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Significant changes in the physicochemical properties of BC-containing particles during the cold season in Beijing

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Journal of Environmental Sciences 2025年第5期151卷 667-676页

作者： Shuya Hu Linghan Zeng gang Zhao Shiyi Chen Chunsheng Zhao Weilun Zhao min Hu State Key Joint Laboratory of Environmental Simulation and Pollution Control International Joint Research Center for Atmospheric Research(IJRC)College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China Department of Atmospheric and Oceanic Sciences School of PhysicsPeking UniversityBeijing 100871China Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Nanjing University of Information Science and TechnologyNanjing 210044China

The ambient air quality has improved significantly under strict emission controls in Beijing,China over the last *** carbon(BC),as a short-lived climate forcer in ambient aerosols,profoundly impacts the air quality and *** studies have demonstrated a decline in the mass concentration of *** this study,we characterized the chemical compositions and size distributions of BC-containing particles during the cold season of 2022 in Beijing using state-of-the-art instruments capable of exclusively measuring BCcontaining *** optical properties of BC-containing particles were further calculated based on the Mie ***,we compared the properties of BC-containing particles in 2022 with the results of previous *** results showed that the diameters of BC cores became larger while the coating thickness of BC-containing particles became thinner in *** the coating materials,the mass fraction of nitrate increased obviously,and even replaced organic matter as the dominant component during the peak of the pollution *** in chemical compositions and size distributions resulted in lower mass absorption cross-sections(MAC)of BC-containing particles from 10.5±1.1 m^(2)/g in 2016 to 7.3±0.8 m^(2)/g in 2022,reduced by 30.5%.Our results demonstrate the synergistic benefits of air pollution control in improving air quality and mitigating climate ***,the MAC of BC adopted in climate models should vary with the changing air pollution *** study emphasizes that it is imperative to conduct long-term observations of BC-containing particles to better estimate BC’s climate effects.

关键词： Black carbon Chemical composition Size distribution Light absorption ability

Oxygen vacancies-rich molybdenum tungsten oxide nanowires as a highly active nitrogen fixation electrocatalyst

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Chinese Chemical Letters 2025年第1期36卷 545-548页

作者： Jincheng Zhang Mengjie Sun Jiali Ren Rui Zhang min Ma Qingzhong xue Jian Tian School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590China

Herein,vacancy engineering is utilized reasonably to explore molybdenum tungsten oxide nanowires(W_(4)MoO_(3)NWs)rich in O-vacancies as an advanced electrochemical nitrogen reduction reaction(eNRR)electrocatalyst,realizing further enhancement of NRR *** 0.1 mol/L Na_(2)SO_(4),W_(4)MoO_(3)NWs rich in O vacancies(CTAB-D-W_(4)MoO_(3))achieve a large NH3yield of 60.77μg h^(-1)mg^(-1)***-0.70 V *** and a high faradaic efficiency of 56.42%at-0.60 V,much superior to the W_(4)MoO_(3)NWs deficient in oxygen vacancies(20.26μg h^(-1)mg^(-1)*** 17.1%at-0.70 V ***).Meanwhile,W_(4)MoO_(3)NWs rich in O-vacancies also show high electrochemical *** functional theory(DFT)calculations present that O vacancies in CTAB-D-W_(4)MoO_(3)reduce the energy barrier formed by the intermediate of^(*)N-NH,facilitate the activation and further hydrogenation of^(*)N-N,promote the NRR process,and improve NRR activity.

关键词： Electrocatalytic N_(2) reduction reaction Molybdenum-tungsten oxide Nanowires Oxygen vacancies Non-noble metal

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Impacts of near-M_(s)austempering treatment on microstructure evolution and bainitic transformation kinetics of a medium Mn steel

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Journal of Iron and Steel Research International 2025年第1期32卷 249-259页

作者： Yong-gang Yang Xin-yue Liu Rui-zhi Li Yu-lai Chen Hong-xiang Wu Guo-min Sun Zhen-li Mi National Engineering Research Center for Advanced Rolling and Intelligent Manufacturing University of Science and Technology BeijingBeijing 100083China Technology Center Ningbo Iron&Steel Co.Ltd.Ningbo 315800ZhejiangChina

