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1.
Int J Biometeorol ; 61(11): 1919-1925, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28567499

RESUMO

This panel study investigates how temperature, humidity, and their interaction affect chronic obstructive pulmonary disease (COPD) patients' self-reported symptoms. One hundred and six COPD patients from Shanghai, China, were enrolled, and age, smoking status, St. George Respiratory Questionnaire (SGRQ) score, and lung function index were recorded at baseline. The participants were asked to record their indoor temperature, humidity, and symptoms on diary cards between January 2011 and June 2012. Altogether, 82 patients finished the study. There was a significant interactive effect between temperature and humidity (p < 0.0001) on COPD patients. When the indoor humidity was low, moderate, and high, the indoor temperature ORs were 0.969 (95% CI 0.922 to 1.017), 0.977 (0.962 to 0.999), and 0.920 (95% CI 0.908 to 0.933), respectively. Low temperature was a risk factor for COPD patients, and high humidity enhanced its risk on COPD. The indoor temperature should be kept at least on average at 18.2 °C, while the humidity should be less than 70%. This study demonstrates that temperature and humidity were associated with COPD patients' symptoms, and high humidity would enhance the risk of COPD due to low temperature.


Assuntos
Umidade , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Temperatura , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Saúde Gerados pelo Paciente , Autorrelato , Avaliação de Sintomas
2.
Asian Pac J Allergy Immunol ; 34(1): 21-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26994622

RESUMO

OBJECTIVE: This study investigated correlations between meteorological and environmental factors (MEFs) and allergic rhinitis in childhood (ARC). METHODS: Children who received treatment for AR and meteorological data that might have influenced AR in the same time period were included in this study. Daily average maximum values of sulfur dioxide (SO2), nitrogen dioxide (NO2), and particulate matter (PM10) at 3 a.m. and 8 a.m. were provided by the Shanghai Environmental Bureau for statistical analysis using a generalized additive model (GAM). RESULTS: Outpatient visits for ARC were higher, with a bimodal shape, for daily average temperatures of about 11 ° C and 21 ° C. However, increasing humidity was associated with a downward trend in outpatient visits for ARC, suggesting that high humidity had a protective effect on AR. When levels of air pollutants such as O3, SO2, and PM10 increased by 10 µg/m3, AR outpatient visits increased by 1.95%, 1.19% and 0.33%, respectively, suggesting that air pollution might increase the risk of AR episodes. CONCLUSIONS: MEFs were significantly correlated with the incidence of ARC.


Assuntos
Rinite Alérgica/epidemiologia , Adolescente , Poluição do Ar/efeitos adversos , Criança , Pré-Escolar , Feminino , Humanos , Umidade , Incidência , Masculino , Dióxido de Nitrogênio/análise , Material Particulado/análise , Estudos Retrospectivos , Rinite Alérgica/etiologia , Dióxido de Enxofre/análise
3.
BMC Int Health Hum Rights ; 14: 8, 2014 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-24661722

RESUMO

BACKGROUND: The one-child policy introduced in China in 1979 has led to far-reaching changes in socio-demographic characteristics. Under this policy regime, each household has few children. This study aims to describe the prevalence of child neglect in one-child families in China and to examine the correlates of child neglect. METHODS: A cross-sectional study of 2044 children aged 6 to 9 years and recruited from four primary schools in Suzhou City, China was conducted. Neglect subtypes were determined using a validated indigenous measurement scale reported by parents. Child, parental and family characteristics were obtained by questionnaires and review of social security records. Linear regression analyses were performed to estimate the associations between these factors and the subtypes of child neglect. RESULTS: The prevalence of child any neglect was 32.0% in one child families in Suzhou City, China. Supervisory (20.3%) neglect was the most prevalent type of child neglect, followed by emotional (15.2%), physical (11.1%), and educational (6.0%) neglect After simultaneous adjustment to child and family characteristics and the school factor, boys, children with physical health issues and cognitive impairment, younger and unemployed mother, were positively associated with neglect subtypes. We also found that parents with higher education and three-generation families were negatively associated with neglect. CONCLUSION: The rates of child neglect subtypes vary across different regions in China probably due to the different policy implementation and socio-economic levels, with a lower level of physical and educational neglect and a higher level of emotional neglect in this study. The three-generation family structure was correlates of neglect which may be unique in one child families. This indicates that future intervention programs in one-child families should target these factors.


