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Determination and ecological risk assessment of arsenic and mercury in sediments from the Changjiang River Estuary and adjacent East China Sea

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Acta Oceanologica Sinica 2021年第4期40卷 32-38页

作者： yu'na Zhang Qianwen Wang Central Laboratory Qingdao Agricultural UniversityQingdao 266109China

Arsenic(As)and mercury(Hg)are pollutants presented in marine environment.A process of atomic fluorescence spectrometry was proposed for the simultaneous determination of As and Hg in marine sediment samples(n=38)collected from the Changjiang River Estuary and adjacent East China *** proposed method used an optimized pretreatment procedure in an aqua regia–H_(2)O digestion *** of As and Hg increased to97%and 98%,respectively,with suitable precisions(2.7%–4.1%)under optimized process *** and Hg were widely presented in these samples,with the ranges of content values were 2.39–8.77μg/g for As and48.03–410.8 ng/g for *** indicate that anthropogenic factors strongly influence the abundances of As and Hg in investigated *** preliminary environmental risk assessment was investigated using the Igeoaccumulation index(Igeo)and anthropogenic contribution rate(M).Findings reveal that Hg demonstrates a strong ecological risk(with average values of 1.3 and 72%for Igeo and M,respectively)in the sediments from the Changjiang River Estuary and adjacent East China ***,Hg should be considered in future investigations.

关键词： arsenic mercury marine sediment spatial distributions ecological risk

Highly Enantioselective Direct Asymmetric Aldol Reaction Catalyzed by 4,5-Methano-L-proline

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Chinese Journal of Chemistry 2015年第10期33卷 171-174页

作者： yukun Zhang Jun Zhu na yu Han yu School of Chemical and Environmental Engineering Shanghai Institute of TechnologyShanghai 201418China College of Biological Chemical Sciences and EngineeringJiaxing UniversityJiaxingZhejiang 314001China

The 4,5-methano-L-proline was used as chiral organocatalysts in direct asymmetric aldol *** the optimal conditions,excellent enantioselectivities(up to 99%ee)were obtained with high chemical yields(up to 95%)for a series of aldehydes using only 5 mol%catalyst *** show the practicality of the method,the reaction was tested at a large *** reaction was complete in 16 h,and the aldol product was obtained in 86%yield and 93%ee.

关键词： asymmetric organocatalysis direct asymmetric aldol reaction 4,5-methano-L-proline

The betaine-dependent remethylation pathway is a homocysteine metabolism pathway associated with the carnivorous feeding habits of spiders

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Insect Science 2022年第4期29卷 1047-1058页

作者： Jingjing Li Fangfang Li na yu Zewen Liu Key laboratory of Integrated Management of Crop Diseases and Pests(Ministry of Education) College of Plant ProtectionNanjing Agricultural UniversityNanjingChina

Homocysteine(Hcy)is a sulfur-containing amino acid derived from the essential amino acid methionine(Met).Circulating levels of Hcy in animals can be increased by feeding on Met-enriched diets,which is generally considered *** are one of the largest groups of obligate carnivores and feed on animals high in protein and *** analyzed the Hcy metabolism pathways in 18 species of 3 taxa(Mammalia,Insecta,and Arachnida)and found that the betaine-dependent remethylation pathway(BRP)was present in all carnivorous arachnid species and mammals but absent in insects and red spider *** then studied the Hcy metabolism pathway in Pardosa *** ***,Hcy is metabolized through the transsulfuration pathway,BRP,and S-methylmethionine-dependent remethylation *** of a prior duplication event of the betaine homocysteine S-methyltransferase(BHMT)gene in the BRP,BHMTa and BHMTb are present in tandem in the genome of *** high expression levels of BHMTa and its high abundance in detoxification tissues indicate that it plays an important role in the BRP;the ability of BHMTa and BHMTb to remethylate Hcy using betaine as substrate was *** with other Hcy metabolic enzyme genes,BHMT responded quickly to the application of Hcy or *** sum,the BRP is important in Hcy metabolism in *** and in other spider species.

