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FRACTIONAL INTEGRALS OF PERIODIC FUNCTIONS OF SEVERAL VARIABLES

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Analysis in Theory and Applications 1993年第1期9卷 82-96页

作者： wang shiming Mathematics Section Dept.of Basic Courses Zhejiang Institute of Technology Hangzhou 310014 P.R.China

In this paper it has been systematically studied the imbedding properties o f fractional integral operators of periodic functions of several variables,and isomorphic properties of fractional intregral operators in the spaces of Lipschitz continuous functions. It has also been proved that the space of fractional integration,the space of Lipschitz continuous functions and the Sobolev space are identical in L^*** obtainedhere are not true for fractional integrals(or Riesz potentials)in R^n.

关键词： Th FRACTIONAL INTEGRALS OF PERIODIC FUNCTIONS OF SEVERAL VARIABLES

Assessment on contaminations in sediments of an intake and the inflow canals in Taihu Lake, China

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Frontiers of Environmental Science & Engineering 2015年第4期9卷 665-674页

作者： Xiaolong wang shiming DING Qi ZHANG Weiping HU State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Linmology Chinese Academy of Sciences Nanjing 210008 China

As the second largest freshwater lake in China, Taihu Lake provides water supply to approximately 32 million inhabitants around the lake. However, dramatically increased pollution has threatened the safety of drinking water supply in recent years. In the present study, we investigated the contaminations of nutrients and heavy metals in the sediments of an intake and inflow canals in Gonghu Bay, Taihu Lake. Moreover, we also examined the impact of human activities on spatial distribution char- acteristics of contaminations. Our results showed that the intake presented relatively lower concentrations of phos- phorus and nitrogen compared with inflow canals. However, the concentrations of Cr, Ni, Cu, Zn and Pb in the sediments of the intake exceeded the lowest effect level （LEL） values, indicating a potential risk to drinking water resource. In addition, the concentrations of Ni in the sediments of Tianji Canal and Jinshu Canal exceeded the severe effect level （SEL） value. More importantly, the concentrations of Cu in the sediments of Tianji Canal exceeded three times of the SEL value. Multivariate statistical analysis confirmed that the domestic sewage primarily contributed to the nutrient accumulation, and the leakage of electronic trash dominated the enrichment of metals in the sediments. Taken together, more effort should be made to ensure the security of water resources in Taihu Lake, especially for the treatment of domestic sewage and industrial wastewater.

关键词： drinking water resource nutrients heavy metals sediments Taihu Lake

Selective adsorption of silver ions from aqueous solution using polystyrene-supported trimercaptotriazine resin

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Journal of Environmental Sciences 2012年第12期24卷 2166-2172页

作者： shiming wang Hongling Li Xiaoya Chen Min Yang Yanxing Qi National Engineering Research Center for Fine Petrochemical Intermediates Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Graduate-University of Chinese Academy of Sciences Beijing 1001949China

Tdmercaptotriazine-functionalized polystyrene chelating resin was prepared and employed for the adsorption of Ag（I） from aqueous solution. The adsorbent was characterized according to the following techniques： Fourier transform infrared spectroscopy, elemental analysis, scanning electron microscopy and the Brunauer-Emmet-Teller method. The effects of initial Ag（I） concentration, contact time, solution pH and coexisting ions on the adsorption capacity of Ag（I） were systematically investigated. The maximum adsorption capacity of AgO） was up to 187.1 mg/g resin at pH 0.0 and room temperature. The kinetic experiments indicated that the adsorption rate of Ag（I） onto the chelating resin was quite fast in the first 60 rain and reached adsorption equilibrium after 360 min. The adsorption process can be well described by the pseudo second-order kinetic model and the equilibrium adsorption isotherm was closely fitted by the Langmuir model. Moreover, the chelating resin could selectively adsorb more Ag（I） ions than other heavy metal ions including： Cu（Ⅱ）, Zn（Ⅱ）, Ni（Ⅱ）, Pb（Ⅱ） and Cr（Ⅲ） during competitive adsorption in the binary metal species systems, which indicated that it was a highly selective adsorbent of Ag（I） from aqueous solution.

