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长期施用有机肥对土壤微塑料赋存及迁移特征的影响

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环境科学 2024年第4期45卷 2304-2312页

作者：王长远马啸驰郭德杰刘新红马艳罗佳江苏省农业科学院农业资源与环境研究所南京210014 国家农业环境六合观测实验站南京210014 江苏大学环境与安全工程学院镇江212013

为探明设施土壤中微塑料的赋存特征与施肥模式、种植年限及土壤深度之间的响应关系,通过现场采样、显微镜观察、傅里叶变换红外光谱(FTIR)和扫描电子显微镜(SEM)等方法,对长期施用有机肥土壤中微塑料丰度、形状、粒径、颜色、种类和表... 详细信息

为探明设施土壤中微塑料的赋存特征与施肥模式、种植年限及土壤深度之间的响应关系,通过现场采样、显微镜观察、傅里叶变换红外光谱(FTIR)和扫描电子显微镜(SEM)等方法,对长期施用有机肥土壤中微塑料丰度、形状、粒径、颜色、种类和表面形貌特征及有机肥中微塑料的丰度、粒径和种类进行分析.结果表明,设施土壤中不同种植年限下(2016~2021年)表层土壤中微塑料的平均丰度随着种植年限的升高而升高,化肥(CF)、有机肥(OF)和生物炭+有机肥(BOF)处理中微塑料丰度不同,其中每年OF处理微塑料的丰度最高,2021年长期施用OF的表层土壤微塑料丰度最高,为543.33 n·kg^(-1).3种施肥处理土壤中微塑料平均年增长速率分别为11.16%、12.61%和9.17%.微塑料丰度在不同深度土层中表现为随土层深度的增加而显著降低,且BOF处理中微塑料向深层土壤迁移效率最高.微塑料形状主要为纤维状、碎片状、颗粒状和薄膜状,在0~40 cm深度土壤中,纤维状微塑料在3种施肥类型土壤中均占主导地位.在40~60 cm土壤中CF处理无纤维状和薄膜状微塑料,颗粒状微塑料占比最高(57.14%);OF处理无薄膜状微塑料,颗粒状微塑料和纤维状微塑料占比最高(36.00%);BOF处理中占比最高的为颗粒状微塑料(41.18%),占比最少的为薄膜状微塑料(5.88%). 3种施肥处理土壤中小尺寸(<0.5 mm)微塑料占比最高,在CF、OF和BOF这3种处理土壤中PE为主要微塑料种类,且在微塑料表面均呈现多孔、撕裂、裂痕和磨损等特点.有机肥中微塑料平均丰度高达577.78 n·kg^(-1).长期施用有机肥的设施土壤中微塑料丰度与有机肥密切相关,且微塑料迁移也与施用肥料种类密切相关.研究对于明晰不同长期施肥模式下设施土壤中微塑料的分布特征和迁移具有重要意义.

关键词：微塑料有机肥土壤深度设施农田迁移

Finite-time Prescribed Performance Time-Varying Formation Control for Second-Order Multi-Agent Systems With Non-Strict Feedback Based on a Neural Network Observer

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1039-1050页

作者： chi ma Dianbiao Dong the School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China

This paper studies the problem of time-varying formation control with finite-time prescribed performance for nonstrict feedback second-order multi-agent systems with unmeasured states and unknown *** eliminate nonlinearities,neural networks are applied to approximate the inherent dynamics of the *** addition,due to the limitations of the actual working conditions,each follower agent can only obtain the locally measurable partial state information of the leader *** address this problem,a neural network state observer based on the leader state information is ***,a finite-time prescribed performance adaptive output feedback control strategy is proposed by restricting the sliding mode surface to a prescribed region,which ensures that the closed-loop system has practical finite-time stability and that formation errors of the multi-agent systems converge to the prescribed performance bound in finite ***,a numerical simulation is provided to demonstrate the practicality and effectiveness of the developed algorithm.

