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Growing Together——Villages in Zhejiang form clusters for common development
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作者 LIU TING 《ChinAfrica》 2026年第2期22-24,共3页
Villager Pan Chunlin is witnessing a boom in his homestay business.More and more visitors are coming to his village,Yucun Village in Anji County,Huzhou City,Zhejiang Province.
关键词 Huzhou city Zhejiang province VILLAGES VISITORS Yucun village clusters common development homestay business
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Iso-Nanozymes of Atomically Precise Copper Nanoclusters
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作者 Jing Sun Mengke Wang +13 位作者 Zong-Jie Guan Yunqing Kang Xueli Sang Yisheng Wang Rong Jing Xuekun Gong Xiaoxuan Xu Chengrui Xin Simin Li Yusuke Yamachi Nanfeng Zheng Xiyun Yan Qingxiang Guo Hui Shen 《Aggregate》 2026年第2期115-124,共10页
Nanozymes,a promising class of enzyme mimics based on nanostructures,have attracted considerable research interest.However,in sharp contrast to the structural precision of natural enzymes,most nanozymes are poorly def... Nanozymes,a promising class of enzyme mimics based on nanostructures,have attracted considerable research interest.However,in sharp contrast to the structural precision of natural enzymes,most nanozymes are poorly defined structurally.The absence of nanozyme systems that mimic natural isoenzymes-which catalyze similar reactions despite slight differences in their chemical structures-has particularly hindered the understanding of their structure-performance relationships.Such nanozyme analogues,termed iso-nanozymes,remain largely unexplored.Here,we report the first pair of iso-nanozymes.Two analogous copper nanoclusters-[Cu_(32)(SC_(2)H_(5))_(16)(PPh_(3))_(8)Cl_(9)]^(+) (Cu_(32))and[Cu_(30)(SC_(2)H_(5))_(16)(PPh_(3))_(6)Cl_(9)]^(+) (Cu_(30))-were synthesized and structurally characterized.Single-crystal X-ray diffraction analysis reveals that Cu_(30) possesses an identical metal framework and ligand types as Cu_(32),with a comparable ligand distribution.The only structural difference is the absence of two PPh_(3)Cu^(+) units in Cu_(30),which results in a substantial enhancement of its catalytic performance in the horseradish peroxidase-mimicking reaction.Under identical conditions,the specific activity(SA)of the Cu_(30) nanozyme is approximately 6.5 times higher than that of Cu_(32).Density functional theory calculations indicate that the notable difference in the SA between the two cluster nanozymes is attributed to variations in adsorption energies,which stem from their different geometric and electronic structures.This study not only introduces the novel concept of iso-nanozymes using atomically precise metal nanoclusters,but also establishes a model system for investigating the critical influence of nanozyme structure,down to the atomic level,on catalytic efficiency.These findings are anticipated to inspire further research interest in atomically precise metal nanoclusters within the nanozyme community. 展开更多
关键词 CATALYSTS crystal structure iso-nanozyme metal clusters structure-performance relationships
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Evolution Characteristics and Driving Mechanism of‘Bottom-up’and‘Top-down’Endogenous Automobile Industry Clusters:A Comparative Study in Taizhou and Wuhu,China
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作者 JIANG Haining ZHANG Jun +1 位作者 CHEN Jiaqi JIN Xingxing 《Chinese Geographical Science》 2026年第1期34-49,共16页
Bottom-up and top-down endogenous automobile clusters exhibit distinct evolutionary traits and driving mechanisms,yet their comparative analysis remains understudied.Therefore,using Taizhou automobile industry cluster... Bottom-up and top-down endogenous automobile clusters exhibit distinct evolutionary traits and driving mechanisms,yet their comparative analysis remains understudied.Therefore,using Taizhou automobile industry cluster(TAIC)and Wuhu automobile industry cluster(WAIC)as cases,using historical statistical data and field interview data from the 1980s to 2023,combined with qualitative research methods of thematic and diachronic analysis,and quantitative research methods of social network analysis,we compare both endogenous automobile clusters’evolutionary traits and driving mechanisms.The results confirm both clusters undergo multi-scale spatial reconfiguration,organizational complexification,and intelligent networking technological transformation,yet diverge fundamentally:TAIC evolves through market-driven progressive expansion,transitioning from single to dual-core structures via private enterprise networking,with innovation following market-integrated logic and institutional thickness built on demand-driven evolution.Conversely,WAIC follows planned expansion,maintaining state-led hierarchical single-core stability through policy-driven breakthrough innovation and supply-dominated institutional construction-though both ultimately require formal-informal system synergy.Their coevolution is driven by dynamic interactions of path dependence(weakening influence),learning-innovation(strengthening influence),and relationship selection(inverted U-shaped trajectory),with divergent development paths rooted in TAIC’s grassroots self-organization genes versus WAIC’s top-level design genes,amplified by core enterprises’strategic disparities.The research findings can not only provide decision-making support for China’s industrial upgrading,but also contribute China’s insights to global economic governance. 展开更多
