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Plant-substrate biochar properties critical for mediating reductive debromination of 1,2-dibromoethane

Journal of Environmental Sciences 2025年第1期147卷 1-10页

作者： Jonathan h.Lindhardt Peter E.holm Yong-Guan Zhu Changyong Lu hans Christian b.hansen Department of Plant and Environmental Sciences Faculty of ScienceUniversity of CopenhagenThorvaldsensvej 401871 Frederiksberg CDenmark Key lab of Urban Environment and health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Sino-Danish Center for education and research China and DenmarkDalgas Avenue 4DK-8000 Aarhus C.Denmark

Dibromoethane is a widespread,persistent organic *** are known mediators of reductive dehalogenation by layered Fe^(Ⅱ)-Fe^(Ⅲ)hydroxides(green rust),which can reduce 1,2-dibromoethane to innocuous bromide and ***,the critical characteristics that determine mediator functionality are lesser *** biochar substrates were pyrolyzed at 600℃and 800℃,characterized by elemental analysis,X-ray photo spectrometry C and N surface speciation,X-ray powder diffraction,specific surface area analysis,and tested for mediation of reductive debromination of 1,2-dibromoethane by a green rust reductant under anoxic conditions.A statistical analysis was performed to determine the biochar properties,critical for debromination kinetics and total debromination *** was shown that selected plant based biochars can mediate debromination of 1,2-dibromoethane,that the highest first order rate constant was 0.082/hr,and the highest debromination extent was 27%in reactivity experiments with 0.1μmol(20μmol/L)1,2-dibromoethane,≈22 mmol/L Fe^(Ⅱ)GR,and 0.12 g/L soybean meal biochar(7 days).Contents of Ni,Zn,N,and P,and the relative contribution of quinone surface functional groups were significantly(ph 1,2-dibromoethane debromination,while adsorption,specific surface area,and the relative contribution of pyridinic N oxide surface groups were significantly negatively correlated with debromination.

关键词： Environmental remediation biochar Persistent organic pollutants(POPs) Environmental catalysis Green rust

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Characterization and source apportionment of volatile organic compounds in hong Kong:A 5-year study for three different archetypical sites

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Journal of Environmental Sciences 2025年第5期151卷 424-440页

作者： Yuchen Mai Vincent Cheung Peter K.K.Louie Kenneth Leung Jimmy C.h.Fung Alexis K.h.Lau Donald R.b.lake Dasa Gu Division of Environment and Sustainability The Hong Kong University of Science and TechnologyHong Kong 999077China Environmental Protection Department Hong Kong 999077China Environment and Ecology bureau Hong Kong 999077China Department of Chemistry University of CaliforniaIrvine 92617USA

Initial success has been achieved in hong Kong in controlling primary air pollutants,but ambient ozone levels kept increasing during the past three *** organic compounds(VOCs)are important for mitigating ozone pollution as its major *** study analyzed VOC characteristics of roadside,suburban,and rural sites in hong Kong to investigate their compositions,concentrations,and source *** showthat the TVOC concentrations were 23.05±13.24,12.68±15.36,and 5.16±5.48 ppbv for roadside,suburban,and rural sites between May 2015 to June 2019,*** using Positive Matrix Factorization(PMF)model,six sources were identified at the roadside site over five years:Liquefied petroleum gas(LPG)usage(33%–46%),gasoline evaporation(8%–31%),aged air mass(11%–28%),gasoline exhaust(5%–16%),diesel exhaust(2%–16%)and fuel filling(75–9%).Similarly,six sources were distinguished at the suburban site,including LPG usage(30%–33%),solvent usage(20%–26%),diesel exhaust(14%–26%),gasoline evaporation(8%–16%),aged air mass(4%–11%),and biogenic emissions(2%–5%).At the rural site,four sources were identified,including aged airmass(33%–51%),solvent usage(25%–30%),vehicular emissions(11%–28%),and biogenic emissions(6%–12%).The analysis further revealed that fuel filling and LPG usage were the primary contributors to OFP and Oh reactivity at the roadside site,while solvent usage and biogenic emissions accounted for almost half of OFP and Oh reactivity at the suburban and rural sites,*** findings highlight the importance of identifying and characterizing VOC sources at different sites to help policymakers develop targeted measures for pollution mitigation in specific areas.

