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ECO-HYDRAULICS TECHNIQUES FOR CONTROLLING EUTROPHICATION OF SMALL SCENERY LAKES-A CASE STUDY OF LUDAO LAKE IN SHANGHAI

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Journal of Hydrodynamics 2007年第6期19卷 776-783页

作者： YIN Hai-long xu zu-xin YAO Yi-jun HUANG Shen-fa College of Environmental Science and Engineering Tongji University Shanghai 200092 China Shanghai Academy of Environmental Sciences Shanghai 200233 China

The Ludao Lake with an area of 0.86 km2 and 50% water surface ratio, was taken as an example to study the eco-hydraulics techniques for preventing lake eutrophication. Besides external water inflow and outflow, the term related to internal local flow circulation was added in the continuity equation of two-dimensional horizontal hydrodynamic model, and further the hydrodynamic model was calibrated by the scenario of no water exchange. The velocity of 0.2 m/s was suggested to be the critical velocity of controlling algal bloom. To achieve the critical velocity in the whole lake, three factors were analyzed, which are wind, artificial external inflow augmentation and internal local flow disturbance by pump circulation. It is found that the role of wind can be disregarded. For the eco-hydraulics technique of external lake water inflow augmentation, the water flowing route should be firstly optimized, further, the lake inflow has a critical value under specified water level due to the narrow inlets, so the whole lake is difficult to reach the critical velocity to prevent algal bloom, and a combination of external inflow augmentation and internal local flowing disturbance should be considered. Simulation results show that the combination of external water inflow augmentation and internal local flow disturbance requires less eco-flow to achieve the global critical velocity than the sole internal local flow disturbance, for the Ludao Lake, the former requires total eco-flow of 25 m3/s, which reduces by 50% than the latter requiring total eco-flow of 52 m3/s.

关键词： eutrophication eco-hydraulics algal bloom,hydrodynamic model

Geometric Realization of Adams Maps

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Acta Mathematica Sinica,English Series 2011年第5期27卷 863-870页

作者： Xian zu LIN Institute of Mathematics Chinese Academy of Sciences Beijing 100190 P. R. China

Let 6/P be a homogenous space with G a compact connected Lie group and P a connected subgroup of G of equal rank. As the rational cohomology ring of G/P is concentrated in even dimen- sions, for an integer k we can define the Adams map of type k to be lk ： H^＊（G/P,Q）→ H^＊（G/P,Q）, lk（u） = k^iu, u ∈ H^2i（G/P,Q）. We show that if k is prime to the order of the Weyl group of G2 then lk can be induced by a self map of G/P. We also obtain results which imply the condition that k is prime to the order of the Weyl group of G is necessary.

关键词： Homogenous space self map Adams map

Photoreflectance system based on vacuum ultraviolet laser at 177.3 nm

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Chinese Physics B 2022年第11期31卷 100-105页

作者： Wei-Xia Luo xue-Lu Liu Xiang-dong Luo Feng Yang Shen-Jin Zhang Qin-Jun Peng zu-Yan xu Ping-Heng Tan State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of Sciences(CAS)Beijing 100083China Center of Materials Science and Optoelectronics Engineering&CAS Center of Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100049China Jiangsu Key Laboratory of ASIC Nantong UniversityNantong 226019China Key Laboratory of Solid State Laser Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China Key Laboratory of Function Crystal and Laser Technology Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China

Photoreflectance(PR)spectroscopy is a powerful and non-destructive experimental technique to explore interband transitions of *** most PR systems,the photon energy of the pumping beam is usually chosen to be higher than the bandgap energy of the *** the best of our knowledge,the highest energy of pumping laser in reported PR systems is 5.08 eV(244 nm),not yet in the vacuum ultraviolet(VUV)*** this work,we report the design and construction of a PR system pumped by VUV laser of 7.0 eV(177.3 nm).At the same time,dual-modulated technique is applied and a dual channel lock-in-amplifier is integrated into the system for efficient PR *** system’s performance is verified by the PR spectroscopy measurement of well-studied semiconductors,which testifies its ability to probe critical-point energies of the electronic band in semiconductors from ultraviolet to near-infrared spectral region.

