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single-atom“surgery”on chiral all-dialkynyl-protected superatomic silver nanoclusters

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Science Bulletin 2025年第3期70卷 365-372页

作者： Chengkai Zhang Wei-Dan si Wei-Dong Tian Wan-jun xiao Zhi-Yong Gao Zhi wang Chen-Ho Tung Di Sun School of Chemistry and Chemical Engineering State Key Laboratory of Crystal MaterialsShandong UniversityJinan 250100China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007China

The manipulation of single atom within the metallic kernel of nanoclusters has attracted considerable attention due to its potentials to elucidate kernel-based structure-property relationships at the single-atom ***,new-designed chiral bialkynyl ligands,have been chosen as protective agents to isolate two pairs of 8-electron superatomic silver nanoclusters,R/S-Ag39 and R/S-Ag40.X-ray diffraction analysis reveals that Ag39 and Ag40 with the same number of chiral ligands,possess a closely analogous silver skeleton but a single-atomic *** incorporation of an extra Ag40th atom into Ag40 evokes two significant changes of structure and property compared to Ag39:(i)a reduction in the symmetry of the entire nanocluster,resulting in an enhancement of kernel-related asymmetry g-factor;(ii)a regulation of the transitions(1P→1D and Ligand(π)→1D)of excited state,leading to a second near-infrared(NIR-II,1000-1700 nm)phosphorescent emission red-shift from 1088 to 1150 *** work not only provides vital insights into the relationship between structures and ground/excited states chiroptical activities at the single-atom level,but also presents bialkynyl as a promising stabilizing agent for building superatomic metal nanoclusters.

关键词： single atom manipulation Chiral bialkynyl ligands Superatomic silver nanoclusters NIR-Il phosphorescence

Least Square Estimation for Multiple Functional Linear Model with Autoregressive Errors

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Acta Mathematicae Applicatae sinica 2025年第1期41卷 84-98页

作者： Meng wang Ming-liang SHU Jian-jun ZHOU si-xin WU Min CHEN School of Management University of Science and Technology of ChinaHefei 230026China Academy of Mathematics and System Science Chinese Academy of SciencesBeijing 100190China Yunnan Key Laboratory of Statistical Modeling and Data Analysis Yunnan UniversityKunming 650091China

As an extension of linear regression in functional data analysis, functional linear regression has been studied by many researchers and applied in various fields. However, in many cases, data is collected sequentially over time, for example the financial series, so it is necessary to consider the autocorrelated structure of errors in functional regression background. To this end, this paper considers a multiple functional linear model with autoregressive errors. Based on the functional principal component analysis, we apply the least square procedure to estimate the functional coefficients and autoregression coefficients. Under some regular conditions, we establish the asymptotic properties of the proposed estimators. A simulation study is conducted to investigate the finite sample performance of our estimators. A real example on China's weather data is applied to illustrate the validity of our model.

关键词： multiple functional linear model autoregressive errors principal component analysis consistency

Genomic insights into ecological adaptation of oaks revealed byphylogenomic analysis of multiple species

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Plant Diversity 2025年第1期47卷 53-67页

作者： Tian-Rui wang Xin Ning si-si Zheng Yu Li Zi-Jia Lu Hong-Hu Meng bin-Jie Ge Gregor Kozlowski Meng-xiao Yan Yi-Gang Song Eastern China Conservation Centre for Wild Endangered Plant Resources Shanghai Chenshan Botanical GardenShanghai 201602China College of Forestry and Biotechnology Zhejiang A&F UniversityHangzhou 311300China College of Life Sciences Shanghai Normal UniversityShanghai 200234China Plant Phylogenetics and Conservation Group Centre for Integrative ConservationXishuangbanna Tropical Botanical GardenChinese Academy of SciencesKunming 650223China Department of Biology and Botanic Garden University of FribourgFribourgSwitzerland Natural History Museum Fribourg FribourgSwitzerland

