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海洋开发与管理 2021年第2期38卷 81-86页

作者：黄路冯旭文乔正明杨星晨邵浩吴春芳国家海洋技术中心漳州基地筹建办公室厦门361007 自然资源部第二海洋研究所杭州310012 91039部队北京102401

计量检定和海上标校试验是目前船载观测设备在室内和室外开展测量精度评价的2种常用手段。为进一步推进我国计量检定和海上试验建设发展,文章系统归纳和总结室内计量检定和海上标校试验的原理、特点和工作现状,分析当前各自存在的问题,... 详细信息

计量检定和海上标校试验是目前船载观测设备在室内和室外开展测量精度评价的2种常用手段。为进一步推进我国计量检定和海上试验建设发展,文章系统归纳和总结室内计量检定和海上标校试验的原理、特点和工作现状,分析当前各自存在的问题,并提出具体建议。研究结果表明:军、地对于船载观测设备计量检定和海上标校试验的需求越来越迫切,我国虽已基本建成海洋设备计量技术规范体系,并强化海试全过程的质量控制,但仍存在计量标准、评价体系、维修保障和室外检定手段不足,海上试验环境和比测精度不确定以及缺少标准化海上试验设施和平台等问题;计量检定机构应综合分析计量要素的特点、社会效益和难易程度等,研究并制定行之有效的标准规范和保障措施;还应充分发挥海上试验的综合检验评价功能,研究完善比测校准方法,建设标准化的海上试验设施和平台。

关键词：计量检定海上标校试验船载观测设备测量精度评价校准方法

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Phytoplankton community changes in a coastal upwelling system during the last century

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Global and Planetary Change 2023年 224卷

作者： Peng, Peng Bi, Rong Sachs, Julian P. Shi, Jie Luo, Yifei Chen, Weifang Huh, Chih-An Yu, Meng Cao, Yali Wang, Yaoyao Cao, Zhong Bao, Xiaohan Guo, Xinyu Li, Huijuan feng, xuwen Li, Hongchun Zhao, Meixun Frontiers Science Center for Deep Ocean Multispheres and Earth System and Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education Ocean University of China Qingdao266100 China Laoshan Laboratory Qingdao266237 China School of Oceanography University of Washington Box 355351 SeattleWA98195 United States Key laboratory of Marine Environment and Ecology Ministry of Education Ocean University of China Qingdao266100 China State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences Xiamen University Xiamen361102 China Institute of Earth Sciences Academia Sinica Taipei11529 Taiwan Yantai Maritime Safety Administration Yantai264000 China Jinan250014 China Second Institute of Oceanography Ministry of Natural Resources of People's Republic of China Hangzhou310012 China Department of Geosciences National Taiwan University Taipei10617 Taiwan

Phytoplankton communities in coastal upwelling systems are influenced by the interplay between human-induced and natural climate forcing that vary regionally and the two factors have not been well quantified. Combining lipid biomarker analyses in 23 sediment cores from the Zhejiang coast of the East China Sea and a physical-ecological model, we found that during the 1960s–2000s there was a 42 ± 4% increase in diatom proportions and a 17 ± 8% decrease in dinoflagellate proportions within the core upwelling area that is attributed to changes in Kuroshio Current transport and coastal upwelling. During the 1950s–2000s there was a 16 ± 8% increase in dinoflagellate proportions and 12 ± 4% decrease in diatom proportions outside the core upwelling area which is attributed to anthropogenic nutrient inputs and climate warming. Our results provide a novel approach to quantify mechanisms of past and future changes in marine phytoplankton communities. © 2023 Elsevier B.V.

关键词： Ocean currents

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低产老化虾池的生态养殖的探讨

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湛江海洋大学学报 1999年第2期19卷 9-13页

作者：胡贤德苏强华冯伍湛江海洋大学科研处湛江524088 徐闻县迈陈对虾养殖塘

针对目前大批低产老化虾池的改造和可持续生产的问题，设计了一个自然生态养虾新模式。利用长期不能清淤的低产老化虾池和已造成生态失衡的虾池，实行疏放苗，精管理，综合利用、立体开发，混养、轮养。试验结果表明，养殖周期为８０... 详细信息

