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Large scale synthesis of full-color emissive carbon dots from a single carbon source by a solvent-free method

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Nano Research 2022年第4期15卷 3548-3555页

作者： Hui Ding Xuan-Xuan Zhou Zi-Hui Zhang yun-peng zhao Ji-Shi Wei Huan-Ming Xiong Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education and College of Chemical Engineering China University of Mining and TechnologyXuzhou 221116China Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Fudan UniversityShanghai 200433China

Full-color emissive carbon dots(CDs)hold a great promise for various applications,especially in light emitting diodes(LEDs).However,the existing synthetic routes for CDs are carried out in solutions,which suffer from low yields,high pressures,various byproducts,large amounts of waste solvents,and complicated photoluminescence(PL)***,it is necessary to explore large scale synthesis of CDs with high quantum yield(QY)across the entire visible range from a single carbon source by a solvent-free *** this work,a series of CDs with tunable PL emission from 442 to 621 nm,QY of 23%-56%,and production yield within 34%-72%,are obtained by heating o-phenylenediamine with the catalysis of *** characterizations identify that,the differences between these CDs with respect to the graphitization degree,graphitic nitrogen content,and oxygen-containing functional groups,are responsible for their distinct optical properties,which can be modulated by controlling the deamination and dehydrogenation processes during ***,green,yellow,red emissive films,and LEDs are prepared by dispersing the corresponding CDs into polyvinyl alcohol(PVA).All types of white LEDs(WLEDs)with high colorrendering-index(CRI),including warm WLEDs,standard WLEDs,and cool WLEDs,are also fabricated by mixing the red,green,and blue emissive CDs into PVA matrix by the appropriate ratios.

关键词： carbon dots solvent-free synthesis full-color luminescence surface state white light emitting diodes

Benchmarking gene set of gymnosperms for assessing genome and annotation completeness in BUSCO

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Horticulture Research 2023年第9期10卷 278-280页

作者： Jun-Jie Wu Yu-Wei Han Chen-Feng Lin Jing Cai yun-peng zhao Systematic&Evolutionary Botany and Biodiversity Group MOE Key Laboratory of Biosystem Homeostasis and ProtectionCollege of Life SciencesZhejiang UniversityHangzhou 310058China School of Ecology and Environment Northwestern Polytechnical UniversityXi’an 710129China

Dear Editor,Gymnosperms,naked-seed plants,are phylogenetically sister to the flowering plants(angiosperms),of which the origin can be traced back to the Devonian *** their f lourishing diversity in the Mesozoic era,only∼1000 living species of gymnosperms exist in the modern flora(∼0.4%of the number of angiosperms)[1].However,they account for at least 39%of the world’s forests[2]and hold great economic and cultural importance in horticulture,medicine,and the timber industry[3].

关键词： period. culture spite

Remote sensing of subtropical tree diversity:The underappreciated roles of the practical definition of forest canopy and phenological variation

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Forest Ecosystems 2023年第3期10卷 378-386页

作者： Yongchao Liu Ruyun Zhang Chen-Feng Lin zhaochen Zhang Ran Zhang Kankan Shang Mingshui zhao Jingyue Huang Xiaoning Wang You Li Yulin Zeng yun-peng zhao Jian Zhang Dingliang Xing Zhoushan Archipelago Observation and Research Station Institute of Eco-Chongming(IEC)Zhejiang Tiantong Forest Ecosystem National Observation Research StationSchool of Ecological and Environmental SciencesEast China Normal UniversityShanghai200241China Systematic&Evolutionary Botany and Biodiversity Group MOE Key Laboratory of Biosystems Homeostasis&ProtectionCollege of Life SciencesZhejiang UniversityHangzhou310058China Shanghai Chenshan Botanical Garden Shanghai201602China Tianmushan National Nature Reserve Management Bureau Hangzhou311311China

