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1.
Chemosphere ; 205: 156-165, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29689529

ABSTRACT

Maize straw modified by iron and manganese oxides was synthesized via a simple and environmentally friendly method. Three maize straw materials, the original maize straw, maize straw modified by manganese oxides and maize straw modified by iron and manganese oxides, were detected by SEM, BET, XPS, XRD and FTIR. The results showed that maize straw was successfully modified and maize straw modified by iron and manganese oxides has a larger surface area than MS. According to the experimental data, the sorption trend could conform to the pseudo-second-order kinetic model well, and the sorption ability of tylosin on sorbents followed the order of original maize straw < maize straw modified by manganese oxides < maize straw modified by iron and manganese oxides. The study indicated that manganese oxides and iron-manganese oxides could significantly enhance the sorption capacity of original maize straw. The sorption isotherm data of tylosin on original maize straw fit a linear model well, while Freundlich models were more suitable for maize straw modified by manganese oxides and maize straw modified by iron and manganese oxides. The pH, ionic strength and temperature can affect the sorption process. The sorption mechanisms of tylosin on iron and manganese oxides modified maize straw were attribute to the surface complexes, electrostatic interactions, H bonding and hydrophobic interactions.


Subject(s)
Iron/chemistry , Manganese Compounds/chemistry , Oxides/chemistry , Tylosin/isolation & purification , Water Pollutants, Chemical/isolation & purification , Water Purification/methods , Water/chemistry , Zea mays/chemistry , Tylosin/chemistry , Water Pollutants, Chemical/chemistry
3.
Environ Sci Pollut Res Int ; 25(12): 11754-11766, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29442310

ABSTRACT

Ag/Bi2WO6/graphene oxide composite with excellent photocatalytic properties was successfully prepared by hydrothermal-photoreduction synergistic method and is applied in antibiotics degradation. The structure and properties of as-prepared photocatalysts were characterized by Fourier infrared spectrum (FTIR), X-ray photoelectron spectroscopy (XPS), specific surface area analyzer (BET), scanning electron microscopy (SEM), X-ray diffraction (XRD), and atomic force microscope (AFM). The results indicated that Ag and Bi2WO6 were uniformly loaded on the surface of graphene oxide. In addition, graphene oxide with conjugated carbon network structures has been applied as a photocatalyst supporter for the high electronic conductivity and the large reactive sites. Compared with the pure graphene oxide, the as-prepared Ag/Bi2WO6/graphene oxide catalyst exhibited excellent degradation efficiency and stability for degrading tylosin under Xe lamp irradiation. Under simulated sunlight irradiation, the photodegradation efficiency of tylosin by Ag/Bi2WO6/graphene oxide achieved at 98% within 2 h, compared to 50% by pure graphene oxide. The excellent photodegradation ability is caused by the synergetic effect of Ag, Bi2WO6, and graphene oxide nanoparticles.


Subject(s)
Anti-Bacterial Agents/chemistry , Bismuth/chemistry , Environmental Pollutants/chemistry , Photolysis , Silver/chemistry , Sunlight , Tungsten Compounds/chemistry , Tylosin/chemistry , Catalysis , Graphite/chemistry , Microscopy, Electron, Scanning , Nanoparticles/chemistry , Organic Chemicals , Oxides/chemistry , Photoelectron Spectroscopy , X-Ray Diffraction
4.
Ecotoxicol Environ Saf ; 152: 16-23, 2018 May 15.
Article in English | MEDLINE | ID: mdl-29355772

