scholarly journals Biogenic Formation of As-S Nanotubes by Diverse Shewanella Strains

2009 ◽  
Vol 75 (21) ◽  
pp. 6896-6899 ◽  
Author(s):  
Shenghua Jiang ◽  
Ji-Hoon Lee ◽  
Min-Gyu Kim ◽  
Nosang V. Myung ◽  
James K. Fredrickson ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Fine Structure ◽  
Reduction Rate ◽  
Shewanella Oneidensis ◽  
Chemical Properties ◽  
Anaerobic Conditions ◽  
X Ray ◽  
Shewanella Alga ◽  
X Ray Absorption ◽  
And Chemical Properties

ABSTRACT Shewanella sp. strain HN-41 was previously shown to produce novel, photoactive, As-S nanotubes via the reduction of As(V) and S2O3 2− under anaerobic conditions. To determine if this ability was unique to this bacterium, 10 different Shewanella strains, including Shewanella sp. strain HN-41, Shewanella sp. strain PV-4, Shewanella alga BrY, Shewanella amazonensis SB2B, Shewanella denitrificans OS217, Shewanella oneidensis MR-1, Shewanella putrefaciens CN-32, S. putrefaciens IR-1, S. putrefaciens SP200, and S. putrefaciens W3-6-1, were examined for production of As-S nanotubes under standardized conditions. Of the 10 strains examined, three formed As-S nanotubes like those of strain HN-41. While Shewanella sp. strain HN-41 and S. putrefaciens CN-32 rapidly formed As-S precipitates in 7 days, strains S. alga BrY and S. oneidensis MR-1 reduced As(V) at a much lower rate and formed yellow As-S after 30 days. Electron microscopy, energy-dispersive X-ray spectroscopy, and extended X-ray absorption fine-structure spectroscopy analyses showed that the morphological and chemical properties of As-S formed by strains S. putrefaciens CN-32, S. alga BrY, and S. oneidensis MR-1 were similar to those previously determined for Shewanella sp. strain HN-41 As-S nanotubes. These studies indicated that the formation of As-S nanotubes is widespread among Shewanella strains and is closely related to bacterial growth and the reduction rate of As(V) and thiosulfate.

scholarly journals PHYSICAL AND CHEMICAL STUDIES OF OVERROOF ROCKS OF CLAY SHALES OF THE DZHERDANAK DEPOSIT

2021 ◽  
pp. 16-21
Keyword(s):  
Electron Microscopy ◽  
Fine Structure ◽  
Chemical Properties ◽  
Mineralogical Composition ◽  
Physical And Chemical Properties ◽  
X Ray ◽  
Clay Shales ◽  
Chemical Studies ◽  
Physical And Chemical ◽  
And Chemical Properties

The purpose of this study is study of the physical and chemical properties of the overburden of the Dzherdanak deposit. The chemical and mineralogical composition of the overburden of the Djerdanak deposit has been studied by the methods of X-ray and thermography, electron microscopy and infrared spectroscopy. The main phases are quartz, kaolinite and muscovite. The study of the fine structure of the rock under an electron microscope showed the homogeneity of the rock with pronounced uniform inclusions, which is preserved even after firing. Changes in the rock after firing at 1050 °C have been determined. The formation of mullite at this temperature has been established.

scholarly journals A Review of Morphological and Chemical Properties of Porous Asphalt

CONSTRUCTION ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 45-49
Author(s):  
N.E. Jasni ◽  
Khairil Azman Masri ◽  
R.P. Jaya
Keyword(s):  
Electron Microscopy ◽  
Chemical Composition ◽  
Asphalt Mixture ◽  
Chemical Properties ◽  
Fine Aggregate ◽  
Air Voids ◽  
Porous Asphalt ◽  
X Ray ◽  
Scanning Electron ◽  
And Chemical Properties

Porous asphalt mixture is also known as gap graded mixture with less amount of fine aggregate has led the mixture contains high air voids, tends to make the mixture less durable and high porousity. Hence, past researchers has investigate on how to increase the strength of porous asphalt mixture by the addition of additive such as fiber and  nanomaterials. The chemical and physical properties of porous asphalt mixture was highlighted in this paper to compare its structure, the bonding between the materials and its chemical composition that exist. This paper reviews on how additive affect the asphalt mixture in terms of Scanning Electron Microscopy (SEM), X-Ray Diffractions (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). These tests are selected to improve the asphalt mixture according to the morphological and chemical properties of porous asphalt. This study is expected to identify the morphological and chemical composition of the materials in asphalt mixture.

