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Degradation properties of fulvic acid and its microbially driven mechanism from a partial nitritation bioreactor through multi-spectral and bioinformatic analysis

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Journal of Environmental Sciences 2024年第1期135卷 318-331页

作者： Quanhao Dou Li Zhang Tingjun Dong Zixuan Song Xuepeng Fan Yongzhen Peng Xiayan Wang jiachun yang National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery EngineeringBeijing University of TechnologyBeijing 100124China Department of Chemistry and Biology Center of Excellence for Environmental Safety and Biological EffectsBeijing Key Laboratory for Green Catalysis and SeparationBeijing University of TechnologyBeijing 100124China Environmental Protection Development Group Co. Ltd.Shandong 250101China

This study employed multispectral techniques to evaluate fulvic acid(FA)compositional characteristic and elucidate its biodegradation mechanisms during partial nitritation(PN)process.Results showed that FA removal efficiency(FRE)decreased from 90.22 to 23.11%when FA concentrations in the reactor were increased from 0 to 162.30 mg/L,and that molecular size,degree of aromatization and humification of the effluent FA macromolecules all increased after treatment.Microbial population analysis indicated that the proliferation of the Comamonas,OLB12 and Thauera exhibit high FA utilization capacity in lower concentrations(<50.59 mg/L),promoting the degradation and removal of macromolecular FA.In addition,the sustained increase in external FA may decrease the abundance of above functional microorganisms,resulting in a rapid drop in FRE.Furthermore,from the genetic perspective,the elevated FA levels restricted carbohydrate(ko00620,ko00010 and ko00020)and nitrogen(HAO,AMO,NIR and NOR)metabolism-related pathways,thereby impeding FA removal and total nitrogen loss associated with N_(2)O emissions.

关键词： Partial nitritation Fulvic acid 3DEEM-PARAFAC UV/Vis Microbially driven mechanism

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Periodic signal extraction of GNSS height time series based on adaptive singular spectrum analysis

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Geodesy and Geodynamics 2024年第1期15卷 50-60页

作者： Chenfeng Li Peibing yang Tengxu Zhang jiachun Guo Three Gorges Geotechnical Engineering Co.Ltd.(Wuhan) Wuhan 430074China College of Resources and Environmental Science and Engineering Hubei University of Science and TechnologyXian©ning 437100China College of Civil Engineering Anhui Jianzhu UniversityHefei 230601China

Singular spectrum analysis is widely used in geodetic time series analysis.However,when extracting time-varying periodic signals from a large number of Global Navigation Satellite System(GNSS)time series,the selection of appropriate embedding window size and principal components makes this method cumbersome and inefficient.To improve the efficiency and accuracy of singular spectrum analysis,this paper proposes an adaptive singular spectrum analysis method by combining spectrum analysis with a new trace matrix.The running time and correlation analysis indicate that the proposed method can adaptively set the embedding window size to extract the time-varying periodic signals from GNSS time series,and the extraction efficiency of a single time series is six times that of singular spectrum analysis.The method is also accurate and more suitable for time-varying periodic signal analysis of global GNSS sites.

关键词： GNSS Time series Singular spectrum analysis Trace matrix Periodic signal

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The variation in basal channels and basal melt rates of Pine Island Ice Shelf

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Acta Oceanologica Sinica 2024年第1期43卷 22-34页

作者： Mingliang Liu Zemin Wang Baojun Zhang Xiangyu Song jiachun An Chinese Antarctic Center of Surveying and Mapping Wuhan UniversityWuhan 430079China Key Laboratory of Polar Environment Monitoring and Public Governance(Wuhan University) Ministry of EducationWuhan 430079China School of Civil Engineering Shijiazhuang Tiedao UniversityShijiazhuang 050043China Key Laboratory of Roads and Railway Engineering Safety Control(Shijiazhuang Tiedao University) Ministry of EducationShijiazhuang 050043China

