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Evaluating heavy metal contamination of riverine sediment cores in different land-use areas

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Frontiers of Environmental Science & Engineering 2020年第6期14卷 147-157页

作者： Wenzhong Tang liu sun Limin Shu Chuang Wang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Anthropogenic activities are regarded as the main sources of heavy metal pollution,yet few studies have investigated the effects of land-use setting on heavy metal accumulation in riverine *** on both total contents and geochemical fractions,heavy metal pollution,risk and toxicity were determined in riverine sediment cores from different land-use areas(mountain area-MA,farm area-FA,city area-CA,and industrial area-LA)of the Yang River Basin in North *** results showed that FA had higher contents of riverine sedimentary Cu;CA had higher contents of Cd;*** higher contents of both Cd and *** riverine sediments from FA and IA were contaminated with the investigated metals,although these concentrations were evaluated to have low potential ecological risk and no toxicity to benthic ***,a high proportion of Cd in the B1 fraction of riverine sediments in IA indicating high risk should receive more *** B1 fraction largely determined the contamination,risk and toxicity levels associated with heavy metals in the riverine sediments of the Yang River Basin.

关键词： Heavy metals Riverine sediments Pollution Land-use

Steel-Making and Continuous/Ingot Casting Scheduling of Mixed Charging Plan Based on Batch Splitting Policy

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Journal of Iron and Steel Research International 2012年第4期19卷 17-21页

作者： liu Wei sun Liang-liang State Key Laboratory of Synthetical Automation for Process Industries Northeastern UniversityShenyang 110004 Liaoning China

For steel-making and continuous/ingot casting are the key processes of modern iron and steel enterprises, this paper proposes a batch splitting schedule policy to solve continuous and ingot casting schedule of mixed whole/ half charging plan for steel making. First establish the model of continuous and ingot casting schedule of mixed whole/half charging plan according to the complex constraints. Then solve this model by heuristic algorithm. Finally use actual data to prove the proposed algorithmrs validity and analyze the application result in steel plant.

关键词： continuous/ingot casiing whole/half charging batch splitting policy scheduling

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Research progress in the effects of terahertz waves on biomacromolecules

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Military Medical Research 2022年第1期9卷 63-70页

作者： liu sun Li Zhao Rui-Yun Peng Beijing Institute of Radiation Medicine Haidian District27 Taiping RoadBeijing 100850China

With the rapid development of terahertz technologies,basic research and applications of terahertz waves in biomedicine have attracted increasing *** rotation and vibrational energy levels of biomacromolecules fall in the energy range of terahertz waves;thus,terahertz waves might interact with ***,terahertz waves have been widely applied to explore features of the terahertz spectrum of ***,the effects of terahertz waves on biomacromolecules are largely *** some progress has been reported,there are still numerous technical barriers to clarifying the relation between terahertz waves and biomacromolecules and to realizing the accurate regulation of biological macromolecules by terahertz ***,further investigations should be conducted in the *** this paper,we reviewed terahertz waves and their biomedical research advantages,applications of terahertz waves on biomacromolecules and the effects of terahertz waves on *** findings will provide novel ideas and methods for the research and application of terahertz waves in the biomedical field.

关键词： Terahertz waves Biomacromolecules Effect Review

STATE-FEEDBACK ADAPTIVE STABILIZING CONTROL DESIGN FOR A CLASS OF HIGH-ORDER NONLINEAR SYSTEMS WITH UNKNOWN CONTROL COEFFICIENTS

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Journal of Systems Science & Complexity 2007年第3期20卷 350-361页

作者： Zongyao sun Yungang liu School of Control Science and Engineering Shandong University Jinan 250061 China.

In this paper, a new approach is successfully addressed to design the state-feedback adaptive stabilizing control law for a class of high-order nonlinear systems in triangular form and with unknown and nonidentical control coefficients, whose stabilizing control has been investigated recently under the knowledge that the lower bounds of the control coefficients are exactly known. In the present paper, without any knowledge of the lower bounds of the control coefficients, based on the adaptive technique and appropriately choosing design parameters, we give the recursive design procedure of the stabilizing control law by utilizing the approach of adding a power integrator together with tuning functions. The state-feedback adaptive control law designed not only preserves the equilibrium at the origin, but also guarantees the global asymptotic stability of the closed-loop states and the uniform boundedness of all the other closed-loop signals.

关键词： Adaptive stabilizing control adding a power integrator high-order nonlinear systems,state-feedback unknown control coefficients.

Solution-based Chemical Strategies to Purposely Control the Microstructure of Functional Materials

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Journal of Materials Science & Technology 2008年第4期24卷 641-648页

作者： Fei liu Congting sun Chenglin YAN Dongfeng XUE State Key Laboratory of Fine Chemicals Department of Materials Science and Chemical Engineering School of Chemical Engineering Dalian University of Technology Dalian 116012 China

Micro/nanostructured crystals with controlled architectures are desirable for many applications in optics, electronics, biology, medicine, and energy conversions. Low-temperature, aqueous chemical routes have been widely investigated for the synthesis of particles, and arrays of oriented nanorods and nanotubes. In this paper, based on the ideal crystal shapes predicted by the chemical bonding theory, we have developed some potential chemical strategies to tune the microstructure of functional materials, ZnS and Nb205 nanotube arrays, MgO wiskers and nestlike spheres, and cubic phase Cu2O microcrystals were synthesized here to elucidate these strategies. We describe their controlled crystallization processes and illustrate the detailed key factors controlling their growth by examining various reaction parameters. Current results demonstrate that our designed chemical strategies for tuning microstructure of functional materials are applicable to several technologically important materials, and therefore may be used as a versatile and effective route to the controllable synthesis of other inorganic functional materials.

