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1.
J Hazard Mater ; 424(Pt C): 127622, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34749999

RESUMO

A novel magnetic hydrochar synthesized from Fenton sludge (FS) and sewage sludge (SS) was employed in the anaerobic decolorization of acid orange 7 (AO7). The stable presence of Fe3O4 in magnetic hydrochar was confirmed by physicochemical characterization. The degradation efficiency of AO7 in the anaerobic system with the addition of hydrochar prepared in an optimal proportion (SS:FS=1:3, named as HC-1:3) could reach 98.55%, which was 1.91 times higher than the control system. Particularly, superior electrical conductivity, electron transport system activity and azo reductase activity of the sludge in anaerobic system with HC-1:3 were achieved. The redox of Fe(Ⅲ)/Fe(Ⅱ) in anaerobic system was realized by dissimilatory iron-reducing bacteria enriched with HC-1:3. According to the six-cycle batch experiments and 120-day continuous-flow UASB experiments, the addition of HC-1:3 into the anaerobic system facilitated the diversity of microbiological community and increased the ecological stability of anaerobic system. The possible electron transfer mechanism involving in the magnetic hydrochar-based anaerobic system for AO7 removal was speculated preliminarily. The as-prepared magnetic hydrochar not only showed a promising future in anaerobic system for recalcitrant contaminants degradation, but also provided a new approach for the resource utilization of FS and SS.


Assuntos
Esgotos , Eliminação de Resíduos Líquidos , Anaerobiose , Compostos Azo , Benzenossulfonatos , Reatores Biológicos , Corantes , Compostos Férricos , Fenômenos Magnéticos
2.
Small ; 18(2): e2105217, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34796651

RESUMO

Boosting the replacement of traditional NH3 production (Haber-Bosch process) with photocatalytic technology is of great importance for energy and environment remediation. Herein, to develop a photocatalyst with efficient charge separation and abundant reactive sites for photocatalytic N2 fixation, a biomass-induced diphase-carbon doping strategy is proposed by adding lotus root starch which can be environmentally produced into the preparation of carbon nitride (CN). The adjustment to the CN framework by planar-fused carbon optimizes the band alignment of the catalyst, improving its response to sunlight. In particular, the in-plane-fused carbon in collaboration with the physically piled carbon initiates unique dual electron transfer pathways from different dimensions. The diphasic carbons can both function as qualified reactive sites according to the experimental explorations and further theoretical calculations, which effectively regulate the electron transfer and energy barrier associated with the N2 reduction on catalyst. The bio-carbon-doped catalyst exhibits drastically enhanced photocatalytic N2 fixation performance, and the NH3 yield on the optimized DC-CN0.1 reaches 167.35 µmol g-1 h-1 , which is fivefold of g-C3 N4 and stands far out from the single-phase doped systems. These explorations expand the metal-free skeleton engineering toolbox and provide new guidance for the solar energy utilizations.


Assuntos
Carbono , Nitrilas , Biomassa , Eletrônica , Nitrilas/química
3.
Chemosphere ; 247: 125832, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31931312

RESUMO

Anaerobic reduction of nitrobenzene (NB) can be efficiently enhanced bySupplementing withSulfide-modified nanoscale zerovalent iron (S-nZVI). In thisStudy,S/Fe ratio ofS-nZVI was further optimized for enhancing biological NB removal in anaerobicSystem amended withS-nZVI and inoculated by anaerobicSludge. The results indicated that the performance andStability of the coupled anaerobicSystem for NB reduction and aniline formation were remarkably improved byS-nZVI atS/Fe molar ratio of 0.3 (0.3S-nZVI). TheSecretion of extracellular polymericSubstances (EPS), transformation of volatile fatty acids (VFAs), yield of methane and activity ofSeveral key enzymes could be efficiently improved by 0.3S-nZVI. Furthermore,Species related to NB reduction, fermentation, electroactivity and methanogenesis could be enriched in 0.3S-nZVI coupled anaerobicSystem, with remarkable improvement in the biodiversity observed. ThisStudy demonstrated thatSulfidation would be a promising method to improve the performance of nZVI in coupled anaerobicSystems for the removal of recalcitrant nitroaromatic compounds from wastewater.