关键词： Finite-time control multi-agent systems neural network prescribed performance control time-varying formation control

Existence of long-range magnetic order in Heisenberg spin nanoribbons with edge modification

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Communications in Theoretical Physics 2024年第7期76卷 134-144页

作者： Da-cheng ma Ling-yi Cui Chu-xiao Sun xiao-dan chi Zheng-Nan XianYu An Du College of Science Northeastern UniversityShenyang 110819China Department of Basic Science Dalian Naval AcademyDalian 116018China Department of Physics College of SciencesShenyang University of Chemical TechnologyShenyang 110142China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern UniversityChina Key Laboratory of Data Analytics and Optimization for Smart Industry(Northeastern University) Ministry of EducationChina

Long-range magnetic order appears on a side decorated Heisenberg spin nanoribbon at nonzero temperature,although no spontaneous magnetization exists in a one-or two-dimensional isotropic Heisenberg model at any nonzero temperature according to the Mermin-Wagner *** use of the spin Green's function method,we calculated the magnetizations of Heisenberg nanoribbons decorated by side spins with single-ion anisotropy and found that the system exhibits a nonzero transition temperature,whether the decorated edge spins of the system link together or separate from each *** the width of the nanoribbon achieves infinite limit,the transition temperatures of the system tend to the same finite constant eventually whether one edge or both edges are decorated by side spins in the *** results reveal that the magnetism of a low-dimensional spin system is different from that of a threedimensional spin *** the single-ion anisotropy of edge spins in a Heisenberg spin nanoribbon can be modulated by an electric field experimentally,various useful long-range magnetic orders of the system can be *** work can provide a detailed theoretical basis for designing and fabricating next-generation low-dimensional magnetic random-access memory.

关键词： Nanoribbon magnetic anisotropy long-range magnetic order Heisenberg model transition temperature

Fluoro-functionalized plant biomass adsorbent:Preparation and application in extraction of trace perfluorinated compounds from environmental water samples

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Journal of Environmental Sciences 2024年第3期137卷 703-715页

作者： Xi Tan Yan Shi Chun-Feng ma Quan chi Yu-Hang Yang Wen-Xiang Zhang Hua-Ming xiao Xian Wang Key Laboratory of Analytical Chemistry of the State Ethnic Affairs Commission School of Chemistry and Materials ScienceSouth-Central Minzu UniversityWuhan 430074China School of Pharmaceutical Sciences South-Central Minzu UniversityWuhan 430074China Key Laboratory of Oilseeds Processing of Ministry of Agriculture Hubei Key Laboratory of Lipid Chemistry and NutritionOil Crops Research Institute of the Chinese Academy of Agricultural SciencesWuhan 430062China

Perfuorinated compounds(PFCs)are toxic and widely present in the environment,and therefore effective adsorbents are required to remove PFCs from environmental *** the present study,a new type of fuorinated biomass materials was synthesized via an ingenious fuorosilanization *** adsorbents were applied for the adsorption of 13typical PFCs,including perfuorocarboxylic acids(PFCAs)and perfuorosulfonic acids(PFSAs).By comparing their adsorption performance,Fluorinated cedar slag(FCS)was discovered to have the best absorption efficiency and enabled highly efficient enrichment of *** adsorption recovery of FCS with the investigated PFCs is greater than 90%under the optimal adsorption *** to the high affinity of F-F sorbent-sorbate interaction,FCS had good adsorption capacities of PFCs from aqueous solution,with the maximum adsorption capacity of 15.80 mg/g for PFOS and 10.71 mg/g for PFOA,***,the adsorption time could be achieved in a short time(8 min).Using the FCS absorbent,an innovative FCS-solid phase extraction assisted with high performance liquid chromatography-electrospray-tandem mass spectrometry(FCS-SPE-HPLC-ESI-MS/MS)method was first developed to sensitively detect PFCs in the environmental water *** intra-day and inter-day recovery rates of the 13 compounds ranged from 90.7%-104.3%,with the RSD of 2.1%-4.7%(intra-day)and 2.5%-8.5%(inter-day),*** research demonstrates the potential of the newly fuoro-functionalized plant biomass to adsorb PFCs from environmental water,with the advantages of high adsorption efficiencies,high antiinterference,easy operation and low economic cost.

