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An ensemble machine learning model to uncover potential sites of hazardous waste illegal dumping based on limited supervision experience

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Fundamental Research 2024年第4期4卷 972-978页

作者： Jinghua Geng Yimeng Ding Wenjun Xie Wen Fang Miaomiao Liu Zongwei Ma Jianxun yang Jun Bi State Key Laboratory of Pollution Control and Resource Reuse School of the EnvironmentNanjing UniversityNanjing 210023 China

With the soaring generation of hazardous waste(HW)during industrialization and urbanization,HW illegal dumping continues to be an intractable global *** in developing regions with lax regulations,it has become a major source of soil and groundwater *** dominant challenge for HW illegal dumping supervision is the invisibility of dumping sites,which makes HW illegal dumping difficult to be found,thereby causing a long-term adverse impact on the *** to utilize the limited historic supervision records to screen the potential dumping sites in the whole region is a key challenge to be *** this study,a novel machine learning model based on the positive-unlabeled(PU)learning algorithm was proposed to resolve this problem through the ensemble method which could iteratively mine the features of limited historic *** of the random forest-based PU model showed that the predicted top 30%of high-risk areas could cover 68.1%of newly reported cases in the studied region,indicating the reliability of the model *** novel framework will also be promising in other environmental management scenarios to deal with numerous unknown samples based on limited prior experience.

关键词： Hazardous waste Illegal dumping site Positive-unlabeled machine learning Probability prediction Model interpretation

通信受限条件下多无人机协同环境覆盖路径规划

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中国惯性技术学报 2024年第3期32卷 273-281页

作者：陈洋周锐武汉科技大学信息科学与工程学院武汉430081 武汉科技大学冶金自动化与检测技术教育部工程研究中心武汉430081

多无人机协同覆盖旨在有效分配多个无人机任务,实现给定区域的快速、高效全覆盖。然而,在现实应用场景中常常因为无人机之间距离超出通信范围,信号传输受阻,导致无人机之间的协作和信息交互面临极大挑战。为此,提出一种基于Deep Q Netwo... 详细信息

多无人机协同覆盖旨在有效分配多个无人机任务,实现给定区域的快速、高效全覆盖。然而,在现实应用场景中常常因为无人机之间距离超出通信范围,信号传输受阻,导致无人机之间的协作和信息交互面临极大挑战。为此,提出一种基于Deep Q Networks(DQN)的多无人机路径规划方法。采用通信中断率和最大通信中断时间两个指标来评价路径质量,通过构建与指标相关的奖励函数,实现了无人机团队的自主路径决策。仿真实验表明,所提方法在最短路径上可以与传统优化算法效果保持一致,权衡路径下在增加20%路径长度的情况下可以降低80%通信中断率,在全通信路径下则可以实现100%的全过程连接通信,因此可以根据不同的通信环境生成高效覆盖所有环境节点的路径。

关键词：环境覆盖多无人机通信约束深度Q网络路径规划

Selective removal of Cr(Ⅵ)using polyvinylpyrrolidone and polyacrylamide co-modified MoS_(2) ccomposites by adsorption combined with reduction

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Chinese Chemical Letters 2024年第6期35卷 524-530页

作者： Shuqi Yu Yu yang Keisuke Kuroda Jian Pu Rui Guo Li-An Hou State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 100875China Department of Environmental and Civil Engineering Toyama Prefectural UniversityImizuToyama 939-0398Japan Institute for the Advanced Study of Sustainability United Nations UniversityJingumae 5-53-70Shibuya-kuTokyo 150-8925Japan Technical Centre for Soil Agriculture and Rural Ecology and EnvironmentMinistry of Ecology and EnvironmentBeijing 100012China

Cr(Ⅵ),one of the most hazardous metal pollutants,poses significant threats to the environment and human ***,a novel MoS_(2) composite(MoS_(2)/PVP/PAM)modified by polyvinylpyrrolidone(PVP)and polyacrylamide(PAM)was synthesized to enhance the removal of Cr(Ⅵ).Characterization analysis including SEM,XRD,FTIR,and XPS indicated that PVP and PAM could increase the interlayer spacing and the dispersibility of MoS_(2),and introduce pyrrolic N and amino functional *** batch experiments showed that MoS_(2)/PVP/PAM represented excellent Cr(Ⅵ)removal performance over a wide p H range,and exhibited a significantly higher maximum Cr(Ⅵ)adsorption capacity(274.73 mg/g,at p H 3.0,and 298 K)than pure MoS_(2).The adsorption of Cr(Ⅵ)followed Langmuir and pseudo-second-order kinetic model,which was a homogeneous monolayer chemisorption ***_(2)/PVP/PAM showed stable removal of Cr(Ⅵ)in the presence of humic acid(HA),interfering cations and anions at different ***,it had excellent selectivity for Cr(Ⅵ)(K_(d) value of 1.69×10^(7)m L/g)when coexisting with a variety of competing *** characterization revealed that Cr(Ⅵ)was reduced to low toxicity Cr(Ⅲ)by Mo^(4+)and S^(2-),and then chelated on the surface of the adsorbent by pyrrolic *** research expanded the design concept for MoS_(2) composites by demonstrating the potential of MoS_(2)/PVP/PAM as a promising material for selective elimination of Cr(Ⅵ)in water.

