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A general multi-objective programming model for minimum ecological flow or water level of inland water bodies

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Journal of Arid Land 2015年第2期7卷 166-176页

作者： song hao SHANG State Key Laboratory of Hydroscience and Engineering Tsinghua University Department of Hydraulic Engineering Tsinghua University

Assessment of ecological flow or water level for water bodies is important for the protection of de- graded or degrading ecosystems caused by water shortage in arid regions, and it has become a key issue in water resources planning. In the past several decades, many methods have been proposed to assess ecological flow for rivers and ecological water level for lakes or wetlands. To balance water uses by human and ecosystems, we proposed a general multi-objective programming model to determine minimum ecological flow or water level for inland water bodies, where two objectives are water index for human and habitat index for ecosystems, respectively Using the weighted sum method for multi-objective optimization, minimum ecological flow or water level can be determined from the breakpoint in the water index-habitat index curve, which is similar to the slope method to de- termine minimum ecological flow from wetted perimeter-discharge curve. However, the general multi-objective programming model is superior to the slope method in its physical meaning and calculation method. This model provides a general analysis method for ecological water uses of different inland water bodies, and can be used to define minimum ecological flow or water level by choosing appropriate water and habitat indices. Several com- monly used flow or water level assessment methods were found to be special cases of the general model, including the wetted perimeter method and the multi-objective physical habitat simulation method for ecological river flow, the inundated forest width method for regeneration flow of floodplain forest and the lake surface area method for eco- logical lake level. These methods were applied to determine minimum ecological flow or water level for two repre- sentative rivers and a lake in northern Xinjiang of China, including minimum ecological flow for the Ertix River, minimum regeneration flow for floodplain forest along the midstream of Kaxgar River, and minimum ecologic

关键词： minimum ecological flow minimum ecological water level wetted perimeter method physical habitat simulation method inundated forest width method lake surface area method

Re-Os Dating of Chalcopyrite from the Lala IOCG Deposit in the Kangdian Copper Belt,China

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Acta Geologica Sinica(English Edition) 2015年第2期89卷 689-690页

作者： song hao song Shiwei Chengdu University of Technology Institute of Mineral Resources Chinese Academy of Geological Sciences

This study focused on the typical Precambrian copper- iron-gold-uranium deposits in the southwestern margin of the Yangtze block, such as the Lala in Huili, Dahongshan in Xinping, Yinachang in Wuding, and Chahe in Yuanjiang. Through systematically sampling of rocks, mineral and single mineral samples, this study discussed the continental geodynamics, age of magmatic rocks and metallogenic epoch, coupling relationship between polymetallic elements and ore-forming fluid, and the coupling relationship between magma evolution and polymetallic mineralization based on the latest metallogenic theory and modern analytical techniques.

关键词： Re-Os Dating of Chalcopyrite from the Lala IOCG Deposit in the Kangdian Copper Belt,China Os

Construction of Fe/Ag galvanic couple by mechanochemical in-situ reduced Ag to accelerate the degradation of Fe-based implant

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Science China(Technological Sciences) 2023年第10期66卷 2824-2836页

作者： YANG WenJing song hao Zhao ZhengYu SHUAI CiJun PAN hao Institute of Bioadditive Manufacturing Jiangxi University of Science and TechnologyNanchang 330013China Shenzhen Institute of Information Technology School of Sino-German RoboticsShenzhen 518172China State Key Laboratory of Precision Manufacturing for Extreme Service Performance College of Mechanical and Electrical EngineeringCentral South UniversityChangsha 410083China Department of Periodontics&Oral Mucosal Section Xiangya Stomatological HospitalCentral South UniversityChangsha 410013China

