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An ecological hydraulic radius approach to estimate the instream ecological water requirement

Progress in Natural Science:Materials International 2007年第3期17卷 320-327页

作者： LIU Changming and MEN Baohui ( Key Laboratory of Water Cycle and Related Land Surface Process, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, beijing 100101, china Key Laboratory of Water and Sediment Sciences, Ministry of Education & Water Sciences College, beijing normal university, beijing 100875. china {4. of Hydraulic and Hydropower Engineering, North china Electric Power university, beijing 102206, china) [a]Key Laboratory of Water Cycle and Related Land Surface Process Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China [b]Key Laboratory of Water and Sediment Sciences Ministry of Education & Water Sciences Gllege Beijing Noirnal University Beijing China [c]Departhent of Hydraulic and Hydropower Engineering North China Elecfric Power University Beijing China

This essay defines the concepts of ecological flow velocity as well as ecological hydraulic radius (EHR) and proposes an ecological hydraulic radius approach (EHRA) which considers both the watercourse information (including hydraulic radius, roughness coefficient and hydraulic gradient) and the required stream velocity necessary for maintenance of certain ecological functions all together. The key parameter of EHRA is to fix the watercourse cross-sectional flow area corresponding to EHR, by which the relation between parabola shaped cross-sectional flow area and hydraulic radius is deduced. The EHRA not only meets the requirement of flow velocity for adequate fish spawning migration, but also is applicable to the ecological flows in regard with other ecological issues (such as the calculation of the instream flow requirements for transporting sediment and for pollution self-purification, etc.). This essay has illuminated the computational process taking the estimation of ecological water requirement of Zhuba Hydrologyical Station watercourse in Niqu branch of the Yalong River as an example. Additionally, we compare EHRA with Tennant approach. The result shows that the Zhuba Hydrological Station ecological water requirement calculated by EHRA lies between the minimum and favorable ecological water requirement calculated by the Tennant approach. This is due to the fact that the ecological flow velocity (such as the fish spawning migration flow velocity) was taken into consideration, producing results applicable to the practical situation.

关键词： ecological flow flow velocity cross-sectional flow area ecological hydraulic radius (HER) instreamecological water requirement.

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N-widths on the classes of multivariate bandlimited functions

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Progress in Natural Science:Materials International 2004年第10期14卷 23-26页

作者： FANG Gensun and LONG Jingfan (department of Mathematics,beijing normal university,beijing100875.china) Received January30,2004 beijing normal Univ Dept Math Beijing 100875 Peoples R China

In this paper,the tight order on the n-widths of the classes of multivariate bandlimited functions in L p ( d ),1

关键词： n-width multivariate bandlimited function sampling theorem

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A COUPLED MODEL OF HYDRODYNAMICS AND WATER QUALITY FOR YUQIAO RESERVOIR IN HAIHE RIVER BASIN

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Journal of Hydrodynamics 2008年第5期20卷 574-582页

作者： LIU Xiao-bo PENG Wen-qi HE Guo-jian LIU Jing-ling WANG Yu-chun School of Environment Beijing Normal University Beijing 100875 China department of Water Environment China Institute of Water Resources and Hydropower Research Beijing100038 China department of Hydraulic Engineering State Key Laboratory of Hydroscience and Engineering TsinghuaUniversity Beijing 100084 China

In order to simulate the characteristics of hydrodynamic field and mass transport processes in the Yuqiao Reservoir （YQR）, a 2-D coupled model of hydrodynamics and water quality was developed, and the water-quality related state variables in this model included CODMn, TN and TP. The hydrodynamic model was driven by employing observed winds and daily measured flow data to simulate the seasonal water cycle of the reservoir. The simulation of the mass transport and transformation processes of CODMn, TN and TP was based on the unsteady diffusion equations, driven by observed meteorological forcing and external loadings, with the fluxes form the bottom of reservoir and the plant photosynthesis and respiration as internal sources and sinks. A finite volume method and Alternating Direction Implicit （ADI） scheme were used to solve these equations. The model was calibrated and verified by using the data observed from YQR in two different years. The results showed that in YQR, the wind-driven current was an important style of lake current, while the concentration of water quality item was decreasing from east to west because of the external pollutant loadings. There was a good agreement between the simulated and measured values, with the minimal calculation error percent of 0.1% and 2.6% and the mean error percent of 4..0% and 51.2% for TN and TP separately. The simulation also showed that, in YQR, the convection was the main process in estuaries of inflow river, and diffusion and biochemical processes dominate in center of reservoir. So it was necessary to build a pre-pond to reduce the external loadings into the reservoir.

