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1.
Ecotoxicol Environ Saf ; 208: 111673, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396005

RESUMO

In the present research, a bioremediation process was developed using solid complex bacterial agents (SCBA) through a combined two-step biodegradation process. Four isolated strains showed high efficiency for the degradation of total petroleum hydrocarbons (TPH) and the reduction of COD of the oily sludge, at 96.6% and 92.6%, respectively. The mixed strains together with bran prepared in form of SCBA exhibited improved performance compared to individual strains, all of which had an optimal temperature of around 35 °C. The use of SCBA provided advantages over commonly used liquid media for storage and transportation. The two-step process, consisting of firstly biosurfactant-assisted oil recovery and secondly biodegradation of the remaining TPH with SCBA, demonstrated the capability for treating oily sludge with high TPH content (>10 wt%) and short process period (60 days). The large-scale (5 tons oily sludge) field test, achieving a TPH removal efficiency of 93.8% and COD reduction of 91.5%, respectively, confirmed the feasibility and superiority of the technology for industrial applications.


Assuntos
Microbiota , Poluição por Petróleo/prevenção & controle , Petróleo/análise , Esgotos , Biodegradação Ambiental , Meios de Cultura , Hidrocarbonetos/análise , Hidrocarbonetos/metabolismo , Petróleo/metabolismo , Poluição por Petróleo/análise , Esgotos/química , Esgotos/microbiologia , Temperatura
2.
Bioresour Technol ; 287: 121442, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31085429

RESUMO

Biodegradation of crude heavy oil was investigated with Chelatococcus daeguensis HB-4 that was isolated from the produced fluid of Baolige Oilfield in China. Batch growth characterization and crude oil degradation tests confirmed HB-4 to be facultative anaerobic and able to degrade heavy oil. The oil degradation was found to occur through degrading long hydrocarbons chains to shorter ones, resulting in oil viscosity reduction. By mixing crude oil with glucose, or using sole crude oil as carbon source, the content of light fractions (C8-C22) increased by 4.97% while heavy fractions (C23-C37) decreased by 7.98%. It was also found that bioemulsifiers were produced rather than commonly observed biosurfactants in the fermentation process, which was attributed to the extracellular degradation of hydrocarbons. Core flooding tests demonstrated 20.5% oil recovery by microbial enhancement, and 59.8% viscosity reduction, showing potential of strain HB-4 for application in the oil industry, especially in enhanced heavy oil recovery.


Assuntos
Petróleo , Biodegradação Ambiental , China , Hidrocarbonetos , Campos de Petróleo e Gás
3.
Langmuir ; 28(42): 14845-8, 2012 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-23046108

RESUMO

Metal nanocrystals with high-index facets (HIFs) have drawn significant attention for their superior catalysis activity compared to that of low-index faces. However, because of the high surface energy of HIFs, it is still challenging to preserve HIFs during the growth of nanocrystals. In this study, highly selective Pt concave nanocubes (CNCs) with high-index {hk0} facets have been successfully prepared in a simple aqueous solution. The vital role of glycine as the surface controller in the formation of CNCs was demonstrated. These Pt CNCs exhibited enhanced specific activities toward the electro-oxidation of methanol and formic acid in comparison to commercial Pt black and Pt/C catalysts.


Assuntos
Glicina/química , Nanopartículas Metálicas/química , Platina/química , Catálise , Técnicas Eletroquímicas , Tamanho da Partícula , Propriedades de Superfície
4.
Sci Rep ; 2: 612, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22937221

RESUMO

Hydrogen bond is a typical noncovalent bond with its strength only one-tenth of a general covalent bond. Because of its easiness to fracture and re-formation, materials based on hydrogen bonds can enable a reversible behavior in their assembly and other properties, which supplies advantages in fabrication and recyclability. In this paper, hydrogen bond nanoscale networks have been utilized to separate water and oil in macroscale. This is realized upon using nanowire macro-membranes with pore sizes ~tens of nanometers, which can form hydrogen bonds with the water molecules on the surfaces. It is also found that the gradual replacement of the water by ethanol molecules can endow this film tunable transport properties. It is proposed that a hydrogen bond network in the membrane is responsible for this switching effect. Significant application potential is demonstrated by the successful separation of oil and water, especially in the emulsion forms.


