Abstract: The present disclosure provides a risk assessment method of water inrush in tunnels constructed in water-rich grounds. The method includes the following steps: simulating a tunnel excavation process by finite element software MIDAS GTS NX and fluid-structure interaction; according to a research method of control variables, analyzing effects of a groundwater level, an elastic modulus and advanced pipe shed grouting on the stability of surrounding rock, and improving an algorithm of a radial basis function (RBF) neural network using a Grey Relation Analysis (GRA)-based Partitioning Around Medoid (PAM) clustering algorithm to assess risks of water inrush occurring in Qingdao area.

Abstract: The present disclosure provides a multi-factor quantitative analysis method for deformation of a neighborhood tunnel. The method includes the following steps: analyzing monitoring data generated at a tunnel site; simulating collapse occurring at a shallow buried section of a tunnel; determining the degree of influence of each factor on the tunnel and a stratum; and determining quantitative influence of each factor on tunnel deformation. The present disclosure can not only provide an accurate theoretical basis for the construction of the shallow buried section of the small-distance tunnel, but also guarantee safety and cost saving during tunnel construction.

Abstract: The present disclosure provides an ecological governance method based on erosion prevention and control for a gentle slope farmland and relates to the technical field of ecological governance of farmlands. The ecological governance method based on erosion prevention and control for a gentle slope farmland includes the following steps: sampling a gentle slope farmland to investigate erosion thereof; and determining erosion of a gentle slope cultivated land and selecting a corresponding recovery strategy based on a detection result of a sample, a soil quality index (SQI), and a comprehensive vegetation quality index (VQI), where the recovery strategy includes a natural recovery method and a biological-farming comprehensive recovery method; enclosing the gentle slope cultivated land, fallowing the gentle slope cultivated land and reducing tillage; exterminating insect pests and poisonous weeds in the enclosed area; and turning over straws under soil by a cultivator. The growth of poisonous weeds is inhibited.

Abstract: Tetraphosphorous ligands are combined with transition metal salts to form catalysts for use in hydroformylation, isomerization-hydroformylation, hydrocarboxylation, hydrocyan-ation, isomerization-formylation, hydroaminomethylation and similar related reactions.

Abstract: Tetraphosphorous ligands are combined with transition metal salts to form catalysts for use in hydroformylation, isomerization-hydroformylation, hydrocarboxylation, hydrocyan-ation, isomerization-formylation, hydroaminomethylation and similar related reactions.

Abstract: Tetraphosphorous ligands are combined with transition metal salts to form catalysts for use in hydroformylation, isomerization-hydroformylation, hydrocarboxylation, hydrocyan-ation, isomerization-formylation, hydroaminomethylation and similar related reactions.

Abstract: Tetraphosphorous ligands are combined with transition metal salts to form catalysts for use in hydroformylation, isomerization-hydroformylation, hydrocarboxylation, hydrocyan-ation, isomerization-formylation, hydroaminomethylation and similar related reactions.