The photocatalytic degradation of norfloxacin by bismuth tungstate(Bi2WO6)with different hierarchical architectures wasinvestigated under visible light irradiation.Bi2WO6was prepared by hydrothermal method with the re...The photocatalytic degradation of norfloxacin by bismuth tungstate(Bi2WO6)with different hierarchical architectures wasinvestigated under visible light irradiation.Bi2WO6was prepared by hydrothermal method with the reaction solution pH rangingfrom4to11.The relatively ultrathin Bi2WO6nanoflakes prepared at pH4showed excellent adsorption and photodegradationefficiency towards norfloxacin.The characterization results showed that Bi2WO6prepared at pH4had a larger specific area andfaster photo-generated carrier separation rate.The decay rate reached the maximum in weak alkaline reaction solution,which couldbe attributed to the presence of moderate OH-anions.The present study demonstrated that the smaller size of Bi2WO6could be anefficient photocatalyst on the degradation of norfloxacin in the aquatic environment.展开更多
详述M apG IS软件在长沙市土地详查数据库建设中的应用,对数据库建设中碰到的图形、图像处理,数据库建设等技术性问题进行了深入细致的研究,并提出利用M apG IS结合AutoCAD软件对数据进行矢量化可大大提高工作效率,节约劳动成本,并对土...详述M apG IS软件在长沙市土地详查数据库建设中的应用,对数据库建设中碰到的图形、图像处理,数据库建设等技术性问题进行了深入细致的研究,并提出利用M apG IS结合AutoCAD软件对数据进行矢量化可大大提高工作效率,节约劳动成本,并对土地详查数据库的建设起到积极的指导作用。展开更多
The remediation of Pb-contaminated port sediment by biosurfactant from a new isolated Bacillus sp.G1was studied.ThePb removal efficiencies were investigated under multi-levels of water-solid ratio,pH and ionic strengt...The remediation of Pb-contaminated port sediment by biosurfactant from a new isolated Bacillus sp.G1was studied.ThePb removal efficiencies were investigated under multi-levels of water-solid ratio,pH and ionic strength.Result showed thatexchangeable speciation of Pb could be removed by maximum removal capacity of76.8mg/g after leaching.The Langmuir isothermreflected the adsorption process best to fit the experimental adsorption equilibrium data.Fourier transform infrared spectra(FTIR)indicated that C=O and-CH3may be the functional groups.Scanning electron microscopy(SEM)analysis showed that thesurface of the port sediment became much smoother after adsorption interaction,which reflected that the complexation between Pbions and biosurfactant was more stable.The results indicated that the biosurfactant of Bacillus sp.G1could remove Pb effectivelyfrom the Pb-contaminated port sediment(PCPS)and suggested a novel method for PCPS remediation.展开更多
An enriched and domesticated bacteria consortium of sulfate-reducing bacteria(SRB)was used to treat wastewater from zinc pyrithione(ZPT)production,and the effects of different reaction parameters on sulfate reduction ...An enriched and domesticated bacteria consortium of sulfate-reducing bacteria(SRB)was used to treat wastewater from zinc pyrithione(ZPT)production,and the effects of different reaction parameters on sulfate reduction and zinc precipitation were evaluated.The single-factor experimental results showed that the removal rates of Zn2+and24SO?decreased with an increased ZPT concentration ranging from3.0to5.0mg/L.Zn2+and24SO?in wastewater were effectively removed under the conditions of30?35°C,pH7?8and an inoculum concentration of10%?25%.The presence of Fe0in the SRB system enhanced Zn2+and24SO?removal and may increase the resistance of SRB to the toxicity of Zn2+and ZPT in wastewater.A Box?Behnken design was used to evaluate the influence of the main operating parameters on the removal rate of24SO?.The optimum parameter values were found to be pH7.45,33.61°C and ZPT concentration of0.62mg/L,and the removal rate of24SO?reached a maximum of91.62%under these optimum conditions.展开更多
Climate change and human activities influence species biodiversity by altering their habitats. This paper quantitatively analyzed the effects of climate change on a migratory bird. The Lesser White-fronted Goose(LWfG)...Climate change and human activities influence species biodiversity by altering their habitats. This paper quantitatively analyzed the effects of climate change on a migratory bird. The Lesser White-fronted Goose(LWfG), a species which migrates via the middle and lower reaches of the Yangtze River region, is an herbivorous species of high ecological value. It is an endangered species threatened by climate change and human activities, so comprehensive information about its distribution is required. To assess the effectiveness of conservation of the LWfG under climate change, both climate variables and human activities are often used to predict the potential changes in the distribution and habitat suitability for LWfG. In this work, the current scenario and the Global Circulation Models(GCMs) climate scenarios were used to simulate the future distribution of the species. However, besides climate change and human activities, the spatial pattern of plants surrounding the wetland is also known to be closely related to the distribution of LWfG. Therefore, the distribution model results of six plant species related to LWfG’s diet selection were used as environment variables to reflect the changes of suitable LWfG habitat. These environmental variables significantly improved the model’s performance for LWfG, since the birds were clearly influenced by the plant distribution factors. Meanwhile, the suitable habitat area decreases by 2070 in GCM models under two representative concentration pathways scenarios(RCP2.6 and RCP8.5). More appropriate management and conservation policies should be taken to adapt to future climate change. These adjustments include modifications of the size, shape and use of the conservation area for this species.展开更多
基金Projects(51579096,51222805,51521006,51508175) supported by the National Natural Science Foundation of ChinaProject supported by the National Program for Support of Top-Notch Young Professionals of China+1 种基金Project(NCET–11–0129) supported by the Program for New Century Excellent Talents in University from the Ministry of Education of ChinaProject(CX2015B095) supported by the Hunan Province Innovation Foundation for Postgraduate,China
文摘The photocatalytic degradation of norfloxacin by bismuth tungstate(Bi2WO6)with different hierarchical architectures wasinvestigated under visible light irradiation.Bi2WO6was prepared by hydrothermal method with the reaction solution pH rangingfrom4to11.The relatively ultrathin Bi2WO6nanoflakes prepared at pH4showed excellent adsorption and photodegradationefficiency towards norfloxacin.The characterization results showed that Bi2WO6prepared at pH4had a larger specific area andfaster photo-generated carrier separation rate.The decay rate reached the maximum in weak alkaline reaction solution,which couldbe attributed to the presence of moderate OH-anions.The present study demonstrated that the smaller size of Bi2WO6could be anefficient photocatalyst on the degradation of norfloxacin in the aquatic environment.
