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基于固相萃取-高效液相色谱-串联质谱测定孕妇尿液中8种邻苯二甲酸酯代谢物及新生儿出生结局评价

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色谱 2025年第1期43卷 60-67页

作者：王梓皓徐梦菲李贝妮吴萍吴微湖北中医药大学检验学院湖北武汉430065

邻苯二甲酸酯(PAEs)是一种环境内分泌干扰物,广泛存在于日常生活中,并可通过多种途径进入机体。孕妇作为一类特殊人群,若暴露于PAEs,将会对子代的生长发育造成不良影响。研究建立了固相萃取-高效液相色谱-串联质谱(SPE-HPLc-mS/mS)同时... 详细信息

邻苯二甲酸酯(PAEs)是一种环境内分泌干扰物,广泛存在于日常生活中,并可通过多种途径进入机体。孕妇作为一类特殊人群,若暴露于PAEs,将会对子代的生长发育造成不良影响。研究建立了固相萃取-高效液相色谱-串联质谱(SPE-HPLc-mS/mS)同时检测孕妇尿液中8种PAEs代谢物(mPAEs)的分析方法。尿液样品经β-葡萄糖苷酶酶解后,采用Bond Elut Plexa固相萃取柱净化,样品经洗脱、浓缩、复溶后,进行HPLc-mS/mS分析。采用Agilent Eclipse Plus c18色谱柱(100 mm×3 mm,3.5μm)进行分离,以0.1%乙酸水溶液和0.1%乙酸乙腈作为流动相进行梯度洗脱,在多反应监测(mRm)模式下检测,内标法定量。结果表明,8种mPAEs在0.1~200 ng/mL范围内线性关系良好,检出限为0.015~0.048 ng/mL,定量限为0.050~0.160 ng/mL。在低、中、高3个加标水平(1、10、50 ng/mL)下,8种mPAEs的加标回收率为80.2%~99.7%。采用此方法对鄂州市妇幼保健院497名孕妇尿液中的8种mPAEs水平进行检测,结果表明,497名孕妇广泛暴露于PAEs,其中邻苯二甲酸单丁酯(mBP)的含量最高,中位数水平为104.46 ng/mL;邻苯二甲酸单苄酯(mBzP)的含量最低,中位数水平为0.22 ng/mL。同时,研究还对新生儿的出生结局进行了评估,线性回归模型表明,孕妇尿液中的邻苯二甲酸单乙酯(mEP)每增加一个自然对数(ln)水平,孕周减少0.11周(95%置信区间(cI):-0.18~-0.03);孕妇尿液中的邻苯二甲酸(2-乙基-5-氧己基)酯(mEOHP)和邻苯二甲酸单(2-乙基己基)酯(mEcPP)每增加一个ln水平,新生儿出生体重分别降低39.28 g(95%cI:-76.48~-2.09)和39.62 g(95%cI:-73.73~-5.52)。该方法操作简便,检出限低,具有较高的准确度和精密度,通过此方法测定了孕妇尿液中的8种mPAEs,并结合新生儿的出生结局发现,孕期PAEs暴露会影响新生儿的生长发育。

关键词：高效液相色谱-串联质谱邻苯二甲酸酯代谢物孕妇尿液出生结局

Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science china chemistry 2025年第1期68卷 288-296页

作者： Shuai Liu Wen-Qiang Xu Ying-Tong Di man-cheng Tang Ding-Kang chen ming-ming cao Yao-Wen chang Hong-Yu Tang chun-mao Yuan Jun-Bo Yang Zhi-Li Zuo Han Guo Zi-Fei Xu Ying Zeng Yun-Dong wu Xiao-Jiang Hao Key Laboratory of Phytochemistry and Natural medicines (chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of chinese Academy of Sciences Lab of computational chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of microbial metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of medicinal Plants Guizhou Medical University molecular Biology Experimental center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at c-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

关键词： metabolon Diels-Alder reaction semipinacol rearrangement biosynthesis notoamides spiro polycyclic alkaloids

THREE-DImENSIONAL VISUALIZATION OF DEGENERATE FERRITE FORmED BELOW TTT-DIAGRAm BAY IN AN Fe-c-mo ALLOY

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Acta metallurgica Sinica(English Letters) 2003年第3期16卷 169-174页

作者： K.m.wu m.Enomoto Department of materials Science Ibaraki University Nakanarusawa Hitachi 316-8511 Japan

The evolution of degenerate ferrite in an Fe-0.28wt%c-3.0wt%mo alloy isothermally reacted for 10ks at 20℃ below TTT diagram bay temperature have been revealed utilizing serial sectioning in conjunction with computer reconstruction and visualization. The degenerate ferrite is initially formed at prior austenite boundary and then grows toward grain interior rather than along the grain boundary. The degenerate morphology of ferrite may be attributed to repeated nucleation, growth and coalescence of adjacent ferrite crystals. The shape of individual ferrite crystals appears to be rod-like.

