Last edited by Zulkilmaran
Friday, July 10, 2020 | History

3 edition of Reduction of selenite under controlled conditions found in the catalog.

Reduction of selenite under controlled conditions

Yen Thi Hoang Truong

Reduction of selenite under controlled conditions

by Yen Thi Hoang Truong

  • 313 Want to read
  • 11 Currently reading

Published by Laurentian University, School of Graduate Studies in Sudbury, Ont .
Written in English


Edition Notes

Statementby Yen Thi Hoang Truong.
SeriesCanadian theses = Thèses canadiennes
The Physical Object
Paginationx, 74 l. :
Number of Pages74
ID Numbers
Open LibraryOL22233449M
ISBN 100494100133
OCLC/WorldCa175281948

VOL. 54, selenium occurs as selenite. The potential exists to use adapted indigenous bacteria in a treatment system that removes soluble and toxic forms of selenium from water. This may be accomplished by allowing microorganisms to reduce selenate to selenite and precipitated selenium, using chemical treatments to precipitate any remaining selenite, and physically filtering the Cited by: An HCNT1 mutant lacking nitrite reductase grew poorly in the presence of 5 mM selenite, was unable to grow in the presence of 25 or 50 mM selenite and also showed no evidence of selenite reduction.

Under low redox and low pH conditions, sulfur is precipitated while selenium is replaced by selenite and selenide, and at high pH, the reverse is true. The formation of soluble polysulfides and polyselenides appears to be a possibility under such circumstances (18, 34). At moderate pH values and under reducing conditions, both elements are well within their stability fields and a mixture of the two is Cited by: Selenite broth is used as an enrichment medium for the isolation of Salmonella and Shigella from stool, urine, water and food products. It is the most widely used enrichment medium to isolate Salmonella Typhi from fecal specimen of suspected patients and/or from carriers during Salmonella outbreaks.

  Finally, Selenite’s brilliant white radiance symbolizes the angelic realms and allows us to communicate with these spiritual beings. By placing a Selenite crystal upon your forehead, you can feel the energy of your guardian angels coming down upon you. Here we report that the biosynthesis of organic selenium was accomplished using the whole cell bioconversion of sodium selenite under controlled Bifidobacterium bifidum BGN4 culture conditions. The total amount of organic and inorganic selenium was quantified using an inductively coupled plasma-atomic emission spectrometer (ICP-AES).Cited by: 2.


Share this book
You might also like
Paris lectures.

Paris lectures.

Passion, prejudice and privilege

Passion, prejudice and privilege

Water supply of the South Andaman Island with references to neighbouring islands

Water supply of the South Andaman Island with references to neighbouring islands

A field guide to the birds of East and Central Africa

A field guide to the birds of East and Central Africa

List of crude oil producers 1978

List of crude oil producers 1978

Village of stars.

Village of stars.

Regulations of the Legion of Saint Patrick

Regulations of the Legion of Saint Patrick

Will You Be My Valentine (Minnie and Moo)

Will You Be My Valentine (Minnie and Moo)

Direction of the irradiance vector in the sea

Direction of the irradiance vector in the sea

Creating a website

Creating a website

Time and tide

Time and tide

Modern methods of chemical analysis

Modern methods of chemical analysis

Whos who in the Bulgarian corruption

Whos who in the Bulgarian corruption

Works of art and artists in England

Works of art and artists in England

Reduction of selenite under controlled conditions by Yen Thi Hoang Truong Download PDF EPUB FB2

Selenite reductase with a molecular weight of * kD was detected in cell-free extracts and a protein with a molecular weight of * kD was detected that reduced both selenate and nitrate. The bacterial isolate is a strict aerobe, reducing selenite to elemental red selenium under aerobic conditions only.

Pseudomonas sp. strain CA5 might be Cited by: Carbon dosing control required to minimize sulfate reduction Solids separation step is critical for capture of small Se particles On-going testing of MBBR for different operating conditions File Size: 1MB.

In the case of selenite, the reduction by ferrous iron is barely detectable at very low concentrations of oxygen. However, at concentrations of ± 50 ppmv in the controlled Reduction of selenite under controlled conditions book glove box, more iron oxide particles were formed at a higher initial Fe(II) concentration in the system and with time.

Optimal selenium reduction occurred under aerobic conditions between pH and and at temperatures of 25 to 35 °C. The value of mean reduction rates was  ±  μM h −1 at 25 °C for the reduction of  mM by: This test was conduct in a pH drift mode and initial pH was controlled by different initial Fe(II) concentration.

HSeO 3 − and SeO 3 2− are the predominant species of selenite at pH below and aboverespectively (Kang et al., ; Kang et al., ).No Se(IV) was removed in the control test without Fe(II) (Fig. 1a), probably because the electrostatic repulsion between SeO 3 2− ions Cited by: 2. To explore the possible effect of extracellular flavins on selenite reduction, 1 μM FMN, a concentration close to the level naturally secreted by cells under anaerobic conditi was dosed to Cited by: Selenite reduction, which occurs under aerobic, anoxic and anaerobic conditions, [35][36][37] can be simplified to a twostep process: (1) selenate (SeO 22 4) to selenite (SeO 22 3) conversion.

