This paper is based on the ABAQUS finite element simulation software to study the seismic performance of the glass fiber reinforced polymer (GFRP) beam-column joint connected by the slotted-hole angle steel. Non-linear finite element analysis for the effect of slotted-hole on GFRP beams and different slotted-hole sizes on the seismic performance of joints were conducted. Four specimens D1, D2, D3 and D4 with different slotted-hole lengths were designed. The moment-rotation hysteretic curve, skeleton curve and energy dissipation curve of the specimen are obtained. The finite element analysis results show that: 1) the energy consumption of the slotted-hole joint is about 4%-21% higher than that of the ordinary circular hole joint. 2) The longer the slotted holes length is, the better the seismic energy dissipation performance is. The energy dissipation capacity increases by 3%-12% for each 2 mm increase in the slotted-hole length. 3) Although the larger the slotted-hole length is, the better the energy consumption is, the larger the deformation of the component will be caused. Therefore, according to the requirements of serviceability limit state, it is suggested that the slotted-hole length should be between 2 mm and 4 mm.

Selenium doped carbon quantum dots (Se-CQDs) are synthesized by a facile hydrothermal process. The Se-CQDs show narrow size distribution in the range of 3-4 nm, good optical properties, and high sensitivity in detection of various reactive oxygen species (ROS) as revealed by several characterizations. The Se-CQDs are then modified by three kinds of organelle targeting molecules with the aim of targeting detection of ROS in specific organelles. The confocal fluorescence studies on modified Se-CQDs and commercial organelle marker demonstrate the successful targeting detection of ROS in different organelles by our specific modified Se-CQDs.

In China, the distribution of water resources is uneven in time and space. The effective allocation of water resources can realize the rational utilization of water resources. Reservoirs are an important part of the basin system, and the rational operation of reservoirs can realize the optimal allocation of water resources. Flood forecast is of great significance for reservoir operation. In order to realize the optimal operation of Dashimen reservoir in Xinjiang, aiming at the flood forecast in the dry area affected by melting snow, this paper expanded and improved the traditional hydrological forecast model, built the flood forecast model in the dry area with the coupling snowmelt based on the northern Shaanxi model and Elman neural network, and using the typical rainfall and runoff data in this area The results show that the relative error of the model is less than 10% and the accuracy is high, which can be used in the actual forecast. This model realizes the flood forecast in the drought area affected by snowmelt, and provides a new idea for the flood forecast of reservoir in the drought area affected by snowmelt, which has a certain guiding significance for the flood forecast in the drought area.

The dry anaerobic digestion performances were investigated at the temperature of 35±1°Cwith addition of propionic acid at different concentrations in five lab-scale reactors (R1-R5) to investigate the effect of propionic acid accumulation on methane production in dry mesophilic anaerobic digestion. And the volatile fatty acids, biogas and microbial community were detected. The active of microbial community and the methane generation would be inhibited when the propionic acid exceeded 30 gL 1 , which affected not only syntrophic propionate-oxidizing bacteria but also acetate-utilizing methanogens. Eubacteria decreased sharply accompany with the higher concentration of propionic in R4 and R5. The relative abundance of acetoclastic methanogens was directly correlated with volatile solids removals and methane generation in dry anaerobic reactors. Otherwise, the quantity of syntrophic propionate-oxidizing bacteria was positively linear correlated with propionic acid when the concentration was below 30 gL 1 . The methanogenic bacteria activity in R3 was the best with the methane yield of 27.01 mLCH 4 g -1 VS d -1 . The results suggested that appropriate propionate could enhance methane production in the dry anaerobic fermentation.

The smooth surface and the lack of active groups make para-aramid fiber reinforced composites have poor interfacial adhesion property, which limits their applications in various fields. In this study, aramid fiber was coated with nano-coating solution and functional groups such as epoxy and amino groups were introduced to the surface of aramid fiber to enhance the surface activity of the fiber, thereby improving the adhesion between fiber and resin. The surface composition and roughness of the modified fibers were characterized by Fouier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and scanning electron microscope (SEM), respectively. The effect of functional groups on the interfacial adhesion properties of aramid/epoxy composites was studied by the interfacial shear strength (IFSS) and the flexural strength. aramid fiberter modification, the roughness and the polarity of the fiber were considerably improved. The IFSS reached 45.9 MPa with a significant enhancement by 27.5%; while the flexural strength increased from 240.7 MPa to 302.2 MPa, with a reinforcement of 25.6%, indicating that the study provides an effective method to achieve highiy active aramid fiber.

Supercritical CO 2 (ScCO 2 ) invades oilwell cement and forms carbonate layers in the cement under geological CO 2 sequestration conditions. Long-term invasion of ScCO 2 makes the carbonation structure unstable and prone to damage. Nanoclay was modified with ScCO 2 as the solvent and intercalator for the reinforcement of oilwell cement, forming the microcrystalline Nanoclay (MC Nanoclay). MC Nanoclay is identified and added into the cement slurry to reinforce oilwell cement after the above modification. Microcrystal calcite is found in the MC Nanoclay with transmission electron microscopy (TEM) and selected area electron diffraction (SAED) analyses. Both mechanical properties and microstructural evolution of MC Nanoclay reinforced oilwell cement are investigated, showing that the carbonation was inhibited with MC Nanoclay. With generalized analysis from microcrystal formation and densified carbonation area, the reinforce mechanisms of MC Nanoclay were revealed in this study.