Targeting mitochondrial quality control with melatonin has been found promising for attenuating diabetic cardiomyopathy (DCM), although the underlying mechanisms remain largely undefined. Activation ...of SIRT6 and melatonin membrane receptors exerts cardioprotective effects while little is known about their roles during DCM. Using high‐fat diet‐streptozotocin‐induced diabetic rat model, we found that prolonged diabetes significantly decreased nocturnal circulatory melatonin and heart melatonin levels, reduced the expressions of cardiac melatonin membrane receptors, and decreased myocardial SIRT6 and AMPK‐PGC‐1α‐AKT signaling. 16 weeks of melatonin treatment inhibited the progression of DCM and the following myocardial ischemia‐reperfusion (MI/R) injury by reducing mitochondrial fission, enhancing mitochondrial biogenesis and mitophagy via re‐activating SIRT6 and AMPK‐PGC‐1α‐AKT signaling. After the induction of diabetes, adeno‐associated virus carrying SIRT6‐specific small hairpin RNA or luzindole was delivered to the animals. We showed that SIRT6 knockdown or antagonizing melatonin receptors abolished the protective effects of melatonin against mitochondrial dysfunction as evidenced by aggravated mitochondrial fission and reduced mitochondrial biogenesis and mitophagy. Additionally, SIRT6 shRNA or luzindole inhibited melatonin‐induced AMPK‐PGC‐1α‐AKT activation as well as its cardioprotective actions. Collectively, we demonstrated that long‐term melatonin treatment attenuated the progression of DCM and reduced myocardial vulnerability to MI/R injury through preserving mitochondrial quality control. Melatonin membrane receptor‐mediated SIRT6‐AMPK‐PGC‐1α‐AKT axis played a key role in this process. Targeting SIRT6 with melatonin treatment may be a promising strategy for attenuating DCM and reducing myocardial vulnerability to ischemia‐reperfusion injury in diabetic patients.
This review summarizes syntheses, structures of the amide-functionalized metal–organic frameworks (AFMOFs) with improved gas storage and separation properties mainly based upon our recent work. ...Depending where the amide groups are implanted into organic backbones, two types of AFMOFs, dynamic and robust AFMOFs were presented. After describing their syntheses and structures, in particular, several intriguingly topological platforms, i.e., pcu-, agw-, nbo-, rht-, pbz- and txt-MOFs, several outstanding AFMOFs are chosen to elucidate their applications for energy gas storage and carbon capture as well as acetylene safe handling.
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•Amide-functionalized metal–organic frameworks (AFMOFs) and their potential applications in gas storage and carbon capture based mainly upon our recent research were summarized.•AFMOFs unveil a myriad of graceful structures/topologies in combination with enhanced gas storage and separation properties.•We first pay less attention on the synthesis and structures of dynamic AFMOFs, in which the amide groups are built between carboxymethyl and phenyl rings.•Then, we discuss the designs, syntheses and constructions of robust AFMOFs by means of several intriguingly topological platforms, i.e., pcu-, agw-, nbo-, rht-, pbz- and txt-MOFs, where the amide groups are built between phenyl and phenyl rings.•Later, several outstanding AFMOFs are chosen to elucidate their applications for energy gas storage and carbon capture as well as acetylene safe handling.
Metal–organic frameworks (MOFs), emerging as a new type of solid state porous material, have received intensive attention in academia and industry over the last two decades. MOF materials demonstrate not only intriguing structures/topologies, but also a variety of functionalities/applications, i.e., mediating the currentdemanding energy crisis and environmental pollution. We are interested in the design and self-assembly of functional MOF materials to improve carbon dioxide, hydrogen, methane and acetylene storage capabilities, as well as the separation efficiencies toward flue gas and nature gas. Therefore, significant efforts have been devoted to construct a subclass of amide-functionalized metal–organic frameworks (AFMOFs) in the last decade in our research group to target the above-mentioned applications. Due to the intrinsic nature, i.e., flexibility and polarizability of amide groups, the resultant AFMOFs unveil a myriad of graceful structures/topologies in combination with enhanced gas storage and separation properties. Depending on where the amide groups are implanted into the organic backbones, two types of AFMOFs were essentially afforded in our research group. In this review, we first pay some attention to the synthesis and structures of dynamic AFMOFs, in which the amide groups are built between carboxymethyl and phenyl rings, then we discuss the designs, syntheses and constructions of robust AFMOFs by means of several intriguingly topological platforms, i.e., pcu-, agw-, nbo-, rht-, pbz- and txt-MOFs, where the amide groups are built between two phenyl rings. Later, several outstanding AFMOFs are chosen to elucidate their applications for energy gas storage and carbon capture, as well as acetylene safe handling.