关键词 endogenous automobile industrial clusters evolutionary characteristics driving mechanism Taizhou Wuhu China
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Electroacupuncture for Managing Chemotherapy-Induced Gastrointestinal Symptom Clusters in Patients With Breast Cancer:Study Protocol for a Randomized Controlled Trial
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作者 Xinlong Tao Zhen Liu +19 位作者 Miaozhou Wang Dengfeng Ren Fuxing Zhao Hongbin Wang Guowang Yang Ganlin Zhang Zitao Li Zhilin Liu Shifen Huang Yongzhi Chen Mengting Da Xiaoyan Ma Hongxia Liang Yongxin Li Yinyin Ye Yonghui Zheng Xiao Liang Guoshuang Shen Xiaorong Bai Jiuda Zhao 《Health Care Science》 2026年第1期85-94,共10页
Introduction:Chemotherapy-induced gastrointestinal symptom clusters in breast cancer impair quality of life and treatment adherence,yet lack effective interventions.While acupuncture mitigates isolated chemotherapy-in... Introduction:Chemotherapy-induced gastrointestinal symptom clusters in breast cancer impair quality of life and treatment adherence,yet lack effective interventions.While acupuncture mitigates isolated chemotherapy-induced symptoms,its mechanisms for multi-symptom clusters remain unclear.This study evaluates electroacupuncture's efficacy and explores its biological mechanisms in managing these clusters.Methods:This prospective,multicenter,block-randomized,double-blind,sham-controlled trial will enroll 388 patients with breast cancer undergoing neoadjuvant/adjuvant chemotherapy,to be randomly assigned(1:1)to electroacupuncture or sham electro-acupuncture groups.Both groups will receive the standard quadruple antiemetic regimen combined with electroacupuncture or sham intervention.The primary endpoint is the incidence of chemotherapy-induced gastrointestinal symptom clusters within 120 h after chemotherapy.Secondary endpoints include improvement in gastrointestinal symptom clusters post-first chemotherapy cycle,nausea-free rates during acute and delayed phases,vomiting-free rates during overall,acute,and delayed phases,complete response rate,complete protection rate,and quality of life.Adverse events will be documented throughout the study.Discussion:This study will assess the efficacy and safety of electroacupuncture in alleviating chemotherapy-induced gastro-intestinal symptom clusters in patients with breast cancer.By integrating multi-omics analyses,we aim to elucidate the biological mechanisms underlying its therapeutic effects.The findings may offer a robust clinical foundation for optimizing symptom cluster management in cancer care.Trial Registration:Clinical Trials ID:NCT06952920.Date of registration:April 16,2025.Prospectively registered.URL of Trial Registry Record:https://clinicaltrials.gov/study/NCT06952920cond=NCT06952920&rank=1. 展开更多
关键词 breast cancer chemotherapy-induced gastrointestinal symptom clusters ELECTROACUPUNCTURE standard quadruple antiemetic therapy
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Noncovalent Interaction-Mediated Space Charge Transition Facilitated Isolated Copper(I)-Iodide Clusters:Enabling High-Resolution X-Ray Imaging and Dynamic Encryption
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作者 Zhao-Xing Gao Wen-Fei Wang +3 位作者 Mian-He Xu Shuai-Hua Wang Fa-Kun Zheng Guo-Cong Guo 《Aggregate》 2026年第2期241-249,共9页
The exploration of solvent-driven reversible structural transformation in clusters is crucial for advanced stimulus-responsive optical applications and understanding of structure-property relationships.Herein,we repor... The exploration of solvent-driven reversible structural transformation in clusters is crucial for advanced stimulus-responsive optical applications and understanding of structure-property relationships.Herein,we report a solvent-driven reversible trans-formation between two copper(I)clusters:[Cu(totp)(CH_(3)CN)_(3)][Cu_(2)I_(3)(totp)(DPPPy)]·CH_(3)CN 1 and Cu_(4)I_(4)(DPPPy)_(2)·0.5CH_(2)Cl_(2)2(totp=tri-o-tolylphosphine,DPPPy=2-[diphenylphosphino]pyridine).X-ray radioluminescence and encryption applications were studied based on structure-dependent photophysical properties difference.The noncovalent interaction-mediated space charge transition between isolated ion units of 1 enables more efficient thermally activated delayed fluorescence by reverse intersystem crossing,accounting for structure-dependent luminescence.Notably,compared to 2,1 exhibits a higher scintillation light yield of 14832 photons MeV^(-1),exceeding that of the commercial scintillator Bi_(4)Ge_(3)O_(12)(8000 photons MeV^(-1)),and a low X-ray detection limit of 22.49 nGy s^(-1),far below the typical diagnostic dose(5.5μGy s^(-1)).Furthermore,scintillating film fabricated by 1 achieves X-ray imaging with a high spatial resolution of 16 lp/mm.The reversible structural interconversion enables solvent-responsive luminescent switches,and thus,the dynamic encryption system capable of multistage decryption was developed.This work not only offers new insight into solvent-regulated clusters transformations but also provides a promising strategy for developing high-performance copper(I)clusters-based scintillators and stimulus-responsive optical devices. 展开更多