Assuntos
Maus-Tratos Infantis/estatística & dados numéricos , Características da Família/etnologia , Política de Planejamento Familiar , Análise de Variância , Criança , Maus-Tratos Infantis/classificação , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Modelos Lineares , Masculino , Poder Familiar/etnologia , Prevalência , Fatores de Risco , Distribuição por Sexo , Fatores Socioeconômicos , População Urbana/estatística & dados numéricos
4.
Opt Express ; 21(24): 29277-82, 2013 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-24514480

RESUMO

The zinc oxide (ZnO) nanowire arrays on the indium tin oxide (ITO) glass substrates were fabricated by using the two-step hydrothermal method. A high transmittance ~92% of ZnO nanowire arrays on ITO substrate in the visible region was obtained. It was observed that the liquid crystal (LC) directors were aligned vertically to the (ZnO) nanowire arrays. The properties of ZnO nanowire arrays as vertical liquid crystal (LC) alignment layers and their applications for hybrid-aligned nematic LC modes were investigated in this work.

5.
Environ Res ; 120: 27-32, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22981950

RESUMO

There is only limited monitoring data of black carbon for epidemiologic analyses. In the current study, we used the distributed lag models to evaluate the association between mortality outcomes (both total and cause-specific) and exposure to black carbon and fine particle (PM(2.5)) in Shanghai, China. During our research period, the mean daily concentrations of black carbon and PM(2.5) were 3.9 µg/m3 and 53.9 µg/m3, respectively. The regression results showed that black carbon was significantly associated with total and cardiovascular mortality, but not with respiratory mortality. An inter-quartile range increase (2.7 µg/m3) of black carbon corresponded to a 2.3% (95% confidence interval [CI]: 0.6-4.1), 3.2% (95% CI: 0.6-5.7), and 0.6% (95% CI: -4.5 to 5.7) increase in total, cardiovascular and respiratory mortality, respectively. When adjusted for PM(2.5), the effects of black carbon increased and remained statistically significant; in contrast, the associations of PM(2.5) with daily mortality decreased and became statistically insignificant after adjustment for black carbon. To our knowledge, this is the first study in China, or even in Asian developing countries, to report the acute effect of black carbon and PM(2.5) on daily mortality simultaneously. Our findings suggest that black carbon is a valuable additional air quality indicator to evaluate the health risks of ambient particles.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Poluição do Ar/estatística & dados numéricos , Doenças Cardiovasculares/mortalidade , Transtornos Respiratórios/mortalidade , Fuligem/efeitos adversos , Adolescente , Adulto , Idoso , Poluição do Ar/efeitos adversos , Criança , Pré-Escolar , China , Cidades , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Adulto Jovem
6.
Cyberpsychol Behav Soc Netw ; 26(1): 3-10, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36454251

RESUMO

This study examined two ways of using the TikTok application (active vs. passive use), and their association with female users' self-esteem pertaining to appearance and weight. By adopting a cross-sectional online survey design, this study recruited 7,750 adult female TikTok users from China (Douyin), and acquired self-reported data on 2 ways of using TikTok, state-level social comparison, appearance-esteem, weight-esteem, body mass index, and age. The results indicated that passive and active TikTok uses were negatively and positively associated with participants' appearance- and weight-esteem, respectively. A mediation analysis revealed that the participants' state-level social comparison while using TikTok mediated the association between two ways of TikTok use, and their effects on appearance- and weight-esteem. These results help us understand the complicated impact of TikTok use on body image, and design campaigns for promoting body acceptance.


