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1.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 37(6): 611-615, 2021 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-34821093

RESUMO

Objective: To investigate the effects and mechanism of curcumol (CC) on liver function and fibrosis in rats of nonalcoholic fatty liver disease (NAFLD). Methods: The rat models of nonalcoholic steatohepatitis (NASH) combined with liver fibrosis were constructed by high-fat diet. Sixty SD rats were randomly divided into blank control group, model group (NASH), NASH + Compound Biejiarangan Troche (CBT) group (positive control group), and NASH + CC groups (25, 50, 100 mg/kg) , 10 rats in each group. The percentage of liver to body weight, and the levels of high density lipoprotein (HDL), triglyceride (TG), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured. The liver fibrosis was observed by HE staining. The expressions of α-smooth muscle actin (α-SMA) and positive staining of nuclear factor κB p65 (NF-κB p65) were detected by immunohistochemistry. The expression levels of α-SMA, matrix metalloproteinase-1 (MMP-1), tissue inhibitor of metalloproteinase-1 (TIMP-1) and toll-like receptor-4 (TLR4), transforming growth factor-activated kinase-1 (TAK1), NF-κB p65 and vascular cell adhesion molecule-1 (VCAM-1) were detected by Western blot. The expression levels of interleukin (IL-6, IL-10, IL-1ß) and tumor necrosis factor-α (TNF-α) were detected by enzyme linked immunosorbent assay (ELISA). Results: Compared with blank control group, the contents of HDL and IL-10 and the expression level of MMP-1 protein were decreased in model group significantly (P<0.05), while the levels of TG, ALT and AST, the positive rate of P65, α-SMA, TIMP-1, TLR4, TAK1, NF-κB p65, VCAM-1, IL-6, TNF-α and IL-1ß were increased significantly (P<0.05). Compared with model group, the levels of HDL, IL-10 and MMP-1 protein were significantly increased after treatment with CBT and CC (P<0.05), while the levels of TG, ALT, and AST, the positive rate of P65, α-SMA, TIMP-1, TLR4, TAK1, NF-κB p65, VCAM-1, IL-6, TNF-α and IL-1ß were decreased significantly (P<0.05). The improvement in model+high- concentration CC group was the most significant, and which in all concentration groups was lower than that in model+CBT group (P<0.05). Conclusion: CC can reduce inflammation response and improve liver function by regulating TLR4, TAK1 and NF-κB/p65 signaling pathway, and thus alleviating liver fibrosis, showing concentration-dependence within certain range.


Assuntos
Cirrose Hepática/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica , Sesquiterpenos/farmacologia , Animais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
2.
Water Sci Technol ; 81(5): 1080-1089, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32541124

RESUMO

Bismuth oxyhalides (BiOXs, X = Cl, Br and I) are emerging photocatalytic materials with unique layered structure, flexible band structure and superior photocatalytic activity. The purpose of this study was to develop a facile alcoholysis route to prepare BiOClxI1-x nanosheet solid solutions at room temperature. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), UV-vis diffuse reflectance spectroscopy (UV-vis DRS), photoluminescence emission spectroscopy (PL) and Brunauer-Emmett-Teller (BET) surface area analyzer were used to characterize the as-prepared photocatalysts. These results revealed that two-dimension BiOClxI1-x nanosheet solid solutions could be obtained with high percentage of {001} crystal facets exposed. Moreover, the formation of solid solution could regularly change the optical absorption thresholds and band gaps of BiOClxI1-x photocatalysts. The photocatalytic experiments indicated that BiOCl0.75I0.25 exhibited the highest photocatalytic performance for the degradation of Rhodamine B (RhB) under simulated sunlight irradiation and the photocatalytic process followed a pseudo-first-order kinetic equation. A possible mechanism of RhB photodegradation over BiOClxI1-x solid solutions was proposed based on the structural properties of BiOClxI1-x solid solutions and RhB photosensitization.


Assuntos
Luz , Água , Catálise , Rodaminas
3.
Ying Yong Sheng Tai Xue Bao ; 29(10): 3391-3397, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30325165

RESUMO

Urban green land is an important component of urban natural ecosystems, with critical ecosystem service functions. Based on the land use data of Shenyang in 2005, 2010 and 2015, this study estimated ecosystem service value (ESV) according to "equivalent value per unit area of ecosystem services for various ecosystems in China" and then analyzed its spatio-temporal characteristics and change rate. The results showed that arable land area significantly reduced by 3.5% from 2005 to 2010 and 10.9% from 2010 to 2015, respectively. Wood land area increased slightly, and the area of meadow increased by 17.2%. The ESV of green land in Shenyang increased from 11.76×108 yuan in 2005 to 23.48×108 yuan in 2010, and then decreased to 11.29×108 yuan in 2015. The annual change of ESV showed significant difference among different districts, with the highest occurring in Yuhong, Shenbei and Heping districts. The coefficient of variation (CV) was 64.9%, 60.4% and 40.8%, respectively. The ESV of green land varied significantly among diffe-rent districts, with higher values occurring in Huanggu, Shenbei and Dongling districts. Soil conservation function had the highest ESV, accounting for 15% of the total ESV. The food production function had the lowest ESV. The changes of ESV in Shenyang might be attributed to the urban expansion, agricultural land conversion, and green space construction.


