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Biological control experiment of excess propagation of Cyclops for drinking water security

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Journal of Environmental Sciences 2007年第3期19卷 290-294页

作者： LIN Yao cui Fu-yi LIU Dong-mei College of Environmental Science and Engineering Hohai University Nanjing 210098 China School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China

Cyclops of zooplankton propagated excessively in eutrophic water body and could not be effectively inactivated by the conventional disinfections process like chlorination due to its stronger resistance to oxidation. In this study, an ecological project was put forward for the excess propagation control of Cyclops by stocking the filter-feeding fishes such as silver carp and bighead carp under the condition of no extraneous nutrient feeding. The results of experiments with different stocking biomass showed that the propagation of Cyclops could be controlled effectively, and the water quality was improved simultaneously by impacting on nutriment level and plankton community structure at proper stocking density of 30 g/m^3 of water. The growth of Cyclops may not be effectually controlled with lower biomass of fish （10 g）, and the natural food chain relation may be destroyed for Cyclops dying out in water while the intense stocking of 120 g per cubic meter of water. In addition, the high predator pressure may accelerate supplemental rate of nutrients from bottom sediments to water body to add the content of total nitrogen and phosphorus in water.

关键词： filter-feeding fishes Cyclops zooplankton biomanipulation water treatment

Experimental study on the size effect on the equation of state of concretes under shock loading

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Defence Technology（防务技术） 2024年第3期33卷 160-167页

作者： mei Li Jian cui Yanchao Shi Baijian Tang Xin Chen Key Laboratory of Coast Civil Structural Safety of the Ministry of Education Tianjin UniversityTianjin 300072China School of Civil Engineering Suzhou University of Science and Technology1701 Binhe RoadSuzhou 215011JiangsuChina School of Civil Engineering Tianjin UniversityTianjin 300072China

Adopting the classical theory of hydrocodes,the constitutive relations of concretes are separated into an equation of state(EoS)which describes the volumetric behavior of concrete material and a strength model which depicts the shear properties of *** experiments on the EoS of concrete is always challenging due to the technical difficulties and equipment limitations,especially for the specimen size effect on the *** some researchers investigate the shock properties of concretes by fly-plate impact tests,the specimens used in their tests are usually in one *** this paper,the fly-plate impact tests on concrete specimens with different sizes are performed to investigate the size effect on the shock properties of concrete *** mechanical background of the size effect on the shock properties are revealed,which is related to the lateral rarefaction effect and the deviatoric stress produced in the *** to the tests results,the modified EoS considering the size effect on the shock properties of concrete are proposed,which the bulk modulus of concrete is unpredicted by up to 20% if size effects are not accounted for.

关键词： Concrete Equation of state Size effect Shock wave Fly-plate impact test

Big data: the driver for innovation in databases

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National Science Review 2014年第1期1卷 27-30页

作者： Bin cui Hong mei Beng Chin Ooi School of EECS and Key Laboratory of High Conidence Software Technologies Peking University School of Computing National University of Singapore

INTRODUCTION Advances in the technology frontier have resulted in major disruptions and transformations in the enterprise-wide information technology *** the past three decades,classical database management systems have maintained a feverish pace in realizing signiicant eiciencies in dealing with the vast amount of information that needs to be maintained to model the operational characteristics of large-scale *** research and

关键词： Big data the driver for innovation in databases

A logistic model for magnetic energy storage in solar active regions

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Research in Astronomy and Astrophysics 2009年第6期9卷 687-693页

作者： Hua-Ning Wang Yan-mei cui Han He National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Space Science Research and Application Center Chinese Academy of Sciences Beijing 100080 China

Previous statistical analyses of a large number of SOHO/MDI full disk longitudinal magnetograms provided a result that demonstrated how responses of solar flares to photospheric magnetic properties can be fitted with sigmoid functions. A logistic model reveals that these fitted sigmoid functions might be related to the free energy storage process in solar active regions. Although this suggested model is rather simple, the free energy level of active regions can be estimated and the probability of a solar flare with importance over a threshold can be forecast within a given time window.

关键词： Sun photosphere -- Sun magnetic field -- Sun solar activity

Improved taylor-series location algorithm for cooperation networks

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The Journal of China Universities of Posts and Telecommunications 2007年第2期14卷 38-44页

作者： LIU Jun cui Qi-mei TAO Xiao-feng Key Laboratory of Ubiquitous Wireless Communication Beijing University of Posts and Telecommunications Beijing 100876 China

This article presents an iterative algorithm for estimating the location of the destination mobile station （DS） when some extra mobile stations around the DS are involved in and assist the base stations to complete the localization process. The proposed method is based on the taylor-series （TS） method and jointly estimates both the DS and the extra mobile stations, named reference mobile station （RS） in this article, positions simultaneously. Moreover, the time-differential-of-arrival （TDOA） measurements between DS and pairs of RSs are obtained by ultra-wide-band （UWB） signal, which is adept in accurate ranging application. According to the theoretic analysis, the Cramer-Rao lower bound （CRLB） of the modified TS algorithm reduces significantly. The actual performance, under a given simulation scenario, is enhanced by 25% at best.

