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Detection and quantification of Pb and Cr in oysters using laser-induced breakdown spectroscopy

Plasma Science and Technology 2023年第4期25卷 195-203页

作者：闫清霞田野李颖林洪贾自文卢渊俞进孙琛白雪石 Vincent DETALLE College of Physics and Optoelectronic Engineering Ocean University of ChinaQingdao 266100People’s Republic of China Food Safety Laboratory Ocean University of ChinaQingdao 266003People’s Republic of China School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Centre de Recherche et de Restauration des Musées de France(C2RMF) Paris 75001France SATIE CY Cergy-Paris UniversitéENS Paris-SaclayCNRS UMR 8029Neuville sur Oise 95031France

The quantitative determination of heavy metals in aquatic products is of great importance for food security issues.Laser-induced breakdown spectroscopy(LIBS)has been used in a variety of foodstuff analysis,but is still limited by its low sensitivity when targeting trace heavy metals.In this work,we compare three sample enrichment methods,namely drying,carbonization,and ashing,for increasing detection sensitivity by LIBS analysis for Pb and Cr in oyster samples.The results demonstrate that carbonization can remove a significant amount of the contributions of organic elements C,H,N and O;meanwhile,the signals of the metallic elements such as Cu,Pb,Sr,Ca,Cr and Mg are enhanced by3–6 times after carbonization,and further enhanced by 5–9 times after ashing.Such enhancement is not only due to the more concentrated metallic elements in the sample compared to the dried ones,but also the unifying of the matter in carbonized and ashed samples from which higher plasma temperature and electron density are observed.This condition favors the detection of trace elements.According to the calibration curves with univariate and multivariate analysis,the ashing method is considered to be the best choice.The limits of detection of the ashing method are 0.52 mg kg-1 for Pb and0.08 mg kg-1 for Cr,which can detect the presence of heavy metals in the oysters exceeding the maximum limits of Pb and Cr required by the Chinese national standard.This method provides a promising application for the heavy metal contamination monitoring in the aquatic product industry.

关键词： laser-induced breakdown spectroscopy(LIBS) heavy metal detection signal enhancement sample preparation method quantification oysters

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Rietveld quantification of γ-C_2S conversion rate supported by synchrotron X-ray diffraction images

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第11期14卷 815-821页

作者： Pi-qi ZHAO Xian-ping LIU Jian-guo WU Pei-ming WANG School of Materials Science and Engineering Tongji University Key Laboratory of Advanced Civil Engineering Materials (Tongji University) Ministry of Education

The pure γ-Ca2SiO4(γ-C2S) phase was prepared at 1623 K of calcining temperature, 10 h of holding time and furnace cooling. The β-C2S phase was obtained through γ-C2S conversion with the following calcination system which was adopted at1473 K of calcining temperature, 1 h of holding time and then water-cooling. The conversion rate of γ-C2S was studied by the Rietveld quantitative laboratory X-ray powder diffraction supported by synchrotron X-ray diffraction images. The refinement results show that the final conversion rate of γ-C2S is higher than 92%. The absolute error of the γ-C2S conversion rate between two Rietveld refinements(sample with or without α-Al2O3) is 3.6%, which shows that the Rietveld quantitative X-ray diffraction analysis is an appropriate and accurate method to quantify the γ-C2S conversion rate.

关键词： γ-C2S β-C2S Rietveld quantification Synchrotron X-ray diffraction image

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Interactions between metal ions and the biopolymer in activated sludge： quantification and effects of system pH value

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Frontiers of Environmental Science & Engineering 2017年第1期11卷 79-87页

作者： Yun Zhou Siqing Xia Binh T. Nguyen Min Long Jiao Zhang Zhiqiang Zhang State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and Engineering Tongji University Shanghai 200092 China Biodesign Swette Center for Environmental Biotechnology Arizona State University Tempe AZ 85287-5701 USA School of Civil Engineering and Transportation Shanghai Urban Construction Vocational College Shanghai 200432 China