关键词： Volatile organic compounds Positive matrix factorization Source apportionment Ozone formation

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Measurement of the integrated luminosity of the Phase 2 data of the belle Ⅱ experiment

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Chinese Physics C 2020年第2期44卷 1-12页

作者： F.Abudinén I.Adachi P.Ahlburg h.Aihara N.Akopov A.Aloisio F.Ameli L.Andricek N.Anh Ky D.M.Asner h.Atmacan T.Aushev V.Aushev T.Aziz K.Azmi V.babu S.baehr S.bahinipati A.M.bakich P.bambade Sw.banerjee S.bansal V.bansal M.barrett J.baudot A.beaulieu J.becker P.K.behera J.V.bennett E.bernieri F.U.bernlochner M.bertemes M.bessner S.bettarini V.bhardwaj F.bianchi T.bilka S.bilokin D.biswas G.bonvicini A.bozek M.bračko P.branchini N.braun T.E.browder A.budano S.bussino M.Campajola L.Cao G.Casarosa C.Cecchi D.Červenkov M.-C.Chang P.Chang R.Cheaib V.Chekelian Y.Q.Chen Y.-T.Chen b.G.Cheon K.Chilikin h.-E.Cho K.Cho S.Cho S.-K.Choi S.Choudhury D.Cinabro L.Corona L.M.Cremaldi S.Cunliffe T.Czank F.Dattola E.De La Cruz-burelo G.De Nardo M.De Nuccio G.De Pietro R.de Sangro M.Destefanis S.Dey A.De Yta-hernandez F.Di Capua S.Di Carlo J.Dingfelder Z.Doležal I.Domínguez Jiménez T.V.Dong K.Dort S.Dubey S.Duell S.Eidelman M.Eliachevitch T.Ferber D.Ferlewicz G.Finocchiaro S.Fiore A.Fodor F.Forti A.Frey b.G.Fulsom M.Gabriel E.Ganiev M.Garcia-hernandez R.Garg A.Garmash V.Gaur A.Gaz U.Gebauer A.Gellrich J.Gemmler T.Geßler R.Giordano A.Giri b.Gobbo R.Godang P.Goldenzweig b.Golob P.Gomis P.Grace W.Gradl E.Graziani D.Greenwald C.hadjivasiliou S.halder K.hara T.hara O.hartbrich K.hayasaka h.hayashii C.hearty M.T.hedges I.heredia de la Cruz M.hernández Villanueva A.hershenhorn T.higuchi E.C.hill h.hirata M.hoek S.hollitt T.hotta C.-L.hsu Y.hu K.huang T.Iijima K.Inami G.Inguglia J.Irakkathil Jabbar A.Ishikawa R.Itoh M.Iwasaki Y.Iwasaki S.Iwata P.Jackson W.W.Jacobs D.E.Jaffe E.-J.Jang h.b.jeon S.Jia Y.Jin C.Joo J.Kahn h.Kakuno A.b.Kaliyar G.Karyan Y.Kato T.Kawasaki h.Kichimi C.Kiesling b.h.Kim C.-h.Kim D.Y.Kim S.-h.Kim Y.K.Kim Y.Kim T.D.Kimmel K.Kinoshita C.Kleinwort b.Knysh P.Kodyš T.Koga I.Komarov T.Konno S.Korpar D.Kotchetkov N.Kovalchuk T.M.G.Kraetzschmar P.Križan R.Kroeger J.F.Krohn P.Krokovny W.Kuehn T.Kuhr M.Kumar R.Kumar K.Kumara S.Kurz A.Kuzmin Y.-J.Kwon S.Lacaprara Y.-T.Lai C.La Licata K.Lalwani L.Lanceri J.S.Lange K.Lautenbach I.-S.Le beihang University Beijing 100191 brookhaven National Laboratory UptonNew York 11973 budker Institute of Nuclear Physics Sb RAS Novosibirsk 630090 Centro de Investigacion y de Estudios Avanzados del Instituto Politecnico Nacional Mexico City 07360 Faculty of Mathematics and Physics Charles University12116 Prague Chiba University Chiba 263-8522 Consejo Nacional de Ciencia y Tecnología Mexico City 03940 Deutsches Elektronen–Synchrotron 22607 Hamburg Duke University DurhamNorth Carolina 27708 Earthquake Research Institute University of TokyoTokyo 113-0032 Forschungszentrum Jülich 52425 Jülich Department of Physics Fu Jen Catholic UniversityTaipei 24205 Key Laboratory of Nuclear Physics and Ion-beam Application(MOE)and Institute of Modern Physics Fudan UniversityShanghai 200443 II.Physikalisches Institut Georg-August-Universität Göttingen37073 Göttingen Gifu University Gifu 501-1193 The Graduate University for Advanced Studies(SOKENDAI) Hayama 240-0193 Gyeongsang National University Jinju 52828 Department of Physics and Institute of Natural Sciences Hanyang UniversitySeoul 04763 high Energy Accelerator Research Organization(KEK) Tsukuba 305-0801 J-PARC branch KEK Theory CenterHigh Energy Accelerator Research Organization(KEK)Tsukuba 305-0801 Indian Institute of Science Education and Research Mohali SAS Nagar140306 Indian Institute of Technology bhubaneswar Satya Nagar 751007 Indian Institute of Technology hyderabad Telangana 502285 Indian Institute of Technology Madras Chennai 600036 Indiana University BloomingtonIndiana 47408 Institute for high Energy Physics Protvino 142281 Institute of high Energy Physics Vienna 1050 Institute of high Energy Physics Chinese Academy of SciencesBeijing 100049 Institute of Particle Physics(Canada) VictoriaBritish Columbia V8W 2Y2 Institute of Physics Hanoi Instituto de Fisica Corpuscular Paterna 46980 INFN Laboratori Nazionali di Frascati I-00044 Frascati INFN Sezione di Napoli I-80126 Napoli INFN Sezione di Padova I-35131 Padova INFN Sezione di Perugia I-06123 Perugia

