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Tatsuya Ueki - One of the best experts on this subject based on the ideXlab platform.
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Mechanism of Vanadium accumulation and possible function of Vanadium in underwater adhesion in ascidians
INTERNATIONAL CONFERENCE ON BIOLOGY AND APPLIED SCIENCE (ICOBAS), 2019Co-Authors: Tatsuya Ueki, Tri Kustono AdiAbstract:Ascidians are marine animals that belong to the same phylogenetic group (Phylum Chordata) as human beings do. One of the three suborders in ascidians can accumulate a high level of Vanadium ions in blood cells. Ascidia gemmata has been reported to accumulate the highest levels of Vanadium at 350 mM, which is 107-fold higher than the Vanadium concentration in seawater. In the last two decades, many genes and proteins related to Vanadium accumulation and reduction have been revealed by molecular biological and biochemical methods. Modern omics approach enhanced the comprehensive identification of factors related to this phenomenon. In this review article, first, we would like to summarize the history of studies on Vanadium accumulation in ascidians briefly. Then, we would like to overview recent advances by omics studies. How ascidians selectively accumulate Vanadium is discussed from biochemical properties of proteins responsible for each step, and why ascidians accumulate Vanadium is discussed in relation to the underwater adhesion.Ascidians are marine animals that belong to the same phylogenetic group (Phylum Chordata) as human beings do. One of the three suborders in ascidians can accumulate a high level of Vanadium ions in blood cells. Ascidia gemmata has been reported to accumulate the highest levels of Vanadium at 350 mM, which is 107-fold higher than the Vanadium concentration in seawater. In the last two decades, many genes and proteins related to Vanadium accumulation and reduction have been revealed by molecular biological and biochemical methods. Modern omics approach enhanced the comprehensive identification of factors related to this phenomenon. In this review article, first, we would like to summarize the history of studies on Vanadium accumulation in ascidians briefly. Then, we would like to overview recent advances by omics studies. How ascidians selectively accumulate Vanadium is discussed from biochemical properties of proteins responsible for each step, and why ascidians accumulate Vanadium is discussed in relation...
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Bioaccumulation of Vanadium by Vanadium-Resistant Bacteria Isolated from the Intestine of Ascidia sydneiensis samea
Marine Biotechnology, 2016Co-Authors: Tatsuya UekiAbstract:Isolation of naturally occurring bacterial strains from metal-rich environments has gained popularity due to the growing need for bioremediation technologies. In this study, we found that the Vanadium concentration in the intestine of the Vanadium-rich ascidian Ascidia sydneiensis samea could reach 0.67 mM, and thus, we isolated Vanadium-resistant bacteria from the intestinal contents and determined the ability of each bacterial strain to accumulate Vanadium and other heavy metals. Nine strains of Vanadium-resistant bacteria were successfully isolated, of which two strains, V-RA-4 and S-RA-6, accumulated Vanadium at a higher rate than did the other strains. The maximum Vanadium absorption by these bacteria was achieved at pH 3, and intracellular accumulation was the predominant mechanism. Each strain strongly accumulated copper and cobalt ions, but accumulation of nickel and molybdate ions was relatively low. These bacterial strains can be applied to protocols for bioremediation of Vanadium and heavy metal toxicity.
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Vanadium in the Environment and Its Bioremediation
Plants Pollutants and Remediation, 2015Co-Authors: Tatsuya UekiAbstract:Vanadium is an element with symbol V and atomic number 23. The vast majority of Vanadium demand is from the steel industry, and the rest for titanium alloy and catalyst in chemical factory. Air pollution and water pollution by Vanadium were recognized from early twentieth century. Increasing information on the toxicity and medicinal use enhanced the development of bioremediation of Vanadium. In this chapter, the author would like to overview the history of pollution of Vanadium, Vanadium toxicity, bioaccumulation and bioremediation of Vanadium.
