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Rapid detection and risk assessment of soil contamination at lead smelting site based on machine learning

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Transactions of Nonferrous Metals Society of China 2024年第9期34卷 3054-3068页

作者： Sheng-guo XUE jing-pei feng Wen-shun KE Mu LI Kun-yan QIU Chu-xuan LI Chuan WU Lin GUO School of Metallurgy and Environment Central South UniversityChangsha 410083China Henan Key Laboratory of Monitoring and Remediation in Heavy Metal Polluted Soil Jiyuan 454650China Henan Academy of Geology Zhengzhou 450000China

A general prediction model for seven heavy metals was established using the heavy metal contents of 207soil samples measured by a portable X-ray fluorescence spectrometer(XRF)and six environmental factors as model correction *** eXtreme Gradient Boosting(XGBoost)model was used to fit the relationship between the content of heavy metals and environment characteristics to evaluate the soil ecological risk of the smelting *** results demonstrated that the generalized prediction model developed for Pb,Cd,and As was highly accurate with fitted coefficients(R^(2))values of 0.911,0.950,and 0.835,*** presented the highest ecological risk,and there existed high potential ecological risk at some positions with different depths due to high mobility of ***,the application of machine learning significantly increased the accuracy of pXRF measurements,and identified key environmental *** adapted potential ecological risk assessment emphasized the need to focus on Pb,Cd,and As in future site remediation efforts.

关键词： smelting site potentially toxic elements X-ray fluorescence potential ecological risk machine learning

Designing Electronic Structures of Multiscale Helical Converters for Tailored Ultrabroad Electromagnetic Absorption

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Nano-Micro Letters 2025年第1期17卷 439-455页

作者： Zhaobo feng Chongbo Liu Xin Li Guangsheng Luo Naixin Zhai Ruizhe Hu jing Lin Jinbin Peng Yuhui Peng Renchao Che Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle School of Environmental and Chemical EngineeringNanchang Hangkong UniversityNanchang 330063People’s Republic of China School of Physics and Materials Nanchang UniversityNanchang 330031People’s Republic of China Key Laboratory of Nondestructive Testing Ministry of EducationNanchang Hangkong UniversityNanchang 330063People’s Republic of China Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsAcademy for Engineering and TechnologyFudan UniversityShanghai 200438People’s Republic of China

Atomic-scale doping strategies and structure design play pivotal roles in tailoring the electronic structure and physicochemical property of electromagnetic wave absorption(EMWA)***,the relationship between configuration and electromagnetic(EM)loss mechanism has remained ***,drawing inspiration from the DNA transcription process,we report the successful synthesis of novel in situ Mn/N co-doped helical carbon nanotubes with ultrabroad EMWA *** calculation and EM simulation confirm that the orbital coupling and spin polarization of the Mn–N4–C configuration,along with cross polarization generated by the helical structure,endow the helical converters with enhanced EM *** a result,HMC-8 demonstrates outstanding EMWA performance,achieving a minimum reflection loss of−63.13 dB at an ultralow thickness of 1.29 *** precise tuning of the graphite domain size,HMC-7 achieves an effective absorption bandwidth(EAB)of 6.08 GHz at 2.02 mm ***,constructing macroscale gradient metamaterials enables an ultrabroadband EAB of 12.16 GHz at a thickness of only 5.00 mm,with the maximum radar cross section reduction value reaching 36.4 dB *** innovative approach not only advances the understanding of metal–nonmetal co-doping but also realizes broadband EMWA,thus contributing to the development of EMWA mechanisms and applications.

