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1.
Chemosphere ; 274: 129783, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33545591

RESUMO

In this study, nano-sized CoFe2O4 composites were prepared through co-precipitation process. Then the phosphorus-doped strong magnetic graphitic carbon nitride hybrids composites (P-CoFe2O4@GCN) was stemmed from the CoFe2O4 composites via the thermal polymerization method. The TEM results show that the CoFe2O4 nanoparticles have been successfully embedded into the graphitic carbon nitride (GCN). The BET specific surface area of P-CoFe2O4@GCN-1 could reach 36.91 m2/g, which was 5.38 times higher than that of GCN. Thus, it provided sufficient reaction active sites to enhance the photocatalytic activity for tetracycline (TC) decomposition. The results from the photocatalytic experiments showed that the degradation efficiency of TC by P-CoFe2O4@GCN-1 could reach 96.2% within 60 min, which is 3.19 times higher than that of GCN. The h+, O2•- and •OH radicals detected by the electron spin resonance (ESR) were responsible for the TC decomposition in the photocatalytic reaction system. Persulfate (PS) can further activate the hybrid mixture system, and the fitting model predicted by the response surface methodology (RSM) indicated that the maximum tetracycline removal could reach 99.6% within 30 min. In addition, the degradation intermediates of TC were detected by HPLC-MS and the photodegradation mechanism was discussed.

2.
J Hazard Mater ; 401: 123374, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-32653792

RESUMO

In this work, novel NiSiO@NiAlFe layered double hydroxides (LDHs) hollow spheres were prepared by hydrothermal method. It was worth noting that LDHs' grafting towards NiSiO hollow spheres could avoid the LDHs' aggregation, and thus enhanced the material's adsorption capacity. Furthermore, adsorption kinetics, adsorption isotherms, and Box-Behnken Design (BBD) model were conducted. Results indicated that NiSiO@NiAlFe LDHs hollow spheres had sufficient adsorption capability towards Cs+. The adsorption kinetics satisfied the pseudo-second-order adsorption model, Temkin model and Langmuir isotherm model. The adsorption process was efficient at the alkaline condition (pH = 10). The adsorption kinetics indicated that the adsorption process could reach the equilibrium in only 20 min. The maximum adsorption capacity of Cs+ towards NiSiO@NiAlFe LDHs hollow spheres was estimated to be 61.5 mg g-1. Moreover, the adsorption thermodynamics indicated that the adsorption process was exothermal, feasible and spontaneous. Thus, NiSiO@NiAlFe LDHs hollow spheres presented a broad potential for treating cesium containing wastewater.

3.
Chemosphere ; 262: 127832, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32758709

RESUMO

This article has been retracted: please see Elsevier Policy on Article Withdrawal ( https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Authors. The corresponding author informed the journal that there were severe problems with the testing instrument that rendered the subsequent conclusions invalid. The authors apologise for any inconvenience caused.

4.
Chemosphere ; : 128806, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33187647

RESUMO

In this study, novel core-shell catalyst with a new ternary heterostructure was synthesized (Fe0@POCN/CQDs) for the degradation of tetracycline (TC). The TEM results showed that the Fe0 particles were wrapped in POCN material and many nano CQDs were uniformly dispersed in the material. The new ternary nanocomposite exhibits excellent photocatalytic activity for the removal of TC, which was approximately 4.76 times higher than that of GCN. The enhancement of photocatalytic activity was attributed to the effective heterojunction as well as the multiply synergistic effects of POCN combined with Fe0 and CQDs, which was beneficial for retardation of recombination rate of photogenerated electron-hole pairs and generation of more free radicals for the oxidation of TC. Besides, the reactive oxygen species (ROS) of h+, •O2- and •OH played pivotal roles in the degradation of TC by Fe0@POCN/CQDs during the photocatalytic reaction. At the same times, sulfate radical (SO4•-) and hydroxyl radical (•OH) highlighted the dominant role in the degradation process compared with other free radicals under persulfate hybrid mixture system (PS system), which was further confirmed by radical scavenger experiments and electron spin resonance (ESR) analysis. The response surface methodology (RSM) study indicated that the optimal removal parameters of tetracycline could reach 97.57% within 30 min under PS system. In addition, the possible degradation pathway intermediates of TC were studied by HPLC-MS and the reaction catalytic activity mechanism of Fe0@POCN/CQDs/persulfate system was discussed.