关键词： Fluoro-functionalized biomass Perfuorinated compounds(PFCs) Adsorption efficiency mass spectrometry(MS) Fluorinated cedar slag(FCS)

A new method for evaluating wedges of steel plates and strips

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Journal of Iron and Steel Research International 2024年第7期31卷 1719-1735页

作者： xiao-bao ma xiao-xin ma Tao Wang Zhong-kai Ren Yu-cheng Ren College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024ShanxiChina Ministry of Education Engineering Research Center of Advanced Metal Composite Forming Technology and Equipment Taiyuan University of TechnologyTaiyuan 030024ShanxiChina National Key Laboratory of Metal Forming Technology and Heavy Equipment Taiyuan University of TechnologyTaiyuan 030024ShanxiChina china National Heavy machinery Research Institute Co. Ltd.Xi'an 710018ShaanxiChina Faculty of Mechanical Engineering Hebei University of ArchitectureZhangjiakou 075000HebeiChina

To overcome the inaccuracy problem of the traditional wedge evaluation of steel plates and strips caused by the ran-domness of the thicknesses of two local points and improve the reliability of the wedge index,the double-centroid method for the wedge evaluation was proposed,and a model based on the centroid theory was ***,an integral model for the discrete thickness values of the cross-section profiles was *** discussion focused on the distinct characteristics of the two-point method,asymmetric method,and double-centroid method in evaluating the asymmetric distribution of *** three methods were employed to evaluate the wedge values of both the theoretical and measured cross-sections of steel plates and strips,and the accuracies of three wedge evaluation models were analyzed and *** results showed that the double-centroid method objectively reflects the degree and variation characteristics of the wedge values of the cross-sections of steel plates and strips,and this method is feasible,reliable,and outstanding.

关键词： Steel plate and strip Wedge Two-point method Double-centroid method Reliability

Effect of heat treatment on the microstructure,mechanical properties and fracture behaviors of ultra-high-strength SiC/Al-Zn-Mg-Cu composites

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International Journal of Minerals,Metallurgy and materials 2024年第10期31卷 2233-2243页

作者： Guonan ma Shize Zhu Dong Wang Peng Xue Bolüxiao Zongyi ma Shi-changxu Innovation Center for Advanced materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Centre of Excellence for Advanced materials Dongguan 523808China

A high-zinc composite,12vol%SiC/Al-13.3 Zn-3.27 Mg-1.07Cu(wt%),with an ultra-high-strength of 781 MPa was success-fully fabricated through a powder metallurgy method,followed by an extrusion *** effects of solid-solution and aging heat treat-ments on the microstructure and mechanical properties of the composite were extensively *** with a single-stage sol-id-solution treatment,a two-stage solid-solution treatment(470℃/1 h+480℃/1 h)exhibited a more effective solid-solution strengthen-ing owing to the higher degree of solid-solution and a more uniform *** to the aging hardness curves of the com-posite,the optimized aging parameter(100℃/22 h)was *** the aging temperature and time resulted in finer and more uniform nanoscale precipitates but only yielded a marginal increase in tensile *** fractography analysis revealed that intergranu-lar cracking and interface debonding were the main fracture mechanisms in the ultra-high-strength SiC/Al-Zn-Mg-Cu *** regions,such as the SiC/Al interface containing numerous compounds and the precipitate-free zones at the high-angle grain boundaries,were identified as significant factors limiting the strength enhancement of the *** compounds,including MgO,MgZn2,and Cu5Zn8,reduced the interfacial bonding strength,leading to interfacial debonding.

关键词： metal matrix composites heat treatment interfacial reaction mechanical properties fracture mechanism

Confined Mn^(2+) enables effective aerobic oxidation catalysis

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Science china Chemistry 2024年第5期67卷 1545-1553页

作者： Desheng Yuan Sicong ma xiao Kong chi Zhang Lin Chen Chengsheng Yang Lihua Wang Zhen Liu Lin Ye Yongmei Liu Rui ma Zhi-Pan Liu Yifeng Zhu Yong Cao Xinhe Bao Department of Chemical Physics University of Science and Technology of ChinaHefei 230026China Department of Chemistry Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsCollaborative Innovation Center of Chemistry for Energy MaterialsFudan UniversityShanghai 200438China Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Institute of Advanced Fluorine-Containing materials Zhejiang Normal UniversityJinhua 321004China State Key Laboratory of Catalysis National Laboratory for Clean EnergyCollaborative Innovation Center of Chemistry for Energy MaterialsDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Effective and mild activation of O_(2) is essential but challenging for aerobic oxidation. In heterogeneous catalysis, high-valence manganese oxide(e.g., +4) is known to be active for the oxidation, whereas divalent MnO is ineffective due to its limited capacity to supply surface oxygen and its thermodynamically unstable structure when binding O_(2) in reaction conditions. Inspired by natural enzymes that rely on divalent Mn^(2+), we discovered that confining Mn^(2+) onto the Mn_(2)O_(3) surface through a dedicated calcination process creates highly active catalysts for the aerobic oxidation of 5-hydroxymethylfurfural, benzyl alcohol, and *** Mn_(2)O_(3)-confined Mn^(2+) is undercoordinated and efficiently mediates O_(2) activation, resulting in 2–3 orders of magnitude higher activity than Mn_(2)O_(3) alone. Through low-temperature infrared spectroscopy, we distinguished low-content Mn^(2+) sites at Mn_(2)O_(3) surface, which are difficult to be differentiated by X-ray photoelectron spectroscopy. The combination of in-situ energydispersive X-ray absorption spectroscopy and X-ray diffraction further provides insights into the formation of the newly identified active Mn^(2+) sites. By optimizing the calcination step, we were able to increase the catalytic activity threefold *** finding offers promising frontiers for exploring active oxidation catalysts by utilizing the confinement of Mn^(2+)and oftenignored calcination skills.

