Nitrogen removal from domestic sewage is usually limited by insufficient carbon source and electron donor. An economical solid carbon source was developed by composition of polyvinyl alcohol, sodium alginate, and corncob, which was utilized as external carbon source in the anaerobic anoxic oxic (AAO)-biofilter for the treatment of low carbon-to-nitrogen ratio domestic sewage, and the nitrogen removal was remarkably improved from 63.2% to 96.
View Article and Find Full Text PDFThere is a lack of understanding about the bacterial, fungal and archaeal communities' composition of solid-phase denitrification (SPD) systems. We investigated four SPD systems with different carbon sources by analyzing microbial gene sequences based on operational taxonomic unit (OTU) and amplicon sequence variant (ASV). The results showed that the corncob-polyvinyl alcohol sodium alginate-polycaprolactone (CPSP, 0.
View Article and Find Full Text PDFPhthalic acid esters (PAEs) are typical industrial chemicals used in China. PAEs have received considerable attention because of their ubiquity and potential hazard to humans and the ecology. The spatiotemporal distributions of six PAEs in the surface sediments of the Songhua River in the spring (March), summer (July), and autumn (September) are investigated in this study.
View Article and Find Full Text PDFMFC anodic denitrification is more suitable for the coexistence of organic matter and nitrate in actual sewage, but the traditional carbon source has some problems such as high cost and difficulty of dosage control in MFC. Herein, corncob and polycaprolactone (PCL) were mechanically pulverized and mixed in the system of polyvinyl alcohol and sodium alginate, and cross-linked to prepare slow-release carbon source fillers (CPSP), which were added to the MFC anolyte to realize the coupling of solid-phase denitrification and anodic denitrification. Results showed the start-up period of MFC experimental group (MFC-C) with CPSP was slightly longer than the control group (MFC-0), but MFC-C's maximum output voltage (648.
View Article and Find Full Text PDFSolid-phase denitrification (SPD) has been used in wastewater treatment plant effluent to enhance nitrate removal, and antibiotics co-existing in the effluent is a common environmental problem. In this study, it was systematically investigated the effect of single trace sulfamethoxazole (SMX)/trimethoprim (TMP) and their mixture on microbial denitrification performance, the antibiotics removal, and antibiotics resistance genes (ARGs) in corncob supported SPD system. The average denitrification rate was improved by 46.
View Article and Find Full Text PDFNitrogen in surface sediments is becoming an ecological risk to the river environment and it is essential to clarify the relationship between the different forms of nitrogen and related microorganisms. A survey was conducted to analyze the distribution characteristics of the nitrogen and related microbial community in the sediments of the Songhua River during normal season and dry season. In the surface sediments of the Songhua River, no total nitrogen (TN) pollution risk was observed according to the U.
View Article and Find Full Text PDFExternal carbon source addition is one of the effective methods for the treatment of wastewater with low carbon to nitrogen ratio (C/N). Compared with fast-release liquid carbon sources, slow-release solid carbon sources are more suitable for the denitrification process. A novel slow-release solid carbon source (corncob-polyvinyl alcohol sodium alginate- poly-caprolactone, i.
View Article and Find Full Text PDFBackground: Studies have shown the promising prospects of rosmarinic acid (RosA) for the prevention and treatment of allergic diseases.
Objective: The aim of this study was to investigate the effects of RosA on inflammatory reaction in rat models of allergic rhinitis (AR) after PM2.5 exposure.
This study investigated the effect of metacognitive regulation (McR) intervention on attention-deficit-hyperactivity disorder (ADHD) students' astronomy knowledge acquisition and learning motivation. Through a cognitive-behavioural treatment design, this study selected 97 ADHD learners who had poor academic performance. This study divided ADHD students randomly into one experimental group and one control group.
View Article and Find Full Text PDFThis study synthesized the correlation between reading strategy and reading comprehension of four categories based on Weinstein and Mayer's reading strategy model. The current meta-analysis obtained 57 effect sizes that represented 21,548 readers, and all selected materials came from empirical studies published from 1998 to 2019. Results showed that reading strategies in all the four categories had a similar correlation effect size with reading comprehension.
View Article and Find Full Text PDFAs carbon sources for the denitrification process, agricultural wastes have some problems, such as excess release of organic carbon; unclear release characteristics of nitrogen, phosphorus, and colorimetric substances; and unclear components, release mechanisms, and potential effects of the released dissolved organic matter (DOM) in the start-up period. To resolve those problems, rice straw, wheat straw, corn stalk, corncob, soybean stalk, and soybean hull were selected as denitrification carbon sources to investigate the release mechanisms and potential influences of the organic matter, secondary pollutants, and DOM. The results showed that the six agricultural wastes could be used as the denitrification carbon source.
View Article and Find Full Text PDFExposure to fine particulate matter (PM2.5) increases the incidence of allergic rhinitis (AR). microRNA (miRNA) can regulate cell proliferation, invasion and apoptosis.
