.4 mg/Nm3, respectively. A value-chain model for the new heating fuel was developed and possible benefits were analyzed. If either the new investment cost or raw material input costs ($25 USD/t of straw char) were subsidized by national public finance, then the project would be profitable and run sustainably. This study provided an important technical basis for the development and application of new heating fuels in China. Image 1 • Semi-coke was condensed with corn stover char to produce heating fuel. • Corn stover char improved the integrated combustion characteristics of semi-coke. • SO 2 and PM 2.5 emissions decreased with the addition of corn stover char. • NO X emissions increased slightly with the addition of corn stover char. • A value-chain model for the new heating fuel was designed and analyzed. [ABSTRACT FROM AUTHOR]