Tree species diversity is vital for maintaining ecosystem functions,yet our ability to map the distribution of tree diversity is limited due to difficulties in traditional field-based *** developments in spaceborne remote sensing provide unprecedented opportunities to map and monitor tree diversity more *** we built partial least squares regression models using the multispectral surface reflectance acquired by Sentinel-2 satellites and the inventory data from 74 subtropical forest plots to predict canopy tree diversity in a national natural reserve in eastern *** particular,we evaluated the underappreciated roles of the practical definition of forest canopy and phenological variation in predicting tree diversity by testing three different definitions of canopy trees and comparing models built using satellite imagery of different *** best models explained 42%–63%variations in observed diversities in cross-validation tests,with higher explanation power for diversity indices that are more sensitive to abundant *** models built using imageries from early spring and late autumn showed consistently better fits than those built using data from other seasons,highlighting the significant role of transitional phenology in remotely sensing plant *** results suggested that the cumulative diameter(60%–80%)of the biggest trees is a better way to define the canopy layer than using the subjective fixeddiameter-threshold(5–12 cm)or the cumulative basal area(90%–95%)of the biggest ***,these approaches resulted in contrasting diversity maps that call attention to canopy structure in remote sensing of tree *** study demonstrates the potential of mapping and monitoring tree diversity using the Sentinal-2 data in species-rich forests.

关键词： Canopy structure Multispectral remote sensing Seasonal phenology Subtropical forest Tree species diversity

Phylogenetic diversity of eastern Asia-eastern North America disjunct plants is mainly associated with divergence time

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Plant Diversity 2023年第1期45卷 27-35页

作者： Han-Yang Lin Miao Sun Ya-Jun Hao Daijiang Li Matthew A.Gitzendanner Cheng-Xin Fu Douglas E.Soltis Pamela S.Soltis yun-peng zhao Laboratory of Systematic and Evolutionary Botany and Biodiversity College of Life SciencesZhejiang UniversityHangzhou 310058China Key Laboratory of Horticultural Plant Biology(Ministry of Education) Huazhong Agricultural UniversityWuhan 430070China Florida Museum of Natural History University of FloridaGainesvilleFL 32611USA Department of Biology University of FloridaGainesvilleFL 32611USA Biodiversity Institute University of FloridaGainesvilleFL 32611USA Genetics Institute University of FloridaGainesvilleFL 32608USA School of Advanced Study Taizhou UniversityTaizhou 318000China

The underlying causes of biodiversity disparities among geographic regions have long been a fundamental theme in ecology and ***,the patterns of phylogenetic diversity(PD) and phylogenetic beta diversity(PBD) of congeners that are disjunctly distributed between eastern Asia-eastern North America(EA-ENA disjuncts) and their associated factors remain *** we investigated the standardized effect size of PD(SES-PD),PBD,and potentially associated factors in 11natural mixed forest sites(five in EA and six in ENA) where abundant EA-ENA disjuncts *** found that the disjuncts in ENA possessed higher SES-PD than those in EA at the continental scale(1.96vs-1.12),even though the number of disjunct species in ENA is much lower than in EA(128 vs 263).SESPD of the EA-ENA disjuncts tended to decrease with increasing latitude in 11 *** latitudinal diversity gradient of SES-PD was stronger in EA sites than in ENA *** on the unweighted unique fraction metric(UniFrac) distance and the phylogenetic community dissimilarity,PBD showed that the two northern sites in EA were more similar to the six-site ENA group than to the remaining southern EA *** on the standardized effect size of mean pairwise distances(SES-MPD),nine of eleven studied sites showed a neutral community structure(-1.96 ≤SES-MPD ≤1.96).Both Pearson’s r and structural equation modeling suggested that SES-PD of the EA-ENA disjuncts was mostly associated with mean divergence ***,SES-PD of the EA-ENA disjuncts was positively correlated with temperaturerelated climatic factors,although negatively correlated with mean diversification rate and community *** applying approaches from phylogenetics and community ecology,our work sheds light on historical patterns of the EA-ENA disjunction and paves the way for further research.

关键词： EA-ENA disjuncts Climatic factors Community assembly processes Diversification rate Divergence time Phylogenetic diversity

Rapid and scalable preparation of highly quaternized polymer networks to achieve efficient simultaneous adsorption of iodide and pertechnetate

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Science China Chemistry 2025年第1期68卷 337-349页

作者： Meiyun Xu Song Gu Fulong Chen Zhe zhao peng Liu Daoben Hua State Key Laboratory of Radiation Medicine and Protection School of Radiological and Interdisciplinary Sciences (RAD-X) Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions Soochow University

