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| 1 | Singularity theories and methods for characterizing mineralization processes and mapping geo-anomalies for mineral deposit prediction显示文摘在这份报纸,我们证明 geo 异例能根据理论开发了描绘非线性的矿化作用过程的奇特为矿物沉积物预言被描出。联系奇特和 geo 异例与现代非线性的理论和方法使它可能到份量上学习 geo 异例。这份报纸为为矿物沉积物预言描绘并且印射 geo 异例介绍非线性的矿化作用过程和非线性的方法的最新发达的奇特分析。作为 geo 异例引起的单个矿化作用过程的产品,矿藏能借助于分数维图形或 multifractal 模型被描绘。奇特能描绘 geo 反常的度,这被显示出,并且这被表明了为印射未被发现的矿藏的异例有用。从一个非线性的过程观点的矿化作用和矿藏的学习是一个新却有希望的研究方向。这研究强调在 geo 异例和奇特之间的关系,包括导致奇特和 geo 异例的单个过程,奇特和 geo 异例和为矿物沉积物预言的 geo 异例的鉴定的描述。这些概念和方法在云南在 Gejiu 矿物质区域用 Sn 矿物沉积物预言的案例研究被表明,中国。 | Qiuming Cheng Pengda Zhao | 2011 | Geoscience Frontiers2011，2，1： | 9 |
| 2 | Effects of sediment physical properties on the phosphorus release in aquatic environment显示文摘Particle size, porosity, and the initial phosphorus concentration in sediments are the main factors affecting phosphorus release flux through the sediment-water interface. Sediments can be physically divided to muddy and sandy matters, and the adsorption-desorption capacity of sediment with phosphorus depends on particle size. According to phosphorus adsorption-desorption experiments, phosphorus sorption capacity of the sediment decreases with the increase of particle dimension. But among the size-similar particles, sediment with a bigger particle size has the larger initial phosphorus release rate. In terms of muddy and sandy sediments, there are inversely proportional relationships between the release rate and the flux. Due to the contact of surface sediment and the overlying water, the release flux from the sediment is either from direct desorption of surface sediment layer or from the diffusion of pore water in the sediment layer, which is mainly determined by sediment particle size and porosity. Generally, static phosphorus release process may include two stages: the first is the initial release. As for coarse particles, phosphorus is desorbed from surface sediment. And for fine particles, phosphorus concentration in water often decreases, mainly from pore water by the molecular diffusion. During the second stage, pore water flows faster in coarse sediment, and phosphorus is easy to desorb from the surface of the particles as diffusion dominates. For the smaller liquid-solid ratio of fine particles and the larger amount of phosphorus adsorption, the release flux from pore water due to diffusion is very small with longer sorption duration. | ZHU HongWei WANG DaoZeng CHENG PengDa FAN JingYu ZHONG BaoChang | 2015 | Science China(Physics,Mechanics & Astronomy)2015，58，2： | 8 |
| 3 | The mechanisms of contaminants release due to incipient motion at sediment-water interface显示文摘Sediments in many rivers and lakes are subjected to resuspension due to a combination of hydrodynamics.However,the roles of contaminant-contained dissolved and particulate sediments during the resuspension release are rarely studied.This study focuses on the release quantity of contaminants in both water phase and solid phase.Conservative tracer(NaCl)and reactive tracer(Phosphorus)were respectively added to cohesive fine-grained sediments and non-cohesive coarse-grained sediments.A range of typical shear stress was conducted to characterize the time-depended release of contaminants in a laboratory flume.When the sediment started to move,the concentration of contaminant in the overlying water increased with the bed shear stress,but the dissolved contaminants responded faster than the particulate ones.The observed contaminant release process can be divided into three main stages:the initial two hours fast mixing:the release contribution of pore water could reach up to 75%;the middle 4–6 h adsorption:the partitioning coefficient of contaminant between water phase and solid phase decreased over the time,and the adsorption of contaminates from resuspended sediment dominated the negative release;the last equilibrium stage:the desorption and adsorption reached equilibrium,and the reactive contaminant made an impact on the water quality in the solid phase.The existing formulas to evaluate the release flux are far from practice meaning as the sediment contaminants undergo a very complex release process. | ZHU HongWei CHENG PengDa ZHONG BaoChang WANG DaoZeng | 2014 | Science China(Physics,Mechanics & Astronomy)2014，57，8： | 4 |
| 4 | Numerical simulation of phosphorus release from resuspended sediment显示文摘One of the main issues in environmental hydraulics is pollutant release from sediments.For instance,the strong affinity between phosphorus and sediment permits most of the phosphorus to be adsorbed on the surface of the sediment particles in rivers or lakes.Post sediment resuspension,phosphorus is desorbed from the sediment to the overlying water.The release of phosphorus from the resuspended sediment is an important process in the secondary pollution of water.Herein,a coupled mechanical model of the overlying water,sediment,and pollutant was established based on the experimentally gathered data.Two types of sediment with different adsorption and desorption characteristics were selected to simulate the process of sediment resuspension and phosphorus release under different hydrodynamic conditions.The simulation results were subsequently used to analyze the relationship between the flow field characteristics and phosphorus concentration,from which the relationships between velocity,particle volume fraction,turbulent kinetic energy,total phosphorus concentration,desorbed