Latest ArticlesFar-ranging and improper uses of pharmaceuticals and personal care products (PPCPs) over the last few decades have led to severe water contamination that imposes serious effects on human beings and the ecological system. Therefore, there is an increasing demand for a highly-efficient and environmentally friendly technology for the removal of PPCPs from aqueous solutions. Adsorption technology is an appropriate technology to solve this issue. Carbon-based composites, ranging from modified activated carbon to functionalized biochar, show great potential for this purpose. This review hence elaborates on the environmental occurrences and risks of PPCPs and summarizes the recent progress in removing PPCPs from water using carbon-based adsorbents. The pore structure, relatively large specific surface area (SSA), abundant surface functional groups, highly aromatic structures and the extra excellent characteristics of the cooperative materials contribute to their outstanding adsorption performance. Furthermore, the biochar-clay material is cost effective and more efficient compared to traditional activated carbon regarding the adsorption of PPCPs. Among the emerging adsorbents, graphene and carbon nanotubes composites show superior adsorption ability. Their adsorption mechanisms, such as electrostatic interactions, hydrogen bonding, and pore filling, are discussed in details.
Elemental doping confined in atomically-thin 2D semiconductors offers a compelling strategy for constructing high performance photocatalysts. Although impressive progress has been achieved based on co-thermolysis method, the choices of dopants as well as semiconductor hosts are still quite limited to yield the elaborate photocatalyst with atomic-layer-confined doping defects, owing to the difficulty in balancing the reaction kinetics of different precursors. This study shows that the cation exchange reaction, which is dictated by the Pearson's hard and soft acids and bases (HSAB) theory and allowed to proceed at mild temperatures, can be developed into a conceptually new protocol for engineering elemental doping confined in semiconductor atomic layers. To this aim, the two atomic layers of a new type of 2D photocatalyst PdSeO3 (PdSeO3 2ALs, 1.1 nm) are created by liquid exfoliation and exploited as a proof-of-concept prototype. It is demonstrated that the Mn(II) dopants with controlled concentrations can be incorporated into PdSeO3 2ALs via topological Mn2+-for-Pd2+ cation exchange performed in water/isopropanol solution at 30 ℃. The resulting Mn-doped PdSeO3 2ALs present enhanced capacity for driving photocatalytic oxidation reactions in comparison with their undoped counterparts. The findings here suggest that the new route mediated by post synthetic cation exchange promises to give access to manifold 2D confined-doping photocatalysts, with little perturbations on the thickness, morphology, and crystal structure of the atomically-thin semiconductor hosts.
Pd modified electrodes possess problems such as easy agglomeration and low electrolytic ability, and the use of manganese dioxide (MnO2) to facilitate Pd reduction of organic pollutants is just started. However, there is still a limited understanding of how to match the Pd load and MnO2 to realize optimal dechlorination efficiency at minimum cost. Here, a Pd/MnO2/Ni foam cathode was successfully fabricated and applied for the efficient electrochemical dechlorination of 2, 4, 6-trichlorophenol (2, 4, 6-TCP). The optimal electrocatalytic hydrodechlorination (ECH) performance with 2, 4, 6-TCP dechlorination efficiency (92.58% in 180 min) was obtained when the concentration of PdCl2 precipitation was 1 mmol/L, the deposition time of MnO2 was 300 s and cathode potential was −0.8 V. Performance influenced by the exogenous factors (e.g., initial pH and coexisted ions) were further investigated. It was found that the neutral pH was the most favorable for ECH and a reduction in dechlorination efficiency (6%~47.6%) was observed in presence of 5 mmol/L of NO2−, NO3−, S2− or SO32−. Cyclic voltammetry (CV) and quenching experiments verified the existence of three hydrogen species on Pd surface, including adsorbed atomic hydrogen (H*ads), absorbed atomic hydrogen (H*abs), and molecular hydrogen (H2). And the introduction of MnO2 promoted the generation of atomic H*. Only adsorbed atomic hydrogen (H*ads) was confirmed that it truly facilitated the ECH process. Besides H*ads induced reduction, the direct reduction by cathode electrons also participated in the 2, 4, 6-TCP dechlorination process. Pd/MnO2/Ni foam cathode shows excellent dechlorination performance, fine stability and recyclable potential, which provides strategies for the effective degradation of persistent halogenated organic pollutants in groundwater.