Assuntos
Imagem Corporal , Mídias Sociais , Adulto , Humanos , Feminino , Comparação Social , Estudos Transversais , Autoimagem
7.
Front Psychol ; 13: 846390, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35465502

RESUMO

Previous studies have reported that general or photo-specific social media use was associated with women's body dissatisfaction and body image disturbance. The current study replicated and expanded upon these findings by identifying the positive association between social media influencer viewing and intentions to change appearance. This study surveyed a sample of 7,015 adult female TikTok users in China regarding their social media influencer viewing frequency, self-objectification, social comparison tendencies when watching short videos, intentions to change appearance, and demographics. The results showed that female TikTok users' self-objectification mediated the association between their influencer viewing frequency and their intentions to change appearance. Furthermore, social comparison tendencies moderated the association between influencer viewing and intentions to change appearance in that the proposed association was stronger for female TikTok users who had lower social comparison tendencies when watching short videos, compared to female TikTok users who had higher social comparison tendencies. The counter-intuitive finding on social comparison tendencies indicated that women who have higher social comparison tendencies may be more aware of the negative influences and adjust their expectations. The observed association between social media influencer viewing and intentions to change appearance was statistically significant but trivial in terms of effect size. Although the result could warn policymakers and practitioners to design media and health literacy campaigns to cultivate body positivity, caution should be exercised when evaluating the practical implications.

8.
Front Psychol ; 10: 2221, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31681068

RESUMO

A growing body of research explores emoji, which are visual symbols in computer mediated communication (CMC). In the 20 years since the first set of emoji was released, research on it has been on the increase, albeit in a variety of directions. We reviewed the extant body of research on emoji and noted the development, usage, function, and application of emoji. In this review article, we provide a systematic review of the extant body of work on emoji, reviewing how they have developed, how they are used differently, what functions they have and what research has been conducted on them in different domains. Furthermore, we summarize directions for future research on this topic.

9.
Oncotarget ; 9(25): 17406-17419, 2018 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-29707116

RESUMO

Allergic rhinitis (AR) is a chronic inflammatory disorder driven by T cell activation. How particulate matter contributes to epigenetic changes that in turn influence cytokine gene expression in CD4+T cells remains unclear. In this study, 105 children diagnosed with AR and 90 healthy controls were recruited to explore the possible mechanism of particulate matter (PM) on the epigenetic regulation of CD4+T IFN-γ and IL-4 promoter genes. Daily average PM10 and PM2.5 were obtained from five state-controlled monitoring stations, and activity-based dynamic exposure and personal exposure data were collected. DNA methylation patterns of IFN-γ and IL-4 promoter regions were analyzed using bisulfite sequencing. mRNA levels were detected by real-time quantitative reverse transcription polymerase chain reaction. We found that the methylation rate in IFN-γ was higher in AR CD4+T cells than in the controls. IFN-γ mRNA expression was significantly decreased in CD4+T cells, and negatively correlated with the mean methylation level of IFN-γ. However, no correlation between IL-4 methylation and IL-4 mRNA expression was found. After adjusting for age, gender, exclusive breastfeeding within 4 months after birth and parental history of allergic disease, out data showed that PM2.5 exposure level was positively correlated with methylation level in IFN-γ promoter region and decreased cytokine expression. We conclude that the effect of PM2.5 on pediatric AR may be mediated through epigenetic modification of IFN-γ promoter region.

10.
Chemosphere ; 204: 251-256, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29660538

RESUMO

The volatile fatty acids (VFA) concentration plays important roles in the rapid start-up and stable operation of anaerobic reactors. It's essential to develop a simple and accurate method to monitor the VFA concentration in the anaerobic systems. In present work, a modified two-point titration method was developed to determine the VFA concentration. The results show that VFA concentration in standard solutions estimated by the titration method coincided well with that measured by gas chromatograph, where all relative errors were lower than 5.5%. Compared with the phosphate, ammonium and sulfide subsystems, the effect of bicarbonate on the accuracy of the developed method was relatively significant. When the bicarbonate concentration varied from 0 to 8 mmol/L, the relative errors increased from 1.2% to 30% for VFA concentration at 1 mmol/L, but were within 2.0% for that at 5 mmol/L. In addition, the VFA composition affected the accuracy of the titration method to some extent. This developed titration method was further proved to be effective with practical effluents from a lab-scale anaerobic reactor under organic shock loadings and an unstable full-scale anaerobic reactor.


