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Chiral resolution of binaphthylamine is often a toilful conundrum in the field of analytical chemistry and biomedicine. The work puts forward a selective, sensitive, and miniaturized analytical method based on molecularly imprinted polymers (MIPs) as adsorbent for miniaturized tip solid-phase extraction (MTSPE) in the separation of binaphthylamine enantiomer. This method combines the advantages of MIPs (high selectivity), MTSPE (low consumption), and high-performance liquid chromatography (HPLC, high sensitivity). A simple synthesis methodology of MIP (P2) was conducted through bulk polymerization with (S)-(-)-1,1'-binaphthyl-2,2'-diamine (S-DABN) as template together with methacrylic acid monomer, and ethylene glycol dimethacrylate as cross-linker in proper porogen, realizing a selective recognition and efficient enrichment for S-DABN. The method exhibited appreciable linearity (0.06-1.00 mg ml-1 ), low quantification limit (0.056 mg ml-1 ), good absolute recoveries (45.70%-69.29%), and high precision (relative standard deviations ≤ 3.54%), along with low consumption (0.50 ml sample solution and 25.0 mg adsorbent). Based on the density functional theory, computational simulation was used to make a preliminary prediction for rational design of MIPs and gave a reasonable elaboration involving the potential mechanism of templates interacting with functional monomers. The adsorption kinetics and thermodynamics were investigated to evaluate the recombination process of substrates. In addition, the selectivity of MIPs for S-DABN was obtained by MIP-MTSPE coupled with HPLC, which supports the feasibility of this convenient design process. The proposed method was employed for selective extraction of S-DABN and exhibited promising potential in the application of chiral analysis.
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Impressão Molecular , Polímeros , Adsorção , Cromatografia Líquida de Alta Pressão , Diaminas , Naftalenos , Extração em Fase Sólida , EstereoisomerismoRESUMO
PURPOSE: This network meta-analysis (NMA) is designed to compare the efficacy and tolerability of various therapies and combinations for pulmonary arterial hypertension (PAH). METHOD: We conducted a systematic search in databases PubMed, Embase, and Cochrane Library. Treatment efficacy and tolerability were compared by synthesizing direct and indirect evidence. The surface under the curve ranking area was utilized to rank multiple interventions. RESULT: A total of 43 randomized clinical trials were included in our NMA. With regard to efficacy outcomes, including 6 min walking distance (6MWD), functional class amelioration (FCA), death, clinical worsening (CW), pulmonary vascular resistance (PVR), mean pulmonary artery pressure (mPAP), cardiac index (CI), and mean right atrial pressure (mRAP), endothelin receptor antagonists (ERA), phosphodiesterase 5 inhibitor (PDE-5Is), ERA combined with PDE-5Is (EAP), and prostacyclin analogs (PGI) combined with ERA (PAE) performed better than others. Meanwhile PAP and PGE demonstrated better than others in tolerability. Overall, EAP and PAE showed good efficacy and were well-tolerated among all therapies. CONCLUSION: Overall, we recommend EAP as the optimal choice for patients with PAH in clinical practice and PAE as suboptimal in view of their desirable performance in efficacy. Most of the combination therapies performed better than monotherapies.
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Anti-Hipertensivos/uso terapêutico , Hipertensão Pulmonar/tratamento farmacológico , Humanos , Metanálise em Rede , Artéria Pulmonar/efeitos dos fármacos , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
High salt concentrations can cause plasmolysis and loss of activity of cells, but the salt-tolerant bacterium can endure the high salt concentrations in wastewater. In this research 7 salt-tolerant bacteria, which could survive in dry powder products and could degrade organic contaminants in saline wastewater, were isolated from a membrane bioreactor. The strain NY6 which showed the fastest growth rate, best property for organic matter degradation and could survive in dry powder more than 3 months was selected and characterized. It was classified as Bacillus aerius based on the analysis of the morphological and physiological properties as well as the 16S rRNA sequence and Neigh borjoining tree. The strain NY6 could survive in the salinity up to 6% and the optimal growth salinity is 2%; it belongs to a slightly halophilic bacterium. The capability of its dry powder products for COD removal was 800 mg COD/(g·day) in synthesized saline wastewater with salinity of 2%. According to salt-tolerant mechanism research, when the salinity was below 2%, the stain NY6 absorbed K(+) and Na(+) to maintain osmotic equilibrium, and when the salinity was above 2%, the NY6 kept its life by producing a large amount of spores.