关键词： betaine homocysteine S-methy ltransferase homocysteine metabolism Par-dosa pseudonulata spiders

AN ENHANCED ELEMENT-FREE GALERKIN METHOD FOR DYnaMIC RESPONSE OF POROELASTIC SEABED

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Journal of Hydrodynamics 2009年第3期21卷 429-435页

作者： HUA Lei-na yu Xi-ping State Key Laboratory of Hydroscience and Engineering Department of Hydraulic Engineering Tsinghua University Beijing 100084 China

This study presents an effective numerical model for the dynamic response of poroelastic seabed under wave action with enhanced performance. The spatial discretization is based on the Element-Free Galerkin （EFG） method and the time integration based on the GN11 scheme. A stability strategy that adopts a smaller number of nodes for the pore water pressure compared with those for the displacements of the soil skeleton is suggested to resolve the similar difficulty as encountered in the finite element method for a problem with mixed formulation when the pore water is incompressible and the soil skeleton impervious. The accuracy of the numerical model is verified through applying it to a typical case with critical permeability. Good agreement between computational and analytical solutions is obtained.

关键词： poroelastic seabed dynamic response Element-Free Galerkin (EFG) method mixed formulation

ELEMENT-FREE GALERKIN METHOD FOR RESPONSE OF STRATIFIED SEABED UNDER WAVE ACTION

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Journal of Hydrodynamics 2009年第4期21卷 550-556页

作者： HUA Lei-na yu Xi-ping State Key Laboratory of Hydroscience and Engineering Department of Hydraulic Engineering Tsinghua University Beijing 100084 China

A numerical model for the dynamic response of anisotropic and inhomogeneous seabed under wave action is developed based on the element-free Galerkin method for Biot＇s dynamic consolidation equations. Variations of the permeability and the elasticity of the soil in the vertical direction, which is an intrinsic feature of the stratified seabed, are considered. The numerical model is validated under isotropic and homogeneous conditions. The effects of the cross-anisotropy and inhomogeneity on the seabed response and shear failure are found to be remarkable. If the vertical increase of elastic modulus is taken into account, a significant decrease of the depth of shear failure can be expected.

关键词： stratified seabed wave anisotropic inhomogeneous shear failure

Phylogenetic relationship of Podocopida (Ostracoda: Podocopa) based on 18S ribosomal Dna sequences

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Acta Oceanologica Sinica 2006年第2期25卷 99-108页

作者： yu na ZHAO Meiying CHEN Liqiao YANG Pin School of Life Science East China Normal UniversityShanghai 200062China

Nucleotide sequences from 18S rDna of 11 ostracodes, which represent four suborders and six superfamilies of podocopidan, were determined. The phylogenetic relationships were analyzed based on three kinds of methods (maximum-likelihood, maximum-parsimony, and neighbor-joining), and the three topologies gained were basically similar. The results have showed that (1) a monophyletic Podocopida was supported strongly; (2) the phylogenetic relationships of four suborders were (Darwinulocopina plus (Bairdiocopina plus (Cytherocopina plus Cypridocopina))), which indicated that a close relationship between Cytherocopina and Cypridocopina, and Darwinulocopina had separated early from the main podocopinan; (3) Cypridocopinan formed a monophyletic group, among which the phylogenetic relationship of three superfamilies was (Cypridoidea plus (Macrocypridoidea plus Pontocypridoidea)).