5.
PLoS One ; 15(10): e0240311, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33104738

RESUMO

BACKGROUND AND AIMS: Purchasing Chinese herbal medicine (CHM) without a physician's prescription may have adverse effects on health. However, the recent status of purchasing non-prescribed CHM and the associated factors are not completely understood. We aimed to report the prevalence of purchasing CHM and associated factors. METHODS: Using data from the 2017 Taiwan Survey of Family Income and Expenditure, we identified 16,528 individuals (householders) aged 18 years and older. Sociodemographic factors, expenditures on medical services and health behaviours were compared between people with and without a history of purchasing non-prescribed CHM by calculating adjusted odds ratios (ORs) and 95% confidence intervals (CIs) in a multiple logistic regression analysis. RESULTS: The one-year prevalence of purchasing non-prescribed CHM was 74.8% in Taiwan. In addition to sociodemographics, marital status (OR 2.14, 95% CI 1.88-2.44), the use of traditional Chinese medicine (OR 3.62, 95% CI 3.30-3.97), the purchasing of non-prescribed biochemical medications (OR 3.09, 95% CI 2.75-3.48), the purchasing of health foods (OR 2.59, 95% CI 2.33-2.86), the use of folk therapy (OR 2.27, 95% CI 1.95-2.64), and a high level of expenditure on alcohol (OR 3.79, 95% CI 3.29-4.36) were strongly correlated with purchasing non-prescribed CHM. CONCLUSION: The one-year prevalence of purchasing non-prescribed CHM is very high in Taiwan and is correlated with sociodemographics, health behaviours, and the utilization of medical care. The interaction of non-prescribed CHM with physician-prescribed herbal medicine and biomedical medications requires more attention.

6.
Chemosphere ; 264(Pt 1): 128410, 2020 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-33002803

RESUMO

Community-intrinsic properties affect the composition and function of a microbial community. Understanding the microbial community-intrinsic properties in drinking water distribution systems (DWDS) could help to select disinfection strategies and aid in the prevention of waterborne infectious diseases. In this study, we investigated the formation of multi-species biofilms in six groups, each consisting of four or five mixed bacterial strains isolated from a simulated DWDS, at different incubation times (24, 48, and 72 h). We then evaluated the chlorine resistance of the 72-h multi-species biofilms in the presence of 0.3, 0.6, 1, 2, 4, and 10 mg/L residual chlorine. Microbacterium laevaniformans inhibited the formation of multi-species biofilms, Sphingomonas sp., Acinetobacter sp. and A. deluvii had the effect of promoting their growth, and B. cereus has little effect on the growth of multi-species biofilms. However, these inhibition and promotion effects were weak and inadequate to completely control the growth of multi-species biofilms. All multi-species produced strong biofilms after 72 h incubation, which could be due to microbial community-intrinsic properties. Community-intrinsic properties could maintain high EPS production and cell-to-cell connections in multi-species biofilms, and could affect the formation of multi-species biofilms. The chlorine resistance of multi-species biofilms was significantly improved by B. cereus, but significantly reduced by M. laevaniformans. These results indicated that the microbial community-intrinsic properties were influenced by the environment. At a relatively low disinfectant concentration (<2 mg/L residual chlorine), the community-intrinsic properties were maintained; however, when the disinfectant concentration was increased to 2-4 mg/L residual chlorine, the community-intrinsic properties weakened, and significantly affected the resistance of the microbial communities to the disinfectant. With further increases in concentration, to >4 mg/L residual chlorine, no significant difference was observed in the disinfectant resistance of the microbial community.