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Bacillus/isolamento & purificação , Bacillus/fisiologia , Reatores Biológicos/microbiologia , Tolerância ao Sal , Membranas Artificiais , Purificação da ÁguaRESUMO
OBJECTIVES: To develop a deep learning (DL) model for segmentation of the suprapatellar capsule (SC) and infrapatellar fat pad (IPFP) based on sagittal proton density-weighted images and to distinguish between three common types of knee synovitis. MATERIALS AND METHODS: This retrospective study included 376 consecutive patients with pathologically confirmed knee synovitis (rheumatoid arthritis, gouty arthritis, and pigmented villonodular synovitis) from two institutions. A semantic segmentation model was trained on manually annotated sagittal proton density-weighted images. The segmentation results of the regions of interest and patients' sex and age were used to classify knee synovitis after feature processing. Classification by the DL method was compared to the classification performed by radiologists. RESULTS: Data of the 376 patients (mean age, 42 ± 15 years; 216 men) were separated into a training set (n = 233), an internal test set (n = 93), and an external test set (n = 50). The automated segmentation model showed good performance (mean accuracy: 0.99 and 0.99 in the internal and external test sets). On the internal test set, the DL model performed better than the senior radiologist (accuracy: 0.86 vs. 0.79; area under the curve [AUC]: 0.83 vs. 0.79). On the external test set, the DL diagnostic model based on automatic segmentation performed as well or better than senior and junior radiologists (accuracy: 0.79 vs. 0.79 vs. 0.73; AUC: 0.76 vs. 0.77 vs. 0.70). CONCLUSION: DL models for segmentation of SC and IPFD can accurately classify knee synovitis and aid radiologic diagnosis.
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Aprendizado Profundo , Sinovite , Masculino , Humanos , Adulto , Pessoa de Meia-Idade , Estudos Retrospectivos , Prótons , Sinovite/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodosRESUMO
Hypoxia and exosomes play important roles in the occurrence and development of glioma. While circRNAs are involved in biological processes of various tumors, the mechanism underlying exosome-dependent regulatory effects of circRNAs on the progression of glioma under hypoxia is unclear. Results suggested that circ101491 was overexpressed in tumor tissues and plasma exosomes of glioma patients, while the overexpression of circ101491 was closely related to the differentiation degree and TNM staging of the patients. Moreover, circ101491 overexpression promoted viability, invasion and migration of glioma cells both in vivo and in vitro; the above regulatory effects can be reversed by inhibition of circ101491 expression. Mechanistic studies revealed that circ101491 upregulated EDN1 expression through sponging miR-125b-5p, thus facilitating glioma progression. In summary, hypoxia could promote circ101491 overexpression in glioma cell-derived exosomes, and circ101491/miR-125b-5p/EDN1 regulatory axis might be implicated in the malignant progression of glioma.
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Endotelina-1 , Glioma , MicroRNAs , Humanos , Linhagem Celular Tumoral , Proliferação de Células , Glioma/metabolismo , Hipóxia , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genética , Endotelina-1/metabolismoRESUMO
A low operating temperature and short response/recovery time are essential factors for sensors. Hence, it is necessary to create a sensor that can quickly detect target gas at a relatively low temperature. In this work, Co3O4 microtube based sensors were fabricated by a bio-template method using absorbent cotton. Co3O4 microtube sensors prepared in different concentrations of a salt solution displayed different sensitivities to triethylamine (TEA). The Co3O4-0.10 microtube sensor exhibited excellent sensitivity to TEA at 160 °C. The response of the Co3O4-0.10 sensor to 100 ppm TEA gas was 31.27 and the detection limit of TEA was 50 ppb. Meanwhile, the Co3O4-0.10 sensor also showed a short response/recovery time, such as 95 s/38 s to 100 ppm TEA, high selectivity, a good linear relationship (R2 = 0.994 for 1-100 ppm TEA and R2 = 0.991 for 50-1000 ppb TEA gas), fine repeatability and long-term stability, and strong humidity resistance. Thus, Co3O4 microtube based sensors prepared using a bio-template method have potential application prospects for the detection of TEA gas.
