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1.
Bioresour Technol ; 402: 130841, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38750830

RESUMO

Activation of peroxymonosulfate (PMS) with solid catalysts for organic pharmaceutical degradation still faces challenge due to the demand of inexpensive catalysts. In this study, manganese-oxidizing microalgae (MOM) and its associated biogenic manganese oxides (BMO) were employed to prepare biomass-transformed porous-carbon/manganese (B-PC/Mn) catalyst through high-temperature calcination (850 °C). Remarkably, 100 % of carbamazepine (CBZ) was degraded within 30 min in the B-PC/Mn/PMS system. The degradation kinetic constant was 0.1718 min-1, which was 44.0 times higher than that of the biomass-transformed porous carbon mixed with MnOx activated PMS system. 1O2 was generated in the B-PC/Mn/PMS system, which is responsible for CBZ degradation. The MOM-BMO-associated structure greatly increased the specific surface areas and the contents of the C = O and pyrrolic-N groups, which facilitated PMS activation. The structure also induced the generation of Mn5C2, which exhibited a strong adsorption towards PMS. This study provides a novel strategy for preparing catalysts by using waste biomass.


Assuntos
Biomassa , Carbamazepina , Carbono , Manganês , Peróxidos , Carbamazepina/química , Catálise , Porosidade , Peróxidos/química , Carbono/química , Manganês/química , Cinética , Poluentes Químicos da Água/química , Microalgas/metabolismo , Óxidos/química , Compostos de Manganês/química , Adsorção
2.
Cell Mol Biol (Noisy-le-grand) ; 69(1): 81-86, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-37213153

RESUMO

In this experiment, the effects of biofilm on neurovascular unit functions and neuroinflammation of patients with ischemic cerebral stroke were investigated. For this purpose, 20 adult male rats were purchased from Taconic (8 to 10 weeks old, weighing between 20 and 24g) and selected as the research objects. Then, they were randomly divided into an experimental group (10 rats) and a control group (10 rats). Ischemic cerebral stroke rat models were established. Besides, pseudomonas aeruginosa (PAO1) was prepared manually and implanted into the bodies of rats in the experimental group. mNSS scores, cerebral infarction area, and the release of inflammatory cytokines of rats in the two groups were compared. Results showed that mNSS scores for rats in the experimental group at all periods were remarkably higher than those for rats in the control group (P<0.05), which demonstrated that the rats in the experimental group suffered much severer neurological impairment than those in the control group. In addition, the release of tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-1ß, inducible nitric oxide synthase (iNOS), and IL-10 were all higher than those of the control group (P<0.05). The cerebral infarction area of the experimental group at all periods was remarkably larger than that of the control group (P<0.05). In conclusion, the formation of biofilm led to the aggravation of neurological impairment and inflammatory reactions among patients with ischemic cerebral stroke.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Ratos , Masculino , Animais , Doenças Neuroinflamatórias , Inflamação , Fator de Necrose Tumoral alfa , Interleucina-6 , Infarto Cerebral , Infarto da Artéria Cerebral Média/complicações
3.
Biodegradation ; 33(6): 621-639, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36214905

RESUMO

The enhanced biodegradation of oil-contaminated soil by fixing microorganisms with corn cob biochar was investigated. It was found that the components of oil in the test soil were mainly straight-chain alkanes and branched alkanes. When using corn cob biochar as a carrier to immobilize microorganisms, the best particle size of corn cob biochar as an immobilization carrier was 0.08 mm, and the best immobilization time was 18 h. SEM analysis confirmed that the microorganisms were immobilized on the corn cob biochar. Immobilized microorganisms exhibited high biodegradability under stress to high concentrations of petroleum pollutants, heavy metals, and organic pollutants. Infrared spectroscopy analysis showed that oxygen-containing groups such as hydroxyl, carboxyl, and methoxy on the surface of biochar were involved in the complexation of heavy metals. The mechanism of immobilization promoted microbial degradation of oil contamination was explained by gas chromatography mass. First, alkanes and aromatics were adsorbed by corn cob biochar and passed to immobilized microorganisms to promote their degradation. Their bioavailability increased, especially for aromatics. Second, biochar provided a more suitable environment for microorganisms to degrade. Third, the conversion of ketones to acids was accelerated during the biodegradation of alkanes, and the biodegradation of alkanes was accelerated by immobilization. The biodegradable efficiency of oil by immobilized microorganisms in soil was 70.10% within 60 days, 28.80% higher than that of free microorganisms. The degradation of immobilized microorganisms was highly correlated with the activities of catalase, urease, and polyphenol oxidase.