7.
Environ Sci Pollut Res Int ; 27(31): 39198-39210, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32638312

RESUMO

In this work, hierarchical structure TiO2/hemp stem biochar carbon (HSBC) and C3N4-TiO2/HSBC were successfully fabricated, which were used as efficient visible-light photocatalyst degradation for ammonia nitrogen from aqueous solution. The as-prepared C3N4-TiO2/HSBC hybrid catalyst showed the higher efficient photocatalytic activity for decomposition of ammonia nitrogen than those of pure TiO2 and TiO2/HSBC, suggesting suppressed recombination of photogenerated charges and promoted mass transfer due to synergistic effect, and thus increased photocatalytic degradation activity. The degradation of ammonia follows a pseudo-first-order kinetics. All prepared catalysts demonstrated extremely photocatalytic efficiency under visible-light and UV light illumination; the ammonia nitrogen photocatalytic degradation activity of C3N4-TiO2/HSBC can reach 90.3% under UV light while the degradation activity achieved about 50.7% under visible-light irradiation. The results revealed that the h+ was dominantly active intermediates in the process of photocatalytic degradation. The prepared catalysts are promising for the degradation of ammonia nitrogen from water resource.


Assuntos
Cannabis , Carvão Vegetal , Nitrilos , Titânio
8.
Bioresour Technol ; 308: 123272, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32276202

RESUMO

Oilseed rape straw (ORS) is capable of producing renewable energy. However, cellulose, hemicellulose and lignin are intertwined together in ORS, which makes it difficult for anaerobic digestion (AD). Hence, pretreatment is the key factor in reducing the rate-limiting step of AD. This study reports that the pretreatment combined fermentation broth and micro-oxygen could enhance the degradation of ORS. The maximum biodegradation ratios of cellulose, hemicellulose, and lignin (CHL) were 20.6%, 18.1%, and 24.7%, respectively, at 120 mL/gVS/d oxygen load. The maximum volatile fatty acids and soluble chemical oxygen demand of hydrolysis and acidification of the pretreated groups were significantly higher than that of the control groups. Microorganisms in the fermentation broth at micro-aerobic conditions led to the reduction of CHL content, and altered the structure of ORS. The fermentation broth bio-pretreatment could effectively decrease the functional groups related to lignin.


Assuntos
Lignina , Oxigênio , Fermentação , Concentração de Íons de Hidrogênio , Hidrólise
9.
J Environ Manage ; 263: 110377, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32174524

RESUMO

Because of its superior physical and chemical properties, MnFe2O4 is regarded as one of the best magnetic material alternatives for Fe3O4. However, MnFe2O4 alone cannot remove heavy metal ions and dyes. Here, we report on a new mesoporous magnetic MnFe2O4@CS-SiO2 microsphere material that was synthesised via the hydrothermal method to remove Zn2+ and methylene blue (MB) in simulated textile wastewater. The composite was characterised using a vibrating sample magnetometer, scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy, X-ray powder diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and a Brunauer-Emmett Teller analysis. The pH, adsorbent dosage, initial adsorbate concentration, and reaction time effects on the removal of Zn2+ and MB were studied under different conditions, and a possible removal mechanism was proposed and discussed. The experimental results show that the suitable pH range for MB adsorption was extremely wide, and the adsorption equilibrium can be reached within 30 min. In addition, the prepared material has excellent stability. With an excellent removal efficiency as high as 56.1% and 93.86% for Zn2+ and MB, respectively, after five consecutive cycles and a superior adsorption capacity compared with other materials, the prepared composite in this paper proved to be a promising and effective magnetic adsorbent for the removal of Zn2+ and MB from textile wastewater.


Assuntos
Azul de Metileno , Poluentes Químicos da Água , Adsorção , Fenômenos Magnéticos , Microesferas , Dióxido de Silício , Zinco
10.
Environ Sci Pollut Res Int ; 27(13): 15337-15349, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32077017

