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Acta Oceanologica Sinica 2015年第5期34卷 22-28页

作者： ZHENG Fei WANG hui WAN Liying International Center for Climate and Environment Science (ICCES) Institute of Atmospheric PhysicsChinese Academy of Sciences National Meteorological Center Key Laboratory of Research on Marine Hazards Forecasting National Marine Environmental Forecasting Center

In this paper, interannual variations of the ocean dynamic height over the tropical Pacific are diagnosed using three-dimensional temperature and salinity fields from Argo profiles, with a focus on the effects of interannually varying salinity on the El Nino-Southern Oscillation （ENSO） evolutions. The diagnostic analyses clearly demonstrate a significant and large role that the salinity field plays in modulating the sea surface dynamic height （SSDH） in the western tropical Pacific. In particular, the contribution of the interannually varying salinity to the interannual variations in SSDH approximately equals to that of the interannually varying temperature. Over the western equatorial Pacific, the salinity variability was responsible for a 30% to 40% reduction in SSDH anomaly in opposition to the thermal build up in SSDH anomaly, providing an important contribution to modulating the seasonal-to-interannual evolution of the tropical Pacific Ocean and affecting the developing of ENSO events.

关键词： salinity effect SSDH ENSO Argo western tropical Pacific

Studies on vibration characteristics of a pear using finite element method

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第6期7卷 491-496页

作者： SONG hui-zhi WANG Jun LI Yong-hui Department of Biosystems Engineering Zhejiang University Hangzhou 310029 China

The variation of the vibration characteristics of a Huanghua pear was investigated using finite element simulations. A new image processing technique was used to obtain the unsymmetrical and un-spherical geometrical model of a pear. The vibra-tion characteristics of this type of pear with the correlation of its behavior with geometrical configurations and material charac-teristics were investigated using numerical modal analysis. The results showed that the eigenfrequency increased with the in-creasing pear young’s modulus, while decreased with increasing pear density, and decreased with increasing pear volume. The results of this study provided foundation for further investigations of the physical characteristics of fruits and vegetables by using finite element simulations.

关键词： Pear Vibration characteristics Unsymmetrical and un-spherical model Finite element analysis

Roles of initial ocean states on predicting the 2002/03 central Pacific El Nino

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Acta Oceanologica Sinica 2015年第12期34卷 72-79页

作者： ZHENG Fei WANG hui WAN Liying International Center for Climate and Environment Science (ICCES) Institute of Atmospheric Physics Chinese Academy of Sciences National Meteorological Center Key Laboratory of Research on Marine Hazards Forecasting National Marine Environmental Forecasting Center

The 2002/03 El Ni？o event, a new type of El Ni？o with maximum warm anomaly occurring in the central equatorial Pacific, is known as central-Pacific（CP） El Ni？o. In this study, on the basis of an El Ni？o prediction system, roles of the initial ocean surface and subsurface states on predicting the 2002/03 CP El Ni？o event are investigated to determine conditions favorable for predicting El Ni？o growth and are isolated in three sets of hindcast experiments. The hindcast is initialized through assimilation of only the sea surface temperature（SST）observations to optimize the initial surface condition（Assim_SST）, only the sea level（SL） data to update the initial subsurface state（Assim_SL）, or both the SST and SL data（Assim_SST＋SL）. Results highlight that the hindcasts with three different initial states all can successfully predict the 2002/03 El Ni？o event one year in advance and that the Assim_SST＋SL hindcast performs best. A comparison between the various sets of hindcast results further demonstrates that successful prediction is significantly affected by both of the initial surface and subsurface conditions, but in different developing phases of the 2002/03 El Ni？o event. The accurate initial surface state can easier trigger the prediction of the 2002/03 El Ni？o, whereas a more reasonable initial subsurface state can contribute to improving the prediction in the growth of the warm event.

