A novel process for nutrients removal and phosphorus recovery from domestic wastewater by combining BNR with induced crystallization

An excessive discharge of phosphorus from wastewater to water bodies may potentially contribute to eutrophication. On the other hand, mineral phosphorus resources will be depleted in the near future, because of difficulty to automatically recycle from water to land, unlike nitrogen. A new process for nutrients removal coupled with phosphorus recovery was proposed in this study by combining biological nutrients removal (BNR) with induced crystallization (IC), BNR-IC for short later, differently from conventional phosphorus recovery process. Our results showed that the BNR-IC system can maintain not only high and stable carbon, nitrogen and phosphorus removal efficiencies, all presenting above 90%, but also good phosphorus recovery performance from synthetic domestic wastewater, displaying about 70.2% of phosphorus recovery rate. When the COD, TN, NH4–N and P concentrations of 250 mg L−1, 42 mg L−1, 40 mg L−1, and 10 mg L−1, respectively were given in the influent, a stable removal efficiencies of 92.5% COD, 78.6% TN, 85.9% NH4–N and 95.2% P were obtained for the BNR-IC process and correspondingly the COD, TN, NH4–N and P concentrations of 18.75 mg L−1, 8.99 mg L−1, 5.64 mg L−1, 0.42 mg L−1 were monitored in the effluent, meeting the Chinese National Class I (grade A) Sewage Discharge Standard. Analyses of SEM and EDS, moreover, also demonstrated that the surface of seed crystal (calcite used here) was completely covered by hydroxyl calcium phosphate (HAP) produced during the induced crystallization process to recover phosphorus. Although our study involved only a small-scale trial, the proposed BNR-IC process here may be a promising technology, and can potentially aid in improvement of the effluent quality from WWTP and in recycle of mineral phosphorus resources when applied to practice

An innovative continuous flow BNR-IC process for nutrients removal and phosphorus recovery from synthetic and real domestic wastewater

An innovative continuous flow process linking biological nutrients removal (BNR) with induced crystallization (IC) was used to remove nutrients and recover phosphorus (P) from synthetic and real domestic wastewater. The results showed that a good nutrients removal performance was found regardless of feeding solutions. P recovery efficiency from synthetic wastewater was 70.2% slightly less than that from real domestic sewage (74.2%). Importantly, P recovery can effectively enhance the subsequent biological P removal. Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analysis displayed an obvious shift in microbial community structure when switching feeding synthetic solution to real wastewater. A total of 13 bands were detected in sludge samples using synthetic and real domestic sewage, affiliated with 8 phyla or classes domain Bacteria (Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Flavobacteria, Actinobacteria, Sphingobacteria, Epsilonproteobacteria and Chlorobia). The results obtained here suggest that the continuous flow BNR-IC process is feasible for nutrients removal and P recovery from domestic sewage and is a promising technology for wastewater treatment combined with recycling of P elements

Effects of Black Pepper (Piper nigrum L.)

The chemical composition and antimicrobial mechanism of action of black pepper chloroform extract (BPCE) were investigated, as well as the potential antibacterial activities of BPCE against Escherichia coli and Staphylococcus aureus. The results showed that 1H-Cycloprop[e]azulen-7-ol, decahydro-1,1,7-trimethyl-4-methylene-, [1ar-(1aα,4aα,7β,7a,β,7bα.)]- (8.39%) and 2-methylene-4,8,8-trimethyl-4-vinyl-bicyclo[5.2.0]nonane (6.92%) were identified as the two primary components of BPCE. The release of intracellular transaminases from bacteria after being incubated with BPCE revealed that the bacterial cell walls and membranes were degraded and that protein synthesis was inhibited to some extent. The inhibition of bacterial Na+/K+-ATPase activity upon the addition of BPCE also indicated an enhanced permeability of bacterial cell membranes. Moreover, an analysis of hexokinase and pyruvate kinase activities showed that BPCE affected the metabolic rate of glycolysis and disrupted the normal metabolism of bacteria. This phenomenon was supported by an observed accumulation of lactic acid (LA) in the treated bacterial cells. Overall, our results indicated that BPCE damaged bacterial cell walls and membranes, which was followed by a disruption of bacterial cell respiration

m6A demethylase FTO and osteoporosis: potential therapeutic interventions

Osteoporosis is a common bone disease, characterized by a descent in bone mass due to the dysregulation of bone homeostasis. Although different studies have identified an association between osteoporosis and epigenetic alterations in osteogenic genes, the mechanisms of osteoporosis remain unclear. N6-methyladenosine (m6A) modification is a methylated adenosine nucleotide, which regulates the translocation, exporting, translation, and decay of RNA. FTO is the first identified m6A demethylase, which eliminates m6A modifications from RNAs. Variation in FTO disturbs m6A methylation in RNAs to regulate cell proliferation, differentiation, and apoptosis. Besides, FTO as an obesity-associated gene, also affects osteogenesis by regulating adipogenesis. Pharmacological inhibition of FTO markedly altered bone mass, bone mineral density and the distribution of adipose tissue. Small molecules which modulate FTO function are potentially novel remedies to the treatment of osteoporosis by adjusting the m6A levels. This article reviews the roles of m6A demethylase FTO in regulating bone metabolism and osteoporosis

