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Intraspecific differences in effects of co-contamination of cadmium and arsenate on early seedling growth and metal uptake by wheat

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Journal of Environmental Sciences 2007年第10期19卷 1221-1227页

作者： LIU Xiao-li ZHANG shu-zhen State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

A hydroponic experiment was carried out to study intraspecific differences in the effects of different concentrations of cadmium （Cd）（0-10 mg/L） and arsenate （As（V））（0-8 mg/L） on the growth parameters and accumulation of Cd and As in six wheat varieties Jing- 9428, Duokang- 1, Jingdong- 11, Jing-411, Jingdong-8 and Zhongrnai-8. The endpoints of wheat seedlings, including seed germination, biomass, root length and shoot height, decreased with increasing the Cd and As concentrations. Significant differences in seed germination, biomass, root length, shoot height and the accumulation of Cd and As were observed between the treatments and among the varieties （p 〈 0.05）. The lethal dosage 50% were about 20, 80, 60, 60, 80 and 20 mg As/L for Jing-9428, Duokang-1, Jingdong-11, Jing-411, Jingdong-8 and Zhongrnai-8, respectively, and the corresponding values for Cd were about 30, 80, 20, 40, 60 and 10 mg Cd/L, respectively. Among the six varieties, Duokang-1 was found to be the most resistant to Cd and As toxicity, and Zhongrnai-8 was the most sensitive to Cd and As co-contamination. The resistance of the six varieties was found dependant on the seedling uptake of Cd and As. Duokang-1 was the most suitable for cultivation in Cd and As co-contaminated soils.

关键词： Cd As varieties co-contamination wheat seedling

Geometrical Evaluation on the Viscous Effect of Point-Absorber Wave-Energy Converters

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China Ocean Engineering 2018年第4期32卷 443-452页

作者： CHEN Zhong-fei ZHOU Bin-zhen ZHANG liang ZHANG Wan-chao WANG shu-qi ZANG Jun College of Shipbuilding Engineering Harbin Engineering University School of naval structure and ocean engineering Jiangsu University of Science and Technology Department of Civil and Architecture Engineering University of Bath

The fluid viscosity is known to have a significant effect on the hydrodynamic characteristics which are linked to the power conversion ability of the wave energy converter(WEC). To overcome the disadvantages of case-by-case study through the experiments and numerical computations employed by the former researches, the viscous effect is studied comprehensively for multiple geometries in the present paper. The viscous effect is expressed as the viscous added mass and damping solved by the free-decay method. The computational fluid dynamics(CFD) method is employed for the calculation of the motion and flow field around the floater. The diameter to draft ratio and bottom shape are considered for the geometrical evaluation on the viscous effect. The results show that a slenderer floater presents a stronger viscous effect. Through the comparisons of the floaters with four different bottom shapes, the conical bottom is recommended in terms of low viscous effect and simple geometry for manufacture. A viscous correction formula for a series of cylindrical floaters is put forward, for the first time, to help the engineering design of outer-floaters of point-absorber WECs.

关键词： viscous effect wave energy convertor multiple geometries viscous correction CFD

Micro RNA-378a-3p Downregulation as a Novel Biomarker with Poor Clinical Outcomes in Cervical Cancer

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Biomedical and Environmental Sciences 2021年第3期34卷 213-221页

作者： ZHANG liang WU zhen An Department of Clinical Laboratory Medicine Beijing Hospital of Integrated Chinese and Western MedicineBeijing 100039China

Objective Cervical cancer(CC)is one of the most common malignant tumors in *** study aimed to investigate the prognostic significance of serum micro RNA(mi R)-378 a-3 p in CC and the effect of mi R-378 a-3 p on tumor *** Real-time quantitative polymerase chain reaction analysis was used to measure the expression of mi R-378 a-3 p in serum from patients with CC and healthy control subjects as well as from CC tissues and adjacent normal *** association between serum mi R-378 a-3 p levels and clinicopathological factors was *** correlation between mi R-378 a-3 p levels and overall survival(OS)of CC patients was determined by Kaplan-Meier *** CC cell proliferation and migration abilities after transfection of mi R-378 a-3 p mimics were detected by Cell Counting Kit-8 and scratch wound healing assays,*** volume and weight in mice treated with mi R-378 a-3 p were measured using a caliper and an electronic *** Mi R-378 a-3 p expression was downregulated in the serum and tissues of CC patients compared to that in healthy control subjects and normal tissues,*** expression of mi R-378 a-3 p was positively correlated with large tumor size,advanced tumor stage,and lymph node *** OS of patients with low expression of mi R-378 a-3 p was significantly lower than that of patients with high *** of mi R-378 a-3 p suppressed the proliferation and migration of CC *** vivo studies indicated that overexpression of mi R-378 a-3 p was associated with decreased tumor volume and weight in *** Mi R-378 a-3 p downregulation is associated with the development and prognosis of CC,suggesting that it may be a potential biomarker for CC.