RESUMO

A novel catalyst of Fe-Mn/AC was prepared and used as a heterogeneous catalyst to activate O3/Na2S2O8 for landfill leachate biochemical effluent treatment. The experimental results indicated that the highest COD (84%) and color (98%) removal was obtained at Fe-Mn/AC dosage 1.2 g/L, O3 concentration 1.2 g/L, Na2S2O8 dosage 6 g/L, initial pH 10, and reaction time 100 min. Three-dimensional and excitation emission matrix (3D-EEM) fluorescence spectrometry, Fourier transform infrared spectroscopy (FTIR), and gas chromatography mass spectrometry (GC/MS) of wastewater samples before and after treatment demonstrated that the leachate biochemical effluent contained a large amount of humic and fulvic acid organic compounds. After treatment with this coupling system, both the pollution level of dissolved organic matter (DOM) and the fluorescence intensity declined. The micro morphology of Fe-Mn/AC was characterized using scanning X-ray diffraction patterns (XRD), electron microscope spectra (SEM), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared (FTIR) spectroscopy. It can be concluded that the microscopic morphology of the catalyst is porous. The main active components are amorphous MnO2 and multivalent iron oxides. Furthermore, the Fe-Mn/AC catalyst showed great reusability; the removal efficiency of COD was only reduced from 84% to 79% at the fourth reaction. Moreover, the COD removal efficiency could recover to 81% after catalyst regeneration.


Assuntos
Águas Residuárias , Poluentes Químicos da Água/análise , Compostos de Manganês , Compostos Orgânicos , Oxirredução , Óxidos
11.
Oncogene ; 38(24): 4820-4834, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30808975

RESUMO

The chromosome 8q24.21 locus, which contains the proto-oncogene c-MYC, long non-coding RNA PVT1, and microRNAs (miRs), is the most commonly amplified region in human prostate cancer. A long-range interaction of genetic variants with c-MYC or long non-coding PVT1 at this locus contributes to the genetic risk of prostate cancer. At this locus is a cluster of genes for six miRs (miR-1204, -1205, -1206, -1207-3p, -1207-5p, and -1208), but their functional role remains elusive. Here the copy numbers and expression levels of miRs-1204-1208 were investigated using quantitative PCR for prostate cancer cell lines and primary tumors. The data revealed that copy numbers and expression of miR-1205 were increased in both castration-resistant prostate cancer cell lines and in primary tumors. In castration-resistant prostate cancer specimens, the copy number at the miR-1205 locus correlated with the expression of miR-1205. Furthermore, functional analysis with an miR-1205 mimic, an miR-1205 inhibitor, and CRISPR/Cas9 knockout revealed that, in human prostate cancer cells, miR-1205 promoted cell proliferation and cell cycle progression and inhibited hydrogen peroxide-induced apoptosis. In these cells, miR-1205 downregulated the expression of the Egl-9 family hypoxia inducible factor 3(EGLN3) gene and targeted a site in its 3'-untranslated region to downregulate its transcriptional activity. Thus, by targeting EGLN3, miR-1205 has an oncogenic role and may contribute to the genetic risk of castration-resistant prostate cancer.


Assuntos
Adenocarcinoma/genética , Proliferação de Células/genética , Prolina Dioxigenases do Fator Induzível por Hipóxia/genética , MicroRNAs/fisiologia , Neoplasias de Próstata Resistentes à Castração/genética , Adenocarcinoma/patologia , Idoso , Idoso de 80 Anos ou mais , Animais , Cromossomos Humanos Par 8/genética , Regulação Neoplásica da Expressão Gênica , Predisposição Genética para Doença , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Pessoa de Meia-Idade , Células PC-3 , Neoplasias de Próstata Resistentes à Castração/patologia , Fatores de Risco , Células Tumorais Cultivadas
12.
Environ Technol ; 40(23): 3062-3071, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29659333

RESUMO

The coagulant dosage of an existing water plant is mainly determined based on the experience of water treatment process and influent/effluent water quality indexes that have time hysteresis effects. To solve this problem, the effect of coagulant dosage on a number of parameters used to evaluate the efficiency of flocculation in a setup was determined by using the micro-vortex flocculation technology in conjunction with the investigation of the relation between the equivalent diameter and the fractal dimension. By means of the machine vision system and computerized analysis, the effects of floc quantity, floc equivalent diameter and fractal dimension can be assessed. The correlations of these parameters with turbidity and ζ potential of the settling water, taken as measures for effluent quality, were explored. The study results show that the optimal flocculation effect with a turbidity removal rate of 97.9% is achieved at the poly-aluminum chloride dosage of 20 mg/L. Meanwhile, a power exponential relation between the floc equivalent diameter and the fractal dimension was established with a correlation coefficient R2 of 0.826; relations among the effluent turbidity and the floc quantity, equivalent diameter, fractal dimension were established with a correlation coefficient R2 of 0.982, 0.851, and 0.875, respectively; equations between the ζ potential and the floc quantity, equivalent diameter, fractal dimension were also established where the correlation coefficient R2 were 0.868, 0.879, and 0.942, respectively. These results may provide excellent reference data for water plants to feed back the coagulant by floc performance parameters, which could relieve the hysteresis effect efficiently.


