检索结果-南通市图书馆

Impact of Beijing’s“Coal to Electricity”program on ambient PM_(2.5) and the associated reactive oxygen species(ROS)

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2023年第11期133卷 93-106页

作者： Kaining Zhao yuanxun zhang Jing Shang james JSchauer Wei Huang Jingyu Tian Shujian yang Dongqing Fang Dong zhang College of Resources and Environment University of Chinese Academy of SciencesBeijing 101408China Beijing yanshan Earth Critical Zone National Research Station University of Chinese Academy of SciencesBeijing 101408China CAS Center for Excellence in Regional Atmospheric Environment Chinese Academy of SciencesXiamen 361021China Institute of Eco-Environmental Forensics Shandong UniversityQingdao 266237China Institute of Urban Meteorology China Meteorological AdministrationBeijing 100089China Wisconsin State Laboratory of Hygiene University of Wisconsin-MadisonMadisonWI53718USA Institute of Environmental Reference Materials of Environmental Development Center of Ministry of Ecology and Environment Beijing 100029China Meteorological Observation Center of China Meteorological Administration Beijing 100081China

The Beijing“Coal to Electricity”program provides a unique opportunity to explore air quality impacts by replacing residential coal burning with electrical *** this study,the atmospheric ROS(Gas-phase ROS and Particle-phase ROS,abbreviated to G-ROS and P-ROS)were measured by an online instrument in parallel with concurrent PM_(2.5) sample collections analyzed for chemical composition and cellular ROS in a baseline year(Coal Use year-CUy)and the first year following implementation of the“Coal to Electricity”program(Coal Ban year-CBy).The results showed PM_(2.5) concentrations had no significant difference between the two sampling periods,but the activities of G-ROS,P-ROS,and cellular ROS in CBy were 8.72 nmol H_(2)O_(2)/m^(3),9.82 nmol H 2 O 2/m 3,and 2045.75μg UD/mg PM higher than in *** sources were identified by factor-analysis from the chemical components of PM_(2.5).Secondary sources(SECs)were the dominant source of PM_(2.5) in the two periods,with 15.90%higher contribution in CBy than in *** Emission&Coal Combustion sources(Ind.&CCs),mainly from regional transport,also increased significantly in *** contributions of Aged Sea Salt&Residential Burning sources to PM_(2.5) decreased 5.31% from CUy to *** correlation results illustrated that Ind.&CCs had significant positive correlations with atmospheric ROS,and SECs significantly associated with cellular ROS,especially nitrates(r=0.626,p=0.000).Therefore,the implementation of the“Coal to Electricity”program reduced PM_(2.5) contributions from coal and biomass combustion,but had little effect on the improvement of atmospheric and cellular ROS.

关键词： PM_(2.5) Reactive oxygen species(ROS) Factor analysis(FA) Correlation Principal component regression(PCR)

Quaternion Quasi-Chebyshev Non-local Means for Color Image Denoising

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Electronics 2023年第3期32卷 397-414页

作者： XU Xudong zhang Zhihua M.james C.Crabbe School of Mathematics Shandong University Wolfson College University of Oxford

Quaternion non-local means(QNLM) denoising algorithm makes full use of high degree self-similarities inside images to suppress the noise, so the similarity metric plays a key role in its denoising *** this study, two improvements have been made for the QNLM: 1) For low level noise, the use of quaternion quasi-Chebyshev distance is proposed to measure the similarity of image patches and it has been used to replace the Euclidean distance in the QNLM algorithm. Since the quasi-Chebyshev distance measures the maximal distance in all color channels, the similarity of color images measured by quasi-Chebyshev distance can capture the structural similarity uniformly for each color channel; 2) For high level noise, quaternion bilateral filtering has been proposed as the preprocessing step in the QNLM algorithm. Denoising simulations were performed on 110 images of landscape, people, and architecture at different noise levels. Compared with QNLM, quaternion non-local total variation(QNLTV), and non-local means(NLM)variants(NLTV, NLM after wavelet threshold preprocessing, and the color adaptation of NLM), our novel algorithm not only improved PSNR/SSIM(peak signal to noise rate/structural similarity) and figure of merit values by an average of 2.77 dB/8.96% and 0.0491 respectively, but also reduced processing time.