Formic acid (HCOOH) is one of the most promising chemical fuels that can be produced through CO2 electroreduction. However, most of the catalysts for CO2 electroreduction to HCOOH in aqueous solution ...often suffer from low current density and limited production rate. Herein, we provide a bismuth/cerium oxide (Bi/CeOx) catalyst, which exhibits not only high current density (149 mA cm−2), but also unprecedented production rate (2600 μmol h−1 cm−2) with high Faradaic efficiency (FE, 92 %) for HCOOH generation in aqueous media. Furthermore, Bi/CeOx also shows favorable stability over 34 h. We hope this work could offer an attractive and promising strategy to develop efficient catalysts for CO2 electroreduction with superior activity and desirable stability.
The limited current density, production rate as well as selectivity hinder the improvement of HCOOH production from CO2 electroreduction. Here, bismuth/cerium oxide (Bi/CeOx) displays outstanding performances for CO2 electroreduction to HCOOH, which not only shows excellent selectivity, but also achieves a high current density (149 mA cm−2) and especially the maximum HCOOH production rate (2600 μmol h−1 cm−2) ever reported.
1D organic micro/nanostructures (OMNSs) based on π‐conjugated molecules are considered to be suitable candidates as photonic units due to their unique photophysical advantages over traditional ones ...in low‐temperature solution‐processed approach, tunable emission color, the built‐in cavity for optical confinement, and so forth. These inherent characteristics of OMNSs make them have broad application prospects in photonics devices, such as nanolasers, optical waveguides, and optical logical gates. In this review, the recent processes of OMNSs in terms of light generation, light confinement, and propagation are introduced, separately. Some representative works of OMNSs are discussed in the direction of optical modulation and processing. However, huge challenges still remain before the OMNSs are actually used as components of optical circuits in the photonics chips. The summary and the expectations are presented for the future development of 1D organic micro/nanostructures photonics.
1D organic micro/nanostructures have great potential in nanoscale integrated optical circuits as photonic components due to their intrinsic capabilities to generate and confine optical signals efficiently. Herein, the recent advances of 1D micro/nanostructures in photonic applications are reviewed. Then, the prospects and suggestions for future development are presented.
Organic heterostructures (OHSs) integrating the intrinsic heterostructure characters as well as the organic semiconductor properties have attracted intensive attention in material chemistry. However, ...the precise bottom-up synthesis of OHSs is still challenging owing to the general occurrence of homogeneous-nucleation and the difficult manipulation of noncovalent interactions. Herein, we present the rational synthesis of the longitudinally/horizontally-epitaxial growth of one-dimensional OHSs including triblock and core/shell nanowires with quantitatively-manipulated microstructure via a hierarchical self-assembly method by regulating the noncovalent interactions: hydrogen bond (-15.66 kcal mol
) > halogen bond (-4.90 kcal mol
) > π-π interaction (-0.09 kcal mol
). In the facet-selective epitaxial growth strategy, the lattice-matching and the surface-interface energy balance respectively facilitate the realization of triblock and core/shell heterostructures. This hierarchical self-assembly approach opens up avenues to the fine synthesis of OHSs. We foresee application possibilities in integrated optoelectronics, such as the nanoscale multiple input/out optical logic gate with high-fidelity signal.
Organic emitters with persistent phosphorescence have shown potential application in optoelectronic devices. However, rational design and phosphorescence tuning are still challenging. Here, a series ...of metal-free luminophores without heavy atoms and carbonyl groups from commercial/lab-synthesized carbazole and benzene were synthesized to realize tunable molecular emission from fluorescence to phosphorescence by simply substituent variation. All the molecules emit blue fluorescence in both solution and solid state. Upon removal of excitation source, the fluorinated luminophores show obvious phosphorescence. The lab-synthesized carbazole based molecules exhibit a huge lifetime difference to the commercially purchased ones due to the existence of isomer in the latter samples. The small energy gap between singlet and triplet state and low reorganization energy help enhance intersystem crossing to contribute to a more competitive radiative process from triplet to ground state. Blue and white organic light-emitting devices are fabricated by using fluorinated luminophore as emitting layer.
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•The UiO-66-NH2 membranes were grown on the α-Al2O3 substrate.•The membranes exhibited good photocatalytic Cr(VI) activities under sunlight.•Foreign ions exposed no adverse effects to ...their photocatalytic activities.•The UiO-66-NH2(Zr/Hf) membranes possessed good recyclability and stability.