关键词： Cervical cancer miR-378a-3p Biomarker Prognosis Tumor growth

Highly Site-and Enantioselective N-H Functionalization of N-Monosubstituted Aniline Derivatives Affording Pyrazolones Bearing a Quaternary Stereocenter

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Chinese Journal of Chemistry 2022年第10期40卷 1144-1148页

作者： Guan-Jun Wang shu-Yu Zhang zhen-liang Sun Peng Li Tong-Mei Ding School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240China Southern Medical University Affiliated Fengxian Hospital Shanghai 201499China State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoMacao 999078China

Chiral phosphoric acid catalyzed the regio-and enantioselective N-H functionalization of N-alkylaniline with pyrazolones derived ketimines as electrophiles,providing a variety of chiral pyrazolones containing a tetrasubstituted stereocenter bearing a new N,N'-acetal motif in excellent yields and high *** strategy was featured by low catalyst loading,mild conditions,and high efficiency and selectivity.

关键词： Asymmetric synthesis Enantioselectivity Alkylation Nitrogen heterocycles Quaternary stereocenter

Enhanced electrochemical properties of LaFeO_3 with Ni modification for MH–Ni batteries

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International Journal of Minerals,Metallurgy and Materials 2018年第10期25卷 1201-1207页

作者： zhen-tao Dong Yuan Li Kai-liang Ren shu-qin Yang Yu-meng Zhao Yong-jie Yuan Lu Zhang shu-min Han State Key Laboratory of Metastable Materials Science and Technology Yanshan University College of Environmental and Chemical Engineering Yanshan University

In this work,we synthesized LaFeO_3–xwt%Ni(x=0,5,10,15)composites via a solid-state reaction method by adding Ni to the reactants,La_2O_3 and Fe_2O_***-emission scanning electron microscopy(FE-SEM)and energy-dispersive X-ray spectroscopy(EDS)results revealed that Ni powders evenly dispersed among the LaFeO_3 particles and apparently reduced their aggregation,which imparted the composites with a loose ***,the Ni formed a conductive network,thus improving the conductivity of the *** maximum discharge capacity of the LaFeO_3 electrodes remarkably increased from 266.8 mAh·g^(–1)(x=0)to 339.7 mAh·g^(–1)(x=10).In particular,the high-rate dischargeability of the LaFeO_3–10wt%Ni electrode at a discharge current density of 1500 mA·g^(-1) reached 54.6%,which was approximately 1.5 times higher than that of the pure LaFeO_*** a Ni-modified loose structure not only increased the charge transfer rate on the surface of the LaFeO_3 particles but also enhanced the hydrogen diffusion rate in the bulk LaFeO_3.

关键词： LaFeO3 nickel modification electrochemical performances MH–Ni batteries

Treatment of simulated wastewater containing Reactive Red 195 by zero-valent iron/activated carbon combined with microwave discharge electrodeless lamp/sodium hypochlorite

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Journal of Environmental Sciences 2010年第4期22卷 512-518页

作者： Jie Fu zhen Xu Qing-Shan Li Song Chen shu-Qing An Qing-Fu Zeng Hai-liang Zhu State Key Laboratory of Pharmaceutical Biotechnology School of Life Sciences Nanjing University Nanjing 210093 China. Engineering Research Center for Clean Production of Textile Dyeing and Printing of Ministry of Education Wuhan University of Scienee & Engineering Wuhan 430073 China Pharmacy Department Shanghai Hospital of Skin Diseases and Sexually Transmitted Diseases Shanghai 200443 China

A comparative study of treatment of simulated wastewater containing Reactive Red 195 using zero-valent iron/activated carbon （ZVI/AC）, microwave discharge electrodeless lamp/sodium hypochlorite （MDEL/NaCIO） and the combination of ZVI/AC- MDEL/NaCIO was conducted. The preliminary results showed the two steps method of ZVI/AC-MDEL/NaCIO had much higher degradation efficiency than both single steps. The final color removal percentage was nearly up to 100% and the chemical oxygen demand reduction percentage was up to approximately 82%. The effects of operational parameters, including initial pH value of simulated wastewater, ZVI/AC ratio and particle size of ZVI were also investigated. In addition, from the discussion of synergistic effect between ZVI/AC and MEDL/NaCIO, we found that in the ZVI/AC-MEDL/NaCIO process, ZVI/AC could break the azo bond firstly and then MEDLfNaCIO degraded the aromatic amine products effectively. Reversing the order would reduce the degradation efficiency.

