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A porous⁃layered aluminoborate built by mixed oxoboron clusters and AlO_(4)tetrahedra
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作者 CHEN Juan YANG Guoyu 《无机化学学报》 北大核心 2025年第1期193-200,共8页
An aluminoborate,Na_(2.5)Rb[Al{B_(5)O_(10)}{B_(3)O_(5)}]·0.5NO_(3)·H_(2)O(1),was synthesized under hydrothermal condition,which was built by mixed oxoboron clusters and AlO_(4)tetrahedra.In the structure,the... An aluminoborate,Na_(2.5)Rb[Al{B_(5)O_(10)}{B_(3)O_(5)}]·0.5NO_(3)·H_(2)O(1),was synthesized under hydrothermal condition,which was built by mixed oxoboron clusters and AlO_(4)tetrahedra.In the structure,the[B_(5)O_(10)]^(5-)and[B_(3)O_(7)]^(5-)clusters are alternately connected to form 1D[B_(8)O_(15)]_(n)^(6n-)chains,which are further linked by AlO_(4)units to form a 2D monolayer with 7‑membered ring and 10‑membered ring windows.Two adjacent monolayers with opposite orientations further form a porous‑layered structure with six channels through B—O—Al bonds.Compound 1 was characterized by single crystal X‑ray diffraction,powder X‑ray diffraction(PXRD),IR spectroscopy,UV‑Vis diffuse reflection spectroscopy,and thermogravimetric analysis(TGA),respectively.UV‑Vis diffuse reflectance analysis indicates that compound 1 shows a wide transparency range with a short cutoff edge of 201 nm,suggesting it may have potential application in UV regions.CCDC:2383923. 展开更多
关键词 hydrothermal synthesis aluminoborate mixed oxoboron cluster porous layer
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Ultrafine platinum clusters achieved by metal‑organic framework derived cobalt nanoparticle/porous carbon:Remarkable catalytic performance in dehydrogenation of ammonia borane
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作者 XIE Xinnan ZHANG Boyu +4 位作者 YANG Jianxun ZHONG Yi Osama Younis YANG Jianxiao YANG Xinchun 《无机化学学报》 北大核心 2025年第10期2095-2102,共8页
Ultrafine,highly dispersed Pt clusters were immobilized onto the Co nanoparticle surfaces by one-step pyrolysis of the precursor Pt(Ⅱ)-encapsulating Co-MOF-74.Owing to the small size effects of Pt clusters as well as... Ultrafine,highly dispersed Pt clusters were immobilized onto the Co nanoparticle surfaces by one-step pyrolysis of the precursor Pt(Ⅱ)-encapsulating Co-MOF-74.Owing to the small size effects of Pt clusters as well as the strongly enhanced synergistic interactions between Pt and Co atoms,the obtained Pt-on-Co/C400 catalysts exhib-ited excellent catalytic activity toward the hydrolysis of ammonia borane with an extremely high turnover frequency(TOF)value of 3022 min^(-1)at 303 K.Durability test indicated that the obtained Pt-on-Co/C400 catalysts possessed high catalytic stability,and there were no changes in the catalyst structures and catalytic activities after 10 cycles. 展开更多
关键词 ammonia borane hydrogen generation Pt cluster porous carbon metal-organic framework
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Generalized Energy-Based Fragmentation DLPNO-CCSD(T)Approach at Complete Basis Set Limit and Its Application to Benzene Clusters
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作者 Yan Sun Benkun Hong +1 位作者 Wei Li Shuhua Li 《Chinese Journal of Chemical Physics》 2025年第3期347-355,I0061-I0105,I0109,共55页
Accurate description of noncova-lent interactions in large systems is challenging due to the require-ment of high-level electron corre-lation methods.The generalized energy-based fragmentation(GEBF)approach,in conjunc... Accurate description of noncova-lent interactions in large systems is challenging due to the require-ment of high-level electron corre-lation methods.The generalized energy-based fragmentation(GEBF)approach,in conjunc-tion with the domain-based local pair natural orbital(DLPNO)method,has been applied to assess the average binding energies(ABEs)of large benzene clus-ters,specifically(C6H6)13,at the coupled cluster singles and doubles with perturbative triples correction[CCSD(T)]level and the complete basis set(CBS)limit.Utilizing GEBF-DLPNO-CCSD(T)/CBS ABEs as benchmarks,various DFT functionals were evaluated.It was found that several functionals with empirical dispersion correction,including M06-2X-D3,B3LYP-D3(BJ),and PBE-D3(BJ),provide accurate descriptions of the ABEs for(C6H6)13 clusters.Additionally,the M06-2X-D3 functional was used to calculate the ABEs and relative stabili-ties of(C6H6)n clusters for n=11,12,13,14,and 15 revealing that the(C6H6)13 cluster ex-hibits the highest relative stability.These findings align with experimental evidence suggest-ing that n=13 is one of the magic numbers for benzene clusters(C6H6)n,with n≤30. 展开更多
关键词 Generalized energy-based fragmentation approach Coupled cluster Complete basis set limit Benzene cluster Dispersion interactions
