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Arctic sea-ice extent: No record minimum in 2023 or recent years

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 52-55页

作者： Ola M.Johannessen Tor I.Olaussen Nansen Scientific Society BergenNorway Nansen environmental and Remote Sensing center BergenNorway

Arctic sea-ice extent reaches its minimum each year in September. On 11 September 2023 the minimum was 4.969 million square kilometers(***^(2)). This was not a record low, which occurred in 2012, when the minimum was 4.175 ***^(2), 0.794 ***^(2) less than the minimum in 2023. However, the ice extent had decreased by 0.432 ***^(2) compared with 2022. Nevertheless, the summer melting in 2023 was remarkably less than expected when considering the strong heat waves in the atmosphere and ocean, with record temperatures set around the world. In general, there is a high correlation between the long-term decrease in sea-ice extent and the increasing CO_(2) in the atmosphere, where the increase of CO_(2) in recent decades explains about 80% of the decrease in sea ice in September, while the remainder is caused by natural variability.

关键词： Sea ice Arctic Minimum ice Climate

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[Determination of 12 halogenated organic pollutants in edible fish by ultra performance liquid chromatography-high resolution mass spectrometry combined with ultrasound-assisted extraction and gel permeation chromatography purification]

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Se pu = Chinese journal of chromatography 2025年第1期43卷 68-77页

作者： Yi-Zhe Zhu Rui-Fen Zheng Zi-Hao Fan Ling Liu Jing-Yao Ye Kai Wang Cai-Ming Tang Research center for eco-environmental Engineering Dongguan University of Technology Dongguan 523808 China. Guangdong Key Laboratory of environmental Resources Utilization and Protection Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China.

Halogenated organic pollutants (HOPs) have attracted considerable attention owing to their persistence, bioaccumulation, and toxicity. The development of methods to detect HOPs in fish is challenging owing to the compositional complexity of fish matrices, which contain high levels of lipids and relatively low concentrations of HOPs. In addition, the lipophilicity of most HOPs renders their extraction difficult. Moreover, the simultaneous determination of multiple HOPs to achieve the high-throughput screening of these analytes is complex. In this study, a reliable and efficient pretreatment method based on ultrasound-assisted extraction, gel permeation chromatography purification, and ultra performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS) was developed for the determination of 12 HOPs in edible fish. The procedures of sample extraction and purification and LC-HRMS detection parameters were optimized to improve the performance of the method. Fresh fish samples were thoroughly rinsed with water, and non-edible parts, including the skin, bones, and phosphorus, were removed. The fish were weighed, cut into small pieces, and vacuum freeze-dried for 48 h. Subsequently, a freeze grinder was used to grind the dried fish into a fine powder. Exactly 2 g of the fish powder was weighed, fortified with isotope-labeled internal standards of the HOPs, and allowed to stand for 5 min. Methanol-acetonitrile (1∶1, v/v) was then added, followed by vortex mixing and ultrasonication. After centrifugation, the supernatant was transferred to a fresh tube. The extraction process was repeated twice and all extracts were combined. The extract was evaporated under a gentle nitrogen flow and redissolved in a mixture of ethyl acetate-cyclohexane (1∶1, v/v). The sample mixture was cleaned using gel permeation chromatography, and the eluate was collected and concentrated under a nitrogen flow. Sample residuals were reconstituted with water-methanol (1∶1, v/v) prior to

关键词： edible fish gel permeation chromatography (GPC) halogenated organic pollutants (HOPs) ultra performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS)

InNi alloy-induced interface effect promoting the parallel electron transfer: improved photothermal catalytic CO2 hydrogenation

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Science China Chemistry 2025年

作者： Haoyu Zhang Yuhang Li Yu Nie Xinyu Dou Haodong Ji Xin Tan Jinhua Ye Tao Yu School of Chemical Engineering and Technology Tianjin University eco-environment and Resource Efficiency Research Laboratory School of Environment and Energy Peking University Shenzhen Graduate School School of environmental Science and Engineering Tianjin University Advanced Catalytic Materials Research center School of Materials Science and Engineering Tianjin University Research center for Solar Driven Carbon Neutrality Hebei University

