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Abstract: DNA-wrapped multiwalled carbon nanotubes (MWCNTs) were successfully obtained by a simple sonication treatment method. The obtained materials were characterized in detail by Raman spectroscopy and scanning electron microscopy (SEM). An SEM image showed that MWCNTs were dispersed sufficiently and covered entirely with DNA. This resulted in high aqueous solubility of the products, with a stability of more than several months. The interaction between DNA and MWCNTs was confirmed by Raman measurements and was ascribed to the strong π–π interactions between the backbones of DNA and the surface of carbon nanotubes. The cyclic voltammograms showed that the composite exhibited excellent electrochemical properties. Experimental results also revealed that the high dispersion of DNA-assisted MWCNTs presented a better property compared with pristine MWCNTs. This facile method for obtaining water-soluble MWCNTs has great potential application for both bioscience and biotechnology. [Copyright &y& Elsevier]

CoP and N, O, P triple-doped carbon composites were prepared by low-temperature tandem reaction using MOF as a self-sacrificial template, and their lithium storage properties and mechanisms were investigated. [Display omitted] • The formation of dispersed cubic structure facilitates electrolyte penetration and Li+ diffusion. • Heteroatoms doping adjusts the local electric field of the anode improving the reactivity of the material. • Transformation of the mechanism of CoP anode before and after cycling was confirmed by ex-situ techniques. • Theoretical calculations demonstrate the synergistic effect between the co-doped carbon layer and CoP. Cobalt phosphide (CoP) with high theoretical capacity as well as ceramic-like and metal-like properties is considered as a promising anode for lithium-ion batteries (LIBs). However, the large volume change and sluggish kinetic response limit its practical application. The optimization of composition, structural control and performance regulation of CoP electrodes can be achieved by the bottom-up assembly technique of metal–organic frameworks (MOFs). Due to the effective electronic regulation and lithiophilicity brought by the multiple heteroatoms doping and the synergistic effect of the unique structure derived from MOFs, the N, O, P triple-doped carbon and CoP composites (ZCP@NOP) exhibited excellent rate capability (554.61 mAh g−1 at 2 A g−1) and cycling stability (806.7 mAh g−1 after 500 cycles at 0.5 A g−1). The essence and evolution of lithium storage mechanism in CoP electrodes are also confirmed by the ex-situ techniques. The synergistic benefits of heteroatom co-doping carbon and cobalt phosphide, such as the decrease of the diffusion energy barrier of Li-ions and the optimization of electronic structures, are highlighted in theoretical calculations. In conclusion, new thoughts and ideas for the creation of future battery anode are provided by the combination of the N, O, P co-doping and the adaptable structural adjustment technique. [ABSTRACT FROM AUTHOR]

MOF-derived XMn 2 O 4 (X = Zn, Co, Cu, Ni) nanomaterials achieve superior electrochemical performance for lithium storage. [Display omitted] • Two methods are proposed for the synthesis of XMn 2 O 4 (X = Zn, Co, Cu, Ni). • MOF-derived anodes exhibit excellent electrochemical capabilities compared with the ones obtained by simple coprecipitation. • Lithium storage capacity and rate performance of XMn 2 O 4 is best when X = Zn. • DFT calculations are performed to demonstrate that ZnMn 2 O 4 as an anode material is conducive to the diffusion of Li+. Bimetallic spinel transition metal oxides play a major part in actualizing eco-friendly electrochemical energy storage systems (ESSs). However, structural precariousness and low electrochemical capacitance restrict their actual implementation in lithium-ion batteries (LIBs). To address these demerits, the sacrificial template approach has been considered as a prospective way to strengthen electrochemical stability and rate performance. Herein, metal-organic frameworks (MOFs) derived XMn 2 O 4 -BDC (H 2 BDC = 1,4-dicarboxybenzene, X = Zn, Co, Cu, Ni) are prepared by a hydrothermal approach in order to discover the effects of various metal cations on the electrochemical performance. Among them, ZnMn 2 O 4 -BDC displays best electrochemical properties (1321.5 mAh g−1 at the current density of 0.1 A g−1 after 300 cycles) and high efficiency with accelerated Li+ diffusivity. Density functional theory (DFT) calculations confirm the ZnMn 2 O 4 possesses the weakest adsorption energy on Li+ with a minimized value of −0.92 eV. In comparison with other XMn 2 O 4 through traditional fabrication method, MOF-derived XMn 2 O 4 -BDC possesses a higher number of Li+ transport channels and better electric conductivity. This tactic provides a feasible and effective method for preparing bimetallic transition metal oxides and enhances energy storage applications. [ABSTRACT FROM AUTHOR]