Understanding the ecological adaptation of tree species can not only reveal the evolutionary potential but also benefit biodiversity conservation under global climate *** is a keystone genus in Northern Hemisphere forests,and its wide distribution in diverse ecosystems and long evolutionary history make it an ideal model for studying the genomic basis of ecological *** we used a newly sequenced genome of Quercus gilva,an evergreen oak species from East Asia,with 18 published Fagales genomes to determine how Fagaceae genomes have evolved,identify genomic footprints of ecological adaptability in oaks in general,as well as between evergreen and deciduous *** found that oak species exhibited a higher degree of genomic conservation and stability,as indicated by the absence of large-scale chromosomal structural variations or additional whole-genome duplication *** addition,we identified expansion and tandem repetitions within gene families that contribute to plant physical and chemical defense(e.g.,cuticle biosynthesis and oxidosqualene cyclase genes),which may represent the foundation for the ecological adaptation of oak *** rhythm and hormone-related genes may regulate the habits of evergreen and deciduous *** study provides a comprehensive perspective on the ecological adaptations of tree species based on phylogenetic,genome evolutionary,and functional genomic analyses.

关键词： Quercus Ecological adaptation Phylogenomics Transcriptomes Fagaceae

First observation results of Macao Science Satellite-1 on lightning-induced electron precipitation

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Science China Earth Sciences 2025年第1期68卷 1-10页

作者： Yongping wang Yixin SUN Qiugang ZONG Gaopeng LU Xudong GU Ze-jun HU bin LI Key Laboratory for Polar Science Ministry of Natural ResourcesPolar Research Institute of ChinaShanghai 200136China Institute of Space Physics and Applied Technology Peking UniversityBeijing 100871China State Key Laboratory of Lunar and Planetary Science Macao University of Science and TechnologyMacao 999078China School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China School of Electronic Information Wuhan UniversityWuhan 430072China

The Medium-energy Electron Spectrometers(MES)is a space-borne instrument onboard Macao Science Satellite-1(MSS-1)dedicated to monitoring the typical charged particle radiation characteristics in the satellite orbit and the process of their occurrence and development,including short bursts of lightning-induced electron precipitation(LEP).This paper presents the first results of the LEP measurements by the MSS-1.47 LEP events are identified with the routine operation for 3 months since satellite launch,all within the range of 1.5sist of 40–300 keV electrons.A preliminary observation result indicates that,with medium-energy electron detectors,MSS-1can present in-situ observations of large regions of enhanced background precipitation and reveal their fine spatiotemporal characteristics and spectral *** collaborative VLF ground-based measurements at the Great Wall Station,Antarctica also have a good correspondence with LEP measurements of *** observations also imply that lightning activity has a modulation effect on the energetic electron energy-spatial structure.

关键词： Lightning-induced electron precipitation Inner radiation belts Energetic electrons Macao Science Satellite-1

Thickness and sp3 bond modulation of（Ti/tetrahedral amorphous carbon）_n multilayer coatings

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Tungsten 2025年第1期7卷 152-160页

作者： Zhi-jun Xie Jia-Lin Li Ling Gong Xiang-Li Zhong Hong-Jia Song Jin-bin wang National-Provincial Laboratory of Special Function Thin Film Materials School of Materials Science and Engineering Xiangtan University

The durability of wear-resistant tetrahedral amorphous carbon（ta-C） coatings is intimately linked to their thickness and the concentration of *** enhance the lifespan of the coatings,we have prepared a multilayer coating consisting of alternating layers of Ti and ta-C,denoted as（Ti/ta-C）_n,using arc ion plating.A multi-layer structure in conjunction with stage cooling is employed to enhance the thickness and promote *** results indicate that the ID/IGvalue,representing the ratio of the intensity of the D peak to that of the G peak in Raman spectroscopy,decreases from 0.85 when no stage cooling is applied to 0.35 when stage cooling is employed,suggesting an enhancement in the fraction of sp3bonds within the *** obtained（Ti/ta-C）_n multilayer coating without peeling off has a maximum thickness of 1.14 μm,which is almost double that of the ta-C coating single layer *** the same time,the coating has a low coefficient of friction,down to 0.069,and maintains excellent friction properties with a wear rate of 3.4×10-6mm3·N-1·*** results conclusively show that the preparation technology can enhance both thickness and sp3bonding in ta-C coatings,significantly expanding their utility across tools,molds,and precision engineering components.