Assuntos
Ferro/análise , Nitrobenzenos/isolamento & purificação , Sulfetos/análise , Poluentes Químicos da Água/metabolismo , Anaerobiose , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Ferro/farmacologia , Metano/biossíntese , Metano/metabolismo , Nitrobenzenos/metabolismo , Sulfetos/farmacologia , Águas Residuárias/química , Poluentes Químicos da Água/análise
4.
Sci Total Environ ; 694: 133701, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31386958

RESUMO

In our previous study, biochar (BC) supported sulfidated nano zerovalent iron (S-nZVI@BC) was prepared for nitrobenzene (NB) reduction. In this study, in order to further improve the reduction performance of S-nZVI@BC, BC was modified before the loading of S-nZVI through three methods: oxidant (H2O2) pretreatment, alkali (NaOH) pretreatment and acid (HCl) pretreatment. The results indicated that S-nZVI could be evenly distributed onto HCl-BC due to increased surface area, negative surface charge and increased acidic functional groups on HCl-BC. At an initial concentration of 200 mg L-1, NB could be completely removed by S-nZVI@HCl-BC within a reaction time as short as 60 min, indicating rather excellent performance of S-nZVI@HCl-BC. NB reduction performance followed the order: S-nZVI@HCl-BC > S-nZVI@NaOH-BC > S-nZVI@BC > S-nZVI@H2O2-BC. The mass ratio of S-nZVI and HCl-BC was optimized in terms of NB removal efficiency, with 3:1 being identified as the best mass ratio. Furthermore, the mechanism involved in the enhanced NB reduction by S-nZVI@HCl-BC was proposed. This study demonstrated that S-nZVI@HCl-BC is a promising alternative for efficient NB removal from wastewater.


Assuntos
Nitrobenzenos/química , Poluentes Químicos da Água/química , Adsorção , Carvão Vegetal/química , Ferro , Nitrobenzenos/análise , Poluentes Químicos da Água/análise
5.
J Int Med Res ; 47(4): 1580-1591, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30832524

RESUMO

OBJECTIVES: The principal diagnostic methods of traditional Chinese medicine (TCM) are inspection, auscultation and olfaction, inquiry, and pulse-taking. Treatment by syndrome differentiation is likely to be subjective. This study was designed to provide a basic theory for TCM diagnosis and establish an objective means of evaluating the correctness of syndrome differentiation. METHODS: We herein provide the basic theory of TCM syndrome computer modeling based on a noninvasive cardiac electrophysiology imaging technique. Noninvasive cardiac electrophysiology imaging records the heart's electrical activity from hundreds of electrodes on the patient's torso surface and therefore provides much more information than 12-lead electrocardiography. Through mathematical reconstruction algorithm calculations, the reconstructed heart model is a machine-readable description of the underlying mathematical physics model that reveals the detailed three-dimensional (3D) electrophysiological activity of the heart. RESULTS: From part of the simulation results, the imaged 3D cardiac electrical source provides dynamic information regarding the heart's electrical activity at any given location within the 3D myocardium. CONCLUSIONS: This noninvasive cardiac electrophysiology imaging method is suitable for translating TCM syndromes into a computable format of the underlying mathematical physics model to offer TCM diagnosis evidence-based standards for ensuring correct evaluation and rigorous, scientific data for demonstrating its efficacy.


Assuntos
Algoritmos , Simulação por Computador , Eletrofisiologia , Imageamento Tridimensional/métodos , Medicina Tradicional Chinesa/métodos , Deficiência da Energia Yang/diagnóstico , Deficiência da Energia Yin/diagnóstico , Adolescente , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Síndrome , Yin-Yang , Adulto Jovem
6.
Zhonghua Liu Xing Bing Xue Za Zhi ; 34(3): 214-7, 2013 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-23759223