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HIV Pretreatment Drug Resistance and Transmission Clusters among Newly Diagnosed Patients in the China-Myanmar Border Region,2020–2023
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作者 Huan Liu Yuecheng Yang +6 位作者 Xing Duan Yichen Jin Yanfen Cao Yi Feng Chang Cai Hehe Zhao Houlin Tang 《Biomedical and Environmental Sciences》 2025年第7期840-847,共8页
Objective This study aimed to investigate the prevalence of HIV pretreatment drug resistance(PDR)and the transmission clusters associated with PDR-related mutations in newly diagnosed,treatmentnaive patients between 2... Objective This study aimed to investigate the prevalence of HIV pretreatment drug resistance(PDR)and the transmission clusters associated with PDR-related mutations in newly diagnosed,treatmentnaive patients between 2020 and 2023 in Dehong prefecture,Yunnan province,China.Methods Demographic information and plasma samples were collected from study participants.PDR was assessed using the Stanford HIV Drug Resistance Database.The Tamura-Nei 93 model within HIVTRACE was employed to compute pairwise matches with a genetic distance of 0.015 substitutions per site.Results Among 948 treatment-naive individuals with eligible sequences,36 HIV subtypes were identified,with unique recombinant forms(URFs)being the most prevalent(18.8%,178/948).The overall prevalence of PDR was 12.4%(118/948),and resistance to non-nucleotide reverse transcriptase inhibitors(NNRTIs),nucleotide reverse transcriptase inhibitors(NRTIs),and protease inhibitors(PIs)was10.7%,1.3%,and 1.6%,respectively.A total of 91 clusters were identified,among which eight showed evidence of PDR strain transmission.The largest PDR-associated cluster consisted of six CRF01_AE drugresistant strains carrying K103N and V179T mutations;five of these individuals had initial CD4^(+)cell counts<200 cells/μL.Conclusion The distribution of HIV subtypes in Dehong is diverse and complex.PDR was moderately prevalent(12.4%)between 2020 and 2023.Evidence of transmission of CRF01_AE strains carrying K103N and V179T mutations was found.Routine surveillance of PDR and the strengthening of control measures are essential to limit the spread of drug-resistance HIV strains. 展开更多
关键词 HIV Drug resistance SUBTYPE cluster analysis
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Unveiling the Formation and Electrochemical Properties of Nano-Clusters in Lithium Battery Electrolyte Induced by Nitrate Ion
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作者 Jingwei Zhang Jia Li +3 位作者 Yawen Li Kun Li Weiwei Xie Qing Zhao 《Energy & Environmental Materials》 2025年第4期116-123,共8页
LiNO_(3) is known to significantly enhance the reversibility of lithium metal batteries;however,the modification of solvation structures in various solvents and its further impact on the interface have not been fully ... LiNO_(3) is known to significantly enhance the reversibility of lithium metal batteries;however,the modification of solvation structures in various solvents and its further impact on the interface have not been fully revealed.Herein,we systematically studied the evolution of solvation structures with increasing LiNO_(3) concentration in both carbonate and ether electrolytes.The results from molecular dynamics simulations unveil that the Li^(+)solvation structure is less affected in carbonate electrolytes,while in ether electrolytes,there is a significant decrease of solvent molecules in Li^(+)coordination,and a larger average size of Li^(+)solvation structure emerges as LiNO_(3) concentration increases.Notably,the formation of large ion aggregates with size of several nanometers(nano-clusters),is observed in ether-based electrolytes at conventional Li^(+)concentration(1 M)with higher NO_(3)^(-) ratio,which is further proved by infrared spectroscopy and small-angle X-ray scattering experiments.The nano-clusters with abundant anions are endowed with a narrow energy gap of molecular orbitals,contributing to the formation of an inorganic rich electrode/electrolyte interphase that enhances the reversibility of lithium stripping/plating with Coulombic efficiency up to 99.71%.The discovery of nano-clusters elucidates the underlying mechanism linking ions/solvent aggregation states of electrolytes to interfacial stability in advanced battery systems. 展开更多
关键词 clusters electrolytes lithium-metal batteries MD simulations solvation structures
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Correlation Analysis Between Symptom Clusters and Quality of Life in Patients with Acute Exacerbation of Chronic Obstructive Pulmonary Disease