关键词： Initial oceanic states CP El Ni?o Seasonal prediction data assimilation

Arithmetic Expression Evaluations with Membranes

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Chinese Journal of Electronics 2014年第1期23卷 55-60页

作者： GUO Ping CHEN Haizhu ZHENG hui College of Computer Science Chongqing University Chongqing Key Laboratory of Software Theory and Technology Department of Software Engineering Chongqing College of Electronic Engineering

Arithmetic operations and expression evaluations are fundamental in computing models. This paper firstly designs arithmetic membranes without priority rules for basic arithmetic operations, and then proposes an algorithm to construct expression P systems based on several of such membranes after designing synchronous and asynchronous transmission strategies among the *** any arithmetic expression, an expression P system can be built to evaluate it effectively. Finally, we discuss different parallelism strategies through which different expression P systems can be built for an arithmetic expression.

关键词： Membrane computing Cell-like P systems Arithmetic operations Expression P systems

The quantum cocktail party problem

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Science China(Physics,Mechanics & Astronomy) 2020年第5期63卷 2-5页

作者： Xiao Liang YaDong Wu hui Zhai Institute for Advanced Study Tsinghua UniversityBeijing 100084China Laboratory of Quantum Information University of Science and Technology of ChinoHefei 230026China

The cocktail party problem refers to the phenomenon that the brain of a listener can focus on a single voice while filtering out a range of other voices in a multi-talker situation,say,in a cocktail party[1].This selective attention problem was firstly defined as the"cocktail party problem"(CPP)by Cherry[2]in *** recent years,machine-learning based approaches to solve the CPP were essential for many industrial applications such as automated speech *** independent component analysis(ICA)is such an algorithm particularly suitable for the *** CPP also has applications in physical science such as astrophysics data analysis[3,4].

关键词： quantum problem filtering

Candidate chiral nuclei in bromine isotopes based on triaxial relativistic mean field theory

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Science China(Physics,Mechanics & Astronomy) 2019年第1期62卷 56-62页

作者： Bin Qi hui Jia Chen Liu ShouYu Wang Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and Physics Institute of Space Sciences Shandong University

Following the observation of candidate chiral doublet bands in ^(78,80)Br, triaxial deformations with corresponding configurations in odd-odd bromine isotopes have been investigated using adiabatic and configuration-fixed constrained triaxial relativistic-meanfield calculations with an aim of finding the boundary of chirality in the chain of Br isotopes. Several minima with triaxial deformation and the proper particle-hole configuration were obtained in ^(74,76,78,80,82)Br, where the chiral doublet bands have the possibility of occurrence. Furthermore, the possible existence of multiple chiral doublet(MχD) bands is demonstrated in ^(74,76,78,80,82)*** to explore the chirality and MχD properties of Br isotopes are conducted to verify the predictions.

关键词： chiral doublet bands relativistic mean field bromine isotopes

Supercapacitor electrode based on few-layer h-BNNSs/rGO composite for wide-temperature-range operation with robust stable cycling performance

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International Journal of Minerals,Metallurgy and Materials 2020年第2期27卷 220-231页

作者： Tao Yang hui-juan Liu Fan Bai En-hui Wang Jun-hong Chen Kuo-Chih Chou Xin-mei Hou Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

Currently,developing supercapacitors with robust cycle stability and suitability for wide-temperature-range operations is still a huge *** the present work,few-layer hexagonal boron nitride nanosheets(h-BNNSs)with a thickness of 2−4 atomic layers were fabricated via vacuum freeze-drying and ***,the h-BNNSs/reduced graphene oxide(rGO)composite were further prepared using a hydrothermal *** to the combination of two two-dimensional(2D)van der Waals-bonded materials,the as-prepared h-BNNSs/rGO electrode exhibited robustness to wide-temperature-range operations from−10 to 50℃.When the electrodes worked in a neutral aqueous electrolyte(1 M Na2SO4),they showed a great stable cycling performance with almost 107%reservation of the initial capacitance at 0℃ and 111% at 50℃ for 5000 charge−discharge cycles.