The microstructure evolution and bainitic transformation of an Fe-0.19C-4.03Mn-1.48Si steel subjected to near-M_(s)austempering treatment were systematically investigated by combining dilatometer,X-ray diffraction,and electron *** additional austempering treatments with isothermal temperatures above M_(s)were used as *** show that the incubation period for the bainitic transformation occurs when the medium Mn steel is treated with the austempering temperature above M_(s).However,when subjected to near-M_(s)isothermal treatment,the medium Mn steel does not show an incubation period and has the fastest bainitic transformation ***,the largest volume fraction of bainite with a value of 74.7%is obtained on the condition of near-M_(s)austempering treatment after cooling to room *** and microstructure evolution analysis indicates that the elimination of the incubation period and the fastest rate of bainitic transformation are related to the preformed *** advent of preformed martensite allows the specimen to generate more bainite in a limited *** bainitic ferrite nucleation at austenite grain boundaries and through autocatalysis at ferrite/austenite interfaces,a model is established to understand the kinetics of bainite formation and it can describe the nucleation rate of bainitic transformation well when compared to the experimental results.

关键词： Medium manganese steel Bainitic transformation Microstructure Near-M_(s)austempering Transformation modeling

Conjunctival microbiota variations in a subset of middleaged and elderly individuals from Beijing,China

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International Journal of Ophthalmology(English edition) 2025年第2期18卷 237-243页

作者： Tian-Yao Zhao Yu-Chen Wang Ying-Juan Sun Jun-Yue Wang Xiao-Dan Jiang xue-min Li Ai-Hua Deng Department of Ophthalmology Peking University Third HospitalBeijing Key Laboratory of Restoration of Damaged Ocular NerveBeijing 100191China Fangshan Hospital Beijing University of Chinese Medicine Beijing 102400China CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China State Key Laboratory of Animal Nutrition and Feeding Ministry of Agriculture and Rural Affairs Feed Industry CentreAgricultural UniversityBeijing 100193China

AIM:To isolate and identify the conjunctival microbiota of cataract patients and analyze the associated influencing ***:This study recruited 216 participants(216 eyes)from April 2022 to July *** the condition of no antibiotic use prior to cataract surgery,sterile swabs were used to collect samples from the lower conjunctival *** cultures were then conducted,followed by species identification through 16S rDNA gene *** factors associated with positive or negative bacterial isolation rates were analyzed,including age,gender,meibomian gland dysfunction(MGD),history of hypertension,history of diabetes,history of cancer,history of infectious diseases and the habit of wearing ***:Among the 216 eyes,78 eyes yielded isolates,with an isolation rate of 36.11%,detecting a total of 122 ***-positive rods accounted for 49.18%(60 strains),gram-positive cocci accounted for 45.08%(55 strains),gram-negative bacteria accounted for 4.92%(6 strains),and fungi accounted for 0.82%(1 strain).This study found that the most abundant genera in the conjunctival sac were Corynebacterium(42.62%),Staphylococcus(31.15%),Micrococcus(9.84%),Acinetobacter(4.10%),and Bacillus(3.28%).Furthermore,age(P=0.006),gender(P=0.039),diabetes(P=0.003),history of infectious diseases(P=0.02),and duration of mask replacement(P<0.001)were important factors influencing the positive bacterial culture of the conjunctival *** hypertensive patients exhibited a higher isolation rate of conjunctival bacteria,it did not reach statistical significance,and the history of cancer did not affect the isolation rate of the conjunctival microbial community in cataract patients before ***:Potential changes are observed in the conjunctival microbiota among a sample of middleaged and elderly individuals from Beijing,***,an increased isolation rate of Corynebacterium and Micrococcus is detected,suggesting a possible change in the mic

关键词： conjunctival microbiota 16S rDNA middle-aged and elderly population mask cataract surgery

RGS22 maintains the physiological function of ependymal cells to prevent hydrocephalus

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Science China(Life Sciences) 2025年第2期68卷 441-453页

