Urban highway runoff samples from seventeen rainfall events were collected in Shanghai in 2011. The concentrations of ten heavy metals and sixteen polycyclic aromatic hydrocarbons PAHs are analyzed. The results show t...Urban highway runoff samples from seventeen rainfall events were collected in Shanghai in 2011. The concentrations of ten heavy metals and sixteen polycyclic aromatic hydrocarbons PAHs are analyzed. The results show that the heavy metal concentrations range within 0.50 to 51.80 As 0 to 20.80 Se 13.67 to 445.80 Zn 0 to 44.20 Pb 0 to 15.80 Ni 39.58 to 264.20 Fe 0 to 253.00 Mn 0 to 8.20 Cr 0 to 124.20 Cu and 159.83 to 536.40 μg/L Al . Se Pb Mn and Al concentrations in most samples exceed their corresponding criterion continuous concentrations CCCs while Zn and Cu concentrations exceed their criterion maximum concentrations CMCs .The concentrations ofΣPAHs range within 37.25 to 114.57 ng/L and concentrations of PAHs are all below their corresponding CCCs.Cu Zn and ΣPAHs show the first flush phenomenon. Analysis results of the modified Nemerow index method NIM indicate that runoff from eight rainfall events may have very strong biological toxicity effects four have strong effects three have moderate effects and only two have insignificant effects.Therefore it is concluded that urban highway runoff is a significant pollution source to aquatic ecosystems and needs immediate purification.展开更多
As an emerging class of crystalline porous materials, covalent organic frameworks(COFs) have been widely used as catalysts or catalyst supports. Flexible regulation of the pores and easy introduction of functional a...As an emerging class of crystalline porous materials, covalent organic frameworks(COFs) have been widely used as catalysts or catalyst supports. Flexible regulation of the pores and easy introduction of functional active sites onto the skeleton of COFs make them promising platforms for many catalysis applications. However, only a single function is generally observed in these COFs. Herein, we synthesized a negatively charged ionic COF(I-COF) and successfully incorporated functionalized counter ions, that is, metallic Mn2+ and a coordination complex of manganese(Ⅱ) bipyridine complexes([Mn(bpy)2]2+), via a simple ion exchange process. The resulting I-COFs can act as effective heterogeneous catalysts for epoxidation reactions. We envisage that with this type of ionic architecture, a variety of other functional cations could be exchanged into the frameworks, thus making the COF a versatile platform for different applications.展开更多
Objective To evaluate the effect of carotid artery stenting combined with nimodipine on cerebral hemodynamics by comparing and analyzing the change of anterior cerebral blood flow before and after treatment through tr...Objective To evaluate the effect of carotid artery stenting combined with nimodipine on cerebral hemodynamics by comparing and analyzing the change of anterior cerebral blood flow before and after treatment through transcrania Doppler (TCD). Methods Twenty patients with ischemic cerebrovascnlar disease were detected in blood flow velocity of bilateral middle cerebral arteries (MCA) and anterior cerebral arteries (ACA) and artery pulsatility index with TCD before and two weeks after treatment. Results After treatment, TCD examination showed dynamic changes in blood flow significantly, lpsilateral MCA flow velocity significantly increased; ipsilateral ACA flow velocity did not change significantly; there was no significant increase in the contralateral MCA flow velocity; flow rate decreased significantly in contralateral ACA. Conclusion Carotid artery stenting combined with nimodipine treatment can cause anterior cerebral hemodynamic changes in ipsilateral hemisphere and significantly improve blood flow展开更多
基金Key Project of Science and Technology Commission of Shanghai Municipality(No.11231202100)
文摘Urban highway runoff samples from seventeen rainfall events were collected in Shanghai in 2011. The concentrations of ten heavy metals and sixteen polycyclic aromatic hydrocarbons PAHs are analyzed. The results show that the heavy metal concentrations range within 0.50 to 51.80 As 0 to 20.80 Se 13.67 to 445.80 Zn 0 to 44.20 Pb 0 to 15.80 Ni 39.58 to 264.20 Fe 0 to 253.00 Mn 0 to 8.20 Cr 0 to 124.20 Cu and 159.83 to 536.40 μg/L Al . Se Pb Mn and Al concentrations in most samples exceed their corresponding criterion continuous concentrations CCCs while Zn and Cu concentrations exceed their criterion maximum concentrations CMCs .The concentrations ofΣPAHs range within 37.25 to 114.57 ng/L and concentrations of PAHs are all below their corresponding CCCs.Cu Zn and ΣPAHs show the first flush phenomenon. Analysis results of the modified Nemerow index method NIM indicate that runoff from eight rainfall events may have very strong biological toxicity effects four have strong effects three have moderate effects and only two have insignificant effects.Therefore it is concluded that urban highway runoff is a significant pollution source to aquatic ecosystems and needs immediate purification.
基金supported by the National Natural Science Foundation of China(21473196,21676264)the 100-Talents Program of CASthe State Key Laboratory of Fine Chemicals,Dalian University of Technology(KF1415)~~
文摘As an emerging class of crystalline porous materials, covalent organic frameworks(COFs) have been widely used as catalysts or catalyst supports. Flexible regulation of the pores and easy introduction of functional active sites onto the skeleton of COFs make them promising platforms for many catalysis applications. However, only a single function is generally observed in these COFs. Herein, we synthesized a negatively charged ionic COF(I-COF) and successfully incorporated functionalized counter ions, that is, metallic Mn2+ and a coordination complex of manganese(Ⅱ) bipyridine complexes([Mn(bpy)2]2+), via a simple ion exchange process. The resulting I-COFs can act as effective heterogeneous catalysts for epoxidation reactions. We envisage that with this type of ionic architecture, a variety of other functional cations could be exchanged into the frameworks, thus making the COF a versatile platform for different applications.
基金Supported by the Shaanxi Scientific and Technical Plan(2009K18-02)
文摘Objective To evaluate the effect of carotid artery stenting combined with nimodipine on cerebral hemodynamics by comparing and analyzing the change of anterior cerebral blood flow before and after treatment through transcrania Doppler (TCD). Methods Twenty patients with ischemic cerebrovascnlar disease were detected in blood flow velocity of bilateral middle cerebral arteries (MCA) and anterior cerebral arteries (ACA) and artery pulsatility index with TCD before and two weeks after treatment. Results After treatment, TCD examination showed dynamic changes in blood flow significantly, lpsilateral MCA flow velocity significantly increased; ipsilateral ACA flow velocity did not change significantly; there was no significant increase in the contralateral MCA flow velocity; flow rate decreased significantly in contralateral ACA. Conclusion Carotid artery stenting combined with nimodipine treatment can cause anterior cerebral hemodynamic changes in ipsilateral hemisphere and significantly improve blood flow