针对目前大批低产老化虾池的改造和可持续生产的问题，设计了一个自然生态养虾新模式。利用长期不能清淤的低产老化虾池和已造成生态失衡的虾池，实行疏放苗，精管理，综合利用、立体开发，混养、轮养。试验结果表明，养殖周期为８０～９０ｄ，对虾成活率６０．５％～７６％，体长达１０．１～１３．２ｃｍ，平均体重１７．２～１９．２ｇ／尾，饵料系数０．７７～０．８０，平均产量６４５～７８０ｋｇ／ｈｍ２，鲻鱼产量４２０～４６５ｋｇ／ｈｍ２。整个养殖过程虾池的各种水质理化因子基本符合要求。

关键词：斑节对虾低产老化虾池生态养殖

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A comprehensive analysis of the microbial diversity in natural and engineered ecosystems based on high-throughput sequencing of 16S rRNA gene

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INTERNATIONAL BIODETERIORATION & BIODEGRADATION 2019年 140卷 160-168页

作者： Xia, Yu He, xuwen feng, Zeshen Zhang, Qing Yang, Hongying China Univ Min & Technol Beijing Sch Chem & Environm Engn Beijing 100083 Peoples R China Northeastern Univ Sch Met Shenyang 110819 Liaoning Peoples R China

Understanding microbial diversity across different ecosystems is important for discerning the mechanisms shaping the microbial community assembly. However, knowledge on differentiations of microbial diversity in various habitats especially engineered systems remains very limited. A comprehensive comparison of microbial diversity across natural and engineered environments, namely heavy metal polluted farm soil, forest, wastewater treatment plants (WWTPs), anaerobic digesters (ADs) and the Caspian Sea sediments, was made base on a collection of 115 samples from seven published 16S rRNA gene datasets generated by high-throughput sequencing. In each sample, 16,590 and 19,771 qualified sequences were detected, and they were classified into 615 to 3,162 operational taxonomic units (OTUs). The microbial communities in the engineered systems especially the AD showed relatively low alpha taxonomic and phylogenetic diversity. A total of 49 genera were present in more than 80% of the samples, accounting for 6.0% in population number and 25.6% in relative abundance (RA). The average abundance-weighted rRNA operon copy number of the communities from ADs and a food wastewater treatment plant (FW) was higher than that of others, suggesting that high loading rate of pollutants in ADs and FW resulted in relatively high abundance of r-strategists. Among 104 typical human bacterial pathogens (HBPs), 2 to 25 HBPs were detected in each sample, accounting for 0.05%-21.34% in RA. Mycobacterium phlei was widely present in 111 samples with an average RA of 0.12%. The number and RA of all the HBPs in each sample did not show an obvious ecosystem type related pattern. Results of detrended correspondence analysis (DCA) and cluster analysis showed that the microbial communities clustered based on habitat types. The communities of WWTPs and soil were very similar, falling into one cluster. For any two communities from the datasets, 75.6% of their beta nearest taxon index (beta NTI) values were h

关键词： Microbial community Natural environments Engineered systems Diversity Environmental conditions High-throughput sequencing

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Adsorption of PAHs on the Sediments from the Yellow River Delta as a Function of Particle Size and Salinity

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SOIL & SEDIMENT CONTAMINATION 2015年第2期24卷 103-115页

作者： Wang, Jianbing Wang, Can Huang, Qiuying Ding, feng He, xuwen China Univ Min & Technol Sch Chem & Environm Engn Beijing 100083 Peoples R China Henan Polytech Inst Dept Chem Engn Nanyang Peoples R China Minist Environm Protect Appraisal Ctr Environm & Engn Beijing Peoples R China

In a seawater environment, the particle size of sediment and salinity play an important role in the adsorption behaviors of polycyclic aromatic hydrocarbons (PAHs) on sediment. In this study, batch adsorption experiments were carried out with the sediments from the Yellow River Delta (YRD) to explore the effect of particle size and salinity on the adsorption behaviors of phenanthrene (Phe), fluoranthene (Fla), and pyrene (Pyr). Adsorption isotherms of PAHs on different-sized sediments can be described by a Freundlich model with the correlation coefficients ranging from 0.96 to 0.99. The adsorption capacity of PAHs was in reverse proportion to the particle size of the sediments and in direct proportion to salinity. The sediments with smaller particle size possessed higher content of aromatic and fat components, which had strong adsorption capacity toward PAHs. Salinity influenced the adsorption behaviors of PAHs by changing the solubility of PAHs and the physicochemical properties of the sediments. The salting-out constants of Phe, Fla, and Pyr were in the range of 0.292 to 0.296, 0.230 to 0.289, and 0.293 to 0.307 l/mol, respectively. These research findings are of importance to an assessment of the fate and transport of PAHs in seawater-sediment systems.

