Biosorption and bioreduction of Cr (VI) by rice husk and toxicity analysis on zebrafish embryos

In this paper, acute and subacute toxicity effects of on an environmental estrogen, Bisphenol A (BPA), on zebrafish were investigated. The median lethal concentration (LC50) and the median effect concentration (EC50) of BPA to zebrafish embryos and larvae were calculated. Additionally, effects of BPA on vitellogenin (VTG) gene expression and mating ability to adult male zebrafish were investigated for subacute toxicity analysis. Differed from previous studies on toxicity of BPA, acetone, a relative low-level toxic solution, was adopted as the carrier solvent of BPA in this study. Results showed that the values of 24h、48h and 72h LC50 of BPA on zebrafish embryos and larvae were 16.667mg/l, 9.944 mg/ l, 8.222 mg/l and 20.938 mg/l, 15.170 mg/l, 10.943 mg/l, respectively. The values of 24h and 48h EC50 of BPA on zebrafish embryos were 11.111mg/l and 8.183mg/l, while the valuSubscript textes of 24h, 48h and 72h EC50 of BPA on zebrafish larvae were 14.56mg/l, 12.133mg/l and 9.658mg/l, respectively. Subacute toxicity analysis demonstrated VTG gene was induced in male zebrafish by BPA and the increasing of its expression was both time- and dose-dependent. In addition, BPA could severely inhibit the mating ability of adult male zebrafish and a positive relevance was found between the inhibition and the concentration of BPA exposed.

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Mapping of accumulation of SeNPs in developing zebrafish embryos and larvae: a new method using SEM with energy dispersive X‐ray spectrometer

Micro & Nano Letters ◽

10.1049/mnl.2016.0692 ◽

2017 ◽

Vol 12 (7) ◽

pp. 497-499

Author(s):

Kalimuthu Kalishwaralal ◽

Subhaschandrabose Jeyabharathi ◽

Krishnan Sundar ◽

Azhaguchamy Muthukumaran

Keyword(s):

Energy Dispersive ◽

New Method ◽

Zebrafish Embryos ◽

X Ray

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Mechanoactivation Of Rice Husk Ash In Laboratory Conditions

Promyshlennoe i Grazhdanskoe Stroitel stvo ◽

10.33622/0869-7019.2019.11.20-26 ◽

2019 ◽

pp. 20-26

Keyword(s):

Mechanical Activation ◽

Rice Husk ◽

Amorphous Silica ◽

Silicon Oxide ◽

Rice Husk Ash ◽

Pozzolanic Activity ◽

Maximum Solubility ◽

Laboratory Conditions ◽

Before And After ◽

Mineral Additive

In many rice producing countries of the world, including in Vietnam, various research aimed at using rice husk ash (RHA) as a finely dispersed active mineral additive in cements, concrete and mortars are being conducted. The effect of the duration of the mechanoactivation of the RHA, produced under laboratory conditions in Vietnam, on its pozzolanic activity were investigated in this study. The composition of ash was investigated by laser granulometry and the values of indicators characterizing the dispersion of its particles before and after mechanical activation were established. The content of soluble amorphous silicon oxide in rice husk ash samples was determined by photocolorimetric analysis. The pizzolanic activity of the RHA, fly ash and the silica fume was also compared according to the method of absorption of the solution of the active mineral additive. It is established that the duration of the mechanical activation of rice husk ash by grinding in a vibratory mill is optimal for increasing its pozzolanic activity, since it simultaneously results in the production of the most dispersed ash particles with the highest specific surface area and maximum solubility of the amorphous silica contained in it. Longer grinding does not lead to further reduction in the size of ash particles, which can be explained by their aggregation, and also reduces the solubility of amorphous silica in an aqueous alkaline medium.

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