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The Mid-route of South-to-North Water Transfer Project mainly uses open channels for water transportation, with long distances and large spans along the route, and significant differences in climate between the ends of the channels. Low temperature can cause ice to appear in the channel, posing great challenges to the operation and scheduling of the channel. The bottom layer warm water of the Xiong an res- ervoir near the Xiheishan check gate is diverted into the channel to increase the channel water temperature, bringing new ideas for regulating the channel ice condition. This article establishes a one-dimensional channel ice hydraulic simulation model considering the inflow of warm water from the side, and conducts simulation research on the changes in water temperature and ice conditions inside the channel after warm water flow into the channel. The channel model was constructed based on the main canal of the Beijing-Shijiazhuang section as the prototype. By setting different inflow ratios, inflow temperatures, mixed discharges, and inflow times, the variation patterns of water temperature and ice cover thickness along the channel under different inflow conditions were explored. The results indicate that: (T) the idea of using offline reservoir charging to alleviate channel ice conditions is basically feasible, but the impact of the inflow from the regulating reservoir on the water temperature of the main channel is mainly within the downstream 20km channel. The closer the channel is to the downstream, the less affected it is, and the longer the delay time of water temperature rise. (2) The higher the proportion of incoming water from the reservoir, the more significant the impact on the water temperature of the canal. (3) The higher the temperature of the inflow water from the reservoir, the more significant the effect of improving the water temperature of the downstream channel pool, and the duration of the ice cover is significantly shortened, but the range of ice formation is not significantly reduced. (4) The larger the mixed discharge, the slower the water temperature decreases, and the closer the section with ice is to the downstream. (5) In actual scheduling, it is necessary to combine meteorological forecasts and start adding warm water to the channel before the winter cools down, and continue throughout the entire low-temperature period to achieve the best ice relief effect. The research results of this article can provide data support for the determination of alleviating the ice condition by water inflow, serve as a reasonable reference for the feasibility of engineering, and also provide reference for the calculation and simulation of other similar temperature mixing problems. [ABSTRACT FROM AUTHOR]

Objective: To study the chemical constituents of the aerial parts of Gladiolus gandavensis., Methods: These compounds were isolated by silica gel, Sephades LH-20 and RP-18 column chromatographies. And their structures were elucidated by spectroscopic methods., Results: Ten compounds were isolated, and their structures were identified as kaempferol (I), apigenin-7-O-alpha-L-rhamnoside(II), tamarixetin-3-robinobioside(III), nicotiflorin(IV), astragalin-2"-O-beta-D-glucopyranoside(V), quercetin-3-O-(6"-O-Ecaffeoyl)-beta-D-glucopyranoside(VI), beta-sitosterol(VII), daucosterol(VII), isopentylgentiobioside(IX), glycerol-alpha-monohexacosanate(X)., Conclusion: Except for compounds VII and VIII, others compounds are obtained from this plant for the first time.