关键词： Metal-nonmetal co-doping 3d-2p orbital coupling Spin polarization Helical structure Broadband EM wave absorption

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加强国际船舶代理业务管理的建议

交通标准化 2008年第4期36卷 22-25页

作者：荆培峰日照海事局山东日照276826

为进一步规范国际船舶代理行为,加强海事监管,借鉴其他口岸查验机构的做法,提出有关加强国际船舶代理业务管理的建议和设想,对于规范船舶代理市场行为,提高行业整体水平,建立统一公平竞争的市场秩序和船舶通关秩序,将起到积极的作用。

关键词：船舶代理管理

Depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 335-345页

作者： feng Zhang Chenyang Zhang Linlin Wu Wei Sun Hongliang Zhang Jianhua Chen Yong pei Songjiang Li Engineering Research Center of Ministry of Education for Carbon Emission Reduction in Metal Resource Exploitation and Utilization Hunan International Joint Research Center for Efficient and Clean Utilization of Critical Metal Mineral ResourcesSchool of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China State Key Laboratory of Mineral Processing Beijing General Research Institute of Mining&MetallurgyBeijing 100160China Hunan Provincial Key Laboratory of Micro&Nano Materials Interfaces Science College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China Department of Chemistry Xiangtan UniversityXiangtan 411105China China Railway Resource Group Co.Ltd Beijing 102300China

The depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite still lacked in-depth ***,the depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite was further systematically investigated with experiments and density functional theory(DFT)*** X-ray photoelectric spectroscopy(XPS)results,DFT calculation results,and frontier molecular orbital analysis indicated that sulfite ions were difficult to be adsorbed on sphalerite surface,suggesting that sulfite ions achieved depression effects on sphalerite through other non-adsorption ***,the oxygen content in the surface of sphalerite treated with sulfite ions in creased,which enhanced the hydrophilicity of the sphalerite and further increased the difference in hydrophilicity between sphalerite and ***,sulfite ions were chelated with lead ions to form PbSO_(3)in *** hydrophilic PbSO_(3)was more easily adsorbed on sphalerite than *** interaction between sulfite ions and lead ions could effectively inhibit the activation of *** addition the UV spectrum showed that after adding sulfite ions,the peak of perxanthate in the sphalerite treated xanthate solution was significantly stronger than that in the galena with xanthate solution,indicating that xanthate interacted more readily with sulfite ions and oxygen mo lecules within the sphalerite system,leading to the formation of ***,sulfite ions hardly depressed the flotation of ga lena and could promote the flotation of galena to some *** study deepened the understanding of the depression mechanism o sulfite ions on sphalerite and Pb^(2+)activated sphalerite.

关键词： sphalerite galena sulfite ion density functional theory depression mechanism

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氨基酸共聚物修饰的生物相容性MRI造影剂

波谱学杂志 2016年第4期33卷 635-645页

作者：湛游洋薛蓉祝云龙李晓晶裴奉奎冯江华中国科学院长春应用化学研究所吉林长春130022 中国科学院大学北京100049 厦门大学电子科学系福建厦门361005

通过天门冬氨酸(Asp)、异亮氨酸(Ile)热缩聚反应,制备了天门冬氨酸-异亮氨酸共聚物(AI),通过乙二胺(EDA)胺化,并与1,4,7,10-四氮杂环十二烷-1,4,7,10-四羧酸(DOTA)连接,再与钆离子(Gd3+)络合,合成了生物相容性大分子磁共振成像(MRI)造... 详细信息

通过天门冬氨酸(Asp)、异亮氨酸(Ile)热缩聚反应,制备了天门冬氨酸-异亮氨酸共聚物(AI),通过乙二胺(EDA)胺化,并与1,4,7,10-四氮杂环十二烷-1,4,7,10-四羧酸(DOTA)连接,再与钆离子(Gd3+)络合,合成了生物相容性大分子磁共振成像(MRI)造影剂——AI-EDA-DOTA-Gd.运用红外光谱(IR)、核磁共振(NMR)、电感耦合等离子谱(ICP)等方法对其进行结构表征,并通过弛豫性能、溶血性质、急性毒性及动物体内成像对其进行综合评价.体外弛豫结果表明,AI-EDA-DOTA-Gd的纵向弛豫效率(r_1=12.6mmol^(–1)×L×s^(–1))是商用造影剂Gd-DOTA(r_1=5.8 mmol^(–1)×L×s^(–1))的2.2倍.动物组织生理切片和溶血性实验结果说明其具有良好的生物相容性和较低的毒性.动物体内成像结果显示,AI-EDA-DOTA-Gd的最佳成像时间为30~70 min,注射AI-EDA-DOTA-Gd后的肝脏组织信号相比于未注射造影剂时增强了约(55.1±5.7)%.

