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[Determination of eight phthalate metabolites in urine of pregnant women and evaluation of neonatal birth outcomes based on solid-phase extraction-high performance liquid chromatography-tandem mass spectrometry]

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Se pu = Chinese journal of chromatography 2025年第1期43卷 60-67页

作者： Zi-hao Wang Meng-Fei xu Bei-Ni Li Ping wu Wei wu hubei University of Chinese Medicine Wuhan 430065 China.

Phthalates (PAEs) are endocrine-disrupting chemicals that are widely present in everyday life and enter the human body through various pathways. The release of PAEs into the environment through pathways that include leaching, evaporation, abrasion, and the use of personal care products exposes humans to PAEs via ingestion, inhalation, and dermal absorption. Pregnant women, as a particularly vulnerable population, risk adverse newborn growth and development when exposed to PAEs. While the concentrations of PAEs in urine reflect recent exposure levels in humans, urinary levels of phthalate metabolites (mPAEs) are commonly used as biomarkers of internal exposure owing to the relatively short biological half-lives of PAEs (h). In this study, we developed a solid-phase extraction-high performance liquid chromatography-tandem mass spectrometry (SPE-hPLC-MS/MS) method for simultaneously detecting eight mPAEs in the urine of pregnant women. Urine samples were enzymatically hydrolyzed with -glucosidase and then purified using the Bond Elut Plexa SPE column, with subsequent elution, concentration, and redissolved performed prior to hPLC-MS/MS. Separation was achieved using an Agilent Eclipse Plus C18 column (100 mm×3 mm, 3.5 μm), with gradient elution performed using 0.1% acetic acid aqueous solution and 0.1% acetic acid acetonitrile as mobile phases. Multiple reaction monitoring (MRM) mode was used for detection, with quantification performed using the internal-standard method. Good linearities were obtained in the range of 0.1-200 ng/mL for the eight mPAEs, with limits of detection (LODs) and quantification (LOQs) of 0.015-0.048 and 0.050-0.160 ng/mL, respectively. The eight mPAEs exhibited recoveries of 80.2%-99.7% at three spiked levels (1, 10, and 50 ng/mL). This method was subsequently used to analyze the eight mPAEs levels in urine samples of 497 pregnant women from the Ezhou Maternity and Child health Care hospital. The participants exhibited widespread exposure t

关键词： birth outcomes high performance liquid chromatography-tandem mass spectrometry (hPLC-MS/MS) phthalate metabolites (mPAEs) urine samples of pregnant women

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A novel twice-interpolation finite element method for solid mechanics problems

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Acta Mechanica Sinica 2010年第2期26卷 265-278页

作者： C. Zheng S. C. wu x. h. Tang J. h. Zhang State Key Laboratory of hydraulics and Mountain River Engineering Sichuan University 610065 Chengdu China State Key Laboratory of Digital Manufacturing and Equipment Technology Huazhong University of Science and Technology 430074 Wuhan China Department of Mechanical Engineering Centre for Advanced Computations in Engineering Science (ACES)National University of Singapore Singapore 117576 Singapore

Formulation and numerical evaluation of a novel twice-interpolation finite element method （TFEM） is presented for solid mechanics problems. In this method, the trial function for Galerkin weak form is constructed through two stages of consecutive interpolation. The primary interpolation follows exactly the same procedure of standard FEM and is further reproduced according to both nodal values and averaged nodal gradients obtained from primary interpolation. The trial functions thus constructed have continuous nodal gradients and contain higher order polynomial without increasing total freedoms. Several benchmark examples and a real dam problem are used to examine the TFEM in terms of accuracy and convergence. Compared with standard FEM, TFEM can achieve significantly better accuracy and higher convergence rate, and the continuous nodal stress can be obtained without any smoothing operation. It is also found that TFEM is insensitive to the quality of the elemental mesh. In addition, the present TFEM can treat the incompressible material without any modification.