Assuntos
Reatores Biológicos , Ácidos Graxos Voláteis/análise , Ácidos Graxos Voláteis/química , Anaerobiose , Cromatografia Gasosa
11.
Artigo em Inglês | MEDLINE | ID: mdl-28208759

RESUMO

Background: Air pollution has been demonstrated to be a major risk factor for the development of cardiovascular and respiratory diseases worldwide. This study examines the relationship between the exposure to fine particulate matter (PM) and patient hospitalizations as a result of ischemic heart disease (IHD) during 2013-2014 in Shanghai, China. Methods: Daily IHD hospitalization data were acquired from the Shanghai Health Insurance Bureau (SHIB) from 1 January 2013 to 21 December 2014. Daily average concentrations of air pollution as well as meteorological data were obtained from the database of Shanghai Environmental Monitoring Center (SEMC) during the same time period, and all data were analyzed using standard epidemiological methodology. Generalized linear model (GLM) adjusted for time trends, weather conditions, and medical insurance policy was used to estimate the immediate and delayed effects of PMs on IHD hospitalizations, and the effects of PMs were also examined based on gender, age group and seasonal variation. Results: A total of 188,198 IHD hospitalizations were recorded during 2013-2014 in Shanghai, China. During this period, the average concentrations of the fine particulate matter with aerodynamic diameter of <10 µm (PM10) and ≤2.5 (PM2.5) were 76 µg/m³ and 56.3 µg/m³, respectively. The effect of PMs was strongest on days when a 10 µg/m³ increment increase of PM2.5 and PM10, which coincided with an increase in IHD hospitalizations by 0.25% (95% CI: 0.10%, 0.39%) and 0.57% (95% CI: 0.46%, 0.68%), respectively. Furthermore, the effect of PMs was significantly greater in males and people between 41 and 65 years old. Conclusions: Hospitalizations of IHD was strongly associated with short-term exposure to high levels of PM10 and PM2.5 during 2013-2014 in Shanghai, China.


Assuntos
Poluentes Atmosféricos/toxicidade , Poluição do Ar/efeitos adversos , Hospitalização/estatística & dados numéricos , Isquemia Miocárdica/etiologia , Material Particulado/toxicidade , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Poluição do Ar/estatística & dados numéricos , China/epidemiologia , Monitoramento Ambiental , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/epidemiologia , Isquemia Miocárdica/terapia , Material Particulado/análise , Fatores de Risco , Estações do Ano , Fatores Sexuais , Tempo (Meteorologia)
12.
PLoS One ; 11(3): e0151119, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26942767

RESUMO

INTRODUCTION: Evidence based on ecological studies in China suggests that short-term exposure to particulate matter (PM) is associated with cardiovascular mortality. However, there is less evidence of PM-related morbidity for coronary heart disease (CHD) in China. This study aims to investigate the relationship between acute PM exposure and CHD incidence in people aged above 40 in Shanghai. METHODS: Daily CHD events during 2005-2012 were identified from outpatient and emergency department visits. Daily average concentrations for particulate matter with aerodynamic diameter less than 10 microns (PM10) were collected over the 8-year period. Particulate matter with aerodynamic diameter less than 2.5 microns (PM2.5) were measured from 2009 to 2012. Analyses were performed using quasi-poisson regression models adjusting for confounders, including long-term trend, seasonality, day of the week, public holiday and meteorological factors. The effects were also examined by gender and age group (41-65 years, and >65 years). RESULTS: There were 619928 CHD outpatient and emergency department visits. The average concentrations of PM10 and PM2.5 were 81.7 µg/m3 and 38.6 µg/m3, respectively. Elevated exposure to PM10 and PM2.5 was related with increased risk of CHD outpatients and emergency department visits in a short time course. A 10 µg/m3 increase in the 2-day PM10 and PM2.5 was associated with increase of 0.23% (95% CI: 0.12%, 0.34%) and 0.74% (95% CI: 0.44%, 1.04%) in CHD morbidity, respectively. The associations appeared to be more evident in the male and the elderly. CONCLUSION: Short-term exposure to high levels of PM10 and PM2.5 was associated with increased risk of CHD outpatient and emergency department visits. Season, gender and age were effect modifiers of their association.


