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[Construction of a 17 β-estradiol sensor based on a magnetic graphene oxide/aptamer separating material]

Se pu = Chinese journal of chromatography 2025年第1期43卷 87-95页

作者： Xin-Yu Jin Le-Yuan Chen Ya-Nna Liu wen-Jing Xie Han-Yong Peng State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China. University of Chinese Academy of Sciences Beijing 100049 China. School of Environment Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences Hangzhou 310024 China.

17-Estradiol (E2) is a natural steroidal estrogen essential for a variety of physiological functions in organisms. However, external E2, which is renowned for its potent biological effects, is also considered to be an endocrine-disrupting compound (EDC) capable of disturbing the normal operation of the endocrine system, even at nanogram-per-liter (ng/L) concentrations. Studies have revealed that medical and livestock wastewater can be contaminated with E2, which poses potential risks to human health. Currently, the primary method for detecting E2 relies on liquid chromatography-mass spectrometry, which is limited with regard to on-site or large-scale sample testing due to instrumental constraints. Herein, we developed a magnetic graphene oxide (MGO)/aptamer separating material. The MGO was synthesized by creating a water-in-oil microemulsion at 90 ℃, an agarose hydrogel to load the FeO nanoparticles, and layered graphene oxide (GO). In contrast to conventional methods, such as chemical co-precipitation and solvothermal approaches, this method is more time-efficient and does not require high temperature or pressure. Moreover, the use of a physical encapsulation technique for enwrapping the FeO nanoparticles and layered GO eliminates the need for chemical modification. This approach reduces the use of harmful chemicals, ensures complete loading, and results in highly efficient encapsulation. The MGO was characterized using Fourier-transform infrared (FT-IR) spectroscopy and transmission electron microscopy (TEM), as well as dynamic light scattering (DLS) and Zeta potential analyses, which revealed that the FeO nanoparticles had been successfully loaded onto the GO to produce MGO particles mainly around 5 μm in size. Additionally, this study demonstrated that the aqueous MGO dispersion is highly stable. This substance was used to develop a fluorescent biosensor that uses a "turn-on" mechanism to rapidly and highly sensitively detect E2. MGO is capable of adsorbing a fl

关键词： 17-estradiol (E2) fluorescence biosensor magnetic graphene oxide (MGO) magnetic solid phase separation

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基于HS-SPME-GC-MS解析核桃雄花挥发性成分

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西南大学学报（自然科学版） 2025年第2期47卷 51-60页

作者：王纪辉胡伯凯周雯贵州省核桃研究所/贵州省核桃工程技术研究中心贵阳550005 贵州省公共资源交易中心贵阳550002

检测分析核桃雄花的香气组分种类、相对体积分数,探明核桃雄花的呈香成分及香气特征。以鲜核桃雄花为材料,采用顶空固相微萃取串联气质技术(HS-SPME-GC-MS)对核桃雄花中挥发性成分进行鉴定和定量分析。结果从核桃雄花中共鉴定出22种挥... 详细信息

检测分析核桃雄花的香气组分种类、相对体积分数,探明核桃雄花的呈香成分及香气特征。以鲜核桃雄花为材料,采用顶空固相微萃取串联气质技术(HS-SPME-GC-MS)对核桃雄花中挥发性成分进行鉴定和定量分析。结果从核桃雄花中共鉴定出22种挥发性成分,其中胡桃醌、二甲硫醚2种化合物占总体积分数的62.18%±2.93%、醇类占19.03%±1.91%、烯烃类占10.32%±1.84%、醛类、酮类及酯类化合物占比较低;核桃雄花香气主要由芳樟醇、反松香芹醇、2-甲基丙醛、2-甲基丁醛、3-甲基丁醛、壬醛、十六烷酸乙酯及烯烃类所贡献;主成分分析将22种挥发性化合物归为2类。综合显示:贵州产区核桃雄花香气主要由醇类、醛类和烯烃类成分所构成,种类最为丰富的烯烃类化合物贡献了突出的水果类气味。

关键词：核桃雄花挥发性成分顶空固相微萃取串联气质技术

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High-Order Extended Kalman Filter Design for a Class of Complex Dynamic Systems with Polynomial Nonlinearities

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Chinese Journal of Electronics 2021年第3期30卷 508-515页