Assuntos
Purificação da Água , Floculação , Fractais , Eliminação de Resíduos Líquidos , Água
13.
J Environ Manage ; 220: 173-182, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29778953

RESUMO

In this work, a series of flower-like CuAl layered double hydroxides (LDHs) and hierarchical CuAl/carbon fiber-LDH (CuAl/CF-LDH) materials were synthesized, and these materials were used as catalysts for the degradation of ammonia nitrogen from simulated wastewater. The morphologies and structures of the materials were characterized using scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy (RS), X-ray diffraction (XRD), and the Brunauer-Emmett-Teller (BET) technique. The effects of the catalyst and H2O2 loading dosages, reaction temperature, pH, Cu/Al ratio of the samples, and contact time on the degradation process were investigated by degrading ammonia nitrogen under different conditions, and the possible degradation mechanism was discussed. CuAl/CF-LDH exhibited more effectively catalytically degradation of ammonia nitrogen than others as-prepared samples, and removal efficiency reached 99.7% under the optimized conditions. The reusing capability and stability of the materials were studied. Meanwhile, the versatility of the materials was investigated by testing their performance in the absorption of azo dye, the highest removal efficiency was found to be 99.28%. The prepared materials are promising for use as effective catalysts for the degradation of ammonia nitrogen from wastewater.


Assuntos
Amônia , Carbono , Águas Residuárias/química , Adsorção , Fibra de Carbono , Peróxido de Hidrogênio , Hidróxidos , Cinética , Nitrogênio
14.
J Cancer ; 9(6): 1096-1105, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29581789

RESUMO

Targeted therapies based on EGFR mutations or on the ALK fusion oncogene have become the standard treatment for certain patients with lung adenocarcinoma (LUAD). However, most LUAD patients have no EGFR mutation or ALK fusion, and their oncogenetic alterations remain to be characterized. Here we conducted an integrated analysis of public datasets to assess the genomic alterations of 23 highly lung cancer-associated genes. The copy numbers of these genes were measured in ten micro-dissected, paired tumors and normal lung tissues of LUAD patients without EGFR mutations or ALK fusion. The copy numbers of PTEN, RB1, HMGA2, and PTPRD were lower in tumors compared with those for normal tissues. Although there were reduced mRNA levels of PTEN and RB1 in tumors, there was a correlation between copy number and expression only for PTEN. In addition, analysis of the copy number alterations of these 23 genes revealed correlations between EMSY/CCND1, EMSY/PIK3CA, CCND1/CDKN2A, and CCND1/PIK3CA. Our exploration of integrated copy number and gene expression analysis gives priority to the PTEN-PIK3CA and RB1-CCND1 pathways in developing therapeutic strategies for LUAD patients without EGFR mutations or ALK fusion.