Assuntos
Óleos/química , Água/química , Emulsões/química , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Compostos de Manganês/química , Nanofios/química , Nanofios/ultraestrutura , Óxidos/química
5.
Chem Commun (Camb) ; 48(47): 5925-7, 2012 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-22552214

RESUMO

A 3D macro-assembly with α-MnO(2) nanowires as flexible building blocks was obtained by a simple hydrothermal method. The sample with an interconnected open porous structure shows excellent mechanical strength, selective adsorption of cationic dyes and some certain types of toxic heavy metal ions.


Assuntos
Compostos de Manganês/química , Nanofios/química , Óxidos/química , Adsorção , Corantes/química , Violeta Genciana/química , Metais Pesados/química , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanofios/ultraestrutura , Porosidade , Difração de Pó , Espectrofotometria Ultravioleta , Poluentes Químicos da Água/química , Difração de Raios X
6.
Nanoscale ; 4(8): 2633-9, 2012 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-22402765

RESUMO

Pt-Pd bimetallic alloy nanostructures with highly selective morphologies such as cube, bar, flower, concave cube, and dendrite have been achieved through a facile one-pot solvothermal synthesis. The effects of shape-controllers (sodium dodecyl sulfate (SDS), ethylenediamine-tetraacetic acid disodium salt (EDTA-2Na), NaI) and solvents (water/DMF) on the morphologies were systematically investigated. The electrocatalytic activities of these Pt-Pd alloy nanostructures toward formic acid oxidation were tested. The results indicated that these alloy nanocrystals exhibited enhanced and shape-dependent electrocatalytic activity toward formic acid oxidation compared to commercial Pt black and Pt/C catalysts.

7.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-258001

RESUMO

<p><b>OBJECTIVE</b>To observe the clinical therapeutic effect of acupuncture combined with Chinese herbs on polycystic ovary syndrome of kidney deficiency and phlegm stasis type and probe into the mechanism.</p><p><b>METHODS</b>Sixty-three cases of polycystic ovary syndrome of kidney deficiency and phlegm stasis type were randomly divided in to a combined acupuncture and Chinese herb group (n=32) treated with acupuncture at Qihai (CV 6), Guanyuan (CV 4), et al. and oral administration of Chinese herbs, and a simple Chinese herb group (n=31) treated with oral administration of the same Chinese herbs as in the combined acupuncture and Chinese herb group. The therapeutic effects and changes of follicle stimulating hormone (FSH), luteotropic hormone (LH), testosterone (T) and LH/FSH were compared between the two groups.</p><p><b>RESULTS</b>The total effective rate was 93.8% in the combined acupuncture and Chinese herb group and 80.6% in the simple Chinese herb group, the former being significantly better than the latter (P < 0.05). The decrease of T in the combined acupuncture and Chinese herb group was significantly su perior to that in the simple Chinese herb group (P < 0.01).</p><p><b>CONCLUSION</b>Acupuncture combined with Chinese herb therapy is superior to the simple Chinese herb in the clinical therapeutic effect on polycystic ovary syndrome of kidney deficiency and phlegm stasis type and decrease of T level, indicating this method is a better one for polycystic ovary syndrome of kidney deficiency and phlegm stasis type.</p>


Assuntos
Adolescente , Adulto , Feminino , Humanos , Adulto Jovem , Terapia por Acupuntura , Medicamentos de Ervas Chinesas , Usos Terapêuticos , Rim , Fitoterapia , Síndrome do Ovário Policístico , Tratamento Farmacológico , Metabolismo , Terapêutica , Escarro , Metabolismo
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