From April to July 2018,a data sample at the peak energy of the T(4 S) resonance was collected with the belle Ⅱ detector at the SuperKEKb electron-positron *** is the first data sample of the belle Ⅱ *** bhabha and digamma events,we measure the integrated luminosity of the data sample to be(496.3±0.3±3.0) pb-1,where the first uncertainty is statistical and the second is *** work provides a basis for future luminosity measurements at belle Ⅱ.

关键词： luminosity bhabha digamma belle II

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ON ThE GAUSSIAN KINEMATIC FORMULA OF *** AND ***

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Acta Mathematica Scientia 2025年第1期45卷 200-214页

作者： Joseph h.G.Fu Department of Mathematics University of GeorgiaAthensGA30602USA

We apply methods of algebraic integral geometry to prove a special case of the Gaussian kinematic formula of *** idea,suggested already by Adler and Taylor,is to view the GKF as the limit of spherical kinematic formul... 详细信息

关键词： integral geometry kinematic formula probability density Gaussian density

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植物系统发生海报——以演化视角介绍植物多样性的科教资料项目

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生物多样性 2025年

作者：蒋陈焜郁文彬饶广远黎怀成 Julien b.bachelier hartmut h.hilger Theodor C.h.Cole 北京大学生命科学学院蛋白质与植物基因研究国家重点实验室北京大学前沿交叉学科研究院北京大学-清华大学生命科学联合中心中国科学院西双版纳热带植物园综合保护中心/云南省热带雨林与亚洲象保护重点实验室 Dahlem Centre of Plant Sciences (DCPS)， Institute of biology， Structural and Functional Plant Diversity， Freie Universit?t berlin

中国的植物多样性保护行动虽然提升了公众对多样性的认识，但这些努力往往未能深入到理解植物多样性演化及其保护的深层意义。从演化的视角进行植物多样性宣传教育，有利于促进对多样性的综合理解，增进对多样性保护的认可。然而， ... 详细信息

中国的植物多样性保护行动虽然提升了公众对多样性的认识，但这些努力往往未能深入到理解植物多样性演化及其保护的深层意义。从演化的视角进行植物多样性宣传教育，有利于促进对多样性的综合理解，增进对多样性保护的认可。然而，现有资料多集中于物种的识别、鉴定与分类，缺乏从生物演化角度对植物多样性进行系统性介绍的内容。本文介绍了一个具有全球影响力的科教资料案例——由美裔德国植物学家Theodor C. h. Cole发起的植物系统发生海报(Plant Phylogeny Posters)项目。该项目通过整合最新的系统与演化植物学研究成果，以系统发生为线索介绍植物多样性及其亲缘关系，旨在利用系统发生树所蕴含的丰富演化思想内涵，启发读者理解植物多样性与演化。海报以系统发生树结合植物类群的形态、地理分布、物种数量等数据信息，直观展示了多个分类等级的重要类群的演化历史。在数十所大学和科研机构的45位研究人员的努力下， 70张系统发生海报已被翻译成中文，并向所有人免费开放获取。这一科教项目有望为增进公众深入理解植物多样性及其保护行动提供宝贵的资源和帮助。

关键词：植物多样性演化系统发生科教资料

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hydrogen production from dry reforming of methane,using CO_(2)previously chemisorbed in the Li_(6)Zn_(1-x)Ni_(x)O_(4)solid solution

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Journal of Environmental Sciences 2025年第3期149卷 535-550页

作者： Yocelin b.González-González Fernando Plascencia-hernández Rubén Mendoza-Cruz heriberto Pfeiffer Instituto de Investigaciones en Materiales Universidad Nacional Autónoma de MéxicoCircuito exterior s/nCiudad UniversitariaDel.CoyoacánCP 04510CdMxMexico

Li_(6)ZnO_(4)was chemically modified by nickel addition,in order to develop different compositions of the solid solution Li_(6)Zn_(1-x)Ni_(x)O_(4).These materials were evaluated bifunctionally;analyzing their CO_(2)capture performances,aswell as on their catalytic properties for h_(2)production via dry reforming of methane(DRM).The crystal structures of Li_(6)Zn_(1-x)Ni_(x)O_(4)solid solution samples were determined through X-ray diffraction,which confirmed the integration of nickel ions up to a concentration around 20 mol%,meanwhile beyond this value,a secondary phase was *** results were supported by XPS and TEM ***,dynamic and isothermal thermogravimetric analyses of CO_(2)capture revealed that Li_(6)Zn_(1-x)Ni_(x)O_(4)solid solution samples exhibited good CO_(2)chemisorption efficiencies,similarly to the pristine Li_(6)ZnO_(4)chemisorption trends ***,a kinetic analysis of CO_(2)isothermal chemisorptions,using the Avrami-Erofeev model,evidenced an increment of the constant rates as a function of the Ni *** Ni^(2+)ions incorporation did not reduce the CO_(2)capture efficiency and kinetics,the catalytic properties of thesematerialswere evaluated in the DRM *** demonstrated that nickel ions favored hydrogen(h_(2))production over the pristine Li_(6)ZnO_(4)phase,despite a second h2 production reaction was determined,methane ***,Li_(6)Zn_(1-x)Ni_(x)O_(4)ceramics can be employed as bifunctional materials.