Characterization of U(VI)-Acidithiobacillus ferrooxidans complexes using EXAFS, transmission electron microscopy, and energy-dispersive X-ray analysis

2003 ◽  
Vol 91 (10) ◽  
Author(s):  
Mohamed Merroun ◽  
C. Hennig ◽  
A. Rossberg ◽  
T. Reich ◽  
S. Selenska-Pobell
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Fine Structure ◽  
Acidithiobacillus Ferrooxidans ◽  
Energy Dispersive ◽  
X Ray ◽  
Transmission Electron ◽  
Molecular Scale ◽  
X Ray Absorption

SummaryWe used a combination of Extended X-ray Absorption Fine Structure (EXAFS) spectroscopy, Transmission Electron Microscopy (TEM) and Energy-Dispersive X-ray (EDX) analysis to conduct molecular scale studies on U(VI) interaction with three recently described eco-types of

scholarly journals Temperature reversible synergistic formation of cerium oxyhydride and Au hydride: a combined XAS and XPDF study

2020 ◽  
Vol 22 (34) ◽  
pp. 18882-18890
Author(s):  
Adam H. Clark ◽  
Nadia Acerbi ◽  
Philip A. Chater ◽  
Shusaku Hayama ◽  
Paul Collier ◽  
...  
Keyword(s):  
Fluorescence Detection ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Au Catalyst ◽  
Total Scattering ◽  
X Ray ◽  
Physical And Chemical ◽  
X Ray Absorption ◽  
And Chemical Properties

In situ studies on the physical and chemical properties of the interaction with hydrogen with a ceria coated alumina supported Au catalyst using fluorescence detection X-ray absorption near edge spectroscopy and X-ray total scattering.

scholarly journals Synchrotron X-Ray Absorption Spectroscopy Study of Self-Assembled Nanoparticles Synthesized from Fe(acac)3and Pt(acac)2

2012 ◽  
Vol 2012 ◽  
pp. 1-4 ◽  
Author(s):  
K. Chokprasombat ◽  
C. Sirisathitkul ◽  
P. Harding ◽  
S. Chandarak ◽  
R. Yimnirun
Keyword(s):  
Electron Microscopy ◽  
Fine Structure ◽  
Exafs Spectrum ◽  
Fept Nanoparticles ◽  
Spectroscopy Study ◽  
Edge Structure ◽  
X Ray ◽  
Monodisperse Nanoparticles ◽  
X Ray Absorption ◽  
Absorption Technique

The synchrotron X-ray absorption technique was used to complement electron microscopy in the investigation of nanoparticles synthesized from the coreduction of iron acetylacetonate, Fe(acac)3and platinum acetylacetonate, Pt(acac)2. A much higher Pt composition than Fe leads to an extended X-ray absorption fine structure (EXAFS) spectrum for the sample that differs from that of fcc FePt nanoparticles. Most importantly, X-ray absorption near-edge structure (XANES) spectra clearly indicate the existence ofα-Fe2O3and Pt metal. Since these monodisperse nanoparticles have a diameter of around 4 nm and tend to self-assemble into hexagonal arrangements, they can be modeled as Pt-rich cores with anα-Fe2O3shell stabilized by organic surfactants.

Characterization of Y/TiO2 Nanoparticles and their Reactivity for CO2 Photoreduction

2011 ◽  
Vol 55-57 ◽  
pp. 1506-1510 ◽  
Author(s):  
Jing Wei ◽  
Xin Tan ◽  
Tao Yu ◽  
Lin Zhao
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Sol Gel ◽  
Chemical Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Uv Illumination ◽  
Transmission Electron ◽  
And Chemical Properties

A series of Y/TiO2nanoparticles (NPs) were synthesized via sol-gel method. The crystal structures, morphologies and chemical properties were characterized using X-ray diffraction (XRD), high resolution transmission electron microscopy (HR-TEM) and X-ray photoelectron spectroscopy (XPS). We investigated the effects of different doping amounts of Y on the reaction of CO2photoreduction. The results shown that 0.1 wt.%Y/TiO2(0.1YT) performed the highest photocatalytic activity, which yielded 384.62 µmol/g∙cat. formaldehyde after 6 h of UV illumination.

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