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High Levels of Vanadium in Ascidians
Vanadium, 2011Co-Authors: Hitoshi Michibata, Tatsuya UekiAbstract:Henze’s discovery of high levels of Vanadium in an ascidian was not only a trigger for research in Vanadium science, but also aroused great interest in the question of how such extraordinarily high levels of Vanadium could be accumulated and what the role of Vanadium in ascidians could possibly be. Many investigators, including inorganic, catalytic, and applied chemists, as well as physiological, molecular, and pharmaceutical biologists have been involved in this interdisciplinary problem. In this review, we not only trace the history of Vanadium research, but also describe recent advances in our understanding of the field from several viewpoints: the determination of high levels of Vanadium, the identification of Vanadium-accumulating blood cells, the energetics of Vanadium accumulation, the sulfate transport system, the redox mechanism of Vanadium, and the possible physiological roles of Vanadium in ascidians.
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Reduction of Vanadium(V) to Vanadium(IV) by NADPH, and Vanadium(IV) to Vanadium(III) by cysteine methyl ester in the presence of biologically relevant ligands.
Biochimica et biophysica acta, 2007Co-Authors: Mohammad K. Islam, Chieko Tsuboya, Hiroko Kusaka, Sen-ichi Aizawa, Tatsuya Ueki, Hitoshi Michibata, Kan KanamoriAbstract:To better understand the mechanism of Vanadium reduction in ascidians, we examined the reduction of Vanadium(V) to Vanadium(IV) by NADPH and the reduction of Vanadium(IV) to Vanadium(III) by L-cysteine methyl ester (CysME). UV-vis and electron paramagnetic resonance spectroscopic studies indicated that in the presence of several biologically relevant ligands Vanadium(V) and Vanadium(IV) were reduced by NADPH and CysME, respectively. Specifically, NADPH directly reduced Vanadium(V) to Vanadium(IV) with the assistance of ligands that have a formation constant with Vanadium(IV) of greater than 7. Also, glycylhistidine and glycylaspartic acid were found to assist the reduction of Vanadium(IV) to Vanadium(III) by CysME.
Dongmei Luo - One of the best experts on this subject based on the ideXlab platform.
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Direct recovery of low valence Vanadium from Vanadium slag —— Effect of roasting on Vanadium leaching
Hydrometallurgy, 2020Co-Authors: Zhenghao Wang, Guoquan Zhang, Liang Chen, Tahani Aldahrib, Weizao Liu, Yuhao Yang, Dongmei LuoAbstract:Abstract Traditional Vanadium products recovered from Vanadium slag, such as alloys or battery electrolytes, are manufactured by oxidizing the Vanadium to a high valence state (V(V)) and then reducing it to a low valence state again. This process consumes significant energy and raw materials and generates toxic waste water and residue laden with V(V). In this paper, an economic and energy-efficient method to directly extract low valence Vanadium (LVV) from Vanadium slag without producing poisonous waste is proposed for the first time. The structure of the Vanadium spinel in the slag was broken by roasting in an O2 and N2 atmosphere allowing the low valence Vanadium to be leached. Different roasting conditions were studied for their effect on the resulting extraction ratio, showing that after roasting and leaching, low valence Vanadium ions in solution accounted for all of the leached Vanadium, with an extraction ratio of 69.37%. The products of the roasting process were analyzed by thermal gravimetry, X-ray diffraction, scanning electron microscopy, and X-ray photoelectron spectroscopy. In the Vanadium spinels, Fe(II) was oxidized to Fe(III) and V(III) to V(IV), breaking the spinel structure and causing the LVV to leach from the Vanadium slag.