关键词： Dry reforming of methane(DRM) CO_(2)chemisorption h_(2)production Solid solution Li_(6)ZnO_(4)

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Deep view of composite SNR CTA1 with LhAASO in γ-rays up to 300 TeV

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Science China(Physics,Mechanics & Astronomy) 2025年

作者： Zhen Cao F.Aharonian Axikegu Y.X.bai Y.W.bao D.bastieri X.J.bi Y.J.bi W.bian A.V.bukevich Q.Cao W.Y.Cao Zhe Cao J.Chang J.F.Chang A.M.Chen E.S.Chen h.X.Chen Liang Chen Lin Chen Long Chen M.J.Chen M.L.Chen Q.h.Chen S.Chen S.h.Chen S.Z.Chen T.L.Chen Y.Chen N.Cheng Y.D.Cheng M.C.Chu M.Y.Cui S.W.Cui X.h.Cui Y.D.Cui b.Z.Dai h.L.Dai Z.G.Dai Danzengluobu X.Q.Dong K.K.Duan J.h.Fan Y.Z.Fan J.Fang J.h.Fang K.Fang C.F.Feng h.Feng L.Feng S.h.Feng X.T.Feng Y.Feng Y.L.Feng S.Gabici b.Gao C.D.Gao Q.Gao W.Gao W.K.Gao M.M.Ge T.T.Ge L.S.Geng G.Giacinti G.h.Gong Q.b.Gou M.h.Gu F.L.Guo J.Guo X.L.Guo Y.Q.Guo Y.Y.Guo Y.A.han O.A.hannuksela M.hasan h.h.he h.N.he J.Y.he Y.he Y.K.hor b.W.hou C.hou X.hou h.b.hu Q.hu S.C.hu C.huang D.h.huang T.Q.huang W.J.huang X.T.huang X.Y.huang Y.huang Y.Y.huang X.L.Ji h.Y.Jia K.Jia h.b.Jiang K.Jiang X.W.Jiang Z.J.Jiang M.Jin M.M.Kang I.Karpikov D.Khangulyan D.Kuleshov K.Kurinov b.b.Li C.M.Li Cheng Li Cong Li D.Li F.Li h.b.Li h.C.Li Jian Li Jie Li K.Li S.D.Li W.L.Li W.L.Li X.R.Li Xin Li Y.Z.Li Zhe Li Zhuo Li E.W.Liang Y.F.Liang S.J.Lin b.Liu C.Liu D.Liu D.b.Liu h.Liu h.D.Liu J.Liu J.L.Liu M.Y.Liu R.Y.Liu S.M.Liu W.Liu Y.Liu Y.N.Liu Q.Luo Y.Luo h.K.Lv b.Q.Ma L.L.Ma X.h.Ma J.R.Mao Z.Min W.Mitthumsiri h.J.Mu Y.C.Nan A.Neronov K.C.Y.Ng L.J.Ou P.Pattarakijwanich Z.Y.Pei J.C.Qi M.Y.Qi b.Q.Qiao J.J.Qin A.Raza D.Ruffolo A.Sáiz M.Saeed D.Semikoz L.Shao O.Shchegolev X.D.Sheng F.W.Shu h.C.Song Yu.V.Stenkin V.Stepanov Y.Su D.X.Sun Q.N.Sun X.N.Sun Z.b.Sun J.Takata P.h.T.Tam Q.W.Tang R.Tang Z.b.Tang W.W.Tian L.h.Wan C.Wang C.b.Wang G.W.Wang h.G.Wang h.h.Wang J.C.Wang Kai Wang Kai Wang L.P.Wang L.Y.Wang P.h.Wang R.Wang W.Wang X.G.Wang X.Y.Wang Y.Wang Y.D.Wang Y.J.Wang Z.h.Wang Z.X.Wang Zhen Wang Zheng Wang D.M.Wei J.J.Wei Y.J.Wei T.Wen C.Y.Wu h.R.Wu Q.W.Wu S.Wu X.F.Wu Y.S.Wu S.Q.Xi J.Xia G.M.Xiang D.X.Xiao G.Xiao