phosphorus concentration,and time were elucidated.Based on the results,phosphorus is rapidly released into the overlying water from the resuspended sediment,and it reaches a peak value in a short duration.Unlike the release process of non-adsorption pollutants,hydrodynamic conditions and sediment properties play a crucial role in the phosphorus release process.The turbulent kinetic energy rapidly increases with the flow velocity,whereas the desorbed phosphorus concentration exhibits a certain relationship with the particle volume fraction and turbulent kinetic energy.In particular,the turbulent kinetic energy increases the desorbed phosphorus concentration per unit time.Additionally,the time taken by the total phosphorus concentration to attain its peak value is closely related to the characteristics of the flow field,whereas the amount of phosphorus is closely related to sediment properties.Post sediment resuspension,the release of phosphorus shows the characteristics of a centralized and massive release,which suggests that the total phosphorus concentration in the overlying water would change in a short duration and cause secondary pollution in the water environment. | Pengda Cheng Xinquan Wang Chun Feng | 2020 | Acta Mechanica Sinica2020，36，6： | 3 |
| 5 | Transport mechanisms of contaminants released from fine sediment in rivers显示文摘Contaminants released from sediment into rivers are one of the main problems to study in environmental hydrodynamics. For contaminants released into the overlying water under different hydrodynamic conditions, the mechanical mechanisms involved can be roughly divided into convective diffusion, molecular diffusion, and adsorption/desorption. Because of the obvious environmental influence of fine sediment( D90 = 0.06 mm), non-cohesive fine sediment, and cohesive fine sediment are researched in this paper, and phosphorus is chosen for a typical adsorption of a contaminant. Through theoretical analysis of the contaminant release process, according to different hydraulic conditions, the contaminant release coupling mathematical model can be established by the N–S equation, the Darcy equation,the solute transport equation, and the adsorption/desorption equation. Then, the experiments are completed in an open water flume. The simulation results and experimental results show that convective diffusion dominates the contaminant release both in non-cohesive and cohesive fine sediment after their suspension, and that they contribute more than 90 % of the total release. Molecular diffusion and desorption have more of a contribution for contaminant release from unsuspended sediment. In unsuspension sediment, convective diffusion is about 10–50 times larger than molecular diffusion during the initial stages under high velocity; it is close to molecular diffusion in the later stages. Convective diffusion is about 6 times larger than molecular diffusion during theinitial stages under low velocity, it is about a quarter of molecular diffusion in later stages, and has a similar level with desorption/adsorption. In unsuspended sediment, a seepage boundary layer exists below the water–sediment interface,and various release mechanisms in that layer mostly dominate the contaminant release process. In non-cohesive fine sediment, the depth of that layer increases linearly with shear stress. In cohesive fine sediment, the range seepage boundary is different from that in non-cohesive sediment, and that phenomenon is more obvious under a lower shear stress. | Pengda Cheng Hongwei Zhu Baochang Zhong Daozeng Wang | 2015 | Acta Mechanica Sinica2015，31，6： | 3 |
| 6 | 4-methylumbelliferone (4-MU) enhances drought tolerance of apple by regulating rhizosphere microbial diversity and root architecture显示文摘The dwarfing rootstocks-mediated high-density apple orchard is becoming the main practice management.Currently,dwarfing rootstocks are widely used worldwide,but their shallow root system and drought sensitivity necessitate high irrigation requirements.Here,the root transcriptome and metabolome of dwarfing(M9-T337,a drought-sensitive rootstock)and vigorous rootstocks(Malus sieversii,a drought-tolerant species,is commonly used as a rootstock)showed that a coumarin derivative,4-Methylumbelliferon(4-MU),was found to accumulate significantly in the roots of vigorous rootstock under drought condition.When exogenous 4-MU was applied to the roots of dwarfing rootstock under drought treatment,the plants displayed increased root biomass,higher root-to-shoot ratio,greater photosynthesis,and elevated water use efficiency.In addition,diversity and structure analysis of the rhizosphere soil microbial community demonstrated that 4-MU treatment increased the relative abundance of putatively beneficial bacteria and fungi.Of these,Pseudomonas,Bacillus,Streptomyces,and Chryseolinea bacterial strains and Acremonium,Trichoderma,and Phoma fungal strains known for root growth,or systemic resistance against drought stress,were significantly accumulated in the roots of dwarfing rootstock after 4-MU treatment under drought stress condition.Taken together,we identified a promising compound—4-MU,as a useful tool,to strengthen the drought tolerance of apple dwarfing rootstock. | Dehui Zhang Jieqiang He Pengda Cheng Yutian Zhang Abid Khan Shicong Wang Zhongxing Li Shuang Zhao Xiangqiang Zhan Fengwang Ma Xuewei Li Qingmei Guan | 2023 | Horticulture Research2023，10，7： | 0 |
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