关键词： activated carbon microwave discharge electrodeless lamp Reactive Red 195 sodium hypochlorite zero-valent iron.

Existence and Dynamics of Bounded Traveling Wave Solutions to Getmanou Equation

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Communications in Theoretical Physics 2018年第12期69卷 672-676页

作者： zhen-shu Wen School of Mathematical Sciences Huaqiao University

In this paper, we study the existence and dynamics of bounded traveling wave solutions to Getmanou equations by using the qualitative theory of differential equations and the bifurcation method of dynamical systems. We show that the corresponding traveling wave system is a singular planar dynamical system with two singular straight lines, and obtain the bifurcations of phase portraits of the system under different parameters conditions. Through phase portraits, we show the existence and dynamics of several types of bounded traveling wave solutions including solitary wave solutions, periodic wave solutions, compactons, kink-like and antikink-like wave solutions. Moreover, the expressions of solitary wave solutions are given. Additionally, we confirm abundant dynamical behaviors of the traveling wave s olutions to the equation, which are summarized as follows: i) We confirm that two types of orbits give rise to solitary wave solutions, that is, the homoclinic orbit passing the singular point, and the composed homoclinic orbit which is comprised of two heteroclinic orbits and tangent to the singular line at the singular point of associated system. ii) We confirm that two types of orbits correspond to periodic wave solutions, that is, the periodic orbit surrounding a center,and the homoclinic orbit of associated system, which is tangent to the singular line at the singular point of associated system.

关键词： getmanou equation bounded traveling wave solutions existence bifurcations dynamics

Three antibacterial naphthoquinone analogues from cultured mycobiont of lichen Astrothelium sp

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Chinese Chemical Letters 2010年第7期21卷 842-845页

作者： Li Yan Sun zhen liang Liu Tao Zhang shu Bin Niu Zun Tian Zhao College of Pharmacology Taishan Medical UniversityTaian 271016China College of Life Sciences Shandong Normal UniversityJinan 250014China College of Chemistry and Chemical Engineering Taishan Medical UniversityTaian 271016China Key Lab of Systematic Mycology & Lichenology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China

A new naphthoquinone compound named 7-hydroxyl-8-methoxyltrypethelone 3 together with two known compounds trypethelone 1 and trypethelone methyl ether 2 was isolated from cultured mycobiont of Astrothelium *** structures were elucidated by 1D and 2D NMR spectroscopic analysis as well as comparison with those reported in *** 1 displayed significant antibacterial activity against Bacillus subtilis（ATCC 6633）,and showed modest antibacterial activity against Staphylococcus aureus col（MRSA）（CGMCC 1.2465）,while compounds 2 and 3 showed modest antibacterial activity against Enterococcus faecalis 850E（CGMCC 1.2135） and *** col（MRSA）（CGMCC 1.2465）.

关键词： Astrothelium sp. Lichen Mycobiont 7-Hydroxyl-8-methoxyltrypethelone

Effects of Twin-Dislocation and Twin-Twin Interactions on the Strain Hardening Behavior of TWIP Steels

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Journal of Iron and Steel Research International 2010年第12期17卷 70-74页

作者： WANG shu-han LIU zhen-yu WANG Guo-dong LIU Jun-liang liang Gao-fei LI Qiu-lin Graduate School at Shenzhen Tsinghua University Shenzhen 518055 Guangdong China The Key Laboratory of Rolling Technology and Automation Northeastern University Shenyang 110004 Liaoning China The Research and Development Institute Baosteel Co Ltd Shanghai 201900 China

Tensile tests of Fe-30Mn-5Si-2Al steel were carried out for different strains of 0.05, 0.14, 0.26, and up to the strain-to-failure in order to observe the evolution of microstructure during deformation and investigating the strain hardening behavior. Three-stage strain hardening behavior was observed in this steel during tensile test. In stage I , planar dislocation structure was observed by TEM and regarded as main deformation mechanism, and low strain hardening rate exponent was exhibited. Primary deformation twinning occurred in stage II , and the strain hardening rate exponent increased due to the blockage of dislocations＇ motion by twin boundaries. In stage III , the strain hardening rate exponent had increased to a value higher than 0.5. The obstacle effect of twin boundaries and twin-twin interact＇ion had been observed by TEM, and the interactions between primary and secondary twins were found to cause the additional hardening in addition to the obstacle effect on dislocations＇ motion, which led to the twinning induced plasticity effect in the later stage of deformation.

关键词： TWIP steel strain hardening twin dislocation