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1.
Molecules ; 29(5)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38474539

RESUMO

Catalytic oxidation is widely recognized as a highly effective approach for eliminating highly toxic CO. The current challenge lies in designing catalysts that possess exceptional low-temperature activity and stability. In this work, we have prepared ultrafine platinum particles of ~1 nm diameter dispersed on a MgFe2O4 support and found that the addition of 3 wt.% FeOx into the 3Pt/MgFe2O4 significantly improves its activity and stability. At an ultra-low temperature of 30 °C, the CO can be totally converted to CO2 over 3FeOx-3Pt/MgFe2O4. High and stable performances of CO-catalytic oxidation can be obtained at 60 °C on 3FeOx-3Pt/MgFe2O4 over 35 min on-stream at WHSV = 30,000 mL/(g·h). Based on a series of characterizations including BET, XRD, ICP, STEM, H2-TPR, XPS, CO-DRIFT, O2-TPD and CO-TPD, it was disclosed that the relatively high activity and stability of 3FeOx-3Pt/MgFe2O4 is due to the fact that the addition of FeOx could facilitate the antioxidant capacity of Pt and oxygen mobility and increase the proportion of adsorbed oxygen species and the amounts of adsorbed CO. These results are helpful in designing Pt-based catalysts exhibiting higher activity and stability at low temperatures for the catalytic oxidation of CO.

2.
BMC Cardiovasc Disord ; 21(1): 565, 2021 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-34836509

RESUMO

BACKGROUND: The diagnosis of malignant pericardial effusion (MPE) is often associated with a poor prognosis, but due to the complexity and unspecific nature of MPE patients' clinical manifestations, imaging often performs an essential role in diagnosis and prognosis. METHODS: Patients diagnosed with MPE between 2013 and 2018 at one tumor hospital were included and followed up. The data covered the basic clinical features, imaging findings, treatments and prognosis of patients with MPE, and the factors that may have affected the prognosis were explored. RESULTS: A total of 216 patients with MPE were included with the median age of 60 years. The most common primary cancer type was lung cancer (73.6%), the most common symptom was dyspnea (62.9%) and the most common abnormal electrocardiogram finding was sinus tachycardia (42.1%). The median survival time of the 216 patients with MPE was 13.7 months. The factors affecting prognosis were echocardiographic fluid signs (HR = 2.37, P = 0.010), electrocardiographic evidence of sinus tachycardia (HR = 1.76, P = 0.006) and echocardiographic evidence of cardiac tamponade (HR = 3.33, P < 0.001). CONCLUSIONS: MPE has complex clinical manifestations and an unsatisfactory prognosis. Echocardiographic fluid signs, electrocardiographic evidence of sinus tachycardia, and echocardiographic evidence of cardiac tamponade are independent risk factors affecting prognosis.


Assuntos
Ecocardiografia , Neoplasias/complicações , Derrame Pericárdico/diagnóstico por imagem , Derrame Pericárdico/etiologia , Idoso , Tamponamento Cardíaco/diagnóstico por imagem , Tamponamento Cardíaco/etiologia , China , Dispneia/etiologia , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/diagnóstico , Neoplasias/mortalidade , Neoplasias/terapia , Derrame Pericárdico/mortalidade , Derrame Pericárdico/terapia , Valor Preditivo dos Testes , Prognóstico , Medição de Risco , Fatores de Risco , Avaliação de Sintomas , Taquicardia Sinusal/diagnóstico , Taquicardia Sinusal/etiologia , Fatores de Tempo
3.
ACS Appl Mater Interfaces ; 8(2): 1128-38, 2016 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-26741170

RESUMO

A rapid, efficient technique for the attachment of bacteriophages (phages) onto polyhydroxyalkanoate (PHA) surfaces has been developed and compared to three reported methods for phage immobilization. Polymer surfaces were modified to facilitate phage attachment using (1) plasma treatment alone, (2) plasma treatment followed by activation by 1-ethyl-3-(3-(dimethylamino)propyl)carbodiimide hydrochloride (EDC) and N-hydroxysulfosuccinimide (sulfo-NHS), (3) plasma-initiated acrylic acid grafting, or (4) plasma-initiated acrylic acid grafting with activation by EDC and sulfo-NHS. The impact of each method on the surface chemistry of PHA was investigated using contact angle analysis and X-ray photoelectron spectroscopy. Each of the four treatments was shown to result in both increased hydrophilicity and in the modification of the surface functional groups. Modified surfaces were immersed in suspensions of phage T4 for immobilization. The highest level of phage binding was observed for the surfaces modified by plasma treatment alone. The change in chemical bond states observed for surfaces that underwent plasma treatment is suspected to be the cause of the increased binding of active phages. Plasma-treated surfaces were further analyzed through phage-staining and fluorescence microscopy to assess the surface density of immobilized phages and their capacity to capture hosts. The infective capability of attached phages was confirmed by exposing the phage-immobilized surfaces to the host bacteria Escherichia coli in both plaque and infection dynamic assays. Plasma-treated surfaces with immobilized phages displayed higher infectivity than surfaces treated with other methods; in fact, the equivalent initial multiplicity of infection was 2 orders of magnitude greater than with other methods. Control samples - prepared by immersing polymer surfaces in phage suspensions (without prior plasma treatment) - did not show any bacterial growth inhibition, suggesting they did not bind phages from the suspension.


