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Effects of different carbon sources on the removal of ciprofloxacin and pollutants by activated sludge:Mechanism and biodegradation

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Journal of Environmental Sciences 2022年第1期34卷 240-248页

作者： Yixiang Cai Zhiyong Yan Yingjuan Ou Boshang Peng Lihua Zhang Jihai Shao Yiqing Lin jiachao Zhang Hunan International Scientific and Technological Cooperation Base of Agricultural Typical Pollution Remediation and Wetland Protection Hunan Agricultural UniversityChangsha 410028China

This research investigated the effects of ciprofloxacin(CIP)(0.5,5,and 20 mg/L)on SBR systems under different carbon source conditions.Microbial community abundance and structure were determined by quantitative PCR and high-throughput sequencing,respectively.The biodegradation production of CIP and possible degradation mechanism were also studied.Results showed that CIP had adverse effects on the nutrient removal from wastewater.Compared with sodium acetate,glucose could be more effectively used by microorganisms,thus eliminating the negative effects of CIP.Glucose stimulated the microbial abundance and increased the removal rate of CIP by 18%–24%.The mechanism research indicated that Proteobacteria and Acidobacteria had a high tolerance for CIP.With sodium acetate as a carbon source,the abundance of nitrite-oxidizing bacterial communities decreased under CIP,resulting in the accumulation of nitrite and nitrate.Rhodanobacter and Microbacterium played a major role in nitrification and denitrification when using sodium acetate and glucose as carbon sources.Dyella and Microbacterium played positive roles in the degradation process of CIP and eliminated the negative effect of CIP on SBR,which was consistent with the improved removal efficiency of pollutants.

关键词： Ciprofloxacin Microbial community Sequencing batch reactor Carbon source Biodegradation pathway

Influence of disturbance degree on the propped excavation stability in sandy soil in Shenyang,China

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Underground Space 2023年第3期10卷 150-165页

作者： jiachao Dong Chen Chen Manman Dong Bo Lu Yongping Guan Wen Zhao School of Resources and Civil Engineering Northeastern UniversityShenyang 110819China Northeast Architectural Design&Research Institute Co.Ltd Shenyang 110003China Department of Engineering Management Changshu Institute of TechnologyChangshu 215500China Taizhou Transportation Investment Group Taizhou 318000China

The stability of deep excavation is often investigated through numerical simulation.However,most constitutive models cannot take into account the influence of disturbance on soil response,especially for excavations in sandy soils.In this study,the conventional Dun-can–Chang constitutive model is modified based on the data obtained from a series of triaxial consolidated drained tests on medium coarse sand with different relative densities,where all input parameters in the model are correlated with the changes in relative density due to disturbance.The modified hyperbolic model is then implemented in the general-purpose finite element code,ABAQUS.The effi-ciency of the proposed constitutive mode is demonstrated by comparing with the experimental data.Furthermore,a case study of a large-scale propped excavation for a subway station in Shenyang is analyzed through numerical calculations with the conventional Mohr–Cou-lomb model and the proposed hyperbolic model,and theoretical derivations based on the current technical code in China.It is found that the proposed approach can provide reasonable estimations compared with field measurements with a maximum error of 28%for max-imum horizontal displacement of the solider pile and of 8%for maximum ground surface settlement,whereas the other techniques over-estimate the behaviour of deep excavation significantly by more than 90%.

关键词： Propped excavation Triaxial tests Constitutive model Disturbance degree Numerical analysis

A downshifting Eu^3+doped glass embedded with concave pyramid microstructure to improve the efficiency of silicon solar cell

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Journal of Rare Earths 2020年第11期38卷 1158-1164,I0001页

作者： Xing yang jiachao Chen Songsheng Zheng Chao Chen College of Energy Xiamen UniversityXiamen 361005China

The average photoelectric conversion efficiency(PCE)of a bare mono crystalline silicon solar cell is 14.71%±0.03%under AM1.5.It decreases to 14.20%±0.005%when covering an un-doped flat glass on the solar cell,and it goes down to 14.10%±0.005%by using a 5 wt%Eu^3+doped glass.The absorptions of the Eu^3+doped CPM glass one-to-one match the excitation spectra at 362,381,393,400,413 and464 nm,which are related to the transitions of 7 F0→(5 D4,5 G2,5 L6,5 D3),7 F1→5 D3,and 7 F0→5 D2,respectively.In addition,a concave pyramid microstructure(CPM)is embedded in the glass surface to increase light transmittance.The average PCE increases to 14.61%±0.07%when a 5 wt%Eu^3+doped CPM glass covers on the silicon solar cell.Compared with the un-doped flat glass,a net increase of the PCE is0.41%,where the 0.16%increment of PCE is from the lighting trapping of the CPM structure,and the downshifting of near ultraviolet(NUV)light by Eu^3+ion donates the other 0.25%increment.It confirms that the as-prepared Eu^3+doped CPM glass has a good downshifting and antireflection function.

