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1.
RSC Adv ; 13(6): 3958-3970, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36756548

RESUMO

The Fe-Ce bimetal oxide-doped titanium dioxide composite was synthesized by the sol-gel method and the performance of the catalyst was investigated for the removal of Hg0 and AsH3 from yellow phosphorus flue gas under different conditions. Brunauer-Emmett-Teller (BET) analysis, high-resolution transmission electron microscopy (HR-TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) were used to characterize the crystal structure and morphology of the structure, and the mechanisms for removing Hg0 and AsH3 from flue gas by catalytic oxidation were deduced. The results showed that the optimal calcination temperature of the Fe5Ce5Ti catalyst was 500 °C, and the optimal pH of the sol was 6. Under these conditions, the penetration adsorption capacity of the Fe5Ce5Ti catalyst for the removal of AsH3 and Hg0 was 385.5 mg g-1 and 2.178 mg g-1, respectively. According to characterization analysis, Fe and Ce are the main active components in the removal of Hg0 and AsH3, and the mixed oxides of Fe and Ce have a synergistic effect on the surface of the mixed oxide-doped catalyst, which can improve the dispersion of the active component on the surface of the catalyst, and then improve the removal efficiency of Hg0 and AsH3.

2.
Animals (Basel) ; 13(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36670806

RESUMO

The effects of four different-sized cages­huge (HC), large (LC), medium (MC), and small (SC) cages­on the productive performance, serum biochemical indices, and caecal microbiota composition of Roman laying hens were investigated. At 44 weeks of age, a total of 450 hens were selected and allocated to the four groups, with six replicates each. Equal stocking density (0.054 m2 per bird) was maintained among the four groups throughout the experiment, and number of birds/cage changed for each treatment. After 2 weeks of preliminary trial, the formal experiment was performed from 46 to 60 weeks of age. The laying rate and feed conversion ratio (FCR) were determined daily, antibody titres were measured every 3 weeks, and serum biochemical parameters and caecal microbiota composition were analysed at 60 weeks of age. Compared to HC and SC, the higher laying rate and lower FCR in MC and LC indicated positive effects on egg production and feed efficiency, while SC showed the highest body weight gain (p < 0.05). With increasing cage size, the serum triglycerides (TG) and total cholesterol (T-CH) levels were reduced, and serum glutathione peroxidase (GSH-Px) activity improved, where birds raised in HCs had the lowest serum TG and T-CH and the highest GSH-Px activity. Twenty-nine different phyla and 301 different genera were detected in the caecal microbiota of birds in the four groups. Methanobrevibacter was significantly higher in the SC than in the other groups (p < 0.05). Faecalibacterium was most abundant in the MC compared with the other groups (p < 0.05) and was significantly positively correlated with serum GSH-Px concentration (R = 0.214, p = 0.0017). Lactobacillus was significantly less abundant in the LC and MC than in the HC and SC groups (p < 0.05) and was significantly positively correlated with body weight (R = 0.350, p = 0.0009) but negatively correlated with laying rate and FCR. In conclusion, MC were superior to HC and LC in improving feed conversion efficiency and caecal microflora composition compared to the SC. An appropriate increase in cage size is beneficial to laying hen production and health.

3.
Polymers (Basel) ; 14(15)2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35956594

RESUMO

The selection of optimal process parameters has a decisive effect on the quality of 3D printing. In this work, the numerical and experimental methods were employed to investigate the FDM printing deposition process of PLA/GNPs nanocomposite. The effect of process parameters on cross-sectional morphology and dimension of the deposited filament, as well as the mechanical property of the FDM printed specimens were studied. The extrusion and the deposition process of the molten PLA/GNPs nanocomposite was simulated as a fluid flow by the paradigm of CFD, the effects of printing temperature and shear rate on thermal-physical properties, such as viscosity and surface tension, were considered in models. Under the assumptions of non-Newtonian fluid and creep laminar flow, the deposition flow was controlled by two key parameters: the nozzle temperature and the nozzle velocity. The numerical model was verified by experiments from four aspects of thickness, width, area, and compactness of the deposited PLA/GNPs nanocomposite filament cross-section. Both the numerical simulation and experiment results show that with the increase of nozzle temperature and nozzle velocity, the thickness, area, and compactness of the deposited filament decreases. While the width of deposited filament increased with the increase of nozzle temperature and decrease of nozzle velocity. The decrease in thickness and the increase in width caused by the change of process parameters reached 10.5% and 24.7%, respectively. The tensile strength of the printed PLA/GNPs specimen was about 61.8 MPa under the higher nozzle temperatures and velocity condition, an improvement of 18.6% compared to specimen with the tensile strength of 52.1 MPa under the lower nozzle temperatures and velocity condition. In addition, the experimental results indicated that under the low nozzle velocity and nozzle temperature condition, dimensional standard deviation of the printed specimens decreased by 52.2%, 62.7%, and 68.3% in X, Y, and Z direction, respectively.

