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Meta-analysis of the Occurrence Characteristics and Influencing Factors of Microplastics in Agricultural Soil in China

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huanjing Kexue/Environmental Science 2025年第1期46卷 498-509页

作者： Wu, ting Jiao, Yang-Yang Jiao, Hai-hua School of Life Science Shanxi Normal University Taiyuan 030032 China Department of Life Sciences Changzhi University Changzhi 046011 China Henan Institute of Advanced Technology Zhengzhou University Zhengzhou 450003 China

The potential threat of soil microplastics（MPs，particle sizes smaller than 5 mm）to the agricultural environment and food security production has become a hot issue，but there are few systematic studies on the characteristics and influencing factors of MP pollution in agricultural soil in China. Based on the data of soil MPs and related environmental factors（temperature，precipitation，soil pH，and organic carbon）and social and economic factors（permanent population，gross regional product per capita，gross industrial product per capita，and cultivated land area per capita）extracted from 6 694 samples from 85 published studies from 2020 to 2023，meta-analysis was performed. The characteristics of MPs pollution in agricultural soil and the key factors affecting the accumulation of MPs in soil in six administrative regions of China were analyzed. The results showed that soil MPs had six colors：（semi-）transparent，black，white，yellow，blue，green，and red. There were five kinds of shapes：fragment，fiber，film，particle，and foam. The particle size was between 0.01 and 5.0 mm. There were nine types of MPs：polyethylene（PE），polypropylene（PP），polystyrene（PS），polyester（PES），polyethylene terephthalate（PET），polyvinyl chloride （PVC），rayon（RY），polyacrylonitrile（PAN），and polyamide（PA）. The abundance gradient of soil MPs in different regions was as follows：South-central region > Northwest region > Southwest region > East China region > North China region > Northeast region. The（semi-）transparent（27.6%），fragmented（32.2%），0.01~0.5 mm（66.3%），and PE （37%）types of MPs had the highest detection rates. The characteristics of soil MPs are the result of natural environmental factors（temperature，precipitation，soil pH，organic carbon）and social factors（permanent population，gross regional product per capita，gross industrial product per capita，cultivated land area per capita）. © 2025 Science Press. All rights reserved.

关键词： Polyvinyl chlorides

Stepwise assembly to construct stable copper(I) cluster-based circularly polarized luminescent MOFs

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Science China Chemistry 2025年

作者： Jing-Wen Xie Meng-ting Wang Yan Jin Si Li Jian-hua Qin Shuang-Quan Zang Tomas C.W.Mak College of Chemistry Henan Key Laboratory of Crystalline Molecular Functional Materials Zhengzhou University College of Chemistry and Chemical Engineering Luoyang Normal University Department of Chemistry The Chinese University of Hong Kong

Circularly polarized luminescence （CPL） materials have been extensively studied in recent years owing to their widespread applications in 3D display,optical storage,optical anti-counterfeiting,and biological imaging,***（I） clusters have emerged as a promising candidate for CPL materials,driven by their cost-effectiveness,superior luminescent properties,precise structure,and low ***,the poor environmental stability of copper（I） clusters renders their synthesis and preservation challenging,thereby significantly impeding their ***,we have designed and synthesised a chiral double-coordinated ligand in order to construct copper（I） cluster nodes that can be further *** anticipated,by utilizing stepwise assembly strategy,a Cu4cluster node co-modified by chiral alkynyl ligands and triphenylphosphine was further assembled with Cd2+ions to obtain 2D layers structure,L/*** L/D-Cu4-Cd exhibits excellent stability and optical properties,including bright yellow emission,solvent-responsive luminescence,and CPL activity with a maximum glumup to 2.0×10-3,which shows potential applications in the WLED and *** interestingly,the material also exhibits deflection ability towards different wavelengths of linearly polarized light,showing certain potential in the preparation of circular polarizer.

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不同烫漂方式及冷冻速率对预制西兰花质构品质的影响

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食品科学 2025年第1期46卷 121-130页

作者：赵伊诺金鑫毕金峰谢意通杜婷天津科技大学食品科学与工程学院天津300457 中国农业科学院农产品加工研究所农业农村部农产品加工重点实验室北京100193 沈阳农业大学食品学院辽宁沈阳110866

为探究预制西兰花加工过程中烫漂方式及冷冻速率对西兰花质构品质的影响,对经2种烫漂方式(热水烫漂、蒸汽烫漂)及3种冷冻温度(-20、-40、-80℃)处理的西兰花样品,利用低场核磁共振、理化特性分析方法测定不同处理组样品的水分分布、持... 详细信息

