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Photoinduced bending behavior triggered by [2 + 2] cycloaddition of a photoactive complex has been successfully achieved, accompanied by photochromic and fluorescence changes that provide convenience for long-distance observation of photomechanical motion. The key design feature is based on the introduction of flexible methylene groups and cation–π interactions. Moreover, the potential application in photomechanical devices was reflected by bending and supporting force experiments on the complex composite film, which is of increasing importance especially in soft actuators and robots. [ABSTRACT FROM AUTHOR]

Silicon has received much attention due to its high theoretical capacity as the electrode of lithium-ion batteries (LIBs). However, the poor stability caused by the volume expansion problem affects the cycle life of batteries, thus severely limiting the application of the silicon anode. In the present work, we engineered silicon nanotubes with hollow-structure to accommodate the volume expansion of silicon and improve the electrochemical stability of lithium ion batteries. Hollow silicon nanotubes were in situ synthesized on carbon cloth (HSiNTs/CC) by reducing silicon oxide and corroding zinc oxide nanorod templates and directly used as the anode of lithium-ion batteries without any binders or conductive additives. The results of electrochemical measurements indicated that HSiNTs/CC exhibits superior LIB performance with excellent cycling stability and good rate capability. At a current density of 100 mA g−1, a reversible capacity of 1420 mA h g−1 was achieved and the fabricated LIB could retain 93.7% of the initial capacity after 100 cycles. Even at a decoupled current density of 1000 mA g−1, the LIB still possesses a capacity of 1026 mA h g−1 and 98.3% capacity retention after 100 cycles. The results demonstrated that the thin hollow structures were well suited to accommodate the volume expansion of silicon and improve the stability of the HSiNTs/CC anode during the lithiation–delithiation cycles, which shines some light on the reasonable design and preparation of silicon anodes for ultra-stable lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Three novel indole-based ligand precursors [HIndPhR, R = methoxy, HIndPhOMe (2a); thiomethoxy, HIndPhSMe (2b); and N,N′-dimethylamino, HIndPhNMe2 (2c)] have been synthesized via Sonogashira and cyclization reactions with moderate to high yield. Reactions of these ligand precursors with 0.6 equivalent of MgnBu2 in THF afforded the magnesium bis-indolyl complexes 3a–3c, respectively. All the ligand precursors and related magnesium complexes have been characterized by NMR spectroscopy and elemental analyses. The molecular structures are reported for compounds 3a and 3b. Under optimized conditions, compound 3a demonstrates efficient catalytic activities towards the ring opening polymerization of l-lactide and ε-caprolactone in the presence of BnOH. [ABSTRACT FROM AUTHOR]

The osmium(VI) nitrido complex [OsVI(N)(sap)(py)Cl] is a potential anti-cancer drug with promising in vitro antiproliferative activities toward a panel of cancer cell lines, including cisplatin-resistant cells (IC50 values of 2.8–13.8 μM). This drug targets DNA and changes its conformation via covalent binding and insertion. In vitro studies indicate that the drug induces HepG2 cells G2/M phase arrest, disrupts the mitochondrial membrane potential and causes caspase-mediated apoptosis. Further in vivo studies using HepG2-bearing nude mice reveal that this drug not only shows good antitumor efficacy of inhibiting tumor growth, but also does not show the side effect of weight loss. [ABSTRACT FROM AUTHOR]

A series of color-tunable NaBa1−zSrzB9O15:Ce3+,Mn2+ phosphors were synthesized by a high temperature solid state method. Luminescence property, energy transfer, thermal stability and cation substitution were investigated in detail. Due to energy transfer, NaBaB9O15:Ce3+,Mn2+ presents violet to green luminescence and manifest a broad excitation range from 200 to 350 nm. The energy transfer mechanism of Ce3+–Mn2+ is identified as a dipole–dipole interaction. NaBa1−zSrzB9O15:Ce3+,Mn2+ displays both Ce3+ violet and Mn2+ green and orange emissions under ultraviolet excitation. It is observed that Sr2+ partial substitution for Ba2+ could adjust the ratio of Mn2+ emission intensity in different cation sites, which results from preferred sites’ occupation with modification of the crystal structure. Furthermore, increase in temperature can enhance the energy transfer from Ce3+ to Mn2+, which enhances the Mn2+ emission intensity sharply. The highly thermal-sensitive property of NaBa1−zSrzB9O15:Ce3+,Mn2+ makes it feasible for its potential application in luminescent ratiometric thermometers with wide temperature range. [ABSTRACT FROM AUTHOR]