关键词： Image color analysis Filtering Quaternions Noise reduction Color Euclidean distance Filtering algorithms

Physics-informed deep-learning parameterization of ocean vertical mixing improves climate simulations

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

National Science Review 2022年第8期9卷 167-174页

作者： yuchao Zhu Rong-Hua zhang james N.Moum Fan Wang Xiaofeng Li Delei Li CAS Key Laboratory of Ocean Circulation and Waves Institute of Oceanology and Center for Ocean Mega-Science Chinese Academy of Sciences Pilot National Laboratory for Marine Science and Technology (Qingdao) University of Chinese Academy of Sciences Center for Excellence in Quaternary Science and Global Change Chinese Academy of Sciences College of Earth Ocean and Atmospheric Sciences Oregon State University

Uncertainties in ocean-mixing parameterizations are primary sources for ocean and climate modeling biases. Due to lack of process understanding, traditional physics-driven parameterizations perform unsatisfactorily in the tropics. Recent advances in the deep-learning method and the new availability of long-term turbulence measurements provide an opportunity to explore data-driven approaches to parameterizing oceanic vertical-mixing processes. Here, we describe a novel parameterization based on an artificial neural network trained using a decadal-long time record of hydrographic and turbulence observations in the tropical Pacific. This data-driven parameterization achieves higher accuracy than current parameterizations, demonstrating good generalization ability under physical constraints. When integrated into an ocean model, our parameterization facilitates improved simulations in both ocean-only and coupled modeling. As a novel application of machine learning to the geophysical fluid, these results show the feasibility of using limited observations and well-understood physical constraints to construct a physics-informed deep-learning parameterization for improved climate simulations.

关键词： physics-informed deep learning climate model biases ocean vertical-mixing parameterizations long-term turbulence data artificial neural networks under physics constraint

Black holes as the source of dark energy:A stringent test with high-redshift JWST AGNs

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 181-188页

作者： Lei Lei Lei Zu Guan-Wen yuan Zhao-Qiang Shen yi-ying Wang yuan-Zhu Wang Zhen-Bo Su Wen-Ke Ren Shao-Peng Tang Hao Zhou Chi zhang Zhi-Ping Jin Lei Feng yi-Zhong Fan Da-Ming Wei Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China

Studies have proposed that there is evidence for cosmological coupling of black holes(BHs)with an index of k≈3;hence,BHs serve as the astrophysical source of dark ***,the data sample is limited for the redshifts of≤*** recent years,the james Webb Space Telescope(JWST)has detected many high-redshift active galactic nuclei(AGNs)and *** the JWST NIRSpec-/NIRCam-resolved AGNs,three are determined to be in early-type host galaxies with a redshift of z~***,their M_(*)and MBH are in tension with the predicted cosmological coupling of black holes with k=3 at a confidence level of~2σ,which challenges the hypothesis that BHs serve as the origin of dark *** work on high-redshift AGNs using the JWST will further assess such a hypothesis by identifying more early-type host galaxies in the higher mass range.

关键词： dark energy supermassive black hole active galactic nuclei james Webb Space Telescope

Geochronology,Mineralogy,and Geochemistry of the Tonsteins from the Permo–Carboniferous Benxi Formation,Ordos Basin,North China Craton

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2023年第5期97卷 1355-1371页

作者： WANG Luojing LÜDawei zhang Zhihui james C.HOWER Munira RAJI zhang yushuai SHEN yangyang GAO Jie Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals College of Earth Sciences and EngineeringShandong University of Science and TechnologyQingdaoShandong 266590China University of Kentucky Center for Applied Energy ResearchLexingtonKY 40511USA Sustainable Earth Institute University of PlymouthDevon PL48AAUK

Tonstein layers are found worldwide in the Permo-Carboniferous coal-bearing *** study investigates the geochronology,mineralogy,and geochemistry of four tonstein samples from the Permo-Carboniferous Benxi Formation,Ordos Basin,North China Craton(NCC).The typical features of the studied tonsteins include thin beds,lateral continuity,angular quartz grains,and euhedral zircons with similar U-Pb ages,indicating a significant pyroclastic *** addition,the tonstein samples have low TiO_(2)/Al_(2)O_(3)ratios(yttrium(REy)concentrations with obvious negative Eu anomalies,indicating that the tonsteins have a felsic magma ***,compared with the mean composition of clay shale,the studied tonsteins are characterized by high concentrations of the elements Nb and Ta,which may affect the concentration of the corresponding elements in surrounding coal *** zircon U-Pb ages of the tonsteins(293.9-298.8 Ma)provide a precise chronological framework on the Benxi Formation in the Ordos Basin,constraining the Gzhelian-Aselian *** tonsteins were probably sourced from arc volcanism along the western margin of the NCC during the early Permian,implying that the Alxa Terrane had not amalgamated with the NCC at that time.

