A new 3D coordination polymer was solvothermally synthesized. The coordination polymer possesses a lon network built from 4-connecting Co 2 clusters and tetracarboxylate ligands, and exhibits selective gas sorption behavior as well as antiferromagnetic interactions.Crystal engineering provides a powerful tool for the construction of metal-organic frameworks (MOFs). 1,2 Various organic ligands and secondary building units have been specifically designed for the synthesis of MOFs with desirable characteristics (gas storage/ separation, 3 photoactive material, 4 magnetism, 5 catalysis, 6 etc.). In particular, MOFs which have novel topologies and special applications attract the most attention. With the fundamental contributions by A. F. Wells, M. O'Keeffe and R. Robson, 7 great efforts have been devoted to design and understand the network structure/topology of MOFs. Up to now, a large number of MOFs have been reported, while the large majority of 3-D MOFs with uninodal nets usually possess low connected structural topology and are dominated by the 4-connected nodes 6a,7 such as diamond (dia), SrAl 2 (sra), quartz (qtz), square (sql), NbO (nbo), CdSO 4 (cds), and PtS (pts) net. From both zeolite chemistry and crystal engineering points of view, the frameworks built from 4-connected tetrahedral centers can generate larger cavities and bigger access windows than those based on octahedral centers and might result in 3D porous frameworks with a low framework density. So there has been increasing interest in the use of tetrahedral fourconnected centers as basic structural units for the construction of open-framework materials. For tetrahedral nodes, two types of topologies are possible, namely, diamond (dia) and lonsdaleite (lon) nets. 8 Although the two structures are composed of fused 6-membered rings, all such rings in diamond have the chair conformation while those in the lonsdaleite assume both chair and boat conformations. As the natural choice for porous material, the topology of dia networks is noticeably classic and widely reported in MOFs, whereas the lon network is still very difficult to realize in MOFs: this remains a great challenge. 9 Meanwhile, surface modification is a useful tool for introducing new functionalities for MOFs and received much attention.Recently several MOFs have been constructed with amide decorated multiple carboxylate ligands, 10 which are proved to have guest-accessible functional amide sites in the channel and some materials show high CO 2 adsorption capacities due to these functional groups. 11 Given the above concerns, we prepared a new ligand containing four carboxylate groups as coordination sites and four amide groups as functional sites (bis-(3,5-dicarboxy-pheny1) terephthalamide, H 4 L Scheme 1). We expected that the amide groups might influence the gas sorption properties. Herein we report the synthesis and characterization of {[Co 2 (L)(H 2 O) 3 ]?S x } n (S is either DMF or water molecule and x is number of solvent molecules in the crystal) with a rare lon topology based ...

A simple and efficient chemical method was developed to graft directly carbon nanofibers (CNFs) onto carbon fiber (CF) surface to construct a CF‐CNF hierarchical reinforcing structure. The grafted CF reinforcements via covalent ester linkage at low temperature without any usage of dendrimer or catalyst was investigated by FTIR, X‐ray photoelectron spectroscopy, Raman, scanning electron microscopy, atomic force microscopy, dynamic contact angle analysis, and single fiber tensile testing. The results indicated that the CNFs with high density could effectively increase the polarity, wettability, and roughness of the CF surface. Simultaneous enhancements of the interfacial shear strength, flexural strength, and dynamic mechanical properties as well as the tensile strength of CFs were achieved, for an increase of 75.8%, 21.9%, 21.7%, and 0.5%, respectively. We believe the facile and effective method may provide a novel and promising interface design strategy for next‐generation advanced composite structures.

Hyperbranched polymer with terminal hydroxyl groups (HBPH) was grafted successfully onto carbon fiber (CFs) surface in two‐step polycondensation to improve the interfacial properties of CFs‐reinforced epoxy resin composites. The microstructure and interfacial properties of CFs before and after modification were investigated systematically. Experimental results indicated that HBPH were grafted uniformly onto CFs using γ‐aminopropyltriethoxysilane as the coupling agent. The polarity, roughness and wettability of the grafted fiber (CF‐HBPH) were enhanced distinctly in comparison with those of untreated CF. The CF‐HBPH composites displayed remarkable enhancement in interfacial shear strength, flexural strength and modulus (52.9, 29.1, and 42.6%) with no deteriorating fiber tensile strength, which was ascribed to the augment in fiber–epoxy interface through improved chemical interactions and mechanical interlocking. This was in accordance with scanning electron microscopy observations from the fracture surface morphologies of the composites. POLYM. COMPOS., 40:E1378–E1387, 2019. © 2018 Society of Plastics Engineers

A 90-day study was performed under three different stocking densities, including high density (10,000 fishes/cage), medium density (8000 fishes/cage), and low density (6000 fishes/cage), in a deep-sea net cage for yellowtail kingfish (Seriola lalandi). The physiological characteristics and growth performance were tested, and structural characteristics of the gastrointestinal microbiota were systematically analyzed. The results show that fishes with high density had a lower weight gain rate and a specific growth rate, as well as higher serum cortisol content. The diversity, types and numbers of dominant microbiota with significant differences, and the numbers of shared genera among the different groups all changed. Core genera in the gastrointestinal tract were obtained according to the principles of dominance, commonality, and difference. The changes in the relative abundance of the core genera might be related to the growth and physiological characteristics of the host. The ratio of Firmicutes to Bacteroidetes in the stomach and pyloric caecum, which favors the accumulation of energy by the host from the diet, was higher in the medium-density group than in the other groups. This indicates that the higher density could cause physiological stress and affect growth performance. In order to reduce the resulting growth differences, gastrointestinal microbiota might assist the host in accumulating energy, participating in the energy distribution by adjusting its structure. Based on the growth, physiology, and production practices, the medium density was the appropriate density in this study. This study provides a reference for the improvement of deep-sea culture technology and the promotion of healthy growth through the gastrointestinal microecological regulation of yellowtail kingfish.

was constructed based on a honeycomb coordination subunit with both octahedral and tetrahedral Co II sites, showing moderate MeOH sorption and antiferromagnetic properties.