Photothermal catalytic CO2hydrogenation is an effective means of utilizing carbon ***,it is severely limited in terms of kinetics and ***,it is necessary to meticulously design catalysts to solve this ***,a sandwich structured NiO@InNi/In2O3is designed to intrinsically regulate the direction of photogenerated carriers transfer,resulting in a CO yield of 42.97 mmol g-1h-1(1290.3μmol h-1) with a selectivity near to 100%.InNi alloy favors the collection of photogenerated carriers by the parallel way and enhancement of the adsorption and activation of *** grown on the surface of InNi alloy not only improves the adsorption of H2and provides sufficient H+for the reaction,but also makes InNi alloy more stable during the reaction *** photothermal effect caused by In2O3accelerates the transfer of photogenerated carriers and increases the surface temperature of the catalyst,thereby synergistically promoting the reaction from a kinetic *** work ameliorates the kinetic and thermodynamic limitations of the photothermal catalytic CO2hydrogenation process through rationally designing the electron transfer direction of the sandwich structured catalysts to parallel way.

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[Current advances in the analysis of free RNA modified nucleosides by high performance liquid chromatography-tandem mass spectrometry]

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Se pu = Chinese journal of chromatography 2025年第1期43卷 3-12页

作者： Lyu-Ye Zhang Wei-Bing Zhang Hai-Lin Wang State Key Laboratory of environmental Chemistry and ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China. Shanghai Key Laboratory of Functional Materials Chemistry School of Chemistry & Molecular Engineering East China University of Science and Technology Shanghai 200237 China. State Key Laboratory of environmental Chemistry and ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China 3. University of Chinese Academy of Sciences Beijing 100049 China. University of Chinese Academy of Sciences Beijing 100049 China.

Post-transcriptional ribonucleic acid (RNA) modifications play crucial roles in regulating gene expression, with both eukaryotic and prokaryotic RNA exhibiting more than 170 distinct and ubiquitous modifications. RNA turnover generates numerous free nucleosides, including unmodified nucleosides and a variety of modified ones. Unlike unmodified nucleosides, modified nucleosides are not further degraded or used in the salvage-synthesis pathway owing to a lack of specific enzymes, which leads to the cytosolic accumulation or cellular efflux of modified nucleosides. These modified nucleosides can act as signaling molecules that regulate downstream pathways once transported to the extracellular space; alternatively, they are metabolized in the bloodstream and excreted in urine. Metabolized modified nucleosides are altered by cellular stress responses and mediate abnormal physiological states. Changes in the urinary and blood levels of modified nucleosides associated with cancer can serve as biomarkers for disease. Therefore, identifying and accurately quantifying nucleosides is vital for understanding RNA degradation and associated patterns of nucleoside metabolism. Such analyses are helpful when studying the biological functions and potential clinical applications of modified nucleosides. In this regard, high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) offers significant advantages in terms of sensitivity, selectivity, and efficiency, and has been widely used to analyze DNA and RNA nucleosides/nucleotides and their analogues. Multiple MS detection patterns and quantification methods have been established to detect nucleosides in biological samples, including cultured cells, urine, blood, and tissue samples. However, the development of an accurate HPLC-MS/MS method faces several challenges. Firstly, the presence of a complex biological matrix that contains macromolecules, small molecules, and salts can interfere with analysis. Salts and co-elu

关键词： RNA modifications high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) metabolite analysis methylated nucleosides

Characterization and reactivity of biogenic manganese oxides for ciprofloxacin oxidation

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Journal of environmental Sciences 2014年第5期26卷 1154-1161页

作者： Jinjun Tu Zhendong Yang Chun Hu Jiuhui Qu State Key Laboratory of environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesResearch Center for Eco-Environmental Sciences

