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基于NUFER-village模型分析洱海流域不同农牧系统氮素流动特征
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作者 李志刚 郑毅 +5 位作者 梁启斌 王艳霞 侯磊 李晓琳 胡丹 王晶 《农业环境科学学报》 北大核心 2025年第2期471-482,共12页
为分析洱海流域农牧系统的氮素流动特征,明确不同类型农牧系统氮素损失差异,依据农村主要产业发展类型,将洱海流域村庄划分为种植型、养殖型和农牧结合型3大类型,并进一步依据主要种植作物类型、畜禽养殖类型以及不同种养结合形式,划分1... 为分析洱海流域农牧系统的氮素流动特征,明确不同类型农牧系统氮素损失差异,依据农村主要产业发展类型,将洱海流域村庄划分为种植型、养殖型和农牧结合型3大类型,并进一步依据主要种植作物类型、畜禽养殖类型以及不同种养结合形式,划分16个亚类。最后运用村级尺度的食物链养分流动模型(Nutrient flows in food chain,environment and resources use,NUFER)定量洱海流域不同农牧系统氮素投入特征、养分利用效率及环境流失特征。结果表明:洱海流域单位产品氮素投入量以养殖型最高(5.65~8.92 t),农牧结合型最低(1.92~2.96 t)。其中养殖型以养殖羊亚类氮素投入最高,农牧结合型中以林果+羊亚类投入最低;氮素利用效率从高到低分别为种植型(30.0%~48.8%)、农牧结合型(19.0%~30.8%)、养殖型(5.5%~10.4%)。种植型、农牧结合型、养殖型对应的最高氮素利用效率亚类分别为玉米、林果+羊、家禽;单位产品氮素环境排放量以养殖型最高(5.22~9.03 t),农牧结合型最低(0.66~1.27 t)。其中养殖型以养殖羊亚类氮单位产品氮素环境排放量最高,而农牧结合型中立体种养模式均较低(0.66~0.86 t)。氨挥发是所有类型农村农牧系统主要环境排放形式。洱海西部和北部存在较多高污染排放村,环境风险大,且高污染村以畜禽养殖为主。洱海流域农牧体系氮素投入量较高且养分利用率处于较低水平,环境排放强度高,未来可结合高原湖泊流域特征,进一步推行立体种养模式,从而实现区域农牧系统与环境保护协同的高效发展。 展开更多
关键词 农牧系统 NUFER-village模型 洱海流域 氮素流失 立体种养
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Call for Papers from Agricultural Products Processing and Storage
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《肉类研究》 北大核心 2025年第9期I0017-I0017,共1页
Agricultural Products Processing and Storage(ISSN 3059-4510,Owner:Hunan Academy of Agricultural Sciences,China.Production and hosting:Springer Nature)is an international,peer-reviewed open access journal with the aim ... Agricultural Products Processing and Storage(ISSN 3059-4510,Owner:Hunan Academy of Agricultural Sciences,China.Production and hosting:Springer Nature)is an international,peer-reviewed open access journal with the aim to offer a platform for the rapid dissemination of signifi cant,novel,and high-impact research in the fi elds of agricultural product processing science,technology,engineering,and nutrition.Additionally,supplemental issues are curated and published to facilitate in-depth discussions on special topics. 展开更多
关键词 NUTRITION SCIENCE agricultural products open access journal agricultural products processing STORAGE technology engineering
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Call for Papers from Agricultural Products Processing and Storage
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《肉类研究》 北大核心 2025年第10期I0017-I0017,共1页
Agricultural Products Processing and Storage(ISSN 3059-4510,Owner:Hunan Academy of Agricultural Sciences,China.Production and hosting:Springer Nature)is an international,peer-reviewed open access journal with the aim ... Agricultural Products Processing and Storage(ISSN 3059-4510,Owner:Hunan Academy of Agricultural Sciences,China.Production and hosting:Springer Nature)is an international,peer-reviewed open access journal with the aim to offer a platform for the rapid dissemination of signifi cant,novel,and high-impact research in the fi elds of agricultural product processing science,technology,engineering,and nutrition.Additionally,supplemental issues are curated and published to facilitate in-depth discussions on special topics. 展开更多
关键词 NUTRITION SCIENCE agricultural products open access journal agricultural products processing STORAGE technology engineering
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Call for Papers from Agricultural Products Processing and Storage
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《肉类研究》 北大核心 2025年第11期I0017-I0017,共1页
Agricultural Products Processing and Storage(ISSN 3059-4510,Owner:Hunan Academy of Agricultural Sciences,China.Production and hosting:Springer Nature)is an international,peer-reviewed open access journal with the aim ... Agricultural Products Processing and Storage(ISSN 3059-4510,Owner:Hunan Academy of Agricultural Sciences,China.Production and hosting:Springer Nature)is an international,peer-reviewed open access journal with the aim to offer a platform for the rapid dissemination of signifi cant,novel,and high-impact research in the fi elds of agricultural product processing science,technology,engineering,and nutrition.Additionally,supplemental issues are curated and published to facilitate in-depth discussions on special topics. 展开更多
关键词 NUTRITION SCIENCE agricultural products open access journal agricultural products processing STORAGE technology engineering