Diabetic retinopathy (DR) is a leading cause of vision impairment and blindness among diabetics. We aimed to explore whether long-term exposure to residential greenness was beneficial to DR. We used data from a large-scale, cross-sectional screening survey conducted in 129 cities of 27 provincial regions of China from 2018 to 2021 among patients with diabetes. We measured residential greenness exposure as the 3-year average of annual maximum Normalized Difference Vegetation Index (NDVI) at a spatial resolution of 250 m. DR was assessed by ophthalmologists based on fundus photographs. The primary outcome was DR, and secondary outcome included DR severity status (i.e., nonproliferative and proliferative), hallmarks of retinal lesions and macular oedema. A total of 484,380 adult participants with diabetes were included in the current analysis, and 15.7% of them were diagnosed with DR. NDVI was inversely and linearly associated with DR prevalence, and an increment of 0.1 NDVI was associated with a 10% (9%–10%) decrease in DR prevalence. Significant and inverse associations were further found for nonproliferative and proliferative DR, hallmarks of lesions and macular oedema. The association between greenness and DR was stronger among participants who were older, obese, lived in the south, had longer duration of diabetes or did not take antidiabetic medications. This large-scale nationwide study provides the first-hand epidemiological evidence on the associations of residential greenness with DR. Our findings highlight the importance of residential greenness in alleviating DR risk especially in an era of aging and urbanization. • The first to examine the relationship between greenness and diabetic retinopathy (DR). • Greenness exposure was almost linearly associated with decreased odds of DR. • Greenness was inversely associated with nonproliferative and proliferative DR. • Greenness was inversely associated with hallmarks of DR and macular oedema. [ABSTRACT FROM AUTHOR]

Highlights • The measurement of density, viscosity and vapor pressure for three typical fatty acid 2-ethylhexyl esters were carried out. • Correlation of the density and viscosity of fatty acid 2-ethylhexyl esters using empirical temperature dependent equations. • The experimental vapor pressures were well correlated with the Antoine and Wager equations. • The Clausius-Clapeyron equation was used to calculate the molar evaporation enthalpy. Abstract Fatty acid 2-ethylhexyl esters are used for the eco-friendly production of biolubricant. There are several reports on their synthesis, but thermodynamics and transport data of these compounds are lacking. Herein, density and viscosity of palmitic acid 2-ethylhexyl ester, stearic acid 2-ethylhexyl ester and soya oil 2-ethylhexyl esters in the temperature range of T = (298.18–368.15) K at atmospheric pressure were measured and the vapor pressure in the temperature range of T = (476.95–500.85, 477.05–498.05, 477.75–500.05) K was determined. The obtained experimental data were correlated using temperature-dependence correlation equations, and the correlation coefficients of all the equations were over 0.999. In order to examine the reliability of the data, the GCVOL group method was used to evaluate densities for these fatty acid 2-ethylhexyl esters with the maximum relative deviation of −1.34%. The experimental viscosity data of synthesized 2-ethylhexyl esters were compared with those of lauric acid 2-ethylhexyl ester, palmitic acid n-octyl ester and oleic acid 2-ethylhexyl ester from previous studies. In addition, the molar enthalpy of vaporization at the mean temperature of the experimental range was calculated for the first time using the Clausius-Clapeyron equation. [ABSTRACT FROM AUTHOR]