In recent years,there has been a significant acceleration in the thinning,calving and retreat of the Pine Island Ice Shelf(PIIS).The basal channels,results of enhanced basal melting,have the potential to significantly impact the stability of the PIIS.In this study,we used a variety of remote sensing data,including Landsat,REMA DEM,ICESat-1 and ICESat-2 satellite altimetry observations,and Ice Bridge airborne measurements,to study the spatiotemporal changes in the basal channels from 2003 to 2020 and basal melt rate from 2010 to 2017 of the PIIS under the Eulerian framework.We found that the basal channels are highly developed in the PIIS,with a total length exceeding 450 km.Most of the basal channels are ocean-sourced or groundingline-sourced basal channels,caused by the rapid melting under the ice shelf or near the groundingline.A raised seabed prevented warm water intrusion into the eastern branch of the PIIS,resulting in a lower basal melt rate in that area.In contrast,a deepsea trough facilitates warm seawater into the mainstream and the western branch of the PIIS,resulting in a higher basal melt rate in the main-stream,and the surface elevation changes above the basal channels of the mainstream and western branch are more significant.The El Ni?o event in 2015–2016 possibly slowed down the basal melting of the PIIS by modulating wind field,surface sea temperature and depth seawater temperature.Ocean and atmospheric changes were driven by El Ni?o,which can further explain and confirm the changes in the basal melting of the PIIS.

关键词： Pine Island Ice Shelf basal channel basal melt rate digital elevation models(DEMs) satellite altimetry

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Simulation Analysis of Torsion Beam Hydroforming Based on the Fluid-Solid Coupling Method

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Chinese Journal of Mechanical Engineering 2023年第1期36卷 139-156页

作者： Yu Huang Jian Li jiachun yang Yongdong Peng Weixuan Zhang Guangxi Key Laboratory of Automobile Components and Vehicle Technology Guangxi University of Science and TechnologyLiuzhou545006GuangxiChina

Hydroformed parts are widely used in industrial automotive parts because of their higher stiffness and fatigue strength and reduced weight relative to their corresponding cast and welded parts.This paper reports a hydraulicforming experimental platform for rectangular tube fittings that was constructed to conduct an experiment on the hydraulic forming of rectangular tube fittings.A finite element model was established on the basis of the fluid–solid coupling method and simulation analysis.The correctness of the simulation analysis and the feasibility of the fluid–solid coupling method for hydraulic forming simulation analysis were verified by comparing the experimental results with the simulation results.On the basis of the simulation analysis of the hydraulic process of the torsion beam using the fluid–solid coupling method,a sliding mold suitable for the hydroforming of torsion beams was designed for its structural characteristics.The effects of fluid characteristics,shaping pressure,axial feed rate,and friction coefficient on the wall thicknesses of torsions beams during formation were investigated.Fluid movement speed was related to tube deformation.Shaping pressure had a significant effect on rounded corners and straight edges.The axial feed speed was increased,and the uneven distribution of wall thicknesses was effectively improved.Although the friction coefficient had a nonsignificant effect on the wall thickness of the ladder-shaped region,it had a significant influence on a large deformation of wall thickness in the V-shaped area.In this paper,a method of fluid-solid coupling simulation analysis and sliding die is proposed to study the high pressure forming law in torsion beam.

关键词： Fluid-solid coupling Hydraulic expansion Rectangular tube Torsional beam Wall thickness distribution

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Genetic diversity of RNA viruses infecting invertebrate pests of rice

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Science China(Life Sciences) 2024年第1期67卷 175-187页

