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The unique morphology of 2D van der Waals materials enables them to withstand large deformations and significant nonuniform strain, potentially inducing a strong flexoelectric effect. Despite the size‐dependent flexoelectric effect showing potential for modulating the optoelectronic performance of 2D van der Waals materials, it is far from being fully exploited owing to various challenges. Herein, the use of nanowires with different diameters as the bending media to fabricate 2D α‐In2Se3/β‐InSe heterojunctions with large curvatures of 0.1–1 µm−1 is proposed. The significant band alignment modulation in α‐In2Se3 resulting from the bending‐induced flexoelectric effect is verified through Kelvin probe force microscopy. The strain‐induced piezoelectric effect can be negated because of the weak vdW forces at the interface. The flexoelectric polarization in β‐InSe is screened via the accumulated electrons in the unilateral depleted heterojunction. Compared to the flat heterojunction, the curved heterojunction with an average curvature of 0.9 µm−1 shows 2.48‐fold and 7.62‐fold increases in open‐circuit voltage and zero‐biased responsivity, respectively. This study demonstrates the first successful modulation of photodetection in 2D heterojunctions by exploiting the flexoelectric effect, providing a new perspective for high‐performance 2D vdW optoelectronic devices. [ABSTRACT FROM AUTHOR]

Upgrading of polyethylene terephthalate (PET) waste into valuable oxygenated molecules is a fascinating process, yet it remains challenging. Herein, we developed a two‐step strategy involving methanolysis of PET to dimethyl terephthalate (DMT), followed by hydrogenation of DMT to produce the high‐valued chemical methyl p‐methyl benzoate (MMB) using a fixed‐bed reactor and a Cu/ZrO2 catalyst. Interestingly, we discovered the phase structure of ZrO2 significantly regulates the selectivity of products. Cu supported on monoclinic ZrO2 (5 %Cu/m‐ZrO2) exhibits an exceptional selectivity of 86 % for conversion of DMT to MMB, while Cu supported on tetragonal ZrO2 (5 %Cu/t‐ZrO2) predominantly produces p‐xylene (PX) with selectivity of 75 %. The superior selectivity of MMB over Cu/m‐ZrO2 can be attributed to the weaker acid sites present on m‐ZrO2 compared to t‐ZrO2. This weak acidity of m‐ZrO2 leads to a moderate adsorption capability of MMB, and facilitating its desorption. Furthermore, DFT calculations reveal Cu/m‐ZrO2 catalyst shows a higher effective energy barrier for cleavage of second C−O bond compared to Cu/t‐ZrO2 catalyst; this distinction ensures the high selectivity of MMB. This catalyst not only presents an approach for upgrading of PET waste into fine chemicals but also offers a strategy for controlling the primary product in a multistep hydrogenation reaction. [ABSTRACT FROM AUTHOR]

Converting CO2 to olefins is an ideal route to achieve carbon neutrality. However, selective hydrogenation to light olefins, especially single‐component olefin, while reducing CH4 formation remains a great challenge. Herein, we developed ZnZrOx/SSZ‐13 tandem catalyst for the highly selective hydrogenation of CO2 to light olefins. This catalyst shows C2=−C4= and propylene selectivity up to 89.4 % and 52 %, respectively, while CH4 is suppressed down to 2 %, and there is no obvious deactivation. It is demonstrated that the isolated moderate Brønsted acid sites (BAS) of SSZ‐13 promotes the rapid conversion of intermediate species derived from ZnZrOx, thereby enhancing the kinetic coupling of the reactions and inhibit the formation of alkanes and improve the light olefins selectivity. Besides, the weaker BAS of SSZ‐13 promote the conversion of intermediates into aromatics with 4–6 methyl groups, which is conducive to the aromatics cycle. Accordingly, more propene can be obtained by elevating the Si/Al ratio of SSZ‐13. This provides an efficient strategy for CO2 hydrogenation to light olefins with high selectivity. [ABSTRACT FROM AUTHOR]