关键词： photoreflectance spectroscopy vacuum ultraviolet laser electronic band structure critical points of electron density of states

Halo-like Structures Observed in ^(209)Pb

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Chinese Physics Letters 2001年第8期18卷 1024-1026页

作者： LIU zu-Hua China Institute of Atomic Energy Beijing 102413

The density distributions of the last neutron in ^(209)Pb wereinvestigated by analysis of the ^(208)Pb(d,p)^(209)Pb transfer reactions at 8 *** results show that the last neutron in the 2d_(5/2),3s_(1/2),1g_(7/2) and 2d_(3/2) states is present with appreciable probability at distances much larger than the core ***,these states should be the neutron halo or skin ***,the density distributions extracted illustrate that there is intrinsic relationship between the node number of state and the halo formation.

关键词： formation. states. radius.

Flow patterns and critical criteria of thermally stratified shear flow in braided rivers

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Water Science and Engineering 2017年第3期10卷 225-235页

作者： Li Gu Qiu-lan Li Bo Dai zu-lin Hua Xiao-dong Liu Ke-jian Chu Department of Civil and Environmental Engineering University of AlbertaEdmonton T6G 2R3Canada Key Laboratory of Integrated Regulation and Resource Development of Shallow Lakes Ministry of EducationHohai UniversityNanjing 210098China Zhenjiang Urban Planning and Design Institute Zhenjiang 212000China Jiangsu Transportation Institute Nanjing 210098China National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Hohai UniversityNanjing 210098China

Flow characteristics of thermally stratified shear flow in braided rivers are particularly complicated and poorly understood. In this study, a series of typical flow patterns was examined and their critical criteria were determined. Four flow patterns were identified: mixed, locally unstable, continuously stratified, and two-layer flow. Temperature distributions of the four types of flow patterns were analyzed and *** critical Froude numbers for unstable flow, FDcr1, and stable flow, FDcr2, were determined to be 6 and 1, respectively, and comparison of FDcr1 and FDcr2 to the peak Froude numbers, FD1 at the outer bank and FD2 at the inner bank along the anabranch, allowed the flow patterns to be assessed. Then, a discriminant based on initial Jeffreys-Keulegan stability parameters was established to distinguish the flow stages from twolayer flow to completely mixed flow. It is indicated that the three critical Jeffreys-Keulegan parameters increased with the diversion angle of braided rivers. Results also show that, compared to the stratified flow in straight and curved channels, it was more difficult for braided stratified flow to maintain as two-layer flow, and it more easily became mixed flow. Consequently, empirical expressions for stability criteria of the thermally stratified shear flow in braided rivers are presented.

关键词： Braided river Critical criterion Empirical formula Flow pattern Temperature distribution Thermally stratified flow

Serum ceruloplasmin can predict liver fibrosis in hepatitis B virusinfected patients

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World Journal of Gastroenterology 2020年第27期26卷 3952-3962页

作者： Na-Ling Kang Jie-Min Zhang Meng-Xin Lin xu-dong Chen zu-Xiong Huang Yue-Yong Zhu Yu-Rui Liu Da-Wu Zeng Liver Center The First Affiliated HospitalFujian Medical UniversityFuzhou 350005Fujian ProvinceChina Department of Pharmacy The First Affiliated HospitalFujian Medical UniversityFuzhou 350005Fujian ProvinceChina Department of Infectious Diseases The First Hospital of Quanzhou Affiliated with Fujian Medical UniversityQuanzhou 362000Fujian ProvinceChina Department of Gastroenterology the 910th Hospital of the People's Liberation ArmyQuanzhou 362000Fujian ProvinceChina Hepatology Mengchao Hepatobiliary Hospital of Fujian Medical UniversityFuzhou 350005Fujian ProvinceChina

BACKGROUND The presence of significant liver fibrosis in hepatitis B virus(HBV)-infected individuals with persistently normal serum alanine aminotransferase(PNALT)levels is a strong indicator for initiating antiviral *** ceruloplasmin(CP)is negatively correlated with liver fibrosis in HBV-infected *** To examine the potential value of serum CP and develop a noninvasive index including CP to assess significant fibrosis among HBV-infected individuals with *** Two hundred and seventy-five HBV-infected individuals with PNALT were retrospectively *** association between CP and fibrotic stages was statistically analyzed.A predictive index including CP[Ceruloplasmin hepatitis B virus(CPHBV)]was constructed to predict significant fibrosis and compared to previously reported *** Serum CP had an inverse correlation with liver fibrosis(r=-0.600).Using CP,the areas under the curves(AUCs)to predict significant fibrosis,advanced fibrosis,and cirrhosis were 0.774,0.812,and 0.853,*** CPHBV model was developed using CP,platelets(PLT),and HBsAg levels to predict significant *** AUCs of this model to predict significant fibrosis,advanced fibrosis,and cirrhosis were 0.842,0.920,and 0.904,*** was superior to previous models like the aspartate aminotransferase(AST)-to-PLT ratio index,Fibrosis-4 score,gamma-glutamyl transpeptidase-to-PLT ratio,Forn’s score,and S-index in predicting significant fibrosis in HBV-infected individuals with *** CPHBV could accurately predict liver fibrosis in HBV-infected individuals with ***,CPHBV can be a valuable tool for antiviral treatment decisions.