关键词 copper(I)-iodide clusters information encryption solvent-driven structural transformation X-ray imaging
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Onsager vortex clusters on a sphere
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作者 Jiawen Chen Xiaoquan Yu 《Communications in Theoretical Physics》 2026年第1期139-152,共14页
We study Onsager vortex clustered states in a shell-shaped superfluid containing a large number of quantum vortices.In the incompressible limit and at low temperatures,the relevant problem can be boiled down to the st... We study Onsager vortex clustered states in a shell-shaped superfluid containing a large number of quantum vortices.In the incompressible limit and at low temperatures,the relevant problem can be boiled down to the statistical mechanics of neutral point vortices confined on a sphere.We analyze rotation-free vortex-clustered states within the mean-field theory in the microcanonical ensemble.We find that the sandwich state,which involves the separating of vortices with opposite circulation and the clustering of vortices with the same circulation around the poles and the equator,is the maximum entropy vortex distribution,subject to a zero angular momentum constraint.The dipole moment vanishes for the sandwich state and the quadrupole tensor serves as an order parameter to characterize the vortex cluster structure.For a given finite angular momentum,the equilibrium vortex distribution forms a dipole structure,i.e.,vortices with opposite sign are separated and accumulate around the south and north poles,respectively.The conditions for the onset of clustering and the exponents associated with the quadrupole moment and the dipole moment as functions of energy are obtained within the mean field theory.At large energies,we obtain asymptotically exact vortex density distributions using the stereographic projection method,yielding the parameter bounds for the vortex clustered states.The analytical predictions are in excellent agreement with microcanonical Monte Carlo simulations. 展开更多
关键词 Onsager vortex clusters negative temperature states shell-shaped superfluids
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Interscale analysis of sediment clusters amid turbulence 被引量:1
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作者 Wai Hong Ronald Chan Ahmed Elnahhas +3 位作者 Hanul Hwang Lucy J.Brown Andrew J.Banko S.Balachandar 《Acta Mechanica Sinica》 2026年第1期73-80,共8页
Noncohesive particle clusters are identified and tracked in turbulent flows to determine the breakdown and time evolution of cluster statistics and their implications for interscale mass transfer,which has connections... Noncohesive particle clusters are identified and tracked in turbulent flows to determine the breakdown and time evolution of cluster statistics and their implications for interscale mass transfer,which has connections to the classical turbulent energy cascade and its mass cascade counterpart running in parallel.In particular,the formation and dynamics of sediment and larvae clusters are of interest to coral larvae settlement in coastal regions and particularly the resilience of green-gray coastal protection solutions.Analogous cluster behavior is relevant to cloud microphysics and precipitation initiation,radiation transport and light transmission through colloids and suspensions,heat and mass transfer in particle-laden flows,and viral and pollutant transmission.Following a comparison between various clustering techniques,we adopt a density-based cluster identification algorithm based on its simplicity and efficiency,where particles are clustered based on the number of neighboring particles in their individual spheres of influence.We establish parallels with lattice-based percolation theory,as evident in the power-law scaling of the cluster size distribution near the percolation threshold.The degree of discontinuity of the phase transition associated with this percolation threshold is observed to broaden with larger Stokes numbers and thereby large-scale clustering.The sensitivity of our findings to the employed clustering algorithm is discussed.A novel cluster tracking algorithm is deployed to determine the interscale transfer rate along the particle-number phase-space dimension via accounting of cluster breakup and merger events,extending previous work on the bubble breakup cascade beneath surface breaking waves.Our findings shed light on the interaction between particle clusters and their carrier turbulent flows,with an eye toward transport models incorporating cluster characteristics and dynamics. 展开更多