Tumor microenvironment (TME)‐triggered phototheranostic platform offers a feasible strategy to improve cancer diagnosis accuracy and minimize treatment side effects. Developing a stable and biocompatible molecular phototheranostic platform for TME‐activated second near‐infrared (NIR‐II) fluorescence imaging‐guided multimodal cascade therapy is a promising strategy for creating desirable anticancer agents. Herein, a new NIR‐II fluorescence imaging‐guided activatable molecular phototheranostic platform (IR‐FEP‐RGD‐S‐S‐S‐Fc) is presented for actively targeted tumor imaging and hydrogen sulfide (H2S) gas‐enhanced chemodynamic‐hypothermal photothermal combined therapy (CDT/HPTT). It is revealed for the first time that the coupling distance between IR‐FE and ferrocene is proportional to the photoinduced electron transfer (PET), and the aqueous environment is favorable for PET generation. The part of Cyclic‐RGDfK (cRGDfk) peptides can target the tumor and benefit the endocytosis of nanoparticles. The high‐concentration glutathione (GSH) in the TME will separate the fluorescence molecule and ferrocene by the GSH‐sensitive trisulfide bond, realizing light‐up NIR‐II fluorescence imaging and a cascade of trimodal synergistic CDT/HPTT/gas therapy (GT). In addition, the accumulation of hydroxyl radicals (•OH) and down‐regulation of glutathione peroxidase 4 (GPX4) can produce excessive harmful lipid hydroperoxides, ultimately leading to ferroptosis. [ABSTRACT FROM AUTHOR]

Studying the evolution history of the southwest summer monsoon (SSM) throughout geological time, particularly during its strongest period in the Holocene, can improve our understanding of its variation and driving mechanisms, and even help predict future climate changes, due to its significant social and economic implications. Here, we reconstructed the history of chemical weathering intensity since the Last Glacial Maximum (LGM) based on clay mineral proxies [(illite/smectite)/(illite + chlorite) and illite crystallinity] obtained from Qionghai Lake sediments and examined its response to paleoclimate and SSM. Our findings indicate that the intensity of chemical weathering generally aligned with changes in paleoclimate, exhibiting strong chemical weathering intensity during warm and humid climate conditions. In addition, the intensity of chemical weathering basically tracks the evolution of the SSM since the LGM. Our results support the view that the highest SSM intensity occurred during the early‐middle Holocene, followed by gradual weakening during the late Holocene, with Northern Hemisphere summer insolation being the primary driver of the SSM evolution. The variations of the SSM and the corresponding intensity of chemical weathering were also influenced by the cumulative effects of glacier boundary conditions, North Atlantic climate fluctuations, and Intertropical Convergence Zone migrations. Key Points: Clay minerals can effectively reflect regional chemical weathering intensityChemical weathering intensity was following the monsoon variabilityThe strongest southwest summer monsoon occurred in the early‐middle Holocene [ABSTRACT FROM AUTHOR]

Identifying electrocatalysts with functions of easy dissociation of water, rapid transformation of hydroxyl and facile hydrogen‐hydrogen bond formation are indispensable while challenge for realizing efficient alkaline hydrogen evolution reaction (HER). Herein, we presented the design of Ni3Sn2‐NiSnOx nanocomposites towards addressing this challenge. We showed that Ni3Sn2 possessed ideal hydrogen adsorption and low hydroxyl adsorption abilities and NiSnOx facilitated water dissociation and hydroxyl transfer process, respectively. Consequently, the fine‐tuned interplay of the two functional parts realized the mutual coordination among the multiple functions and led to significantly boosted HER kinetics. Current densities of 10 and 1000 mA cm−2 were obtained at overpotentials of 14 and 165 mV on the optimized catalyst. This work highlights the significance of considering intrinsic interactions between active sites and all pertinent intermediates on obtaining promising electrocatalysts. [ABSTRACT FROM AUTHOR]