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simultaneous extraction of Vanadium and titanium from Vanadium slag using ammonium sulfate roasting leaching process
Journal of Alloys and Compounds, 2018Co-Authors: Guoquan Zhang, Dongmei Luo, Chenhui Deng, Bin LiangAbstract:Abstract Sodium and calcification roasting processes are traditional technologies to recover Vanadium from Vanadium slag. However, these processes are associated with many drawbacks, including high energy consumption, serious environment pollution, and the inability to simultaneously extract associated titanium resources. In this paper, a novel technology for simultaneous extraction of Vanadium and titanium from Vanadium slag was proposed, in which the Vanadium slag was roasted with recyclable (NH4)2SO4 (AS) at moderately high temperatures followed by dilute H2SO4 leaching. To enhance the extraction, an activation pretreatment of the Vanadium slag through high-temperature water quenching was employed. The results demonstrated that the activation significantly accelerated the extraction, with the Vanadium and titanium extraction increasing by 16% and 12%, respectively, compared with the raw Vanadium slag. The extraction of Vanadium and titanium were 91% and 77%, respectively, after roasting at an AS-to-Vanadium slag mass ratio of 4:1 and 370 °C followed by leaching in a 6% H2SO4 solution. X-ray diffraction analysis indicated that the spinel phases in the Vanadium slag, such as FeV2O4, Fe2TiO3, and Fe2MnO4, began to transform into (NH4)3V(SO4)3, (NH4)3Fe(SO4)3, (NH4)2Mn(SO4)2, and TiSO4 at 320 °C and a nearly complete conversion could be achieved at 370 °C. The mass ratio of AS to Vanadium slag significantly affected the extraction of both Vanadium and titanium, which increased with the increasing mass ratio until an 8:1 ratio was achieved, after which, the extraction decreased. A stratification phenomenon of the Vanadium slag and ammonium bisulfate at high AS/slag mass ratios was observed, which could be responsible for the decreasing extraction.
Jen-how Huang - One of the best experts on this subject based on the ideXlab platform.
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leaching characteristics of Vanadium in mine tailings and soils near a Vanadium titanomagnetite mining site
Journal of Hazardous Materials, 2014Co-Authors: Jinyang Yang, Ya Tang, Evert J. Elzinga, Ashaki A. Rouff, Kai Yang, Jen-how HuangAbstract:A series of column leaching experiments were performed to understand the leaching behaviour and the potential environmental risk of Vanadium in a Panzhihua soil and Vanadium titanomagnetite mine tailings. Results from sequential extraction experiments indicated that the mobility of Vanadium in both the soil and the mine tailings was low, with <1% of the total Vanadium readily mobilised. Column experiments revealed that only <0.1% of Vanadium in the soil and mine tailing was leachable. The Vanadium concentrations in the soil leachates did not vary considerably, but decreased with the leachate volume in the mine tailing leachates. This suggests that there was a smaller pool of leachable Vanadium in the mine tailings compared to that in the soil. Drought and rewetting increased the Vanadium concentrations in the soil and mine tailing leachates from 20 μg L−1 to 50–90 μg L−1, indicating the potential for high Vanadium release following periods of drought. Experiments with soil columns overlain with 4, 8 and 20% volume mine tailings/volume soil exhibited very similar Vanadium leaching behaviour. These results suggest that the transport of Vanadium to the subsurface is controlled primarily by the leaching processes occurring in soils.
Guoquan Zhang - One of the best experts on this subject based on the ideXlab platform.
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Direct recovery of low valence Vanadium from Vanadium slag —— Effect of roasting on Vanadium leaching
Hydrometallurgy, 2020Co-Authors: Zhenghao Wang, Guoquan Zhang, Liang Chen, Tahani Aldahrib, Weizao Liu, Yuhao Yang, Dongmei LuoAbstract:Abstract Traditional Vanadium products recovered from Vanadium slag, such as alloys or battery electrolytes, are manufactured by oxidizing the Vanadium to a high valence state (V(V)) and then reducing it to a low valence state again. This process consumes significant energy and raw materials and generates toxic waste water and residue laden with V(V). In this paper, an economic and energy-efficient method to directly extract low valence Vanadium (LVV) from Vanadium slag without producing poisonous waste is proposed for the first time. The structure of the Vanadium spinel in the slag was broken by roasting in an O2 and N2 atmosphere allowing the low valence Vanadium to be leached. Different roasting conditions were studied for their effect on the resulting extraction ratio, showing that after roasting and leaching, low valence Vanadium ions in solution accounted for all of the leached Vanadium, with an extraction ratio of 69.37%. The products of the roasting process were analyzed by thermal gravimetry, X-ray diffraction, scanning electron microscopy, and X-ray photoelectron spectroscopy. In the Vanadium spinels, Fe(II) was oxidized to Fe(III) and V(III) to V(IV), breaking the spinel structure and causing the LVV to leach from the Vanadium slag.