关键词： Twice-interpolation finite element method·Stress smoothing Volumetric locking Mesh distortion

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A novel mesh-free poly-cell Galerkin method

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Acta Mechanica Sinica 2009年第4期25卷 517-527页

作者： C. Zheng x. h. Tang J. h. Zhang S. C. wu State Key Laboratory of hydraulics and Mountain River Engineering Sichuan University State Key Laboratory of Digital Manufacturing and Equipment Technology Huazhong University of Science and Technology Centre for Advanced Computations in Engineering Science (ACES) Department of Mechanical EngineeringNational University of Singapore

A novel numerical method is explored and named as mesh-free poly-cell Galerkin method. An improved moving least-square （MLS） scheme is presented, which can avoid the matrix inversion in standard MLS and can be used to construct shape functions possessing delta Kronecher property. A new type of local support is introduced to ensure the alignment of integral domains with the cells of the back-ground mesh, which will reduce the difficult in integration. An intensive numerical study is conducted to test the accuracy of the present method. It is observed that solutions with good accuracy can be obtained with the present method.

关键词： MPG CO-MSL Mesh-free Meshless Voronoi diagram

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Effect of solute atom concentration and precipitates on serrated flow in Mg-3Nd-Zn alloy

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Journal of Materials Science & Technology 2018年第7期34卷 1236-1242页

作者： W.h.Wang D.wu R.S.Chen x.N.Zhang State Key Laboratory of Metal Matrix Composites School of Materials Science and Engineering Shanghai Jiao Tong University The Group of Magnesium Alloys and Their Applications Institute of Metal Research Chinese Academy of Sciences

Influence of solute atom concentration and precipitates on serrated flow, i.e., Portevin-Le Chatelier effect, was studied in Mg-3Nd-Zn alloy by tensile test at 250℃ with a strain rate of l x 10^-3 s^-1 Microstructure and tensile property of the Mg-3Nd-Zn alloy in solution and aging conditions were also investigated. Results indicate that the serrated flow was weakened with aging time, and geometry of the serrations changed from sharp to rounded corner. Through analyzing the mechanism of the interactions between dislocations and solute atoms, it was identified that the precipitates did not only weaken the serrated flow due to the decrease in the concentration of solute atom, but also regulate the serration type by restraining the movement of dislocations during high temperature deformation.2017 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science ＆ Technology.

关键词： Magnesium alloy Serrated flow Precipitate heat treatment Deformation behavior

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The cGAS-STING-interferon regulatory factor 7 pathway regulates neuroinflammation in Parkinson's disease

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Neural Regeneration Research 2025年第8期20卷 2361-2372页

作者： Shengyang Zhou Ting Li Wei Zhang Jian wu hui hong Wei Quan xinyu Qiao Chun Cui Chenmeng Qiao Weijiang Zhao Yanqin Shen Laboratory of Neurodegenerative and Neuroinjury Diseases Wuxi Medicine SchoolJiangnan UniversityWuxiJiangsu ProvinceChina

Interferon regulatory factor 7 plays a crucial role in the innate immune ***,whether interferon regulatory factor 7-mediated signaling contributes to Parkinson's disease remains *** we report that interferon regulatory factor 7 is markedly up-regulated in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced mouse model of Parkinson's disease and co-localizes with microglial *** the selective cyclic guanosine monophosphate adenosine monophosphate synthase inhibitor RU.521 and the stimulator of interferon genes inhibitor h151 effectively suppressed interferon regulatory factor 7 activation in BV2 microglia exposed to 1-methyl-4-phenylpyridinium and inhibited transformation of mouse BV2 microglia into the neurotoxic M1 *** addition,si RNA-mediated knockdown of interferon regulatory factor 7 expression in BV2 microglia reduced the expression of inducible nitric oxide synthase,tumor necrosis factorα,CD16,CD32,and CD86 and increased the expression of the anti-inflammatory markers ARG1 and *** together,our findings indicate that the cyclic guanosine monophosphate adenosine monophosphate synthase-stimulator of interferon genes-interferon regulatory factor 7 pathway plays a crucial role in the pathogenesis of Parkinson's disease.