关键词： tonsteins geochemistry Permo–Carboniferous North China Craton

A generalized synthesis method for freestanding multiferroic twodimensional layered supercell oxide films via a sacrificial buffer layer

在线全文

学校读者我要写书评

暂无评论

Nano Research 2023年第7期16卷 10559-10566页

作者： Jianan Shen Benson Kunhung Tsai Ke Xu Anyu Shang james PBarnard yizhi zhang Rahul Tripathi Zhihong Chen Xinghang zhang Haiyan Wang School of Materials Engineering Purdue UniversityWest LafayetteIndiana 47907USA Elmore Family School of Electrical and Computer Engineering Purdue UniversityWest LafayetteIndiana 47907USA Birck Nanotechnology Center Purdue UniversityWest LafayetteIndiana 47907USA

Multiferroics are an intriguing family of materials due to the simultaneous presence of two ferroic orderings,namely,ferroelectricity and *** are scientifically and technologically important and have numerous potential applications,such as four-state logic memories and multiferroic tunneling ***,the growth of epitaxial singlephase multiferroic thin films typically requires single crystalline oxide substrates,which hinders their future integration with Sibased *** this study,we report a generalized synthesis method that uses the polydimethylsiloxane(PDMS)-assisted wetetching method with an Sr_(3)Al_(2)O_(6)(SAO)sacrificial layer to transfer freestanding single-phase multiferroic Bi_(2)NiMnO_(6)(BNMO)films from conventional SrTiO_(3)(STO)substrates onto a Si *** structures and properties of the films have been characterized before and after the *** transferred films possess good multiferroic properties on Si wafers,indicating full compatibility with modern Si *** method can be generally applicable to other Bi-based multiferroic materials as ***,the original STO substrates after the transfer process have been recycled for preparing new batches of freestanding BNMO films,indicating a low-cost and sustainable method for manufacturing large-volume freestanding complex oxide thin films.

关键词： multiferroics freestanding films wet-transfer SAO sacrificial layer recyclable substrates sustainable

Forget less,count better:a domain-incremental self-distillation learning benchmark for lifelong crowd counting

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Information Technology & Electronic Engineering 2023年第2期24卷 187-202页

作者： Jiaqi GAO Jingqi LI Hongming SHAN yanyun QU james ZWANG Fei-yue WANG Junping zhang Shanghai Key Laboratory of Intelligent Information Processing School of Computer ScienceFudan UniversityShanghai 200433China Institute of Science and Technology for Brain-inspired Intelligence Fudan UniversityShanghai 200433China Shanghai Center for Brain Science and Brain-inspired Technology Shanghai 201210China School of Information Science and Technology Xiamen UniversityXiamen 361005China College of Information Sciences and Technology the Pennsylvania State UniversityUniversity ParkPA 16802USA State Key Laboratory of Management and Control for Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China

Crowd counting has important applications in public safety and pandemic control.A robust and practical crowd counting system has to be capable of continuously learning with the newly incoming domain data in real-world scenarios instead of fitting one domain ***-the-shelf methods have some drawbacks when handling multiple domains:(1)the models will achieve limited performance(even drop dramatically)among old domains after training images from new domains due to the discrepancies in intrinsic data distributions from various domains,which is called catastrophic forgetting;(2)the well-trained model in a specific domain achieves imperfect performance among other unseen domains because of domain shift;(3)it leads to linearly increasing storage overhead,either mixing all the data for training or simply training dozens of separate models for different domains when new ones are *** overcome these issues,we investigate a new crowd counting task in incremental domain training setting called lifelong crowd *** goal is to alleviate catastrophic forgetting and improve the generalization ability using a single model updated by the incremental ***,we propose a self-distillation learning framework as a benchmark(forget less,count better,or FLCB)for lifelong crowd counting,which helps the model leverage previous meaningful knowledge in a sustainable manner for better crowd counting to mitigate the forgetting when new data arrive.A new quantitative metric,normalized Backward Transfer(nBwT),is developed to evaluate the forgetting degree of the model in the lifelong learning *** experimental results demonstrate the superiority of our proposed benchmark in achieving a low catastrophic forgetting degree and strong generalization ability.

关键词： Crowd counting Knowledge distillation Lifelong learning

ASF1 regulates asexual and sexual reproduction in Stemphylium eturmiunum by DJ-1 stimulation of the PI3K/AKT signaling pathway

在线全文

学校读者我要写书评

暂无评论

Fungal Diversity 2023年第6期123卷 159-176页

作者： Shi Wang Xiaoman Liu Chenlin Xiong Susu Gao Wenmeng Xu Lili Zhao Chunyan Song Xiaoyong Liu Timothy y.james Zhuang Li Xiuguo zhang College of Life Sciences Shandong Normal UniversityJinan 250014China Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests College of Plant ProtectionShandong Agricultural UniversityTaian 271018China Department of Ecology and Evolutionary Biology University of MichiganAnn ArborMI 48109-1048USA

