Latest ArticlesActivation of (bi)sulfite (S(Ⅳ)) by metal oxides is strongly limited by low electrons utilization. In this study, two carbon-supported cobalt ferrites spinels (CoFe2O4 QDs-GO and CoFe2O4 MOFs-CNTs) have been successfully synthesized by one-step solvothermal method. It was found that both catalysts could efficiently activate S(Ⅳ), with rapid reductive dechlorination and then oxidative degradation of a recalcitrant antibiotic chloramphenicol (CAP). Characterizations revealed that CoFe2O4 spinels were tightly coated on the carbon bases (GO and CNTs), with effectiveness of the internal transfer of electrons. O2˙− was identified for the reductive dechlorination of CAP, with simultaneously detection of both •OH and SO4˙− responsible for further oxidative degradation. The sulfur oxygen radical conversion reactions and molecular oxygen activation would occur together upon the carbon-based spinels. Spatial-separated interfacial reductive-oxidation of CAP would occur with dechlorination of CAP by O2˙− on the carbon bases, and oxidative degradation of intermediates by SO4˙−/•OH upon the CoFe2O4 catalysts.
To achieve smart and personalized medicine, the development of hydrogel dressings with sensing properties and biotherapeutic properties that can act as a sensor to monitor of human health in real-time while speeding up wound healing face great challenge. In the present study, a biocompatible dual-network composite hydrogel (DNCGel) sensor was obtained via a simple process. The dual network hydrogel is constructed by the interpenetration of a flexible network formed of poly(vinyl alcohol) (PVA) physical cross-linked by repeated freeze-thawing and a rigid network of iron-chelated xanthan gum (XG) impregnated with Fe3+ interpenetration. The pure PVA/XG hydrogels were chelated with ferric ions by immersion to improve the gel strength (compressive modulus and tensile modulus can reach up to 0.62 MPa and 0.079 MPa, respectively), conductivity (conductivity values ranging from 9 × 10-4 S/cm to 1 × 10-3 S/cm) and bacterial inhibition properties (up to 98.56%). Subsequently, the effects of the ratio of PVA and XG and the immersion time of Fe3+ on the hydrogels were investigated, and DNGel3 was given the most priority on a comprehensive consideration. It was demonstrated that the DNCGel exhibit good biocompatibility in vitro, effectively facilitate wound healing in vivo (up to 97.8% healing rate) under electrical stimulation, and monitors human movement in real time. This work provides a novel avenue to explore multifunctional intelligent hydrogels that hold great promise in biomedical fields such as smart wound dressings and flexible wearable sensors.
Regenerating spent graphite (SG) from retired lithium-ion batteries (LIBs) can effectively avoid resource waste. However, the technology is challenged by the impurity content and energy consumption. In this study, micro-expanded graphite (MEG) was synthesized by one-step oxidation method using waste LIBs anode graphite as material and perchloric acid as intercalation and oxidant agent. Then, its performance as a LIBs anode material were investigated as well as the greenhouse gas (GHG) emissions of the whole process were calculated. Perchloric acid was successfully embedded in the SG during the reaction, which effectively removed the impurities in the graphite. Defects introduced during intercalation and delamination, such as nanopores and intercrystalline cracks. Both provide additional space for Li ions during charging and discharging, thereby promoting capacity enhancement. The prepared MEG expresses a rate capability as high as 340.32 mAh/g at a current density of 0.1 C and still retains 81.73% of the capacity after 100 cycles at a current density of 1 C. Additionally, the GHG emissions of the synthesis process of this article and other literatures are compared. The results demonstrated that perchloric acid treatment process provides a low-carbon, time- and energy-saving approach for regenerated SG as battery grade material.
We report two air-stable nickel(Ⅱ) half-sandwich complexes, Cp*Ni(1,2-Cy2PC6H4O) (1) and Cp*Ni(1,2-Ph2PC6H4NH) (2), for cooperative B-H bond activation and their applications in catalytic hydroboration of unsaturated organic compounds. Both 1 and 2 react with HBpin by adding the B-H bond across the Ni−X bond (X = O or N), giving rise to the 18-electron Ni(Ⅱ)−H active species, [H1(Bpin)] and [H2(Bpin)]. Subtle tuning of the Ni−X pair and the supporting ancillary phosphine have a significant effect on the reactivity and catalytic performance of Cp*Ni(1,2-R2PC6H4X). Unlike [H2(Bpin)], the activation of HBpin in [H1(Bpin)] is reversible, which enables the Ni−O complex to be an effective cooperative catalyst in the hydroboration of N-heteroarenes, and as well as ketones and imines.
A palladium-catalyzed cascade cyclization of allenylethylene carbonates with 1,3-indandiones was developed, providing biologically interesting tetracyclic dihydrocyclopentaindenofuranone derivatives having three contiguous quaternary carbon centers in moderate to high yields with excellent diastereoselectivities. In this reaction, the allene moiety was fully fused into the cyclopentene ring.
Heme responsible for the dioxygen fixation, transport and conversion is a metalloporphyrin complex highly dependent on its diverse geometry of ligand. In this work, a trans-ortho-di-strapped zinc porphyrin with dome-like deformation was synthesized by thermodynamically controlling the formation of trans-precursor of porphyrinogen. Its single-crystal structure demonstrated that the asymmetric treatment of porphyrin achieves three goals of creating two secondary coordination sphere (SCS) bulks, maintaining a unique dome deformation, and making atomic out-of-plane deviation. In this way, this metallic complex integrates at least three key features of the pocket structure, the differentiated axial ligations, and the ring distortion, making it an ideal heme analog.
