Browse
Submit Data
Databases
API
Help

Dataset Information

25 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Using real-time UV-visible spectrophotometer to assess an Al-Zn-Mg-Cu alloy's dissolution in acidic solution.

ABSTRACT: Applicability and limitations of using online non-destructive ultraviolet-visible (UV-vis) spectrophotometer to monitor the dissolution of an Al-Zn-Mg-Cu alloy in HCl-containing solution were studied. Inductively coupled plasma atomic emission spectrometry results indicate that the spectrum absorbance at 252 nm is mainly attributed to Cu-containing complexes. Surprisingly, an hours-long 'induction' period was observed from UV-vis results. This is not a real indicator of induction for Al dissolution as revealed by electrochemical impedance spectrum, actually it reflects the alloy's galvanic corrosion nature that Cu species are released after Al, Zn and Mg species.

SUBMITTER: Sun Q

PROVIDER: S-EPMC7735366 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Using real-time UV-visible spectrophotometer to assess an Al-Zn-Mg-Cu alloy's dissolution in acidic solution.

Sun Qingqing Q Yang Yang Y Wang Shuai S Liang Panyi P Lin Bin B Li Huabing H

Royal Society open science 20201104 11

Applicability and limitations of using online non-destructive ultraviolet-visible (UV-vis) spectrophotometer to monitor the dissolution of an Al-Zn-Mg-Cu alloy in HCl-containing solution were studied. Inductively coupled plasma atomic emission spectrometry results indicate that the spectrum absorbance at 252 nm is mainly attributed to Cu-containing complexes. Surprisingly, an hours-long 'induction' period was observed from UV-vis results. This is not a real indicator of induction for Al dissolut ...[more]

PMID: 33391779

Similar Datasets

Direct observation of atomic-scale origins of local dissolution in Al-Cu-Mg alloys.

Project description:Atomistic chemical inhomogeneities are anticipated to induce dissimilarities in surface potentials, which control corrosion initiation of alloys at the atomic scale. Precise understanding of corrosion is therefore hampered by lack of definite information describing how atomistic heterogeneities regulate the process. Here, using high-angle annular dark-field (HAADF) scanning transmission electron microscope (STEM) and electron energy loss spectroscopy (EELS) techniques, we systematically analyzed the Al20Cu2Mn3 second phase of 2024Al and successfully observed that atomic-scale segregation of Cu at defect sites induced preferential dissolution of the adjacent zones. We define an "atomic-scale galvanic cell", composed of zones rich in Cu and its surrounding matrix. Our findings provide vital information linking atomic-scale microstructure and pitting mechanism, particularly for Al-Cu-Mg alloys. The resolution achieved also enables understanding of dealloying mechanisms and further streamlines our comprehension of the concept of general corrosion.

| S-EPMC5175146 | biostudies-literature

Characterization of Zr-Containing Dispersoids in Al-Zn-Mg-Cu Alloys by Small-Angle Scattering.

Project description:The characterization of Zr-containing dispersoids in aluminum alloys is challenging due to their broad size distribution, low volume fraction, and heterogeneous distribution within the grains. In this work, small-angle X-ray scattering (SAXS) and small-angle neutron scattering (SANS) were compared to scanning electron microscopy (SEM) and transmission electron microscopy (TEM) regarding their capability to characterize Zr-containing dispersoids in aluminum alloys. It was demonstrated that both scattering techniques are suitable tools to characterize dispersoids in a multi-phase industrial 7xxx series aluminum alloy. While SAXS is more sensitive than SANS due to the high electron density of Zr-containing dispersoids, SANS has the advantage of being able to probe a much larger sample volume. The combination of both scattering techniques allows for the verification that the contribution from dispersoids can be separated from that of other precipitate phases such as the S-phase or GP-zones. The size distributions obtained from SAXS, SANS and TEM showed good agreement. The SEM-derived size distributions were, however, found to significantly deviate from those of the other techniques, which can be explained by considering the resolution-limited restrictions of the different techniques.

| S-EPMC9919802 | biostudies-literature

Characterisation of a High-Performance Al-Zn-Mg-Cu Alloy Designed for Wire Arc Additive Manufacturing.