作者： Haoran Wang Shufen Chao Qing Yan Shu Zhang Guoqing Chen Chonghui Mao yang Hu Fengquan Yu Shuo Wang Liang Lv Baojun yang jiachun He Songbai Zhang Liangsheng Zhang Peter Simmonds Guozhong Feng State Key Laboratory of Rice Biology and Breeding China National Rice Research InstituteChinese Academy of Agricultural SciencesHangzhou 311400China State Key Laboratory of Agricultural Microbiology College of Life Science and TechnologyHuazhong Agricultural UniversityWuhan 430070China Institute of Plant Protection&Soil Fertilizer Hubei Academy of Agricultural SciencesWuhan 430064China Institute of Plant Protection Guizhou Academy of Agricultural SciencesGuiyang 550000China Institute of Plant Protection Liaoning Academy of Agricultural SciencesShenyang 110161China Sanya Agricultural Technology Extension and Service Centre Sanya 572000China College of Agriculture Yangtze UniversityJingzhou 434000China Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology Fujian Agriculture and Forestry UniversityFuzhou 350002China Genomics and Genetic Engineering Laboratory of Ornamental Plants College of Agriculture and BiotechnologyZhejiang UniversityHangzhou 310012China Nuffield Department of Medicine Peter Medawar Building for Pathogen ResearchUniversity of OxfordOxford OX13SYUnited Kingdom

Invertebrate species are a natural reservoir of viral genetic diversity,and invertebrate pests are widely distributed in crop fields.However,information on viruses infecting invertebrate pests of crops is limited.In this report,we describe the deep metatranscriptomic sequencing of 88 invertebrate samples covering all major invertebrate pests in rice fields.We identified 296 new RNA viruses and 13 known RNA viruses.These viruses clustered within 31 families,with many highly divergent viruses constituting potentially new families and genera.Of the identified viruses,13 RNA viruses clustered within the Fiersviridae family of bacteriophages,and 48 RNA viruses clustered within families and genera of mycoviruses.We detected known rice viruses in novel invertebrate hosts at high abundances.Furthermore,some novel RNA viruses have genome structures closely matching to known plant viruses and clustered within genera of several plant virus species.Fortyfive potential insect pathogenic RNA viruses were detected in invertebrate species.Our analysis revealed that host taxonomy plays a major role and geographical location plays an important role in structuring viral diversity.Cross-species transmission of RNA viruses was detected between invertebrate hosts.Newly identified viral genomes showed extensive variation for invertebrate viral families or genera.Together,the large-scale metatranscriptomic analysis greatly expands our understanding of RNA viruses in rice invertebrate species,the results provide valuable information for developing efficient strategies to manage insect pests and virus-mediated crop diseases.

关键词： invertebrate species metatranscriptome viral diversity viral transmission viral genomes

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Metagenomic insights into responses of microbial population and key functional genes to fulvic acid during partial nitritation

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Journal of Environmental Sciences 2023年第2期124卷 952-962页

作者： Li Zhang Shuang Lan Quanhao Dou Shiwei Hao Yueping Wang Xiaoxuan Wang Ruoyan Zhang Yongzhen Peng jiachun yang National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery EngineeringBeijing University of TechnologyBeijing 100124China Shuifa Shandong Water Development Group Co.Ltd. Shandong 274200China

The long-term impact of fulvic acid(FA)on partial nitritation(PN)systemwas initially examined in this study.The obtained results revealed that the FA lower than 50 mg/L had negligible effect on the nitrite accumulation rate(NAR nearly 100%)and ammonium removal rate(ARR 56.85%),while FA over 50 mg/L decreased ARR from 56.85%to 0.7%.Sludge characteristics analysis found that appropriate FA(<50 mg/L)exposure promoted the settling performance and granulation of PN sludge by removing Bacteroidetes and accumulating Chloroflexi.The analysis of metagenomics suggested that the presence of limited FA(0-50 mg/L)stimulated the generation of NADH,which favors the denitrification and nitrite reduction.The negative impact of FA on the PN system could be divided into two stages.Initially,limited FA(50-120 mg/L)was decomposed by Anaerolineae to stimulate the growth and propagation of heterotrophic bacteria(Thauera).Increasing heterotrophs competed with AOB(Nitrosomonas)for dissolved oxygen,causing AOB to be eliminated and ARR to declined.Subsequently,when FA dosage was over 120 mg/L,Anaerolineae were inhibited and heterotrophic bacteria reduced,resulting in the abundance of AOB recovered.Nevertheless,the ammonium transformation pathway was suppressed because genes amoABC and hao were obviously reduced,leading to the deterioration of reactor performance.Overall,these results provide theoretical guidance for the practical application of PN for the treatment of FA-containing sewage.