Assuntos
Metais Pesados , Petróleo , Poluentes do Solo , Biodegradação Ambiental , Gás Natural , Catalase , Poluentes do Solo/análise , Urease , Carvão Vegetal , Petróleo/análise , Solo/química , Microbiologia do Solo , Alcanos , Oxigênio/análise , Cetonas , Catecol Oxidase
4.
Chemosphere ; 262: 127968, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33182104

RESUMO

Electrocoagulation (EC) coupled with E-peroxone process (ECP) was a promising and cost-effective integrated technology for shale gas fracturing flowback water (SGFFW) treatment. In this study, the ECP process was comprehensively compared with two sequential processes (EC followed by E-peroxone (EC-E-peroxone) and E-peroxone followed by EC (E-peroxone-EC)) to elucidate the synergistic effect of this coupled process. In EC-E-peroxone process, COD decreased by 89.2%, while COD decreased by 82.5% for 180 min in E-peroxone-EC process. However, COD removal efficiency was 82.4% in ECP for only 90 min. Average current efficiency of the ECP process was 29.9%, which was twice than that of the sequential processes. The enhancement factor was calculated to be 1.63, demonstrating the substantial significant synergistic effects for ECP. Only low MW components could be observed for the EC-E-peroxone (average MW = 533 Da with PD ≈ 1) and ECP process (MW = 538 Da with PD ≈ 1). These results suggested that EC-E-peroxone and ECP process had much stronger oxidation ability, demonstrating the enhancement of OH production induced by the Al-based coagulants might be responsible for the significant enhancement of COD removal. These results indicated there could be a synergistic effect between EC and ozone in addition to EC and E-peroxone reactions. Compared to the two sequential processes, ECP was a high efficiency and space-saving electrochemical system with simultaneous coagulation and enhanced OH generation by the products of anode and the cathode.


Assuntos
Técnicas Eletroquímicas/métodos , Peróxido de Hidrogênio/química , Gás Natural/análise , Ozônio/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Análise da Demanda Biológica de Oxigênio , China , Eletrodos , Floculação , Fraturamento Hidráulico , Oxirredução , Águas Residuárias/química
5.
Fish Shellfish Immunol ; 98: 534-550, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32004614

RESUMO

The present study evaluated the effects of (2-Carboxyethyl)dimethylsulfonium Bromide (Br-DMPT) supplementation on the intestinal immune function and potential mechanisms of on-growing grass carp (Ctenopharyngodon idella) by feeding fish (initial weight 216.49 ± 0.29 g) five diets with gradational Br-DMPT (0-520 mg/kg diet) concentrations for 60 days and then infecting them with Aeromonas hydrophila for 14 days. Our results firstly indicated that compared with the control group, appropriate Br-DMPT supplementation increased the number of beneficial bacteria Lactobacillus and Bifidobacterium and enteritis resistance, decreased the number of detrimental bacteria Aeromonas and E. coli, and relieved the intestinal histopathological symptoms of fish. In addition, compared with the control group, appropriate Br-DMPT supplementation (1) increased lysozyme (LZ) and acid phosphatase (ACP) activities, as well as complement 3 (C3), C4 and immunoglobulin M (IgM) content; (2) upregulated the mRNA levels of anti-microbial substance: liver expressed anti-microbial peptide (LEAP) -2A, LEAP-2B, hepcidin, ß-defensin-1 and Mucin2; (3) partially downregulated the mRNA levels of pro-inflammatory cytokines [interleukin 1ß (IL-1ß), IL-6, IL-8, IL-12p40, IL-15, IL-17D, tumour necrosis factor α (TNF-α) and interferon γ2 (IFN-γ2)] by inhibiting [IKKß/IκBα/(NF-κBp65 and c-Rel)] signalling; and (4) partially upregulated the mRNA levels of anti-inflammatory cytokines [IL-4/13A, IL-10, IL-11, transforming growth factor (TGF)-ß1] by activating [TOR/(S6K1 and 4E-BP)] signalling. The aforementioned results indicated that appropriate amount of Br-DMPT exerted a positive effect on the regulation of intestinal immune function in fish. Finally, based on enteritis morbidity, the IgM content and the lysozyme activity in the PI, the appropriate levels of Br-DMPT supplementation for on-growing grass carp were established as 295.43, 301.73 and 320.36 mg/kg diet, respectively.