Orthopedic applications of Fe have been hindered by the insufficient degradation *** with noble elements(such as Ag,Au,and Pt)to generate galvanic couples is a feasible ***,the direct preparation of homogenous alloys by mechanical alloying or metallurgy is difficult because of the differences in strength,density,and *** this study,Ag_(2)O was selected as the precursor phase for incorporation into Fe to achieve a homogeneous distribution of Ag,which was then reduced in situ to Ag via a mechanochemical reduction reaction during mechanical *** composite powders were printed as implants by selective laser melting,where a fast cooling rate contributed to the retention of the phase distribution of the obtained *** electrochemical tests showed that the Fe-Ag_(2)O implant had a high corrosion current density(21.88±0.12μA/cm^(2))and instantaneous corrosion rate(0.23±0.05 mm/year).Moreover,the implant exhibited a faster degradation rate(0.22 mm/year)than Fe(0.15 mm/year)and Fe-Ag(0.21 mm/year)after immersion for 28 *** acceleration mechanism of the implant could be attributed to the uniformly distributed Ag particles triggering many galvanic couples with the Fe grains,which was confirmed by the observation of the corrosion *** addition,the composite implants exhibited good biocompatibility and antibacterial properties.

关键词： biodegradable implant mechanochemical reduction uniform dispersion galvanic corrosion

Chiral corrections to the masses of the doubly heavy baryons

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Communications in Theoretical Physics 2022年第8期74卷 69-75页

作者： hao-Ze Tong hao-song Li School of Physics Northwest UniversityXian 710127China Institute of Modern Physics Northwest UniversityXian 710127China Shaanxi Key Laboratory for theoretical Physics Frontiers Xian 710127China Peng Huanwu Center for Fundamental Theory Xian 710127China

We study the masses of the doubly bottom baryons and the charmed-bottom baryons up to O(p^(3))in heavy baryon chiral perturbation *** determine the unknown low energy constants in the quark model and lattice *** show ... 详细信息

关键词： doubly heavy baryon heavy baryon chiral perturbation theory mass

A Physicoempirical Model for Soil Water Simulation in Crop Root Zone

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Pedosphere 2011年第4期21卷 512-521页

作者： SHANG song-hao MAO Xiao-Min State Key Laboratory of Hydroscience and Engineering Department of Hydraulic Engineering Tsinghua University Beijing 100084 (China) Center for Agricultural Water Research in China College of Water Conservancy and Civil Engineering China Agricultural University Beijing 100083 (China)

To predict soil water variation in the crop root zone, a general exponential recession （GER） model was developed to depict the recession process of soil water storage. Incorporating the GER model into the mass balance model for soil water, a GER-based physicoempirical （PE-GER） model was proposed for simulating soil water variation in the crop root zone. The PE-GER model was calibrated and validated with experimental data of winter wheat in North China. Simulation results agreed well with the field experiment results, as well as were consistent with the simulation results from a more thoroughly developed soil water balance model which required more detailed parameters and inputs. Compared with a previously developed simple exponential recession （SER） based physicoempirical （PF^SER） model, PE-GER was more suitable f0r application in a broad range of soil texture, from light soil to heavy soil. Practical application of PE-GER showed that PE-GER could provide a convenient way to simulate and predict the variation of soil water storage in the crop root zone, especially in case of insufficient data for conceptual or hydrodynamic models.

关键词： general exponential recession model irrigation scheduling recession process soil texture

Assessment of impact of water diversion projects on ecological water uses in arid region

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Water Science and Engineering 2013年第2期6卷 119-130页

作者： song-hao SHANG Hui-jie WANG State Key Laboratory of Hydroscience and Engineering Tsinghua University Yellow River Engineering Consulting Co. Ltd.

In arid regions, large-scale water diversion from rivers leads to significant changes in river flow regimes, which may have large impacts on ecological water uses of river-dependent ecosystems, such as river, lake, wetland, and riparian ecosystems. To assess the integrated impact of water diversion on ecological water uses, we proposed a hierarchy evaluation model composed of four layers representing the evaluation goal, sub-areas of the influenced region, evaluation criteria, and water diversion schemes, respectively. The evaluation criteria for different types of ecological water uses were proposed, and the analytical hierarchy process was used for the integrated assessment. For a river ecosystem, the percentage of mean annual flow was used to define the grade of environmental flow. For a lake ecosystem, water recharge to the lake to compensate the lake water losses was used to assess the ecological water use of a lake. The flooding level of the wetland and the groundwater level in the riparian plain were used to assess the wetland and riparian ecological water uses, respectively. The proposed model was applied to a basin in northern Xinjiang in northwest China, where both water diversion and inter-basin water transfer projects were planned to be carried out. Based on assessment results for the whole study area and two sub-areas, an appropriate scheme was recommended from four planning schemes. With the recommended scheme, ecological water uses of the influenced ecosystems can be maintained at an acceptable level. Meanwhile, economical water requirements can be met to a great extent.