关键词： fate and transport fluoranthene pyrene Phenanthrene

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数字化视角下应急测绘管理服务平台的研究与设计

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测绘与空间地理信息 2025年第3期48卷 41-43页

作者：马旭文万术海唐伟王沛冯思园浙江省测绘科学技术研究院浙江杭州311100

为了高效应对重大突发事件和维护人民生命财产安全情景下的数字化管理的深度应用,通过相关文献资料的研究,并结合浙江省应急测绘管理工作的实际需求,提出一种面向突发事件全闭环管理的应急测绘管理服务平台的设计方案。系统阐述了平台... 详细信息

为了高效应对重大突发事件和维护人民生命财产安全情景下的数字化管理的深度应用,通过相关文献资料的研究,并结合浙江省应急测绘管理工作的实际需求,提出一种面向突发事件全闭环管理的应急测绘管理服务平台的设计方案。系统阐述了平台的业务流程、总体框架、功能模块和关键技术。该平台有效提升了应急测绘灾前、灾中、灾后的管理水平和工作效率,实现了事前防范准备、事发监测预警、事中处置救援、事后应急复盘的全流程管理。

关键词：数字化应急测绘管理闭环平台

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ISAR Imaging Based on Block Sparse Smoothed L0 Norm Recovery Algorithm 2

ISAR Imaging Based on Block Sparse Smoothed L0 Norm Recovery...

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2019 2nd International Conference on Advanced Algorithms and Control Engineering, ICAACE 2019

作者： feng, Junjie Zhang, xuwen Wang, Yonghui School of Electrical Engineering Liupanshui Normal University Liupanshui GUIZHOU553004 China College of Electronic and Information Engineering Nanjing University of Aeronautics and Astronautics Nanjing211106 China

In order to obtain high resolution inverse synthetic aperture radar (ISAR) sparse images, a block sparse signal recovery ISAR imaging algorithm is proposed by considering the cluster characteristics of target in this paper. Firstly, the ISAR sparse imaging model is established, the imaging is converted to L0 norm optimization problem. Secondly, one negative exponential function sequence is used as smoothed function to approach the block L0 norm. Finally, the revised step is added to ensure solving the optimization problem along the steepest descent gradient direction and the cost function is updated for the next loop. Simulation results verify the proposed algorithm is effective. © Published under licence by IOP Publishing Ltd.

关键词： Inverse synthetic aperture radar

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Recent advances in the synthesis of biodegradable polyesters by sustainable polymerization: lipase-catalyzed polymerization

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RSC ADVANCES 2020年第59期10卷 36230-36240页

作者： Liu, Ying Song, Lijie feng, Na Jiang, Wei Jin, Yongri Li, xuwen Jilin Univ Coll Chem 2699 Qianjin Rd Changchun 130012 Jilin Peoples R China Jilin Prov Acad Tradit Chinese Med Clin Hosp 1 Changchun 130021 Peoples R China Zhengzhou Univ Acad Med Sci Dept Mol Pathol Applicat Ctr Precis MedAffiliated Hosp 2 Zhengzhou 450052 Henan Peoples R China

Over the past three decades, enzymatic polymerization has dramatically developed and gradually broadened as a creative methodology in the construction of polymeric materials with tailor-made structures and properties. Compared with transition metal catalyst polymerizations, enzymatic polymerization is more attractive in the biomedicine field due to the metal-free residue, good biocompatibility, and few by-products. Meanwhile, enzymatic polymerization has far more activity towards macrolides. In this review, the synthesis of lipase-catalyzed polymer materials is systematically summarized, focusing on the synthesis of the complex and well-defined polymers. The enzymatic polyester synthesis was then discussed concerning the different reaction types, including ring-opening polymerization, polycondensation, a combination of ring-opening polymerization with polycondensation, and chemoenzymatic polymerization. Besides, exploration of novel biocatalysts and reaction media was also described, with particular emphasis on the enzymes obtainedviaimmobilization or protein engineering strategies, green solvents, and reactors. Finally, recent developments in catalytic kinetics and mechanistic studies through the use of spectroscopy, mathematics, and computer techniques have been introduced. Besides, we addressed the remaining central issues in enzymatic polymerization and discussed current studies aimed at providing answers.