Project description:Ever-increasing demands of industrial manufacturing regarding mechanical properties require the development of novel alloys designed towards the respective manufacturing process. Here, we consider wire arc additive manufacturing. To this end, Al alloys with additions of Zn, Mg and Cu have been designed considering the requirements of good mechanical properties and limited hot cracking susceptibility. The samples were produced using the cold metal transfer pulse advanced (CMT-PADV) technique, known for its ability to produce lower porosity parts with smaller grain size. After material simulations to determine the optimal heat treatment, the samples were solution heat treated, quenched and aged to enhance their mechanical performance. Chemical analysis, mechanical properties and microstructure evolution were evaluated using optical light microscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray fluorescence analysis and X-ray radiography, as well as tensile, fatigue and hardness tests. The objective of this research was to evaluate in detail the mechanical properties and microstructure of the newly designed high-performance Al-Zn-based alloy before and after ageing heat treatment. The only defects found in the parts built under optimised conditions were small dispersed porosities, without any visible cracks or lack of fusion. Furthermore, the mechanical properties are superior to those of commercial 7xxx alloys and remarkably independent of the testing direction (parallel or perpendicular to the deposit beads). The presented analyses are very promising regarding additive manufacturing of high-strength aluminium alloys.

| S-EPMC7178362 | biostudies-literature

Precipitation of a new platelet phase during the quenching of an Al-Zn-Mg-Cu alloy.

Project description:A previously undescribed high aspect ratio strengthening platelet phase, herein named the Y-phase, has been identified in a commercial Al-Zn-Mg-Cu alloy. Differential scanning calorimetry indicates that this phase only precipitates at temperature and cooling rate of about 150-250 °C and 0.05-300 K/s, respectively. This precipitate is shown to be responsible for a noticeable improvement in mechanical properties. Aberration corrected scanning transmission electron microscopy demonstrates the minimal thickness (~1.4 nm) precipitate plates are isostructural to those of the T1 (Al2CuLi) phase observed in Al-Cu-Li alloys. Low voltage chemical analysis by energy dispersive X-ray spectroscopy and electron energy loss spectroscopy gives evidence of the spatial partitioning of the Al, Cu and Zn within the Y-phase, as well as demonstrating the incorporation of a small amount of Mg.

| S-EPMC4793252 | biostudies-literature

A combined experimental and computational study on the reaction of fluoroarenes with Mg-Mg, Mg-Zn, Mg-Al and Al-Zn bonds.

Project description:Through a combined experimental and computational (DFT) approach, the reaction mechanism of the addition of fluoroarenes to Mg-Mg bonds has been determined as a concerted SNAr-like pathway in which one Mg centre acts as a nucleophile and the other an electrophile. The experimentally determined Gibbs activation energy for the addition of C6F6 to a Mg-Mg bond of a molecular complex, ΔG‡298 K(experiment) = 21.3 kcal mol-1 is modelled by DFT with the ωB97X functional, ΔG‡298 K(DFT) = 25.7 kcal mol-1. The transition state for C-F activation involves a polarisation of the Mg-Mg bond and significant negative charge localisation on the fluoroarene moiety. This transition state is augmented by stabilising closed-shell Mg···F ortho interactions that, in combination with the known trends in C-F and C-M bond strengths in fluoroarenes, provide an explanation for the experimentally determined preference for C-F bond activation to occur at sites flanked by ortho-fluorine atoms. The effect of modification of both the ligand coordination sphere and the nature and polarity of the M-M bond (M = Mg, Zn, Al) on C-F activation has been investigated. A series of highly novel β-diketiminate stabilised complexes containing Zn-Mg, Zn-Zn-Zn, Zn-Al and Mg-Al bonds has been prepared, including the first crystallographic characterisation of a Mg-Al bond. Reactions of these new M-M containing complexes with perfluoroarenes were conducted and modelled by DFT. C-F bond activation is dictated by the steric accessibility, and not the polarity, of the M-M bond. The more open coordination complexes lead to enhanced Mg···F ortho interactions which in turn lower the energy of the transition states for C-F bond activation.

