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Nonskeletal animals such as worms achieve locomotion via crawling. We consider them as an inspiration to design robots that help underline the mechanisms of crawling. In this paper, we aim to identify an approach with the simplest structure and actuators. Our robots consist of cut-and-fold bodies equipped with pneumatically-driven soft actuators. We have developed fabrication techniques for coin-sized robots. Experiments showed that our robots can move up to 4.5 mm/s with straight motion (i.e., 0.1 body lengths per second) and perform cornering and U-turns. We have also studied the friction characteristics of our robots with the ground to develop a multistate model with stick–slip contact conversions. Our theoretical analyses depict comparable results to experiments demonstrating that simple and straightforward techniques can illustrate the crawling mechanism. Considering the minimal robots' structure, this result is a critical step towards developing miniature crawling robots successfully. [ABSTRACT FROM AUTHOR]

A comprehensive recovery process for the selective separation and enrichment of copper, zinc and iron minerals from a polymetallic ore was developed, which consisted of copper flotation, zinc flotation, and iron magnetic separation, and the adsorption mechanism of the copper collector Z-200 (O-isopropyl-N-ethyl thionocarbamate) was also studied in this work. The contents of the main valuable metallic elements of Cu, Zn and Fe in the ore were respectively 0.61%, 1.68% and 14.17%, and they mainly existed as chalcopyrite, sphalerite and magnetite, whose dissemination relationship was complex. Under the optimal conditions of this process, the recoveries of Cu, Zn and Fe in their respective concentrates reached 86.1%, 87.6% and 77.8%, and their grades were separately 20.31%, 45.97% and 63.39%. This process realized the selective separation and beneficiation of copper, zinc, and iron minerals from the ore, and had promising industrial application prospects. The adsorption configuration analysis demonstrated that the steadiest adsorption configurations of Z-200 on the surfaces of chalcopyrite, sphalerite and magnetite were the simultaneous adsorption of carbonyl S together with the O atom. Compared with sphalerite and magnetite, Z-200 was more prone to adsorb on the chalcopyrite surface. The Mulliken charge population and bond length analyses manifested that Z-200 chemically adsorbed on the chalcopyrite surface by forming a normal covalent bond and a back donation covalent bond, and the normal covalent bond played a leading role. The chemisorption of Z-00 was supported by the FTIR spectrum analysis result. [ABSTRACT FROM AUTHOR]

Preparation of biological scaffolds with complex shapes and controllable internal structures is a significant development direction for the tissue engineering field. Due to its simplicity, low‐cost and cost‐effectiveness, fused deposition molding (FDM) is one of the most popular 3D printing technologies. In this paper, polyvinyl alcohol/polylactic acid/hydroxyapatite composites were fabricated successfully. On this basis, composite scaffolds with different pore structures were designed and constructed by using FDM technology. The material structure was characterized by scanning electron microscopy (SEM) and dynamic thermomechanical analyzer. The results showed that the cross‐sectional morphology of the system presented a "sea‐island" structure. The introduction of PLA and HA significantly increased the modulus of the material, which was beneficial to achieve its FDM processing. The compressibility, mineralization behavior, and biocompatibility of the viscoelastic characteristics to natural cartilage subjected to the condition of filling angle of 45° was systemically invesitgated. Notably, the concentrations of Ca2+ and PO43− in simulated body fluid were reduced by 34.7% and 58.2% on 8th day, indicating a good bone formation and mineralization ability, which was further corroborated by SEM and fourier‐transform infrared spectroscopy (FTIR) results. Biotoxicity test showed that the scaffold presented excellent biocompatibility. [ABSTRACT FROM AUTHOR]

Poly(vinyl alcohol)/hydroxyapatite (PVA/HA) has excellent mechanical properties and osteoconductivity that allow it to be used for cartilage repair. However, nanofillers, such as HA, cause PVA to foam during the extrusion process, making it difficult to produce filament feedstocks with uniform diameters that are suitable for fused deposition modeling (FDM). In this article, a novel method was developed to prevent the foaming of PVA‐based nanocomposites during extrusion by selectively distributing HA in the poly(lactic acid) (PLA) phase. To achieve this, HA was treated with 3‐Glycidoxypropyltrimethoxysilane (KH560). The results showed that HA treated with KH560 was segregated from the PVA phase, thus preventing the foaming of PVA. Finally, filament feedstocks with a uniform diameter of 1.75 ± 0.05 mm, which is suitable for FDM, were successfully fabricated. Meanwhile, a mathematical equation for characterizing the printability of feedstock materials was improved. The results indicated that in combination with PLA, composites with a higher compressive modulus and better melt flowability were able to be processed by FDM. Finally, complex PVA‐based bioactive nanocomposite scaffolds with high dimensional accuracy, good mechanical properties, and biocompatibility were fabricated by the FDM machine. POLYM. COMPOS., 39:E508–E518, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

The low Li + transport and poor interface have consistently been two major impediments to practical applications of Polyacrylonitrile (PAN)-based composite solid-state electrolytes (PCPE). In this work, a polymerizable deep eutectic electrolyte is meticulously designed with high fluidity which consists of Poly (Ethylene Glycol) Diacrylate (PEGDA), Fluoroethylene Carbonate (FEC), Succinonitrile (SN) and dual salts (LiTFSI/LiDFOB) to promote Li + transport and ameliorate the interface of PCPE. Inclusion of PEGDA monomers and FEC alters the crystallinity of SN, enhancing the wettability of thick electrode, and formation of polymeric 3D network from polymerization of PEGDA can anchor SN and suppress the side reactions between SN and lithium metal. Consequently, the modified PCPE exhibit an enhanced conductivity of 4.47 × 10 -4  S cm -1 with Li-ion transference number of 0.60, and show an excellent lithium stability. LiCoO 2 (LCO)/SP-PCPE/Li batteries with higher loading (3-4.4 V, 6 mg cm -2 ) can work for over 300 cycles at 0.5 C. Even with an ultra-high loading of 16 mg cm -2 , LCO/SP-PCPE/Li batteries achieve an excellent cycling performance. This work provides new insights into how to construct a robust interface for solid-state batteries with high-loading cathode., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)