4.
Sci Rep ; 11(1): 19169, 2021 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-34580331

RESUMO

Water quality is critical for egg production and animal health in commercial layer housing systems. To investigate microbial contamination in nipple drinking system in layer houses, the bacterial abundance and communities in water pipes and V-troughs on different tiers (e.g., 1st, 3rd, 5th, and 7th tiers) of a layer house with 8 overlapping cage tiers were determined using qRT-PCR and 16S rRNA sequencing. The water bacterial abundance (i.e., genome 16S rDNA copy number, WBCN) in water pipes and V-troughs did not significantly differ among tiers, but they were 46.77 to 1905.46 times higher in V-troughs than that in water pipes (P < 0.05) for each tier. Illumina sequencing obtained 1,746,303 effective reads from 24 water samples in V-troughs of 4 tiers (six samples from each tier). Taxonomic analysis indicated that the 1st and 5th tiers were predominated by Proteobacteria, Actinobacteria, Firmicutes and Bacteroidetes, while the 3rd and 7th tiers were predominated by Proteobacteria, Firmicutes, Bacteroidetes and Actinobacteria. The top four genera were Acinetobacter, Streptococcus, Rothia and Comamonas among measured tiers. The high bacterial abundance and bacterial OTUs of water in the V-troughs reflect poor water quality, which may adversely affect growth and health of laying hens. Therefore, it is suggested that water quality in the V-tough should be checked more frequently in commercial layer houses.


Assuntos
Bactérias/isolamento & purificação , Água Potável/microbiologia , Animais , Bactérias/genética , Galinhas , Abrigo para Animais , RNA Ribossômico 16S , Reação em Cadeia da Polimerase em Tempo Real , Microbiologia da Água , Qualidade da Água
5.
J Ethnopharmacol ; 211: 348-357, 2018 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-28986333