关键词： Ceruloplasmin Liver fibrosis Chronic hepatitis B infection Serum alanine aminotransferase Noninvasive model Receiver-operating characteristic

A class of estimators of the mean survival time from interval censored data with application to linear regression

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Applied Mathematics(A Journal of Chinese Universities) 2008年第4期23卷 377-390页

作者： ZHENG zu-kang Dept. of Statist. School of Management Fudan Univ. Shanghai 200433 China

A class of estimators of the mean survival time with interval censored data are studied by unbiased transformation method. The estimators are constructed based on the observations to ensure unbiasedness in the sense that the estimators in a certain class have the same expectation as the mean survival time. The estimators have good properties such as strong consistency （with the rate of O（n^-1/1 （log log n）^1/2）） and asymptotic normality. The application to linear regression is considered and the simulation reports are given.

关键词： interval censored data linear regression

Characteristics of combustion zone and evolution of mineral phases along bed height in ore sintering

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International Journal of Minerals,Metallurgy and Materials 2017年第10期24卷 1087-1095页

作者： Yao-zu Wang Jian-liang Zhang Zheng-jian Liu Ya-peng Zhang dong-hui Liu Yi-ran Liu School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

Quantitative parameters of bed combustion, including the thickness of the combustion zone(TCZ), the maximum temperature of the combustion zone(MTCZ), and the bed shrinkage, were characterized through a series of sinter pot tests in transparent quartz pots. The results showed that TCZ first ascended and then descended as the sintering process proceeded. The sintering process was divided into four stages according to the variation rate of the TCZ. A "relative-coordinate" method was developed to obtain the actual reaction temperature of sinter along the height direction. With increasing the sintering temperature, the reactants transformed and entered into liquid phases. The mineral composition and microstructure of the sinter were characterized through X-ray diffraction and scanning electron microscopy–energy-dispersive X-ray spectroscopy. Liquid phases with greater Fe and Al contents were more likely to form acicular-like silico-ferrite of calcium and aluminum after crystallization because of the outward spread of Al, which led to a better fluidity of the liquid. An evolution mechanism of "solid-state reaction—liquid phases formation—crystallization" of the mineral phases is proposed.

关键词： flame front mineral phases sintering evolution mechanism transparent quartz pots

Theoretical Research on a D-Band Traveling Wave Extended Interaction Amplifier

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Chinese Journal of Electronics 2024年第6期33卷 1487-1491页

作者： Zhongtao CUI xuesong YUAN Xiaotao xu dongrui CHEN Yifan zu Matthew Thomas Cole Qingyun CHEN Yang YAN Terahertz Science and Technology Key Laboratory of Sichuan Province School of Electronic Science and EngineeringUniversity of Electronic Science and Technology of China Department of Electronic and Electrical Engineering University of Bath

A traveling-wave, extended interaction amplifier is herein investigated for use in millimeter-wave and terahertz amplification sources. By placing engineered extended interaction cavities between the traveling wave structures, higher gain is obtained with a shorter high frequency circuit, compared with conventional traveling wave tubes architectures. The bandwidth of the device is significantly increased relative to extended interaction klystrons. A Dband beam wave interaction circuit of 26 mm long has been designed. Particle-in-cell simulations at 21.5-kV operating voltage, 0.3-A beam current, and 5-mW input power show that the maximum output power reaches 351 W, with a gain of 48.4 dB and 3-dB bandwidth of 1.42 GHz.

关键词： Particle beams Millimeter wave circuits Traveling wave tubes Power amplifiers Bandwidth Voltage Terahertz radiation Gain Power generation Magnetic circuits