As environmental crises such as global warming become more and more serious due to the large amount of carbon dioxide emitted by the burning of fossil fuels, much attention has been paid to carbon neutrality. Hydrogen, with zero carbon content, is a clean and renewable energy carrier having a large energy density. It is considered as one of the most desirable alternatives to fossil fuels. Electrochemical water splitting, unlike the steam reforming process accelerating fossil fuels depletion and CO2 emissions, can produce H2 powered by renewable energy such as solar or wind. As a promising way to promote carbon neutralization, hydrogen production by electrolysis of water is meaningful both in terms of scientific research and practical application. In order to drive electrochemical water splitting with low power consumption, efficient, durable and affordable electrocatalysts with low overpotentials are in urgent need. Therefore, this mini-review briefly introduces the current development status and mainstream obstacles of carbon-based materials used in electrochemical water splitting.
Two novel uranium-containing selenotungstates Na3[H19(UO2)2(μ2-O)(Se2W14O52)2]·41H2O (U2) and (NH4)10[H4(SeO)2(UO2)2(H2O)2(H2Se2W14O52)(Se2W14O52)]·66H2O (Se2U2) based on the {Se2W14O52} unit were successfully prepared and fully characterized. To our knowledge, the uranium is firstly introduced into the selenotungstates. Moreover, it is notable that U2 exhibits excellent Lewis acid-base catalytic activities in the condensation cyclization of sulfonyl hydrazides with diketones to synthesize polysubstituted pyrazoles. All the desired products were obtained in moderate to good yields (up to 99%).
Here, silica microspheres were decorated with two-dimensional metal–organic frameworks (2D MOFs) nanosheets and ionic liquids, and evaluated as the mixed-mode stationary phase for chromatographic separation. The ionic liquids were used to assist the synthesis of 2D MOFs nanosheets, and also acted as adhesives among the nanosheets and silica. In contrast with the 2D MOFs-based column without ionic liquids and commercial columns, the prepared column exhibited enhanced chromatographic separation performance for partially hydrophilic compounds such as alkaloids, sulfonamides and antibiotics, etc. In addition to excellent chromatographic repeatability and stability, it has also been verified that the composites could be easily and repeatedly prepared. The relative standard deviation of the retention time of the same type of analyte between the three batches of materials was ranging from 0.21% to 1.7%. In short, these results indicated that the synthesized composites were promising separation material for liquid chromatography, which made it possible to broaden the application of 2D MOFs in the field of chromatography.
RNA molecules contain diverse modifications that display important functions in a variety of physiological and pathological processes. So far over 150 chemical modifications have been characterized to be present in various RNA species, such as in messenger RNA (mRNA), ribosomal RNA (rRNA), and transfer RNA (tRNA). Previous studies revealed that certain RNA modifications were correlated to specific human diseases, indicating RNA modifications could serve as the potential indicator of human diseases. However, systemic investigation of the alteration of RNA modifications in different RNA species of carcinoma tissues are still lacked. Herein, we carried out the comprehensive profiling and evaluation of the alteration of RNA modifications in thyroid carcinoma by liquid chromatography-tandem mass spectrometry (LC-ESI-MS/MS) analysis. The developed method allowed us to simultaneously detect 48 different types of RNA modifications. Using this method, we detected 10, 15, 14, and 25 modifications in mRNA, 18S rRNA, 28S rRNA and small RNA (< 200 nt), respectively. Compared to the normal tissues, we revealed a total of 14 RNA modification exhibited significant increase and 2 RNA modifications showed significant decrease in thyroid carcinoma tissues. Our study provided the first comprehensive profile as well as the alteration of modifications in different RNA species in thyroid carcinoma and matched tumor-adjacent normal tissues. The altered pattern RNA modifications may serve as the indicator of thyroid carcinoma. Moreover, this study may promote the in-depth understanding of the regulatory roles of RNA modifications in thyroid carcinoma.
