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Binary transition metal selenides (BTMSs) are more promising than single transition metal selenides (TMS) as anode materials of sodium-ion batteries (SIBs). However, it is still very challenging to prepare high-performance BTMSs in the pure phase, instead of a mixture of two TMSs. In this study, a binary metal center-based MOF derived selenization strategy was developed to prepare iron–cobalt selenide (Fe2CoSe4@NC) and iron–nickel selenide (Fe2NiSe4@NC) nanocomposites in the single phase and when wrapped with carbon layers. As the anode material of SIBs, Fe2CoSe4@NC exhibits higher long-term cycling performance than Fe2NiSe4@NC, maintaining a capacity of 352 mAh g−1 after 2100 cycles at 1.0 A g−1, which is ascribed to the higher percentage of the nanopores, larger lattice spacing, and faster Na+ diffusion rate in the electrode materials of the former rather than the latter. [ABSTRACT FROM AUTHOR]

Summary: To fabricate low‐saturation and low‐digestion oleogels for diet adjustment, diacylglycerol‐diosgenin (DAG‐DSG) oleogels were prepared, and in vitro digestibility was investigated. Overall, the lipolysis of DAG‐DSG oleogels was significantly lower than DAG and decreased with the increase of DSG concentrations. The lipolysis in oleogels‐3% (65%) and oleogel‐5% (45%) was about 15% and 41% lower than DAG (77%), respectively. The oleogel‐5% possessed more and smaller DSG crystals and exhibited a robust structure, inducing that oleogels were hardly destroyed to produce bigger micelles (5.42 μm) during digestion. Furthermore, intermolecular interactions in oleogels were inferred to be the van der Waal's force with Fourier transform infrared reflection and X‐ray diffraction. Thus, as‐fabricated DAG‐DSG oleogels were promisingly used as a functional food to reduce digestive lipolysis and improve dietary health. [ABSTRACT FROM AUTHOR]

The liver exhibits complex geometrical morphologies of hepatic cells arranged in a hexagonal lobule with an extracellular matrix (ECM) organized in a specific pattern on a multi-scale level. Previous studies have utilized 3D bioprinting and microfluidic perfusion systems with various biomaterials to develop lobule-like constructs. However, they all lack anatomical relevance with weak control over the size and shape of the fabricated structures. Moreover, most biomaterials lack liver-specific ECM components partially or entirely, which might limit their biomimetic mechanical properties and biological functions. Here, we report 3D bioprinting of a sacrificial PVA framework to impart its trilobular hepatic structure to the decellularized liver extracellular matrix (dLM) hydrogel with polyethylene glycol-based crosslinker and tyrosinase to fabricate a robust multi-scale 3D liver construct. The 3D trilobular construct exhibits higher crosslinking, viscosity (182.7 ± 1.6 Pa·s), and storage modulus (2554 ± 82.1 Pa) than non-crosslinked dLM. The co-culture of HepG2 liver cells and NIH 3T3 fibroblast cells exhibited the influence of fibroblasts on liver-specific activity over time (7 days) to show higher viability (90–91.5%), albumin secretion, and increasing activity of four liver-specific genes as compared to the HepG2 monoculture. This technique offers high lumen patency for the perfusion of media to fabricate a densely populated scaled-up liver model, which can also be extended to other tissue types with different biomaterials and multiple cells to support the creation of a large functional complex tissue. [ABSTRACT FROM AUTHOR]

In this study, the physical states of cellulose in 1-allyl-3-methylimidazolium chloride (AmimCl) were analyzed via rheological observations under three different conditions: namely, steady state, small amplitude oscillatory shear, and large amplitude oscillatory shear conditions. The physical state of the solution changed from an isotropic phase to a gel structure via a liquid crystalline (LC) phase as the concentration increased. The rheological analysis showed that the 16 wt% solution was physically gelled in the anisotropic phase. This instantaneous gelation at the LC phase markedly enhanced the mechanical performance of the film obtained from the solution. This study provides a fundamental strategy for significant improvement in the mechanical properties of cellulose fibers or films. [ABSTRACT FROM AUTHOR]

