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Water Science and Engineering 2017年第4期10卷 311-319页

作者： Hai-bo Yang En-chong Li Yong Zhao qiu-hua Liang School of Water Conservancy and Environmental Engineering Zhengzhou University State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research School of Civil Engineering and Geosciences Newcastle University

Implementation of the water-sediment regulation(WSR) scheme, mainly focused on solving the sedimentation problems of reservoirs and the lower reaches of the Yellow River, has inevitably influenced the sediment distribution and coastal morphology of the Yellow River *** coastline delineation and suspended sediment concentration(SSC) retrieval methods, this study investigated water and sediment changes,identified detailed inter-annual and intra-annual variations of the coastline and SSC in the normal period(NP: 1986-2001, before and after the flood season) and WSR period(WSRP: 2002-2013, before and after WSR). The results indicate that(1) the sedimentation in the low reaches of the Yellow River turned into erosion from 2002 onward;(2) the inter-annual coastline changes could be divided into an accretion stage(1986-1996), a slow erosion stage(1996-2002), and a slow accretion stage(2002-2013);(3) an intra-annual coastline extension occurred in the river mouth in most years of the WSRP; and(4) the mean intra-annual accretion area was 0.789 km^2 in the NP and 4.73 km2 in the WSRP,and the mean SSC increased from 238 mg/L to 293 mg/L in the NP and from 192 mg/L to 264 mg/L in the WSRP.

关键词： Coastline Suspended sediment concentration Water-sediment regulation Remote sensing Yellow River Estuary

Erythromycin Resistance of Streptococcus suis Isolates In Vivo

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Agricultural Sciences in China 2009年第4期8卷 502-507页

作者： JIANG Cheng-gang LI Yan-hua CAI Xue-hui qiu hua-ji TONG Heng-min LIU Di-qiu LEI Lian-cheng SUN Chang-jiang Division of Swine Infectious Diseases National Key Laboratory of Veterinary Biotechnology Harbin Veterinary Research Institute Chinese Academy of Agricultural Sciences Harbin 150001 P.R. China Northeast Agricultural University Harbin 150030 P.R.China Husbandry and Veterinary Institute of Jilin University Changchun 130062 P.R.China

In order to study erythromycin resistance of Streptococcus suis under high or low concentration of selective drug pressure, Streptococcus suis strain LN was isolated from a diseased pig in 2005 and showed to be susceptible to erythromycin as determined by disc diffusion and tube dilution tests. In this study, clean level rabbits were divided into three groups of six rabbits each, including a prevention dosage group, a treatment dosage group, and a control group. After injection with S. suis strain LN, erythromycin （20 μg mL^-1） was taken orally in the prevention dosage group, erythromycin （5 mg kg^-1） was injected intramuscularly in the treatment dosage group, and no treatment was given in the control group. S. suis with intermediate resistance to erythromycin was isolated on the 5th day after infection from the prevention dosage group （5th PDG） and on the 7th day after infection from the treatment dosage group （7th TDG）. Both isolates were determined to be the constitutive macrolide-lincosamide-streptogramin B （cMLSB） resistance phenotype. The resistance gene ermB was detected in all of the isolates. The results suggested that both the 5th PDG and 7th TDG isolates had a mutation （A2372T） in the 23S rRNA gene. In addition, the 5th PDG isolates had a mutation in ribosomal protein L4 （detected as G268A） and a mutation in ribosomal protein L22 （A345C）; and the 7th TDG isolates had a C insertion at site 564. Each of these mutations is considered as a possible mechanism of erythromycin resistance in S. suis strain LN. This study demonstrated that erythromycin resistance was readily induced in S. suis at a low erythromycin dose creating selective pressure in vivo. Resistance appeared to be mediated by ribosome methylation, encoded by the ermB gene.

关键词： Streptococcus suis erythromycin in vivo resistance

Preconcentration of chlorophenols in water samples using threedimensional graphene-based magnetic nanocomposite as absorbent

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Chinese Chemical Letters 2014年第8期25卷 1185-1189页

作者： Xing-Li Liu Chun Wang qiu-hua Wu Zhi Wang College of Science Agricultural University of Hebei

In this paper, a novel magnetic solid-phase extraction method using three-dimensional graphene-based magnetic nanocomposite as adsorbent for the preconcentration of several chlorophenols from water samples prior to high-performance liquid chromatography analysis was developed. Various experimental parameters were investigated. Under the optimum conditions, the enrichment factors of the method were in the range of 186–312, and the limit of detection（S/N = 3） was 0.10 ng/mL. The recoveries of the method were in the range between 85.1% and 101.2%. The developed method has been successfully applied to the determination of chlorophenols in environmental water samples.