The quantification and effects of system pH value on the interactions between Pb（II） and the biopolymer in activated sludge were investigated. The biopolymer had two protein-like fluorescence peaks （Ex/Em = 280 nm1326-338 nm for peak A; Ex/Em = 220-230 nm/324-338 nm for peak B）. The fluorescence intensities of peak B were higher than those of peak A. The fluorophores of both peaks could be largely quenched by Pb（ll）, and the quencher dose for peak B was about half of that for peak A. The modified Stern-Volmer equation well depicted the fluorescence quenching titration. The quenching constant （Ka） values for both peaks decreased with rising system pH value, and then sharply decreased under alkaline conditions. It could be attributed to that the alkaline conditions caused the reduction of available Pb（II） due to the occurrence of Pb（OH）2 sediments. The Ka values of peak B were bigger than those for peak A at the same system pH values. Accordingly, the aromatic proteins （peak B） played a key role in the interactions between metal ions and the biopolymer.

关键词： Metal ions Biopolymer Activated sludge Three-dimensional excitation emission matrix （3D-EEM） Fluorescence regional integration （FRI） technique quantification

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A quantification model for apoptosis in mouse embryos in the early stage of fetation

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Science China(Life Sciences) 2009年第10期52卷 922-927页

作者： WANG PengFei1, FU JianHua1, MA WanYun1, CHEN DieYan1, Lü DanYu2 & BAI WenJia3 1 Key Laboratory for Atomic and Molecular Nanosciences of Education Ministry, Department of Physics, Tsinghua University, Beijing 100084, China 2 Department of Anatomy & Histology and Embryology, School of Basic Medical Sciences Peking University Health Science Center, Beijing 100083, China 3 Department of Automation, Tsinghua University, Beijing 100084, China Key Laboratory for Atomic and Molecular Nanosciences of Education Ministry Department of Physics Tsinghua University Beijing China Department of Anatomy & Histology and Embryology School of Basic Medical Sciences Peking University Health Science Center Beijing China Department of Automation Tsinghua University Beijing China

Apoptosis is the most important inducement and modulator for embryos in the early stage of fetation, i.e. after the 8-cell stage, mostly the morula and blastula stage, to proceed to the stage of nonlinear development. Using a two-photon laser scanning microscopy (TPLSM) system, we obtained 3-dimensional (3D) fluorescent images of preimplantation mouse embryos. A model for quantification was established. The statistical results for the spatial location of apoptosis bodies in embryos was obtained following image processing, as well as investigation of the kinetics of apoptosis. It was found that most (70%) apoptosis occurred in the trophectoderm, and the departure between the centroid and geometric center of embryos had a step transition when embryos developed into the 32-cell stage, which was consistent with the theoretical prediction that the blastocele would induce a symmetry break of the distribution of cells in embryos.

关键词： apoptosis preimplantation mouse embryo TPLSM quantification model

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Uncertainty quantification for stochastic dynamical systems using time-dependent stochastic bases

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Applied Mathematics and Mechanics(English Edition) 2019年第1期40卷 63-84页

作者： Jinchun LAN Qianlong ZHANG Sha WEI Zhike PENG Xinjian DONG Wenming ZHANG State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong University

A novel method based on time-dependent stochastic orthogonal bases for stochastic response surface approximation is proposed to overcome the problem of significant errors in the utilization of the generalized polynomial chaos(GPC) method that approximates the stochastic response by orthogonal polynomials. The accuracy and effectiveness of the method are illustrated by different numerical examples including both linear and nonlinear problems. The results indicate that the proposed method modifies the stochastic bases adaptively, and has a better approximation for the probability density function in contrast to the GPC method.

