Degradation of ampicillin antibiotic in aqueous solution by ZnO/polyaniline nanocomposite as photocatalyst under sunlight irradiation

PURPOSE AND METHOD: ZnO/polyaniline nanocomposite in core-shell structure was prepared by the synthesis and adsorption of polyaniline chains on the structure of ZnO nanoparticles. Fourier transform infrared and ultraviolet-visible (UV-Vis) spectroscopy, X-ray diffraction patterns, field emission scanning electron microscopy, and transmission electron microscopy were used to characterize the composition and structure of the nanocomposite. The nanocomposite was used as an active photocatalyst for photodegradation and removal of ampicillin in aqueous solution. RESULTS: UV-Vis spectroscopy studies showed that ZnO/polyaniline nanocomposite absorbs visible light irradiation as well as ultraviolet spectrum, and therefore, it can be photoactivated under visible and ultraviolet lights. The photocatalytic activity of ZnO/polyaniline nanocomposite in degradation of ampicillin molecules in aqueous solution under natural sunlight irradiation was evaluated and compared with that of ZnO nanoparticles and pristine polyaniline. The ZnO/polyaniline core-shell nanocomposite exhibited higher photocatalytic activity compared to ZnO nanoparticles and pristine polyaniline. The effect of operating conditions (pH, ZnO/polyaniline nanocomposite dosage, and ampicillin concentration) in the photocatalytic degradation of ampicillin using ZnO/polyaniline nanocomposite was investigated. The optimum conditions for maximum efficiency of ampicillin degradation under 120 min sunlight irradiation were found as 10 mg L(-1) dosage of ZnO/polyaniline nanocomposite, ampicillin concentration of 4.5 mg L(-1), and solution pH?=?5. Under optimum operating conditions, degradation efficiency was reached to 41% after 120 min of exposure to the sunlight irradiation.     

Synthesis of CS/PVA Biodegradable Composite Nanofibers as a Microporous Material with Well Controllable Procedure Through Electrospinning

In this study, we have showed a facile route for fabrication of a novel microporous material based on chitosan (CS) and poly(vinyl alcohol) (PVA) biodegradable nanofibers that have high specific surface area, considerable porosity, and small diameter. Scanning electron microscopy, thermogravimetric analysis, differential scanning calorimetry, fourier transform infrared spectroscopy, Brunauer–Emmett–Teller surface area analysis, and CHNS/O elemental analyser were applied to characterize the fabricated CS/PVA composite nanofibers. Moreover, the influences of spinning conditions including concentration, voltage, electrospinning distance, and flow rate, on size distribution and pore diameter of the final product were systematically studied using 2^k?1 factorial design experiments, and the response surface optimization was used for determining the best synthesis parameter. The results obtained from 2^K?1 factorial design experiments showed that electrospinning parameters influenced the size distribution and pore diameter of the CS/PVA microporous material. Based on the response surface methodology, the CS/PVA product could be obtained with a high microporous diameter of 1.8 nm and a small diameter distribution of 15.0 nm under optimized conditions. The obtained results showed that the fabricated samples could be utilized in different applications.     

A bibliometric study on blockchain-based supply chain: a theme analysis,adopted methodologies,and future research agenda

Environmental Science and Pollution Research - The emergence of the underlying blockchain technology of bitcoin has gained extensive attention from researchers and practitioners. As distributed...     

The need for constructing endangered fish habitats that conform to climate-driven flow changes in a western U.S. river

Warmwater fish habitat in the San Juan River of the southwestern United States has been reduced by over 30% as a result of water depletion, reservoir inundation, and cold-water dam releases combined with drought-related changes in hydrology. This reduction and a suite of other factors have contributed to declines in native fish populations including the federally endangered Colorado Pikeminnow (Ptychocheilus lucius) and Razorback Sucker (Xyrauchen texanus). Conservation efforts for these species include determining flow needs; protecting, managing, and augmenting habitats; and stocking hatchery fish. But the young of stocked fish have low survival due largely to a paucity of nursery habitat not being reformed and maintained under current conditions. Flow recommendations for Navajo Dam releases designed to mimic the river's natural hydrograph have not been met due to water shortages, and the desired outcomes of increased channel complexity and enhanced fish habitat have not been observed. Forecasted hydrology that includes ongoing drought shows that achieving the flow targets through further dam reoperations is unlikely. Mechanical construction of early life-stage habitats is a highly recommended complement to flow management for offsetting the effects of flow reduction and habitat loss. Habitats with features that are effective and resilient under a range of flows are important in counterbalancing the effects of climate change.     