关键词： confinement catalysis manganese oxide aerobic oxidation divalent Mn^(2+) operando spectroscopies

Two-stage aging treatment to accelerate aging kinetics without impairing strength in B_4C/7A04Al composite

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Science china(Technological Sciences) 2024年第8期67卷 2485-2492页

作者： CHEN YunTao ma GuoNan ZHU ShiZe WANG Dong xiao BoLv ma ZongYi Shi-Changxu Innovation Center for Advanced materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Centre of Excellence for Advanced materials Dongguan 523808China

Aging treatments are the key process to obtain satisfactory strength for 7xxxAl alloys and their composites. However, traditional single-stage(SS) aging is time-consuming to reach a peak strength condition. In this study, an efficient 120℃ + 160℃ two-stage(TS) aging treatment was proposed on a B_4C/7A04Al composite fabricated via powder metallurgy(PM) technology, which could acquire similar peak-aging strength but only took about 15% of the time compared to traditional 120℃ SS aging. The evolution of precipitation during the TS aging was investigated, as well as those of the 7A04Al alloys for comparison. In the second stage aging process, the higher aging temperature accelerated the nucleation of η′ phases inside the grains and thus increased the density of precipitates. Moreover, the short aging time limited the coarsening of precipitates and the broadening of precipitatefree zones. The above factors were beneficial for quickly obtaining satisfactory precipitation strengthening effects. The B_4C/7A04Al composite exhibited slower aging kinetics than the 7A04Al alloy in the TS aging. Mg elements consumption by the chemical reaction between B impurities introduced by B_4C particles and the Al matrix was considered to potentially retard the aging kinetics of the B_4C/7A04Al composite. Nevertheless, the precipitation sequence was not affected.

关键词： aluminum matrix composites aging treatment powder metallurgy mechanical properties precipitation

Alternative technology for the recovery of butyl acetate with low concentration:high capacity adsorbent and high efficiency adsorption

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Green Chemical Engineering 2024年第2期5卷 236-244页

作者： chi ma Lihong Zhao Zhengxin mao Hao Su Qingfen Liu CAS Key Laboratory of Green Process and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing100049China

Industrial pharmaceutical wastewater usually contains butyl acetate(BA)with a concentration of 1 wt%-7 wt%,and the traditional method for BA recovery is distillation with high energy *** method is developed to recover BA with low concentration for the high efficiency and low energy *** polar polyacrylate resins with macroporous structure of 233.1 nm and average particle size of about 526.5μm are successfully synthesized by suspension polymerization and used for the BA adsorption and *** maximum adsorption capacity reaches 171.1 mg g^(-1)with relative standard deviation(RSD)value of 0.2%,which is more than twice the results in the *** BA desorption rate is 97.0%at 100℃with RSD value of 0.4%,and the resins are beneficial to the reuse in the adsorption-desorption *** adsorption thermodynamics and kinetics are investigated,and the BA adsorption is a spontaneous and endothermic process with the increase of disorder *** process is mainly contributed by physical absorption and agree well with Freundlich model and pseudo-first-order adsorption kinetic *** adsorption method avoids boiling a large amount of wastewater and hopefully provides a novel alternative technology for the BA recovery.

关键词： Butyl acetate recovery Resin adsorption Desorption Thermodynamics Kinetics