关键词 Particle-laden flows Particle-laden turbulence Sediment transport Computational fluid dynamics Multiphase turbulence Particle clustering Percolation theory
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The five major textile and apparel industry clusters in Xinjiang have achieved an output value exceeding 220 billion yuan
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作者 Qiu Shuchen 《China Textile》 2026年第1期34-35,共2页
In the Tianshan region,a complete textile industry chain has been established,covering the entire process from cotton cultivation and chemical fiber production,through spinning,weaving,dyeing,and finishing,and further... In the Tianshan region,a complete textile industry chain has been established,covering the entire process from cotton cultivation and chemical fiber production,through spinning,weaving,dyeing,and finishing,and further extending to apparel,home textiles,and industrial textiles.In November 2025,the first list of five characteristic textile and apparel industry clusters in Xinjiang was officially announced,marking a new stage in the clustering of Xinjiang's textile and apparel industry.Data shows that the total output value of Xinjiang's cotton and textile and apparel industry chain has exceeded 220 billion yuan.With the nation's largest cotton production,a complete industrial chain system,and strong synergistic effects,Xinjiang has become a leading and highly competitive textile industry hub in China. 展开更多
关键词 clustering XINJIANG cotton production apparel industry chemical fiber industrial chain textile industry output value
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Analysis of Causes and Mesoscale Cloud Clusters of a Backflow Blizzard Process in Central Inner Mongolia
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作者 Yushu WU Xiaoli GUO 《Meteorological and Environmental Research》 2026年第1期16-20,28,共6页
Based on the conventional observation data,daily reanalysis data from NCAR/NCEP,and TBB data derived from FY-2G infrared cloud images in April 2018,a heavy snowfall weather process in central Inner Mongolia from April... Based on the conventional observation data,daily reanalysis data from NCAR/NCEP,and TBB data derived from FY-2G infrared cloud images in April 2018,a heavy snowfall weather process in central Inner Mongolia from April 4 to 6 in 2018 was analyzed.The results show that the low trough at 500 hPa,the southerly wind jet stream at 700 hPa,and the inverted trough on the ground were the main influencing systems causing this blizzard.The transportation of warm and humid air by the southerly wind jet stream at 700 hPa and intense water vapor convergence provided sufficient water vapor conditions for the blizzard,and the moist layer in the blizzard area was deep.The low-level MPV in the blizzard area was<0,and the atmosphere was in a conditional symmetric instability state.The coupling of the upper and lower-level jets induced strong ascending motion.With the invasion of cold air,a low-level cold pad was formed,so that the warm and humid air tilted upward.The secondary circulation updraft triggered by the wet Q vector system released the conditional symmetric instability energy,so that the sloping motion was more intense,and the heavy snowfall appeared.Meanwhile,there was a good correspondence relationship between the blizzard area and the large-value area of low-level wet Q vector divergence.The mesoscale cloud clusters continuously generating,merging,and moving eastward in Hetao area were the direct cause of this blizzard,and the TBB of the cloud clusters was≤-56℃.The blizzard happened in the the edge gradient and large-value area of TBB. 展开更多
关键词 BLIZZARD Cold pad Conditional symmetric instability Wet Q vector Mesoscale cloud cluster
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Chiral europium-organotin oxo-clusters with dual-emission circularly polarized luminescence
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作者 Gui-Xin Yan Er-Xia Chen +2 位作者 Jin-Xia Yang Jian Zhang Qipu Lin 《Chinese Journal of Structural Chemistry》 2025年第12期90-94,共5页
Chiral metal-organic clusters(MOCs)integrating lanthanide ions(Ln^(3+))and organic luminophores present a promising platform for modulating circularly polarized luminescence(CPL).However,achieving dual-wavelength CPL ... Chiral metal-organic clusters(MOCs)integrating lanthanide ions(Ln^(3+))and organic luminophores present a promising platform for modulating circularly polarized luminescence(CPL).However,achieving dual-wavelength CPL in discrete cluster systems constitutes a considerable challenge.Herein,two enantiomeric pairs of heterometallic EuSn oxo clusters,designated as Sn_(2)EuL_(2)-R/S and Sn_(2)EuL_(4)-R/S,were strategically synthesized using axially chiral binaphthol-phosphonate ligands.These hybrid clusters exhibit dual emission,characterized by a broad ligand-derived fluorescence band superimposed with sharp,characteristic Eu^(3+)f-f transitions,which enables excitation-dependent luminescence color tuning.Their emission profiles and quantum yields are found to be exquisitely adjusted by the distinct coordination environments of Sn^(4+)centers.Notably,Sn_(2)EuL_(2)-R/S demonstrates CPL activity in both near-UV(|g_(lum)|=1.7×10^(-3))and visible(|g_(lum)|=3.1×10^(-2))regions.This work not only reports the first instance of dual-wavelength CPL in a lanthanide/tin oxo complex but also establishes a robust design strategy for fabricating color-tunable chiral photonic materials. 展开更多