关键词： model simulation Yuqiao Reservoir (YQR) wind driven current water quality

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Correlation between inhibition of calcium-dependent apoptosis by cyclosporin A and calcium transportation in HL-60 cells

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Cell Research 1996年第1期6卷 23-30页

作者： HUANG QI QING MING FANG HONG QING ZHANG SHAO BAI XUE(department of Biology, beijing normal university, beijing 100875. china.) department of Biology Beijing Normal University Beijing China

Both calcium ionophore A23187 and endoplasmic reticulum Ca2+- ATPase inhibitor thapsigargin (Tg) could increase intracellular free calcium concentration and induce apoptosis in some cell lines. In the present study, we found that HL-60 cells treated with A23187 (1μg/ml) for 4.h or with Tg (0.5μg/ml) for 2 h showed typical characteristics of apoptosis. Pretreatment with nontoxic concentration of cyclosporin A (CsA) (1μg/ml) Could block these effects. Flow cytometric analysis of intracellular Ca2+ after staining with fluo-3 AM showed that CsA did not prevent the increase of intracellular calcium induced by A23187 or Tg, but it could maintain the high level of intracellular Ca2+ for a long time. These results suggest that CsA may prevent calcium- induced apoptosis by blocking the transportation of Ca2+ in HL-60cells.

关键词： Cyclosporin A calcium ionophore A23187 thapsigargin apoptosis intracellular calcium

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Calculation of the Canonical Rate Constant for the Nonadiabatic Trapping Model Based on Unified Statistical Theory:A Test on The Exchange Reaction H_2+H

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Chinese Chemical Letters 1998年第2期9卷 177-179页

作者： Shu Xia YIN Yan WANG and Wen Lin FENG(Chemistry department, Bejing normal university, beijing {4. beijing normal Univ Dept Chem Beijing 100875 Peoples R China

A new approach was employed to calculate the canonical (thermal) rate constant basedon unified statistical theory. All information for the calculation was obtained from ab initio meth-ods. The flux integral for any point of reaction coordinate was calculated by counting the numberof quantum states and applied to determine the dividing surfaces along the intrinsic reaction coor-dinate (IRC). The classical exchange reaction H2+H, as an example, was investigated. The IRC forthe reaction has been traced and detailed information of IRC was carried out at the QCISD/6-311 G** level .The calculated rate constants are well consistent with the experimental results.

关键词： unified statistical theory intrinsic reaction coordinate (IRC) canonical rate constants

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A Survey and Statistics of Interstellar OH and H_2O Masers

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Chinese Journal of Astronomy and Astrophysics 2005年第2期5卷 175-183页

作者： Han-PingLiu J.R.Forster JinSun departmentofphysics BeijingNormalUniversityBeijing100875 universityofCalifornia BerkeleyandHatCreekRadioObservatory42231BidwellRoadHatCreekCA96040 departmentofAstronomy BeijingNormalUniversityBeijing100875

We present a statistical analysis of a sky survey of interstellar H2O and OH masers. These masers can be classified into three categories: isolated H2O masers, isolated OH masers, and simple OH/H2O maser associations. The total number of sources in each category is of the same order of magnitude, and as an evolutionary phase they can maintain ~ 105 yr. An improved radiative pumping mechanism is proposed. This model avoids some of the deficiencies of previous radiative models, such as shortage of exciting photons. The statistical results obtained from the survey can be interpreted by the new mechanism together with the evolutionary model in which the gravitational force of the central stellar objects is responsible for the HII region.