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simultaneous extraction of Vanadium and titanium from Vanadium slag using ammonium sulfate roasting leaching process
Journal of Alloys and Compounds, 2018Co-Authors: Guoquan Zhang, Dongmei Luo, Chenhui Deng, Bin LiangAbstract:Abstract Sodium and calcification roasting processes are traditional technologies to recover Vanadium from Vanadium slag. However, these processes are associated with many drawbacks, including high energy consumption, serious environment pollution, and the inability to simultaneously extract associated titanium resources. In this paper, a novel technology for simultaneous extraction of Vanadium and titanium from Vanadium slag was proposed, in which the Vanadium slag was roasted with recyclable (NH4)2SO4 (AS) at moderately high temperatures followed by dilute H2SO4 leaching. To enhance the extraction, an activation pretreatment of the Vanadium slag through high-temperature water quenching was employed. The results demonstrated that the activation significantly accelerated the extraction, with the Vanadium and titanium extraction increasing by 16% and 12%, respectively, compared with the raw Vanadium slag. The extraction of Vanadium and titanium were 91% and 77%, respectively, after roasting at an AS-to-Vanadium slag mass ratio of 4:1 and 370 °C followed by leaching in a 6% H2SO4 solution. X-ray diffraction analysis indicated that the spinel phases in the Vanadium slag, such as FeV2O4, Fe2TiO3, and Fe2MnO4, began to transform into (NH4)3V(SO4)3, (NH4)3Fe(SO4)3, (NH4)2Mn(SO4)2, and TiSO4 at 320 °C and a nearly complete conversion could be achieved at 370 °C. The mass ratio of AS to Vanadium slag significantly affected the extraction of both Vanadium and titanium, which increased with the increasing mass ratio until an 8:1 ratio was achieved, after which, the extraction decreased. A stratification phenomenon of the Vanadium slag and ammonium bisulfate at high AS/slag mass ratios was observed, which could be responsible for the decreasing extraction.
Jin-yan Yang - One of the best experts on this subject based on the ideXlab platform.
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Oral bioaccessibility and health risk assessment of Vanadium(IV) and Vanadium(V) in a Vanadium titanomagnetite mining region by a whole digestive system in-vitro method (WDSM)
Chemosphere, 2018Co-Authors: Jin-yan YangAbstract:Oral bioaccessibility of Vanadium(IV) and Vanadium(V) in soil, dust and concentrate fines from a Vanadium titanomagnetite mining region was assessed by a whole digestive system in-vitro scheme. The scheme including the addition of sweat and the large intestinal digestion was used to estimate the oral bioaccessibility of Vanadium(IV) and Vanadium(V) in the whole digestive system for the first time. Higher oral bioaccessibility of Vanadium(IV) and Vanadium(V) was determined in gastric and small intestinal phases demonstrating that their major roles for Vanadium digestion and absorption. The decreasing order of the oral bioaccessibility of Vanadium(IV) and Vanadium(V) in each digestive phase was stomach, small intestine, large intestine and mouth. Higher oral bioaccessibility of Vanadium(V) in the whole digestion indicated its higher risk potential for human than Vanadium(IV). Lower oral bioaccessibility of Vanadium(IV) and Vanadium(V) determined in bionic digestion illustrated detoxicity potential of human body for ingested Vanadium. Compared with soil and dust, higher digestion rate of Vanadium in Vanadium titanomagnetite concentrate fines indicated its higher risk for human, especially for mining workers. Based on Vanadium oral bioaccessibility, hazard quotients of the Vanadium were much less than the critical level suggested for no non-carcinogenic risks to the populations surrounding the sampling sites. Indeed, compared with the estimations based on total Vanadium content, the incorporation of oral Vanadium bioaccessibility into risk assessments could give more realistic information.