关键词： Partial nitritation Fulvic acid Microbial community Functional genes Metagenomic

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Contrasting response of rice rhizosphere microbiomes to in situ cadmium-contaminated soil remediation

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Soil Ecology Letters 2024年第2期6卷 149-162页

作者： Zhongyi Cheng Qinyu Han Yan He jiachun Shi Laosheng Wu Jianming Xu Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment Institute of Soil and Water Resources and Environmental ScienceCollege of Environmental and Resource SciencesZhejiang UniversityHangzhou310058China Key Laboratory of Environment Remediation and Ecological Health Ministry of EducationHangzhou310058China Department of Environmental Sciences University of CaliforniaRiversideCA92521USA

Changes in soil properties and microbial communities regulated rhizosphere protistan assemblages. • Bacterial community was more sensitive to soil amendments than protists and fungi. • Soil amendments trigger the role of specific protistan taxa Cercozoa on microbial interactions. Understanding the responses of different rhizosphere microbial lineages to soil amendments during in situ remediation of Cd-contaminated soil is of great importance in the assessment of the restoration and crop health. Here, we evaluated the effects of lime (LM), biochar (BC), pig manure (PM), and a commercial Mg-Ca-Si conditioner (CMC) on the rice rhizosphere soil physicochemical properties and community assembly of bacteria, fungi, and protists in a six-year consecutive application of soil amendments field trial. Our results indicated that among the four amendments, the BC and CMC had the best efficiency in increasing soil pH, which were 5.2% and 16.2%, respectively. Despite the differences in soil Cd concentrations is not noticeable, all the soil amendment treatments significantly decreased the proportion of available Cd in total Cd compared to the control. Soil amendments significantly altered the diversity of bacterial community, while they had no effect on fungal and protistan communities. Linear discriminant analysis effect size (LEfSe) showed that the bacteria was more sensitive to soil amendment-induced changes. For protists, treatments with LM and BC changed the groups of protistan consumers, while treatments with PM and CMC significantly increased the relative abundances of protistan phototrophs. Co-occurrence network analysis revealed that soil amendments increased microbial network complexity and triggered the role of protists, especially for the predatory protists Cercozoa, on microbial trophic interactions. Further variation partitioning analysis revealed that edaphic properties, bacterial and fungal communities compositions together explained the 77% of the total variation in protistan community, and the stronger correlat

关键词： cadmium soil amendments soil protist community microbial interactions

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Gelatin-Based Metamaterial Hydrogel Films with High Conformality for Ultra-Soft Tissue Monitoring

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Nano-Micro Letters 2024年第2期16卷 347-364页

作者： Yuewei Chen Yanyan Zhou Zihe Hu Weiying Lu Zhuang Li Ning Gao Nian Liu Yuanrong Li Jing He Qing Gao Zhijian Xie jiachun Li Yong He State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China School of Mechanical Engineering Guizhou UniversityGuiyang 550025People’s Republic of China Stomatology Hospital School of StomatologyZhejiang University School of MedicineClinical Research Center for Oral Diseases of Zhejiang ProvinceKey Laboratory of Oral Biomedical Research of Zhejiang ProvinceCancer Center of Zhejiang UniversityHangzhou 310006People’s Republic of China

Implantable hydrogel-based bioelectronics(IHB)can precisely monitor human health and diagnose diseases.However,achieving biodegradability,biocompatibility,and high conformality with soft tissues poses significant challenges for IHB.Gelatin is the most suitable candidate for IHB since it is a collagen hydrolysate and a substantial part of the extracellular matrix found naturally in most tissues.This study used 3D printing ultrafine fiber networks with metamaterial design to embed into ultra-low elastic modulus hydrogel to create a novel gelatin-based conductive film(GCF)with mechanical programmability.The regulation of GCF nearly covers soft tissue mechanics,an elastic modulus from 20 to 420 kPa,and a Poisson’s ratio from-0.25 to 0.52.The negative Poisson’s ratio promotes conformality with soft tissues to improve the efficiency of biological interfaces.The GCF can monitor heartbeat signals and respiratory rate by determining cardiac deformation due to its high conformability.Notably,the gelatin characteristics of the biodegradable GCF enable the sensor to monitor and support tissue restoration.The GCF metamaterial design offers a unique idea for bioelectronics to develop implantable sensors that integrate monitoring and tissue repair and a customized method for endowing implanted sensors to be highly conformal with soft tissues.