关键词 Heterometallic oxo clusters Organotin clusters Chirality Circularly polarized luminescence Dual emission
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Suzaku Observation of Merging Clusters A222 and A223
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作者 Yanling Chen Wei Cui +2 位作者 Aurora Simionescu Rui Huang Dan Hu 《Research in Astronomy and Astrophysics》 2025年第6期110-119,共10页
Previous X-ray and optical studies of the galaxy cluster pair A222/223 suggested the possible presence of a=lamentary structure connecting the two clusters,a result that appears to be supported by subsequent weak-lens... Previous X-ray and optical studies of the galaxy cluster pair A222/223 suggested the possible presence of a=lamentary structure connecting the two clusters,a result that appears to be supported by subsequent weak-lensing analyses.This=lament has been reported to host a primordial warm-hot intergalactic medium,which existed prior to being heated by the interactions of the clusters.In this study,we made an attempt to examine the reported emission feature with data from an archival Suzaku observation,taking advantage of its low detector background.Because the emission is expected to be very weak,we=rst carefully examined all potential sources of“contamination,”and then modeled the residual emission.Due to large uncertainties,unfortunately,our results can neither con=rm the presence of the reported emission feature nor rule it out.We discuss the sources of uncertainties. 展开更多
关键词 GALAXIES clusters intracluster medium-X-rays GALAXIES clusters-(cosmology:)large-scale structure of universe
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Exploring core symptoms and symptom clusters among patients with neuromyelitis optica spectrum disorder: A network analysis 被引量:2
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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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Analytical Approach to Clusters in near Critical CO2 被引量:1
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作者 Boris Sedunov Ilia Brondz 《International Journal of Analytical Mass Spectrometry and Chromatography》 2016年第3期39-50,共13页
Clusters greatly influence thermophysical properties of near critical gases. The cluster structures of supercritical fluids in general and Carbon Dioxide especially are important for the advanced supercritical fluid t... Clusters greatly influence thermophysical properties of near critical gases. The cluster structures of supercritical fluids in general and Carbon Dioxide especially are important for the advanced supercritical fluid technologies and analytics development. The paper extends to near critical densities the developed earlier methods to extract the clusters’ properties from Online Electronic Database of NIST on thermophysical properties of fluids. This Database contains a hidden knowledge of cluster fractions’ properties in real gases. The discovered earlier linear chain clusters dominate at intermediate densities. Their properties can be extrapolated to high density gases, thus opening the way to study large 3D clusters in near critical zone. The potential energy density of a gas, cleared from the chain clusters’ contribution, reflects only the 3D clusters’ characteristics. A series expansion of this value by the Monomer Fraction density discovers properties of n-particle 3D clusters. The paper demonstrates a discrete row of 3D clusters’ particle numbers and gives estimations for bond energies of these clusters. 展开更多
关键词 Real Gas Supercritical Fluid CLUSTER Bond Energy Equilibrium Constant Potential Energy Theoretical and Analytical Approach to clusters Energetic of clusters clusters in Extraction Process clusters in Analytical Chemistry
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Evaporation-Processed X-Ray Imaging Scintillation Screen Based on Copper Clusters
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作者 Xie Gaozhan Chen Cheng +9 位作者 Zhang Jingru Xiao Dongjie Cai Minyue Gao Qiya Gao Zhisheng Sun Chengxi Li Hui Li Huanhuan Chen Runfeng Tao Ye 《有机化学》 北大核心 2025年第11期4219-4226,共8页
Organic-inorganic hybrid clusters with strong X-ray radioluminescence have exhibited great potential in scintillator field.However,fabricating the X-ray imaging screens of the clusters without sacrificing the scintill... Organic-inorganic hybrid clusters with strong X-ray radioluminescence have exhibited great potential in scintillator field.However,fabricating the X-ray imaging screens of the clusters without sacrificing the scintillation performance is challenging.Herein,we report an effective way to prepare high-quality scintillation films of two synthesized Cu(Ⅰ)clusters through vacuum evaporation deposition.The developed Cu(Ⅰ)clusters with rigid molecular structures show excellent scintillation performance with a high light yield of up to 19356.7 photons/MeV and a low detection limit of 158 nGy/s.The scintillation film based on the Cu(Ⅰ)clusters made by vacuum evaporation deposition is highly uniform with a small surface roughness value of 1.04 nm,which can be applied to X-ray imaging for various objects.These results not only provide important guidance to develop high-performance organic-inorganic hybrid scintillators,but also pave a straightforward way to prepare non-doped scintillation screens for remarkable X-ray imaging applications. 展开更多
