The effects of different outer diameters and surface oxygen contents on the adsorption of heavy metals onto six types of multi-walled carbon nanotubes (MWCNTs) were investigated in an aqueous solution and lead was c...The effects of different outer diameters and surface oxygen contents on the adsorption of heavy metals onto six types of multi-walled carbon nanotubes (MWCNTs) were investigated in an aqueous solution and lead was chosen as a model metal ion. The results indicated that the percentage removal and adsorption capacity of lead remarkably increased with decreasing outer diameter due to larger specific surface area (SSA). The SSA-normalized maximum adsorption capacity (qJSSA) and SSA-normalized adsorption coefficient (KdSSA) were strongly positively correlated with surface oxygen content, implying that lead adsorption onto MWCNTs significantly increases with the rise of oxygen content and decreases with decreasing SSA. The calculated thermodynamic parameters indicated that adsorption of lead on MWCNTs was endothermic and spontaneous. When the oxygen content of MWCNTs increased from 2.0% to 5.9%, the standard free energy (AGt) became more negative, which implied that the oxygenated functional groups increased the adsorption affinity of MWCNTs for lead. Through calculation of enthalpy (△H0), AGO and free energy of adsorption (Ea), lead adsorption onto MWCNTs was recognized as a chemisorption process. The chemical interaction between lead and the phenolic groups of MWCNTs could be one of the main adsorption mechanisms due to highly positive correlations between the phenolic groups and Kd/SSA or qm/SSA.展开更多
The Huize large-sized Pb-Zn deposit in Yunnan Province, China, is characterized by favorable metallogenic background and particular geological settings. This suggested that the ore-forming mechanism is relatively uniq...The Huize large-sized Pb-Zn deposit in Yunnan Province, China, is characterized by favorable metallogenic background and particular geological settings. This suggested that the ore-forming mechanism is relatively unique. On the basis of geological features such as the contents of mineralization elements, the REE concentrations of gangue calcites, the REE concentrations of calcite veins in the NE-trending tectonic zone and the Pb, Sr, C, H and O isotopic compositions of different minerals, this paper presents that the ore-forming materials and ore-forming fluids of the deposit were derived from various types of strata or rocks. This is a very significant conclusion for us to further discuss the mineralization mechanism of the deposit at depth and establish an available genetic model.展开更多
The mechanical properties of multi-lead rubber bearings (MLRBs) were investigated by experiment and finite element analysis. First, the vertical stiffness, horizontal stiffness and yielded shear force were tested fo...The mechanical properties of multi-lead rubber bearings (MLRBs) were investigated by experiment and finite element analysis. First, the vertical stiffness, horizontal stiffness and yielded shear force were tested for four MLRB specimens and two specimens of the single-lead rubber bearings ( SLRBs). Then, the MLRBs were modeled by the explicit finite element analysis software ANSYS/ LS-DYNA, in order to evaluate the horizontal force-displacement hysteretic curves under static vertical and dynamical horizontal loadings. The disagreement between the tested and theoretical values was less than 11.4%, and MLRBs and SLRBs were similar in vertical stiffness, pre-yield stiffness and yield stiffness.展开更多
Alzheimer disease(AD) has now become the most common brain disorder among the older population. In addition, the currently existing therapeutics only offer temporary symptomatic relieves. Therefore, further research a...Alzheimer disease(AD) has now become the most common brain disorder among the older population. In addition, the currently existing therapeutics only offer temporary symptomatic relieves. Therefore, further research and development of more efficacious and disease-modifying agents for the prevention, treatment and restoration of AD will have tremendous value from both scientific, and economic standpoints. Over the past few years, our series of studies have identified several highly promising anti-AD dimeric leads, with disease-modifying potentials. In this presentation, the latest progress on the neuroprotective and disease modifying effects and the underlying mechanisms of those candidates will be comprehensively illustrated and discussed.展开更多
基金supported by the National High Technology Research and Development Program (863) of China (No.2007AA06Z334)the Scholarship Award for Excellent Doctoral Student granted by Ministry of Education and the Shanghai Jiao Tong University Innovation Fund for Postgraduates+1 种基金the State Key Laboratory of Pollution Control and Resource Reuse Foundation (No. PCRRY11009)the Program for Young Excellent Talents at Tongji University (No. 2010KJ026)
文摘The effects of different outer diameters and surface oxygen contents on the adsorption of heavy metals onto six types of multi-walled carbon nanotubes (MWCNTs) were investigated in an aqueous solution and lead was chosen as a model metal ion. The results indicated that the percentage removal and adsorption capacity of lead remarkably increased with decreasing outer diameter due to larger specific surface area (SSA). The SSA-normalized maximum adsorption capacity (qJSSA) and SSA-normalized adsorption coefficient (KdSSA) were strongly positively correlated with surface oxygen content, implying that lead adsorption onto MWCNTs significantly increases with the rise of oxygen content and decreases with decreasing SSA. The calculated thermodynamic parameters indicated that adsorption of lead on MWCNTs was endothermic and spontaneous. When the oxygen content of MWCNTs increased from 2.0% to 5.9%, the standard free energy (AGt) became more negative, which implied that the oxygenated functional groups increased the adsorption affinity of MWCNTs for lead. Through calculation of enthalpy (△H0), AGO and free energy of adsorption (Ea), lead adsorption onto MWCNTs was recognized as a chemisorption process. The chemical interaction between lead and the phenolic groups of MWCNTs could be one of the main adsorption mechanisms due to highly positive correlations between the phenolic groups and Kd/SSA or qm/SSA.
文摘The Huize large-sized Pb-Zn deposit in Yunnan Province, China, is characterized by favorable metallogenic background and particular geological settings. This suggested that the ore-forming mechanism is relatively unique. On the basis of geological features such as the contents of mineralization elements, the REE concentrations of gangue calcites, the REE concentrations of calcite veins in the NE-trending tectonic zone and the Pb, Sr, C, H and O isotopic compositions of different minerals, this paper presents that the ore-forming materials and ore-forming fluids of the deposit were derived from various types of strata or rocks. This is a very significant conclusion for us to further discuss the mineralization mechanism of the deposit at depth and establish an available genetic model.
文摘The mechanical properties of multi-lead rubber bearings (MLRBs) were investigated by experiment and finite element analysis. First, the vertical stiffness, horizontal stiffness and yielded shear force were tested for four MLRB specimens and two specimens of the single-lead rubber bearings ( SLRBs). Then, the MLRBs were modeled by the explicit finite element analysis software ANSYS/ LS-DYNA, in order to evaluate the horizontal force-displacement hysteretic curves under static vertical and dynamical horizontal loadings. The disagreement between the tested and theoretical values was less than 11.4%, and MLRBs and SLRBs were similar in vertical stiffness, pre-yield stiffness and yield stiffness.
基金Poly U(G-YBGQ G-SB81+3 种基金 G-YZ95)the Research Grant Council of Hong Kong(15101014)ITSP-Guangdong-Hong Kong Technology Cooperation Funding Scheme(GHP/012/16GD)Shenzhen Basic Research Program(JCYJ20160331141459373)
文摘Alzheimer disease(AD) has now become the most common brain disorder among the older population. In addition, the currently existing therapeutics only offer temporary symptomatic relieves. Therefore, further research and development of more efficacious and disease-modifying agents for the prevention, treatment and restoration of AD will have tremendous value from both scientific, and economic standpoints. Over the past few years, our series of studies have identified several highly promising anti-AD dimeric leads, with disease-modifying potentials. In this presentation, the latest progress on the neuroprotective and disease modifying effects and the underlying mechanisms of those candidates will be comprehensively illustrated and discussed.