关键词： surveys masers radiation mechanism: non-thermal HII regions

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First-principles calculations on implanted TiO_2 by 3d transition metal ions

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Science china(physics,Mechanics & Astronomy) 2009年第6期52卷 838-842页

作者： HOU XingGang1,2, HUANG MeiDong1, WU XiaoLing2 & LIU AnDong2 1 department of physics, Tianjin normal university, Tianjin 300387, {4. 2 Key Laboratory of Beam Technology and Material Modification of Ministry of Education, beijing normal university, beijing 100875. china department of physics Tianjin Normal University Tianjin 300387 China Key Laboratory of Beam Technology and Material Modification of Ministry of Education Beijing Normal University Beijing 100875 China

3d transition metal (V, Cr and Fe) ions are implanted into TiO2 by the method of metal ion implantation. The electronic band structures of TiO2 films doped 3d transition metal ions have been analyzed by ab initio band calculations based on a self-consistent full-potential linearized augmented plane-wave method within the first-principle formalism. Influence of implantation on TiO2 films is examined by the method of UV-visible spectrometry. The results of experiment and calculation show that the optical band gap of TiO2 films is narrowed by ion implantation. The calculation shows that the 3d state of V, Cr and Fe ions plays a significant role in red shift of UV-Vis absorbance spectrum.

关键词： 3d transition metal ions implantation TiO2 FP-LAPW electronic structure

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Progress in multi-waveband observations of supernova remnants

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Progress in Natural Science:Materials International 2008年第9期18卷 1057-1062页

作者： Xuejuan Yang a,b, Fangjun Lua, Wenwu Tian c,d,* a Particle Astrophysics Center, Institute of High Energy physics, Chinese Academy of Sciences, beijing 10004., china b {4. of Astronomy, beijing normal university, beijing 100875. china c National Astronomical Observatories, Chinese Academy of Sciences, 20A Datun Road, Chaoyang District, CAS, beijing 100012, china d {4. of physics & Astronomy, university of Calgary, Alberta, Canada T2N 1N4 Particle Astrophysics Center Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China department of Astronomy Beijing Normal University Beijing 100875 China National Astronomical Observatories Chinese Academy of Sciences 20A Datun Road Chaoyang District CAS Beijing 100012 China department of physics & Astronomy University of Calgary Alberta Canada T2N 1N4

The development of observational techniques has enriched our knowledge of supernova remnants. In this paper, we review the main progresses in the last decade, including new discoveries of supernova remnants and the associated (rare type of) pulsars, nucleosynthesis, the interaction between supernova remnants and molecular clouds, dust in the supernova remnants, shock physics, and cosmic ray accelerations.

关键词： Supernova remnant Observations

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Relation between seed size in different plant species and response of their seedlings to double CO_2

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Chinese Science Bulletin 1997年第4期42卷 331-333页

作者： DING Li, ZHANG Chonghao, BAI Kezhi and KUANG Tingyun1 department of Biology, beijing normal university, beijing 100875. china 2. Institute of Botany, Chinese Academy of Sciences, beijing 100093, {4. department of Biology Beijing Normal University Beijing China Institute of Botany Chinese Academy of Sciences Beijing China

ATMOSPHERIC CO2 concentration is predicted to increase to 700μL/L by the middle of the 21st century. The impacts of raising CO2 on vegetation and ecosystem have been intensively studied. It is well known that C3 species and C4./sub> species responded much differently to double CO2. Potential enhancement of photosynthesis efficiency induced by double CO2 in C3 plants was almost 66%, but in C4./sub> plants only 4.. The response to double CO2 in C3 species might

关键词： double CO2 seed size seedling growth percentage enhancement.

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Recent progress on the structure of Ser/Thr protein phosphatases

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Science china(Life Sciences) 2008年第6期51卷 487-494页

作者： WANG BaiJing1,2, ZHANG Peng1 & WEI Qun1 1 department of Biochemistry and Molecular Biology, beijing normal university, beijing Key Laboratory, beijing 100875. china 2 School of Life Science, Changchun {4. university, Changchun 130032, china 1. department of Biochemistry and Molecular Biology Beijing Normal University Beijing Key Laboratory Beijing 100875 China 2. School of Life Science Changchun Normal University Changchun 130032 China

PP1, PP2A and PP2B, belonging to the PPP family of Ser/Thr protein phosphatases, participate in regulating many important physiological processes, such as cell cycle control, regulation of cell growth and division regulation, etc. The sequence homology between them is relatively high, and ter- tiary structure is conserved. Because of the complexity of the structure of PP2A and the diversity of its regulatory subunits, its structure is less well known than those of PP1 and PP2B. The PP2A holoen- zyme consists of a heterodimeric core enzyme, comprising a scaffolding subunit and a catalytic sub- unit, as well as a variable regulatory subunit. In this study, the subunit compositions, similarities and differences between the Ser/Thr protein phsphatases structures are summarized.

关键词： Ser/Thr phosphatases subunit composition similarities and differences crystal structure

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