采用盆栽土培法研究Cd(0~50mg/kg)单一污染及与Cu(0~500mg/kg)复合污染对苍耳(Xanthium sibiricum Patrin ex Widder)生长及叶绿素荧光特性的影响。生长特性研究结果表明:Cd(<30mg/kg)与Cu(<50mg/kg)复合污染时,生长指标(生物量...采用盆栽土培法研究Cd(0~50mg/kg)单一污染及与Cu(0~500mg/kg)复合污染对苍耳(Xanthium sibiricum Patrin ex Widder)生长及叶绿素荧光特性的影响。生长特性研究结果表明:Cd(<30mg/kg)与Cu(<50mg/kg)复合污染时,生长指标(生物量、根系表面积及株高)显著大于单一Cu或Cd污染下的生长指标,且随着Cd与Cu复合浓度的增加而逐渐下降;Cd与Cu复合污染在低浓度下表现为拮抗效应,高浓度下表现为协同作用。生理特性研究结果表明:与单一Cd污染相比,Cd(<50mg/kg)与Cu(<50mg/kg)复合污染时,最大荧光产量(Fm)、光化学效率(Fv/Fm)及电子传递速率(ETR)明显较大,而初始荧光(Fo)明显较小(p<0.05),表明Cu能一定程度上缓解Cd对苍耳的毒害作用。苍耳对重金属的富集及转移系数计算结果表明:与单一Cd污染相比,Cd(<15mg/kg)与Cu(<100mg/kg)复合污染时,苍耳对Cd的富集系数明显较大,表明Cu能有效促进苍耳对Cd的富集;Cd(<50mg/kg)与Cu(<100mg/kg)复合污染时,苍耳对Cd的转移系数明显较小,表明Cu不能有效促进苍耳把Cd从地下部转移到地上部。苍耳可以考虑作为修复Cd-Cu复合污染的候选植物种之一。展开更多
In this paper, we report the fabrication of the photocatalysts composed of Cu2O nanobelts and nanoporous Cu(NP Cu)substrate, which is obtained by soaking the NP Cu in dehydrated ethanol. The NP Cu substrate is achieve...In this paper, we report the fabrication of the photocatalysts composed of Cu2O nanobelts and nanoporous Cu(NP Cu)substrate, which is obtained by soaking the NP Cu in dehydrated ethanol. The NP Cu substrate is achieved by dealloying of Ti40.6Zr9.4Cu40.6Ni6.3Sn3.1 amorphous ribbons in HF solutions. The dealloying process is considered to be a thermally activated process, obeying the Arrhenius law. The surface diffusivity increases with increasing dealloying temperature and concentration of HF solutions. The activation energy of the diffusion of Cu adatoms is estimated to be 76.4 kJ/mol. The Cu2O nanobelts with the width of 10–15 nm and the length of about 1 lm are formed on the surface of NP Cu after immersion in dehydrated ethanol. The photocatalysts of Cu2O on nanoporous Cu exhibit superior photocatalytic activity toward the degradation of methyl orange and methylene blue under the irradiation of the sunlight due to the coexistence of Cu2O semiconductor nanobelts and large amount of heterojunctions as flowing path for photoelectrons.展开更多
随着5G RAN 3层架构的逐渐明确,原4G时代的BBU拆分为CU和DU,其中非实时的无线高层协议栈功能引入到CU,物理层功能和实时性需求的层2功能引入到DU,部分实时性更高的物理层功能并入RRU。5G NR基站的规划正是基于新的3层架构,通过从4G到5G ...随着5G RAN 3层架构的逐渐明确,原4G时代的BBU拆分为CU和DU,其中非实时的无线高层协议栈功能引入到CU,物理层功能和实时性需求的层2功能引入到DU,部分实时性更高的物理层功能并入RRU。5G NR基站的规划正是基于新的3层架构,通过从4G到5G RAN架构的演进、CU/DU/RRU多种部署组合方式、NR基站多种部署方式资源需求、场景应用等多方面分析,论述了5GNR基站部署需要关注的问题。展开更多
文摘采用盆栽土培法研究Cd(0~50mg/kg)单一污染及与Cu(0~500mg/kg)复合污染对苍耳(Xanthium sibiricum Patrin ex Widder)生长及叶绿素荧光特性的影响。生长特性研究结果表明:Cd(<30mg/kg)与Cu(<50mg/kg)复合污染时,生长指标(生物量、根系表面积及株高)显著大于单一Cu或Cd污染下的生长指标,且随着Cd与Cu复合浓度的增加而逐渐下降;Cd与Cu复合污染在低浓度下表现为拮抗效应,高浓度下表现为协同作用。生理特性研究结果表明:与单一Cd污染相比,Cd(<50mg/kg)与Cu(<50mg/kg)复合污染时,最大荧光产量(Fm)、光化学效率(Fv/Fm)及电子传递速率(ETR)明显较大,而初始荧光(Fo)明显较小(p<0.05),表明Cu能一定程度上缓解Cd对苍耳的毒害作用。苍耳对重金属的富集及转移系数计算结果表明:与单一Cd污染相比,Cd(<15mg/kg)与Cu(<100mg/kg)复合污染时,苍耳对Cd的富集系数明显较大,表明Cu能有效促进苍耳对Cd的富集;Cd(<50mg/kg)与Cu(<100mg/kg)复合污染时,苍耳对Cd的转移系数明显较小,表明Cu不能有效促进苍耳把Cd从地下部转移到地上部。苍耳可以考虑作为修复Cd-Cu复合污染的候选植物种之一。
基金financially supported by the National Natural Science Foundation of China under Grant No.51671106the Natural Science Foundation of Jiangsu Province under Grant Nos.BK20171424 and BK2015153.
文摘In this paper, we report the fabrication of the photocatalysts composed of Cu2O nanobelts and nanoporous Cu(NP Cu)substrate, which is obtained by soaking the NP Cu in dehydrated ethanol. The NP Cu substrate is achieved by dealloying of Ti40.6Zr9.4Cu40.6Ni6.3Sn3.1 amorphous ribbons in HF solutions. The dealloying process is considered to be a thermally activated process, obeying the Arrhenius law. The surface diffusivity increases with increasing dealloying temperature and concentration of HF solutions. The activation energy of the diffusion of Cu adatoms is estimated to be 76.4 kJ/mol. The Cu2O nanobelts with the width of 10–15 nm and the length of about 1 lm are formed on the surface of NP Cu after immersion in dehydrated ethanol. The photocatalysts of Cu2O on nanoporous Cu exhibit superior photocatalytic activity toward the degradation of methyl orange and methylene blue under the irradiation of the sunlight due to the coexistence of Cu2O semiconductor nanobelts and large amount of heterojunctions as flowing path for photoelectrons.
文摘随着5G RAN 3层架构的逐渐明确,原4G时代的BBU拆分为CU和DU,其中非实时的无线高层协议栈功能引入到CU,物理层功能和实时性需求的层2功能引入到DU,部分实时性更高的物理层功能并入RRU。5G NR基站的规划正是基于新的3层架构,通过从4G到5G RAN架构的演进、CU/DU/RRU多种部署组合方式、NR基站多种部署方式资源需求、场景应用等多方面分析,论述了5GNR基站部署需要关注的问题。