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作者 Wenjie Wang Na Wang +1 位作者 Yujiao Wang Dan Liu 《Journal of Clinical and Nursing Research》 2025年第8期43-52,共10页
Objective:This study aims to investigate the patterns of symptom occurrence in patients experiencing acute exacerbations of chronic obstructive pulmonary disease(AECOPD).It will explore the composition of symptom clus... Objective:This study aims to investigate the patterns of symptom occurrence in patients experiencing acute exacerbations of chronic obstructive pulmonary disease(AECOPD).It will explore the composition of symptom clusters and analyze the correlation between these clusters and health-related quality of life(HRQoL).Methods:A total of 207 patients with AE-COPD were surveyed from a tertiary grade A hospital.Data collection was conducted using three validated instruments:the Basic Information Questionnaire(BIQ),Disease Symptom Survey Questionnaire(MSAS),and Quality of Life Questionnaire(CAT).Statistical software SPSS 22.0 was used to analyze the correlation between symptom clusters and quality of life.Results:Exploratory factor analysis showed that five major symptom clusters existed in the patients,including the psycho-emotional symptom cluster,the sleep-related symptom cluster,the other side effects symptom cluster,the energy deficiency symptom cluster and the cough-loss of appetite symptom cluster,and the severity of the symptom clusters showed a significant negative correlation with the quality of life of the patients(P<0.05).Conclusion:Strengthening the comprehensive management of symptom clusters in patients with AE-COPD can help to effectively reduce the symptom burden of patients,and then significantly improve their quality of life. 展开更多
关键词 COPD Acute exacerbation Symptom cluster Quality of life
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Electro-functionalized 2D nitrogen-carbon nanosheets decorated with symbiotic cobalt single-atoms/clusters
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作者 Xinyan Zhou Sifan Qiao +7 位作者 Zhenzhen Zhao Meiqi Liu Kexin Song Fuxi Liu Nailin Yue Xiujuan Li Meng Zou Wei Zhang 《Journal of Energy Chemistry》 2025年第2期385-391,I0008,共8页
Two-dimensional(2D)materials loaded with single atoms and clusters are being set at the forefront of catalysis due to their distinctive geometric and electronic features.However,the usually-complicated synthesis proce... Two-dimensional(2D)materials loaded with single atoms and clusters are being set at the forefront of catalysis due to their distinctive geometric and electronic features.However,the usually-complicated synthesis procedures impede in-depth clarification of their catalytic mechanisms.To this end,herein we developed an efficient one-step dimension-reduction carbonization strategy,with which we successfully architected a highly-efficient catalyst for oxygen reduction reaction(ORR),featured with symbiotic cobalt single atoms and clusters decorated in two-dimensional(2D)ultra-thin(3.5 nm thickness)nitrogen-carbon nanosheets.The synergistic effects of the two components afford excellent oxygen reduction activity in alkaline media(E_(1/2)=0.823 V vs.RHE)and thereof a high power density(146.61 mW cm^(-2))in an assembled Zn-air battery.As revealed by theoretical calculations,the cobalt clusters can regulate electrons surrounding those individual atoms and affect the adsorption of intermediate species.As a consequence,the derived active sites of single cobalt atoms lead to a significant improvement of the ORR performance.Thus,our work may fuel interests to delicate architectu re of single atoms and clusters coexisting 2D support toward optimal electrocatalytic performance. 展开更多
关键词 Singleatoms and clusters Two-dimensional NANOSHEETS Carbon-Nitrogen Oxygen reduction reaction
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Channel competition in dissociation of ammonia clusters(n≤5)induced by femtosecond laser fields
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作者 Tao Yang Xinyu Zhang +5 位作者 Xing Li Wankai Li Menghao Wei Dongdong Zhang Lanhai He Dajun Ding 《Chinese Physics B》 2025年第3期355-359,共5页