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Polyvinylchloride (PVC) ultrafiltration membranes were modified by blending with single-walled carbon nanotubes (SWCNTs) to improve the membranes' antibacterial property. Both modified and control samples were characterized for pore structure, roughness, hydrophilicity, permeability and mechanical properties. The membranes' antibacterial property was accessed with Escherichia coli as the model microbes by several methods. It was found that, after being blended with SWCNTs, the surface roughness of the modified membrane increased. Also, the surface hydrophilicity was improved. The membrane flux increased accordingly. But the membrane elongation decreased obviously with the SWCNTs addition. The modified membranes did not show the antibacterial property as expected in this research. There was no bacterial inhibition circle around the SWCNTs/PVC membrane coupons in the culture plates. There were no morphological differences of the cells on the control and the modified membranes. Hoechst 33342/propidium iodide stain test showed that there were more than 90% living bacterial cells which could grow on the SWCNTs/PVC membranes. This study suggests that the polymer wrapping may reduce the SWCNTs' antibacterial property greatly.
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Antibacterianos , Membranas Artificiais , Nanotubos de Carbono , Cloreto de Polivinila , Benzimidazóis , Contagem de Colônia Microbiana , Escherichia coli/crescimento & desenvolvimentoRESUMO
Magnetic spinel ferrite (CuFe2O4) has been applied to catalyze ozone for treating the practical shale gas produced water (PW) in our previous study. In this work, CuFe2O4/titanium nanotubes (TNTs) catalyst was successfully prepared by an impregnation-calcination method. Characterization results revealed that the crystal form of CuFe2O4 was bound to the surface of TNTs, the particle size is much smaller than the pure CuFe2O4 crystal particle, which could weaken the influence of the internal diffusion process on its catalytic efficiency. The experimental results showed that the removal ratio of CODCr in the CuFe2O4/TNTs/O3 system was approximately 14% higher than that of the CuFe2O4/O3 system. The dissolution of metal elements decreased to one-third that of the CuFe2O4/O3 system. The inhibition ratio of PW on the growth of E. coli K12 decreased 68% after the CuFe2O4/TNTs catalytic oxidation process. Experimental results of complete capture experiments illustrated that the yield of HO⢠of the CuFe2O4/TNTs/O3 system was 10-19% higher than that of the CuFe2O4/O3 system. The elemental valence analysis revealed that the transition of Cu(II)-Cu(III) and Fe(II)-Fe(III) coexisted in the catalytic system. Besides, the surface hydroxyl groups promoted the electron transfer process and enhanced the ozone adsorption affinity. The proposed catalytic mechanisms of the CuFe2O4/TNTs/O3 system were proposed via the above analysis.
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Nanotubos , Ozônio , Poluentes Químicos da Água , Catálise , Escherichia coli , Compostos Férricos , Fenômenos Magnéticos , Gás Natural , Titânio , ÁguaRESUMO
It is extremely necessary to detect Hydrogen sulfide (H2S) due to the hazardous nature. Thus, it is required to design a material which can detect H2S gas at low temperature. In this work, ZnCo2O4 microtubes are prepared by using absorbent cotton as template, combining immersion method in metal salt solution (Zn:Co=1:2) with calcination treatment in air. The influence of calcination temperature on the particle size and sensing property was also discussed. The diameter of particles on the ZnCo2O4 microtubes increases with increasing calcination temperature. The hollow microtubes of ZnCo2O4 materials calcined at 600 °C (ZCO-600) exhibit superb sensing performance to H2S at 90 °C with the lowest detection limit of 50 ppb. The optimum operating temperature (90 °C) was lower than the other reported ZnCo2O4 sensors. ZCO-600 sensor also shows excellent selectivity, repeatability, stability, humidity resistance and the good linear relationship in ppb and ppm level H2S. In addition, the feasible sensing mechanism of ZCO-600 to H2S is explored on the basis of XPS analysis. Thus, ZnCo2O4 as a sensing material possesses widespread application prospects for the detection of trace H2S gas.