The removal of toxic hexavalent chromium (Cr(VI)) ions from surface and ground water is highly demanded. While photocatalytic reduction of Cr(VI) to Cr(III) by traditional powder photocatalysts is a promising method, the difficult in the separation of the photocatalysts from the water hinders their wide practical applications. Herein we present the use of metal-organic framework (MOF) UiO-66-NH2(Zr/Hf) membrane as photocatalysts to reduce Cr(VI) ions with high efficiency and easy separation from the treated waste water. The UiO-66-NH2(Zr/Hf) MOF membrane photocatalysts were fabricated via a reactive seeding method on a α-Al2O3 substrate. It was found that the UiO-66-NH2(Zr/Hf) membranes exhibited excellent photocatalytic Cr(VI) reduction performance under both simulated and real sunlight irradiation. The UiO-66-NH2(Zr) membrane can maintain more than 94% Cr(VI) reduction efficiency after 20 cycles because of its exceptional chemical and water stability. The influences of foreign ions on Cr(VI) reduction were investigated to mimic real lake water, which revealed that no obvious adverse effects can be found with the presence of common foreign ions in surface water. The MOF membrane photocatalysts provide a new approach to carry out efficiently photocatalytic removal of pollutants in wastewater.
Deep learning methods have shown considerable potential for hyperspectral image (HSI) classification, which can achieve high accuracy compared with traditional methods. However, they often need a ...large number of training samples and have a lot of parameters and high computational overhead. To solve these problems, this article proposes new network architecture, LiteDepthwiseNet, for HSI classification. Based on 3-D depthwise convolution, LiteDepthwiseNet can decompose standard convolution into depthwise convolution and pointwise convolution, which can achieve high classification performance with minimal parameters. Moreover, we remove the ReLU layer and batch normalization layer in the original 3-D depthwise convolution, which is likely to improve the overfitting phenomenon of the model on small-sized data sets. In addition, focal loss is used as the loss function to improve the model's attention on difficult samples and unbalanced data, and its training performance is significantly better than that of cross-entropy loss or balanced cross-entropy loss. Experiment results on five benchmark hyperspectral data sets show that LiteDepthwiseNet achieves state-of-the-art performance with a very small number of parameters and low computational cost.
Anisotropic organic molecular construction and packing are crucial for the optoelectronic properties of organic crystals. Two‐dimensional (2D) organic crystals with regular morphology and good photon ...confinement are potentially suitable for a chip‐scale planar photonics system. Herein, through the bottom‐up process, 2D halogen‐bonded DPEpe‐F4DIB cocrystals were fabricated that exhibit an asymmetric optical waveguide with the optical‐loss coefficients of RBackward=0.0346 dB μm−1 and RForward=0.0894 dB μm−1 along the 010 crystal direction, which can be attributed to the unidirectional total internal reflection caused by the anisotropic molecular packing mode. Based on this crystal direction‐oriented asymmetric photon transport, these as‐prepared 2D cocrystals have been demonstrated as a microscale optical logic gate with multiple input/out channels, which will offer potential applications as the 2D optical component for the integrated organic photonics.
Guiding light: Through a bottom‐up process, 2D halogen‐bonded DPEpe‐F4DIB cocrystals were fabricated that act as an asymmetric optical waveguide with the optical‐loss coefficients of RBackward=0.0346 dB μm−1 and RForward=0.0894 dB μm−1 along the 010 crystal direction. This is further demonstrated in a microscale optical logic gate with multiple input/out channels.
White‐light‐emissive organic micro/nanostructures hold exotic potential applications in full‐color displays, on‐chip wavelength‐division multiplexing, and backlights of portable display devices, but ...are rarely realized in organic core/shell heterostructures. Herein, through regulating the noncovalent interactions between organic semiconductor molecules, a hierarchical self‐assembly approach of horizontal epitaxial‐growth is demonstrated for the fine synthesis of organic core/mono‐shell microwires with multicolor emission (red–green, red–blue, and green–blue) and especially organic core/double‐shell microwires with radial red–green–blue (RGB) emission, whose components are dibenzog,pchrysene (DgpC)‐based charge‐transfer (CT) complexes. In fact, the desired lattice mismatching (≈2%) and the excellent structure compatibility of these CT complexes facilitate the epitaxial‐growth process for the facile synthesis of organic core/shell microwires. With the RGB‐emissive substructures, these core/double‐shell organic microwires are microscale white‐light sources (CIE 0.34, 0.36). Besides, the white‐emissive core/double‐shell microwires demonstrate the fascinating full‐spectrum light transportation from 400 to 700 nm. This work indeed opens up a novel avenue for the accurate construction of organic core/shell heterostructures, which provides an attractive platform for the organic integrated optoelectronics.
Through regulating the noncovalent interactions between organic semiconductor molecules (|ECT, DgpC‐TCNB = −18.35 kcal mol−1| > |ECT, DgpC‐TFP = −13.45 kcal mol−1| > |Eπ–π, DgpC = −6.81 kcal mol−1|), a hierarchical self‐assembly approach of horizontal epitaxial‐growth is demonstrated for the precise synthesis of organic core/double‐shell microwires with radial red–green–blue (RGB) substructures for miniaturized white‐light sources (CIE 0.34, 0.36).
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