RESUMO

OBJECTIVE: To investigate the risk of HBV infection among the spouses of hepatitis B virus surface antigen (HBsAg) carriers and to provide a reference for developing strategies on hepatitis B control and prevention. METHODS: A case-control study including HBsAg carriers aged 20 - 45 years-old from the nationwide sero-epidemiological survey for Hepatitis B in both Guangdong and Jiangxi provinces in 2006, together with their spouses were selected as case group, while. HBsAg negative persons and their spouses were among the control groups, under the same residential areas, gender, age and age of marriage to the HBsAg carriers. Questionnaire survey and hepatitis B serological markers detection were carried out, together with the HBV genotype detection among the HBsAg positive couples between husband and wife by PCR. RESULTS: Among the spouses of HBsAg carriers, the positive rate of HBsAg was 13.21%, while the rate was 6.29% for the spouse of HBsAg negative population, with difference statistically significant (χ² = 4.23, P < 0.05). HBsAg positive rate among spouses of the case group was higher than that in the control group. Among the spouses of HBsAg carriers, the HBsAg rate was positively correlated with the age of marriage, frequency of sexual intercourse and condom use. There were 21 pairs of HBsAg carriers between husband and wife, and HBV were isolated among 13 pairs, and there were 11 pairs carrying the same HBV genotype, accounting for 84.62%. HBV genotypes would include 8 pairs of type B and 3 pairs of type C. However, only 2 pairs were infected with different HBV genotype. CONCLUSION: High risks of HBV infection existed in the spouses of HBsAg carriers. It was important to ask the HBsAg carriers to take the initiative in informing their spouses, and carrying out the appropriate measures, such as safe sex or timely hepatitis B vaccination for the spouse of HBsAg carriers etc., so as to reduce the HBV transmission between husband and wife.


Assuntos
Portador Sadio , Hepatite B/epidemiologia , Cônjuges , Adulto , Portador Sadio/sangue , Portador Sadio/virologia , Estudos de Casos e Controles , Feminino , Genótipo , Hepatite B/virologia , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/genética , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
7.
Zhongguo Yi Miao He Mian Yi ; 16(2): 173-7, 2010 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-20575275

RESUMO

Hepatitis B virus (HBV) is one of the most dangerous risk factors of hepatocellular carcinoma (HCC). How HBV infection leads to the occurrence and development of HCC is complicated. It is not only related with physical condition of HBV infection host, environment, HBV genotype, HBV viral load and gene mutation, but also related with age of HBV infection host, types of infection, and host chromosome integration site.


Assuntos
Carcinoma Hepatocelular , Hepatite B , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/patologia , Hepatite B/complicações , Hepatite B/epidemiologia , Hepatite B/prevenção & controle , Hepatite B/transmissão , Antígenos de Superfície da Hepatite B/sangue , Vacinas contra Hepatite B , Humanos , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/patologia
8.
J Am Chem Soc ; 130(24): 7702-9, 2008 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-18489101

RESUMO

Poly(diiodiacetylene), or PIDA, is a conjugated polymer containing the poly(diacetylene) (PDA) backbone but with only iodine atom substituents. The monomer diiodobutadiyne (1) can be aligned in the solid state with bis(nitrile) oxalamide hosts by hydrogen bonds between oxalamide groups and weak Lewis acid-base interactions (halogen bonds) between nitriles and iodoalkynes. The resulting cocrystals start out pale blue but turn shiny and copper-colored as the polymerization progresses. The development of a crystallization methodology that greatly improves the yield of PIDA to about 50% now allows the full characterization of the polymer by X-ray diffraction, solid-state (13)C MAS NMR, Raman, and electron absorption spectroscopy. Comparison of a series of hosts reveals an odd-even effect in the topochemical polymerization, based on the alkyl chain length of the host. In the cocrystals formed with bis(pentanenitrile) oxalamide (4) and bis(heptanenitrile) oxalamide (6), the host/guest ratio is 1:2 and the monomer polymerizes spontaneously at room temperature, while in the case of bis(butanenitrile) oxalamide (3) and bis(hexanenitrile) oxalamide (5), where the host and guest form cocrystals in a 1:1 ratio, the polymerization is disfavored and does not go to completion. The topochemical polymerization can also be observed in water suspensions of micrometer-sized 6.1 cocrystals; the size distribution of these microcrystals, and the resulting polymer chains, can be controlled by sonication. Completely polymerized PIDA cocrystals show a highly resolved vibronic progression in their UV/vis absorption spectra. Extensive rinsing of the crystals in organic solvents such as methanol, THF, and chloroform separates the polymer from the soluble host. Once isolated, PIDA forms blue suspensions in a variety of solvents. The UV/vis absorption spectra of these suspensions match the cocrystal spectrum, without the vibronic resolution. However, they also include a new longer-wavelength absorption peak, associated with aggregation of the polymer chains.