Y.L.Xin Y.Xing D.R.Xiong Z.Xiong D.L.Xu R.F.Xu R.X.Xu W.L.Xu L.Xue D.h.Yan J.Z.Yan T.Yan C.W.Yang C.Y.Yang F.Yang F.F.Yang L.L.Yang M.J.Yang R.Z.Yang W.X.Yang Y.h.Yao Z.G.Yao L.Q.Yin N.Yin X.h.You Z.Y.You Y.h Southwest Jiaotong University School of Astronomy and Space Science Nanjing University Center for Astrophysics Guangzhou University Tsung-Dao Lee Institute & School of Physics and Astronomy Shanghai Jiao Tong University Institute for Nuclear Research of Russian Academy of Sciences hebei Normal University University of Science and Technology of China LhAASO Collaboration State Key Laboratory of Particle Detection and Electronics Key Laboratory of Dark Matter and Space Astronomy & Key Laboratory of Radio Astronomy Purple Mountain Observatory Chinese Academy of Sciences Research Center for Astronomical Computing Zhejiang Laboratory Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences School of Physics and Astronomy Key Laboratory of Particle Astrophysics & Experimental Physics Division & Computing Center Yunnan University Key Laboratory of Cosmic Rays (Tibet University) Ministry of Education Department of Physics The Chinese University of hong Kong Key Laboratory of Radio Astronomy and Technology National Astronomical Observatories Chinese Academy of Sciences School of Physics and Astronomy (Zhuhai) & School of Physics (Guangzhou) & Sino-French Institute of Nuclear Engineering and Technology (Zhuhai) Sun Yat-sen University Institute of high Energy Physics Institute of Frontier and Interdisciplinary Science Shandong University APC Université Paris Cité CNRS/IN2P3 CEA/IRFU Observatoire de Paris Department of Engineering Physics & Department of Astronomy Tsinghua University School of Physics and Microelectronics Chinese Academy of Sciences Zhengzhou University Yunnan Observatories Chinese Academy of Sciences China Center of Advanced Science and Technology College of Physics Sichuan University School of Physics Peking University Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and Technology University of Chinese Academy of Sciences Guangxi University Department of Physics Faculty of Science Mahidol University Moscow Institute