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Call for Papers from Agricultural Products Processing and Storage
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《食品科学》 北大核心 2025年第20期I0022-I0022,共1页
Agricultural Products Processing and Storage(ISSN 3059-4510,Owner:Hunan Academy of Agricultural Sciences,China.Production and hosting:Springer Nature)is an international,peer-reviewed open access journal with the aim ... Agricultural Products Processing and Storage(ISSN 3059-4510,Owner:Hunan Academy of Agricultural Sciences,China.Production and hosting:Springer Nature)is an international,peer-reviewed open access journal with the aim to offer a platform for the rapid dissemination of signifi cant,novel,and high-impact research in the fi elds of agricultural product processing science,technology,engineering,and nutrition.Additionally,supplemental issues are curated and published to facilitate in-depth discussions on special topics. 展开更多
关键词 NUTRITION SCIENCE agricultural products open access journal agricultural products processing STORAGE technology engineering
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Call for Papers from Food Science of Animal Products
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《食品科学》 北大核心 2025年第8期I0028-I0028,共1页
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food mater... Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects. 展开更多
关键词 Food Science Animal products
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Public-Key Function-Private Inner-Product Predicate Encryption from Pairings
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作者 WAN Ming WANG Geng GU Da-Wu 《密码学报(中英文)》 北大核心 2025年第1期227-246,共20页
This study constructs a function-private inner-product predicate encryption(FP-IPPE)and achieves standard enhanced function privacy.The enhanced function privacy guarantees that a predicate secret key skf reveals noth... This study constructs a function-private inner-product predicate encryption(FP-IPPE)and achieves standard enhanced function privacy.The enhanced function privacy guarantees that a predicate secret key skf reveals nothing about the predicate f,as long as f is drawn from an evasive distribution with sufficient entropy.The proposed scheme extends the group-based public-key function-private predicate encryption(FP-PE)for“small superset predicates”proposed by Bartusek et al.(Asiacrypt 19),to the setting of inner-product predicates.This is the first construction of public-key FP-PE with enhanced function privacy security beyond the equality predicates,which is previously proposed by Boneh et al.(CRYPTO 13).The proposed construction relies on bilinear groups,and the security is proved in the generic bilinear group model. 展开更多
关键词 predicate encryption function privacy inner product generic group model
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Research on Denoising Method of Agricultural Product Terahertz Spectroscopy Based on Adaptive Signal Decomposition
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作者 WU Jing-zhu LIU Yu-hao +3 位作者 YANG Yi XIE Chuan-luan L Zhong-ming LI Yi-can 《光谱学与光谱分析》 北大核心 2025年第12期3575-3584,共10页
To address the issues of peak overlap caused by complex matrices in agricultural product terahertz(THz)spectral signals and the dynamic,nonlinear interference induced by environmental and system noise,this study explo... To address the issues of peak overlap caused by complex matrices in agricultural product terahertz(THz)spectral signals and the dynamic,nonlinear interference induced by environmental and system noise,this study explores the feasibility of adaptive-signal-decomposition-based denoising methods to improve THz spectral quality.THz time-domain spectroscopy(THz-TDS)combined with an attenuated total reflection(ATR)accessory was used to collect THz absorbance spectra from 48 peanut samples.Taking the quantitative prediction model of peanut moisture content based on THz-ATR as an example,wavelet transform(WT),empirical mode decomposition(EMD),local mean decomposition(LMD),and its improved methods-segmented local mean decomposition(SLMD)and piecewise mirror extension local mean decomposition(PME-LMD)-were employed for spectral