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Uranium (U) is hazardous and radioactive, wastewater containing U(VI) should be treated before being discharged. Here, two novel uranium adsorbents, phosphorylated hyper-cross-linked bisphenol A (PHCP-1) and fluorene-9-bisphenol (PHCP-2) were separately synthesized via Friedel-Crafts reaction followed by phosphorylation using phosphorus oxychloride. PHCPs had a BET surface area (up to 564 m2/g) with pore sizes of 2.2-2.8 nm. These adsorbents were used for the first time for uranium adsorption from water and demonstrated outstanding adsorption performance. PHCP-2 had a great uranium adsorption capacity (297.14 mg/g) and a very fast sorption rate (85% removal rate within 5 min). The adsorption data were well fitted with Freundlich isotherm and the pseudo-second-order kinetic model. PHCPs displayed selective adsorption capacity for U(VI) from solution that including a variety of competing metal ions. The reusability was confirmed through three regeneration cycles. Based on a series of spectroscopic analyses, the mechanism of action between PHCPs and U(VI) is primarily derived from the complex between phosphate functional groups and U (VI). The sorption performance of PHCPs is attributed to their huge specific surface area and the strong complex between phosphate groups and U(VI). These findings suggest that PHCPs could be useful in the effective adsorption of uranium from water.
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Urânio , Adsorção , Compostos Benzidrílicos , Concentração de Íons de Hidrogênio , Cinética , Fenóis , Polímeros , Urânio/análise , ÁguaRESUMO
At present, membrane fouling is a thorny issue that limits the development of polyvinylidene fluoride (PVDF) composite membrane, which seriously affects its separation performance and service lifespan. Herein, an imidazole-functionalized graphene oxide (Im-GO) with hydrophilicity and antibacterial performance was synthesized, and it was used as a modifier to improve the anti-organic fouling and antibacterial properties of PVDF membrane. The anti-organic fouling test showed that the maximum flux recovery ratios against bovine serum albumin and humic acid were 88.9% and 94.5%, respectively. Conspicuously, the grafted imidazole groups could effectively prevent the bacteria from growing on the membrane surface. It was gratifying that the antibacterial modifier Im-GO was almost not lost from the hybrid membranes even by the ultrasonic treatment, which was different from the conventional release-killing antibacterial agents. Owing to the long-term anti-organic fouling and antibacterial properties, Im-GO/PVDF hybrid membranes exhibit a great application potential in the fields of rough separation and concentration of biomedical products.
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Membranas Artificiais , Ultrafiltração , Antibacterianos/farmacologia , Polímeros de Fluorcarboneto , Grafite , Imidazóis/farmacologia , Polivinil/farmacologiaRESUMO
The phenomenon of nontraditional luminescence has attracted wide attention and curiosity of researchers due to its inexplicable photoluminescence paradigm without aromatic or extended π-systems. The present work puts forward a neotype of a light-emitting nitrogenous small molecule, namely, N-stearoyl-hydroxyproline (L-C16-Hyp), which could emit weak light in aggregation states through the restriction mechanism of intramolecular motion, exhibiting properties comparable to those of AIEgens. Using these molecular aggregates as anionic surfactant micelles to incorporate within the silica matrix, we prepared fluorescent nanoparticles (FL-NPs) by a one-pot method for expedient visualization of latent fingerprints (LFPs). The FL-NPs exhibit an excitation range from 335 to 365 nm, resulting in nontraditional luminescence observed between 410 and 440 nm. The enhanced luminescent FL-NPs may derive from the collective entities or assemblies of restricted L-C16-Hyp, which can be reasonably explicated by an effect termed as cluster-triggered emission (CTE). Theoretical calculations demonstrated that this luminescence pattern belongs to partial charge transfer, which is mainly attributed to the close interaction between the tertiary amino and adjacent carboxyl in the L-C16-Hyp structure. Moreover, some merits of FL-NPs, such as wormlike nanomorphology, stable photophysical properties, low toxicity, great adhesion to multiple substrates, easy to get raw material, an inexpensive, simple process, and rapid detection without any further modification or assistance, provide the feasibility of efficacious LFP detection. Overall, this study will provide insights into the design and application of luminescent materials with unconventional groups.
