CaO needs to show high activity to be used as Ca-sorbent and slagging agent. Hydration activity is an important characteristic to evaluate the activity of CaO. In this study, carbide slag from polyvinyl chloride(PVC) ...CaO needs to show high activity to be used as Ca-sorbent and slagging agent. Hydration activity is an important characteristic to evaluate the activity of CaO. In this study, carbide slag from polyvinyl chloride(PVC) industry was utilized as precursor for preparing high activity CaO. The roles of crystallite grain, average pore diameter(APD) and volume fraction of pore b 200 nm in diameter(VF200) in hydration activity of CaO from carbide slag(CS-CaO)were respectively investigated. The hydrolysis kinetics model of CaO shows a three-dimensional spherically symmetric diffusion model(D4), which suggests that hydration activity was mainly associated with APD and VF200 of CS-CaO with limited correlation to the crystal size. Specifically, the hydration activity of CS-CaO is increased with increasing VF200, while decreased with increasing APD. Under the invariable calcination temperature,the core–shell structure formed by the addition of graphite or Ca CO3 to CS effectively inhibits the sintering of CS-CaO and improves VF200. Consequently, the hydration activity of CS-CaO increased from 22.79 ℃·min^-1 to27.19 ℃·min^-1 and to 29.27 ℃·min^-1, with addition of 5% graphite or 5% CaCO3 into carbide slag, respectively.展开更多
The results make it clear that there are total 11 families, 29 genera and 43 species of spiders in the rice field of Dong Fang Hong Farm. Among them, there are 8 families, 19 genera and 28 species in the early rice fi...The results make it clear that there are total 11 families, 29 genera and 43 species of spiders in the rice field of Dong Fang Hong Farm. Among them, there are 8 families, 19 genera and 28 species in the early rice field, and 10 families, 27 genera and 36 species in the late rice field. The spatial distribution pattern of mixed spider populations in rice fields was different during different development stages of rice plant. During the prophase, metaphase and anaphase of early rice plant development, the spatial distribution pattern of mixed spider populations was aggregative, random and aggregative respectively. During the prophase, metaphase and anaphase of late rice plant development, the spatial distribution pattern was uniform, aggregative and uniform respectively.展开更多
基金Supported by the National Natural Science Foundation of China(U1610101,51422405).
文摘CaO needs to show high activity to be used as Ca-sorbent and slagging agent. Hydration activity is an important characteristic to evaluate the activity of CaO. In this study, carbide slag from polyvinyl chloride(PVC) industry was utilized as precursor for preparing high activity CaO. The roles of crystallite grain, average pore diameter(APD) and volume fraction of pore b 200 nm in diameter(VF200) in hydration activity of CaO from carbide slag(CS-CaO)were respectively investigated. The hydrolysis kinetics model of CaO shows a three-dimensional spherically symmetric diffusion model(D4), which suggests that hydration activity was mainly associated with APD and VF200 of CS-CaO with limited correlation to the crystal size. Specifically, the hydration activity of CS-CaO is increased with increasing VF200, while decreased with increasing APD. Under the invariable calcination temperature,the core–shell structure formed by the addition of graphite or Ca CO3 to CS effectively inhibits the sintering of CS-CaO and improves VF200. Consequently, the hydration activity of CS-CaO increased from 22.79 ℃·min^-1 to27.19 ℃·min^-1 and to 29.27 ℃·min^-1, with addition of 5% graphite or 5% CaCO3 into carbide slag, respectively.
文摘The results make it clear that there are total 11 families, 29 genera and 43 species of spiders in the rice field of Dong Fang Hong Farm. Among them, there are 8 families, 19 genera and 28 species in the early rice field, and 10 families, 27 genera and 36 species in the late rice field. The spatial distribution pattern of mixed spider populations in rice fields was different during different development stages of rice plant. During the prophase, metaphase and anaphase of early rice plant development, the spatial distribution pattern of mixed spider populations was aggregative, random and aggregative respectively. During the prophase, metaphase and anaphase of late rice plant development, the spatial distribution pattern was uniform, aggregative and uniform respectively.
