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Progress in Natural Science:Materials International 2005年第8期15卷 713-719页

作者： YANG Yufeng*(Institute of Hydrobiology, jinan University, guangzhou {2., china) Institute of Hydrobiology Jinan University Guangzhou 510632 China

Characteristics of the zooplankton community inhabiting the sea surface microlayer (SM) and the sub-surface microlayer (SSM) are compared at six sampling stations in Daya Bay, near Shenzhen City of china during 2.cruises in 1999. This is the first study on zooplankton community in the SM in china. Results show that protozoans and nauplii are the most dominant components, accounting for 80.71% (SM) and 89.15% (SSM) of the total zooplankton in the average abundance, respectively. The densities of copepods (adult + copepodid) are higher in the SSM than in the SM. The size-frequency distributions indicate that the frequency of micro-zooplankton (2.mm) is higher in the SM (0.82.5, n=2.0) than in the SSM (0.6768, n=306). Enrichment phenomenon of zooplankton is detected in the SM at the sampling stations excluding two stations near nuclear power plants (NPP). The enrichment factor is from 1.516 to 3.364 with the average value of 2.2.7. The SM zooplankton community structure revealed in the present study is quite different from previous investigations in the Bay. Typical sea water characteristics such as turbidity, biological oxygen demand (BOD), chemical oxygen demand (COD), total nitrogen (TN), total phosphorus (TP) and chlorophyll a (Chl-a) indicate that the water quality is poorer in the SM than in the SSM.

关键词： zooplankton density sea surface microlayer subsurface microlayer Daya Bay.

ON CLASSIFICATION OF PROJECTIVE VARIETIES WITH NON-INTEGRAL NEF VALUES

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Chinese Annals of Mathematics,Series B 2001年第2期22卷 255-262页

作者： ZHAO YICAI Department of Mathematics, jinan University, guangzhou {2., china. Department of Mathematics Jinan University Guangzhou 510632 China

Let M be an n-dimensional normal projective variety with only Gorenstein, terminal, Qfactorial singularities. Let L be an ample line bundle on M. Let r denote the nef value of (M, L). The classification of (M, L) via ... 详细信息

关键词： Nef value morphism Ample line bundle Projective variety

Impact of EnKF assimilating Himawari-8 all-sky infrared radiance on the forecasting of a warm-sector rainstorm event

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Science china Earth Sciences 2024年第10期67卷 3110-3127页

作者： Shanshan LOU Lei ZHU Xuexing QIU guangzhou CHEN Song YUAN Shengnan ZHOU Anhui Meteorological Observatory Hefei 230031China Key Laboratory of Meteorological Disaster Ministry of Education(KLME)Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Joint International Research Laboratory of Climate and Environment Change(ILCEC)Nanjing University of Information Science&TechnologyNanjing 210044China Huaihe River Basin Meteorological Center Hefei 230031China Shouxian National Climatology Observatory Huaihe River Basin Typical Farm Eco-Meteorological Experiment Field of CMAShouxian National Comprehensive Meteorological Observation Special Experimental OutfieldShouxian 232200China Anhui Province Key Laboratory of Atmospheric Science and Satellite Remote Sensing Hefei 230031China

Warm-sector rainstorms are highly localized events, with weather systems and triggering mechanisms are not obvious,leading to limited forecasting capabilities in numerical models. Based on the ensemble Kalman filter(PSU-En KF) assimilation system and the regional mesoscale model WRF, this study conducted a simulation experiment assimilating all-sky infrared(IR)radiance for a warm-sector rainstorm in East china and investigated the positive impact of assimilating the Himawari-8 moisture channel all-sky IR radiance on the forecast of the rainstorm. Results indicate that hourly cycling assimilation of all-sky IR radiance can significantly improve the forecast accuracy of this warm-sector rainstorm. There is a notable increase in the Threat Score(TS), with the simulated location and intensity of the 3-hour precipitation aligning more closely with observations. These improvements result from the assimilation of cloud-affected radiance, which introduces more mesoscale convective information into the model's initial fields. The adjustments include enhancements to the moisture field, such as increased humidity and moisture transport, and modifications to the wind field, including the intrusion of mid-level cold air and the strengthening of lowlevel convergent shear. These factors are critical in improving the forecast of this warm-sector rainstorm event.

关键词： Ensemble Kalman filter WRF model Himawari-8 All-sky radiance Warm-sector rainstorm

Spatial Carrier Bi-frequency Fourier Transform Profilometry for the 3-D Shape Measurement of Object with Discontinuous Height Steps

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Chinese Journal of Lasers 2000年第2期9卷 121-127页

作者： ZHONG Jingang DI Hongwei ZHANG Yonglin (Deportment of Physics, jinan University, guangzhou {2., china ) 济南大学广东广州

The combination of shearing interferometer, Fourier-transform profilometry, phase unwrapping by lockup table method has resulted in a new and more powerful method of measuring surface profile. The technique permits the three-dimensional shape measurement of objects that have discontinuous height steps. Experimental results have demonstrated the validity of the principle.