关键词 scintillator RADIOLUMINESCENCE Cu(Ⅰ)clusters vacuum evaporation deposition X-ray imaging
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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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Extracting fuzzy clusters from massive attributed graphs using Markov lumpability optimization
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作者 Kai-Yue Jiang Li-Heng Xu +3 位作者 Shi-Pei Lin Li-Yang Zhou Hui-Jia Li Ge Gao 《Chinese Physics B》 2025年第10期609-617,共9页
Attributed graph clustering plays a vital role in uncovering hidden network structures,but it presents significant challenges.In recent years,various models have been proposed to identify meaningful clusters by integr... Attributed graph clustering plays a vital role in uncovering hidden network structures,but it presents significant challenges.In recent years,various models have been proposed to identify meaningful clusters by integrating both structural and attribute-based information.However,these models often emphasize node proximities without adequately balancing the efficiency of clustering based on both structural and attribute data.Furthermore,they tend to neglect the critical fuzzy information inherent in attributed graph clusters.To address these issues,we introduce a new framework,Markov lumpability optimization,for efficient clustering of large-scale attributed graphs.Specifically,we define a lumped Markov chain on an attribute-augmented graph and introduce a new metric,Markov lumpability,to quantify the differences between the original and lumped Markov transition probability matrices.To minimize this measure,we propose a conjugate gradient projectionbased approach that ensures the partitioning closely aligns with the intrinsic structure of fuzzy clusters through conditional optimization.Extensive experiments on both synthetic and real-world datasets demonstrate the superior performance of the proposed framework compared to existing clustering algorithms.This framework has many potential applications,including dynamic community analysis of social networks,user profiling in recommendation systems,functional module identification in biological molecular networks,and financial risk control,offering a new paradigm for mining complex patterns in high-dimensional attributed graph data. 展开更多
关键词 attributed clustering Markov chain lumped random walk fuzzy clusters OPTIMIZATION
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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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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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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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Trajectory and Influencing Factors of Postoperative Vulnerable Symptom Clusters in Lung Transplant Recipients
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作者 Xue Li Ying Jin +1 位作者 Jing Hu Junrong Ding 《Journal of Clinical and Nursing Research》 2025年第11期172-183,共12页
The first three months after lung transplantation are the clinical“vulnerable period”.Complications during this period often appear in the form of symptom clusters.The core includes primary graft dysfunction(PGD),in... The first three months after lung transplantation are the clinical“vulnerable period”.Complications during this period often appear in the form of symptom clusters.The core includes primary graft dysfunction(PGD),infection,inflammatory response and multiple organ dysfunction,and are interconnected to form a complex network.The symptom cluster shows a clear dynamic trajectory:the risk of PGD peaks at 24 hours after surgery,and its evolution trajectory(recovery,delay,deterioration)directly affects long-term graft function;infections show a“double peak distribution”,with bacteria/fungi dominant in the early stage(<1 month)and viruses/opportunistic infections dominant in the middle stage(1-6 months),and promote each other with PGD.Influencing factors include four dimensions:donor(smoking history,infection),recipient(weakness,immune status),perioperative period(surgical method,support strategy)and postoperative management(balance of immunosuppression).In the future,dynamic prediction models and individualized management paths need to be built to improve patient outcomes. 展开更多
关键词 Lung transplantation Symptom clusters Postoperative complications TRAJECTORY
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