基金Project(2016M590348) supported by China Postdoctoral Science FoundationProjects(41301154,41271332) supported by the National Natural Science Foundation of China
文摘The remediation of Pb-contaminated port sediment by biosurfactant from a new isolated Bacillus sp.G1was studied.ThePb removal efficiencies were investigated under multi-levels of water-solid ratio,pH and ionic strength.Result showed thatexchangeable speciation of Pb could be removed by maximum removal capacity of76.8mg/g after leaching.The Langmuir isothermreflected the adsorption process best to fit the experimental adsorption equilibrium data.Fourier transform infrared spectra(FTIR)indicated that C=O and-CH3may be the functional groups.Scanning electron microscopy(SEM)analysis showed that thesurface of the port sediment became much smoother after adsorption interaction,which reflected that the complexation between Pbions and biosurfactant was more stable.The results indicated that the biosurfactant of Bacillus sp.G1could remove Pb effectivelyfrom the Pb-contaminated port sediment(PCPS)and suggested a novel method for PCPS remediation.
基金Project(2015DFG92750)supported by the International S&T Cooperation Program of ChinaProjects(51278464,51478172)supported by the National Natural Science Foundation of ChinaProject(2014GK1012)supported by the Department of Science and Technology of Hunan Province,China
文摘An enriched and domesticated bacteria consortium of sulfate-reducing bacteria(SRB)was used to treat wastewater from zinc pyrithione(ZPT)production,and the effects of different reaction parameters on sulfate reduction and zinc precipitation were evaluated.The single-factor experimental results showed that the removal rates of Zn2+and24SO?decreased with an increased ZPT concentration ranging from3.0to5.0mg/L.Zn2+and24SO?in wastewater were effectively removed under the conditions of30?35°C,pH7?8and an inoculum concentration of10%?25%.The presence of Fe0in the SRB system enhanced Zn2+and24SO?removal and may increase the resistance of SRB to the toxicity of Zn2+and ZPT in wastewater.A Box?Behnken design was used to evaluate the influence of the main operating parameters on the removal rate of24SO?.The optimum parameter values were found to be pH7.45,33.61°C and ZPT concentration of0.62mg/L,and the removal rate of24SO?reached a maximum of91.62%under these optimum conditions.
基金The National Natural Science Foundation of China(51679082,51979101,51479072)The Hunan Science&Technology Innovation Program(2018RS3037)The Natural Science Foundation of Hunan Province(2019JJ20002).
文摘Climate change and human activities influence species biodiversity by altering their habitats. This paper quantitatively analyzed the effects of climate change on a migratory bird. The Lesser White-fronted Goose(LWfG), a species which migrates via the middle and lower reaches of the Yangtze River region, is an herbivorous species of high ecological value. It is an endangered species threatened by climate change and human activities, so comprehensive information about its distribution is required. To assess the effectiveness of conservation of the LWfG under climate change, both climate variables and human activities are often used to predict the potential changes in the distribution and habitat suitability for LWfG. In this work, the current scenario and the Global Circulation Models(GCMs) climate scenarios were used to simulate the future distribution of the species. However, besides climate change and human activities, the spatial pattern of plants surrounding the wetland is also known to be closely related to the distribution of LWfG. Therefore, the distribution model results of six plant species related to LWfG’s diet selection were used as environment variables to reflect the changes of suitable LWfG habitat. These environmental variables significantly improved the model’s performance for LWfG, since the birds were clearly influenced by the plant distribution factors. Meanwhile, the suitable habitat area decreases by 2070 in GCM models under two representative concentration pathways scenarios(RCP2.6 and RCP8.5). More appropriate management and conservation policies should be taken to adapt to future climate change. These adjustments include modifications of the size, shape and use of the conservation area for this species.