Assuntos
Poluição do Ar/efeitos adversos , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/etiologia , Material Particulado/efeitos adversos , China/epidemiologia , Serviço Hospitalar de Emergência , Humanos , Incidência , Pacientes Ambulatoriais/estatística & dados numéricos , Tamanho da Partícula
13.
Sci Rep ; 6: 23858, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-27033635

RESUMO

Allergic conjunctivitis is a common problem that significantly impairs patients' quality of life. Whether air pollution serves as a risk factor for the development of allergic conjunctivitis remains elusive. In this paper, we assess the relationship between air pollutants and weather conditions with outpatient visits for allergic conjunctivitis. By using a time-series analysis based on the largest dataset ever assembled to date, we found that the number of outpatient visits for allergic conjunctivitis was significantly correlated with the levels of NO2, O3, and temperature, while its association with humidity was statistically marginal. No associations between PM10, PM2.5, SO2, or wind velocity and outpatient visits were seen. Subgroup analyses showed that sex seemed to modify the effects of humidity on outpatient visits for allergic conjunctivitis, but not for NO2, O3, or temperature. People younger than 40 were found to be susceptible to changes of all four parameters, while those older than 40 were only consistently affected by NO2 levels. Our findings revealed that higher levels of ambient NO2, O3, and temperature increase the chances of outpatient visits for allergic conjunctivitis. Ambient air pollution and weather changes may contribute to the worsening of allergic conjunctivitis.


Assuntos
Poluição do Ar , Instituições de Assistência Ambulatorial/estatística & dados numéricos , Conjuntivite Alérgica/epidemiologia , Conceitos Meteorológicos , Visita a Consultório Médico/estatística & dados numéricos , Adulto , Fatores Etários , China/epidemiologia , Conjuntivite Alérgica/etiologia , Feminino , Humanos , Umidade , Masculino , Pessoa de Meia-Idade , Dióxido de Nitrogênio/análise , Ozônio/análise , Material Particulado , Sistema de Registros , Estudos Retrospectivos , Dióxido de Enxofre/análise , Temperatura
14.
Chemosphere ; 140: 12-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25907762

RESUMO

Microbial fuel cells (MFCs) have gained tremendous global interest over the last decades as a device that uses bacteria to oxidize organic and inorganic matters in the anode with bioelectricity generation and even for purpose of bioremediation. However, this prospective technology has not yet been carried out in field in particular because of its low power yields and target compounds removal which can be largely influenced by electron acceptors contributing to overcome the potential losses existing on the cathode. This mini review summarizes various electron acceptors used in recent years in the categories of inorganic and organic compounds, identifies their merits and drawbacks, and compares their influences on performance of MFCs, as well as briefly discusses possible future research directions particularly from cathode aspect.


Assuntos
Fontes de Energia Bioelétrica/microbiologia , Águas Residuárias/microbiologia , Bactérias , Eletrodos , Elétrons , Oxidantes , Oxirredução , Estudos Prospectivos , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química
15.
ACS Appl Mater Interfaces ; 7(18): 9619-24, 2015 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-25895105

RESUMO

The control of the liquid crystal (LC) alignment is very important for both academic research and practical applications. LC molecules aligned on the ZnO nanoparticle arrays (ZnO NPAs) are demonstrated and the pretilt angles of LCs can be controlled by using ZnO NPAs with different surface wettability. The wettability of ZnO NPAs fabricated by the solution-based hydrothermal method can be controlled by changing the annealing temperature of the as-prepared ZnO NPAs. The measurements of the energy-dispersive spectra and photoluminescence have shown that the chemical properties of ZnO NPAs have been changed with the annealing temperature. Our results show that the pretilt angle of LCs can be tuned continuously from ∼0 to ∼90° as the contact angle of water on ZnO NPAs changes from 33 to 108°.

16.
Biosens Bioelectron ; 26(2): 470-6, 2010 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-20692154

RESUMO

Simultaneous electricity generation and sulfide removal can be achieved in a microbial fuel cell (MFC). In electricity harvesting from sulfide oxidation in such an MFC, various microbial communities are involved. It is essential to elucidate the microbial communities and their roles in the sulfide conversion and electricity generation. In this work, an MFC was constructed to enrich a microbial consortium, which could harvest electricity from sulfide oxidation. Electrochemical analysis demonstrated that microbial catalysis was involved in electricity output in the sulfide-fed MFC. The anode-attached and planktonic communities could perform catalysis independently, and synergistic interactions occurred when the two communities worked together. A 16S rRNA clone library analysis was employed to characterize the microbial communities in the MFC. The anode-attached and planktonic communities shared similar richness and diversity, while the LIBSHUFF analysis revealed that the two community structures were significantly different. The exoelectrogenic, sulfur-oxidizing and sulfate-reducing bacteria were found in the MFC anodic chamber. The discovery of these bacteria was consistent with the community characteristics for electricity generation from sulfide oxidation. The exoelectrogenic bacteria were found both on the anode and in the solution. The sulfur-oxidizing bacteria were present in greater abundance on the anode than in the solution, while the sulfate-reducing bacteria preferably lived in the solution.