关键词： uncertainty quantification stochastic response surface approximation timedependent orthogonal bases polynomial chaos

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Value of elastography point quantification in improving the diagnostic accuracy of early diabetic kidney disease

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World Journal of Clinical Cases 2019年第23期7卷 3945-3956页

作者： Qiu-Yun Liu Qi Duan Xiao-Hong Fu Li-Qian Fu Hong-Wei Xia Yong-Lin Wan Department of Ultrasound Naval Military Medical University Affiliated Gongli HospitalShanghai 200135Chi Department of Ultrasound Shanghai Hemujia HospitalShanghai 200336China Department of Nephrology Naval Military Medical University Affiliated Gongli HospitalShanghai 200135China

BACKGROUND Diabetic kidney disease(DKD)is a common complication of diabetes.The patient’s prognosis is poor once DKD progresses to advanced stage.Accurate diagnosis and timely treatment of early DKD are important for improving patient’s prognosis and reducing mortality.AIM To explore the value of elastography point quantification(ElastPQ)in improving the accuracy of early DKD diagnosis.METHODS A total of 69 patients with type 2 diabetes were recruited from Naval Military Medical University Affiliated Gongli Hospital.Patients were divided into early DKD group and medium DKD group according to pathological results and urinary albumin excretion rate(UAER).Another 40 patients with simple diabetes were included as the diabetes group.The baseline data,laboratory diagnostic indicators,and ultrasound indicators for each patient were recorded.The differences of the indicators in the three groups were compared.Multivariate logistic regression was used to analyze the influencing factors of the development from simple diabetes into early DKD and from early DKD into medium DKD.Receiver operating characteristic analyses of potential indicators in identifying early DKD and medium DKD,and early DKD and simple diabetes were established.RESULTS Multivariate logistic regression analysis showed that UAER(P0.9].The accuracy of UAER(AUC=0.744),diabetes duration(AUC=0.757),and renocortical YM(AUC=0.782)for the diagnosis of early DKD and simple diabetes were limited.However,the combined diagnosis of UAER,diabe

关键词： Diabetic kidney disease Elastography point quantification Young's Modulus Urinary albumin excretion rate Combined diagnosis Diabetes

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Cloning of artemisinin biosynthetic cDNAs and novel ESTs and quantification of low temperature-induced gene overexpression

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Science China(Life Sciences) 2008年第3期51卷 232-244页

作者： ZENG QingPing1, ZHAO Chang1, YIN LuLu1, YANG RuiYi1, ZENG XiaoMei1, HUANG Ying2, FENG LiLing3 & YANG XueQin3 1 Laboratory of Biotechnology, Tropical Medicine Institute, Guangzhou University of Chinese Medicine, Guangzhou 510405, China 2 Guangzhou General Hospital, Guangzhou Military Area Command of Chinese PLA, Guangzhou 510010, China 3 Center of Artemisinin Research, Guangzhou University of Chinese Medicine, Guangzhou 510405, China Laboratory of Biotechnology Tropical Medicine Institute Guangzhou University of Chinese Medicine Guangzhou China Guangzhou General Hospital Guangzhou Military Area Command of Chinese PLA Guangzhou China Center of Artemisinin Research Guangzhou University of Chinese Medicine Guangzhou China