In this study, polylactic acid (PLA)/polycaprolactone (PCL)/microcrystalline cellulose (MCC) composites and PLA/PCL/MCC composite compatibilized by the maleic anhydride (MA) copolymer were prepared via two‐screw extrusion technology. The mechanical results showed that the strength and break elongation of the ternary composites are decreased with the increase in the MCC contents. After the grafting copolymer was added, due to the better compatibility between the components of the composite, the strength and break elongation of the composite are significantly improved compared with that of ungrafted composite. According to the conducted differential scanning calorimetry (DSC) analysis, the crystallinity of the PLA/PCL/MCC composites is increased with the increase in the MCC content, and the crystallinity of the grafted composites is higher. In addition, the 3D printed PLA/PLAma/PCL/5MCC composite exhibits good biocompatibility and adhesion with MCF‐7 cells, thus indicating its bright application prospects as a biomaterial scaffold material in tissue engineering. [ABSTRACT FROM AUTHOR]

The ever‐increasing utilization of blue light‐emitting diode in the field of the display has brought great damage to human eyes. Here, we demonstrate a method that reduces the damage caused by high concentrations of short‐wavelength blue light. Our wide spectrum and low peak backlight technology are based on replacing the existing common blue chip with a combination of shortwave blue‐chip and long‐wave blue chip. At the same time, a large number of blue‐filtering dye particles are coated on the optical film to reduce high‐energy blue light and achieve the effect of protecting the eyes. Therefore, our project can achieve up to 25 nm FWHM and a 50% reduction in peak blue light that is close to the continuous spectrum of natural light in the blue wavelength region. Numerical and experimental results, in a good agreement, demonstrate good performance of the proposed approach in liquid crystal display, with potential applications to eye‐friendly display. [ABSTRACT FROM AUTHOR]

Worldwide marine compound contamination by petroleum products and heavy metals is a burgeoning environmental concern. Pseudoalteromonas, prevalently distributed in marine environment, has been proven to degrade petroleum and plays an essential role in the fate of oil pollution under the combined pollution. Nevertheless, the research on the reference genes is still incomplete. Therefore, this study aims to thoroughly investigate the reference genes represented by Pseudoalteromonas sp. JSTW via whole‐genome sequencing. Next‐generation sequencing technology unfolded a genome of 4,026,258 bp, database including Clusters of Orthologous Groups (COG) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were utilized to annotate the genes and metabolic pathways conferring to petroleum hydrocarbon degradation. The results show that common alkane and aromatic hydrocarbon degradation genes (alkB, ligB, yqhD, and ladA), chemotaxis gene (MCP, cheA, cheB, pcaY, and pcaR), heavy‐metal resistance, and biofilm genes (σ54, merC, pcoA, copB, etc.) were observed in whole‐genome sequence (WGS) of JSTW, which indicated that strain JSTW could potentially cope with combined pollution. The degradation efficiency of naphthalene in 60 h by JSTW was 99% without Cu2+ and 67% with 400 mg L−1 Cu2+. Comparative genome analysis revealed that genomes of Pseudoalteromonas lipolytica strain LEMB 39 and Pseudoalteromonas donghaensis strain HJ51 shared similarity with strain JSTW, suggesting they are also the potential degradater of petroleum hydrocarbons under combined pollution. Therefore, this study provides a WGS annotation and reveals the mechanism of response to combined pollution of Pseudoalteromonas sp. JSTW. [ABSTRACT FROM AUTHOR]

This paper reports a method to reduce the high energy and short wave blue light damage to human eyes, by reducing the proportion of blue light in using two chips in LED as blue light chips with different main wavelengths. At the same time, the filter blue light particle are coated on the membrane to remove high‐energy short wave blue light to achieve eye protection effect. The project can increase the half‐wave width to 25 nm and reduce the blue light peak to 50%, so that the wide spectrum of the display screen is close to the continuous spectrum of natural light. The above scheme will not affect the brightness and gamut. Meanwhile, that project can maintain the original color temperature of the display, provide the best viewing effect and safeguard the human eye health while protecting the health of the users. [ABSTRACT FROM AUTHOR]