We investigated the ionization and dissociation processes of ammonia clusters ranging from dimer to pentamer induced by 800-nm femtosecond laser fields.Time-of-flight(TOF)mass spectra of the ammonia clusters were reco... We investigated the ionization and dissociation processes of ammonia clusters ranging from dimer to pentamer induced by 800-nm femtosecond laser fields.Time-of-flight(TOF)mass spectra of the ammonia clusters were recorded over a range of laser intensities from 2.1×10^(12)W/cm^(2) to 5.6×10^(12)W/cm^(2).The protonated ion signals dominate the spectra,which is consistent with the stability of the geometric structures.The ionization and dissociation channels of ammonia clusters are discussed.The competition and switching among observed dissociation channels are revealed by analyzing the variations in the relative ionic yields of specific protonated and unprotonated clusters under different laser intensities.These results indicate that the ionization of the neutral multiple-ammonia units,produced through the dissociation of cluster ions,may start to contribute,as well as the additional processes to consume protonated ions and/or produce unprotonated ions induced by the femtosecond laser fields when the laser intensity is above^4×10^(12)W/cm^(2).These findings provide deeper insights into the ionization and dissociation dynamics in multi-photon ionization experiments involving ammonia clusters. 展开更多
关键词 ammonia cluster ionization and dissociation femtosecond laser
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Unveiling the unexpected sinking and embedding dynamics of surface supported Mo/S clusters on 2D MoS_(2)with active machine learning
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作者 Luneng Zhao Yanhan Ren +4 位作者 Xiaoran Shi Hongsheng Liu Zhigen Yu Junfeng Gao Jijun Zhao 《Smart Molecules》 2025年第1期46-54,共9页
Surface-supported clusters forming by aggregation of excessive adatoms could be the main defects of 2D materials after chemical vapor deposition.They will significantly impact the electronic/magnetic properties.Moreov... Surface-supported clusters forming by aggregation of excessive adatoms could be the main defects of 2D materials after chemical vapor deposition.They will significantly impact the electronic/magnetic properties.Moreover,surface supported atoms are also widely explored for high active and selecting catalysts.Severe deformation,even dipping into the surface,of these clusters can be expected because of the very active edge of clusters and strong interaction between supported clusters and surfaces.However,most models of these clusters are supposed to simply float on the top of the surface because ab initio simulations cannot afford the complex reconstructions.Here,we develop an accurate graph neural network machine learning potential(MLP)from ab initio data by active learning architecture through fine-tuning pre-trained models,and then employ the MLP into Monte Carlo to explore the structural evolutions of Mo and S clusters(1-8 atoms)on perfect and various defective MoS2 monolayers.Interestingly,Mo clusters can always sink and embed themselves into MoS2 layers.In contrast,S clusters float on perfect surfaces.On the defective surface,a few S atoms will fill the vacancy and rest S clusters float on the top.Such significant structural reconstructions should be carefully taken into account. 展开更多
关键词 active learning machine learning potential Monte Carlo surface-supported clusters
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Platinum clusters stabilized by zincosilicate zeolite for efficient propane dehydrogenation
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作者 Hao Liu Ying Zhang +11 位作者 Liyang Liu Tianxiang Chen Xingcong Zhang Peng Hu Chao Xiong Jie Zhou Hao Zhang Lihui Dong Tsz Woon Benedict Lo Bing Nan Xiaohui He Hongbing Ji 《Chinese Journal of Catalysis》 2025年第4期208-219,共12页
Dispersing metals from nanoparticles to clusters is often achieved using ligand protection methods,which exhibit unique properties such as suppressing structure-sensitive side reactions.However,this method is limited ... Dispersing metals from nanoparticles to clusters is often achieved using ligand protection methods,which exhibit unique properties such as suppressing structure-sensitive side reactions.However,this method is limited by the use of different metal precursor salts corresponding to different ligands.An alternative approach,the ion exchange(IE)method,can overcome this limitation to some extent.Nevertheless,there is still an urgent need to address the stabilization of metals(especially precious metals)by using IE method.Here,we reported a Pt cluster catalyst prepared mainly by anchoring Pt atoms via O located near the framework Zn in zincosilicate zeolites and riveted by zeolite surface rings after reduction(reduced Pt/Zn-3-IE).The catalyst can achieve an initial propane conversion of 26%in a pure propane atmosphere at 550℃and shows little deactivation even after 7.5 d of operation.Moreover,the alteration of catalyst by the introduction of framework Zn was also highlighted and interpreted. 展开更多
关键词 Zincosilicate zeolite Acid-site identification Rivet effect Pt clusters Propane dehydrogenation
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Exploring core symptoms and symptom clusters among patients with neuromyelitis optica spectrum disorder: A network analysis