Integrating nanostructured MoS 2 with low-volume-change and high-rate-performance TiO 2 backbone to construct high structure stability MoS 2 -TiO 2 based composites has been turned out to be an effective strategy. However, the long-life cycling performance at high current density of all reported MoS 2 -TiO 2 based composites anodes is still suffered from their relatively low electron and ion transport kinetics. In this paper, we first demonstrate the successful synergistic regulations of both electron and ion transport kinetics benefits by controllable graphene incorporation and defect engineering in MoS 2 -TiO 2 based anodes, leading to the dramatically enhanced LIBs performance. In this optimized structure with robust structure stability, few-layer MoS 2 nanosheets are tightly anchored onto the surface of graphene/ultra-thin TiO 2 nanosheets (G/UT-TiO 2 ) backbone with chemical bonds. The graphene incorporation effectively improves the overall conductivity, while the defected structure of MoS 2 shell can significantly facilitate Li-ions transport kinetics. As a result, the as-prepared optimized anode exhibits excellent capability (648 mAh g −1 ) at high current density (1 A g −1 ) after long-life (400) cycles, accompanied by outstanding rate performance. This work can open up an avenue for the rational design of various anode materials for high performance LIBs by synergistically structural, electronic and ionic modulations. [ABSTRACT FROM AUTHOR]

• FCM has an adhesion strength of 1.2 MPa under a loading force of 5 mN, which is 3.7 times of the micropillars with a flat punch top. • FCM is quite robust that the structure and the adhesion performance are very well maintained even after1000 cycles of adhesion tests. • The structure of FCM is quite simple that it could be easily fabricated and replicated. Robust and strong adhesion is highly required for reversible adhesions. Inspired by gecko setae and octopus sucker, micropillar array with frustum of conical micropits (FCM) was fabricated by direct laser writing lithography. With an optimized micropit in FCM, the adhesion strength of 1.2 MPa is achieved under a loading force of 5 mN, which is 3.7 and 2.1 times the micropillars with flat punch top and circular conical micropit, respectively. Under a loading force larger than 3 mN, compliant contacts are formed between FCM micropillars and the counterpart surface, which results in a uniformly distributed stress at the separating interface, an instantaneous detachment of multiple FCM micropillars, and therefore a strong adhesion. Moreover, the adhesion of FCM is quite robust that 1000 cycles of attaching and detaching have no influence on the adhesion performance. The work here not only provides a bioinspired structure for strong and robust adhesion but also consolidates the concept of combining features from different biological systems to create new functional materials. [ABSTRACT FROM AUTHOR]

Architects and engineers are currently held to be two very different professions conducting different roles. However, there was a time in the distant past when architecture and civil engineering were just one discipline responsible for all types of buildings. This was the case of Ancient Egypt where the profession known as "architects" were educated in the Houses of Life as architects and engineers. Nowadays, in spite of their different education and training, these professions have many areas in common and throughout history the collaboration between the two has produced a vast wealth of iconic innovations imbued with the colour of this professional plurality. [ABSTRACT FROM AUTHOR]

Self-organization of robust and efficient networks is important for the future designs of communication or transportation systems, because both characteristics are not coexisting in many real networks. As one of the candidates for the coexisting, the optimal robustness of onion-like structure with positive degree–degree correlations has recently been found, and it can be generated by incrementally growing methods based on a pair of random and intermediation attachments with the minimum degree selection. In this paper, we introduce a continuous interpolation by a parameter β ≥ 0 between random and the minimum degree attachments to investigate the reason why the minimum degree selection is important. However, we find that the special case of the minimum degree attachment can generate highly robust networks but with low efficiency as a chain structure. Furthermore, we consider two intermediation models modified with the inverse preferential attachment for investigating the effect of distance on the emergence of robust onion-like structure. The inverse preferential attachments in a class of mixed attachment and two intermediation models are effective for the emergence of robust onion-like structure. However, a small amount of random attachment is necessary for the network efficiency, when β is large enough. Such attachment models indicate a prospective direction to the future growth of our network infrastructures. • Proposing the inverse preferential attachments (IPA) by a parametric interpolation. • IPA are effective for emergence of strongly robust onion-like network. • In the special case, the minimum degree attachment generates a chain structure. • In the mixed attachments, Small amount of randomness is necessary for short path. • In the modified models, the effect of distance is not dominant for such networks. [ABSTRACT FROM AUTHOR]