作者： SUN Xiaohui wen Chenglin wen Tao School of Automation Hangzhou Dianzi University School of Automation Guangdong University of Petrochemical Technology School of Electronic and Information Engineering Beijing Jiaotong University

A novel High-order extended Kalman Filter(HEKF) is designed for a class of complex dynamic systems with polynomial nonlinearities. The state and measurement models are represented by multidimensional high-order polynomials, respectively. All highorder polynomials in the state model are defined as implicit variables. By combining original variables with implicit variables, the state model is equivalently formulated to be a pseudo-linear form. By modeling dynamic relationship between implicit variables and combining original variables with all implicit variables, a new linear augmented state model is established correspondingly. The measurement model can be equivalently formulated as a linear form. On the basis of the new linear state and linear measurement models, the HEKF is designed and derived in *** results demonstrate the effectiveness of the proposed estimator.

关键词： state estimation implicit variables linear form state model modeling dynamic relationship measurement model nonlinear filters Kalman Filter design polynomials HEKF high-order polynomials combining original variables Kalman filters polynomial nonlinearities measurement models linear state complex dynamic systems pseudolinear form

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Maximum Correntropy High-Order Extended Kalman Filter

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Chinese Journal of Electronics 2022年第1期31卷 190-198页

In this paper, a novel maximum correntropy high-order extended Kalman filter(H-MCEKF) is proposed for a class of nonlinear non-Gaussian systems presented by polynomial form. All high-order polynomial terms in the state model are defined as implicit variables and regarded as parameter variables; the original state model is equivalently formulated into a pseudo-linear form with original variables and parameter variables; the dynamic relationship between each implicit variable and all variables is modeled, then an augmented linear state model appears by combing with pseudo-linear state model; similarly, the nonlinear measurement model can be equivalently rewritten into linear form; once again, the statistical characteristics of non-Gaussian modeling error are described by mean value and variance based on their finite samples; combing original measurement model with predicted value regarded as added state measurement, a cost function to solve the state estimation based on maximum correntropy criterion(MCC) is constructed; on the basis of this cost function, the state estimation problem can be equivalently converted into a recursive solution problem in the form of Kalman filter, in which the filter gain matrix is solved by numerical iteration though its fixed-point equation; illustration examples are presented to demonstrate the effectiveness of the new algorithm.

关键词： cost function filter gain matrix numerical iteration matrix algebra state estimation polynomial form nonlinear measurement nonGaussian modeling error Kalman filters nonGaussian systems sampling methods pseudolinear state model recursive solution problem statistical characteristics state measurement polynomials maximum entropy methods implicit variables high-order polynomial terms H-MCEKF nonlinear filters augmented linear state model MCC pseudolinear form parameter variables maximum correntropy high-order extended Kalman filter fixed-point equation iterative methods maximum correntropy criterion finite samples

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A Novel Step-by-Step High-Order Extended Kalman Filter Design for a Class of Complex Systems with Multiple Basic Multipliers

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Chinese Journal of Electronics 2021年第2期30卷 313-321页

A novel step-by-step linearization high-order Extended Kalman filter SH-EKF is designed for a class of nonlinear systems composed of linear functions and the product of several separable basic functions. The basic functions in the state and measurement models are defined as latent variables; the state and measurement models are equivalently formulated into pseudo-linear models based on the combination of the original variable and the latent variables; latent variables are regarded as new variables,and a dynamic linear model between each latent variable and other latent variables with original state is established;the measurement model is rewritten into the first-order linear product form between the current state and each latent variable; latent variables are solved by Kalman filter step by step, and a stepwise linearized high-order extended Kalman filter is designed. Illustration examples are presented to demonstrate the effectiveness of the new algorithm.

关键词： step-by-step linearization high-order Extended Kalman filter SH-EKF latent variables first-order linear product form multiple basic multipliers Kalman filter step dynamic linear model nonlinear filters measurement model original variable linear functions Kalman filters separable basic functions measurement models Kalman filter design novel step-by-step high-order pseudolinear models

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The Low-Carbon Transition of Energy Systems:A Bibliometric Review from an Engineering Management Perspective

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Engineering 2023年第10期29卷 147-158页

作者： Peng Zhou Yue Lv wen wen School of Economics and Management China University of PetroleumQingdao 266580China