关键词： trimercaptotriazine macroporous chloromethyl resin functionalized adsorption silver ions

Microstructure and mechanical properties of Mg-Nd-Zn-Zr billet prepared by direct chill casting

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Journal of Magnesium and Alloys 2018年第1期6卷 95-99页

作者： Xingwei Zheng Jie Dong shiming wang College of Engineering Science and Technology Shanghai Ocean University201306 ShanghaiPR China National Engineering Research Center of Light Alloy Net Forming Shanghai Jiao Tong University200240 ShanghaiPR China

High-quality Mg-Nd-Zn-Zr magnesium alloy billets with diameter of 200 mm were successfully prepared by direct chill(DC)*** results show that microstructures of the as-cast billet prepared by DC casting are mainly composed of equiaxed a-Mg and Mg 12 Nd eutectic compound distributing along the grain *** average grain size decreases along the radius of the *** the alloying elements of Nd and Zn distribute homogeneously across the large *** optimum process parameters for DC casting of the Mg-Nd-Zn-Zr magnesium alloy billet with diameter of 200 mm have been experimentally determined as follows:casting temperature 710℃ and casting speed 80 mm/min.

关键词： Magnesium alloy Direct chill casting Microstructure Mechanical properties

Discovery of Paleoproterozoic rapakivi granite on the northern margin of the Yangtze block and its geological significance

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Chinese Science Bulletin 2011年第3期56卷 306-318页

作者： ZHANG LiJuan MA ChangQian wang LianXun SHE ZhenBing wang shiming Faculty of Earth Sciences China University ofGeosciences Wuhan 430074 China State Key Laboratory of Geological Processes and Mineral Resources CUG Wuhan 430074 China

The Huashanguan rapakivi pluton in Zhongxiang,Hubei Province,China,is the first discovered Proterozoic rapakivi pluton in the Yangtze *** on field and petrographical observations,a typical rapakivi texture was found in the northern portion of the Huashanguan granitic *** all the K-feldspar phenocrysts were round to oval in shape and most had plagioclase coatings known as rapakivi *** feldspars and quartz had two or more ***,the Huashanguan rapakivi granites were characterized as having high values of Si,K,Fe,Th,U,La,Ga,Ce,Sm and LREE,low values of Ca,Mg,Sr,Nb,Y and HREE,and a negative Eu *** geochemical characteristics of the Huashanguan granites were concordant with typical rapakivi granites,and had an affinity to A-type ***-ICP-MS U-Pb zircon dating also was *** dating yielded a 207Pb/206Pb weighted mean age of 1851±18 Ma (MSWD =1.2),which represents the age of the pluton *** age of 803±170 Ma at the lower intercept in the concordia diagram corresponds to the age of a later deformation event which affected the pluton,and suggests that the Huashanguan pluton was influenced by Neoproterozoic thermo-tectonic events after its *** discovery of Paleoproterozoic Huashanguan rapakivi granites indicates continental rifting or a post-orogenic extensional event that took place in the Paleoproterozoic in the Yangtze *** events may be related to the breakup of the Paleoproterozoic Columbia supercontinent.

关键词：环斑花岗岩古元古代扬子陆块地质意义花岗岩体构造事件北缘地球化学特征

DETECTION OF LONGITUDINAL DEFECT IN PIPES USING TORSIONAL MODES

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Chinese Journal of Mechanical Engineering 2006年第1期19卷 146-150页

作者： LIU Zenghua WU Bin HE Cunfu YANG shiming wang Xiuyan College of Mechanical Engineering and Applied Electronics Technology Beijing University of Technology Beijing 100022 China

The multi-modes and disperse characteristics of torsional modes in pipes are investigated theoretically and experimentally. At all frequencies, both phase velocity and group velocity of the lowest torsional mode T（0,1） are constant and equal to shear wave velocity. T（0,1） mode at all frequencies is the fastest torsional mode. In the experiments, T（0,1） mode is excited and received in pipes using 9 thickness shear vibration mode piezoelectric ceramic elements. Furthermore, an artificial longitudinal defect of a 4 m long pipe is detected using T（0,1） mode at 50 kHz. Experimental results show that it is feasible for longitudinal defect detection in pipes using T（0,1） mode of ultrasonic guided waves.