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In order to improve the anti-biofouling performance of ultrafiltration membrane, quaternized graphene oxide (QGO) was synthesized as a membrane modifier by in-situ growth of quaternary ammonium salt on the graphene oxide surface. A hydrophilic and antibacterial dual functional membrane was prepared with this kind of modifiers by immersion phase inversion method. The modified membrane obviously exhibits enhanced hydrophilicity, antibacterial and mechanical properties than the unmodified Polyvinylidene fluoride (PVDF) membranes. At the same time, it is proved that graphene oxide, as a carrier of quaternary ammonium salt, can significantly reduce the loss of antibacterial substances from the membranes.
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Antibacterianos/química , Grafite/química , Membranas Artificiais , Polivinil/química , Interações Hidrofóbicas e Hidrofílicas , UltrafiltraçãoRESUMO
AIMS: Ubiquitination of proteins meant for elimination is a primary method of eukaryotic cellular protein degradation. The ubiquitin carrier protein E2-EPF is a key degradation enzyme that is highly expressed in many tumors. However, its expression and prognostic significance in brain glioma are still unclear. The aim of this study was to reveal how the level of E2-EPF relates to prognosis in brain glioma. METHODS: Thirty low-grade and 30 high-grade brain glioma samples were divided into two tissue microarrays each. Levels of E2-EPF protein were examined by immunohistochemistry and immunofluorescence. Quantitative real-time polymerase chain reaction was used to analyze the level of E2-EPF in 60 glioma and 3 normal brain tissue samples. The relationship between E2-EPF levels and prognosis was analyzed by Kaplan-Meier survival curves. RESULTS: E2-EPF levels were low in normal brain tissue samples but high in glioma nuclei. E2-EPF levels gradually increased as glioma grade increased (p < 0.05). Ectopic E2-EPF levels in high-grade glioma were significantly higher than in low-grade glioma (p < 0.01). The 5-year survival rate of glioma patients with high E2-EPF levels was shorter than in patients with low expression (p < 0.05). Furthermore, the 5-year survival rate of patients with ectopic E2-EPF was significantly shorter than patients with only nuclear E2-EPF (p < 0.01). CONCLUSIONS: These results suggest that higher E2-EPF levels, especially ectopic, are associated with higher grade glioma and shorter survival. E2-EPF levels may play a key role in predicting the prognosis for patients with brain glioma.
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Enzimas de Conjugação de Ubiquitina/genética , Enzimas de Conjugação de Ubiquitina/metabolismo , Adolescente , Adulto , Biomarcadores Tumorais/metabolismo , Encéfalo/patologia , Neoplasias Encefálicas/genética , Criança , Pré-Escolar , China , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Glioma/genética , Humanos , Lactente , Recém-Nascido , Estimativa de Kaplan-Meier , Masculino , Prognóstico , Taxa de Sobrevida , Ubiquitinação/genética , Adulto JovemRESUMO
Three sequencing batch reactors supplied with different carbon sources were investigated. The system supplied with glucose gained the best enhanced biological phosphorus removal although all of the three reactors were seeded from the same sludge. With the measurement of poly-beta-hydroxyalkanoate (PHA) concentration, phosphorus content in sludge and extracellular exopolymers (EPS) with scanning electron microscopy (SEM) combined with energy dispersive spectrometry (EDS), it was found that the biosorption effect of EPS played an important role in phosphorus removal and that the amount of PHA at the end of anaerobic phase was not the only key factor to determine the following phosphorus removal efficiency.