Assuntos
Ecossistema , Agricultura , China , Conservação dos Recursos Naturais
4.
Water Sci Technol ; 77(11-12): 2929-2939, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30065145

RESUMO

The development of a catalyst with high catalytic activity was one of the most important issues for the heterogeneous Fenton-like process. In this study, nanocomposites of Fe3O4 anchored onto reduced graphene oxide (RGO) were prepared by a moderate alkaline-thermal precipitation method and developed as highly efficient heterogeneous Fenton-like catalysts. The characterization results indicated that Fe3O4 nanoparticles (NPs) were tightly anchored onto few-layer RGO sheets via a strong interaction. Contrast experiments showed that Fe3O4/RGO nanocomposites had much better Fenton-like catalytic activity than Fe3O4 NPs. The process optimization of methyl orange (MO) discoloration in Fe3O4/RGO-H2O2 system was accomplished by central composite design under response surface methodology. A second-order polynomial model was established to predict the optimal values of MO discoloration and its significance was evaluated by analysis of variance. Three-dimensional response surfaces for the interaction between two variables were constructed. Based on the model prediction, the optimum conditions for MO discoloration in Fe3O4/RGO-H2O2 system were 2.9 for solution pH, 16.5 mM H2O2 concentration, 2.5 g/L catalyst dosage and 33.5 min of reaction time, with the maximum predicted value for MO discoloration ratio of 99.98%.


Assuntos
Compostos Azo/química , Grafite/química , Modelos Químicos , Nanopartículas/química , Poluentes Químicos da Água/química , Catálise , Cor , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Ferro/química , Microscopia Eletrônica de Transmissão , Óxidos/química , Análise Espectral Raman , Difração de Raios X
5.
Water Sci Technol ; 74(10): 2417-2426, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27858798

RESUMO

Due to the difficult separation of superfine schorl powder (SSP) from solution after being used, millimetre-scale porous schorl ceramisite (PSC) was obtained through solid-phase sintering method and used as a heterogeneous catalyst for Fenton-like discoloration of organic dyes. SSP and PSC were characterized by X-ray diffraction, Fourier transform infrared spectroscopy and field emission scanning electron microscopy. The results demonstrated that both SSP and PSC were mainly composed of schorl and there existed large amounts of micropores on the surface of PSC. A series of control experiments indicated that PSC exhibited higher Fenton-like catalytic activity than SSP. Methylene blue (MB) discoloration in both PSC-H2O2 and SSP-H2O2 systems followed pseudo-first-order kinetics and the reaction rate constant k1 obtained in PSC-H2O2 system was 3.23 times as large as the one in SSP-H2O2 system. Then, the process optimization of MB discoloration in heterogeneous Fenton-like reaction catalyzed by PSC was operated by central composite design under response surface methodology. Based on the model prediction, the optimum conditions for MB discoloration in this system were determined.


Assuntos
Corantes/química , Peróxido de Hidrogênio/química , Azul de Metileno/química , Silicatos/química , Poluentes Químicos da Água/química , Catálise , Cinética , Porosidade , Purificação da Água/métodos , Difração de Raios X
6.
PLoS One ; 10(11): e0142616, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26565712

RESUMO

Graphitic carbon nitride (g-C3N4) used in this work was obtained by heating dicyandiamide and melamine, respectively, at different temperatures. The differences of g-C3N4 derived from different precursors in phase composition, functional group, surface morphology, microstructure, surface property, band gap and specific surface area were investigated by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, UV-visible diffuse reflection spectroscopy and BET surface area analyzer, respectively. The photocatalytic discoloration of an active cationic dye, Methylene Blue (MB) under visible-light irradiation indicated that g-C3N4 derived from melamine at 500°C (CN-M500) had higher adsorption capacity and better photocatalytic activity than that from dicyandiamide at 500°C (CN-D500), which was attributed to the larger surface area of CN-M500. MB discoloration ratio over CN-M500 was affected by initial MB concentration and photocatalyst dosage. After 120 min reaction time, the blue color of MB solution disappeared completely. Subsequently, based on the measurement of the surface Zeta potentials of CN-M500 at different pHs, an active anionic dye, Methyl Orange (MO) was selected as the contrastive target pollutant with MB to reveal the synergic effect between adsorption and photocatalysis. Finally, the photocatalytic mechanism was discussed.