关键词： few-layer hexagonal boron nitride wide-temperature-range operation cycling performance

The effect of impeller slot jet on centrifugal pump performance

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Journal of Hydrodynamics 2019年第4期31卷 733-739页

作者： Ren-hui Zhang Li-chen Yun Jing Li School of Energy and Power Engineering Lanzhou University of Technology Lanzhou 730050China China Key Laboratory of Fluid Machinery and Systems Lanzhou University of Technology Lanzhou 730050 China

To improve the cavitation performance of the centrifugal pump, a new kind of centrifugal pump impeller with slot is proposed. The slot is on the impeller shroud near the suction side of the blade leading edge. So, the fluid with high energy in the impeller front side chamber is drained to the lowest pressure area. The jet flow would compensate the blade inlet flow with a certain energy. With numerical simulations, the pump's inner flows for 5 different slot sizes and their hydraulic performances are compared with those of the prototype pump. The slot jet would result in the increase of the impeller flow rate and the volute area ratio, leading to the head decrease within the whole flow rate range. The slot jet can suppress the reverse flow remarkably at a low flow rate, and the pump efficiency is improved. The slot jet improves the pump cavitation performance effectively, especially at a low flow rate. To some extent, the smaller the slot size is, the better the pump cavitation performance is. The cavitation performance of the slot impeller with a size of 2 mmx 1.75 mm is much better than that of the prototype impeller. Compared with the prototype impeller, the lowest pressure near the slot impeller blade inlet and even the pressure in all forepart regions are improved significantly. The slot impeller is shown to be effective in suppressing the cavitation, and the available net positive suction head is improved.

关键词： Centrifugal pump slot impeller slot jet cavitation performance circulation flow

Mitigation of the amplitude and celerity of dam break shock wave using combination of groyne and vertical pier

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Journal of Mountain Science 2020年第6期17卷 1452-1461页

作者： FAN Ji-hui GALOIE Majid MOTAMEDI Artemis Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China Civil Engineering Department Imam Khomeini International UniversityQazvin 34148-96818Iran Civil Engineering Department Technical University of Buein ZahraImam Khomeini BlvdBuein ZahraQazvin ***Iran

This paper aims to numerically investigate the impact of the combination of groynes and vertical piers on mitigating the amplitude and celerity of dam break ***,a robust numerical model based on the Finite Volume Method(FVM)with the Harten,Lax and van leer(HLL)approximate Reimann’s solver’s technique is developed and validated with other research *** many different scenarios including group of piers,group of groynes with different shapes and combination of groynes and piers are considered for dam break flow *** final results showed that group of piers alone or group of groynes alone have no significant effects on the wave-front depth and celerity but,combination of L-head groyne with piers can decrease the amplitude and celerity of the dam break wavefront or flood *** this case,a blockage zone between the groynes and intensive backwater effects behind them were observed.

关键词： Dam break shock wave HLL(Harten,Lax and van leer) Finite Volume Method Groyne Flood wave damping Flood management

Dyes adsorption using a synthetic carboxymethyl cellulose-acrylic acid adsorbent

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Journal of Environmental Sciences 2014年第5期26卷 1203-1211页

作者： Genlin Zhang Lijuan Yi hui Deng Ping Sun School of Chemistry and Chemical Engineering Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan Shihezi University

Removal of noxious dyes is gaining public and technological attention. Herein grafting polymerization was employed to produce a novel adsorbent using acrylic acid and carboxymethyl cellulose for dye removal. Scanning electron microscopy and Fourier-transform infrared spectroscopy verified the adsorbent formed under optimized reaction conditions. The removal ratio of adsorbent to Methyl Orange, Disperse Blue 2BLN and malachite green chloride reached to 84.2%, 79.6% and 99.9%, respectively. The greater agreement between the calculated and experimental results suggested that pseudo second-order kinetic model better represents the kinetic adsorption data. Equilibrium adsorptions of dyes were better explained by the Temkin isotherm. The results implied that this new cellulose-based absorbent had the universaiity for removal of dyes through the chemical adsorption mechanism.

关键词： adsorption dye grafting polymerization carboxymethyl cellulose acrylic acid