关键词： steel phase transformation microstructure ferrite

A Boundary condition-Implemented Immersed Boundary-Lattice Boltzmann method and Its Application for Simulation of Flows Around a circular cylinder

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Advances in Applied mathematics and mechanics 2014年第6期6卷 811-829页

作者： X.Wang c.Shu J.wu L.m.Yang Department of Aerodynamics College of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsYudao StreetNanjing 210016China Department of mechanical Engineering National University of Singapore10 Kent Ridge CrescentSingapore 119260Singapore

A boundary condition-implemented immersed boundary-lattice Boltzmann method(IB-LBm)is presented in this *** present approach is an improvement to the conventional *** the conventional IB-LBm,the no-slip boundary condition is only approximately *** a result,there is flow penetration to the solid *** drawback of conventional IB-LBm is the use of Dirac delta function interpolation,which only has the first order of *** this work,the no-slip boundary condition is directly implemented,and used to correct the velocity at two adjacent mesh points from both sides of the boundary *** velocity correction is made through the second-order polynomial interpolation rather than the first-order delta function ***,the two drawbacks of conventional IB-LBm are removed in the present *** important contribution of this paper is to present a simple way to compute the hydrodynamic forces on the boundary from Newton’s second *** validate the proposed method,the two-dimensional vortex decaying problem and incompressible flow over a circular cylinder are *** shown in the present results,the flow penetration problem is eliminated,and the obtained results compare very well with available data in the literature.

关键词： Immersed boundary method lattice Boltzmann method velocity correction Lagrange interpolation no-slip boundary condition

AdsorbmL: a leap in efficiency for adsorption energy calculations using generalizable machine learning potentials

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npj computational materials 2023年第1期9卷 565-573页

作者： Janice Lan Aini Palizhati muhammed Shuaibi Brandon m.Wood Brook Wander Abhishek Das matt Uyttendaele c.lawrence Zitnick Zachary W.Ulissi Fundamental AI Research(FAIR) Meta AIMetaMenlo ParkCAUSA Department of chemical Engineering Carnegie Mellon UniversityPittsburghPAUSA Scott Institute for Energy Innovation Carnegie Mellon UniversityPittsburghPAUSA

computational catalysis is playing an increasingly significant role in the design of catalysts across a wide range of applications.A common task for many computational methods is the need to accurately compute the adsorption energy for an adsorbate and a catalyst surface of ***,the identification of low-energy adsorbate-surface configurations relies on heuristic methods and researcher *** the desire to perform high-throughput screening increases,it becomes challenging to use heuristics and intuition *** this paper,we demonstrate machine learning potentials can be leveraged to identify low-energy adsorbate-surface configurations more accurately and *** algorithm provides a spectrum of trade-offs between accuracy and efficiency,with one balanced option finding the lowest energy configuration 87.36%of the time,while achieving a~2000×speedup in *** standardize benchmarking,we introduce the Open catalyst Dense dataset containing nearly 1000 diverse surfaces and~100,000 unique configurations.

关键词： adsorption configuration energy

Structures and formation mechanisms of dislocation-induced precipitates in relation to the age-hardening responses of Al-mg-Si alloys

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Journal of materials Science & Technology 2020年第6期41卷 127-138页

作者： Y.X.Lai W.Fan m.J.Yin c.L.wu J.H.chen center for High-Resolution Electron microscopy College of Materials Science&EngineeringHunan UniversityChangsha 410082China Electron microscopy center Shenzhen UniversityShenzhen 518060China

In the slightly deformed Al-mg-Si alloys,dislocation-induced precipitates are frequently observed,and they usually line up,forming sophisticated precipitation *** atomic-resolution electron microscopy in association with hardness measurements,we systematically investigated these precipitates in relation to the age-hardening responses of the *** study reveals that the majority of dislocation-induced complex precipitates are actually short-range ordered while long-range disordered polycrystalline precipitates and multiphase composite precipitates,including polycrystalline U2 precipitates,B’/U2,B’-2/U2,B’/B’-2/U2 and’/U2 composite *** is suggested that the formation of these complex precipitates is mainly owing to a high nucleation rate and rapid growth of different precipitate phases parallel to the associated dislocation *** dislocation-induced precipitates consume more mg than Si from the matrix and have a high formation kinetics,they will have different impacts on the matrix precipitation in different types of Al-mg-Si *** results further demonstrate that for the"normally-β"-hardened"alloy,their formation leads to a coarser precipitate microstructure in the matrix,whereas for the"normally-β’-hardened"alloy,their formation reverses the precipitation pathway in the matrix,resulting in a reduced age-hardening potential of the former alloy and an improved age-hardening potential of the latter alloy.