关键词： Ring opening polymerization

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Zeolite biofilm aeration filter plays a pre-nitritation role in autotrophic nitrogen removal from iron oxide red wastewater

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JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY 2020年第12期95卷 3261-3269页

作者： feng, Xinghui Wang, Xiaojun Wang, Ruixin Zheng, xuwen Zhong, Zhong Chen, Xiaozhen South China Univ Technol Sch Environm & Energy Guangzhou Peoples R China Minist Educ Key Lab Pollut Control & Ecosyst Restorat Ind Clu Guangzhou Peoples R China Hua An Biotech Co Ltd Foshan Peoples R China

BACKGROUND The completely autotrophic nitrogen removal over nitrite (CANON) system has excellent performance in treating ammonium-rich wastewater and it depends on ammonia oxidizing bacteria (AOB) working together with anammox bacteria in a reactor. Higher ammonium nitrogen loading requires higher aeration to provide sufficient dissolved oxygen (DO) for nitritation, whereas high-strength aeration in theCANON will destroy the sludge structure and inhibit the activity of anammox bacteria. The present study uses a stable pre-nitritation system to reduce a part of nitritation and also decrease aeration intensity in the CANON. RESULTS Continuous aeration to maintain the DO concentration between 1.5 and 4.3 mg L(-1)in the CANON achieved a stable nitrogen removal rate (1.22 kg N m(-3)d(-1)) from iron oxide red wastewater with 400-1016 mg N L(-1)after 183 days of operation. Using a mixed alkalinity donor [sodium carbonate (Na2CO3) and bicarbonate (NaHCO3)] in the combined system can save approximate to 14.1-28.2% of the alkalinity cost compared with using NaHCO(3)only. CONCLUSIONS A zeolite biofilm aeration filter (ZBAF) used in a pre-nitritation process can tolerate high DO concentration of <= 6.5 mg L(-1)for nitritation and avoid all of the nitritation taking place in the CANON system. This can protect the sludge structure and anammox bacteria from high-strength aeration erosion. (c) 2020 Society of Chemical Industry

关键词： pre-nitritation zeolite dissolved oxygen control Anammox granular sludge

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Dynamic design method of digital twin process model driven by knowledge-evolution machining features

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INTERNATIONAL JOURNAL OF PRODUCTION RESEARCH 2022年第7期60卷 2312-2330页

作者： Liu, Jinfeng Zhao, Peng Jing, xuwen Cao, Xuwu Sheng, Sushan Zhou, Honggen Liu, Xiaojun feng, feng Jiangsu Univ Sci & Technol Sch Mech Engn Zhenjiang 212003 Jiangsu Peoples R China Southeast Univ Sch Mech Engn Nanjing Peoples R China Shaanxi Diesel Engine Heavy Ind Co Ltd Xingping Peoples R China

Machining plan is the core of guiding manufacturing production and is regarded as one of the keys to ensure the quality of product processing. Existing process design methods are inefficient to quickly handle the machining plan changed induced by the unpredictable events in real-time production. It inevitably causes time and economic losses for the enterprise. In order to express the evolutionary characteristics of product processing, the construction method of digital twin process model (DTPM) is proposed based on the knowledge-evolution machining features. Three key technologies include correlation structure of process knowledge, expression method of the evolution geometric features and the association mechanism between two are solved. On this basis, the construction framework of DTPM is illustrated. Then, the organisation and management mechanism of multi-source heterogeneous data is discussed in detail. At last, a case study of the complex machined part is researched, the results show that the processing time reduced by about 7% and the processing stability improved by 40%. Meanwhile, the implementation scheme, application process and effect of this case are described in detail to provide reference for enterprises.

关键词： Digital twin process knowledge machining features dynamic evolution

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