为探究预制西兰花加工过程中烫漂方式及冷冻速率对西兰花质构品质的影响,对经2种烫漂方式(热水烫漂、蒸汽烫漂)及3种冷冻温度(-20、-40、-80℃)处理的西兰花样品,利用低场核磁共振、理化特性分析方法测定不同处理组样品的水分分布、持水性、相对电导率和硬度,观察微观结构。结果表明:维持西兰花硬度的最佳工艺为蒸汽烫漂后进行-40℃冷冻,在此工艺条件下,与对照组相比,处理组西兰花水分分布中结合水峰面积占比(A21)增加最多、持水性最强,花序部分保留66.72%硬度、茎部分保留62.53%硬度,相对电导率增加至87.01%;通过扫描电子显微镜观察发现,经过该处理的西兰花保持了较好的细胞结构。本研究得到了有效维持解冻西兰花质构的工艺,并揭示了不同处理对西兰花水分分布及细胞膜完整性影响的机制,为实际生产过程保持冷冻预制西兰花品质提供了理论与技术支撑。

关键词：预制西兰花持水性水分迁移质构

Iterative parameter estimate with batched binary-valued observations

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Science China(Information Sciences) 2016年第5期59卷 158-175页

作者： Yanlong ZHAO Wenjian bi ting WANG Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of Sciences

In this paper, we consider linear system identification with batched binary-valued *** constructed an iterative parameter estimate algorithm to achieve the maximum likelihood(ML) *** first interesting result was that there exists at most one finite ML solution for this specific maximum likelihood problem, which was induced by the fact that the Hessian matrix of the log-likelihood function was negative definite under binary data and Gaussian system noises. The global concave property and local strongly concave property of the log-likelihood function were obtained. Under mild conditions on the system input, we proved that the ML function has a unique maximum point. The second main result was that the ML estimate was consistent under persistent excitation inputs, which infers the effectiveness of ML estimate. Finally, the proposed iterative estimate algorithm converged to a fixed vector with an exponential rate that was proved by constructing a Lyapunov function. A more interesting result was that the limit of the iterative algorithm achieved the maximization of the ML function. Numerical simulations are illustrated to support the theoretical results obtained in this paper well.

关键词： binary-valued observation maximum likelihood estimate strongly convex system identification exponential rate

Controlling Spiral Waves by Modulations Resonant with the Intrinsic System Mode

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Chinese Physics Letters 2004年第7期21卷 1224-1227页

作者： XIAOJing-hua HUGang HUBam-bi ScienceSchool BeijingUniversityofPostsandTelecommunicationsBeijing100876 DepartmentofPhysics BeijingNormalUniversityBeijing100875 CentreofNonlinearStudiesandDepartmentofPhysics HongKongBaptistUniversityHongKong

We investigate the spiral wave control in the two-dimensional complex Ginzburg–Landau equation. External drivings which are not resonant with spiral waves but with intrinsic system modes are used to successfully annihilate spiral waves and direct the system to various target states. The novel control mechanism is intuitively explained and the richness and flexibility the control results are emphasized.

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微塑料与氯氰菊酯农药复合污染对上海青生长的影响

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陕西科技大学学报 2025年第1期43卷 15-22页

作者：花莉王美婷赵丹洋陕西科技大学环境科学与工程学院陕西西安710021 陕西诺正生物科技有限公司陕西渭南715500

针对微塑料与农药复合污染问题,以上海青(Brassica chinensis L)为供试植物,研究传统微塑料聚乙烯(PE MPs)和可降解微塑料聚乳酸(PLA MPs)单独存在及与氯氰菊酯农药复合作用对植物生长影响的差异.结果显示,PE MPs处理组对上海青生长表... 详细信息

针对微塑料与农药复合污染问题,以上海青(Brassica chinensis L)为供试植物,研究传统微塑料聚乙烯(PE MPs)和可降解微塑料聚乳酸(PLA MPs)单独存在及与氯氰菊酯农药复合作用对植物生长影响的差异.结果显示,PE MPs处理组对上海青生长表现出“低促高抑”的规律.而低添加量PLA MPs处理就会对上海青生长产生抑制作用,且抑制效应随微塑料添加量增加而增加.相比微塑料单独污染,氯氰菊酯农药联合作用对上海青生长的抑制作用影响更显著.PLA MPs对上海青的胁迫作用大于PE MPs,需要对可降解微塑料的环境行为开展进一步评估.