denoising.The applicability of different denoising methods was evaluated using a support vector regression(SVR)model.Experimental results show that the peanut moisture content prediction model constructed after PME-LMD denoising achieved the best performance,with a root mean square error(RMSE),coefficient of determination(R^(2)),and mean absolute percentage error(MAPE)of 0.010,0.912,and 0.040,respectively.Compared with traditional methods,PME-LMD significantly improved spectral quality and model prediction performance.The PME-LMD denoising strategy proposed in this study effectively suppresses non-uniform noise interference in THz spectral signals,providing an efficient and accurate preprocessing method for THz spectral analysis of agricultural products.This research provides theoretical support and technical guidance for the application of THz technology for detecting agricultural product quality. 展开更多
关键词 Terahertz spectroscopy Denoising method Agricultural products Support vector regression Piecewise mirror extension local mean decomposition
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Call for Papers from Food Science of Animal Products
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《肉类研究》 北大核心 2025年第11期I0018-I0018,共1页
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food mater... Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects. 展开更多
关键词 animal origin foods EGGS animal offals food materials MEAT MILK food science animal products issn e issn edible insects
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Detonation product analysis and the paradoxical performance mechanism of TKX-50:High detonation velocity with low metal acceleration
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作者 Kaiyuan Tan Yaqi Zhao +10 位作者 Qin Liu Lixiao Hao Yushi Wen Chunliang Ji Sha Yang Haoxu Wang Luchuan Jia Jiahui Liu Zhuoping Duan Yong Han Fenglei Huang 《Defence Technology(防务技术)》 2025年第4期255-266,共12页
This study investigates the paradoxical detonation behavior of TKX-50,a nitrogen-rich energetic material,exhibiting higher detonation velocities but lower metal acceleration ability compared to HMX.Through experimenta... This study investigates the paradoxical detonation behavior of TKX-50,a nitrogen-rich energetic material,exhibiting higher detonation velocities but lower metal acceleration ability compared to HMX.Through experimental measurements and theoretical calculations,we propose a novel three-factor competition mechanism to explain this phenomenon.TKX-50-based PBX formulations achieved detonation velocities up to 9100 m/s,surpassing HMX-based counterparts.However,cylinder expansion tests revealed a 15%reduction in metal acceleration ability.Thermochemical measurements showed lower detonation heat for TKX-50(4900 J/g)versus HMX(5645 J/g).Our mechanism involves:(1)compositional effects prevailing at high pressures;(2)Energy release becoming essential as pressure drops;(3)Pressure-dependent product composition evolution functioning at low pressure.VLW code calculations unveiled a"crossover"in Hugoniot curves,lending support to this mechanism.This study furnishes a new framework for comprehending the performance of nitrogen-rich energetic materials,with significant implications for the design and optimization of future high-energy density materials. 展开更多
关键词 TKX-50 Nitrogen-rich explosives Detonation velocity Metal acceleration Detonation product
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Modeling and analysis of a novel oxygen production approach with full-spectrum solar energy for the lunar human base
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作者 Wei Zhu Maobin Hu 《中国科学技术大学学报》 北大核心 2025年第2期2-17,1,I0001,共18页
