scholarly journals Investigation of sodium borohydride and hydrazine oxidation on gold nanoparticles modified zinc–cobalt coating

Chemija ◽  
2019 ◽  
Vol 30 (3) ◽  
Author(s):  
Aušrinė Zabielaitė ◽  
Aldona Balčiūnaitė ◽  
Dijana Šimkūnaitė ◽  
Jūratė Vaičiūnienė ◽  
Algirdas Selskis ◽  
...  
Keyword(s):  
Electrochemical Oxidation ◽  
Sodium Borohydride ◽  
Inductively Coupled Plasma ◽  
Low Cost ◽  
Titanium Substrate ◽  
Optical Emission ◽  
Alkaline Solutions ◽  
Inductively Coupled ◽  
Cobalt Coating

This work presents the investigation of the electrochemical oxidation of hydrazine and sodium borohydride ions in alkaline solutions on the Au nanoparticles modified ZnCo coating surface, which was deposited on the titanium substrate (termed as AuZnCo/Ti). The AuZnCo/Ti catalysts were prepared via a facile electrochemical deposition technique followed by a simple and low-cost galvanic displacement. Scanning electron microscopy, energy dispersive X-ray analysis and inductively coupled plasma optical emission spectroscopy were used for characterization of the prepared catalysts surface morphology, structure and composition, whereas their electrocatalytic behaviour was investigated for the electrochemical oxidation of hydrazine and sodium borohydride in an alkaline medium using cyclic voltammetry. It has been determined that the AuZnCo/Ti catalysts with Au loadings of 31, 63 and 306 µg cm–2 show enhanced catalytic activity towards the electrochemical oxidation of both hydrazine and sodium borohydride as compared to that of the ZnCo/Ti catalyst.

scholarly journals Hydrothermal Synthesis of Co-Ru Alloy Particle Catalysts for Hydrogen Generation from Sodium Borohydride

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Marija Kurtinaitienė ◽  
Albina Žielienė ◽  
Loreta Tamašauskaitė-Tamašiūnaitė ◽  
Algis Selskis ◽  
Arūnas Jagminas
Keyword(s):  
Sodium Borohydride ◽  
Inductively Coupled Plasma ◽  
Hydrogen Generation ◽  
Catalytic Properties ◽  
Optical Emission ◽  
Emission Spectrometry ◽  
Alkaline Solutions ◽  
Inductively Coupled ◽  
Cost Efficient ◽  
Hydrothermal Approach

We report the synthesis ofμm and sub-μm-sized Co, Ru, and Co-Ru alloy species by hydrothermal approach in the aqueous alkaline solutions (pH ≥ 13) containing CoCl2and/or RuCl3, sodium citrate, and hydrazine hydrate and a study of their catalytic properties for hydrogen generation by hydrolysis of sodium borohydride solution. This way provides a simple platform for fabrication of the ball-shaped Co-Ru alloy catalysts containing up to 12 wt% Ru. Note that bimetallic Co-Ru alloy bowls containing even 7 at.% Ru have demonstrated catalytic properties that are comparable with the ones of pure Ru particles fabricated by the same method. This result is of great importance in view of the preparation of cost-efficient catalysts for hydrogen generation from borohydrides. The morphology and composition of fabricated catalyst particles have been characterized using scanning electron microscopy, energy dispersive X-ray diffraction, and inductively coupled plasma optical emission spectrometry.

Effect of Annealing Conditions on the Dissolution Process of Complex Carbonitrides in a V-Nb-Ti Microalloyed Steel

2018 ◽  
Vol 941 ◽  
pp. 21-26
Author(s):  
Gloria Basanta ◽  
Ana L. Rivas ◽  
Ervis Díaz ◽  
Carlos Parra
Keyword(s):  
Inductively Coupled Plasma ◽  
Microalloyed Steel ◽  
Optical Emission ◽  
Dissolution Process ◽  
Emission Spectrometry ◽  
Inductively Coupled ◽  
Annealing Conditions ◽  
Plasma Optical Emission Spectrometry

The present work has been undertaken to assess the evolution of dissolution process of large dendritic precipitates in a V-Nb-Ti microalloyed steel. The study was performed by reheating the samples at 1250°C, simulating the industrial reheating practices at laboratory scale and in situ, following industrial profile; afterwards the samples were quenched in 10%NaCl aqueous solution. The characterization of the material was carried out by scanning electron microscopy accompanied with dispersive energy spectrometry, and chemical analysis by inductively coupled plasma optical emission spectrometry. The results showed a partial dissolution of dendritic precipitates. This process ocurred by a progressive dissolving the Nb-rich shells formed over cuboidal particles and primary arm of well-faceted dendritic precipitates, and by fragmentation and spheroidization of secondary branches. These processes gave rise to spherical Nb rich precipitates and cuboidal particles at the reheating conditions used in this study. Both type of particles contain vanadium.