关键词： cyclic guanosine monophosphate adenosine monophosphate synthase h151 interferon regulatory factor 7 M1 phenotype neurodegenerative disease neuroinflammation Parkinson’s disease RU521 STING type I interferon

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Deformation behavior of Mg-Y-Ni alloys containing different volume fraction of LPSO phase during tension and compression through in-situ synchrotron diffraction

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Journal of Magnesium and Alloys 2024年第9期12卷 3631-3645页

作者： S.Z.wu Y.Q.Chi G.Garces x.h.Zhou h.G.Brokmeier x.G.Qiao M.Y.Zheng School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China School of Electromechanical Engineering Guangdong University of TechnologyGuangzhou 510006China Department of Physical Metallurgy CENIM-CSICAvenida Gregorio del Amo 828040 MadridSpain Institute of Materials Science and Engineering Clausthal University of TechnologyAgricolastrasse 6D-38678 Clausthal-ZellerfeldGermany

The deformation behavior of the as-extruded Mg-Y-Ni alloys with different volume fraction of long period stacking ordered(LPSO)phase during tension and compression was investigated by in-situ synchrotron *** micro-yielding,macro-yielding,tension-compression asymmetry and strain hardening behavior of the alloys were explored by combining with deformation *** micro-yielding is dominated by basal slip of dynamic recrystallized(DRxed)grains in tension,while it is dominated by extension twinning of non-dynamic recrystallized(non-DRxed)grains in *** macro-yielding,the non-DRxed grains are still elastic deformed in tension and the basal slip of DRxed grains in compression are ***,the LPSO phase still retains elastic deformation,but can bear more load,so the higher the volume fraction of hard LPSO phase,the higher the tensile/compressive macro-yield strength of the *** from the low volume fraction of the non-DRxed grains and the delay effect of LPSO andγphases on extension twinning,the as-extruded alloys exhibit excellent tension-compression *** the volume fraction of LPSO phase reaches∼50%,tension-compression asymmetry is reversed,which is due to the fact that the LPSO phase is stronger in compression than in *** tensile strain hardening behavior is dominated by dislocation slip,while the dominate mechanism for compressive strain hardening changes from twinning in theα-Mg grains to kinking of the LPSO phase with increasing volume fraction of LPSO *** activation of kinking leads to the constant compressive strain hardening rate of∼2500 MPa,which is significantly higher than the tensile strain hardening rate.

关键词： Mg-Y-Ni alloys LPSO phase In-situ synchrotron diffraction Micro-yielding Tensile-compression asymmetry Strain hardening

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Tailor-made high elasticity and low-hysteresis hydrogels based on asymmetric h-bonding crosslinking for wearable applications

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Science China Chemistry 2025年

作者： xiaofang Shi Nan Shi Miaomiao Dang Chengyu Ji Yingjie Li Peiyi wu Zhiguo hu Collaborative Innovation Centre of henan Province for Green Manufacturing of Fine Chemicals Henan Engineering Laboratory of Chemical Pharmaceutical and Biomedical Materials School of Chemistry and Chemical Engineering Henan Normal University State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Chemistry Chemical Engineering and Biotechnology & Center for Advanced Low-dimension Materials Donghua University

The conventional method of fabricating hydrogels constantly confronts the conflict between elasticity and toughness, limiting their repetitive application. Achieving the desired elasticity through a simple and low-cost approach is a significant challenge for hydrogels, particularly through rational molecular design. here, low-hysteresis and high-toughness hydrogels are developed from the design of a new feature monomer, N-acryloylethylsemicarbazide (NACE). Based on a concept of “asymmetric hbonding design”, the unique double and triple h-bonding of NACE can result in a novel asymmetric crosslinking polymer with alternating strong and weak h-bonding regions. The NACE is copolymerized with acrylamide (AM) to regulate the mechanical properties of hydrogel via h-bonding density. The P(NACE-AM) ionic hydrogels are obtained simply and rapidly via one-step photopolymerization without a chemical cross-linking agent. The P(NACE-AM) hydrogels combine superb mechanical elasticity and toughness, and excellent ionic conductivity, showing great potential as durable ionic conductive devices for wearable utilization.