Silicon Layer Intercalation of Centimeter-Scale, Epitaxially-Grown Monolayer Graphene on Ru(0001)

We develop a strategy for graphene growth on Ru(0001) followed by silicon-layer intercalation that not only weakens the interaction of graphene with the metal substrate but also retains its superlative properties. This G/Si/Ru architecture, produced by silicon-layer intercalation approach (SIA), was characterized by scanning tunneling microscopy/spectroscopy and angle resolved electron photoemission spectroscopy. These experiments show high structural and electronic qualities of this new composite. The SIA allows for an atomic control of the distance between the graphene and the metal substrate that can be used as a top gate. Our results show potential for the next generation of graphene-based materials with tailored properties.Comment: 13 pages, 4 figures, to be published in Appl. Phys. Let

Measurements of the Cross Section for e+e- -> hadrons at Center-of-Mass Energies from 2 to 5 GeV

We report values of $R = \sigma(e^+e^-\to {hadrons})/\sigma(e^+e^-\to\mu^+\mu^-)$ for 85 center-of-mass energies between 2 and 5 GeV measured with the upgraded Beijing Spectrometer at the Beijing Electron-Positron Collider.Comment: 5 pages, 3 figure

COSORE: A community database for continuous soil respiration and other soil‐atmosphere greenhouse gas flux data

Globally, soils store two to three times as much carbon as currently resides in the atmosphere, and it is critical to understand how soil greenhouse gas (GHG) emissions and uptake will respond to ongoing climate change. In particular, the soil‐to‐atmosphere CO2 flux, commonly though imprecisely termed soil respiration (RS), is one of the largest carbon fluxes in the Earth system. An increasing number of high‐frequency RS measurements (typically, from an automated system with hourly sampling) have been made over the last two decades; an increasing number of methane measurements are being made with such systems as well. Such high frequency data are an invaluable resource for understanding GHG fluxes, but lack a central database or repository. Here we describe the lightweight, open‐source COSORE (COntinuous SOil REspiration) database and software, that focuses on automated, continuous and long‐term GHG flux datasets, and is intended to serve as a community resource for earth sciences, climate change syntheses and model evaluation. Contributed datasets are mapped to a single, consistent standard, with metadata on contributors, geographic location, measurement conditions and ancillary data. The design emphasizes the importance of reproducibility, scientific transparency and open access to data. While being oriented towards continuously measured RS, the database design accommodates other soil‐atmosphere measurements (e.g. ecosystem respiration, chamber‐measured net ecosystem exchange, methane fluxes) as well as experimental treatments (heterotrophic only, etc.). We give brief examples of the types of analyses possible using this new community resource and describe its accompanying R software package

Optimization of induced crystallization reaction in a novel process of nutrients removal coupled with phosphorus recovery from domestic wastewater

Phosphorus removal and recovery from domestic wastewater is urgent nowadays. A novel process of nutrients removal coupled with phosphorus recovery from domestic sewage was proposed and optimization of induced crystallization reaction was performed in this study. The results showed that 92.3% of phosphorus recovery via induced Hydroxyapatite crystallization was achieved at the optimum process parameters: reaction time of 80 min, seed crystal loads of 60 g/L, pH of 8.5, Ca/P mole ratio of 2.0 and 4.0 L/min aeration rate when the PO43--P concentration was 10 mg/L in the influent, displaying an excellent phosphorus recovery performance. Importantly, it was found that the effect of reaction temperature on induced Hydroxyapatite crystallization was slight, thus favoring practical application of phosphorus recovery method described in this study. From these results, the proposed method of induced HAP crystallization to recover phosphorus combined with nutrients removal can be an economical and effective technology, probably favoring the water pollution control and phosphate rock recycle

Evaluation of integrated UFCW-MFC reactor for azo dye wastewater treatment and simultaneous bioelectricity generation

An up-flow constructed wetland (UFCW) incorporating a novel membrane-less air-cathode single-chamber microbial fuel cell (MFC) was designed to treat dye wastewater and simultaneously generate bioelectricity. The performance of UFCW-MFC was evaluated via Methyl Orange (MO) and chemical oxygen demand (COD) removal rates and the output voltage. For comparison, the performance of a single UFCW was also assessed. A repeatable and stable voltage output of about 0.44±0.2 V was obtained in UFCW-MFC. The MO and COD removal rates in UFCW-MFC were 93.5 and 57.2%, respectively, significantly higher than those in single UFCW (75.4 and 42.6%, respectively), suggesting the obvious enhancement of electrodes on MO and COD removal. The anode zone of UFCW-MFC made the most contribution to MO and COD removal compared with other layers. The oxidation-reduction potential (ORP) and dissolved oxygen (DO) profiles showed that the anaerobic environment was well developed in the lower part of UFCW-MFC (0–24 cm) and the upper part (41–42 cm) had a good aerobic environment, thus greatly contributing to the MO anaerobic reduction and aerobic degradation of breakdown products. These results obtained here suggest that the UFCW-MFC may provide an effective alternative for the treatment of dye wastewater and simultaneous bioelectricity generation