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作者 Hao Liang Jiehan Chen +4 位作者 Lixin Wang Zhuyun Liu Haoyou Xu Min Zhao Xiaopei Zhang 《International Journal of Nursing Sciences》 2025年第2期152-160,共9页
Objectives To identify core symptoms and symptom clusters in patients with neuromyelitis optica spectrum disorder(NMOSD)by network analysis.Methods From October 10 to 30,2023,140 patients with NMOSD were selected to p... Objectives To identify core symptoms and symptom clusters in patients with neuromyelitis optica spectrum disorder(NMOSD)by network analysis.Methods From October 10 to 30,2023,140 patients with NMOSD were selected to participate in this online questionnaire survey.The survey tools included a general information questionnaire and a self-made NMOSD symptoms scale,which included the prevalence,severity,and distress of 29 symptoms.Cluster analysis was used to identify symptom clusters,and network analysis was used to analyze the symptom network and node characteristics and central indicators including strength centrality(r_(s)),closeness centrality(r_(c))and betweeness centrality(r_(b))were used to identify core symptoms and symptom clusters.Results The most common symptom was pain(65.7%),followed by paraesthesia(65.0%),fatigue(65.0%),easy awakening(63.6%).Regarding the burden level of symptoms,pain was the most burdensome symptom,followed by paraesthesia,easy awakening,fatigue,and difficulty falling asleep.Six clusters were identified:somatosensory,motor,visual,and memory symptom clusters,bladder and rectum symptom clusters,sleep symptoms clusters,and neuropsychological symptom clusters.Fatigue(r_(s)=12.39,r_(b)=68.00,r_(c)=0.02)was the most central and prominent bridge symptom,and motor symptom cluster(r_(s)=2.68,r_(c)=0.10)was the most central symptom cluster among the six clusters.Conclusions Our study demonstrated the necessity of symptom management targeting fatigue,pain,and motor symptom cluster in patients with NMOSD. 展开更多
关键词 Neuromyelitis optica spectrum disorder Network analysis SYMPTOM Symptom clusters NURSING
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Dye-stabilized atomically precise copper clusters for enhanced photocatalytic hydrogen evolution
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作者 Yan-Ling Li Yue Xu +2 位作者 Chen-Hong Wang Rui Wang Shuang-Quan Zang 《Chinese Chemical Letters》 2025年第10期318-322,共5页
Metal nanoclusters with well-defined atomic structures offer significant promise in the field of catalysis due to their sub-nanometer size and tunable organic-inorganic hybrid structural features.Herein,we successfull... Metal nanoclusters with well-defined atomic structures offer significant promise in the field of catalysis due to their sub-nanometer size and tunable organic-inorganic hybrid structural features.Herein,we successfully synthesized an 11-core copper(Ⅰ)-alkynyl nanocluster(Cu11),which is stabilized by alkynyl ligands derived from a photosensitive rhodamine dye molecule.Notably,this Cu11cluster exhibited excellent photocatalytic hydrogen evolution activity(8.13 mmol g-1h-1)even in the absence of a mediator and noble metal co-catalyst.Furthermore,when Cu11clusters were loaded onto the surface of TiO_(2)nanosheets,the resultant Cu11@TiO_(2)nanocomposites exhibited a significant enhancement in hydrogen evolution efficiency,which is 60 times higher than that of pure TiO_(2)nanosheets.The incorporation of Cu11clusters within the Cu11@TiO_(2)effectively inhibits the recombination of photogenerated electrons and holes,thereby accelerating the charge separation and migration in the composite material.This work introduces a novel perspective for designing highly active copper cluster-based photocatalysts. 展开更多
关键词 Copper cluster Atomically precise NANOCOMPOSITES Photoactive rhodamine-based ligand Photocatalytic hydrogen evolution
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XGboost for Predicting Chemical Abundances of Open Clusters in LAMOST DR11 LRS
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作者 R.Zhang Jianxing Chen +4 位作者 Chengyuan Wu Luqian Wang Shuai Zha Sufen Guo Zhanwen Han 《Research in Astronomy and Astrophysics》 2025年第3期223-232,共10页