As a major solution to climate change,the low-carbon transition of energy systems has received growing attention in the past *** paper presents a bibliometric review of the literature on the low-carbon transition of energy systems from an engineering management ***,the definition and boundaries of the energy system transition are clarified,covering transformation of the energy structure,decarbonization of fossil fuel utilization,and improvement in energy ***,a systematic search of the related literature and a bibliometric analysis are conducted to reveal the research *** is found that the number of related publications has been growing exponentially during the past decade,with researchers from China,the United Kingdom,the United States,Germany,and the Netherlands comprising the majority of *** studies with interdisciplinary characteristics appear in journals focusing on energy engineering,environmental science,and social science related to energy *** major research themes are identified by clustering the existing literature:(1)low-carbon transition pathways with different spatiotemporal scales and transition constraints;(2)low-carbon technology diffusion with a focus on renewable energy technologies,pollution control technologies,and other technologies facilitating the energy transition;(3)infrastructure network planning for energy systems covering various sectors and regions;and(4)transition-driving mechanisms from the political,economic,social,and natural *** four topics play distinct but mutually supportive roles in facilitating the low-carbon transition of energy systems,and require more in-depth research on designing resilient low-carbon transition pathways with coordinated goals,promoting low-carbon technologies with cost-effective and reliable infrastructure network deployment,and balancing multi-level risks in various ***,business models,nongovernment actors,energy justi

关键词： Low-carbon transition Energy system Bibliometric review Systematic review

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Formation mechanism of interface reaction layer between microporous magnesia refractories and molten steel and its effect on steel cleanliness

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Journal of Iron and Steel Research International 2023年第9期30卷 1743-1754页

作者： wen-wen Zhang Wan Zheng wen Yan Guang-qiang Li The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081HubeiChina Hubei Provincial Key Laboratory for New Process of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan 430081HubeiChina

The ceramic filter in continuous casting tundish can effectively improve the cleanliness of high-performance steel by regulating tundish flow field to promote the removal of inclusions and adsorbing or blocking fine inclusions in the molten steel into the *** interaction between microporous magnesia refractories used as tundish filter and molten interstitial-free(IF)steel at 1873 K was investigated to reveal the formation mechanism of their interface layer and its effect on steel cleanliness by laboratory research and thermodynamic *** results show that the magnesium–aluminum spinel layer at the interface between the molten IF steel and the microporous magnesia refractories is formed mainly by the reaction of MgO in the refractory with the[Al]and[O]in the molten steel,significantly reducing the total O content,the size and amount of inclusions of the molten *** addition,the interparticle phases of microporous magnesia refractories at high temperature can adsorb Al_(2)O_(3) and TiO_(2) inclusions in the molten steel into interparticle channels of the refractories to form high melting point spinel,impeding the further penetration of the molten *** a result,the consecutive interface layer of high melting point spinel between microporous magnesia refractories and molten steel can improve the cleanliness of the molten steel by adsorbing inclusions in the molten steel and avoid the direct dissolution of refractories of the tundish ceramic filter immersed in the molten steel,increasing their service life.

关键词： Tundish metallurgy Microporous magnesia refractory Interstitial-free steel Formation mechanism Interface reaction layer Inclusion removal

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基于地理分区的陕北黄土高原生态系统服务权衡/协同的尺度效应研究

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水土保持研究 2025年第1期32卷 305-315页

作者：温昕王继军韩晓佳中国科学院水土保持与生态环境研究中心中国科学院水利部水土保持研究所中国科学院大学西北农林科技大学水土保持研究所中国科学院生态环境研究中心

[目的]明晰生态系统服务的权衡/协同关系，保证生态系统服务长期有效供应，实现流域生态保护与高质量发展。[方法]以典型退耕区陕北黄土高原为例，利用1990—2020年土地利用变化数据，基于InVEST模型量化4种关键生态系统服务即碳储量、... 详细信息

[目的]明晰生态系统服务的权衡/协同关系，保证生态系统服务长期有效供应，实现流域生态保护与高质量发展。[方法]以典型退耕区陕北黄土高原为例，利用1990—2020年土地利用变化数据，基于InVEST模型量化4种关键生态系统服务即碳储量、产水量、土壤保持量和生境质量的时空分布特征，通过相关性分析探讨了各类生态系统服务间的权衡/协同关系和呈现的尺度特征。[结果](1) 1990—2020年碳储量和生境质量处于不断增加的趋势，产水量和土壤保持量呈现先降低后增加总体增加的趋势，空间上呈东南略低西北略高的分布。(2)陕北黄土高原生态系统服务以协同作用为主，且在1990—2020年协同效应不断增强，权衡作用主要发生在产水量与其他生态系统服务之间，权衡作用的区域主要分布在研究区西部和东北部地区。(3)生态系统服务间的权衡/协同作用存在着空间尺度效应，随着空间尺度的增加，相关性逐渐增强而显著性有所下降，且作用关系的方向性会发生改变。[结论]陕北黄土高原生态系统服务以协同为主，生态系统服务间的权衡/协同作用存在着空间尺度效应。