Transmission properties of light through disorder polymeric photonic crystals have been studied. The photonic crystals made of polymeric multilayers with Gaussian distribution of layer thickness are found to exhibit robust photonic bandgap (PBG). The transmission characteristics of different random structures starting from periodic to gradually perturbed structures have been systematically investigated. The numerical examples illustrate that the photonic structure can sustain its PBG for a large range of disorder up to σ = 100 nm, which is nearly equal to 15 % of the layer thickness calculated from the quarter wavelength condition for a normal incidence of light. It also quantitatively demonstrates the average transmission of the PBG region is becomes flatter due to the random nature of the structure. The proposal provides that the polymeric photonic crystal may be employed for potential applications for robust integrated photonic devices and optical communication systems. [Display omitted] • Study of Gaussian distributed random polymeric multilayers for robust photonic bandgap. • The random structures are investigated as an initial periodic structure is gradually perturbed. • The structure can sustain its PBG for a large range of disorder. • It also quantitatively demonstrates PBG becomes flatter due to the random nature of the structure. • This structure may be employed for potential applications for robust photonic and optical device or systems. [ABSTRACT FROM AUTHOR]

When incomplete repeated failure times are collected from a large number of independent individuals, interest is focused primarily on the consistent and efficient estimation of the effects of the associated covariates on the failure times. Since repeated failure times are likely to be correlated, it is important to exploit the correlation structure of the failure data in order to obtain such consistent and efficient estimates. However, it may be difficult to specify an appropriate correlation structure for a real life data set. We propose a robust correlation structure that can be used irrespective of the true correlation structure. This structure is used in constructing an estimating equation for the hazard ratio parameter, under the assumption that the number of repeated failure times for an individual is random. The consistency and efficiency of the estimates is examined through a simulation study, where we consider failure times that marginally follow an exponential distribution and a Poisson distribution is assumed for the random number of repeated failure times. We conclude by using the proposed method to analyze a bladder cancer dataset. [ABSTRACT FROM AUTHOR]

Ceramic aerogels, which present a unique combination of low thermal conductivity and excellent high-temperature stability, are attractive for thermal insulation under extreme conditions. However, most ceramic aerogels are constructed by oxide ceramic nanoparticles and thus are usually plagued by their brittleness and structural collapse at elevated temperatures (less than 1000 °C). Despite great progress achieved in this regard recently, it still remains a big challenge to design and fabricate intriguing ceramic aerogels with enhanced mechanical strength and remarkable thermal stability at ultrahigh temperature up to 1400 °C. To this end, we herein report a facile and scalable strategy to manufacture ceramic nanorod aerogels (CNRAs) with hierarchically macroporous and mesoporous structures by the controllable assembly of Al 2 O 3 nanorods and SiO 2 nanoparticles. Subsequently, the high-temperature annealing treatment of CNRAs significantly maximizes mechanical strength and promotes thermal tolerance. The obtained CNRAs demonstrate the integrated properties of super-strong heat resistance (up to 1400 °C), low thermal conductivity (0.026 W/m·K at 25 °C and 0.089 W/m·K at 1200 °C), high mechanical robustness (compressive strength 1.5 MPa), and low density (0.146 g/cm 3 ). We envision that this novel nanorod-assembled ceramic aerogels offer considerable advantages than most of the state-of-the-art ceramic aerogels for thermal superinsulation upon exposure to extremely harsh environments.

There has been a renewed interest in using lithium (Li) metal as an anode material for rechargeable batteries owing to its high theoretical capacity of 3860 mA h g -1 . Despite extensive research, modifications to effectively inhibit Li dendrite growth still result in decreased Li loading and Li utilization. As a result, real capacities are often lower than values expected, if the total mass of the electrode is taken into consideration. Herein, a lightweight yet mechanically robust carbon nanotube (CNT) paper is demonstrated as a freestanding framework to accommodate Li metal with a Li mass fraction of 80.7 wt%. The highly conductive network made of sp2-hybridized carbon effectively inhibits formation of Li dendrites and affords a favorable coulombic efficiency of >97.5%. Moreover, the Li/CNT electrode retains practical areal and gravimetric capacities of 10 mA h cm -2 and 2830 mA h g -1 (vs the mass of electrode), respectively, with 90.9% Li utilization for 1000 cycles at a current density of 10 mA cm -2 . It is demonstrated that the robust and expandable nature is a distinguishing feature of the CNT paper as compared to other 3D scaffolds, and is a key factor that leads to the improved electrochemical performance of the Li/CNT anodes., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)