The 11th data release of the LAMOST survey provides fundamental stellar parameters but lacks detailed abundance measurements forα-elements,which are crucial for understanding stellar populations and Galactic chemical... The 11th data release of the LAMOST survey provides fundamental stellar parameters but lacks detailed abundance measurements forα-elements,which are crucial for understanding stellar populations and Galactic chemical evolution.In this study,we derive the abundances of oxygen(O),magnesium(Mg),silicon(Si),calcium(Ca),and titanium(Ti)for over 6.8 million stars using LAMOST DR11 low-resolution spectra.To ensure reliable measurements,we select 760 open clusters spanning a broad range of ages and apply Monte Carlo sampling for accurate abundance estimates.Additionally,we utilize over 30,000 stars from the GALAH DR4 catalog to train an XGBoost model for extractingα-element abundances from LAMOST DR11 spectra.Bayesian linear regression is employed to analyze the compositional distribution across the Galactic disk and infer chemical gradients as a function of Galactocentric distance.Our results indicate a general increase in chemical abundances with Galactocentric distance,with oxygen showing the steepest gradient.Our results confirm the overall increase ofα-element abundances with Galactocentric distance,consistent with previous studies,while minor discrepancies in Mg,Ca,and Ti gradients likely arise from differences in sample selection,observational sensitivity,or Galactic enrichment processes. 展开更多
关键词 stars abundances-stars atmospheres-Galaxy abundances-Galaxy disk-(Galaxy )open clusters and associations general
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Correction:Transition Metal Carbonitride MXenes Anchored with Pt Sub‑nanometer Clusters to Achieve High‑Performance Hydrogen Evolution Reaction at All pH Range
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作者 Zhihao Lei Sajjad Ali +18 位作者 CI Sathish MuhammadIbrar Ahmed Jiangtao Qu RongkunZheng Shibo Xi Xiaojiang Yu M.B.H.Breese Chao Liu Jizhen Zhang Shuai Qi Xinwei Guan Vibin Perumalsamy Mohammed Fawaz Jae‑Hun Yang Mohamed Bououdina Kazunari Domen Ajayan Vinu Liang Qiao Jiabao Yi 《Nano-Micro Letters》 2025年第7期452-452,共1页
Correction to:Nano-Micro Letters(2025)17:123 https://doi.org/10.1007/s40820-025-01654-y Following publication of the original article[1],the authors reported that Dr.Mohamed Bououdina’s affiliation needed to be corre... Correction to:Nano-Micro Letters(2025)17:123 https://doi.org/10.1007/s40820-025-01654-y Following publication of the original article[1],the authors reported that Dr.Mohamed Bououdina’s affiliation needed to be corrected from 1 to 2.The correct author affiliation has been provided in this Correction and the original article[1]has been corrected. 展开更多
关键词 CARBONITRIDES hydrogen evolution reaction Pt sub nanometer clusters transition metals
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Ligand-engineered octanuclear bismuth-oxo clusters with exposed active sites for enhanced CO_(2)-to-HCOOH electroreduction
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作者 Hao-Nan Zhou Lan-Yan Li +3 位作者 Hong-Bing Mo Yi-Xin Li Jun Yan Chao Liu 《Chinese Chemical Letters》 2025年第10期661-665,共5页
The atomic-level exploration of structure-property correlations poses significant challenges in establishing precise design principles for electrocatalysts targeting efficient CO_(2)conversion.This study demonstrates ... The atomic-level exploration of structure-property correlations poses significant challenges in establishing precise design principles for electrocatalysts targeting efficient CO_(2)conversion.This study demonstrates how controlled exposure of metal sites governs CO_(2)electroreduction performance through two octanuclear bismuth-oxo clusters with distinct architectures.The Bi_(8)-DMF cluster,constructed using tert–butylthiacalix[4]arene(TC4A)as the sole ligand,features two surface-exposed Bi active sites,while the dual-ligand Bi_(8)-Fc(with TC4A/ferrocene carboxylate)forms a fully encapsulated structure.Electrocatalytic tests reveal Bi_(8)-DMF achieves exceptional formate selectivity(>90%Faradaic efficiency)across a broad potential window(-0.9 V to-1.6 V vs.RHE)with 20 h stability,outperforming Bi_(8)-Fc(60%efficiency at-1.5 V).Theoretical calculations attribute Bi_(8)-DMF's superiority to exposed Bi sites that stabilize the critical*OCHO intermediate via optimized orbital interactions.This work provides crucial guidance for polynuclear catalyst design:moderate exposure of metal active sites significantly enhances CO_(2)reduction performance. 展开更多
关键词 Nanocluster Bismuth-oxo clusters CO_(2)electroreduction Formic acid Ligand engineering
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Surface confinement of sub-1 nm Pt nanoclusters on 1D/2D NiO nanotubes/nanosheets as an effective electrocatalyst for urea-assisted energy-saving hydrogen production
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作者 Jiaxin Li Yan Lv +5 位作者 Xueyan Wu Xinyu Guo Zhuojun Yang Jixi Guo Tianhua Zhou Dianzeng Jia 《Chinese Journal of Catalysis》 2025年第2期203-218,共16页