关键词：微塑料氯氰菊酯农药复合污染生物量生理生化指标

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biodistribution and Toxicity Assessment of Superparamagnetic Iron Oxide Nanoparticles In Vitro and In Vivo

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Current Medical Science 2018年第6期38卷 1096-1102页

作者： Qin YU Xiao-qin XIONG Lei ZHAO ting-ting XU Hao bi Rong FU Qian-hua WANG Department of Clinical Laboratory Wuhan Blood CenterWuhan 430000China School of Chemistry and Life Science Hubei University of EducationWuhan 430205China Department of Obstetrics and Gynecology Union HospitalHuazhong University of Science and TechnologyWuhan 430022China

biodistribution and toxicity assessment are critical for safe clinical use of newly developed *** iron oxide nanoparticles (SPION)are effective carriers for targeted drug *** study aimed to examine the toxicity and biodistribution of SPION coated with polyethylenimine (PEI)(SPION-PEI)designed for small interfering RNA (siRNA) delivery both in vitro and in ***-PEI/siRNA complexes were prepared at different weight *** effects of SPION-PEI/siRNA on HSC-T6 cell viability were determined by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT).Rats were divided into three groups:a control group,a normal-saline group and a SPION-PEI/siRNA *** a single intravenous injection,in vivo nanoparticle biodistribution and accumulation were evaluated by Prussian blue staining in the heart,liver,spleen,lung and kidney 8 h,24 h,and 7 days after the *** distribution was histologically studied at the three time points by measuring ironpositive areas (μm2)in organ sections stained with Prussian *** same organs were analyzed by H&E staining for any possible histopathological ***,biochemical indexes such as alanine amino transaminase (ALT),aspartate transaminase (AST),blood urea nitrogen (BUN)and creatinine (CREA)were also assessed at all experimental time *** exhibited that the SPION-PEI could retard siRNA altogether at weight ratios above *** assay showed that SPION-PEI loaded with siRNA had low *** vivo study revealed that the liver and spleen were the major sites of SPION-PEI/siRNA *** iron content was significantly increased in the liver and spleen,peaking 24 h after intravenous injection and then declining *** evidence was found of irreversible histopathological damage to any of the organs *** results suggested that most SPION-PEI/siRNA complexes were distributed in the liver and spleen,which might be the targ

关键词： superparamagnetic iron oxide nanoparticles toxicity biodistribution Prussian blue staining

Radar Target Recognition Algorithm Based on RCS Observation Sequence——Set-Valued Identification Method

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Journal of Systems Science & Complexity 2016年第3期29卷 573-588页

作者： WANG ting bi Wenjian ZHAO Yanlong XUE Wenchao The Key Laboratory of Systems and Control Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of Sciences

This paper studies the problem of radar target recognition based on radar cross section(RCS)observation ***,the authors compute the discrete wavelet transform of RCS observation sequence and extract a valid statistical feature vector containing five *** five components represent five different features of the radar ***,the authors establish a set-valued model to represent the relation between the feature vector and the authenticity of the radar *** set-valued identification method,the authors can estimate the system parameter,based on which the recognition criteria is *** order to illustrate the efficiency of the proposed recognition method,extensive simulations are given finally assuming that the true target is a cone frustum and the RCS of the false target is normally *** results show that the set-valued identification method has a higher recognition rate than the traditional fuzzy classification method and evidential reasoning method.

关键词： Feature extraction radar target recognition RCS set-valued identification wavelet transform.

Temporal and Spatial Variations in the Climate Controls of Vegetation Dynamics on the Tibetan Plateau during 1982–2011

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Advances in Atmospheric Sciences 2018年第11期35卷 1337-1346页

作者： ting hua Xunming WANG Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of Sciences Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity College of Urban and Environmental Science Northwest University Institute of Coastal Research Helmholtz-Zentrum Geesthacht Key Laboratory of Water Cycle & Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences

The ecosystem of the Tibetan Plateau is highly susceptible to climate change. Currently, there is little discussion on the temporal changes in the link between climatic factors and vegetation dynamics in this region under the changing *** employing Normalized Difference Vegetation Index data, the Climatic Research Unit temperature and precipitation data,and the in-situ meteorological observations, we report the temporal and spatial variations in the relationships between the vegetation dynamics and climatic factors on the Plateau over the past three decades. The results show that from the early 1980s to the mid-1990s, vegetation dynamics in the central and southeastern part of the Plateau appears to show a closer relationship with precipitation prior to the growing season than that of temperature. From the mid-1990s, the temperature rise seems to be the key climatic factor correlating vegetation growth in this region. The effects of increasing temperature on vegetation are spatially variable across the Plateau: it has negative impacts on vegetation activity in the southwestern and northeastern part of the Plateau, and positive impacts in the central and southeastern Plateau. In the context of global warming, the changing climate condition(increasing precipitation and significant rising temperature) might be the potential contributor to the shift in the climatic controls on vegetation dynamics in the central and southeastern Plateau.

关键词： vegetation dynamics climate control temporal and spatial variations Tibetan Plateau