关键词： Three-dimensional graphene Magnetic adsorbent High performance liquid chromatography Chlorophenols Water samples

Preface for special section on flood modeling and resilience

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Water Science and Engineering 2017年第4期10卷 265-266页

作者： Jing-ming Hou qiu-hua Liang Gang Wang Reinhard Hinkelmann Institute of Water Resources and Hydro-Electric Engineering Xi'an University of Technology State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University School of Engineering Newcastle UniversityNewcastle upon TyneNEI 7RUUK Chair of Water Resources Management and Modeling of Hydrosystems Technische Universitt Berlin

Climate change has led to increased frequency, intensity,and duration of extreme weather events, e.g., intense rainfall,heat waves, droughts, and storm surges, worsened byrapid population growth and urbanization at the global *** can be found in the exceptional number of unprecedentedweather extremes and the resulting naturalhazards, especially flooding, as seen in the last few *** example, the UK has experienced numerous storms andsevere floods in the last decade, particularly in 2007, 2012,and 2015, with 2012 being recorded as the second wettest year in the UK and the wettest ever in England. These events have resulted in lives lost and tremendous economic damage. The UK is not alone. Similarly unusual weather events have been reported across the globe. In China,different types of flooding threaten 1/10 of the country's total area, millions of hectares of farmland, and over 100 large cities, making it one of the most vulnerable countries to flooding.

关键词： Climate change has led to increased frequency

A Class of Parameter-free Filled Functions for Box-constrained System of Nonlinear Equations

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Acta Mathematicae Applicatae Sinica 2016年第2期32卷 355-364页

作者： Liu-yang YUAN Zhong-ping WAN qiu-hua TANG Yue ZHENG Hubei Province Key Laboratory of Systems Science in Metallurgical Process Wuhan University of Science and Technology School of Mathematics and Statistics Wuhan University Industrial Engineering Department Wuhan University of Science and Technology School of Management Huaibei Normal University

In this paper, a class of parameter-free filled functions is proposed for solving box-constrained system of nonlinear equations. Firstly, the original problem is converted into an equivalent global optimization problem. Subsequently, a class of parameter-free filled functions is proposed for solving the problem. Some properties of the new class of filled functions are studied and discussed. Finally, an algorithm which neither computes nor explicitly approximates gradients during minimizing the filled functions is presented. The global convergence of the algorithm is also established. The implementation of the algorithm on several test problems is reported with satisfactory numerical results.

关键词： system of nonlinear equations global optimization filled function method local minimizer globalminimizer

Measures and dimensions of fractal sets in local fields

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Progress in Natural Science:Materials International 2006年第12期16卷 1260-1268页

作者： qiu hua** and SU Weiyi(Department of Mathematics, Nanjing University, Nanjing 210093, China) Department of Mathematics Nanjing University Nanjing 210093 China

The study of fractal analysis over the local fields as underline spaces is very important since it can motivate new approaches and new ideas, and discover new techniques in the study of fractals. To study fractal sets in a local field K, in this paper, we define several kinds of fractal measures and dimensions of subsets in K. Some typical fractal sets in K are constructed. We also give out the Hausdorff dimensions and measures, Box-counting dimensions and Packing dimensions, and stress that there exist differences between fractal analysis on local fields and Euclidean spaces. Consequently, the theoretical foundation of fractal analysis on local fields is established.

关键词： local field p-series field Hausdorff measure and dimension Boxcounting dimension Packing measure and dimension Cantor type set.