Assuntos
Fontes de Energia Bioelétrica/microbiologia , Eletricidade , Proteobactérias/genética , Proteobactérias/isolamento & purificação , Sulfetos/metabolismo , Oxirredução , Proteobactérias/classificação , Especificidade da Espécie
17.
Environ Sci Technol ; 43(9): 3372-7, 2009 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-19534160

RESUMO

Sulfide oxidation is coupled with electricity generation in a sulfide-fed microbial fuel cell (MFC). This study demonstrated that both electrochemical reactions and microbial catalysis were involved in such a complex sulfide oxidation process in the anode of an MFC. The microbe-assisted sulfide oxidation generated a higher persistent current density than the sulfide oxidation via single electrochemical reactions only. Three valence states of S (-II), S (0), and S (+VI) were discovered from the sulfide oxidation, and So, Sx(2-), S4O6(2-), S2O3(2-), and SO4(2-) were detected as the intermediates. Based on the sulfur speciation and microbial community analysis, the sulfide oxidation pathways in the MFC were proposed. The oxidation of sulfide to So/Sx(2-) and further to S4O6(2-)/S2O3(2-) occurred spontaneously as electrochemical reactions, and electricity was generated. The formation of So/Sx(2-) and S2O3(2-) was accelerated by the bacteria in the MFC anode, and SO4(2-) was generated because of a microbial catalysis. The microbe-assisted production of S2O3(2-) and SO4(2-) resulted in a persistent current from the MFC.


Assuntos
Fontes de Energia Bioelétrica/microbiologia , Sulfetos/metabolismo , Bactérias Redutoras de Enxofre/metabolismo , Reatores Biológicos/microbiologia , Eletricidade , Eletrodos/microbiologia , Oxirredução , Soluções , Análise Espectral , Enxofre/metabolismo
18.
Environ Sci Technol ; 42(21): 8095-100, 2008 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-19031908

RESUMO

Microbial fuel cells (MFCs) are devices that use bacteria as the catalysts to oxidize organic and inorganic matter and generate current whereas microbial electrolysis cells (MECs) are a reactor for biohydrogen production by combining MFC and electrolysis. In an MEC, an external voltage must be applied to overcome the thermodynamic barrier. Here we report an MEC-MFC-coupled system for biohydrogen production from acetate, in which hydrogen was produced in an MEC and the extra power was supplied by an MFC. In this coupled system, hydrogen was produced from acetate without external electric power supply. At 10 mM of phosphate buffer, the hydrogen production rate reached 2.2 +/- 0.2 mL L(-1) d(-1), the cathodic hydrogen recovery (RH2) and overall systemic Coulombic efficiency (CEsys) were 88 to approximately 96% and 28 to approximately 33%, respectively, and the overall systemic hydrogen yield (Y(sysH2)) peaked at 1.21 mol-H2 mol-acetate(-1). The hydrogen production was elevated by increasing the phosphate buffer concentration, and the highest hydrogen production rate of 14.9 +/- 0.4 mL L(-1) d(-1) and Y(sysH2) of 1.60 +/- 0.08 mol-H2 mol-acetate(-1) were achieved at 100 mM of phosphate buffer. The performance of the MEC and the MFC was influenced by each other. This MEC-MFC-coupled system has a potential for biohydrogen production from wastes, and provides an effective way for in situ utilization of the power generated from MFCs.


Assuntos
Acetatos/metabolismo , Bactérias/citologia , Bactérias/metabolismo , Fontes de Energia Bioelétrica , Eletrólise , Hidrogênio/metabolismo , Soluções Tampão , Eletricidade , Soluções
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