关键词： Solar cell Concave pyramid microstructure Eu^3+doped glass Photoelectric conversion efficiency Rare earths

Responses of ammonia-oxidizing microorganisms to biochar and compost amendments of heavy metals-polluted soil

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Journal of Environmental Sciences 2021年第4期33卷 263-272页

作者： Mingyue Li jiachao Zhang Xiao yang Yaoyu Zhou Lihua Zhang Yuan yang Lin Luo Qingyun Yan College of Resources and Environment Hunan Agricultural UniversityChangsha 410128China Environmental Microbiomics Research Center School of Environmental Science and EngineeringSouthern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Sun Yat-sen UniversityGuangzhou 510006China Korea Biochar Research Center O-Jeong Eco-Resilience Institute(OJERI)&Division of Environmental Science and Ecological EngineeringKorea UniversitySeoul 02841Republic of Korea

Heavy metal pollution affects soil ecological function.Biochar and compost can effectively remediate heavy metals and increase soil nutrients.The effects and mechanisms of biochar and compost amendments on soil nitrogen cycle function in heavy-metal contaminated soils are not fully understood.This study examined how biochar,compost,and their integrated use affected ammonia-oxidizing microorganisms in heavy metal polluted soil.Quantitative PCR was used to determine the abundance of ammonia-oxidizing archaea(AOA)and bacteria(AOB).Ammonia monooxygenase(AMO)activity was evaluated by the enzymelinked immunosorbent assay.Results showed that compost rather than biochar improved nitrogen conversion in soil.Biochar,compost,or their integrated application significantly reduced the effective Zn and Cd speciation.Adding compost obviously increased As and Cu effective speciation,bacterial 16 S rRNA abundance,and AMO activity.AOB,stimulated by compost addition,was significantly more abundant than AOA throughout remediation.Correlation analysis showed that AOB abundance positively correlated with NO_(3)^(-)-N(r=0.830,P<0.01),and that AMO activity had significant correlation with EC(r=-0.908,P<0.01)and water-soluble carbon(r=-0.868,P<0.01).Those seem to be the most vital factors affecting AOB community and their function in heavy metal-polluted soil remediated by biochar and compost.

关键词： Biochar Compost Heavy metal Ammonia-oxidizing community Ammonia monooxygenase activity

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基于分离-重构技术的6R机器人逆解新方法

湖南工业大学学报 2021年第2期35卷 38-45页

作者：于权伟李光肖帆杨加超谢楚政湖南工业大学机械工程学院湖南株洲412007

提出一种利用分离-重构技术求6R机器人逆解的新方法。首先利用螺旋理论对机器人进行正向运动学建模,然后利用指数积公式的变换,证明了n自由度机器人的可分离性,以及重构连接的通用几何约束;最后以PUMA-560机器人为例,给出其分离及重新... 详细信息

提出一种利用分离-重构技术求6R机器人逆解的新方法。首先利用螺旋理论对机器人进行正向运动学建模,然后利用指数积公式的变换,证明了n自由度机器人的可分离性,以及重构连接的通用几何约束;最后以PUMA-560机器人为例,给出其分离及重新连接的几何约束条件。在满足约束条件的前提下,推导出各个关节角求解公式,最终求得机器人逆运动学解,且实际位姿与目标位姿误差数量级为10-13。所提出的新算法与D-H坐标法相比,计算速度提高了12%,且可避免奇异点的影响。

关键词：螺旋理论分离-重构逆运动学 PUMA-560机器人

Core processing neuron-enabled circuit motifs for neuromorphic computing

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InfoMat 2023年第11期5卷 78-88页

作者： Hanxi Li Jiayang Hu Anzhe Chen Yishu Zhang Chenhao Wang Beiduo Wang Yi Tong jiachao Zhou Kian Ping Loh yang Xu Tawfique Hasan Bin Yu School of Micro-Nano Electronics Zhejiang UniversityHangzhouthe People's Republic of China ZJU-Hangzhou Global Scientific and Technological Innovation Center Hangzhouthe People's Republic of China School of Materials Science and Engineering Zhejiang UniversityHangzhouthe People's Republic of China Department of Polymer Science and Engineering Zhejiang UniversityHangzhouthe People's Republic of China Gusu Laboratory of Materials Suzhouthe People's Republic of China Department of Chemistry National University of SingaporeSingaporeSingapore Joint Institute of Zhejiang University and the University of Illinois at Urbana-Champaign Zhejiang UniversityHainingthe People's Republic of China Cambridge Graphene Centre Cambridge University Engineering DepartmentCambridgeUK

Based on brain-inspired computing frameworks,neuromorphic systems implement large-scale neural networks in hardware.Although rapid advances have been made in the development of artificial neurons and synapses in recent years,further research is beyond these individual components and focuses on neuronal circuit motifs with specialized excitatory-inhibitory(E-I)connectivity patterns.In this study,we demonstrate a core processor that can be used to construct commonly used neuronal circuits.The neuron,featuring an ultracompact physical configuration,integrates a volatile threshold switch with a gate-modulated two-dimensional(2D)MoS_(2) field-effect channel to process complex E-I spatiotemporal spiking signals.Consequently,basic neuronal circuits are constructed for biorealistic neuromorphic computing.For practical applications,an algorithm-hardware co-design is implemented in a gatecontrolled spiking neural network with substantial performance improvement in human speech separation.