关键词： Arc ion plating Multilayer structure sp3 bond Ta-C coating Wear resistance

Prevalence,risk factors and clinical features of sensory A-V pattern exotropia

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International Journal of Ophthalmology(English edition) 2025年第2期18卷 323-329页

作者： bin-bin Zhu Shi-Yu Tang Xiang-jun wang Li-Cheng Fu Jian-Hua Yan State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-Sen UniversityGuangzhou 510060Guangdong ProvinceChina Ophthalmology Department of Surgerythe Second People’s Hospital of FoshanFoshan 528000Guangdong ProvinceChina

AIM:To investigate the potential mechanisms of A-V pattern and evaluate the surgical outcomes used in the treatment of sensory ***:The medical records of patients with sensory A-V pattern exotropia who underwent strabismus surgery between May 2014 to june 2019 was retrospectively *** control group included sensory exotropia patients without A-V pattern and concomitant A-V pattern exotropia patients with normal vision who undergone strabismus surgery over this same time *** alignment,best corrected visual acuity,oblique muscle function,and stereopsis records were ***:Among the 843 eligible patients,91(10.79%;39 males and 52 females)had A-pattern(54,6.4%)or V-pattern(37,4.4%).Age at onset of vision impairment was 4±5y and at the time of surgery was 25±*** significant negative correlations were present between impaired visual acuity and the pre-operative exodeviation(r=-0.198,P=0.016)and patterns(r=-0.207,P=0.015).Age at surgery and exodeviation in patients with concomitant A-V pattern exotropia was significantly earlier as compared with that of sensory A-V pattern exotropia and sensory exotropia(both Psignificant differences in these clinical variables between sensory exotropia with or without A-V *** and pattern were significantly reduced in patients receiving horizontal rectus surgery with or without oblique muscle surgery(both PsiON:The prevalence of sensory A-V pattern exotropia in our study is 10.79%.Visual acuity represents an important factor contributing to the occurrence and development of A-V *** horizontal rectus surgery can provide a good option for the correction of sensory A-V pattern exotropia.

关键词： sensory exotropia A-V pattern oblique muscle dysfunction horizontal rectus surgery

Steady-state and transient investigation of a small pressurized water reactor ACPR50S for different ATFs based on Bamboo-C code

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Nuclear Science and Techniques 2025年第1期36卷 192-206页

作者： Kun Zhuang Ying-Zhen wang Li-Na Deng Yong-Zhan wang Wen Shang si-Peng wang Department of Nuclear Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China

Small modular reactors have received widespread attention owing to their inherent safety,low investment,and *** pressurized water reactors(SPWRs)have become important candidates for SMRs owing to their high technological *** the Fukushima accident,research on accident-tolerant fuels(ATFs),which are more resistant to serious accidents than conventional fuels,has gradually *** study analyzes the neutronics and thermal hydraulics of an SPWR(ACPR50S)for different ATFs,BeO+UO_(2)−siC,BeO+UO_(2)−FeCrAl,U_(3)si_(2)−siC,and U_(3)si_(2)−FeCrAl,based on a PWR fuel management code,the Bamboo-C deterministic *** the steady state,the burnup calculations,reactivity coefficients,power and temperature distributions,and control rod reactivity worth were *** transients of the control rod ejection accident for the two control rods with the maximum and minimum reactivity worth were *** results showed that 5%B-10 enrichment in the wet annular burnable absorbers assembly can effectively reduce the initial reactivity and end-of-life reactivity *** BeO+UO2−siC core exhibited superior neutronic characteristics in terms of burnup and negative temperature reactivity compared with the other three cases owing to the strong moderation ability of BeO+UO_(2)and low neutron absorption of ***,the U_(3)si_(2)core had a marginally better power-flattening effect than BeO+UO_(2),and the differential worth of each control rod group was similar between different *** the transient of a control rod ejection,the changes in the fuel temperature,coolant temperature,and coolant density were *** maximum difference was less than 10℃ for the fuel temperature and 2℃ for the coolant temperature.