Assuntos
Carpas , Intestinos/efeitos dos fármacos , Intestinos/imunologia , Compostos de Sulfônio/farmacologia , Animais , Antiulcerosos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Intestinos/microbiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
6.
Water Environ Res ; 88(5): 403-7, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27131304

RESUMO

Ozonation of real dye wastewater for removal of color and COD reduction covering a wide range in operating parameters forms the scope of the present work. The influence of parameters such as influent pH, ozone flow rate and initial effluent concentration on ozonation efficiency has been critically examined. It has been observed from the present investigation that a maximum of COD removal efficiency of 92.5% has been achieved under optimum operating conditions (pH=11; ozone flow rate: 6×10(-3) m(3)/minute). Further the biodegradability index of the dye effluent has increased from an initial value of 0.18 to 0.49 during ozonation indicating favorable adaptation of ozonation as a primer to the biochemical technique to enhance the efficiency of biochemical treatment.


Assuntos
Corantes/análise , Ozônio/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Biodegradação Ambiental , Análise da Demanda Biológica de Oxigênio , Indústria Têxtil
7.
Water Environ Res ; 86(2): 141-6, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24645544

RESUMO

Ozone oxidation is an advanced oxidation process for treatment of organic and inorganic wastewater. In this paper, sodium acetate (according to chemical oxygen demand [COD]) was selected as the model pollutant in water, and the degradation efficiencies and mechanism of sodium acetate in water by ozone oxidation were investigated. The results showed that the ozone oxidation was an effective treatment technology for advanced treatment of sodium acetate in water; the COD removal rate obtained the maximum value of 45.89% from sodium acetate solution when the pH value was 10.82, ozone concentration was 100 mg/L, reaction time was 30 minutes, and reaction temperature was 25 degrees C. The COD removal rate increased first and decreased subsequently with the bicarbonate (HCO3-) concentration from 0 to 200 mg/L, the largest decline being 20.35%. The COD removal rate declined by 25.38% with the carbonate (CO3(2-)) concentration from 0 to 200 mg/L; CO3(2-) has a more obvious scavenging effect to inhibit the formation of hydroxyl free radicals than HCO3-. Calcium chloride (CaCl2) and calcium hydroxide (Ca(OH)2) could enhance the COD removal rate greatly; they could reach 77.35 and 96.53%, respectively, after a reaction time of 30 minutes, which was increased by 31.46 and 50.64%, respectively, compared with only ozone oxidation. It was proved that the main ozone oxidation product of sodium acetate was carbon dioxide (CO2), and the degradation of sodium acetate in the ozone oxidation process followed the mechanism of hydroxyl free radicals.


Assuntos
Acetato de Sódio/química , Água/química , Análise da Demanda Biológica de Oxigênio , Cloreto de Cálcio/química , Hidróxido de Cálcio/química , Carbonatos/química , Oxirredução , Ozônio/química
8.
Zhonghua Nan Ke Xue ; 14(4): 328-30, 2008 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-18481425

RESUMO

OBJECTIVE: To evaluate the effect of circumcision on the glans penis sensitivity by comparing the changes of the glans penis vibrotactile threshold between normal men and patients with simple redundant prepuce and among the patients before and after the operation. METHODS: The vibrotactile thresholds were measured at the forefinger and glans penis in 73 normal volunteer controls and 96 patients with simple redundant prepuce before and after circumcision by biological vibration measurement instrument, and the changes in the perception sensitivity of the body surface were analyzed. RESULTS: The G/F (glans/finger) indexes in the control and the test group were respectively 2.39 +/- 1.72 and 1.97 +/- 0.71, with no significant difference in between (P > 0.05). And those of the test group were 1.97 +/- 0.71, 2.64 +/- 1.38, 3.09 +/-1.46 and 2.97 +/- 1.20 respectively before and 1, 2 and 3 months after circumcision, with significant difference between pre- and post-operation (P < 0.05). CONCLUSION: There is a statistic difference in the glans penis vibration perception threshold between normal men and patients with simple redundant prepuce. The glans penis perception sensitivity decreases after circumcision.


Assuntos
Circuncisão Masculina , Ereção Peniana/fisiologia , Adulto , Humanos , Masculino , Limiar Sensorial
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