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Danhong Injection (DHI) and Naoxintong Capsule (NXT) are renowned traditional Chinese medicine in China. The drug combination of DHI and NXT is frequently applied for the treatment of cardiovascular and cerebrovascular diseases in clinic. However, there had been no pharmacological experiment studies of interaction between DHI and NXT. Due to the drug interactions, exploring their interaction profile is of great importance. MATERIAL AND METHODS: In this study, focal cerebral I/R injury in adult male Sprague-Dawley rats were induced by transient middle cerebral artery occlusion (tMCAO) for 1h followed by reperfusion. Rats were divided into 5 groups: sham group, ischemia reperfusion untreated group (IRU), DHI group (DHI 10mL/kg/d), NXT group (NXT 0.5g/kg/d), DHI plus NXT group (DHI-NXT, DHI 10mL/kg/d plus NXT 0.5g/kg/d). All drug-treated groups were respectively successive administrated for 7 days after ischemia/ reperfusion (I/R) injury. The effects on rat neurological function were estimated by neurological defect scores. Brain infarct volumes were determined based on 2, 3, 5-triphenyltetrazolium chloride (TTC) staining. Pathological changes in brain tissues were observed using hematoxylin and eosin (H&E) staining and transmission electron microscope (TEM). Levels of nitric oxide (NO), granulocyte colony-stimulating factor (G-CSF) and granulocyte macrophage colony-stimulating factor (GM-CSF) in serum were determined with enzyme-linked immunosorbent assay (ELISA). Immunohisto-chemistry and Western blot were used to detect the expressions of basic fibroblast growth factor (bFGF), von Willebrand factor-microvessel vascular density (vWF-MVD), vascular endothelial cell growth factor (VEGF), transforming growth factor-ß1 (TGF-ß1), angiogenin-1 (Ang-1), angiogenin-2 (Ang-2) and platelet derived growth factor (PDGF) at day 7 after ischemia/reperfusion (I/R) injury. RESULTS: Compared with IRU group and mono-therapy group (DHI group or NXT group), Danhong Injection combined with Naoxintong Capsule (DHI-NXT) group significantly ameliorated neurological deficits scores, infarct volume and pathological change, significantly decreased the overexpression of NO and the level of Ang-1, significantly increased the expressions of VEGF, Ang-2, G-CSF, GM-CSF, bFGF, PDGF, vWF, TGF-ß1. CONCLUSION: The protective benefits on rat brain against I/R injury were clearly produced when DHI and NXT were used in combination, which provided rational guidance for clinical combined application of DHI and NXT, and this protection maybe associated with the up-regulation expressions of the related chemokines and growth factors of angiogenesis.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Infarto da Artéria Cerebral Média/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Quimioterapia Combinada , Medicamentos de Ervas Chinesas/farmacologia , Fator 2 de Crescimento de Fibroblastos/metabolismo , Fator Estimulador de Colônias de Granulócitos/sangue , Fator Estimulador de Colônias de Granulócitos e Macrófagos/sangue , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/patologia , Masculino , Fármacos Neuroprotetores/farmacologia , Óxido Nítrico/sangue , Fitoterapia , Fator de Crescimento Derivado de Plaquetas/metabolismo , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo
6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(5): 1389-95, 2016 May.
Artigo em Chinês | MEDLINE | ID: mdl-30001012

RESUMO

The UV-B radiation on the surface of our planet has been enhanced due to gradual thinning of ozone layer. The change of solar spectrum UV-B radiation will cause damage to all kinds of terrestrial plants at certain degree. In this paper, taking breeding sorghum (Sorghum bicolor (L.Moench))variety Longza No.5 as sample, 40 µW·cm-2 UV-B radiation treatment was conducted on sorghum seedlings at two-leaf and one-heart stage and different time courses; then after a 2 d recovering, photosynthetic parameters were measured with a photosynthetic apparatus; the activities of antioxidant enzymes were detected as well. Our results revealed that, as the dosages of UV-B increasing, leaf browning injury was aggravated, plants dwarfing and significantly were reduced fresh weight and dry weight were observed; anthocyanin content was significantly increased; chlorophyll and carotenoid content significantly were reduced and net photosynthetic rate and chlorophyll fluorescence parameters were decreased. Meanwhile, with the increase in UV-B dosages, stomatal conductance, intercellular CO2 concentration and transpiration rate showed "down - up - down" trend; the activities of SOD and GR presented "down - up" changes; activities of POD and CAT demonstrated "down - up - down", and APX, GPX showed an "up - down - up" pattern. It is worth to note that, under the four-dose treatment, a sharp decline in net photosynthesis in sorghum seedlings was observed at 6 h UV-B treatment (equals to 2.4 J·m-2), and an obvious turning point was also found for other photosynthetic parameters and activities of antioxidant enzymes at the same time point. In summary, the results indicated that the enhanced UV-B radiation directly accounted for the damages in photosynthesis system including photosynthetic pigment content, net photosynthetic rate and chlorophyll fluorescence parameters of sorghum; the antioxidant system showed different responses to UV-B radiation below or above 6 h treatment: ASA-GSH cycle was more sensitive to low-dose UV-B radiation, while high-dose UV-B radiation not only undermined the photosynthesis system, but also triggered plant enzymatic and non-enzymatic antioxidant systems, resulting in leaf browning and necrosis,biomass accumulation reduction, plant dwarfing and even death.


Assuntos
Sorghum , Antioxidantes , Biomassa , Clorofila , Fotossíntese , Folhas de Planta , Plântula , Raios Ultravioleta
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