作者： xue Pang Lin Gu Qiu-Ying Han Jia-Qing Xing ming Zhao Shao-Yi Huang Jun-Xi Yi Jie Pan Hao Hong Wen xue xue-Qing Zhou Zhi-Hui Su Xin-Ran Zhang Li-ming Sun Shao-Zhen Jiang Dan Luo Ling Chen Zheng-Jie Wang Yu Yu Tian Xia xue-min Zhang Ai-Ling Li Tao Zhou Hong Cai Tao Li Nanhu Laboratory National Center of Biomedical AnalysisBeijing 100039China School of Basic Medical Sciences Fudan UniversityShanghai 200032China Department of Basic Medical Sciences School of MedicineTsinghua UniversityBeijing 100084China

Ependymal cells line the wall of cerebral ventricles and ensure the unidirectional cerebrospinal fluid(CSF)flow by beating their motile cilia *** ependymal denudation or ciliary dysfunction causes ***,we report that the deficiency of regulator of Gprotein signaling 22(RGS22)results in severe congenital hydrocephalus in both mice and ***,RGS22 is specifically expressed in ependymal cells within the *** conditional knock-out mice,we further demonstrate that the deletion of Rgs22 exclusively in nervous system is sufficient to induce ***,we show that Rgs22 deficiency leads to the ependymal denudation and impaired *** phenomenon can be attributed to the excessive activation of lysophosphatidic acid receptor(LPAR)signaling under Rgs22^(-/-)condition,as the LPAR blockade effectively alleviates hydrocephalus in Rgs22^(-/-)***,our findings unveil a previously unrecognized role of RGS22 in the central nervous system,and present RGS22 as a potential diagnostic and therapeutic target for hydrocephalus.

关键词： RGS22 hydrocephalus ependymal cells

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Improved rate and cycling performances of Na_(3)V_(2)(PO_(4))_(2)F_(2)O by Ti^(3+/4+)doping with two oxidation states for sodium cathodes

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中国有色金属学报 2025年第1期35卷 243-256页

作者： Xiao-fei SUN Anastase NDAHIMANA Ling-zhi WANG Zi-kang WANG Quan-sheng LI Wei TANG min-xing YANG xue-song MEI State Key Laboratory for Manufacturing System Engineering Xi’an Jiaotong UniversityXi’an 710049China School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China Shaanxi Key Laboratory of Intelligent Robots Xi’an Jiaotong UniversityXi’an 710049China School of Chemical Engineering and Technology Xi’an Jiaotong UniversityXi’an 710049China

Ti at the oxidation states of Ti^(3+)and Ti^(4+),was used to enhance the performance of Na_(3)V_(2)(PO_(4))_(2)F_(2)O by partially substituting *** doping Ti,the crystallographic volume is decreased due to the less radii of Ti^(3+/4+),and the valence of Ti is demonstrated identical to *** sodium insertion in Ti-doped Na_(3)V_(2)(PO_(4))_(2)F_(2)O,the two discharge plateaus split into three because of the rearrangement of local redox ***,the optimized Na_(3)V_(0.96)Ti_(0.04)(PO_(4))_(2)F_(2)O shows a specific capacity of 123 and 63 mA·h/g at 0.1C and 20C,*** 350 cycles at 0.5C,the capacity is gradually reduced corresponding to a retention of 71.05%.The significantly improved performance is attributed to the rapid electrochemical kinetics,and showcases the strategy of replacing V^(3+/4+)with Ti^(3+/4+)for high-performance vanadium-based oxyfluorophosphates.

关键词： sodium vanadium oxyfluorophosphate titanium doping cathode sodium battery energy storage

Partial multi-label learning via label-specific feature corrections

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Science China(Information Sciences) 2025年第03期68卷 95-109页

作者： Jun-Yi HANG min-Ling ZHANG School of Computer Science and Engineering Southeast University Key Laboratory of Computer Network and Information Integration(Southeast University) Ministry of Education