Most fungi display a mixed mating system with both asexual and sexual *** timing of the two modes of reproduction must be carefully coordinated through signal perception and coordination in the cell along with chromatin ***,we investigated coordination of reproductive output by investigating the function of the histone chaper-one anti-silencing factor 1(ASF1)in a fungal species amenable to characterization of both asexual and sexual *** used knockout approach to show that SeASF1 influenced asexual and sexual reproduction in Stemphylium ***1-deleted strains failed to produce pseudothecia,but produce abnormal conidia and showed an irregular distribution of nuclei in *** sequencing was then used to identify genes with altered expression in the SeASF1-deleted *** transcriptional expression of the identified SeDJ-1 was strongly regulated by *** interaction of SeDJ-1 and SeASF1 was confirmed using y2H,Co-IP,and *** to some components of phosphatidylinositol 3-kinase/protein kinase B(PI3K/AKT)signaling pathway were known to interact with DJ-1 in mammals,we verified SePI3K,an element of PI3K/AKT signaling pathway in ***,was directly linked to SeDJ-1 and then these two proteins were defined as a coordinator of ***,knockout of SeDJ-1 or SePI3K altered the asexual and sexual repro-duction,but SePI3K recovered the asexual and sexual development of∆*** SeDJ-1-M6 segment of SeDJ-1 was essential for its interaction with SePI3K and played a critical role in restoring sexual reproduction in the∆Sepi3k,providing a deep understanding of the regulatory mechanism of SeDJ-1 in *** ***,SeASF1 is able to trigger SeDJ-1 and SeDJ-1can also activate SePI3K,which is orchestrally involved in asexual and sexual reproduction in *** these results reveal that SeASF1 manipulates asexual and sexual reproduction in *** by SeDJ

关键词： ASF1 DJ-1 Stemphylium eturmiunum PI3K/AKT signaling pathway Asexual and sexual reproduction

Spatiotemporal variation of agricultural patterns in different geomorphologic and climatic environments in the eastern Loess Plateau,north-central China during the late Neolithic and Bronze Ages

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Earth Sciences 2022年第5期65卷 934-948页

作者： Haiming LI yifu CUI Nathaniel james Melissa RITCHEy Fengwen LIU Junna zhang Minmin MA Guanghui DONG College of Humanities&Social Development Nanjing Agricultural UniversityNanjing 210095China Institution of Chinese Agricultural Civilization Nanjing Agricultural UniversityNanjing 210095China Agricultural Archaeology Research Center Nanjing Agricultural UniversityNanjing 210095China College of Tourism Huaqiao UniversityQuanzhou 362021China Ministry of Education Key Laboratory of Western China’s Environmental System College of Earth&Environmental SciencesLanzhou UniversityLanzhou 730000China Department of Anthropology University of California San DiegoSan DiegoCA 92093USA Department of Anthropology Washington University in St.LouisSt.LouisMO 63130USA Institute for Ecological Research and Pollution Control of Plateau Lakes School of Ecology and Environment ScienceYunnan UniversityKunming 650504China Laboratory for Environmental Archaeology Archaeological Research CenterBeijing Union UniversityBeijing 100191China

Human settlement and agricultural development are closely linked to local geomorphological and climatic ***,the variation in agricultural systems in different environmental and prehistoric contexts remains *** report new archaeobotanical and radiocarbon dates from 34 Neolithic and Bronze Age sites in the Hutuo River Valley(HTRV)in north-central China and compare them with updated archaeobotanical studies in the Sushui River Valley(SSRV)and Henan Province(HNP),to explore the similarities and differences of agricultural patterns under different geomorphologic and climatic environments in north-central *** results reveal that humans consistently cultivated foxtail and broomcorn millet in the HTRV from the Miaodigou(6000–5700 cal.a BP)to the Shang-Zhou(3600–2256 cal.a BP)period,despite the introduction of wheat and barley into the area around 4000 a *** conditions and hilly landforms in the HTRV,SSRV and some parts of the HNP led people to develop foxtail and broomcorn millet dry land farming practices between 7000 and 3000 a ***,in other areas of the HNP,the climate conditions and alluvial plains enabled people to develop a mixed agriculture of millets,soybeans,and rice from 7000 to 4000 a BP,with the addition of wheat between 4000 and 3000 a ***’different agricultural technologies and interactions with foreign cultures may have also influenced the formation of different agricultural patterns in the three regions between 7000 and 3000 a *** growth during 7000–3000 a BP can explain the overall propensity of the higher-yield foxtail millet rather than broomcorn millet as the main cultivated *** the HTRV,however,higher proportions of broomcorn millet(as compared to the SSRV and HNP),may reflect the greater drought and heat tolerance of broomcorn millet,representing an adaptive agricultural strategy in the river valley.

关键词： Archaeobotanical Agricultural patterns Climate conditions Hilly area Alluvial plains