关键词： MRI造影剂弛豫效率氨基酸共聚物大分子配合物生物相容性

Study on the Biological Activity of 3-Aroyl-5-substituted Thiophene Derivatives Based on the CoMFA Method

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Chinese Journal of Structural Chemistry 2020年第11期39卷 1978-1984页

作者： feng Hui feng Chang-Jun CAO jing-pei Key Laboratory of Coal Processing and Efficient Utilization(Ministry of Education) Xuzhou 221116China School of Chemistry&Chemical Engineering Xuzhou University of TechnologyXuzhou 221018China

A three-dimensional quantitative structure-activity relationship(3 D-QSAR) study was conducted to analyze the A1 AR density(Bmax) of 56 3-aroyl-5-substituted thiophene derivatives(ASTDs) in human A1 Chinese hamster ovary(hA1 CHO) membranes by the comparative molecular field analysis(CoMFA) method. A training set of 45 compounds was used to establish the predictive model, which was verified by the test set of 17 compounds containing template molecule and 5 newly designed molecules. The cross-validation(R2 cv) and non-cross-validation(R2) coefficients of the training set were 0.655 and 0.959, respectively. The model was used to predict the activities of the compounds of the training and test sets, and the results indicated that the models had strong stability and good prediction ability. According to model analysis, the contribution of steric and electrostatic fields was 51.4% and 48.6%, respectively. Based on the 3 D contour maps, five excellent ASTDs agonists were designed, which need to be further verified by biomedical experiments.

关键词： 3-aroyl-5-substituted thiophene derivatives(ASTDs) A1AR density(Bmax) three-dimensional quantitative structure-activity relationship comparative molecular field analysis

An Unprecedented Efficiency with Approaching 21%Enabled by Additive‑Assisted Layer‑by‑Layer Processing in Organic Solar Cells

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Nano-Micro Letters 2025年第2期17卷 372-375页

作者： Shuai Xu Youdi Zhang Yanna Sun pei Cheng Zhaoyang Yao Ning Li Long Ye Lijian Zuo Ke Gao Key Laboratory of Advanced Green Functional Materials College of ChemistryChangchun Normal UniversityChangchun 130032People’s Republic of China Shandong Provincial Key Laboratory for Science of Material Creation and Energy Conversion School of Chemistry and Chemical EngineeringShandong UniversityQingdao 266237People’s Republic of China College of Polymer Science and Engineering Sichuan UniversityChengdu 610065People’s Republic of China State Key Laboratory and Institute of Elemento‑Organic Chemistry Centre of Nanoscale Science and Technology and Key Laboratory of Functional Polymer MaterialsRenewable Energy Conversion and Storage Center(RECAST)College of ChemistryNankai UniversityTianjin 300071People’s Republic of China Institute of Polymer Optoelectronic Materials and Devices State Key Laboratory of Luminescent Materials and Devices South China University of TechnologyGuangzhou 510640People’s Republic of China Tianjin Key Laboratory of Molecular Optoelectronic Sciences School of Materials Science and EngineeringTianjin UniversityTianjin 300350People’s Republic of China State Key Laboratory of Silicon Materials MOE Key Laboratory of Macromolecular Synthesis and FunctionalizationDepartment of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China

Recently published in Joule,feng Liu and colleagues from Shanghai Jiaotong University reported a record-breaking 20.8%power conversion efficiency in organic solar cells(OSCs)with an interpenetrating fibril network active layer morphology,featuring a bulk p-in structure and proper vertical segregation achieved through additive-assisted layer-by-layer *** optimized hierarchical gradient fibrillar morphology and optical management synergistically facilitates exciton diffusion,reduces recombination losses,and enhances light capture *** approach not only offers a solution to achieving high-efficiency devices but also demonstrates the potential for commercial applications of OSCs.