Assuntos
Bacteriófago T4/química , Bacteriófagos/química , Técnicas Biossensoriais , Poli-Hidroxialcanoatos/química , Bacteriófago T4/metabolismo , Escherichia coli/química , Espectroscopia Fotoeletrônica , Succinimidas/química , Propriedades de Superfície
4.
Nat Biotechnol ; 30(6): 549-54, 2012 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-22580950

RESUMO

Foxtail millet (Setaria italica), a member of the Poaceae grass family, is an important food and fodder crop in arid regions and has potential for use as a C(4) biofuel. It is a model system for other biofuel grasses, including switchgrass and pearl millet. We produced a draft genome (∼423 Mb) anchored onto nine chromosomes and annotated 38,801 genes. Key chromosome reshuffling events were detected through collinearity identification between foxtail millet, rice and sorghum including two reshuffling events fusing rice chromosomes 7 and 9, 3 and 10 to foxtail millet chromosomes 2 and 9, respectively, that occurred after the divergence of foxtail millet and rice, and a single reshuffling event fusing rice chromosome 5 and 12 to foxtail millet chromosome 3 that occurred after the divergence of millet and sorghum. Rearrangements in the C(4) photosynthesis pathway were also identified.


Assuntos
Biocombustíveis , Evolução Molecular , Genoma de Planta , Setaria (Planta)/genética , Mapeamento Cromossômico , Cicloexanonas/farmacologia , Bases de Dados Genéticas , Resistência a Medicamentos , Marcadores Genéticos/genética , Família Multigênica , Fotossíntese/genética , Filogenia , Análise de Sequência de DNA
5.
J Colloid Interface Sci ; 357(2): 273-9, 2011 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-21377165

RESUMO

In this work, the surface characteristics of poly(N-vinyl-2-pyrrolidone) (PNVP)-modified nonwoven fabric (NWF) membranes and the effects of the surface characteristics on the membranes antifouling properties were investigated. Effects of grafting time, grafting temperature, and monomer concentration on the grafting degree of PNVP were systematically investigated. The effect of grafting degree on the surface characteristics was also investigated. Scanning electron microscopy (SEM) was used to characterize the structural and morphological changes on the membrane surface. The water contact angles decreased from 113±1.2° to 52±3°, which means that the hydrophilicity of the modified NWF was enhanced with increasing PNVP grafting degree. The surface free energy was calculated, which showed an increase after modification. Static bovine serum albumin (BSA) adsorption experiments were carried out, which showed a decrease of 82.5%. Permeation experiments of water and supernatant solution of active sludge were carried out to determine the antifouling characteristics against the extracellular polymeric substance. Results demonstrated that the modified NWF had higher permeation fluxes and lower flux loss in comparison with the original NWF. Bacterial adhesion on the membrane surface was largely suppressed after the introduction of PNVP.


Assuntos
Incrustação Biológica/prevenção & controle , Membranas Artificiais , Polipropilenos/química , Pirrolidinonas/química , Poluentes Químicos da Água , Animais , Aderência Bacteriana , Bovinos , Interações Hidrofóbicas e Hidrofílicas , Microscopia Eletrônica de Varredura , Estrutura Molecular , Soroalbumina Bovina/química , Propriedades de Superfície
6.
Bioresour Technol ; 101(14): 5469-74, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20202832

RESUMO

To prepare a high flux and antifouling filtration membrane used for submerged membrane bioreactors, non-woven fabric (NWF) was modified by coating chitosan (CS) on both internal and outer surface. Chemical structural and morphological changes were characterized. The changes of surface free energy were monitored by dynamic contact angle, which showed an increase after modification. The CS/NWF composite membranes were found to be with high flux, high effluent quality and excellent antifouling property. The results of fouling resistance distribution indicated that irreversible fouling resistance was decreased by coating CS. Especially, there were fewer gel layers existing on the outer surface. The adsorption of EPS on the NWF membrane internal surface decreased after being coated with CS. Modification improved filtration performance, and made fouling less troublesome and membrane regeneration efficient.


Assuntos
Reatores Biológicos , Quitosana/química , Membranas Artificiais , Adsorção , Animais , Biotecnologia/métodos , Bovinos , Filtração , Permeabilidade , Polímeros/química , Proteínas/química , Propriedades de Superfície
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