The photocatalytic reduction of selenite and selenate, with a greater emphasis on selenate, has been extensively studied using TiO 2 semiconductor as catalyst. From such studies it has been found that in the presence of formic acid as a hole scavenger, Cited by: Wangbing Zhang, Wuer Gan, Lijun Shao, Xiangqin Lin.

Flow‐Injection Online Reduction Atomic Fluorescence Spectrometry Determination of Se(IV) and Se(VI) with Electrochemical Hydride Generation. Spectroscopy Letters39 (6), DOI: /Cited by: Removal of selenite ions from aqueous solutions under anoxic condition at pH 6– by zero valent iron steel wool (ZVI-SW) was investigated in bench-scale kinetic experiments using wet chemical, microscopic and spectroscopic techniques (X-ray photoelectron spectroscopy).Cited by: 3.

Palladium(II) reduction to Pd(0) nanoparticles by Geobacter sulfurreducens was explored under conditions of neutral pH, 30 °C and concentrations of 25, 50 and mg Pd(II)/L aiming to. Se(VI) reduction was catalyzed by enzymes of the sulfate reducing pathway. Enzyme SerT is a novel selenite reductase in the periplasm.

Se(IV) reduction can be generated through at least two pathways in strain S The aerobic bacteria and enzymes have a potential for bioremediation of Se by: 7. Introduction. Selenium is an essential element for humans, but it is associated with acute toxicity above mg l −1 and with mutagenicity above 12 mM [1,2].It commonly exists under four oxidation states, among which Se(IV) as selenite (SeO 3 2−) and Se(VI) as selenate (SeO 4 2−) are the most stable species in s, Se(IV) is more toxic than Se(VI) [].Cited by: 1.

The value of k 1 in this sample was the same as that in natural seawater under the same pH, temperature and ionic strength conditions suggesting that possible interactions of major cations with sulfide and selenite may have a minor but significant effect on the by:   This mechanism could result in an incomplete selenite reduction under oxic growth conditions during a limited time frame (Fig.

4), which is consistent with a previous study in C. testosteroni. Moreover, the large Se(0) particle chains could be extremely unmatched for hyphae, and thus the particle chains should be released only upon hyphal lysis or fragmentation (Fig.

2 d, f).Cited by: The environmental conditions for the planned geological disposal of radioactive waste —including hyper-alkaline pH, radiation or anoxia—are expected to be extremely harsh for microbial activity.

However, it is thought that microbial communities will develop in these repositories, and this would have implications for geodisposal integrity and the control of radionuclide migration through Author: Miguel Angel Ruiz-Fresneda, Jaime Gomez-Bolivar, Josemaria Delgado-Martin, Maria del Mar Abad-Ortega.

The reduction–oxidation reaction between aqueous selenite (SeO 3 2-) and siderite (FeCO 3(s)) was monitored by in situ, time-resolved X-ray absorption near-edge structure (XANES) spectroscopy at the selenium K edge in a controlled electrochemical environment.

Spectral evolutions showed that more than 60% of selenite was reduced at the siderite surface after 20 h of experiment, at which time. Optimal selenium reduction occurred under aerobic conditions between pH and and at temperatures of 25 to 35°C.

Reduction of both selenite and selenate was unaffected by a number of anions except for sulfite, chromate, and tungstate ions, which inhibited both growth and by: @article{osti_, title = {Reduction of selenite to elemental selenium by Enterobacter cloacae SLD1a-1}, author = {Dungan, R S and Frankenberger, Jr, W T}, abstractNote = {The facultative anaerobic bacterium Enterobacter cloacae strain SLD1a-1 was studied in washed cell suspensions to assess optimal conditions required for the reduction of selenite (SeO{sub 3}{sup 2{minus}}) to elemental.

Automation and Control - The reduction of selenite by enterococci. Author(s): Tilton, R. see more details faecalis N83 actively reduced selenite to Se; the conditions of the reaction are described. Record Number: Author: R. Tilton. precipitate indicates the formation of Se0 via the reduction of selenite.

Under aerobic conditions the strain removed about mM of selenite from the media during a 7-day incubation (data not shown). Effect of Selenite and Selenate on Growth Neither selenite nor selenate at 64 mM concentrations completely blocked the growth of T.

kashmirensis.These results indicate that dissimilatory selenate reduction to elemental selenium is the major sink for selenium oxyanions in anoxic sediments. In addition, they suggest application as a treatment process for removing selenium oxyanions from wastewaters and also offer an explanation for the presence of selenite in oxic by: New selenium solution speciation method by ion chromatography + gamma counting and its application to FeS2-controlled reducing conditions.

Radiochimica Acta90 () DOI: /ract_ David Amouroux, Christophe P cheyran, Olivier F. X. by: