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Bone tissue engineering plays an extremely important role in the clinical treatment of bone defects. Porous scaffold is one of the three essential factors of bone tissue engineering, and its structural design has attracted more and more attention. At present, most of the design methods of porous scaffolds focus on uniform porous scaffolds with periodic and regular pore structures. However, periodic and regular pore structure cannot comprehensively and accurately simulate the microstructures and mechanical properties of natural bone. To address this problem, based on bone slice images and VT (Voronoi‐Tessellation) method, this article proposed a design method of HPS (Heterogeneous Porous Scaffolds) with bionic pore structure and controllable porosity. The FDM (fused deposition modeling) printing technology was applied to fabricate HPS with different porosities, and the mechanical properties of the HPS were analyzed by experiments. The research results illustrate that the HPS constructed by the design method proposed in this article have good controllability, and their internal pore structures are highly similar to those of natural bone, which have biomimetic characteristics. The mechanical property analysis illustrate that the stiffness and compressive strength of HPS decrease with the increase of porosity, in addition, the heterogeneous pore distribution makes HPS have the characteristics of non‐concentrated and discontinuous damage distribution. This study provides a new idea for the design of porous scaffolds and a theoretical basis for the bionic design of HPS. [ABSTRACT FROM AUTHOR]

The angle‐of‐attack (AOA) three‐loop feedback autopilot is an improved three‐loop autopilot that has been widely employed in missile control systems. For spinning missiles, however, unstable coning motion can be induced by the cross‐couple effect. For spinning missiles with an AOA feedback autopilot, this paper analyzes the coning motion stability with the consideration of the augmentation loop and the position of the accelerometer and compares the performance of three decoupling methods. First, a novel double‐channel actuator AOA three‐loop autopilot is established, and the sufficient and necessary condition of coning motion stability is proposed analytically on account of the complex system equations. The stability condition shows that the stable region of the design parameters for the autopilot shrinks as a result of the spinning condition. Moreover, methods associated with actuator dynamics, control coupling, static stability, and the decoupling method of setting the lead angle to the control system are presented to improve the stability of spinning missiles. Numerical simulations are implemented to demonstrate the accuracy of the proposed methods, whose results illustrate that the stability conditions can guide AOA autopilot design for the flight stabilization of spinning missiles. [ABSTRACT FROM AUTHOR]

To explore the skin moisturizing performance of aloe viscose fiber seamless knitted fabric, this experiment takes the different yarn-blending ratios of aloe viscose fiber and viscose fiber, as well as three different tissue structures as factors, establishes a sample scheme according to full factor experimental tests on skin hydration and trans epidermal water loss (TEWL) after the sample fabric had been wrapped around the skin, and uses two-way and one-way ANOVA in SPSS and the Duncan multiple comparison method. The test data were analyzed to study the influence of different materials and the structure of the veil on the moisture retention of the fabric. The results show that the sample scheme with the largest change rate of skin hydration is when the raw material of the veil is aloe viscose/viscose 100/0 yarn, and the structure is 1 + 3 simulated rib. The sample scheme with the minimum change rate of TEWL is when aloe viscose/viscose 75/25 yarn is used as the raw material of the veil, and the structure is 1 + 1 simulated rib, which provides a theoretical basis for the research and development of moisturizing knitted fabric. [ABSTRACT FROM AUTHOR]

[Display omitted] • The insertion of pillar ligands of UPC-190 series MOFs can lead to changes in the interpenetrating structure. The degree of interpenetration can be managed by introducing different pillars. • Theoretical calculations demonstrate that the fluorine atom on pillar ligands is an effective interaction site for C 2 H 2 molecules. This means that fluorine atoms can act as active sites that interact with C 2 H 2 molecules, thereby influencing their adsorption behavior. • The formation of interpenetrating structures and the stepwise fluorination strategy gradually improve the IAST selectivity and C 2 H 2 uptake of the sample. This strategy proves guidance for designing MOFs for challenging gas separations. The efficient separation of C 2 H 2 /CO 2 possesses great commercial and research value and remains challenging due to their similar molecular sizes and physical properties. Functionalization is a powerful strategy for precisely regulating the pore environment of porous adsorbents, notably metal–organic frameworks (MOFs), for recognizing target molecules. Here, we construct three interpenetrated MOFs using a stepwise fluorinated pillar-ligand strategy. Interestingly, the degree of interpenetration can be managed by introducing different pillars. The unique interpenetrating structure cooperates with fluorine-rich pore environment significantly improves the C 2 H 2 uptake and the C 2 H 2 /CO 2 separation selectivity. The optimized difluorine-functionalized UPC-193 exhibits the highest C 2 H 2 adsorption capacity (80.45 cm3/g) and separation efficiency (C 2 H 2 /CO 2 uptake ratio of 1.9) among UPC-190 systems at ambient conditions. Ideal adsorbed solution theory (IAST) calculations, molecular modeling studies, and breakthrough experiments comprehensively demonstrate that UPC-193 is an effective MOF adsorbent for equimolar C 2 H 2 /CO 2 separation. The stepwise pillar-ligand fluorination strategy proves to be an effective approach to extend the functionality of MOFs for challenging gas separations. [ABSTRACT FROM AUTHOR]