ABSTRACT

MS-ZnS and MS-ZnS:Mn complexes were synthesized via a simple method. The results showed that sulfide was successfully loaded on the maize straw. The results of fitting the experimental data showed that the sorption conforms to the pseudo-second-order kinetics, and the TYL sorption on MS fit the Henry model well, but the Freundlich model was more suited to MS-ZnS and MS-ZnS:Mn. In addition, the kf values of MS-ZnS (206.0(mg/kg)/(mg/L)n) and MS-ZnS:Mn (382.5(mg/kg)/(mg/L)n) were significantly greater than that of MS (72.2(mg/kg)/(mg/L)n), indicating that ZnS and ZnS:Mn could improve the sorption capacity of TYL on MS. The pH, ionic strength and temperature influence the sorption process, and the sorption ability of TYL on MS-ZnS and MS-ZnS:Mn showed little change when the solution pH was > 5; the amount of TYL sorption on the adsorbents gradually decreased with the increasing concentration of KNO3. Electrostatic interactions, H bonding and hydrophobic interactions are involved in the sorption of TYL on MS, MS-ZnS and MS-ZnS:Mn, and compared with MS, the main mechanism is surface complexation. This research can provide technical support for the utilization of biomass and the restoration of water polluted by antibiotics.


Subject(s)
Models, Theoretical , Sulfides/chemistry , Tylosin/analysis , Water Pollutants, Chemical/analysis , Zea mays/chemistry , Adsorption , Hydrogen-Ion Concentration , Kinetics , Osmolar Concentration , Water/chemistry
5.
Lancet ; 389(10074): 1151-1164, 2017 03 18.
Article in English | MEDLINE | ID: mdl-27856085

ABSTRACT

The Lancet Countdown: tracking progress on health and climate change is an international, multidisciplinary research collaboration between academic institutions and practitioners across the world. It follows on from the work of the 2015 Lancet Commission, which concluded that the response to climate change could be "the greatest global health opportunity of the 21st century". The Lancet Countdown aims to track the health impacts of climate hazards; health resilience and adaptation; health co-benefits of climate change mitigation; economics and finance; and political and broader engagement. These focus areas form the five thematic working groups of the Lancet Countdown and represent different aspects of the complex association between health and climate change. These thematic groups will provide indicators for a global overview of health and climate change; national case studies highlighting countries leading the way or going against the trend; and engagement with a range of stakeholders. The Lancet Countdown ultimately aims to report annually on a series of indicators across these five working groups. This paper outlines the potential indicators and indicator domains to be tracked by the collaboration, with suggestions on the methodologies and datasets available to achieve this end. The proposed indicator domains require further refinement, and mark the beginning of an ongoing consultation process-from November, 2016 to early 2017-to develop these domains, identify key areas not currently covered, and change indicators where necessary. This collaboration will actively seek to engage with existing monitoring processes, such as the UN Sustainable Development Goals and WHO's climate and health country profiles. The indicators will also evolve over time through ongoing collaboration with experts and a range of stakeholders, and be dependent on the emergence of new evidence and knowledge. During the course of its work, the Lancet Countdown will adopt a collaborative and iterative process, which aims to complement existing initiatives, welcome engagement with new partners, and be open to developing new research projects on health and climate change.


Subject(s)
Climate Change , Global Health , Health Policy , Conservation of Natural Resources , Environmental Biomarkers , Humans
7.
Ambio ; 41(3): 247-61, 2012 May.
Article in English | MEDLINE | ID: mdl-22038320

ABSTRACT

The rapid development of parks and ecotourism in China has attracted worldwide attention, not only for the beauty of the landscape that the parks are protecting but also for their abundant and often unique biodiversity. However, in some areas, the development of ecotourism has actually led to the degradation of local ecological, economic, and social systems. Using National Forest Parks for demonstration, this article analyzes the current political, institutional, legal, environmental, and economic issues concerning National Parks in China, and examines their potential future development. Although the intention of National Park systems in China is to raise environmental quality, and to protect biodiversity and social livelihoods, their success has varied. Future success will be measured by their capacity to reduce poverty, to promote long-term rehabilitation of wildlife habitats, and to simultaneously protect Chinese culture and biodiversity.


Subject(s)
Commerce , Conservation of Natural Resources/economics , Conservation of Natural Resources/methods , Ecosystem , China , Time Factors , Travel
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