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Experimental and theoretical studies have been conducted to investigate the adsorption of atrazine in aqueous solutions by sheep manure-derived biochar synthesized at 650°C (SMB650). The results of characterization analysis showed that SMB650 possessed large specific surface area and was rich in pore structure and functional groups. The removal efficiency of atrazine by SMB650 was 95.3% under the optimum conditions, of which contact time, initial atrzaine concentration, initial solution pH, SMB650 dosage and temperature were 150 min, 1500 μg/L, 3.0, 1.6 g/L and 25ºC, respectively. The results of kinetic and isotherm studies revealed that the pseudo second-order and the Freundlich model fit the experimental data best (R2>0.98). The adsorption of atrazine onto SMB650 belonged to multi-molecular layer adsorption. The calculated thermodynamic parameters like free energy change (ΔGθ), enthalpy change (ΔHθ) and entropy change (ΔSθ) were -7.8730 to -6.2976 kJ/mol, 17.2179 kJ/mol and 0.0788 kJ/(mol·K), respectively, indicating that the adsorption process of atrazine onto SMB650 was spontaneous, endothermic and entropy-increased. The present study showed that the sheep manure-derived biochar could be used as a promising adsorbent for the removal of atrazine from aqueous solutions.
The aim of the study was to describe the effects of acetate on hypothalamic G-protein-coupled receptor (GPR) 41 or 43, 5’-AMP-activated protein kinase (AMPK) signalling, mitogen-activated protein kinases (MAPKs) signalling and (an)orexigenic neuropeptides. Forty rabbits (Hyla, 35-day old) were randomly assigned to one of two treatment groups: intravenous injection of acetate (0.5 mg · kg−1 body weight) or vehicle (control). The acetate treatment decreased the rabbit feed intake within 5 h as compared with the control (P < 0.05). Although the acetate treatment had no effect on hypothalamic neuropeptide Y, agouti-related protein, cocaine-amphetamine-regulated transcript, GPR41, acetyl-CoA carboxylase, fatty acid synthase and carnitine palmitoyltransferase-1 mRNA levels (P > 0.05), it significantly increased the gene expression of the pro-opiomelanocortin (POMC) and GPR43 (P < 0.05). Moreover, intravenous injection of acetate did not affect the protein levels of phosphorylated extracellular signal-regulated kinases, AMPK or p38 MAPK in comparison with the control group (P > 0.05); however, there was a significant increase in GPR43 protein level and decrease in phosphorylated c-Jun N-terminal kinases (JNK) level (P < 0.05). So, acetate induced anorexia via the up-regulation of hypothalamic POMC gene expression, which may be associated with membrane GPR43 and intracellular JNK signalling.
The degradation of atrazine (ATZ) by ultraviolet/peroxymonosulfate (UV/PMS) under different conditions was investigated in phosphate buffer, and the degradation mechanism and kinetics were discussed. The results showed that the degradation rate of 2.5 μmol/L ATZ in UV/PMS system was 97.63% in 20 min when the reaction temperature was 20ºC, the concentration of PMS was 20 μmol/L and the UV intensity was 50 mW/cm2 in pH7 phosphate buffer. The mechanism analysis showed that PB with partial alkalinity promoted the degradation of ATZ by UV/PMS more than that with acidic PB. The effect of PB with alkaline conditions on the degradation of ATZ by UV/PMS was more complicated and mainly related to the state of phosphate ions. The UV/PMS system contained both HO• and SO4-•, and the ratio of HO•, SO4-•and UV-degraded ATZ was nearly 1:1 in pH7 PB. Inorganic anions experiments showed that Cl- and HCO3- inhibited the degradation of ATZ under UV/PMS, and the inhibitory effect of Cl- was more obvious. NO3- promoted the degradation of ATZ by UV/PMS. Kinetic analysis showed that UV/PMS degradation of ATZ reaction kinetics was more in line with the quasi first-order reaction kinetics, the inhibition effect of the same concentration of ETA and Clon UV/PMS degradation of ATZ are the same, and UV/PMS degradation of ATZ decreased by 38.54% and 36.29% respectively. The addition of NO3- increased the rate of degradation of ATZ by UV/PMS by 31.21%. By LC-MS analysis, 5 kinds of production m/z and 6 kinds of products were obtained.
Dysosma versipellis (Hance) M. Cheng is an endangered plant due to overharvesting for the extraction of podophyllotoxin. Thus, the in vitro technique is valuable for the propagation of this species. When the explants of rhizome buds were cultured on Murashige and Skoog’s (MS) medium with 6-benzyladenine (BA) (1.0 mg l⁻¹), gibberellic acid (GA₃) (0.5 mg l⁻¹) and zeatin (Zea) (0.5 mg l⁻¹), multiple buds were regenerated directly on the explants without callusing within 6 weeks. Callus was induced from the leaf segment cultures on MS basal medium supplemented with 2,4-dichlorophenoxyacetic acid (2,4-D) (0.5 mg l⁻¹) and BA (0.2 mg l⁻¹) within 4 weeks. The adventitious buds were differentiated when the calli were subcultured on MS medium supplemented with BA (1.0 mg l⁻¹) and thidiazuron (TDZ) (0.2 mg l⁻¹) within 6 weeks. The adventitious buds obtained from callus and the rhizome-buds rooted with a frequency of 100% on half strength MS medium fortified with indole-3-butyric acid (IBA) 0.5 mg l⁻¹ and activated charcoal (AC) 0.5 g l⁻¹ for 4 weeks. The rooted shoots were successfully transplanted from a mixture of vermiculite:soil (1:1 v/v) to the field with a survival rate of 85%. Podophyllotoxin production in calli, cultured rhizomes, rhizomes of transplanting plants from the garden and rhizomes in the wild field was confirmed by high-performance liquid chromatography (HPLC) analysis. Our results suggest that calli, cultured rhizomes and rhizomes of transplanting plants would be the potential sources of podophyllotoxin.
Pelage color variants have been documented in some small mammals, but there is not any reported about coat color variation in shrews. Here, pelage color variants of the two sibling species (Sorex cylindricauda and Sorex bedfordiae) were uncovered in different sampling sites. Our data may initiate new interest to pelage color variants in small mammals. Furthermore, the classification of two striped shrews has been controversial for several decades. We conducted a detailed examination of the morphometric characters for the two sibling shrews. Significant differences between the two species morphologically confirmed the two-species classification status.
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