The efficient separation of fission products,such as TcO4-and I-,holds strategic significance for the management of radioactive wastes and environmental *** this study,we propose an ultrafast strategy for scalable preparation of a highly quaternized organic network to facilitate efficient and synchronous separation of iodide and *** network can be prepared within a few minutes at room temperature,using polyethylenimine and 1,2,4,5-tetrakis（bromomethyl）benzene as building *** chlorine replacement,the network,abundantly decorated with quaternary ammonium groups （Cl@QPN）,exhibits an ultrahigh positive charge density of 7.6 mmol/*** enables the rapid and efficient enrichment of target anions through strong electrostatic Coulomb *** a result,Cl@QPN exhibits significantly higher adsorption rate constants of 0.830 g/（mg min） for ReO4-（a nonradioactive surrogate of TcO4-） and 0.677 g/（mg min） for I-compared to other ***,it possesses high adsorption capacities,reaching 1,681 mg/g for ReO4-and 917.4 mg/g for I-.Cl@QPN also demonstrates good selectivity towards target ions and shows efficient adsorption for99TcO4-.Additionally,Cl@QPN exhibits high dynamic processing capacities,handling up to 3,100 and 7,400 kg of simulated streams per kilogram of material for I-and ReO4-,respectively.

关键词： quaternized polymer networks adsorption pertechnetate iodide liquid radioactive streams

Plant and fungal species interactions differ between aboveground and belowground habitats in mountain forests of eastern China

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Science China(Life Sciences) 2023年第5期66卷 1134-1150页

作者： Teng Yang Leho Tedersoo Pamela S.Soltis Douglas E.Soltis Miao Sun Yuying Ma Yingying Ni Xu Liu Xiao Fu Yu Shi Han-Yang Lin yun-peng zhao Chengxin Fu Chuan-Chao Dai Jack A.Gilbert Haiyan Chu State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China Mycology and Microbiology Center University of TartuTartu 50409Estonia College of Science King Saud UniversityRiyadh 11451Saudi Arabia Florida Museum of Natural History University of FloridaGainesville 32611USA College of Horticulture and Forestry Sciences Huazhong Agricultural UniversityWuhan 430070China State Key Laboratory of Crop Stress Adaptation and Improvement School of Life SciencesHenan UniversityKaifeng 475004China Systematic&Evolutionary Botany and Biodiversity Group MOE Key Laboratory of Biosystems Homeostasis&ProtectionCollege of Life SciencesZhejiang UniversityHangzhou 310058China Jiangsu Key Laboratory for Microbes and Functional Genomics College of Life SciencesNanjing Normal UniversityNanjing 210003China Department of Pediatrics School of MedicineUniversity of CaliforniaSan DiegoLa Jolla 92093USA

Plant and fungal species interactions drive many essential ecosystem properties and processes;however,how these interactions differ between aboveground and belowground habitats remains unclear at large spatial ***,we surveyed 494 pairwise fungal communities in leaves and soils by Illumina sequencing,which were associated with 55 woody plant species across more than 2,000-km span of mountain forests in eastern *** relative contributions of plant,climate,soil and space to the variation of fungal communities were assessed,and the plant-fungus network topologies were *** phylogeny was the strongest predictor for fungal community composition in leaves,accounting for 19.1%of the *** soils,plant phylogeny,climatic factors and soil properties explained 9.2%,9.0%and 8.7%of the variation in soil fungal community,*** plant-fungus networks in leaves exhibited significantly higher specialization,modularity and robustness(resistance to node loss),but less complicated topology(e.g.,significantly lower linkage density and mean number of links)than those in *** addition,host/fungus preference combinations and key species,such as hubs and connectors,in bipartite networks differed strikingly between aboveground and belowground *** findings provide novel insights into cross-kingdom(plant-fungus)species co-occurrence at large spatial *** data further suggest that community shifts of trees due to climate change or human activities will impair aboveground and belowground forest fungal diversity in different ways.