The ultra-high-energy（UhE） gamma-ray source 1LhAASO J0007+7303u is positionally associated with the composite SNR CTA1 that is located at high Galactic Latitude b ≈ 10.5°. This provides a rare opportunity to spatially resolve the component of the pulsar wind nebula（PWN） and supernova remnant（SNR） at UhE. This paper conducted a dedicated data analysis of 1LhAASO J0007+7303u using the data collected from December 2019 to July 2023. This source is well detected with significances of 21σ and 17σ at 8-100 TeV and >100 TeV, respectively. The corresponding extensions are determined to be 0.23°±0.03°and 0.17°±0.03°. The emission is proposed to originate from the relativistic electrons accelerated within the PWN of PSR J0007+7303. The energy spectrum is well described by a power-law with an exponential cutoff function dN/dE =（42.4 ± 4.1）(E/（20 TeV）)-2.31±0.11exp(-E/（110±25 TeV）) TeV-1cm-2s-1in the energy range from 8 to 300 TeV, implying a steady-state parent electron spectrum dNe/dEe∝(Ee/（100 TeV）)-3.13±0.16exp[(-Ee/（373±70 TeV）)2] at energies above ≈ 50 TeV. The cutoff energy of the electron spectrum is roughly equal to the expected current maximum energy of particles accelerated at the PWN terminal shock. Combining the X-ray and gamma-ray emission, the current space-averaged magnetic field can be limited to≈ 4.5 μG. To satisfy the multi-wavelength spectrum and the γ-ray extensions, the transport of relativistic particles within the PWN is likely dominated by the advection process under the free-expansion phase assumption.