Biogenic manganese oxides （BioMnOx） were synthesized by the oxidation of Mn（II） with Mn- oxidizing bacteria Pseudomonas sp. G7 under different initial pH values and Mn（II） dosages, and were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and UV-Vis absorption spectroscopy. The crystal structure and Mn oxidation states of BioMnOx depended on the initial pH and Mn（lI） dosages of the medium. The superoxide radical （O2） was observed in Mn-containing （III/IV） BioMnOx suspensions by electron spin resonance measurements. BioMnOx（0.4）-7, with mixed valence of Mn（II/III/IV） and the strongest O^- signals, was prepared in the initial pH 7 and Mn（II） dosage of 0.4 mmol/L condition, and exhibited the highest activity for ciproftoxacin degradation and no Mn（II） release. During the degradation of ciprofloxacin, the oxidation of the Mn（II） formed came from biotic and abiotic reactions in BioMnOx suspensions on the basis of the Mn（II） release and O2- formation from different BioMnOx. The degradation process of ciprofloxacin was shown to involve the cleavage of the hexatomic ring having a secondary amine and carbon-carbon double bond connected to a carboxyl group, producing several compounds containing amine groups as well as small organic acids.

关键词： Mn oxidation state Mn-oxidizing bacteria superoxide radicals ciprofloxacin degradation

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Accumulation of polybrominated diphenyl ethers in breast milk of women from an e-waste recycling center in China

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Journal of environmental Sciences 2017年第2期29卷 305-313页

作者： Xinghong Li Yuan Tian Yun Zhang Yujie Ben Quanxia Lv State Key Laboratory of environmental Chemistry and ecotoxicology Research Center of Eco-Environment SciencesChinese Academy of Sciences Department of environmental Science and Engineering Beijing Technology and Business University

Polybrominated diphenyl ethers（PBDEs） can be transferred to infants through the ingestion of breast milk, resulting in potential health risk. In this study, PBDEs, hydroxylated polybrominated diphenyl ethers（OH-PBDEs） and 2,2′,4,4′,5,6′-hexachlorobiphenyl（CB-153）in human milk from women living adjacent to e-waste recycling sites of Wenling,China, were investigated. The median level of PBDEs in samples from residents living in the e-waste recycling environment 〉 20 years（R20group, 19.5 ng/g lipid weight（lw））was significantly higher than that for residents living in Wenling 〈 3 years（R3group,3.88 ng/g lw）（p 〈 0.05）, likely ascribable to specific exposure to PBDEs from e-waste recycling activities. In the R20 group, most congeners（except for BDE-209） were correlated with each other（p 〈 0.05）. Moreover, CB-153 showed significant association with most PBDE congeners, rather than BDE-209. The relationship indicated that most BDE congeners other than BDE-209 shared common sources and/or pathways with CB-153, e.g., dietary ingestion. The correlations between BDE-209 and other congeners were different in the two groups, likely suggesting their different exposure sources and/or pathways for *** estimated dietary intake of PBDEs for infants via breast milk was lower than the minimum value affecting human health, the PBDE exposure of infants should be of great concern because of their potential effect on the development of neonates over long-term exposure. OH-PBDEs were not detected in the collected samples, which is in accordance with reports in published literature, likely indicating that they were not apt to be accumulated in human milk.

关键词： PBDEs OH-PBDEs Human milk E-waste

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[Construction of a 17 β-estradiol sensor based on a magnetic graphene oxide/aptamer separating material]

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Se pu = Chinese journal of chromatography 2025年第1期43卷 87-95页

作者： Xin-Yu Jin Le-Yuan Chen Ya-Nna Liu Wen-Jing Xie Han-Yong Peng State Key Laboratory of environmental Chemistry and ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China. University of Chinese Academy of Sciences Beijing 100049 China. School of Environment Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences Hangzhou 310024 China.