A novel method for the determination of trace copper in cereals by dispersive liquid-liquid microextraction based on solidification of floating organic drop coupled with flame atomic absorption spectrometry

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Chinese Chemical Letters 2011年第4期22卷 473-476页

作者： Chun Xia Wu qiu hua Wu Chun Wang Zhi Wang Key Laboratory of Bioinorganic Chemistry College of SciencesAgricultural University of HebeiBaoding 071001China

A novel,simple,rapid,efficient and environment-friendly method for the determination of trace copper in cereal samples was developed by using dispersive liquid-liquid microextraction based on solidification of floating organic drop（DLLME-SFO） followed by flame atomic absorption *** the DLLME-SFO,copper was complexed with 8-hydroxy quinoline and extracted into a small volume of 1-dodecanol,which is of low density,low toxicity and proper melting point near room temperature. The experimental parameters affecting the extraction efficiency were investigated and *** the optimum conditions, the calibration graph exhibited linearity over the range of 0.5—500 ng/mL with the correlation coefficient（r） of *** enrichment factor was 122 and the limit of detection was 0.1 ng/*** method was applied to the determination of copper in the complex matrix samples such as rice and millet with the recoveries for the spiked samples at 5.0 and 10.0 u,g/g falling in the range of 92.0-98.0%and the relative standard deviation of 3.9-5.7%.

关键词： Dispersive liquid-liquid microextraction based on solidification of floating organic droplet Flame atomic absorption spectrometry Copper Cereal samples

Forecasting conductivities of LiBOB-EC/DEC electrolytes by the mass triangle model

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International Journal of Minerals,Metallurgy and Materials 2009年第4期16卷 463-467页

作者： Jia-yuan huang Bi-tao Yu Fu-shen Li Wei-hua qiu School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Conductivities of lithium bis（oxalato）borate （LiBOB）-ethyl carbonate （EC）/diethyl carbonaten （DEC） electrolytes at 25℃ and 50℃ were studied. The electrolyte component with the highest conductivity at each temperature was obtained through changing the concentration of LiBOB and the ratio of EC/DEC. The mass triangle model was applied to calculate the conductivity of Li- BOB-EC/DEC ternary system at 25℃ and 50℃. The results show that the calculated and experimental results have reached a good agreement. Therefore, it is expected that the experimental work can be vastly reduced by introducing the mass triangle model.

关键词： lithium bis(oxalato)borate (LiBOB) electrolyte conductivity mass triangle model

Modeling of friction stir welding process for tools design

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Frontiers of Materials Science 2011年第2期5卷 236-245页

作者： San-Bao LIN Yan-hua ZHAO Zi-qiu HE Lin WU State Key Lab of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China

A three-dimensional friction stir welding （FSW） process model has been developed based on fluid mechanics. The material transport in the welding process has been regarded as a laminar, viscous, and non-Newtonian liquid that flows past a rotating pin. A criterion to divide the weld zone has been given on the basis of cooperation of velocity field and viscosity field. That is, the η0-easy-flow zone that existed near the tool pin corresponded to the weld nugget zone; the area between the η0-easy-flow zone and η1-viscosity band is corresponded to the thermal-mechanical affected zone （TMAZ）. The model gives some useful information to improve the understanding of material flow in FSW through the simulation result of velocity distribution. In order to appraise the friction stir pin design, three kinds of pin geometry, one is column pin, the second is taper pin, and the last one is screw threaded taper pin, were used in the model. The pin geometry seriously affected the simulation result of velocity distribution in the η0-easy-flow zone. The velocity distribution in the η0-easy-flow zone can be considered as the criterion of optimizing friction stir tool design. This study will benefit to direct the friction stir tool design.

关键词： friction stir welding (FSM) 2014Al alloy, model, flow, fdction stir pin

Cesium hydroxide-catalyzed hydrothiolation of alkynyl selenides to highly stereo- and regioselectively synthesize(Z)-1-organoseleno-2-arylthio-1-alkenes

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Chinese Chemical Letters 2011年第6期22卷 687-690页

作者： Ai He Yu Ren hua qiu Nian Yuan Tan Li Feng Peng Xin hua Xu Department of Biological and Chemical Engineering Hunan Mechanical and Electrical Polytechnic Changsha 410151 China College of Chemistry and Chemical Engineering Hunan University Changsha 410082 China

In the presence of catalytic amount of cesium hydroxide the hydrothiolation of alkynyl selenides occurred at room temperature in DMF under nitrogen atmosphere to give exclusive（Z）-1-organoseleno-2-arylthio-1-alkene in excellent *** could provide a new and expedient way for the preparation of（Z）-1-arylseleno-2-arylthio-1-alkene.

关键词： Hydrothiolation Cesium hydroxide Alkynyl selenides (Z)-1-Organoseleno-2-arylthio-1-alkene