关键词： arid region water diversion project environmental impact assessment ecological water use environmental flow riparian forest analytic hierarchy process

TIDAL EFFECTS ON GROUNDWATER DYNAMICS IN COASTAL AQUI-FER UNDER DIFFERENT BEACH SLOPES

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Journal of Hydrodynamics 2012年第1期24卷 97-106页

作者： LIU Yi SHANG song-hao MAO Xiao-min College of Water Conservancy and Civil EngineeringChina Agricultural UniversityBeijing 100083China State Key Laboratory of Hydroscicncc and Engineering Department of Hydraulic EngineeringTsinghuaUniversityBeijing 100084China College of Water Conservancy and Civil Engineering China Agricultural UniversityBeijing 100083China

The tide induced groundwater fluctuation and the seawater intrusion have important effects on hydrogeology and ecology of coastal *** previous studies,there were few quantitative evaluations of the joint effects of the beach slope and the tide fluctuation on the groundwater *** this article,a numerical model is built by using the software FEFLOW with consideration of seawater intrusion,tide effects,density dependent flow and beach sloping *** simulation results are validated by laboratory experimental data in *** numerical scenarios are designed in a practical scale with different beach *** show that the groundwater fluctuation decays exponentially with the distance to the beach,i.e.,,and our simulation further shows that the beach slope influence can be expressed in the form of a logarithm *** for the same location,the amplitude increases logarithmically with the beach angle in the form,where and are related with the horizontal distance（）in the form of a logarithm *** beach slope has no influence on the phase lag,although the latter increases regularly with the distance from the *** beach slope effect on the seawater intrusion is investigated through the quantitative relationship among the relative intrusion length（）,the relative enhancement of the tide induced seawater intrusion（）and the beach angle（）.It is shown that the tide effects on a milder beach is much greater than on a vertical one,and both λ and κ can be expressed in logarithm functions *** tidal effect on the flow field in the transition zone for a particular mild beach is also studied,with results showing that the tide induced fluctuation of is similar to the groundwater table fluctuation while shows a distinct variation along both directions.

关键词： tidal effects salt wedges saline intrusion beach slope finite element method

Experimental study on correlation between sound velocity and solute molecular weight in polyethylene glycol solution

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Science China(Physics,Mechanics & Astronomy) 2009年第1期52卷 82-86页

作者： YIN XiangYu song hao ZHOU HuiJun Department of Materials Science and Engineering Nanjing UniversityNanjing 210093China Department of Physics Nanjing UniversityNanjing 210093China

In this study,ultrasound grating was used to measure the sound velocity in solutions of ethylene glycol and polyethylene glycol with molecular weights of 200,600,2000,and *** found Parthasarathy empirical rule,that is,sound velocity is higher in the solution of larger molecules,is invalid in the case of polyethylene glycol solution. We tried to provide a tentative explanation using the Flory-Krigbaum's chained block cloud model.

关键词： ultrasound grating velocity of sound polyethylene glycol

Magnetic moments of hidden-charm strange pentaquark states

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Chinese Physics C 2022年第12期46卷 194-207页

作者： Feng Gao hao-song Li School of Physics Northwest UniversityXi'an 710127China Institute of Modern Physics Northwest UniversityXi'an 710127China Shaanxi Key Laboratory for theoretical Physics Frontiers Xi'an 710127China Peng Huanwu Center for Fundamental Theory Xi'an 710127China

In this study,the magnetic moments of hidden-charm strange pentaquark states with quantum numbers J^(P)=1^(±)/2,3^(±)/2,5^(±)/2,and 7^(+)/2 are calculated in the molecular,diquark-diquark-antiquark,and diquark-triquark *** numerical results demonstrate that the magnetic moments change for different spin-orbit couplings within the same model and when involving different models with the same angular momentum.

关键词： magnetic moment pentaquark molecular model diquark triquark