Phase engineering of nanomaterials provides a promising way to explore the phase-dependent physicochemical properties and various applications of nanomaterials. A general bottom-up synthesis method under mild conditions has always been challenging globally for the preparation of the semimetallic phasetransition-metal dichalcogenide (1T′-TMD) monolayers, which are pursued owing to their unique electrochemical property, unavailable in their semiconducting 2H phases. Here, we report the general scalable colloidal synthesis of nanosized 1T′-TMD monolayers, including 1T′-MoS 2 , 1T′-MoSe 2 , 1T′-WS 2 , and 1T′-WSe 2 , which are revealed to be of high phase purity. Moreover, the surfactantreliant stacking-hinderable growth mechanism of 1T′-TMD nano-monolayers was unveiled through systematic experiments and theoretical calculations. As a proof-of-concept application, the 1T′-TMD nano-monolayers are used for electrocatalytic hydrogen production in an acidic medium. The 1T′-MoS 2 nano-monolayers possess abundant in-plane electrocatalytic active sites and high conductivity, coupled with the contribution of the lattice strain, thus exhibiting excellent performance. Importantly, the catalyst shows impressive endurability in electroactivity. Our developed general scalable strategy could pave the way to extend the synthesis of other broad metastable semimetallic-phase TMDs, which offer great potential to explore novel crystal phase-dependent properties with wide application development for catalysis and beyond.

No abstract

No abstract

No abstract

No abstract

The nylon 66-based nanocomposites containing two different surface-modified and unmodified SiO 2 nanoparticles were prepared by melt compounding. The interface structure formed in different composite system and their influences on material mechanical properties were investigated. The results indicated that the interfacial interactions differed between composite systems. The strong interfacial adhesion helped to increase tensile strength and elastic modulus of composites; whereas, the presence of modification layer in silica surface could enhance the toughness of composites, but the improvement of final material toughness was also correlated with the density of the adhered nylon 66 chains around silica nanoparticles. In addition, the results also indicated that the addition of surface-modified silica nanoparticles has a distinct influence on the nonisothermal crystallization behavior of the nylon 66 matrix when compared with the unmodified silica nanoparticle.

Chronic inflammatory diseases often lead to muscle wasting and contractile deficit. While exercise can have anti-inflammatory effects, the underlying mechanisms remain unclear. Here, we used an in vitro tissue-engineered model of human skeletal muscle (“myobundle”) to study effects of exercise-mimetic electrical stimulation (E-stim) on interferon-γ (IFN-γ)–induced muscle weakness. Chronic IFN-γ treatment of myobundles derived from multiple donors induced myofiber atrophy and contractile loss. E-stim altered the myobundle secretome, induced myofiber hypertrophy, and attenuated the IFN-γ–induced myobundle wasting and weakness, in part by down-regulating JAK (Janus kinase)/STAT1 (signal transducer and activator of transcription 1) signaling pathway amplified by IFN-γ. JAK/STAT inhibitors fully prevented IFN-γ–induced myopathy, confirming the critical roles of STAT1 activation in proinflammatory action of IFN-γ. Our results reveal a previously unknown mechanism of the cell-autonomous anti-inflammatory effects of muscle exercise and establish the utility of human myobundle platform for studies of inflammatory muscle disease and therapy.

No abstract