Assuntos
Polímeros/síntese química , Polímeros/isolamento & purificação , Poli-Inos/química , Poli-Inos/síntese química , Poli-Inos/isolamento & purificação , Cristalização , Polímero Poliacetilênico , Análise Espectral Raman , Difração de Raios X
9.
Science ; 312(5776): 1030-4, 2006 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-16709780

RESUMO

Conjugated organic polymers generally must include large substituents for stability, either contained within or appended to the polymer chain. In polydiacetylenes, the substituents fulfill another important role: During topochemical polymerization, they control the spacing between the diyne monomers to produce an ordered polymer. By using a co-crystal scaffolding, we have prepared poly(diiododiacetylene), or PIDA, a nearly unadorned carbon chain substituted with only single-atom iodine side groups. The monomer, diiodobutadiyne, forms co-crystals with bis(nitrile) oxalamides, aligned by hydrogen bonds between oxalamide groups and weak Lewis acid-base interactions between nitriles and iodoalkynes. In co-crystals with one oxalamide host, the diyne undergoes spontaneous topochemical polymerization to form PIDA. The structure of the dark blue crystals, which look copper-colored under reflected light, has been confirmed by single-crystal x-ray diffraction, ultraviolet-visible absorption spectroscopy, and scanning electron microscopy.

10.
Zhonghua Yi Xue Za Zhi ; 85(4): 244-7, 2005 Jan 26.
Artigo em Chinês | MEDLINE | ID: mdl-15854485

RESUMO

OBJECTIVE: To determine accurately the incidence of heterotopic gastric mucosa in the upper esophagus (HGMUE) in China, and to study the macroscopic and microscopic aspects of the lesions and to evaluate the clinical importance of HGMUE. METHODS: A prospective study was made among a total of 15,228 consecutive patients, 8,573 male and 6,655 female, aged 54 (8-95), undergoing gastroscopy. Disease histories of all patients were carefully inquired, especially those regarding possible complaints including discomfort of throat and swallowing pain and so on. Special care was taken in the upper esophageal sphincter area to make sure whether the area was adequately inspected. Biopsy specimens from aberrant mucosa were obtained and the sections were stained with haematoxylin and eosin, and Giemsa stain for Helicobacter pylori. RESULTS: HGMUE was found in 39 patients (0.26%) with an average age of 50. Five patients with H. pylori infection in heterotopic gastric mucosa also presented the infection in the stomach. The gastric mucosa was gastric body type in 8 patients, transitional type in 11 patients, and antral pattern in 7 patients. Intestinal metaplasia was found in 5 patients, and mild atypical hyperplasia in 2 patients. An impressive finding was coexistent erosive gastritis in 14 patients (35.9%), Barrett's esophagus in one patient (2.6%), peptic ulcer in 8 patients (20.5%), and a patient had the complication of constriction in the upper esophagus. CONCLUSION: HGMUE is not rare in China. The presence of inlet patches is possibly correlated with specific symptoms. There are some severe complications in HGMUE, especially esophageal constriction. Close surveillance should be taken for rare cases with metaplasia or dysplasia in HGMUE.


Assuntos
Coristoma/diagnóstico , Doenças do Esôfago/diagnóstico , Mucosa Gástrica , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Coristoma/patologia , Doenças do Esôfago/patologia , Feminino , Gastroscopia , Humanos , Masculino , Pessoa de Meia-Idade
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