关键词： ACPR50S Small pressurized water reactor ATF Steady Transient

Hemispheric asymmetries and network dysfunctions in adolescent depression:A neuroimaging study using resting-state functional magnetic resonance imaging

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World Journal of Psychiatry 2025年第2期15卷 100-108页

作者： Ying Xiong Ren-Qiang Yu Xing-Yu wang Shun-si Liang Jie Ran xiao Li Yi-Zhi Xu Department of Hematology Chongqing General HospitalChongqing UniversityChongqing 401147China Department of Radiology The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Psychiatry The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China

BACKGROUND Currently,adolescent depression is one of the most significant public health concerns,markedly influencing emotional,cognitive,and social *** advancements in distinguish the neurobiological substrates underlying depression,the intricate patterns of disrupted brain network connectivity in adolescents warrant further *** To elucidate the neural correlates of adolescent depression by examining brain network connectivity using resting-state functional magnetic resonance imaging(rs-fMRI).METHODS The study cohort comprised 74 depressed adolescents and 59 healthy controls aged 12 to 17 *** underwent rs-fMRI to evaluate functional connectivity within and across critical brain networks,including the visual,default mode network(DMN),dorsal attention,salience,somatomotor,and frontoparietal control *** Analyses revealed pronounced functional disparities within key neural circuits among adolescents with *** results demonstrated existence of hemispheric asymmetries characterized by enhanced activity in the left visual network,which contrasted the diminished activity in the right *** DMN facilitated increased activity within the left prefrontal cortex and reduced engagement in the right hemisphere,implicating disrupted self-referential and emotional processing ***,an overactive right dorsal attention network and a hypoactive salience network were identified,underscoring significant abnormalities in attentional and emotional regulation in adolescent *** The findings from this study underscore distinct neural connectivity disruptions in adolescent depression,underscoring the critical role of specific neurobiological markers for precise early diagnosis of adolescent *** observed functional asymmetries and network-specific deviations elucidate the complex neurobiological architecture of adolescent depression,supporting the development of targeted the

关键词： Adolescent depression Brain network connectivity Neuroimaging biomarkers Functional magnetic resonance imaging Default mode network Salience network Hemispheric asymmetry

Efficient chemical mechanical polishing of W promoted by Fenton-like reaction between Cu^(2+)and H_(2)O_(2)

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Transactions of Nonferrous Metals Society of China 2025年第1期35卷 257-270页

作者： Hong-yu CHEN Lin wang Feng PENG Meng-meng SHEN Wei HANG Tufa Habtamu BERI Hui-bin ZHANG jun ZHAO Yun-xiao HAN bing-hai LÜ College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310023China Key Laboratory of Special Purpose Equipment and Advanced Processing Technology Ministry of EducationZhejiang University of TechnologyHangzhou 310023China Adama Science and Technology University Adama 1888Ethiopia College of Materials Science and Engineering Zhejiang University of TechnologyHangzhou 310014China

The Fenton-like reaction between Cu^(2+)and H_(2)O_(2)was employed in chemical mechanical polishing to achieve efficient and high-quality processing of *** microstructure evolution and material removal rate of tungsten during polishing process were investigated via scanning electron microscopy,X-ray photoelectron spectroscopy,ultraviolet−visible spectrophotometry,and electrochemical *** passivation behavior and material removal mechanism were *** show that the use of mixed H_(2)O_(2)+Cu(NO_(3))_(2)oxidant can achieve higher polishing efficiency and surface quality compared with the single oxidant Cu(NO_(3))_(2)or H_(2)O_(2).The increase in material removal rate is attributed to the rapid oxidation of W into WO_(3)via the chemical reaction between the substrate and hydroxyl radicals produced by the Fenton-like *** addition,material removal rate and static etch rate exhibit significantly different dependencies on the concentration of Cu(NO_(3))_(2),while the superior oxidant for achieving the balance between polishing efficiency and surface quality is 0.5 wt.%H_(2)O_(2)+1.0 wt.%Cu(NO_(3))_(2).

关键词： chemical mechanical polishing tungsten Fenton-like reaction hydroxyl radical material removal mechanism