关键词： Implantable hydrogel-based bioelectronics Conformality 3D printing Metamaterial design

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集成视觉显著性和群决策的航空零件孔特征检测

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光学精密工程 2024年第1期32卷 125-136页

作者：田佳淳王亮梅标朱伟东浙江大学工程师学院浙江杭州310015 中航西安飞机工业集团股份有限公司陕西西安710089 中国科学院福建物质结构研究所泉州装备制造研究中心福建泉州362100 浙江大学机械工程学院浙江杭州310058

为了实现复杂环境下航空零件孔特征的高效高精度检测,提出了一种集成视觉显著性和群决策的检测方法。在经典FT显著性检测算法中引入图像增强步骤,并为每个像素赋予以最大显著区域中心为参考的权重,使用改进后的方法对图像进行孔区域分... 详细信息

为了实现复杂环境下航空零件孔特征的高效高精度检测,提出了一种集成视觉显著性和群决策的检测方法。在经典FT显著性检测算法中引入图像增强步骤,并为每个像素赋予以最大显著区域中心为参考的权重,使用改进后的方法对图像进行孔区域分割。设计具有多尺度多结构元素的新型数学形态学边缘检测算法,结合轮廓细化算法对孔区域进行轮廓提取。最后,利用Meanshift算法寻找轮廓点的圆心位置,建立新的基于群决策的圆半径计算模型,获得孔特征的关键几何参数。结果表明:改进的视觉显著性特征检测算法能够生成更加突显孔特征的全分辨率显著图;新型数学形态学边缘检测算法能获得简化且可靠的轮廓点;该方法在不均匀光照、各类孔缺陷和孔内壁干扰等条件下均显示出较好的稳定性;即使在噪声密度高达30%时仍能成功完成孔检测,且圆心坐标和半径的误差均小于0.012 mm;平均检测时间仅为0.236 s。该方法能够在复杂环境下对航空零件孔特征进行准确、稳定的检测。

关键词：航空零件孔特征检测显著性检测数学形态学群决策

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基于双目结构光的三维立体电路板焊点定位

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北京理工大学学报 2024年第6期44卷 615-624页

作者：刘少丽黄嘉淳杜浩浩邓超北京理工大学机械与车辆学院北京100081 北京理工大学唐山研究院河北唐山063000 中国电子科技集团公司第二十九研究所四川成都610036

三维立体电路将传统二维集成电路拓展至三维,在提高了电路板形状设计柔性的同时,也提升了电路板上元器件焊点定位的复杂度.为了降低三维立体电路加工过程中的人力成本,提高加工效率,设计了一种用于焊接机床对三维立体电路板焊点定位的... 详细信息

三维立体电路将传统二维集成电路拓展至三维,在提高了电路板形状设计柔性的同时,也提升了电路板上元器件焊点定位的复杂度.为了降低三维立体电路加工过程中的人力成本,提高加工效率,设计了一种用于焊接机床对三维立体电路板焊点定位的双目结构光系统,并针对双目结构光系统在与焊接机床结合应用过程中存在的坐标转换、焊点识别困难等问题,从硬件与算法层面提出了解决方案.在软硬件的配合下,可以简单快速地完成双目结构光系统与焊接机床之间的坐标转换,并对电路板焊点完成定位与坐标计算,代替了人工对三维立体电路板焊点测量定位的复杂流程.实验表明,提出的方案具有较高的精度,能够满足机床焊接元器件过程中对焊点的定位需求.

关键词：三维立体电路双目结构光焊接机床坐标转换焊点定位

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