| S-EPMC5897846 | biostudies-other

A mobile microvolume UV/visible light spectrophotometer for the measurement of levofloxacin in saliva.

Project description:IntroductionTherapeutic drug monitoring (TDM) for personalized dosing of fluoroquinolones has been recommended to optimize efficacy and reduce acquired drug resistance in the treatment of MDR TB. Therefore, the aim of this study was to develop a simple, low-cost, robust assay for TDM using mobile UV/visible light (UV/VIS) spectrophotometry to quantify levofloxacin in human saliva at the point of care for TB endemic settings.MethodsAll experiments were performed on a mobile UV/VIS spectrophotometer. The levofloxacin concentration was quantified by using the amplitude of the second-order spectrum between 300 and 400 nm of seven calibrators. The concentration of spiked samples was calculated from the spectrum amplitude using linear regression. The method was validated for selectivity, specificity, linearity, accuracy and precision. Drugs frequently co-administered were tested for interference.ResultsThe calibration curve was linear over a range of 2.5-50.0 mg/L for levofloxacin, with a correlation coefficient of 0.997. Calculated accuracy ranged from -5.2% to 2.4%. Overall precision ranged from 2.1% to 16.1%. Application of the Savitsky-Golay method reduced the effect of interferents on the quantitation of levofloxacin. Although rifampicin and pyrazinamide showed analytical interference at the lower limit of quantitation of levofloxacin concentrations, this interference had no implication on decisions regarding the levofloxacin dose.ConclusionsA simple UV/VIS spectrophotometric method to quantify levofloxacin in saliva using a mobile nanophotometer has been validated. This method can be evaluated in programmatic settings to identify patients with low levofloxacin drug exposure to trigger personalized dose adjustment.

| S-EPMC7816168 | biostudies-literature

Atomic Structure of Hardening Precipitates in Al-Mg-Si Alloys: Influence of Minor Additions of Cu and Zn.

Project description:Shifting toward sustainability and low carbon emission necessitates recycling. Aluminum alloys can be recycled from postconsumer scrap with approximately 5% of the energy needed to produce the same amount of primary alloys. However, the presence of certain alloying elements, such as copper and zinc, as impurities in recycled Al-Mg-Si alloys is difficult to avoid. This work has investigated the influence of tiny concentrations of Cu (0.05 wt %) and Zn (0.06 wt %), individually and in combination, on the precipitate crystal structures in Al-Mg-Si alloys in peak aged and overaged conditions. To assess whether such concentrations can affect the hardening precipitate structures, atomic resolution high-angle annular dark-field scanning transmission electron microscopy and atom probe tomography were adopted. The results indicate that low levels of Cu or Zn have a significant influence. Both elements showed a relatively high tendency to incorporate into precipitate structures, where Cu occupies specific atomic sites, creating its own local atomic configurations. However, Zn exhibited distinct behavior through the formation of extended local areas with 2-fold symmetry and mirror planes, not previously observed in precipitates in Al-Mg-Si alloys. Incorporation of Cu and/or Zn will influence the precipitates' electrochemical potential relative to matrix- and precipitate-free zones and thus the corrosion resistance. Furthermore, the presence of Cu/Zn structures (e.g., β'Cu, Q'/C) enhances the thermal stability of these precipitates and, accordingly, the mechanical properties of the material. The results obtained from this work are highly relevant to the topic of recycling of aluminum alloys, where accumulation of certain alloying elements is almost unavoidable; thus, tight compositional control might be critical to avoid quality degradation.

| S-EPMC10722592 | biostudies-literature

Study on Mg/Al Weld Seam Based on Zn-Mg-Al Ternary Alloy.