View Article and Find Full Text PDFAgricultural wastes used as denitrification carbon sources have some drawbacks such as excessive organic carbon release and unclear release characteristics of nitrogen, phosphorus, and chromatic substances, which can cause adverse effects on the effluent quality during the denitrification process. The composition and surface characteristics, carbon release mechanisms, and secondary pollutant release properties of six kinds of agricultural wastes, i.e.
View Article and Find Full Text PDFThis study investigated the correlation between vocabulary knowledge and reading comprehension. To address the correlation picture under Chinese logographical scripts, the researchers investigated the potential explanation for the correlation via Reading Stage, Information Gap, Content-based Approach, and Cognition and Creativity Theory approaches. This study undertook a meta-analysis to synthesize 89 independent samples from primary school stage to Master's degree stage.
View Article and Find Full Text PDFParticulate matter 2.5 (PM) exposure can increase the prevalence of allergic rhinitis (AR), the mechanism underlying which may include oxidative stress and inflammatory response. As a ROS quenching agent, N-acetylcysteine (NAC) can attenuate the accumulation of inflammatory cells and hyper-responsiveness in animal asthma models.
View Article and Find Full Text PDFBackground: According to recent epidemiologic studies, exposure to fine particulate matter (particulate matter 2.5 ≤ µm [PM2.5]) in the air increases the incidence and severity of allergic rhinitis (AR).
View Article and Find Full Text PDFWhen low-concentration rural sewage is treated biologically, the effluent total nitrogen (TN) concentration often does not meet the discharge limit because of its low carbon-to-nitrogen ratio (C/N). To solve this problem, a laboratory-scale anoxic/oxic (A/O) biofilter packed with and activated carbon as the anoxic and aerobic column fillers (No. 2) was operated for treatment of simulated rural sewage and advanced nitrogen removal, while an ordinary gravel-packing A/O biofilter (No.
View Article and Find Full Text PDFThis longitudinal study investigated how different mediums of word explanation affected the use of English vocabulary strategies among Chinese Grade-7 students. 170 students were tested on their English receptive vocabulary size and vocabulary strategy application before and after an 8.33-month intervention.
View Article and Find Full Text PDFNitrogen (N) remains a great challenge in wastewater treatment while attempts to remove N has continuously been a research point for decades. In this study, the long-term performance of four identical-shape denitrification MBBRs (moving bed biofilm reactors) with four different configurations of cylindrical polyethylene as carriers (Φ25 × 12, Φ25 × 4, Φ15 × 15, and Φ10 × 7 mm) for advanced N removal of real reverse osmosis concentrate was investigated in great detail. The N of the real concentrate can be effectively removed by denitrification MBBRs when the pH, temperature, hydraulic retention time (HRT), C/N ratio, and filling rate are 7.
View Article and Find Full Text PDFBackground: Allergic rhinitis (AR) is a global health problem and closely related to environmental factors. Ursolic acid (UA) has potential in the treatment of allergic inflammation. The effects of UA intervention on PM2.
View Article and Find Full Text PDFBackground: Particulate matter 2.5 (PM2.5) refers to particulate matter with aerodynamic equivalent diameter less than or equal to 2.
View Article and Find Full Text PDFInt J Environ Res Public Health
February 2020
-sulfur-based heterotrophic and autotrophic denitrification (HSHAD) process was developed in free water surface constructed wetland mesocosms for the treatment of nitrate-rich agricultural runoff with low chemical oxygen demand/total nitrogen (C/N) ratio, whose feasibility and mechanism were extensively studied and compared with those of heterotrophic denitrification (HHD) mesocosms through a 273-day operation. The results showed that the heterotrophic and autotrophic denitrification can be combined successfully in HSHAD mesocosms, and achieve satisfactory nitrate removal performance. The average NO-N removal efficiency and denitrification rate of HSHAD were 94.
View Article and Find Full Text PDFThis study assesses the spatial distribution characteristics and ecological risk of phthalate esters (PAEs) in the surface sediments of the mainstream and tributaries of the Songhua River, China, using concentrations and composition of six PAEs, which were analyzed using gas chromatography-mass spectrometery (GC-MS). We assess the ∑PAEs ecological risk using the hazard quotient (HQ) method and environmental risk levels (ERL). The results were as follows.
View Article and Find Full Text PDFFerric-nitrilotriacetate complex (Fe-NTA) has been adopted to catalyze the photo-Fenton degradation of emerging pharmaceutical micropollutants in water and wastewater at neutral pH. The generation of hydroxyl radicals (HO) in UVA/Fe-NTA/HO was identified by using electron spin resonance (ESR) trapping technique. The effects of critical parameters (e.
View Article and Find Full Text PDFInt Forum Allergy Rhinol
November 2018
Background: According to epidemiologic studies, fine particulate matter (particulate matter ≤2.5 μm, PM2.5) is closely associated with increases in the incidence and severity of chronic rhinosinusitis (CRS).
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