15.
J Environ Manage ; 208: 159-168, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29268183

RESUMO

Nano-Fe3O4 was used as heterogeneous catalyst to activate Na2S2O8 for the generation of the sulfate radicals (SO4-) to oxidize the residual pollutants in landfill leachate biochemical effluent. The oxidation performance, wastewater spectral analysis and activator characterization were discussed. Oxidation experimental result shows that nano-Fe3O4 has obvious catalytic effect on Na2S2O8 and can significantly enhance the oxidation efficiencies of Na2S2O8 on landfill leachate biochemical effluent, with COD and color removals above 63% and 95%, respectively. Based on the analyses of three-dimensional excitation emission matrix fluorescence spectrum (3DEEM), ultraviolet-visible spectra (UV-vis), and Fourier Transform infrared spectroscopy (FTIR) of wastewater samples before and after treatment, it can be concluded that the pollution level of dissolved organic matter (DOM) declined and that the humic acid (HA) fractions were efficiently degraded into small molecules of fulvic acid (FA) fractions with less weight and stable structure. Compared to the raw wastewater sample, the aromaticity and substituent groups of the DOM were lessened in the treated wastewater sample. Moreover, the main structure of the organics and functional groups were changed by the Fe3O4/Na2S2O8 system, with substantial decrease of conjugated double bonds. The micro morphology of nano-Fe3O4 was characterized before and after reaction by the methods of scanning electron microscope spectra (SEM), X-ray diffraction pattern (XRD), and X-ray photoelectron spectroscopy (XPS). The XRD pattern analysis showed that nano-Fe3O4 was oxidized into r-Fe2O3 and that the particle size of it also became smaller after reaction. XPS was employed to analyze the content and iron valence on the nano-Fe3O4 surface, and it can be found that the ratio of Fe3+/Fe2+ decreased from 1.8 before reaction to 0.8 after reaction. From the SEM analysis after the treatment, it was determined that the spacing between nano-Fe3O4 was increased, but in turn, the particles decreased in diameter.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Compostos Férricos , Substâncias Húmicas , Oxirredução
16.
Bioresour Technol ; 249: 924-934, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29145119

RESUMO

Amine-functionalized magnetic bamboo-based activated carbon (AFM-BAC) derived from bamboo products wastes were employed for effective adsorption of fluoroquinolone antibiotics ciprofloxacin (CIP) and norfloxacin (NOR) through batch processing. The effects of factors on the adsorption of both antibiotics were studied. The studies of various factors influencing the adsorption behavior indicated that the maximum adsorption capacities for two antibiotics adsorption were observed in weakly acidic condition and the adsorption amounts of two antibiotics increased with the increase of zwitterionic form, implying the importance of zwitterionic form, and the adsorption process is spontaneous and endothermic. The result of date indicated that adsorption of both two antibiotics onto the AFM-BAC better fits Langmuir isotherm model. The saturated magnetization of AFM-BAC reached 8.55 emu g-1. A fixed-bed column adsorption with a bench-scale was carried out. Desorption and regeneration experiments showed that the AFM-BAC for both antibiotics could remain above 80% after five consecutive recycling cycles.


Assuntos
Ciprofloxacino , Norfloxacino , Poluentes Químicos da Água , Purificação da Água , Adsorção , Aminas , Carbono , Carvão Vegetal
17.
J Colloid Interface Sci ; 460: 349-60, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26385593

RESUMO

The performances of ordered mesoporous carbon CMK-3 (OMC), bamboo-based carbon (BC), and these two kinds of adsorbents modified by thermal treatment in the ammonia atmosphere at high temperatures were evaluated for the removal fluoroquinolone antibiotic (ciprofloxacin) from aqueous solution. The adsorption behavior of ciprofloxacin (CIP) onto OMC and BC including adsorption isotherms and kinetics were investigated. The effect of various factors (pH, ionic strength and temperature) on the adsorption process was also investigated. The results demonstrated that the modified OMC and BC can further enhance the adsorption capacity due to introduce of alkaline nitrogen functionalities on the carbon surface. And their maximum adsorption capacity reached as high as 233.37mgg(-1) and 362.94mgg(-1) under the same experimental conditions, respectively. This is primarily ascribed to the positive effect of the surface basicity. The highest sorption was observed at the lowest solubility, which indicated that hydrophobic interaction was the dominant sorption mechanism for CIP uptake onto the four adsorbents. The adsorption data of antibiotics was analyzed by Langmuir and Freundlich model, and the better correlation was achieved by the Langmuir isotherm. The kinetic data showed that the adsorption of CIP onto OMC and BC follow closely the pseudo-second order model. The removal efficiency and adsorption capacity increased with increasing temperature. The results of thermodynamic study indicated that the adsorption process was a spontaneous and endothermic.