关键词： Polyvinylpyrrolidone Polyacrylamide MoS_(2) Cr(Ⅵ)removal Adsorbent Reduction

基于TRIZ理论的发动机试验羽流压力测量系统改进

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航空学报 2024年第11期45卷 146-157页

作者：曹纯杨龙北京航天试验技术研究所北京100074

羽流压力是火箭发动机高空模拟试验测量的重要参数之一,能够有效地反映发动机的工作性能。针对某型号固体火箭发动机羽流高空模拟试验压力测量系统存在的未能测量到羽流场压力变化的问题,基于发明问题解决理论(TRIZ)分析系统存在的问题... 详细信息

羽流压力是火箭发动机高空模拟试验测量的重要参数之一,能够有效地反映发动机的工作性能。针对某型号固体火箭发动机羽流高空模拟试验压力测量系统存在的未能测量到羽流场压力变化的问题,基于发明问题解决理论(TRIZ)分析系统存在的问题,开展问题复现试验。依据问题定位结果,利用物理矛盾和物质-场模型的问题解决原理提出解决方案;并结合现场情况选择羽流压力测量系统的改进方案,对压力传感器内部电路进行绝缘处理,提升压力测量系统性能。改进后的系统满足发动机试验的羽流压力测量需求。

关键词：羽流压力测量发明问题解决理论(TRIZ) 因果链分析物理矛盾物质-场模型

Asymmetric Synthesis of Dihydrospirotryprostatin B via a Silica Gel-Mediated Cyclization of Tryptamine-Ynamide

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Chinese Journal of Chemistry 2024年第12期42卷 1355-1359页

作者： Changhong Han Lu yang Kaizong Yao Sen Zhang Jiayue Fu Hanyang Sun Hongsheng Xu Bin Lin Maosheng Cheng Yongxiang Liu Key Laboratory of Structure:Based Drug Design and Discovery of Ministry of Education Shenyang Pharmaceutical UniversityShenyangLiaoning 110016China Wuya College of Innovation Shenyang Pharmaceutical UniversityShenyangLiaoning 110016China Institute of Drug Research in Medicine Capital of China BenxiLiaoning 117000China Zhejiang Shapuaisi Pharmaceutical Co. LtdPinghuZhejiang 314299China

Comprehensive Summary An asymmetric synthesis of dihydrospirotryprostatin B was achieved in 15 steps(8 purifications)from *** main feature of our synthetic strategy is the efficient construction of spirocyclic oxindole intermediate containing a chiral quaternary carbon center,involving the silica gel-mediated cyclization of tryptamine-ynamide and oxidation under neat conditions.

关键词： Asymmetric synthesis Alkaloids Dihydrospirotryprostatin B Tryptamine-ynamide Cross-coupling Silica gel-mediated cyclization Oxidation

Disruption of a microvitellogenin gene impairs eggshell formation in Mythimna separata

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Journal of Integrative Agriculture 2024年第11期23卷 3801-3811页

作者： Lingling Li Junhong Fu Changgeng Dai Yuhang Zhou yang Hu Hongbo Li Institute of Plant Protection Guizhou Academy of Agricultural Sciences Guizhou Provincial Key Laboratory for Agricultural Pest Management of the Mountainous Region School of Agriculture Institute of Entomology Guizhou University Crop Genetic Resources and Germplasm Innovation in Karst Region Ministry of Agriculture and Rural Affairs

Microvitellogenin(mVg) belongs to the lepidopteran-specific lipoprotein＿11 super family and is thought to be involved in insect reproduction. However, the function of mVg in reproduction has not been established. In this study, we identified and characterized MsmVg in Mythimna separata, a destructive insect pest of grain crops. MsmVg is comprised of a 1,310 bp open reading frame(ORF) encoding 437 amino acids. Structural analysis showed that MsmVg contains three conserved domains in the lipoprotein＿11 super family, including the all-α-N-terminal domain(NTD), a Pseudomonas putida homologous domain(PPD), and an all-β-C-terminal domain(CTD). MsmVg was highly expressed in mature female adults and enriched in the ovaries of 3-day-old female adults. Disruption of MsmVg by RNA interference did not change the expression of MsmVg, vitellogenin(MsVg) or the vitellogenin receptor(MsVgR) in fat bodies, but it inhibited their transcription in ovaries. Phenotype analysis showed that knockdown of MsmVg did not affect yolk deposition in ovaries, but impaired eggshell formation and led to a reduction in the reproductive capacity. Furthermore, knockdown of MsmVg significantly inhibited the expression of genes associated with eggshell formation(MsChP1-3 and MsFcP3C). Taken together, these data suggest that MsmVg plays an important role in female reproduction by affecting eggshell formation in M. separata, which provides a potential target for managing this insect pest.