Project description:Based on the idea of alloying welding seams, a series of Zn-xAl filler metals was calculated and designed for joining Mg/Al dissimilar metals by gas tungsten arc (GTA) welding. An infrared thermography system was used to measure the temperature of the welding pool during the welding process to investigate the solidification process. It was found that the mechanical properties of the welded joints were improved with the increasing of the Al content in the Zn-xAl filler metals, and when Zn-30Al was used as the filler metal, the ultimate tensile strength could reach a maximum of 120 MPa. The reason for the average tensile strength of the joint increasing was that the weak zone of the joint using Zn-30Al filler metal was generated primarily by α-Al instead of MgZn2. When Zn-40Al was used as the filler metal, a new transition zone, about 20 μm-wide, appeared in the edge of the fusion zone near the Mg base metal. Due to the transition zones consisting of MgZn₂- and Al-based solid solution, the mechanical property of the joints was deteriorated.

| S-EPMC5453102 | biostudies-other

Microstructural Evolution and Dynamic Softening Mechanisms of Al-Zn-Mg-Cu Alloy during Hot Compressive Deformation.

Project description:The hot deformation behavior and microstructural evolution of an Al-Zn-Mg-Cu (7150) alloy was studied during hot compression at various temperatures (300 to 450 °C) and strain rates (0.001 to 10 s-1). A decline ratio map of flow stresses was proposed and divided into five deformation domains, in which the flow stress behavior was correlated with different microstructures and dynamic softening mechanisms. The results reveal that the dynamic recovery is the sole softening mechanism at temperatures of 300 to 400 °C with various strain rates and at temperatures of 400 to 450 °C with strain rates between 1 and 10 s-1. The level of dynamic recovery increases with increasing temperature and with decreasing strain rate. At the high deformation temperature of 450 °C with strain rates of 0.001 to 0.1 s-1, a partially recrystallized microstructure was observed, and the dynamic recrystallization (DRX) provided an alternative softening mechanism. Two kinds of DRX might operate at the high temperature, in which discontinuous dynamic recrystallization was involved at higher strain rates and continuous dynamic recrystallization was implied at lower strain rates.

| S-EPMC5453149 | biostudies-other

Microstructure Evolution and Localized Corrosion Susceptibility of an Al-Zn-Mg-Cu-Zr 7xxx Alloy with Minor Cr Addition.

Project description:Microstructure optimization of Al-Zn-Mg-Cu-Zr aluminum alloys, particularly through recrystallization inhibition, for improved strength and corrosion resistance properties has been an important consideration in alloy development for aerospace applications. Addition of rare earth elements, sometimes combined with Cr, has been found to be beneficial in this regard. In this study, the role of a single addition of 0.1 wt.% Cr on microstructure evolution of an Al-Zn-Mg-Cu-Zr (7449) alloy during processing was systematically investigated by optical light microscopy, scanning electron microscopy, electron backscatter diffraction and scanning transmission electron microscopy. Susceptibility to localized corrosion after aging to T4, T6 and T76 conditions was evaluated by potentiodynamic polarization (PDP) measurements and an intergranular corrosion (IGC) test. A decrease in recrystallized fraction with 0.1 wt.% Cr addition was observed, which is attributed to the formation of Cu- and Zn-containing E (Al18Mg3Cr2) dispersoids and the larger as-cast grain size. Moreover, the depletion of alloying elements from solid solution due to the formation of the Cu- and Zn-containing E (Al18Mg3Cr2) dispersoids and η Mg(Zn,Cu,Al)2 phase at its interface affects grain-boundary precipitation. The observed decrease in localized corrosion susceptibility with minor Cr addition is correlated with the microstructure and equally discussed.

| S-EPMC9918105 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data