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Fósforo/química , Polissacarídeos Bacterianos/química , Esgotos/química , Esgotos/microbiologia , Eliminação de Resíduos Líquidos/métodos , Adsorção , Bactérias/metabolismo , Biodegradação Ambiental , Biopolímeros/química , Reatores Biológicos , Espectrometria de Massas , Microscopia Eletrônica de Varredura , Fósforo/análise , Fósforo/metabolismoRESUMO
By a membrane bioreactor with a settle tank in long-term operation and batch experiments, the effects of flocs, soluble microorganism products (SMPs) and metal ions in activated sludge liquor on membrane fouling were investigated. The results showed that foulants absorbed each other and formed a fouling layer as a "second membrane" influencing the permeability of the membrane. The "gel layer" caused by SMPs and "cake layer" by flocs showed great differences in morphology by analysis of scanning electron microscope and atomic force microscope. The "gel layer" was more compact and of poor permeability. When the membrane flux was 40 L/(m(2) x h), the rate of membrane fouling caused by supernatant (0.011 MPa/h) was greater than that by sludge liquor (0.0063 MPa/h). SMPs played very important roles on membrane fouling. In the bulking sludge, with SMPs increasing, the rate of membrane fouling (0.0132 MPa/h) was faster. While after flocculation of the SMPs, the rate of fouling decreased to 0.0034 MPa/h. Flocs could keep holes in their overlaps. They could alleviate membrane fouling by preventing the SMPs directly attaching on membrane surface.
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Reatores Biológicos , Membranas Artificiais , Esgotos , Filtração , Microscopia Eletrônica de Varredura , Peso MolecularRESUMO
To improve the anti-biofouling properties of PVDF membranes, GO-Ag composites were synthesized and used as membrane antibacterial agent by a simple and environmentally friendly method. As identified by XRD, TEM and FTIR analysis, AgNPs were uniformly assembled on the synthesized GO-Ag sheets. The membranes were prepared by phase inversion method with different additional amounts (0.00-0.15wt%) of GO-Ag composites. The GO-Ag composites modified membranes show improved hydrophilicity, mechanical property and permeability than unmodified PVDF membrane. Specially, the antibacterial properties and inhibition of biofilm formation were greatly enhanced based on conventional inhibition zone test and anti-adhesion of bacterial experiment. The modified membranes also reveal a remarkable long-term continuous antimicrobial activity with slower release rate of Ag+ compared to AgNPs/PVDF membrane.
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Antibacterianos/farmacologia , Grafite/química , Membranas Artificiais , Nanopartículas Metálicas/química , Polivinil/química , Prata/farmacologia , Antibacterianos/química , Aderência Bacteriana/efeitos dos fármacos , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Química Verde , Interações Hidrofóbicas e Hidrofílicas , Nanopartículas Metálicas/ultraestrutura , Óxidos , Transição de Fase , Prata/química , Ultrafiltração/instrumentaçãoRESUMO
A novel polyvinyl chloride (PVC) membrane was modified with graphene oxide (GO) via phase inversion method to improve its hydrophilicity and mechanical properties. The GO presented a large amount of hydrophilic groups after the modification through the modified Hummers method. It was observed that with the addition of low fraction of GO powder, the GO/PVC hybrid membranes exhibited a significant enhancement in hydrophilicity, water flux, and mechanical properties. With optimal dosage (0.1wt%), the pure water flux of GO/PVC membrane increased from 232.6L/(m(2)hbar) to 430.0L/(m(2)hbar) and the tensile strength increased from 231.3cN to 305.3cN. The improved properties of the PVC/GO hybrid membranes are mainly attributed to the strong hydrophilicity of functional groups on the GO surface, indicating that GO has a promising candidate for modification of PVC ultrafiltration membranes in wastewater treatment.
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The performance and microbial community profiles in a sequencing batch reactor (SBR) treating saline wastewater were studied over 300days from 0wt% to 3.0wt% salinity. The experimental results indicated that the activated sludge had high sensitivity to salinity variations in terms of pollutants removal and sedimentation. At 2.0wt% salinity, the system retained a good performance, and 95% removal rate of chemical oxygen demand (COD), biochemical oxygen demand (BOD), NH4(+)-N and total phosphorus (TP) could be achieved. Operation before addition salinity revealed the optimal performance and the most microbial diversity indicated by 16S rRNA gene clone library. Sequence analyses illustrated that Candidate_division_TM7 (TM7) was predominant at 2.0 wt% salinity; however, Actinobacteria was more abundant at 3.0wt% salinity.
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Reatores Biológicos/microbiologia , Salinidade , Esgotos/microbiologia , Purificação da Água/métodos , Análise da Demanda Biológica de OxigênioRESUMO
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