关键词： artificial intelligence hardware excitatory-inhibitory neurons neuronal circuit motifs speech separation spiking neural networks

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地下工程咬合型管幕构件抗弯承载力研究

建筑结构 2024年第6期54卷 38-45,17页

作者：李伟伟董驾潮金文强赵文刘玉平关永平广州地铁设计研究院股份有限公司广州510010 东北大学资源与土木工程学院沈阳110819 沈阳建筑大学交通工程学院沈阳110168

基于咬合型管幕试件的抗弯性能试验,研究了咬合型管幕试件的力学性能及破坏形态。为进一步研究关键结构参数对咬合型管幕试件抗弯性能的影响,运用ABAQUS建立了咬合型管幕试件的有限元模型,并通过室内试验验证了模型的正确性;进而分析了... 详细信息

基于咬合型管幕试件的抗弯性能试验,研究了咬合型管幕试件的力学性能及破坏形态。为进一步研究关键结构参数对咬合型管幕试件抗弯性能的影响,运用ABAQUS建立了咬合型管幕试件的有限元模型,并通过室内试验验证了模型的正确性;进而分析了钢管咬合程度、钢管壁厚及钢筋直径对咬合型管幕试件抗弯性能的影响。结果表明:咬合型管幕试件抗弯性能良好,试件最终发生延性破坏;钢管咬合程度、钢管壁厚对试件的抗弯承载力影响显著,钢筋直径对试件的抗弯承载力影响不明显。最后,给出了钢管咬合程度、钢管壁厚及钢筋直径与抗弯承载力的关系式;并通过多元线性回归得到了咬合型管幕试件抗弯承载力简化计算公式。

关键词：地下结构咬合型管幕抗弯承载力破坏模式回归分析

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基于LDA与双向GRU的借阅主题热度预测

软件导刊 2024年第7期23卷 51-57页

作者：陈志辉吴克晴陈嘉超秦泽豪江西理工大学理学院江西赣州341000 嘉兴学院信息科学与工程学院浙江嘉兴314000

图书借阅主题分析能够挖掘读者借阅喜好和阅读规律,通过使用借阅主题热度预测模型能够预测读者借阅主题热度变化趋势,对图书馆开展阅读推广活动具有重要意义。为了解决图书借阅主题提取、主题热度预测问题,提出基于LDA与双向GRU神经网... 详细信息

图书借阅主题分析能够挖掘读者借阅喜好和阅读规律,通过使用借阅主题热度预测模型能够预测读者借阅主题热度变化趋势,对图书馆开展阅读推广活动具有重要意义。为了解决图书借阅主题提取、主题热度预测问题,提出基于LDA与双向GRU神经网络的借阅主题热度预测模型。该算法通过LDA算法提取读者不同时间段中的借阅图书特征和借阅主题,在计算不同时间段借阅主题热度、构建借阅主题热度序列数据集的基础上,构造基于双向GRU神经网络的主题热度预测模型以预测未来主题热度变化趋势,并在厦门大学图书馆纸质文献借阅记录数据集上进行实验评估。实验结果表明,模型能准确获得借阅主题与关键词之间的关系,与机器学习等算法比较可知,该模型能有效降低借阅主题热度预测误差。

关键词：热度预测借阅主题发现深度学习双向门控循环单元潜在狄利克雷分配

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一种基于旋量理论的机器人关节结构误差对其精度影响的分析方法

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湖南工业大学学报 2020年第5期34卷 26-32页

作者：杨加超李光章晓峰马祺杰肖帆湖南工业大学机械工程学院湖南株洲412007

为提高工业机器人的定位精度,应用旋量理论,提出了一种分析关节误差源对机器人精度影响的分析方法。该方法通过分析机器臂关节两轴线在不同几何误差作用下的空间位置关系,将关节误差表示成旋量的形式,结合POE公式,给出了包含关节误差的... 详细信息

为提高工业机器人的定位精度,应用旋量理论,提出了一种分析关节误差源对机器人精度影响的分析方法。该方法通过分析机器臂关节两轴线在不同几何误差作用下的空间位置关系,将关节误差表示成旋量的形式,结合POE公式,给出了包含关节误差的机器人正向运动学显式表达式,并以一个三关节机械臂为例,用Adams仿真验证了该方法的正确性。

关键词：工业机器人精度分析旋量 POE公式