关键词： bipartite network analyses foliar endophytic fungi modularity mountain forests plant phylogeny effect soil fungi specialization stability

Performance Analysis of a Coupled System based on Organic Rankine Cycle and Double Effect Absorption Refrigeration for Waste Heat Recovery in Data Center

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Journal of Thermal Science 2025年第1期34卷 188-205页

作者： LI peng XU Jiaqi WANG Binbin LIU Jianyang zhao Wensheng HAN Zhonghe School of Energy Power and Mechanical Engineering North China Electric Power University Hebei Key Laboratory of Low Carbon and High Efficiency Power Generation Technology North China Electric Power University

During data center operation,it generates a significant volume of low-grade waste *** recover waste heat,a coupled system including solar collector,double effect absorption refrigeration and organic Rankine cycle is *** system performance is analyzed in *** the organic Rankine cycle,five organic working fluids(R245fa,R245ca,R123,R11,and R113) are selected.R245fa,R113 and R245ca obtain the maximum net power output,thermal efficiency and exergy efficiency,*** the double effect absorption refrigeration system,the evaporation temperature,condensation temperature,and generation pressure affect the COP and exergy *** the generator pressure is unchanged,the COP increases with increasing evaporation temperature and decreasing condensation *** the COP reaches 1.3,the COP slightly decreases as the evaporation temperature or condensation temperature ***,the exergy efficiency of refrigeration systems exhibits the same trend as the COP,and the exergy efficiency maximum value appears at approximately 0.32.A new performance indicator,rPUE,was defined to evaluate the data center power utilization *** flow distribution ratio and heat source temperature were optimized with multi-objective *** the mass flow distribution rate is 0.6 and the heat source temperature is 441.5 K,rPUE and the total unit production costs of the system obtain the optimal solution.

关键词： Exergy

Channel pruning on frequency response

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Science China(Information Sciences) 2025年第1期68卷 159-170页

作者： Hang LIN Yifan peng Lin BIE Chenggang YAN Xibin zhao Yue GAO School of Software Tsinghua University School of Automation Hangzhou Dianzi University

Network pruning has a significant role in reducing network parameters and accelerating the inference time of the network. Some existing methods prune the network based on the frequency of the data, and finally obtain a sub-network with high accuracy. However, according to our experimental analysis, different frequencies of information in the data contribute differently to the accuracy of the model, and using this information directly for pruning without making a selection will lead to incorrect results. We believe that pruning should retain the convolutional kernels in the network that process important information, while those kernels that process unimportant information should be removed. In this paper, we first investigate the meaning of each frequency band information in the spectrum and their contribution to the prediction accuracy of the network,and according to these results, we propose a new pruning method based on frequency response(PFR). Our PFR finds and removes the convolutional kernels in the network that specialize in processing unimportant information, resulting in a compact neural network model. PFR obtains significant experimental results on different datasets, for example, a 56.0% raduction of float points operations(FLOPs) on Res Net-50 and only 0.37% of Top-1 accuracy degradation on the Image Net dataset.

关键词： deep learning model compression filter pruning channel pruning frequency response

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CaH2-promoted activity of Ni-carbonate interface for CO2 methanation

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Journal of Energy Chemistry 2025年第1期100卷 522-532页

作者： Jin-peng Wang Guo-Cui Mao Hui-Lin Jiang Bao-Xia Dong yun-Lei Teng School of Chemistry and Chemical Engineering Yangzhou University

Transition metal-carbonate interfaces often act as active sites in heterogeneous catalytic *** interface between transition metal and metal carbonate exhibits a dynamic equilibrium during the CO2hydrogenation reaction,involving surface carbonate hydrogenation and ***,there have been few reports on engineering the activity of the interface between transition metal and alkaline earth metal carbonate for catalytic *** work demonstrated that the incorporation of CaH2in Ni/CaCO3enhances the CO2methanation activity of the *** CO2conversion for Ni/CaH2-CaCO3reached 68.5%at 400°C,which was much higher than that of the Ni/CaCO3（31.6%） and Ni/CaH2-CaO （42.4%） ***,the Ni/CaH2-CaCO3catalysts remained stable during the stability test for 24 h at 400°C and 8 *** research revealed that CaH2played a crucial role in promoting the activity of the Ni-carbonate interface for ***2could modify the electronic structure of Ni and tune the structural properties of CaCO3to generate medium basic sites （OH groups）,which are favorable for the activation of H2and ***-situ Fourier transform infrared spectroscopy （FTIR） analysis combined with density functional theory calculations demonstrated that CO2activation occurs at the hydroxyl group （OH） on the CaH2-modified Ni-carbonate surface,leading to the formation of CO3H****,our study has confirmed that CO2methanation over the Ni/CaH2-CaCO3catalysts proceeds via the formate pathway.

关键词： CO 2 methanation Metal hydride Ni catalysts Carbonate Metal-carbonate interface