18.
Int J Rheum Dis ; 15(2): 154-62, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22462418

RESUMO

AIMS: To describe clinical features of patients with ankylosing spondylitis (AS) from southern and northern China, and investigate the effects of onset age, gender and regional differences on disease phenotype. METHODS: Totally 113 AS patients from southern China and 121 AS patients from northern China were analyzed retrospectively. RESULTS: In southern and northern groups, low back pain was more frequent among initial symptoms (54.9% vs. 7.7%; 52.4% vs. 11.4%), while peripheral arthritis (15.7% vs. 35.9%; 22.2% vs. 68.6%) was less common in male adult AS (AAS) than in male juvenile AS (JAS) patients, respectively. Compared to those in the northern group, diagnostic delay was longer (7.3 vs. 3.5 years) and the prevalence of human leukocyte antigen (HLA)-B27 was higher in the southern group (96.5% vs. 83.5%). Sacroiliitis grade 2 was more frequent (51.3% vs. 36.4%), while sacroiliitis grade 3 (32.7% vs. 53.7%), buttock pain (5.3% vs. 13.2%), knee (20.4% vs. 33.1%) and ankle (3.5% vs. 11.6%) arthritis were less frequent in the southern group. Diagnostic delay of southern JAS was longer than that of northern JAS regardless of gender. Both sacroiliitis grade 3 and peripheral arthritis were less frequent in southern male JAS than in northern male JAS. Diagnostic delay was longer, sacroiliitis grade 2 was more frequent, while sacroiliitis grade 3 was less frequent in southern male AAS than those in northern male AAS. CONCLUSION: Significant diagnostic delay and higher prevalence of HLA-B27 were found in southern AS patients. The prevalence of buttock pain and peripheral arthritis at disease onset in northern AS was more frequent than in southern AS patients.


Assuntos
Artrite/diagnóstico , Dor Lombar/diagnóstico , Espondilite Anquilosante/diagnóstico , Adulto , Idade de Início , Artrite/epidemiologia , Artrite/genética , China/epidemiologia , Comorbidade , Diagnóstico Tardio/estatística & dados numéricos , Feminino , Predisposição Genética para Doença , Geografia , Antígeno HLA-B27 , Humanos , Articulações/patologia , Articulações/fisiopatologia , Dor Lombar/epidemiologia , Dor Lombar/genética , Masculino , Índice de Gravidade de Doença , Fatores Sexuais , Espondilite Anquilosante/epidemiologia , Espondilite Anquilosante/genética , Adulto Jovem
19.
Anal Chim Acta ; 683(2): 187-91, 2011 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-21167969

RESUMO

A sensitive electrochemical sensor has been fabricated to detect ultratrace nitroaromatic explosives using ordered mesoporous carbon (OMC). OMC was synthesized and characterized by scanning electron microscopy, transmission electron microscopy and nitrogen adsorption/desorption measurements. Glassy carbon electrodes functionalized with OMC show high sensitivity of 62.7 µA cm(-2) per ppb towards 2,4,6-trinitrotoluene (TNT). By comparison with other materials such as carbon nanotubes and ordered mesoporous silica, it is found that the high performance of OMC toward sensing TNT is attributed to its large specific surface area and fast electron transfer capability. As low as 0.2 ppb TNT, 1 ppb 2,4-dinitrotoluene and 1 ppb 1,3-dinitrobenzene can be detected on OMC based electrodes. This work renders new opportunities to detect ultratrace explosives for applications of environment protections and home securities against chemical warfare agents.


Assuntos
Carbono/química , Técnicas Eletroquímicas/métodos , Substâncias Explosivas/análise , Dinitrobenzenos/análise , Eletrodos , Nanotubos de Carbono/química , Nanotubos de Carbono/ultraestrutura , Porosidade , Dióxido de Silício/química , Trinitrotolueno/análise
20.
Chem Commun (Camb) ; 46(5): 689-91, 2010 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-20087488

RESUMO

For the first time, a multilayered WO(3) x H(2)O/PVA membrane on bacteriorhodopsin (bR) is constructed to significantly enhance the photoelectric response of bR by the spillover effect of WO(3) x H(2)O nanocrystals, providing great potential in its important applications in bioelectronics and proton exchange membrane fuel cells.


Assuntos
Bacteriorodopsinas/química , Membranas Artificiais , Nanoestruturas/química , Óxidos/química , Álcool de Polivinil/química , Tungstênio/química , Água/química , Tamanho da Partícula , Fotoquímica , Propriedades de Superfície
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