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LhAASO detection of very-high-energy γ-ray emission surrounding PSR J0248+6021

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Science China(Physics,Mechanics & Astronomy) 2025年

We report the detection of an extended very-high-energy(VhE) γ-ray source coincident with the location of middle-aged(62.4 kyr) pulsar PSR J0248+6021, by using the LhAASO-WCDA data of live 796 d and LhAASO-KM2A data of live 1216d. A significant excess of γ-ray induced showers is observed both by WCDA in energy bands of 1-25 Te V and KM2A in energy bands of >25 TeV with 7.3σ and 13.5σ, respectively. The best-fit position derived through WCDA data is R.A. = 42.06°± 0.12°and Dec. = 60.24°± 0.13°with an extension of 0.69°±0.15°and that of the KM2A data is R.A.= 42.29°± 0.13°and Dec. =60.38°± 0.07°with an extension of 0.37°±0.07°. No clear extended multiwavelength counterpart of this LhAASO source has been found from the radio band to the GeV band. The most plausible explanation of the VhE γ-ray emission is the inverse Compton process of highly relativistic electrons and positrons injected by the pulsar. These electrons/positrons are hypothesized to be either confined within the pulsar wind nebula or to have already escaped into the interstellar medium, forming a pulsar halo.

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Observation of the γ-ray emission from W43 with LhAASO

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Science China(Physics,Mechanics & Astronomy) 2025年

In this paper, we report the detection of the very-high-energy (VhE, 100 Ge V100 TeV) γ-ray emissions from the direction of the young star-forming region W43, observed by the Large high Altitude Air Shower Observation (LhAASO). The extended γ-ray source was detected with a significance of～16σby KM2A and～17σby WCDA, respectively. The angular extension of this γ-ray source is about 0.5 degrees, corresponding to a physical size of about 50pc. We discuss the origin of the γ-ray emission and possible cosmic ray acceleration in the W43 region using multi-wavelength data. Our findings suggest that W43 is likely another young star cluster capable of accelerating cosmic rays (CRs) to at least several hundred TeV.

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A Privacy-Preserving Image Retrieval based on AC-Coefficients and Color histograms in Cloud Environment

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Computers, Materials & Continua 2019年第1期58卷 27-43页

作者： Zhihua Xia Lihua Lu Tong Qiu h.J.Shim Xianyi Chen byeungwoo jeon Jiangsu Engineering Centre of Network Monitoring Jiangsu Collaborative Innovation Center on Atmospheric Environment and Equipment TechnologySchool of Computer and SoftwareNanjing University of Information Science&TechnologyNanjing210044China College of Information&Communication Engineering Sungkyunkwan UniversityKorea

Content based image retrieval(CbIR)techniques have been widely deployed in many applications for seeking the abundant information existed in *** to large amounts of storage and computational requirements of CbIR,outsourcing image search work to the cloud provider becomes a very attractive option for many owners with small ***,owing to the private content contained in images,directly outsourcing retrieval work to the cloud provider apparently bring about privacy problem,so the images should be protected carefully before *** paper presents a secure retrieval scheme for the encrypted images in the YUV color *** this scheme,the discrete cosine transform(DCT)is performed on the Y *** resulting DC coefficients are encrypted with stream cipher technology and the resulting AC coefficients as well as other two color components are encrypted with value permutation and position *** the image owner transmits the encrypted images to the cloud *** receiving a query trapdoor form on query user,the server extracts AC-coefficients histogram from the encrypted Y component and extracts two color histograms from the other two color *** similarity between query trapdoor and database image is measured by calculating the Manhattan distance of their respective ***,the encrypted images closest to the query image are returned to the query user.

关键词： Image retrieval AC-coefficients histogram color histogram discrete cosine transform

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