关键词： Al-mg-Si alloys Precipitation Dislocation Age-hardening Electron microscopy

Anisotropic Inter-granular corrosion Behaviors and microstructures of AlmgSicu Alloy Sheets made by Thermal–mechanical Treatments

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Acta metallurgica Sinica(English Letters) 2022年第2期35卷 275-284页

作者： L.m.Liu Y.X.Lai c.L.wu Z.Zhang J.H.chen center for High-Resolution Electron microscopy College of Materials Science and EngineeringHunan UniversityChangsha 410082China

This study investigates the microstructure and local corrosion behavior of an Al-mg-Si-cu alloy,which has been subjected to cold-rolling with different deformation strain ratios(DSRs)and followed by artificial *** corrosion tests show that peak-aged samples with a small DSR(5-10%)are sensitive to inter-granular corrosion(IGc)along both the normal and rolling *** the DSR increases to medium strength(20-40%),IGc sensitivity decreases along both directions and corrosion propagates *** the DSR is 60-80%,IGc sensitivity along the normal direction continues to decrease,but increases along the rolling direction,indicating pronounced corrosion *** characterization reveals the decreased IGc sensitivity is mainly attributed to a reduction in element segregation at high-angle grain boundaries and the kinked and discontinuous grain boundary corrosion *** increased IGc sensitivity along the rolling direction could be related to the significantly flattened grains.

关键词： Al alloys Local corrosion Anisotropy Transmission electron microscopy(TEm) Electron backscattering diffraction(EBSD)

Review of Networked microgrid Protection:Architectures,challenges,Solutions,and Future Trends

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cSEE Journal of Power and Energy Systems 2024年第2期10卷 448-467页

作者： Jorge de la cruz Ying wu John E.candelo-Becerra Juan c.Vasquez Josep m.Guerrero center for Research on microgrids(cROm) Department of Energy TechnologyAalborg University9220 AalborgDenmark Facultad de minas Departamento de Energia Eléctrica y AutomaticaUniversidad Nacional de ColombiaSede MedellinCarrera 80 No.65-223RobledoMedellin 050041Colombia. center for Research on microgrids at UPc(UPc cROm) Department of Electronic EngineeringTechnical University of Catalonia(UPC)08019 Barcelona Spain IcREA Pg.Lluis Companys 2308010 BarcelonaSpain center for Research on microgrids at AAU(AAU cROm) AAU EnergyAalborg University(AAU)9220 Aalborg EastDenmark

Design and selection of advanced protection schemes have become essential for reliable and secure operation of networked *** protection schemes that allow correct operation of microgrids have been proposed for individual systems in different topologies and ***,protection schemes for networked microgrids are still in devel-opment,and further research is required to design and operate advanced protection in interconnected *** of these microgrids in different nodes with various intercon-nection technologies increases fault occurrence and complicates protection *** paper aims to point out challenges in developing protection for networked microgrids,potential solutions,and research areas that need to be addressed for their ***,this article presents a systematic analysis of different microgrid clusters proposed since 2016,including several architectures of networked microgrids,operation modes,components,and utilization of renewable sources,which have not been widely explored in previous review ***,the paper presents a discussion on protection systems currently available for microgrid clusters,current challenges,and solutions that have been proposed for these ***,it discusses the trend of protection schemes in networked microgrids and presents some conclusions related to ***—Adaptive eprotection,microgrid cluster,microgrid,multiple microgrid,networked microgrid,real-time simulation,smart grid.

关键词： Adaptive eprotection microgrid cluster microgrid multiple microgrid networked microgrid real-time simulation smart grid

Quasi-variable Discount Rates and market Volatility: An Empirical Study

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Journal of Systems Science and Systems Engineering 2023年第5期32卷 515-530页

作者： Pengju Zhao Wei Zhang Xi wu Peter c.coyte Economics and management School Zhongyuan University of TechnologyZhengzhou450007China Economics and management School Tianjin UniversityTianjin300072China Economics and management School System and Industrial Engineering Research CentreZhongyuan University of TechnologyZhengzhou450007China Institute of Health Policy Management and Evaluation(HPME)School of Public HealthUniversity of TorontoTorontoM5R 0A3Canada

This paper proposes an assumption of quasi-variable discount rates to explain the excess volatility puzzle of stock market. Under the assumption, the ARmAX model is derived based on the ccAPm model and cRRA utility function to describe the linear relationship between the discount rate and the consumption growth rate. We conducted empirical research on this model using historical data of the US stock market. The results confirm a significantly negative relationship between consumption growth rate and discount rate. Subsequently, the results of monte carlo simulation show that given the risk preference coefficient and dividend sequence, the rational expectations price fluctuation obtained under the assumption of quasivariable discount rate is the largest.

关键词： Stochastic discount factor market volatility dividend discount model ARmAX