To address the high cost and limited electrochemical endurance of Pt-based electrocatalysts,the appropriate introduction of transition metal-based compounds as supports to disperse and anchor Pt species offers a promi... To address the high cost and limited electrochemical endurance of Pt-based electrocatalysts,the appropriate introduction of transition metal-based compounds as supports to disperse and anchor Pt species offers a promising approach for improving catalytic efficiency.In this study,sub-1 nm Pt nanoclusters were uniformly confined on NiO supports with a hierarchical nanotube/nanosheet structure(Pt/NiO/NF)through a combination of spatial domain confinement and annealing.The resulting catalyst exhibited excellent electrocatalytic activity and stability for hydrogen evolution(HER)and urea oxidation reactions(UOR)under alkaline conditions.Structural characterization and density functional theory calculations demonstrated that sub-1 nm Pt nanoclusters were immobilized on the NiO supports by Pt–O–Ni bonds at the interface.The strong metal-support interaction induced massive charge redistribution around the heterointerface,leading to the formation of multiple active sites.The Pt/NiO/NF catalyst only required an overpotential of 12 and 136 mV to actuate current densities of 10 and 100 mA cm^(-2) for the HER,respectively,and maintained a voltage retention of 96%for 260 h of continuous operation at a current density of 500 mA cm^(-2).Notably,in energy-efficient hydrogen production systems coupled with the HER and UOR,the catalyst required cell voltages of 1.37 and 1.53 V to drive current densities of 10 and 50 mA cm^(-2),respectively—approximately 300 mV lower than conventional water electrolysis systems.This study presents a novel pathway for designing highly efficient and robust sub-nanometer metal cluster catalysts. 展开更多
关键词 Metal-support interaction Sub-nanometric cluster Hydrogen evolution reaction Size engineering Urea oxidation reaction
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Electronic interactions between neighboring functionalized vip Sb single atoms and Pt clusters enhance CO tolerance
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作者 Wenkang Miao Ronghui Hao +10 位作者 Lu Gan Wanyin Xu Zihan Wang Wenxin Lin Heguang Liu Yinchun Lyu Qianqian Li Jinyang Xi Anmin Nie Jinsong Wu Hongtao Wang 《Journal of Energy Chemistry》 2025年第2期733-743,I0016,共12页
Platinum-based(Pt)catalysts are notoriously susceptible to deactivation in industrial chemical processes due to carbon monoxide(CO)poisoning.Overcoming this poisoning deactivation of Pt-based catalysts while enhancing... Platinum-based(Pt)catalysts are notoriously susceptible to deactivation in industrial chemical processes due to carbon monoxide(CO)poisoning.Overcoming this poisoning deactivation of Pt-based catalysts while enhancing their catalytic activity,selectivity,and durability remains a major challenge.Herein,we propose a strategy to enhance the CO tolerance of Pt clusters(Pt_n)by introducing neighboring functionalized vip single atoms(such as Fe,Co,Ni,Cu,Sb,and Bi).Among them,antimony(Sb)single atoms(SAs)exhibit significant performance enhancement,achieving 99%CO selectivity and 33.6%CO_(2)conversion at 450℃,Experimental results and density functional theory(DFT)calculations indicate the optimization arises from the electronic interaction between neighboring functionalized Sb SAs and Pt clusters,leading to optimal 5d electron redistribution in Pt clusters compared to other functionalized vip single atoms.The redistribution of 5d electrons weaken both theσdonation andπbackdonation interactions,resulting in a weakened bond strength with CO and enhancing catalyst activity and selectivity.In situ environmental transmission electron microscopy(ETEM)further demonstrates the exception thermal stability of the catalyst,even under H_(2)at 700℃.Notably,the functionalized Sb SAs also improve CO tolerance in various heterogenous catalysts,including Co/CeO_(2),Ni/CeO_(2),Pt/Al_(2)O_(3),and Pt/CeO_(2)-C.This finding provides an effective approach to overcome the primary challenge of CO poisoning in Pt-based catalysts,making their broader applications in various industrial catalysts. 展开更多
关键词 Functionalized vip single atoms Pt cluster CO tolerance Electronic effect In-situ TEM
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Noble metal clusters substitution in porous Ni substrate renders high mass-specific activities toward oxygen evolution reaction and methanol oxidation reaction
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作者 Fenglin Wang Chengwei Kuang +6 位作者 Zhicheng Zheng Dan Wu Hao Wan Gen Chen Ning Zhang Xiaohe Liu Renzhi Ma 《Chinese Chemical Letters》 2025年第6期714-719,共6页