关键词：生态系统服务权衡/协同作用尺度效应地理分区陕北黄土高原

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一种基于柱面镜聚焦系统的高灵敏度全谱光谱仪

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光谱学与光谱分析 2025年第1期45卷 222-230页

作者：陈吉文陈作儿赵迎北方工业大学电气与控制工程学院北京100144

很多元素的最灵敏谱线主要分布在紫外波段。一些常被作为检测对象的重要元素,例如C、P和S,其谱线甚至位于200 nm以下的真空紫外波段。然而真空紫外波段内的辐射极易受空气吸收而无法在空气中传输。因此为了适用于紫外波段各谱线的检测,... 详细信息

很多元素的最灵敏谱线主要分布在紫外波段。一些常被作为检测对象的重要元素,例如C、P和S,其谱线甚至位于200 nm以下的真空紫外波段。然而真空紫外波段内的辐射极易受空气吸收而无法在空气中传输。因此为了适用于紫外波段各谱线的检测,常使用光程短、系统精简的罗兰圆光学系统作为光谱仪的色散系统,并且在进行检测分析时,还需对设备腔体内部建立相对真空的环境进行实验,进而减小实验环境对真空紫外波段内各谱线强度的削弱作用。然而即使在该条件下,P和S这两种元素在真空紫外波段的谱线灵敏度仍然较弱。为此为了实现真空紫外波段范围内的高灵敏度,本研究在距离像面前30 mm处位置设计了一个柱面镜聚焦系统。其采用了材料为CaF_(2)、中心厚度为5 mm以及弧矢面曲率半径为22.06 mm的柱面镜作为核心部件。并利用仿真软件Zemax对设计的光学系统进行仿真与优化,以及从非序列模式下的辐射照度仿真结果可知,柱面镜聚焦系统在几乎不影响分辨率的情况下对各波长成像灵敏度有较大的提升。最后以中低合金钢为检测样品,使用电火花激发光源对样品中各元素在紫外波段内的各谱线进行激发,进而验证光谱仪的各项性能:通过一次拟合、参比拟合以及二次拟合,建立每个元素谱峰强度和实际含量之间的数学模型,并算得各元素的拟合优度R^(2)均在0.99以上;柱面镜聚焦系统显著提高了设备在真空紫外波段的灵敏度,响应提高了1倍以上。实验结果表明,柱面镜聚焦系统的设计方法对于提升罗兰圆色散系统的灵敏度具有一定的参考价值。

关键词：紫外光谱罗兰圆光学系统柱面镜灵敏度拟合优度

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Caution in building a Burgers circuit for studying secondary dislocations

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Journal of Materials Science & Technology 2019年第6期35卷 1192-1197页

作者： wen-Sheng Xu wen-Zheng Zhang Key Laboratory of Advanced Materials (MOE) School of Materials Science and EngineeringTsinghua University

As the Burgers vector of a secondary dislocation may not conform to the translation vectors in the periodic pattern in a high-resolution transmission electron microscope(HRTEM) image, a Burgers circuit directly constructed according to an HRTEM image may render a wrong Burgers vector. The HRTEM images of the habit plane(HP) of δ precipitate in an Inconel 718 alloy were re-examined by using different Burgers circuits, as an example. Evidence is found for predicted secondary dislocation associated with a down step. The Burgers vector of the dislocation is 1/6[112]/1/3[001]δ, determined with the Burgers circuit built on the reference of the displacement shift completely lattice(DSCL). It is consistent with both the calculated and the measured result of the major defects in the habit plane. Different Burgers vectors due to different Burgers circuits were explained quantitatively. The present study has a general implication for the determination of the Burgers vectors of secondary interfacial dislocations in other systems.

关键词： Dislocation Burgers vector Burgers circuit Coincidence site lattice (CSL) Displacement shift completely lattice (DSCL) Lattice correspondence

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