17-Estradiol (E2) is a natural steroidal estrogen essential for a variety of physiological functions in organisms. However, external E2, which is renowned for its potent biological effects, is also considered to be an endocrine-disrupting compound (EDC) capable of disturbing the normal operation of the endocrine system, even at nanogram-per-liter (ng/L) concentrations. Studies have revealed that medical and livestock wastewater can be contaminated with E2, which poses potential risks to human health. Currently, the primary method for detecting E2 relies on liquid chromatography-mass spectrometry, which is limited with regard to on-site or large-scale sample testing due to instrumental constraints. Herein, we developed a magnetic graphene oxide (MGO)/aptamer separating material. The MGO was synthesized by creating a water-in-oil microemulsion at 90 ℃, an agarose hydrogel to load the FeO nanoparticles, and layered graphene oxide (GO). In contrast to conventional methods, such as chemical co-precipitation and solvothermal approaches, this method is more time-efficient and does not require high temperature or pressure. Moreover, the use of a physical encapsulation technique for enwrapping the FeO nanoparticles and layered GO eliminates the need for chemical modification. This approach reduces the use of harmful chemicals, ensures complete loading, and results in highly efficient encapsulation. The MGO was characterized using Fourier-transform infrared (FT-IR) spectroscopy and transmission electron microscopy (TEM), as well as dynamic light scattering (DLS) and Zeta potential analyses, which revealed that the FeO nanoparticles had been successfully loaded onto the GO to produce MGO particles mainly around 5 μm in size. Additionally, this study demonstrated that the aqueous MGO dispersion is highly stable. This substance was used to develop a fluorescent biosensor that uses a "turn-on" mechanism to rapidly and highly sensitively detect E2. MGO is capable of adsorbing a fl

关键词： 17-estradiol (E2) fluorescence biosensor magnetic graphene oxide (MGO) magnetic solid phase separation

De novo origination of the micropeptide controlling kernel dehydration in maize

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Science China Life Sciences 2025年

作者： Yuanliang Liu Manman Li Mingliang Xu State Key Laboratory of Plant environmental Resilience College of Agronomy and Biotechnology National Maize Improvement Center Center for Crop Functional Genomics and Molecular Breeding China Agricultural University

The mechanization of maize harvest plays a pivotal role in global food security and agricultural productivity. However, in China and many other countries, maize harvesting remains largely unmechanized, with less than ...

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LiDAR-Visual SLAM with Integrated Semantic and Texture Information for Enhanced ecological Monitoring Vehicle Localization

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Computers, Materials & Continua 2025年第1期82卷 1401-1416页

作者： Yiqing Lu Liutao Zhao Qiankun Zhao Foreign environmental Cooperation center Ministry of Ecology and Environment of PRCBeijing100035China Beijing Computing center Co. Ltd.Beijing Academy of Science and TechnologyBeijing100083China Beijing Guyu Interactive Artificial Intelligence Application Co. Ltd.Beijing100024China

ecological monitoring vehicles are equipped with a range of sensors and monitoring devices designed to gather data on ecological and environmental *** vehicles are crucial in various fields,including environmental science research,ecological and environmental monitoring projects,disaster response,and emergency management.A key method employed in these vehicles for achieving high-precision positioning is LiDAR(lightlaser detection and ranging)-Visual Simultaneous Localization and Mapping(SLAM).However,maintaining highprecision localization in complex scenarios,such as degraded environments or when dynamic objects are present,remains a significant *** address this issue,we integrate both semantic and texture information from LiDAR and cameras to enhance the robustness and efficiency of data ***,semantic information simplifies the modeling of scene elements,reducing the reliance on dense point clouds,which can be less ***,visual texture information complements LiDAR-Visual localization by providing additional contextual *** incorporating semantic and texture details frompaired images and point clouds,we significantly improve the quality of data association,thereby increasing the success rate of *** approach not only enhances the operational capabilities of ecological monitoring vehicles in complex environments but also contributes to improving the overall efficiency and effectiveness of ecological monitoring and environmental protection efforts.

关键词： LiDAR-Visual simultaneous localization and mapping integrated semantic texture information