In this work, Z-scheme V2O5 loaded fluorinated inverse opal carbon nitride (IO F-CN/V2O5) was synthesized as a product of ternary collaborative modification with heterostructure construction, element doping and inverse opal structure. The catalyst presented the highest photocatalytic activity and rate constant for degradation of typical organic pollutants Rhodamine B (RhB) and was also used for the efficient removal of antibiotics, represented by norfloxacin (NOR), sulfadiazine (SD) and levofloxacin (LVX). Characterizations confirmed its increased specific surface area, narrowed bandgap, and enhanced visible light utilization capacity. Further mechanism study including band structure study and electron paramagnetic resonance (EPR) proved the successful construction of Z-scheme heterojunction, which improved photo-generated charge carrier migration and provide sufficient free radicals for the degradation process. The combination of different modifications contributed to the synergetic improvement of removal efficiency towards different organic pollutants.
5-Hydroxymethylcytosine (5hmC), an intermediate product of DNA demethylation, is important for the regulation of gene expression during development and even tumorigenesis. The challenges associated with determination of 5hmC level include its extremely low abundance and high structural similarity with other cytosine derivatives, which resulted in sophisticated treatment with large amount of sample input. Herein, we developed a primer-initiated strand displacement amplification (PISDA) strategy to quantify the global 5hmC in genomic DNA from mammalian tissues with high sensitivity/selectivity, low input and simple operation. This sensitive fluorescence method is based on 5hmC-specific glucosylation, primer ligation and DNA amplification. After the primer was labeled on 5hmC site, DNA polymerase and nicking enzyme will repeatedly act on each primer, causing a significant increase of fluorescence signal to magnify the minor difference of 5hmC content from other cytosine derivatives. This method enables highly sensitive analysis of 5hmC with a detection limit of 0.003% in DNA (13.6 fmol, S/N = 3) from sample input of only 150 ng, which takes less than 15 min for determination. Further determination of 5hmC in different tissues not only confirms the widespread presence of 5hmC but also indicates its significant variation in different tissues and ages. Importantly, this PISDA strategy exhibits distinct advantages of bisulfite-free treatment, mild conditions and simple operation without the involvement of either expensive equipment or large amount of DNA sample. This method can be easily performed in almost all research and medical laboratories, and would provide a promising prospect to detect global 5hmC in mammalian tissues.
Owing to frequent environmental monitoring of tetrabromobisphenol-A (TBBPA) analogs and their potential ecotoxicological effects on organisms, analysis of trace levels of TBBPA analogs with more non-polar and less water-soluble characteristics is of great significance for studying their environmental behaviors and toxic effects. Herein, a fast and sensitive technique is developed for directly detecting aqueous TBBPA analogs, including TBBPA mono(allyl ether) (TBBPA-MAE), TBBPA mono(2,3-dibromopropyl ether) (TBBPA-MDBPE), TBBPA mono(2-hydroxyethyl ether) (TBBPA-MHEE) and TBBPA mono(glycidyl ether) (TBBPA-MGE), by combining solid phase microextraction (SPME) based on porous covalent organic frameworks (Porous-COFs) with constant flow desorption ionization-mass spectrometry (CFDI-MS). As chromatographic separation is replaced by constant flow desorption, each sample can be analyzed within 7 min. The hierarchical porous structures (microporous, mesoporous and macroporous) of COFs lead to the enhanced mass transfer and the easier accessibility of active sites to TBBPA analogs, so that the extraction efficiency is 2.3–3.6 times higher than pure microporous COFs, and far superior to commercial coatings. The detection limit and quantification limit of this method are 0.1–1 and 0.4–3.2 ng/L, respectively. Ultra-trace levels of TBBPA analogs from 5.0 ng/L to 66 ng/L have been successfully detected in river and sea water samples, showing great potential for subsequent studies of their environmental behaviors and toxicological effects
No. 86 Xueyuan South Road, Haidian District, Beijing
010-62199257
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