关键词： Organic solar cells Additive-assisted layer-by-layer processing Three-dimensional fibril morphology Bulk p-i-n structure Optical management

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基于文献挖掘视角的组学研究脉络梳理

中华医学图书情报杂志 2018年第3期27卷 44-49页

作者：李靖宇程景民贺培凤田玥于琦山西医科大学管理学院山西太原030001

目的:梳理组学研究脉络,分析组学研究热点趋势,帮助科研工作者把握研究方向,为科研管理部门在组学研究方面的资助提供决策支持。方法:利用E-utilities下载1986-2016年Pub Med数据库收录的含有"-Omics/Omic/Omes/Ome"的题录信息27 040 81... 详细信息

目的:梳理组学研究脉络,分析组学研究热点趋势,帮助科研工作者把握研究方向,为科研管理部门在组学研究方面的资助提供决策支持。方法:利用E-utilities下载1986-2016年Pub Med数据库收录的含有"-Omics/Omic/Omes/Ome"的题录信息27 040 819条,在题录信息的题目和摘要中对以"-Omics/Omic/Omes/Ome"结尾的词进行标注、筛选,并利用词频分析法、共现分析法、社会网络分析法对筛选结果进行分析。结果:获得组学相关记录共346 977条,文献发表量逐年递增,自2000年后呈井喷式增长。各类单一组学的文献发表量均呈逐年递增的趋势,其中基因组学文献发表量最多。2014年之后,转录组学的文献发表量赶超了蛋白质组学,成为继基因组学之后的第二大组学类型。转录组学、线粒体基因组学与基因组学共现的文献量在某一时间节点后呈井喷式增长,其余组学类型与基因组学共现的文献量都稳定增长。结论:后基因组时代把组学研究推向了高潮,无论是数量还是种类都出现了井喷式的增长。多类型组学的融合研究越来越受科研人员的关注。

关键词：组学文献挖掘共现分析可视化

Modelling and Dynamic Characteristics for a Non-metal Pressurized Reservoir with Variable Volume

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Chinese Journal of Mechanical Engineering 2022年第2期35卷 159-173页

作者： pei Wang jing Yao Baidong feng Mandi Li Dingyu Wang School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China Advanced Manufacturing Forming Technology and Equipment Qinhuangdao 066004China Hebei Provincial Key Laboratory of Heavy Fluid Power Transmission and Control Yanshan UniversityQinhuangdao 066004China

With the increasing demand to reduce emissions and save energy,hydraulic reservoirs require new architecture to optimize their weight,space,and *** open reservoirs are large,heavy,and easily polluted,and threaten the operation of hydraulic systems.A closed reservoir provides the advantages of small volume and light weight,compared to open *** this study,a non-metallic pressure reservoir with variable volume is designed and manufactured for closed-circuit hydraulic *** reservoir housing is made of rubber,and the Mooney-Rivlin model is chosen based on the rubber strain *** FEA simulation for the reservoir is performed using ANSYS Workbench to obtain the structural *** major contribution is the establishment of mathematical models for this reservoir,including the volume equation changing with height,flow equation,and force balance equation,to explore the output characteristics of this *** on these results,simulation models were built to analyze the output characteristics of the ***,the test rig of a conventional hydraulic system was transformed into a closed-circuit asymmetric hydraulic system for the reservoir,and preliminary verification experiments were conducted on *** results demonstrate that the designed reservoir can absorb and discharge oil and supercharge pump inlet to benefit system *** changes in the volume and pressure with displacements under different volume ratios and frequencies were obtained,which verified the accuracy of the mathematical *** to its lightweight design and small volume,the reservoir can replace conventional open reservoirs,and this lays a foundation for future theoretical research on this reservoir.

关键词： Hydraulic reservoir Variable volume Pressure reservoir Non-metal Lightweight