The population decline of the common hippopotamus (Hippopotamus amphibius) has necessitated the preservation of their genetic resources for species conservation and research. Of all actions, cryopreservation of fibroblast cell cultures derived from an animal biopsy is considered a simple but efficient means. Nevertheless, preserving viable cell cultures of the common hippopotamus has not been achieved to our knowledge. To this end, we established and characterized fibroblast cell cultures from the skin sample of a newborn common hippopotamus in this study. By combining the tissue explant direct culture and enzymatic digestion methods, we isolated a great number of cells with typical fibroblastic morphology and high viability. Neither bacteria/fungi nor mycoplasma was detectable in the cell cultures throughout the study. The population doubling time was 34 h according to the growth curve. Karyotyping based on Giemsa staining showed that the cultured cells were diploid with 36 chromosomes in all, one pair of which was sex chromosomes. The amplified mitochondrial cytochrome C oxidase subunit I gene sequence of the cultured cells was 99.26% identical with that of the registered H. amphibius complete mitochondrial DNA, confirming the species of origin of the cells. Flow cytometry and immunofluorescence staining results revealed that the detected cells were positive for fibroblast markers, S100A4, and vimentin. In conclusion, we generated the fibroblast cell cultures from a common hippopotamus and identified their characteristics using multiple techniques. We believe the cryopreserved cells could be useful genetic materials for future research. [ABSTRACT FROM AUTHOR]

Carboxylation of arenes utilizing CO2 into value‐added chemicals has received much attention but remains a challenge. Herein, we report a Ti−Zr oxide catalyst which shows high activity in the carboxylation of toluene with CO2‐derived dimethyl carbonate (DMC) into methyl methylbenzoates, while the individual TiO2 and ZrO2 component show poor catalytic performance. It was found that the excellent performance is related to the amorphous state of the Ti−Zr mixed‐metal oxide which possesses high acidity and moderate basicity together with high specific surface area. [ABSTRACT FROM AUTHOR]

For the current mainstream low‐blue light standards implemented internationally and domestically, including the low‐blue‐light certification standards of the TUV Rheinland certification body from German, the T/CVIA‐02‐2017 standard for low‐blue display devices proposed by the China Electronics Video Industry Association, and the blue light hazard standards related to lamps and lamp systems in IEC/EN 62471, the compliance of various indicators and blue light hazard standards have been studied, which indicators include different parameters such as brightness and color point etc of TV products. Some results such as each standard above has certain limitations for TV products have been obtained, and some suggestions for improvement of standards have been given. [ABSTRACT FROM AUTHOR]

A ferrocene-based ionic liquid (Fe-IL) is used as a metal-containing feedstock with a nitrogen-enriched ionic liquid (N-IL) as a compatible nitrogen content modulator to prepare a novel type of non-precious-metal-nitrogen-carbon (M-N-C) catalysts, which feature ordered mesoporous structure consisting of uniform iron oxide nanoparticles embedded into N-enriched carbons. The catalyst Fe10@NOMC exhibits comparable catalytic activity but superior long-term stability to 20 wt % Pt/C for ORR with four-electron transfer pathway under alkaline conditions. Such outstanding catalytic performance is ascribed to the populated Fe (Fe3O4) and N (N2) active sites with synergetic chemical coupling as well as the ordered mesoporous structure and high surface area endowed by both the versatile precursors and the synthetic strategy, which also open new avenues for the development of M-N-C catalytic materials. [ABSTRACT FROM AUTHOR]

Nitrogen-functionalized active carbon-supported ultrasmall Pd nanoparticles were conveniently prepared by using a postloading method. The Pd catalyst was highly active and selective for the hydrogenation of nitroarenes at room temperature under ambient pressure. Reducible groups such as ketone, carboxylic acid, and ester were not hydrogenated, and the corresponding anilines were obtained quantitatively. The Pd catalyst demonstrated high stability and could be reused 10 times without the loss of catalytic performance. [ABSTRACT FROM AUTHOR]