Assuntos
Poluentes Ambientais/isolamento & purificação , Grafite/química , Azul de Metileno/isolamento & purificação , Nitrilas/química , Fotólise , Adsorção , Catálise , Guanidinas/química , Triazinas/química
7.
Environ Sci Pollut Res Int ; 21(2): 1582-91, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23943082

RESUMO

The anatase/schorl composites were prepared and employed for the photocatalytic discoloration of an azo dye, Methyl Orange (MO). X-ray diffraction results indicated that TiO2 existed in the form of anatase phase and no diffraction peaks of schorl could be observed for all the composite samples. Scanning electron micrographs showed that the particles of anatase were well deposited and dispersed on the surface of schorl. Photocatalytic experiments revealed that the anatase/schorl composites exhibited higher photocatalytic activity for MO discoloration than pure TiO2 and more than 90% discoloration ratio could be obtained within 60 min UV irradiation when the sample containing 3 wt.% of schorl as TiO2 support was used. Then, the central composite design (CCD) under the response surface methodology (RSM) was employed for the experiment design and process optimization. The significance of a second-order polynomial model for predicting the optimal values of MO discoloration was evaluated by the analysis of variance (ANOVA) and 3D response surface plots for the interactions between two variables were constructed. Based on the model prediction, the optimum conditions for the photocatalytic discoloration of MO by TiO2/schorl composite were determined to be 15 × 10(-3) mM MO initial concentration, 2.7 g/l photocatalyst dosage, solution pH 6.6 and 43 min reaction time, with a maximum MO discoloration ratio of 98.6%. Finally, a discoloration ratio of 94.3% was achieved for the real sample under the optimum conditions, which was very close to the predicted value, implying that RSM is a powerful and satisfactory strategy for the process optimization.


Assuntos
Compostos Azo/química , Corantes/química , Processos Fotoquímicos , Silicatos/química , Titânio/química , Poluentes Químicos da Água/química , Compostos Azo/análise , Catálise , Corantes/análise , Indústria Têxtil , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Difração de Raios X
8.
Environ Sci Pollut Res Int ; 20(8): 5764-72, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23463277

RESUMO

A cationic dye, Rhodamine B (RhB), could be efficiently discolored by heterogeneous Fenton-like reaction catalyzed by natural schorl. In this work, with the main goal of the optimization for RhB discoloration, central composite design under the response surface methodology (RSM) was employed for the experiment design and process optimization. The significance of a second-order polynomial model for predicting the optimal values of RhB discoloration was evaluated by the analysis of variance and 3D response surface and counter plots for the interactions between two variables were constructed. The Pareto graphic analysis of the discoloration process indicated that, among all the variables, solution pH (X 3, 47.95 %) and H2O2 concentration (X 1, 24.39 %) had the largest influences on the heterogeneous Fenton-like discoloration of RhB. Based on the model prediction, the optimum conditions for RhB discoloration were determined to be 45 mM H2O2 concentration, 2.5 g/L schorl dosage, solution pH 2, and 110 min reaction time, with the maximum RhB discoloration ratio of 98.86 %. The corresponding experimental value of RhB discoloration ratio under the optimum conditions was determined as 99.31 %, which is very close to the optimized one, implying that RSM is a powerful and satisfactory strategy for the process optimization.


Assuntos
Corantes/química , Peróxido de Hidrogênio/química , Oxidantes/química , Rodaminas/química , Silicatos/química , Poluentes Químicos da Água/química , Catálise , Cor , Concentração de Íons de Hidrogênio , Modelos Químicos , Análise de Regressão , Fatores de Tempo , Eliminação de Resíduos Líquidos/métodos
9.
J Environ Sci (China) ; 17(2): 232-6, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16295895

RESUMO

Picea mongolica W. D. Xu. is an endemic species in China. The spruce forest is only found in semi-arid habitat in Inner Mongolia Autonomous Region of China. Based on the simulative defoliation experiment, it was proved that Picea mongolica seedlings had the compensatory and overcompensatory effects under the certain defoliation rate. The results of variance analysis on growth indexes showed that in PM I (natural regeneration seedlings under Picea mongolica forest), the differences of H1 (height in June 23) and H2 (height in September 3) were extremely significant, and the difference of D(diameter at the breast height) were not significant. In PM II (artificial regeneration seedlings under Betula platyphylla Suk. forest), the difference of H1 was significant, the difference of H2 was not significant, and the difference of D was extremely significant. The regression equations were established and the compensatory and overcompensatory points were obtained. In PM I, the compensatory points of H1, H2, and D were 0.7628, 0.7436, 0.5725, and the overcompensatory points were 0.6056, 0.5802 and 0.2909 respectively. In PM II, the compensatory points of H,, H2, and D are 0.5012, 0.3421, 0.2488, and the overcompensatory points are 0.4137, 0.2633 and 0.0747 respectively. These results suggested that the induction of compensatory growth mechanisms in spruce seedlings required a threshold level of defoliation, and the insects in Picea mongolica forest could be controlled in a certain degree.


Assuntos
Picea/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Plântula/crescimento & desenvolvimento , Análise de Variância , China , Regressão Psicológica
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