关键词： profilometry bi-frequency phase unwrapping discontinuous height step

A temporal framework for building up of healthy soils

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Frontiers of Agricultural Science and Engineering 2024年第2期11卷 292-296页

作者： Junling ZHANG Jiangzhou ZHANG Yunlong ZHANG guangzhou WANG State Key Laboratory of Nutrient Use and Management College of Resources and Environmental SciencesNational Academy of Agriculture Green DevelopmentChina Agricultural UniversityBeijing 100193China Inner Mongolia Key Laboratory of Soil Quality and Nutrient Resources College of GrasslandResources and EnvironmentInner Mongolia Agricultural UniversityHohhot 010018China Key Laboratory of Grassland Management and Utilization Ministry of Agriculture and Rural Affairs of the People’s Republic of ChinaCollege of Grassland Science and TechnologyChina Agricultural UniversityBeijing 100193China

Healthy soils are vital for the diverse services provided by ecosystems to human society~[1], such as provisioning(food,fiber, timber, and fuel), regulation(climate, disease, and natural hazards), waste treatment, nutrient cycling, and cultural services. Soil has a three phase system and the interactions between soil chemical, biological, and physical attributes determine functions(hydraulic, thermal, and gas fluxes).

关键词： soils soil cycling

Determining the Optimal Solution Set for Linear Fractional Programming

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Journal of Systems Engineering and Electronics 2002年第3期13卷 40-45页

作者： Xue Shengjia Management College, jinan University,guangzhou {2., P.R. china Management College Jinan University Guangzhou 510632 P. R. China

The structure of the optimal solution set is derived for linear fractional programming with the representation theorem of polyhedral sets. Based on an adaptation of the convex simplex method credited to Gilmore and Gomory, we give the uniqueness condition of optimal solution and the computational procedures to find all optimal solutions if the uniqueness condition is not satisfied. Finally, an illustrative example is also given.

关键词： Optimal systems Optimization

Intein-mediated Rapid Purification of Recombinant Human Pituitary Adenylate Cyclase Activating Polypeptide

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Acta Biochimica et Biophysica Sinica 2004年第11期36卷 759-766页

作者： Rong-jie YU, An HONG, Yun DAI, and Yuan GAOBio-engineering Institute of jinan University, guangzhou {2., china Bio-engineering Institute of jinan University Guangzhou 510632 China

In order to obtain the recombinant human PACAP efficiently by intein-mediated single column purification, a gene encoding human PACAP was synthesized and cloned into Escherichia coli expression vector pKYB. The recomb... 详细信息

关键词： intein recombinant human pituitary adenylate cyclase activating peptide (rhPACAP) purification

Soils for food security

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Frontiers of Agricultural Science and Engineering 2024年第2期11卷 213-215页

作者： guangzhou WANG Qichao ZHU Junling ZHANG State Key Laboratory of Nutrient Use and Management National Academy of Agriculture Green DevelopmentCollege of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China

Food security is among the most fundamental of national interests and productive farmland is essential for secure grain *** the increase of agricultural intensification and the impact of global climate change,the soil... 详细信息

关键词： farmland security earth

Accurate determination of the plate model based on CCD images with different orientations

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Chinese Science Bulletin 2010年第9期55卷 791-796页

作者： PENG QingYu1,2.3,4 & FAN LiangYan1,2.3,4 1 Joint Laboratory for Astrometry, Dynamics and Space Science, jinan University, guangzhou {2., china 2.Department of Computer Science, jinan University, guangzhou {2., china 3 Key Laboratory of Optoelectronic Information and Sensing Technologies of Guangdong Higher Educational Institutes, jinan University, guangzhou {2., china 4 Joint Laboratory for Optical Astronomy, Chinese Academy of Sciences, Kunming 650011, china Joint Laboratory for Astrometry Dynamics and Space Science Jinan University Guangzhou China Department of Computer Science Jinan University Guangzhou China Key Laboratory of Optoelectronic Information and Sensing Technologies of Guangdong Higher Educational Institutes Jinan University Guangzhou China Joint Laboratory for Optical Astronomy Chinese Academy of Sciences Kunming China

The images of the open cluster NGC2.68 are taken using the newly-fitted 2.×2. CCD attached to the 1-m telescope at the Yun-nan Observatory with two different orientations. After the catalogue position of a star from UCAC2.is compared with its corresponding measured position, a surprising result shows that a small field of view (about 7′×7′) exhibits an obvious distortion. Spe-cifically, the polynomial between the standard coordinate (ξ,η) and its corresponding measured one (x,y) for a star in each field of view has significant terms as high as 4th order. Accordingly, the positional measurement accuracy of a bright UCAC2.star can be derived as well as ~7 mas in each direction (60 s of exposure time and near the zenith). This new finding would be important for a CCD image to deliver a highly accurate position in its whole field of view.

关键词： CCD imaging field distortion positional measurement image analysis

The Stamping Formability of AZ31 Magnesium Alloy Sheet Improved by Equal-channel Angular Pressing

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Journal of Wuhan University of Technology(Materials Science) 2010年第2期25卷 234-237页

作者：刘英 Department of Material Science and Engineering Jinan University

Equal channel angular pressing （ECAP） processing and annealing were applied to the AZ31 magnesium alloy sheets to evaluate the potential improvement in the mechanical properties and formability. The ECAP experiment was conducted at 300 ℃ in a die having an included angle of 90o between two channels by the BCZ route with the sheets rotated by 90°about the normal axis of plate plane. The tensile tests and conical cup tests were conducted at various temperatures from 2. to 2.0 ℃. The experimental results indicated that improving the working temperatures could lead to the soft in the material and the enhancement of ductility. Comparatively, the ECAPed AZ31 alloy sheets showed the lower yield strength and smaller conical cup value （CCV） than the unECAPed counterpart in the room temperature. The difference in yield strength between them became small in the elevated temperature, but the ECAPed samples still had the smaller CCV value, implying the improved formability. The texture of the AZ31 alloy sheets could be modified by ECAP and the decrease in the yield strength and more uniform deformation realized in the material, so the formability of AZ31 alloy sheets was improved.

关键词： AZ31 magnesium alloy sheets equal-channel angular pressing mechanical properties conical cup value (CCV)