Effect of treatment process on consolidation efficiency of fugitive dust cemented by bio-activated cementitious material based on CO2 capture

As a new green and environmental material, bio-activated cementitious material is attracting extensive attention. This study confirmed that the bio-activated cementitious material could mineralize and cement fugitive dust into the cal- cite-consolidation-layer based on CO2 capture and utilization. The results illustrated that treatment processes （non-pressure spraying, pressure spraying, non-pressure blending and pressure blending） had a strong effect on the microstructure and prop- erties of calcite-consolidation-layer. According to the analysis of X-ray diffraction （XRD） and Fourier transform infrared （FTIR）, calcite was prepared by bio-activated cementitious material during the cementation process. Meanwhile, scanning electron microscopy （SEM） and thermogravimetric-differenfial scanning calorimetry （TG-DSC） were adopted to measure the corresponding variation of porous characteristics and calcite content caused by different treatment processes. The results indi- cated that the microstructure of calcite-consolidation-layer from the spraying process had lower porosity and higher content of calcite than from blending processes. In addition, the mechanical properties of calcite-consolidation-layer were also tested. The hardness and compressive strength, which reached 19.5 GPa and 0.6 MPa, respectively, of calcite-consolidation-layer from the pressure spraying process were higher than those from the other three treatment processes. Compared with the non-treatment process, the four treatment processes had superior wind erosion resistance. Under the wind speed of 12 m/s, the mass loss of calcite-consolidation-layer from the pressure spraying process decreased from 2150.2 to 23.8 g/（m^2 h）.

Physiological potential of soybean seeds treated with thiamethoxam and submitted to storage

Bio-activators such as thiamethoxam have been used to increase the productive potential of plants, by means of metabolic and plant morphology modifications. Nevertheless, very little is known regarding the effectiveness of this insecticide when incorporated into lower quality level soybean seeds, particularly during storage. The objective of this work was to assess the influence of thiamethoxam on the physiological potential of soybean seeds with different initial vigor levels during four storage periods. Three vigor levels of cultivar Anta—low (35%), medium (70%) and high (85%) vigor—of soybean seeds were utilized in this experiment. The experimental design was completely randomized in a 3 × 2 × 4 factorial scheme—3 levels of vigor (low, medium and high);2 seed treatments (with and without thiamethoxam) and 4 storage periods (0, 30, 60 and 90 days). The analyzed variables were: germination, first germination count, accelerated aging test, seedling length and emergence speed index. Thiamethoxam-treated soybean seeds benefit the physiological potential of both medium and high vigor seeds during storage up to 30 days. Whereas, the use of thiamethoxam was shown to be ineffective in improving the physiological quality of initial low vigor seeds.