Optimizing different adaptive strategies by using crop growth modeling under IPCC climate change scenarios for sustainable wheat production

Environment, Development and Sustainability - Crop production is highly sensitive to climate. It is affected by long-term trends in average rainfall and temperature, inter-annual climate...     

Tramadol abuse among workers in an industrial city in mid-Nile Delta region,Egypt

Environmental Science and Pollution Research - Tramadol abuse is an increasingly alarming phenomenon among Egyptian Community especially among workers and drivers. Study profile and factors...     

Empirics on heterogeneous links among urbanization,the intensity of electric power consumption,water-based emissions,and economic progress in regional China

Environmental Science and Pollution Research - This study investigates the heterogeneous causal linkages between urbanization, the intensity of electric power consumption, water-based pollutant...     

Organochlorine pesticides in the surrounding soils of POPs destruction facility: source fingerprinting,human health,and ecological risks assessment

Environmental Science and Pollution Research - The elimination of persistent organic pollutants (POPs) obsolete pesticides stockpiles, particularly the organochlorine pesticides (OCPs), is one of...     

Challenges of soil erosion and sludge management for sustainable development in Indonesia

Most developing countries, particularly Indonesia, will be facing problems of sludge pressure in the next decades due to the increase in practices of legal and illegal logging as well as land and water demands. Consequently, they will also be facing the challenges of soil erosion and sludge management due to increased quantities of sludge coming from several potential sources, such as activated sludge, chemical sludge, fecal sludge and solid wastes as well as erosion and sedimentation. Although the government of Indonesia has enacted laws and policies to speed up the implementation of the programs and activities related to sludge management, the detailed practice concepts in implementing the programs need to be identified. Discussion of role-sharing amongst the related government agencies, private institutions and other stakeholders is urgent for clarifying the participation of each party in the next years to come. This paper proposes a management approach and level of responsibilities in sludge management. Implementation of zero ΔQ, zero ΔS and zero ΔP policies needs to be adopted by local and central governments. Application of sludge on the agricultural lands and other uses will promote sustainable development.     

Advanced oxidation treatment of physico-chemically pre-treated olive mill industry effluent

In this study, the applicability of physico-chemical methods was investigated for the pre-treatment of the olive mill effluents prior to the discharge into the common sewerage ending with a municipal wastewater treatment plant. The samples were taken from an olive oil industry operated as three-phase process located in Turkey. Various pre-treatment methods including acid craking, polyelectrolyte and lime additions were applied. Advanced oxidation study using Fenton's process was also investigated following pre-treatment by acid cracking and cationic polyelectrolyte. Acid cracking alone gave satisfactory treatment efficiencies and polyelectrolite additions to the acid-cracked samples enhanced treatment efficiency. Since a complete treatment plant is available at the end of the sewer system, results indicated that the effluents of the investigated industry could be discharged into the municipal sewerage in the case of total chemical oxygen demand (COD(tot)), suspended solid (SS) and volatile suspended solid (VSS) concentrations according to the Turkish Water Pollution Control Regulation after pre-treatment with 5 ppm anionic polyelectrolyte following acid cracking. The minimum COD(tot), SS and VSS removals were observed when raw wastewater was pre-treated with lime and the discharge standards to the municipal sewer system could not be met. Advanced oxidation with Fenton's process was applied after acid cracking and cationic polyelectrolyte treatment in order to investigate further reduction in chemical oxygen demand (COD) concentration for minimizing the influence of this industrial discharge on the existing municipal wastewater treatment plant. Results indicated that COD(tot) removal increased up to 89% from 74% after Fenton's oxidation for the acid cracked samples in which cationic polyelectrolite (10 ppm) was added.