To isolate and verify novel genes from qinghao (Artemisia annua) based on the development-specific and environment-induced transcriptomics, leaves have been harvested from the flowering A. annua plants and exposed to low temperature for isolation of total RNAs and cloning of full-length cDNAs and cDNA fragments, or expressed sequence tags (ESTs). After being sequenced and browsed for homol- ogy, these sequences have been submitted to GenBank. Among the accessed 75 sequences, 4 full-length cDNAs are highly homologous to the known A. annua genes, but 71 ESTs are absent in the sequence records of A. annua genes, in which 34 sequences are homologous to other plant genes, including 24 identified protein-coding sequences and 10 unidentified protein-coding sequences, while other 37 sequences are not present in the sequence records of any plant genes, representing the first cloned plant genes. In order to investigate the responsive patterns of A. annua genes to extreme envi- ronmental stresses, especially low temperature, the expression levels of 3 critical qinhaosu (artemisi- nin) biosynthetic genes, ADS, CYP71AV1 and CPR, have been measured in pre- and post-chilling A. annua seedlings cultured in vitro by semi-quantitative PCR (SQ-PCR). Consequently, ADS and CYP71AV1 genes are strongly induced by chilling, but CPR gene is not significantly affected by such treatment. Furthermore, induction of these genes by chilling can be potently suppressed by Ca2+ channel inhibitor LaCl3 or Ca2+ chelator EGTA, suggesting a putative involvement of Ca2+-CaM signal transduction pathway in chilling-induced overexpression of ADS and CYP71AV1 genes. The real-time fluorescent quantitative PCR (RFQ-PCR) assay of A. annua seedlings exposed to chilling has shown that the expression level of CaM gene is up-regulated for more than 2.5 folds, thereby confirming our above inference on the relevance of Ca2+-CaM-mediated signal transduction to chilling-induced gene overexpression. Finally, 7 newly isolated A. annua ESTs have been functionally annot

关键词： Artemisia annua expressed sequence tag (EST) abiotic stress signal transduction fluorescent quantification

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Is 2D stereological method good enough for quantification of solid oxide fuel cell electrode microstructure？

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Science Bulletin 2016年第17期61卷 1313-1316页

作者： Yanxiang Zhang Jingbo Ma Mufu Yan National Key Laboratory for Precision Hot Processing of Metals School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

Nowadays,by the significant progresses in the development of solid oxide fuel cell(SOFC)materials and the thin-film fabrication methods for electrolyte,the performance of SOFC has been dominated by the microstructures of electrodes[1,2].Based on the first generation electrodes consisting of a single phase catalyst,the new generation electrodes consisting of interpenetrating percolating multiple phases with multiple functionalities have been usually employed in commercially-viable SOFCs[3].As

关键词： SOFC quantification viable enough fabrication electrolyte commercially dominated segmented verified

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Monte Carlo light transport-based blood vessel quantification using linear array photoacoustic tomography

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Chinese Optics Letters 2017年第11期15卷 73-77页

作者：蔺祥伟孙明健冯乃章胡德鹏沈毅 Department of Control Science and Engineering Harbin Institute of Technology Harbin 150001 China

Photoacoustic tomography is a noninvasive and nonionized biomedical imaging modality but it cannot reveal the inner structure and sideward boundary information of blood vessels in the linear array detection mode.In contrast,Monte Carlo（MC） light transport could provide the optical fluence distribution around the entire vascular area.This research explores the combination of linear array transducer-based photoacoustic tomography and MC light transport in the blood vessel quantification.Simulation,phantom,and in vivo experiments are in good correlation with the ultrasound imaging,validating this approach can clearly visualize the internal region of blood vessels from background tissue.

关键词： quantification transducer modality visualize noninvasive registered reconstructed clearly compensated artifacts

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quantification of thermal damage in skin tissue

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Journal of Pharmaceutical Analysis 2008年第1期20卷 1-8页

作者：徐峰文婷卢天健 Seffen Keith Engineering Department Cambridge University Cambridge CB 21 PZ U.K. MOE Key Laboratory of Strength and Vibration School of Aerospace Xi'an Jiaotong University

Skin thermal damage or skin burns are the most commonly encountered type of trauma in civilian and military communities. Besides, advances in laser, microwave and similar technologies have led to recent developments of thermal treatments for disease and damage involving skin tissue, where the objective is to induce thermal damage precisely within targeted tissue structures but without affecting the surrounding, healthy tissue. Further, extended pain sensation induced by thermal damage has also brought great problem for burn patients. Thus, it is of great importance to quantify the thermal damage in skin tissue. In this paper, the available models and experimental methods for quantification of thermal damage in skin tissue are discussed.

关键词： skin tissue thermal damage quantification

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