关键词： microvitellogenin Mythimna separata reproduction RNA interference

Experimental Investigation of Lee–yang Criticality Using Non-Hermitian Quantum System

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Chinese Physics Letters 2024年第5期41卷 1-11页

作者：蓝子桁刘文权伍旸叶翔宇杨哲森段昌奎王亚荣星 CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences University of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026China Hefei National Laboratory University of Science and Technology of ChinaHefei 230088China School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China Kavli Institute for Theoretical Sciences Chinese Academy of SciencesBeijing 100190China

Lee–yang theory clearly demonstrates where the phase transition of many-body systems occurs and the asymptotic behavior near the phase transition using the partition function under complex parameters. The complex parameters make the direct investigation of Lee–yang theory in practical systems challenging. Here we construct a non-Hermitian quantum system that can correspond to the one-dimensional Ising model with imaginary parameters through the equality of partition functions. By adjusting the non-Hermitian parameter,we successfully obtain the partition function under different imaginary magnetic fields and observe the Lee–yang zeros. We also observe the critical behavior of free energy in vicinity of Lee–yang zero that is consistent with theoretical prediction. Our work provides a protocol to study Lee–yang zeros of the one-dimensional Ising model using a single-qubit non-Hermitian system.

关键词： functions partition imaginary

Exposure to microplastics induces lower survival,oxidative stress,disordered microbiota and altered metabolism in the intestines of grass carp(Ctenopharyngodon idella)

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Aquaculture and Fisheries 2024年第5期9卷 785-794页

作者： Xuewen Jia yang Liu Yan He Hongyan Yu Yuting Liu Yubang Shen Xiaoyan Xu Jiale Li Key Laboratory of Freshwater Aquatic Genetic Resources Ministry of Agriculture and Rural Affairs Shanghai Ocean UniversityShanghai201306China National Demonstration Center for Experimental Fisheries Science Education Shanghai Ocean UniversityShanghai201306China Shanghai Engineering Research Center of Aquaculture Shanghai Ocean UniversityShanghai201306China

There are major gaps in illustrating the risk to freshwater fish that are exposed to environmental microplastics(MPs),even though MPs in freshwater environments has drawn much *** explore the potentially negative effects of microplastics on freshwater fish,grass carp(averaging 9.215±0.035g)were exposed to microplastics(32-40μm in diameter)at two environmental concentrations(100 and 1000μg/L)for 21 days,and evaluated for physio-biochemical performance,gut microbiome,and metabolome *** exposure,microplastics were detected in the intestine and within basal nuclei and goblet cells *** enzyme activities(superoxide dismutase and catalase)also significantly decreased within the intestines(P<0.05).Through 16S rRNA gene sequencing analysis,a decrease in diversity and richness was observed in the MPs-H and MPs-L *** abundance of opportunistic pathogens increased and beneficial bacteria decreased in both MP *** example,Acinetobacter and Bosea proportions were higher in the MPs-L group,while Bacteroides and Shewanella increased in the MPs-H ***,abundance of Lactobacillus decreased both in the MPs-H and MPs-L *** analysis revealed primary bile acid biosynthesis metabolism upregulated in the MPs-L and purine metabolism downregulated in the MPs-H ***,an integration analysis of the gut microbiome and metabolomics identified significant associations between several bacteria taxa and metabolites related to intestinal *** together,these results highlighted the negative effects on intestinal morphology,oxidative stress,and microbiome and emphasized the relationship between microbiota and metabolites in response to microplastics,which could provide comprehensive insights into the potential risks of MPs on freshwater fish intestines.

关键词： Microplastics Oxidative stress Metabolomics Microbiome Grass carp Intestine

Multi-Task Visual Semantic Embedding Network for Image-Text Retrieval

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Journal of Computer Science & Technology 2024年第4期39卷 811-826页

作者： Xue-yang Qin Li-Shuang Li Jing-Yao Tang Fei Hao Mei-Ling Ge Guang-Yao Pang School of Computer Science and Technology Dalian University of TechnologyDalian 116024China School of Computer Science Shaanxi Normal UniversityXi’an 710119China School of Computer Engineering Weifang UniversityWeifang 261061China Guangxi Colleges and Universities Key Laboratory of Intelligent Industry Software Wuzhou UniversityWuzhou 543002 China

Image-text retrieval aims to capture the semantic correspondence between images and texts,which serves as a foundation and crucial component in multi-modal recommendations,search systems,and online *** mainstream methods primarily focus on modeling the association of image-text pairs while neglecting the advantageous impact of multi-task learning on image-text *** this end,a multi-task visual semantic embedding network(MVSEN)is proposed for image-text ***,we design two auxiliary tasks,including text-text matching and multi-label classification,for semantic constraints to improve the generalization and robustness of visual semantic embedding from a training ***,we present an intra-and inter-modality interaction scheme to learn discriminative visual and textual feature representations by facilitating information flow within and between ***,we utilize multi-layer graph convolutional networks in a cascading manner to infer the correlation of image-text *** results show that MVSEN outperforms state-of-the-art methods on two publicly available datasets,Flickr30K and MSCOCO,with rSum improvements of 8.2%and 3.0%,respectively.

关键词： image-text retrieval cross-modal retrieval multi-task learning graph convolutional network