关键词： UWB CRLB TS TDOA least-square (LS)

Crystal Structure of a New Cembranolide Diterpene

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Chemical Research in Chinese Universities 2002年第2期18卷 189-191页

作者： LIN cui wu SU Jing yu ZENG Long mei School of Chemistry and Chemical Engineering Zhongshan UniversityGuangzhou 510275P.R.China Department of Chemistry Guangxi UniversityNanning 530004P.R.China

A new cembranoide deterpene was isolated from the soft coral Sinularia Tenella . The crystal and chemical structure of the title compound were determined by means of spectroscopic methods and X ray diffraction analysis as ( 1R *,4R *,5S *,12S *,12R * ) 9 acetoxy cembr 8\%E\%,15(17) dien 16,4 olide. It shows a moderate cytotoxicity against P 388 and L 1210 cell lines.

关键词： Crystal structure Cembranolide diterpene X ray diffraction Sinularia tenella

Evolution of insoluble eutectic Si particles in anodic oxidation films during adipic–sulfuric acid anodizing processes of ZL114A aluminum alloys

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International Journal of Minerals,Metallurgy and Materials 2015年第3期22卷 302-308页

作者： Lei Hua Jian-hua Liu Song-mei Li mei Yu Lei Wang Yong-xin cui School of Materials Science and Engineering Beihang University Beijing Xinghang Mechanical-electrical Equipment CO. LTD.

The effects of insoluble eutectic Si particles on the growth of anodic oxide films on ZL114A aluminum alloy substrates were in- vestigated by optical microscopy （OM） and scanning electron microscopy （SEM）. The anodic oxidation was performed at 25℃ and a con- stant voltage of 15 V in a solution containing 50 g/L sulfuric acid and 10 g/L adipic acid. The thickness of the formed anodic oxidation film was approximately 7.13 μm. The interpore distance and the diameters of the major pores in the porous layer of the film were within the ap- proximate ranges of 10~20 nm and 5-10 nm, respectively. Insoluble eutectic Si particles strongly influenced the morphology of the anodic oxidation films. The anodic oxidation films exhibited minimal defects and a uniform thickness on the ZL114A substrates; in contrast, when the front of the oxide oxidation films encountered eutectic Si particles, defects such as pits and non-uniform thickness were observed, and pits were observed in the films.

关键词： aluminum alloys anodizing anodic oxidation thin films eutectic silicon particles

Much late onset of Quaternary glaciations on the Tibetan Plateau:determining the age of the Shishapangma Glaciation using cosmogenic 26Al and 10Be dating

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Science Bulletin 2018年第5期63卷 306-313页

作者： Yixin Chen Yingkui Li mei Zhang Zhijiu cui Gengnian Liu College of Urban and Environmental Sciences Peking University Beijing 100871 China Department of Geography University of Tennessee Knoxville TN 37996 USA College of Urban and Environment Science Changchun Normal University Changchun 130032 China

The onset of Quaternary glaciations is a critical event in the climate and tectonic history of the Tibetan *** Shishapangma Glaciation,defined based on the till deposit from the northern slopes of ***,has been identified as the oldest glaciation on the Tibetan ***,the timing of this glaciation has not been *** measured^(10)Be and^(26)Al concentrations of a set of boulders on top of this till and simulated their complex exposure-burial *** simulated results indicate that the formation age of this till is likely around 835.2±241.0 ka,representing the minimum timing of glacial onset on the Tibetan *** Shishapangma Glaciation is apparently much younger than the glacial onset in many other areas of the world,such as Europe and North America,and was likely driven by the coupled effect between tectonic uplift and climate cooling during the early–middle Pleistocene transition.

关键词： Glacial onset Tibetan Plateau Quaternary glaciations Cosmogenic nuclides Exposure-burial history simulation

Phenols/Al(C_(6)F_(5))_(3) Initiation Systems for Cationic Polymerizations of Isobutylene

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Chinese Journal of Polymer Science 2023年第5期41卷 713-719,I0008页

作者： Ling Cai Qi-Yuan Wang Xin-Li Liu Dong-mei cui State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Department of Polymer Science and Engineering University of Science and Technology of ChinaHefei 230026China

We report herein the cationic polymerization of isobutylene(IB)under mild conditions is realized with a new binary initiation system generated by simply mixing a Lewis super acid Al(C_(6)F_(5))_(3) and a substituted phenol(RPhOH).Polymers with medium and/or high molecular weights(M_(W)=4.9×10^(4)-27.7×10^(4) g·mol^(-1))can be obtained in toluene and temperatures from-20℃to 0℃.NMR spectrum analysis and DFT sim ulation reveals the in situ generated acidic coordinating complex Ak(C_(6)F_(5))_(3)·RPhOH is the initiating active species,which fu rther tran sformed into the ion-pair[Al(C_(6)F_(5))_(3)ORPh]^(-)[PIB]^(+)of the active intermediates upon growing IB monomers where the counter anion[Al(C_(6)F_(5))_(3)R^(O)Ph]-coordinates to the macrocation via the phenoxy *** catalyst performances are the concert effects of the steric bulkiness and electronics of the counter anion on the coordinating strength to the macrocation,which is significant to the stability of the active species.

关键词： Cationic polymerization Phenols Lewis super acid Polyisobutylene