A modified Hummer's method was adopted for the synthesis of graphene oxide(GO) and reduced graphene oxide(rGO). It was revealed that the modified method is effective for the production of GO and rGO from graphite. Transmission electron microscopy(TEM) images of GO and rGO showed a sheet-like morphology. Because of the presence of oxygenated functional groups on the carbon surface, the interlayer spacing of the prepared GO was higher than that of rGO. The presence of \OH and C_O groups in the Fourier transform infrared spectra(FTIR) spectrum and G-mode and 2D-mode in Raman spectra confirmed the synthesis of GO and rGO. rGO(292.6 m~2/g) showed higher surface area than that of GO(236.4 m~2/g). The prepared rGO was used as an adsorbent for benzene and toluene(model pollutants of volatile organic compounds(VOCs)) under dynamic adsorption/desorption conditions. rGO showed higher adsorption capacity and breakthrough times than GO. The adsorption capacity of rGO for benzene and toluene was 276.4 and 304.4 mg/g, respectively.Desorption experiments showed that the spent rGO can be successfully regenerated by heating at 150.0°C. Its excellent adsorption/desorption performance for benzene and toluene makes rGO a potential adsorbent for VOC adsorption. 相似文献
Objective: Adults 65 years of age and older comprise the fastest growing demographic in the United States. As substance use is projected to increase in this population, there is concern that more seniors will drive under the influence of impairing drugs. The purpose of this analysis was to characterize the drug and alcohol usage among senior drivers fatally injured (FI) in traffic collisions.
Methods: Data from the Fatality Analysis Reporting System were analyzed from 2008 to 2012. Commonly used classes and specific drugs were explored. Rates of drug use, multiple drugs, concomitant drug and alcohol use, and alcohol use alone were generated using Poisson regression with robust error variance estimation. Rates were compared to a reference population of FI middle-aged drivers (30 to 50 years old) using rate ratios.
Results: Drug use among FI senior drivers occurred in 20.0% of those tested. Among drug-positive FI senior drivers, narcotics and depressants were frequent. The prevalence of testing positive for any drug, multiple drugs, combined drug and alcohol, and alcohol use alone among FI seniors were 47% less (relative risk [RR] = 0.53, 95% confidence interval [CI], 0.47, 0.62), 59% less (RR = 0.41, 95% CI, 0.34, 0.51), 87% less (RR = 0.13, 95% CI, 0.09, 0.19), and 77% less (RR = 0.23, 95% CI, 0.19, 0.28), respectively, compared to FI middle-aged drivers.
Conclusions: Though overall drug use is less common among FI senior drivers relative to FI middle-aged drivers, driving under the influence of drugs may be a relevant traffic safety concern in a portion of this population. 相似文献
Lambda-cyhalothrin(LCT),one of the type II pyrethroids,has been widely used throughout the world.The estrogenic effect of LCT to increase cell proliferation has been well established.However,whether the estrogenic effect of LCT will influence neurodevelopment has not been investigated.In addition,17β-Estradiol(E2)plays a crucial role in neurodevelopment and induces an increase in synaptic proteins.The post-synaptic density 95(PSD95)protein,which is involved in the development of the structure and function of new spines and localized with estrogen receptor α(ERα)at the post-synaptic density(PSD),was detected in our study by using hippocampal neuron cell line HT22.We found that LCT up-regulated PSD95 and ERα expression,estrogen receptor(ER)antagonist ICI182,780 and phosphatidylinositol-4;5-bisphosphate 3-kinase(PI3K)inhibitor LY294,002 blocked this effect.In addition,LCT disrupted the promotion effect of E2 on PSD95.To investigate whether the observed changes are caused by ERα-dependent signaling activation,we next detected the effects of LCT on the ERα-mediated PI3K-Protein kinase B(PKB/Akt)-eukaryotic initiation factor(e IF)4E-binding protein 1(4E-BP1)pathway.There existed an activation of Akt and the downstream factor 4E-BP1 after LCT treatment.In addition,LCT could disrupt the activation effect of E2 on the Akt pathway.However,no changes in c AMP response element-binding protein(CREB)activation and PSD95 messenger ribonucleic acid(m RNA)were observed.Our findings demonstrated that LCT could increase the PSD95 protein level via the ERα-dependent Akt pathway,and LCT might disrupt the up-regulation effect of E2 on PSD95 protein expression via this signaling pathway. 相似文献