Partial multi-label learning（PML） allows learning from rich-semantic objects with inaccurate annotations, where a set of candidate labels are assigned to each training example but only some of them are valid. Existing approaches rely on disambiguation to tackle the PML problem, which aims to correct noisy candidate labels by recovering the ground-truth labeling information ahead of prediction model induction. However, this dominant strategy might be suboptimal as it usually needs extra assumptions that cannot be fully satisfied in real-world scenarios. Instead of label correction, we investigate another strategy to tackle the PML problem, where the potential ambiguity in PML data is eliminated by correcting instance features in a label-specific manner. Accordingly, a simple yet effective approach named PASE, i.e., partial multi-label learning via label-specific feature corrections, is proposed. Under a meta-learning framework, PASElearns to exert label-specific feature corrections so that potential ambiguity specific to each class label can be eliminated and the desired prediction model can be induced on these corrected instance features with the provided candidate labels. Comprehensive experiments on a wide range of synthetic and real-world data sets validate the effectiveness of the proposed approach.

关键词： machine learning multi-label learning partial multi-label learning label-specific features feature correction

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Prediction of Antibacterial Activity for Chemical Agents with Support Vector Machine

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Prediction of Antibacterial Activity for Chemical Agents wit...

EDA-complexes-enabled photochemical synthesis of α-amino acids with imines and tetrabutylammonium oxalate

第九届全国计算（机）化学学术会议

作者： xue-gang Yang~1 min Wang~1 Ying xue~(1,2*) Guo-sen Yan~1 1 College of Chemistry,Sichuan University,Chcngdu 610064,P.R.China 2 State Key Laboratory of Biothcrapy,Sichuan University,Chcngdu 610041,P.R.China

＜正＞Bacterial infections are commonly and frequently encountered *** diseases are caused by bacterial *** the antibacterial drugs are extensively used in clinic. Recently,drug-resistant bacteria and variant strains have emerged with the increasing use of antibacterial *** it is desirable to discover and develop highly-efficient and new antibacterial *** discriminant analysis（LDA）and binary logistic regression（BLR）have been successfully used for the prediction of antibacterial activity with a prediction accuracy of 90%.In the present work,a Support Vector Machine（SVM）method was used to process classification modeling and prediction for the antibacterial activi.y Of *** Support Vector Machine（SVM）method is a new supervised machine learning method which is built on Statistical Learning Theroy（SLT）.It has strong learning capability and extensive capability,especially for the classification and prediction of small limited samples showing out good *** the study,a group of 616 chemical compounds including 234 antibacterial compounds and 382 non-antibacterial compounds was used .Subsequently,a set of 198 molecular descriptors was calculated,including simple molecular properties descriptors,molecular connectivity and shape descriptors,electro-topological state descriptors,quantum chemical properties descriptors and geometrical properties descriptors which are used for representing molecular properties of chemical compounds.A 5-fold cross-validation and an independent evaluation set were used to train and evaluate the SVM classification model,*** the 5-fold cross-validation,the antibacterial and non-antibacterial compounds were arbitrarily divided into several groups,and then several compounds were selected randomly from each group to constitute training set and testing set respectively.A feature selection method,recursive feature elimination（RFE）,was used in order to automatically eliminate some redundant variable

关键词： Support vector machine(SVM) Antibacterial activity Molecular descriptors Recursive feature elimination(RFE)

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Chinese Chemical Letters 2025年第1期36卷 1-2页

作者： min-Hang Zhou Jun Jiang Wei-min He School of Chemistry and Chemical Engineering University of South ChinaHengyang 421001China

The synthesis ofα-amino acid from imines with different carbonyl sources is attractive for both synthetic organic and medicinal chemistry ***,which were easily available from the corresponding ketones and amines,were employed as one of the most ideal ***,cyanation and subsequent hydrolysis were required to install the carboxyl group^([1]).In these cases,the toxicity of the cyanation reagents limited its further synthetic applications in organic ***,metal activation of imine substrates to make the organometallic intermediate and trap CO_(2) to give the desiredα-amino acid were also developed by many groups(Scheme 1A).The utilization of stoiochiometric amounts of metal reagents was required to realize the ***,Yu reported a novel photocatalytic reductive carboxylation protocol for synthesis ofα-amino acid from imines with CO_(2)as the carbonyl source^([2]).

关键词： synthesis carbonyl photochemical

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