The sluggish reaction kinetics of the oxygen evolution reaction(OER)and methanol oxidation reaction(MOR)remain obstacles to the commercial promotion of water splitting and direct methanol fuel cells.Considering the vi... The sluggish reaction kinetics of the oxygen evolution reaction(OER)and methanol oxidation reaction(MOR)remain obstacles to the commercial promotion of water splitting and direct methanol fuel cells.Considering the vital role of noble metals in electrocatalytic activity,this work focuses on the rational synthesis of Ni-noble metal composite nanocatalysts for overcoming the drawbacks of high cost and susceptible oxidized surfaces of noble metals.The inherent catalytic activity is improved by the altered electronic structure and effective active sites of the catalyst induced by the size effect of noble metal clusters.In particular,a series of Ni-noble metal nanocomposites are successfully synthesized by partially introducing noble metal into Ni with porous interfacial defects derived from Ni-Al layered double hydroxide(LDH).The Ni_(10)Pd_(1)nanocomposite exhibits high OER catalytic activity with an overpotential of 0.279 V at 10 m A/cm^(2),surpassing Ni_(10)Ag_(1)and Ni_(10)Au_(1)counterparts.Furthermore,the average diameter of Pd clusters gradually increases from 5.57 nm to 44.44 nm with the increased proportion of doped Pd,leading to the passivation of catalytic activity due to the exacerbated surface oxidation of Pd in the form of Pd^(2+).After optimization,Ni_(10)Pd_(1)delivers significantly enhanced OER and MOR electroactivities and long-term stability compared to that of Ni_(2)Pd_(1),Ni_(1)Pd_(1)and Ni_(1)Pd_(2),which is conducive to the effective utilization of Pd and alleviation of surface oxidation. 展开更多
关键词 Size effect Pd cluster Mass activity Oxygen evolution reaction Methanol oxidation reaction
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Correction to:Ultra-fine Cu clusters decorated hydrangea-like titanium dioxide for photocatalytic hydrogen production
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作者 Ya-Jie Feng Yang Wang +7 位作者 Kai-Wen Wang Jiang-Ping Ma You-Yu Duan Jie Liu Xu Lu Bin Zhang Guo-Yu Wang Xiao-Yuan Zhou 《Rare Metals》 2025年第3期2140-2141,共2页
Correction to:Rare Met.https://doi.org/10.1007/s12598-021-01815-z In the original publication,Fig.5 was published with few mistakes.The correct version of Fig.5 is given in this correction.
关键词 hydrangea titanium dioxide figure correction CORRECTION photocatalytic hydrogen production ultra fine Cu clusters
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Exploring COPD Patient Clusters and Associations with Health-Related Quality of Life Using A Machine Learning Approach:A Nationwide Cross-Sectional Study
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作者 Chao Wang Fengyun Yu +9 位作者 Zhong Cao Ke Huang Qiushi Chen Pascal Geldsetzer Jinghan Zhao Zhoude Zheng Till Bärnighausen Ting Yang Simiao Chen Chen Wang 《Engineering》 2025年第7期220-228,共9页
Chronic obstructive pulmonary disease(COPD)is a complex condition marked by considerable interindividual heterogeneity.Comorbidities exacerbate this variability,worsening disease severity and reducing health-related q... Chronic obstructive pulmonary disease(COPD)is a complex condition marked by considerable interindividual heterogeneity.Comorbidities exacerbate this variability,worsening disease severity and reducing health-related quality of life(HRQoL).Despite the high prevalence of COPD in China,COPD patient clusters remain poorly characterized.This study aimed to identify and validate clusters of Chinese patients with COPD,characterized primarily by comorbidity profiles,using cluster analysis.This cross-sectional,multicenter cohort study used data from the Chinese Enjoying Breathing Program(2020–2023).HRQoL was measured using the EuroQol five dimension(EQ-5D).Dimension reduction was performed via multiple correspondence analysis on 31 variables,including indicators of 27 comorbidities and four sociodemographic or health-related characteristics.Unsupervised machine learning algorithms,K-means++,and hierarchical clustering identified distinct clusters.Robustness was assessed using random forest classification.Logistic regression evaluated the association between cluster membership and EQ-5D outcomes.Among 11145 patients,59.4%had comorbidities.Four clusters emerged:young male smokers,biomass-exposed females,respiratory comorbidity,and elderly multimorbid.The last two clusters had notably lower HRQoL.Cluster analysis identified four clinically meaningful COPD patient clusters based on comorbidities and risk profiles,each with distinct HRQoL outcomes.These findings support targeted public health interventions and integrated care strategies for COPD management. 展开更多
关键词 Chronic obstructive pulmonary disease COMORBIDITY cluster analysis Health-related quality of life Public health
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