关键词： Functional materials Chemical strategy Chemical bonding theory Microstructure

Surface Roughness Effects on Vortex Torque of Air Supported Gyroscope

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Chinese Journal of Aeronautics 2011年第1期24卷 90-95页

作者： LIANG Yingchun liu Jingshi sun Yazhou LU Lihua School of Mechatronics Engineering Harbin Institute of Technology Harbin 150001 China

In order to improve the drift precision of air supported gyroscope, effects of surface roughness magnitude and direction on vortex torque of air supported gyroscope are studied. Based on Christensen’s rough surface stochastic model and consistency transformation method, Reynolds equation of air supported gyroscope containing surface roughness information is established. Also effects of mathematical models of main machining errors on vortex torque are established. By using finite element method, the Reynolds equation is solved numerically and the vortex torque in the presence of machining errors and surface roughness is calculated. The results show that surface roughness of slit has a significant effect on vortex torque. Transverse surface roughness makes vortex torque greater, while longitudinal surface roughness makes vortex torque smaller. The maximal difference approaches 11.4% during the range analyzed in this article. However surface roughness of journal influences vortex torque insignificantly. The research is of great significance for designing and manufacturing air supported gyroscope and predicting its performance.

关键词： air supported gyroscope surface roughness Christensen’s stochastic model consistency transformation vortex torque

Role of Tip60 tumor suppressor in DNA repair pathway

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Chinese Science Bulletin 2011年第12期56卷 1212-1215页

作者： liu ZhiJian sun YingLi Beijing Institute of Genomics Chinese Academy of Sciences Beijing 100029 China

To prevent the damage caused by DNA strand breaks, eukaryotic cells have evolved a series of highly conserved DNA repair mechanisms. The ubiquitously expressed acetyltransferase, Tip60, plays a central role in ATM (ataxia-telangiectasia mutated) activation which is involved in DNA repair. Recent work uncovered a new mechanism of ATM activation mediated by Tip60 and demonstrated that histone methylation, specifically, trimethylation of histone H3, is a key factor in the process. Here, we review the current understanding of how Tip60 is activated and how it activates ATM in response to DNA damage.

关键词： DNA修复抑癌作用组蛋白H3 DNA链断裂毛细血管扩张修复机制 DNA损伤 ATM

Denitrification characteristics of a marine origin psychrophilic aerobic denitrifying bacterium

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Journal of Environmental Sciences 2011年第11期23卷 1888-1893页

作者： Haiyan Zheng Ying liu Guangdong sun Xiyan Gao Qingling Zhang Zhipei liu State Key Laboratory of Microbial Resources Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China.

A psychrophilic aerobic denitrifying bacterium,strain S1-1,was isolated from a biological aerated filter conducted for treatment of recirculating water in a marine aquaculture *** S1-1 was preliminarily identified as Psychrobacter *** on the analysis of its 16S rRNA gene sequence,which showed 100% sequence similarity to that of Psychrobacter *** S1-1 grew well either in high nitrate or high nitrite conditions with a removal of 100% nitrate or 63.50% nitrite,and the total nitrogen removal rates could reach to 46.48% and 31.89%,*** results indicated that nitrate was mainly reduced in its logarithmic growth phase with a very low leve1 accumulation of nitrite,suggesting that the aerobic denitrification process of strain S1-1 occurred mainly in this *** GC-MS results showed that N 2 O was formed as the major intermediate during the aerobic denitrifying process of strain ***,factors affecting the growth of strain S1-1 and its aerobic denitrifying ability were also *** showed that the optimum aerobic denitrification conditions for strain S1-1 were sodium succinate as carbon source,C/N ratio15,salinity 10 g/L NaCl,incubation temperature 20°C and initial pH 6.5.

关键词： nitrogen removal aerobic denitrification marine environment low temperature Psychrobacter sp.S1-1

A Semiparametric Additive Rates Model for Clustered Recurrent Event Data

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Acta Mathematicae Applicatae Sinica 2013年第1期29卷 55-62页

作者： Sui He Fen Wang liu-quan sun School of Mathematics and Statistics Central China Normal University Institute of Applied Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences

Recurrent event data often arises in biomedical studies, and individuals within a cluster might not be independent. We propose a semiparametric additive rates model for clustered recurrent event data, wherein the covariates are assumed to add to the unspecified baseline rate. For the inference on the model parameters, estimating equation approaches are developed, and both large and finite sample properties of the proposed estimators are established.

关键词： additive rates clustered failure time data estimating equation marginal model recurrentevents