NaClO has been widely used to restore membrane flux in practical membrane cleaning processes, which would induce the formation of toxic halogenated byproducts. In this study, we proposed a novel heat-activated peroxydisulfate (heat/PDS) process to clean the membrane fouling derived from humic acid (HA). The results show that the combination of heat and PDS can achieve almost 100% recovery of permeate flux after soaking the HA-fouled membrane in 1 mmol/L PDS solution at 50 ℃ for 2 h, which is attributed to the changes of HA structure and enhanced detachment of foulants from membranes. The properties of different treated membranes are characterized by scanning electron microscopy (SEM), atomic force microscope (AFM), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), and X-ray photoelectron spectroscopy (XPS), demonstrating that the reversible and irreversible foulants could be effectively removed by heat/PDS cleaning. The filtration process and fouling mechanism of the cleaned membrane were close to that of the virgin membrane, illustrating the good reusability of the cleaned membrane. Additionally, heat/PDS which can avoid the generation of halogenated byproducts shows comparable performance to NaClO on membrane cleaning and high performance for the removal of fouling caused by sodium alginate (SA), HA-bovine serum albumin (BSA)-SA mixture and algae, further suggesting that heat/PDS would be a potential alternative for membrane cleaning in practical application.
This report describes the oxidative cyclopalladation activation of a C≡C bond during the Pd-catalyzed hydroalkylation of alkynes and analyzes potential reaction pathways based on density functional theory calculations. The more favorable pathway in-volves an oxidative cyclopalladation to generate a palladacyclopropene intermediate, which is rarely examined in Pd-catalyzed alkyne transformations. The reaction pathway proposed herein is kinetically favorable relative to the commonly proposed alkyne insertion mode. Furthermore, the Laplacians of the electron density, interaction region indicators, Mayer bond orders, and localized orbital bonding are evaluated to determine the reaction processes and characterize the key intermediates. Theoretical calculations indicate covalent bonding between a Pd(Ⅱ) center and the two C-atoms in three-membered palladacycle species. Finally, electrostatic potential analysis reveals that the regioselectivity is governed by the charge distribution on the palladacycle moiety during the protonation step.
Neglected tropical diseases (NTDs) refer to infectious diseases caused by multiple pathogens that are prevalent in hot, humid climates in tropical areas. With the global economic growth and the improvement of public health status, eliminating neglected tropical diseases will be of great significance to the healthy development of human beings. However, the number of drugs and vaccines for NTDs treatment is extremely limited, so it is urgent to develop new drugs. Since most NTDs are caused by parasites, this paper selected parasitic diseases with high morbidity and mortality, and focused on new effective therapeutic targets and excellent lead compounds for these diseases. Schistosomiasis, human African trypanosomiasis (HAT), Chagas disease, leishmaniasis, filariasis and toxoplasmosis correspond to a series targets such as smHDAC8, thioredoxin glutathione reductase (TGR), T. cruzi glucokinase (TcGlcK), phosphofructokinase (PFK), type IB topoisomerase, cell division cycle-2-related Kinase, sterolmethyl transferase, calumenin, dihydrofolate reductase (DHFR) and Toxoplasma gondii farnesyl-diphosphate synthase (TgFPPs). In this paper, the pharmacological effects of typical lead compounds corresponding to each disease, the structural characteristics of the mother nucleus and the pharmacological activities of the substituent. In addition, the binding patterns of some involved targets (such as smHDAC8) with corresponding lead compounds (such as compound 13) and the signaling pathways associated with gluconeogenesis, glycolysis, and pentose phosphate pathways are analyzed in detail. In this paper, the interaction mechanism between the lead compounds and the target were thoroughly discussed, in order to provide the research ideas of potential anti-parasite compounds, and further improve the understanding and prevention ability of such diseases of NTDs.
The construction of an integrated nanoplatform with controlled fungicide delivery features in the specific microenvironment produced by fungal pathogens is a highly desirable strategy to improve the utilization of fungicides. Herein, we report a supramolecular fungicide delivery system based on benzimidazole-modified NH2-MIL-101(Fe) metal–organic frameworks (B-MIL-101(Fe) MOFs) as carriers loaded with osthole (OS), and β-cyclodextrin (β-CD) as nanovalves to form β-CD@B-MIL-101(Fe)-OS. The nanoplatform can release the loaded OS for fungus control through self-degradation of the MOFs skeleton in an oxalic acid microenvironment produced by Botrytis cinerea. The experimental results exhibit that the constructed supramolecular fungicide delivery system could effectively inhibit mycelial growth and protect the tomatoes from infection by B. cinerea during the ripening stage. This strategy constructs a facile and integrated supramolecular drug delivery system for B. cinerea control and opens up a new avenue for the sustainable development of modern agriculture.
No. 86 Xueyuan South Road, Haidian District, Beijing
010-62662699(Operation and Technical Support)
qkjq@cast.org.cn
Copyright © 2025 China Association for Science and Technology. All rights reserved. For all open access content, the relevant licensing terms apply.
Sponsored by the Office of the Leading Group for Cybersecurity and Informatization of CAST, and supported by Science and Technology Review Publishing House