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EFFECT OF COPPER ADDITION ON MEChANICAL PROPERTIES OF 4Cr16Mo

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Acta Metallurgica Sinica(English Letters) 2008年第1期21卷 43-49页

作者： h.M. Geng x.C. wu Y.A. Min h.B. Wang h.K. Zhang College of Materials Science and Engineering Shanghai University Shanghai 200072 China Special Steel Branch Baoshan Iron ＆ Steel Co Ltd Shanghai 200940 China

Experiments conducted to determine the effect of copper addition on the machinability of plastic mold steel, 4Cr16Mo, were presented. The machinability of mold steel 4Cr16Mo was visibly improved by adding Cu. The top wear of 4Cr16Mo with copper was less than that without copper. The Cu-rich phase had the effect of a lubricant and the heat conductivity, which reduced cutting-tool wear, improved machinability, and increased the service life of the cutting-tool. Increasing of copper addition decreased the hot-working character of 4Cr16Mo. The optimal hot-working parameters for 4Cr16Mo with copper were determined by the tensile test and the compression test. The rate of deformation should be adopted as 0.6 s-1. The heating-up temperature, initial forging temperature, and terminal forging temperature were 1200℃, 1150℃, and 950℃, respectively.

关键词： Machinability Cutting-tool hot-shortness Cu-rich phase

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Reactive destabilization and bidirectional catalyzation for reversible hydrogen storage of LiBh_(4) by novel waxberry-like nano-additive assembled from ultrafine Fe_(3)O_(4) particles

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Journal of Materials Science & Technology 2024年第6期173卷 63-71页

作者： S.Wang M.h.wu Y.Y.Zhu Z.L.Li Y.x.Yang Y.Z.Li h.F.Liu M.x.Gao Department of Material Science Shenzhen MSU-BIT UniversityShenzhen 518172China State Key Laboratory of Silicon and Advanced Semiconductor Materials&School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027China Institute of Resources Utilization and Rare Earth Development State Key Laboratory of Rare Metals Separation and Comprehensive UtilizationGuangdong Provincial Key Laboratory of Rare Earth Development and ApplicationGuangdong Academy of SciencesGuangzhou 510650China Institute of Science and Technology for New Energy Xi’an Technological UniversityXi’an 710021China National Supercomputing Center in Shenzhen Shenzhen 518055China

LiBh_(4) containing 18.5 wt.%h_(2) is an attractive high-capacity hydrogen storage material,however,it suffers from high operation temperature and poor ***,a novel and low-cost bifunctional additive,waxberry-like Fe_(3)O_(4) secondary nanospheres assembled from ultrafine primary Fe_(3)O_(4) nanoparticles,is synthesized,which exhibits significant destabilization and bidirectional catalyzation towards(de)hydrogenation of LiBh_(4).With an optimized addition of 30 wt.% waxberry-like Fe_(3)O_(4),the system initiated dehydrogenation below 100℃ and released a total of 8.1 wt.%h_(2) to 400℃.After 10 cycles,a capacity retention of 70% was achieved,greatly superior to previously reported oxides-modified *** destabilizing and catalyzing mechanisms of waxberry-like Fe_(3)O_(4) on LiBh_(4) were systematically analyzed by phase and microstructural evolutions during dehydrogenation and hydrogenation cycling as well as density functional theory(DFT)*** present work provides new insights in developing advanced nano-additives with unique structural and multifunctional designs towards LiBh4 hydrogen storage.

关键词： LiBh_(4) hydrogen storage Waxberry-like Fe_(3)O_(4) Destabilization Catalysis

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SIMULATION OF VIBRATION STRESS RELIEF AFTER WELDING BASED ON FEM

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Acta Metallurgica Sinica(English Letters) 2008年第4期21卷 289-294页

作者： x.C. Zhao Y.D. Zhang h.W. Zhang Q. wu School of Mechanical Engineering and Automation Beijing University of Aeronautics and Astronautics Beijing 100083 China State Key Laboratory of Virtual Reality Technology Beijing University of Aeronautics and AstronauticsBeijing 100083 China

A finite element model is developed for the simulation of vibration stress relief （VSR） after welding. For the nonresonant vibration, the reduction in stress strongly depends on the amplitude of vibration. For the resonant vibration, the vibration frequency is the key for stress relief. The vibration frequency should be close to the structure natural frequency for the desired vibration mode. Only small vibration amplitude is required, which will be amplified during vibration. Vibration time does not have a major impact on vibration stress relief. When the amplitude of vibration stress relief is large, the treatment will be more effective.

关键词： Residual stress Vibration stress relief Simulation

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