Building a lunar human base is one of the important goals of human lunar exploration.This paper proposes a method for the production of oxygen by combining photothermal synergistic water decomposition with high-temper... Building a lunar human base is one of the important goals of human lunar exploration.This paper proposes a method for the production of oxygen by combining photothermal synergistic water decomposition with high-temperature carbon dioxide electrolysis,utilizing the full solar spectrum.The optimal oxygen production rates under different solid oxide electrolysis cell inlet temperatures T_(e),ultraviolet(UV)separation wavelengths λ_(2),infrared(IR)separation wavelengths,and photovoltaic cell materials were explored.The results indicate that the inlet temperature of the solid oxide electrolysis cell should be as high as possible so that more carbon dioxide can be converted into carbon monoxide and oxygen.Furthermore,when the ultraviolet separation wavelength is approximately 385 nm,the proportion of solar energy allocated to the photoreaction and electrolysis cell is optimal,and the oxygen production rate is highest at 2.754×10^(-4) mol/s.Moreover,the infrared separation wavelength should be increased as much as possible within the allowable range to increase the amount of solar radiation allocated to the electrolysis cell to improve the rate of oxygen generation.In addition,copper indium gallium selenide(CIGS)has a relatively large separation wavelength,which can result in a high oxygen production rate of 3.560×10^(-4) mol/s.The proposed integrated oxygen production method can provide a feasible solution for supplying oxygen to a lunar human base. 展开更多
关键词 lunar oxygen production full-spectrum solar energy photovoltaic and photon-enhanced thermionic emission electrolysis of carbon dioxide photothermal synergistic reaction solid oxide electrolysis cell
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Call for Papers from Food Science of Animal Products
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《肉类研究》 北大核心 2025年第10期I0018-I0018,共1页
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food mater... Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects.The research scope includes the quality and processing characteristics of food raw materials,the relationships of nutritional components and bioactive substances with human health,product flavor and sensory characteristics,the control of harmful substances during processing or cooking,product preservation,storage and packaging;microorganisms and fermentation,illegal drug residues and food safety detection;authenticity identification;cell-cultured meat,regulations and standards. 展开更多
关键词 edible insectsthe animal origin foods food raw materialsthe nutritional components bioactive substances food materials food science animal products issn e issn quality processing characteristics
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Call for Papers from Food Science of Animal Products
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《食品科学》 北大核心 2025年第20期I0021-I0021,共1页
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food mater... Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects.The research scope includes the quality and processing characteristics of food raw materials,the relationships of nutritional components and bioactive substances with human health,product flavor and sensory characteristics,the control of harmful substances during processing or cooking,product preservation,storage and packaging;microorganisms and fermentation,illegal drug residues and food safety detection;authenticity identification;cell-cultured meat,regulations and standards. 展开更多
关键词 edible insectsthe animal origin foods food raw materialsthe nutritional components bioactive substances food materials food science animal products issn e issn quality processing characteristics
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Call for Papers from Food Science of Animal Products
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《食品科学》 北大核心 2025年第12期I0022-I0022,共1页
Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food mater... Food Science of Animal Products(ISSN:2958-4124,e-ISSN:2958-3780)is a peer-reviewed,open access international journal that publishes the latest research findings in the field of animal-origin foods,involving food materials such as meat,aquatic products,milk,eggs,animal offals and edible insects.The research scope includes the quality and processing characteristics of food raw materials,the relationships of nutritional components and bioactive substances with human health,product flavor and sensory characteristics,the control of harmful substances during processing or cooking,product preservation,storage and packaging;microorganisms and fermentation,illegal drug residues and food safety detection;authenticity identifi cation;cell-cultured meat,regulations and standards. 展开更多