关键词： 18S rDna nuclear gene molecular phylogeny Podocopida Ostracoda

Composition control and temperature inferential control of dividing wall column based on model predictive control and PI strategies

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Chinese Journal of Chemical Engineering 2018年第5期26卷 1087-1101页

作者： Jianxin Wang na yu Mengqi Chen Lin Cong Lanyi Sun State Key Laboratory of Heavy Oil Processing College of Chemical Engineering China University of Petroleum (East China) College of Information and Control Engineering China University of Petroleum (East China)

The dividing wall column （DWC） is considered as a major breakthrough in distillation technology and has good prospect of industrialization. Model predictive control （MPC） is an advanced control strategy that has acquired extensive applications in various industries. In this study, MPC is applied to the process for separating ethanol, n-propanol, and n-butanol ternary mixture in a fully thermally coupled DWC. Both composition control and tem- perature inferent/al control are considered. The multiobjective genetic algor/thm function ＂gamult/obj＂ in Matlab is used for the weight tuning of MPC. Comparisons are made between the control performances of MPC and PI strategies. Simulation results show that although both MPC and PI schemes can stabilize the DWC in case of feed disturbances, MPC generally behaves better than the PI strategy for both composition control and tempera- ture inferential control, resulting in a more stable and superior performance with lower values of integral of squared error （ISE）.

关键词： Dividing wall column Composition control Temperature inferential control PI strategy Model predictive control Genetic algorithm

Effect of captopril on serum TNF-α level in acute lung injury rats induced by HCL

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Asian Pacific Journal of Tropical Medicine 2014年第11期7卷 905-908页

作者： Hong-Mei Liu yu-na Guo Tangshang Clinical College of Hebei Medical University Pain Clinics Xuanwu Hospital Capital Medical University

Objective:To observe the effect of captopril on the tumor necrosis factor-α(TNF- α) level and arterial blood gases in acute lung injury(All) induced by HCL in rats,and to analyze its protective ***:Fifty Wistar rats were selected and randomly divided into three groups,with 20 rats in Group Ⅰ and Ⅱ,respectively and 10 animals in Group Ⅲ.ALI model was constructed by intratracheal injection of diluted hydrochloric acid(pH=1.***.1.2 mL/kg).Group Ⅰrats received not any treatment after construction of AM *** Ⅱ rats were treated with captopril(5 mg/kg,i.p.) 5 min after induction of *** Ⅲ served as normal control without any *** minutes after construction of ALI model,all the rats were *** was withdrawn for detection of TNF- α level and arterial blood gases *** lung tissue slices of the three groups were prepared for observation of pathologic histology ***:TNF- α level in serum of Group Ⅰ and Ⅱ rats was significantly higher than that in Group Ⅲ(P<0.05),while TNF- α level in serum of Group Ⅱ was significantly lower in Group Ⅰ(P<0.05).PaCO_2 level was significantly higher(P<0.05),while PaO_2 was significantly lower(P<0.05) in Group Ⅰ and Ⅱ rats than those in Group Ⅲ.PaCO_2 was significantly lower(P<0.05) and PaO_2 was significantly higher(P<0.05) in Group Ⅱ than those in Group Ⅰ.Histological observation showed diffuse congestion and severe edema of luug tissue,obvious thickening and structure damage of alveolar walls and a large amount of neutrophil infiltration in Group Ⅰ *** Ⅱ rats showed mild edema of lung tissue;only a small portion of alveolar walls showed thickening and only a few of neutrophil infiltration could be *** degree of injury was remarkably slighter than that of Group Ⅰ *** Ⅲ rats showed clear lung tissue structure and normal morphology:alveolar walls were uniform and the margin was smooth and few neutrophil could be ***:Captopril can significantly r

关键词： Captopril Acute lung injury TNF-α Lung function

Two new prenylflavonoids from Epimedium sutchuenense

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Chinese Chemical Letters 2009年第7期20卷 842-844页

作者： Chang yuan yu Li na Song Guang Chen College of Life Science and Technology Beijing University of Chemical Technology Beijing 100029 China

Two new prenylflavonoids, named sutchuenmedin A （1） and sutchuenmedin B （2）, were isolated from the 70% EtOH extract of Epimedium sutchuenense. Their structures were determined from spectral analysis. C 2009 Guang... 详细信息

关键词： Epimedium sutchuenense Flavonoids Sutchuenmedin A Sutchuenmedin B