GROWTH AND SPECTROSCOPIC CHARACTERIZATION OF Mg:Ce:Cu:LiNbO3 CRYSTALS

2008 ◽  
Vol 22 (15) ◽  
pp. 1487-1495 ◽  
Author(s):  
YEXIA FAN ◽  
HONGTAO LI ◽  
LIANCHENG ZHAO
Keyword(s):  
Mass Spectrometry ◽  
Defect Structure ◽  
Inductively Coupled Plasma ◽  
Optical Emission ◽  
Spectroscopic Characterization ◽  
Threshold Concentration ◽  
Ir Absorption ◽  
X Ray ◽  
Inductively Coupled

Congruent Ce (0.1 wt %): Cu (0.05 wt %): LiNbO 3 single crystals doped with 0, 1, 3, 4, 5, 6 mol% MgO respectively were grown by the Czochrolski method in air along the C direction. The inductively coupled plasma optical emission/mass spectrometry (ICP-OE/MS), the X-ray powder diffraction (XRD), the differential thermal analysis (DTA), the ultraviolet-visible (UV-Vis) absorption spectra and the infrared (IR) absorption spectrum were measured and discussed in terms of the spectroscopic characterization and the defect structure of the Mg:Ce:Cu:LiNbO 3 crystals. The results indicated that the Mg:Ce:Cu:LiNbO 3 crystal grown from the congruent composition melt showed large [ Li ]/[ Nb ] ratios, which was closer to stoichiometry, an increase in the Curie temperature and a non-linear shift in the absorption edge with MgO concentration increasing. The threshold concentration of MgO in Mg:Ce:Cu:LiNbO 3 of nearly 5.52 mol% was estimated.

scholarly journals Characterization of Morus species in respect to micro, macro, and toxic elements

2014 ◽  
pp. 229-237 ◽  
Author(s):  
Marija Radojkovic ◽  
Zoran Zekovic ◽  
Biljana Dojcinovic ◽  
Zorica Stojanovic ◽  
Aleksandra Cvetanovic ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Optical Emission ◽  
Emission Spectrometry ◽  
Dry Extract ◽  
Mulberry Leaves ◽  
Inductively Coupled ◽  
Morus Nigra ◽  
Plasma Optical Emission Spectrometry ◽  
White Mulberry

This study examines the mineral composition of the extracts of the fruits, leaves and roots of white mulberry (Morus alba L.) and black mulberry (Morus nigra L.) grown in Serbia. All extract samples of white and black mulberry were analyzed for the content of micro (B, Co, Cr, Cu, Fe, Li, Mn, Ni, Se, Sr, Zn), macro (Ca, Mg, Na), and toxic metals (Al, As, Cd, Hg, Pb) by inductively coupled plasma optical emission spectrometry (ICP-OES). The study revealed that parts of the plant had statistically significant impact on the levels of the examined elements among the two Morus species. All extracts contained high amounts of Ca, Mg, Na, B, Cu, Fe, Mn and Zn. The studies showed that in the most of extracts dominant macro element was Mg (591- 1942 ?g/g of dry extract), while dominant microelements were Zn, B, Cu in all extracts, except for the black mulberry leaves, whose extract was most abundant in Fe (143 ?g/g of dry extract). The highest content of micro and macro elements was detected in the extract of black mulberry leaves. This work contributes to the knowledge of the nutritional properties of Morus species. The obtained results may be useful in the evaluation of new dietary and food products.

A new closed-vessel conductively heated digestion system: fostering plant analysis by inductively coupled plasma optical emission spectroscopy

2014 ◽  
Vol 29 (5) ◽  
pp. 825-831 ◽  
Author(s):  
Kelber Miranda ◽  
Edenir Rodrigues Pereira-Filho ◽  
José Anchieta Gomes Neto
Keyword(s):  
High Throughput ◽  
Inductively Coupled Plasma ◽  
Emission Spectroscopy ◽  
Optical Emission Spectroscopy ◽  
Low Cost ◽  
Optical Emission ◽  
Plant Analysis ◽  
Closed Vessel ◽  
Inductively Coupled ◽  
Plasma Optical Emission Spectroscopy

A high-throughput, low cost and efficient device based on conductive heating and closed-vessels was developed and applied to plant digestion.

scholarly journals Reactivity of Metakaolin in Alkaline Environment: Correlation of Results from Dissolution Experiments with XRD Quantifications

Materials ◽  
2020 ◽  
Vol 13 (10) ◽  
pp. 2214
Author(s):  
Sebastian Scherb ◽  
Mathias Köberl ◽  
Nancy Beuntner ◽  
Karl-Christian Thienel ◽  
Jürgen Neubauer
Keyword(s):  
Inductively Coupled Plasma ◽  
Optical Emission ◽  
Systematic Investigation ◽  
Attenuated Total Reflection ◽  
Emission Spectrometry ◽  
Alkaline Solutions ◽  
X Ray ◽  
Inductively Coupled ◽  
Before And After ◽  
Congruent Dissolution

Systematic investigation of filtrates and filter residues resulting from a 24 h treatment of metakaolin in different alkaline solutions were performed. On filtered metakaolin particles, inductively coupled plasma-optical emission spectrometry (ICP-OES) measurements reveal an enrichment of iron and titanium, which suggests an inhomogeneous distribution of these cations. Since the SiO2/Al2O3 ratio remains constant in all filter residues examined, the dissolution of the Si and Al monomers is congruent. Structural differences, identified by attenuated total reflection–Fourier transform infrared spectroscopy (ATR-FTIR) as a consequence of alkali uptake, influence the X-ray scattering contribution of metakaolin, and thus quantifications with the partial or no known crystal structure (PONKCS) method. This leads to deviations between the degree of reaction calculated from Si and Al solubility from filtrate and that quantified by quantitative powder X-ray diffraction (QPXRD) using the filter residue. Nevertheless, the described changes do not cause a shift in the X-ray amorphous hump in case of congruent dissolution, and thus allow the quantification of the metakaolin before and after dissolution with the same hkl-phase model.

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