关键词 edible insectsthe animal origin foods food raw materialsthe nutritional components bioactive substances food materials food science animal products issn e issn quality processing characteristics
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Experimental and numerical analysis of near-field detonation products and shock wave characteristics for cylindrical charge
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作者 Ruilong Ma Xinjie Wang +2 位作者 Sa You Zhimin Sun Fenglei Huang 《Defence Technology(防务技术)》 2025年第11期242-258,共17页
Predictions of extreme near-field blast wave for cylindrical charge is crucial for designing sympathetic detonation protection structures,yet the quantitative analysis of detonation products and shock wave field are s... Predictions of extreme near-field blast wave for cylindrical charge is crucial for designing sympathetic detonation protection structures,yet the quantitative analysis of detonation products and shock wave field are still insufficient.The present work conducted experiments and numerical simulations of nearfield explosion for kilogram scale cylindrical charge,and investigated the propagation and spatial distribution characteristics of incident and reflected blast waves.The results show that near-field reflected overpressure exhibits multi-peak structures,which are primarily governed by reflections of detonation products and shock wave.The reflected peak overpressure dominated by detonation products shows higher sensitivity to scaled distance.Meanwhile,the Rayleigh-Taylor instability(RTI)effect induces the evolutions of detonation products and shock wave interface from smooth to random microjets,increasing dispersion of secondary re flected peak overpressure.In free-field explosion,the incident peak overpressure exhibits a dual-peak structure,governed by the shock wave front and detonation products flowing past the gauge points.The incident peak overpressure dominated by detonation products is sensitive to orientations due to the charge structures.As the aspect ratio of charge increases from 0.6 to 8,the dominant radial azimuth angle region expands from 60°-90°to 30°-90°.An empirical model was developed to predict the spatial distributions of incident peak loads at arbitrary orientations for cylindrical charge with 0.6≤L/D≤8.0 and 0.06 m·kg^(-1/3) 展开更多
关键词 Near-field explosion Cylindrical charge Detonation products effect Peak loads spatial distribution Empirical predictive model
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Ei Village 2和Web of Knowledge数据库平台的比较分析 被引量:8
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作者 罗春荣 《图书馆论坛》 CSSCI 北大核心 2004年第2期82-86,共5页
以INSPEC数据库为例 ,比较和分析了EiVillage 2和WebofKnowledge在检索功能、检索结果的处理、整合功能、个性化服务、检索效率及管理功能等方面的异同 。
关键词 数据库检索 检索平台 Ei village 2 Web of Knowledge 检索功能 检索结果 个性化服务 检索效率
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Ei Village 与 Ei Village 2 比较分析 被引量:10
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作者 黄美君 杨毅 《大学图书馆学报》 CSSCI 北大核心 2002年第5期14-20,共7页
通过EiVillage与EiVillage2检索系统的比较,分析了它们在检索界面、收录文献量、检索功能、与电子版全文和OPAC的链接、个性化服务等方面的异同,提出了目前文献检索系统所存在的问题、改进的方法及今后的发展方向。
关键词 Eivillage Eivillage2 比较分析 工程索引 检索系统 检索功能 检索界面 收录文献量
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Ei Village 2的CAI课件的设计与制作
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作者 谢立虹 夏浩 《图书馆论坛》 CSSCI 北大核心 2004年第2期97-98,共2页
分析了EiVillage 2的主要特点 ,介绍用PowePoint制作EiVillage 2的CAI课件的内容要点、设计思路及实现方法。
关键词 Ei village 2 工程数据库 数据库检索 CAI课件 文献检索课 多媒体辅助教学
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EI Village2及论文投稿策略 被引量:2
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作者 陈吟月 《现代情报》 北大核心 2006年第2期216-217,220,共3页
EI Village2是工程技术最重要的数据库之一。文章主要介绍了EI Village2数据库概况、检索服务功能特色以及核心数据库Compendex的收录标准,探讨了科技论文被EI Village2收录的投稿选择。
关键词 EI village2 检索服务功能 投稿策略
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Ei Village及其核心数据库检索功能的新变化 被引量:1
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作者 徐家坤 《情报杂志》 CSSCI 北大核心 2003年第12期72-73,共2页
介绍了EiVillage主要服务功能及其核心数据库检索功能的新变化
关键词 Ei village “工程信息村” 工程信息资源 数据库 检索功能 工程信息服务
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