关键词： Torsional mode Pipe Longitudinal defect Detection Ultrasonic guided waves

Visible-light photocatalytic H_2 evolution over a series of transition metal substituted Keggin-structure heteropoly blues

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Chinese Science Bulletin 2012年第18期57卷 2265-2268页

作者： ZhenLi wang Ying Lu YangGuang Li shiming wang EnBo wang NE Normal Univ Dept Chem Minist Educ Key Lab Polyoxometalate Sci Changchun 130024 Peoples R China

The visible light photocatalytic H 2 evolution activities of a series of transition-metal substituted Keggin-structure heteropoly blues K 6 SiW 11 O 39 M(H 2 O)·nH 2 O (M=Co,Ni,Cu and Zn) were systematically studied with Pt nanoparticles as *** H 2 evolution rates were 150,98,65 and 48 mol h-1g-1 for SiW 11 Cu,SiW 11 Ni,SiW 11 Co and SiW 11 Zn,respectively,meaning that the order of photocatalytic activity of these heteropoly blues from transition-metal substituted polyoxometalates was:SiW 11 Cu > SiW 11 Ni > SiW 11 Co > SiW 11 *** catalysts could be efficiently reused for at least 5 cycles.

关键词： Keggin结构光催化活性过渡金属进化速率杂多蓝可见光氢气多金属氧酸盐

Identifcation of large-scale goaf instability in underground mine using particle swarm optimization and support vector machine

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International Journal of Mining Science and Technology 2013年第5期23卷 701-707页

作者： Zhou Jian Li Xibing Hani S.Mitri wang shiming Wei Wei School of Resources and Safety Engineering Central South University Hunan Key Lab of Resources Exploitation and Hazard Control for Deep Metal Mines Department of Mining and Materials Engineering McGill University

An approach which combines particle swarm optimization and support vector machine(PSO–SVM)is proposed to forecast large-scale goaf instability(LSGI).Firstly,influencing factors of goaf safety are analyzed,and following parameters were selected as evaluation indexes in the LSGI:uniaxial compressive strength(UCS)of rock,elastic modulus(E)of rock,rock quality designation(RQD),area ration of pillar(Sp),the ratio of width to height of the pillar(w/h),depth of ore body(H),volume of goaf(V),dip of ore body(a)and area of goaf(Sg).Then LSGI forecasting model by PSO-SVM was established according to the influencing *** performance of hybrid model(PSO+SVM=PSO–SVM)has been compared with the grid search method of support vector machine(GSM–SVM)*** actual data of 40 goafs are applied to research the forecasting ability of the proposed method,and two cases of underground mine are also validated by the proposed *** results indicated that the heuristic algorithm of PSO can speed up the SVM parameter optimization search,and the predictive ability of the PSO–SVM model with the RBF kernel function is acceptable and robust,which might hold a high potential to become a useful tool in goaf risky prediction research.

关键词： Goaf Risk identifcation Underground mine Prediction Particle swarm optimization Support vector machine

Identification of QTL for kernel number-related traits in a rice chromosome segment substitution line and fine mapping of qSP1

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The Crop Journal 2019年第4期7卷 494-503页

作者： Fuying Ma Xiaoyan Zhu Hui wang shiming wang Guoqing Cui Ting Zhang Zhenglin Yang Guanghua He Yinghua Ling Nan wang Fangming Zhao Rice Research Institute Academy of Agricultural Sciences Southwest University

A chromosome segment substitution line (CSSL) is a powerful tool for combining quantitative trait locus (QTL) mapping with the pyramiding of desirable alleles. The rice CSSL Z1364 with increased kernel number was identified in a BC3F8 population derived from a cross of Nipponbare as the recipient with Xihui 18 as the donor parent. Z1364 carried three substitution segments distributed on chromosomes 1, 6, and 8. The mean substitution length was 1.19 Mb. Of 17 QTL identified on the substitution segments, qSP1 for spikelets per panicle, qSSD1 for seed-set density, and qNSB1 for number of secondary branches explained respectively 57.34%, 87.7%, and 49.44% of the corresponding phenotypic variance and were all linked to RM6777. Chi-square analysis showed that the increased kernel number in Z1364 was inherited recessively by a single gene. By fine mapping, qSP1 was delimited to a 50-kb region on the short arm of chromosome 1. Based on DNA sequence, a previously uncharacterized rice homolog of Arabidopsis thaliana AT4G32551 was identified as a candidate gene for qSP1 in which mutation increases the number of spikelets and kernels in Z1364. qSP1 was expressed in all tissues, but particularly in 1-cm panicles. The expression levels of OsMADS22, GN1A, and DST were upregulated and those of LAX2, GNP1, and GHD7 were downregulated in Nipponbare. These results provide a foundation for functional research on qSP1.

关键词： Rice Chromosome segment substitution line Increased number of kernels qSP1 QTL mapping for yield traits