Element Solution Research Articles

Study on enhancing the quantitative performance of LIBS for Cu element in liquids based on the chitosan-parafilm enrichment method

Abstract To enhance the accuracy of laser-induced breakdown spectroscopy (LIBS) in detecting heavy metal elements in solutions, a chitosan (CS)-Parafilm (PM) enrichment method is proposed. This method involves drying chitosan-heavy metal complexes on a Parafilm substrate. During the drying of droplets, electrostatic attraction and chelation by CS effectively concentrate analytes. Additionally, the hydrophobic effect of the PM substrate induces Marangoni flow, which drags analytes from the bottom edge to the central top of the droplet surface, effectively suppressing the coffee ring effect (CRE). Using LIBS technology, spectra were uniformly collected in an array on the surface of sediments. Through the analysis of cumulative excitation spectra and measurement repeatability, the results showed that the RSD of the emission lines Cu I 324.754 nm and Cu I 327.396 nm was reduced to 3.85% and 3.78%, respectively. This indicates that the CS-PM enrichment method allows for uniform deposition of analytes within the samples, effectively suppressing the CRE. Quantitative analysis of Cu elements using the CS-PM enrichment method was conducted using PSO-SVM, PSO-BPNN, and random forest (RF) algorithms. The RF algorithm demonstrated the best predictive performance with Rp 2 of 0.977, root mean square error of prediction of 3.86 mg l−1, mean absolute error of 3.0 mg l−1, and RPD of 5.52. Thus, it can be seen that CS-PM effectively improves the repeatability of spectral measurements and the accuracy of quantitative analysis predictions, providing a technical reference for enhancing the stability and quantitative performance of element analysis in liquids using LIBS.

Additive Manufacturing and Precipitation Hardening of Low-Alloyed Copper Alloys Containing Chromium and Hafnium

Copper alloys with chromium and hafnium offer the possibility of precipitation hardening and combine enhanced strength with high electrical and thermal conductivities. The production process, which starts with raw materials, involves powder production by gas atomization and leads to additive manufacturing by laser powder bed fusion with different parameter sets. The aim is to utilize precipitation reactions afterwards in CuHf0.7Cr0.35 during temperature exposure for further property optimization. This research focuses on the low-alloyed copper alloy with hafnium and chromium, compares this with conventionally manufactured specimens, and relates the alloy to additively manufactured specimens of other benchmark alloys such as CuCr1Zr. Measurements of hardness and electrical conductivity are accompanied by metallographic investigations to understand the behavior of CuHf0.7Cr0.35 manufactured by generative methods. In the as-built condition, melting traces remain visible in the microstructure, and hardness values of 101 HV and an electrical conductivity of 17.5 MS/m are reached. Solution annealing completely recrystallizes the microstructure, and the following quenching holds further alloying elements in supersaturated solid solution, resulting in 73 HV and 16.5 MS/m. Subsequent target-oriented precipitation reactions enable peak values of about 190 HV and 42 MS/m. Future research will assess mechanical and physical properties at elevated temperatures and evaluate possible applications.

Tunnel Movement Verification with Parametric Study: Analytical Solution and Finite Element Analysis

Tunnel Movement Verification with Parametric Study: Analytical Solution and Finite Element Analysis

Coupling thermodynamic modelling with experimental study to reveal the evolutionary relationship of pore solutions, products, and compressive strength for lunar regolith simulant geopolymers

Alkali-activation is a highly promising approach for the in situ resource utilisation (ISRU) of lunar regoliths. However, the considerable variation in the composition of lunar regolith simulants can complicate the optimal design of geopolymer mixture ratios, necessitating an in-depth analysis of composition–performance correlations. This study proposes a calculation method that couples thermodynamic modelling with an experimental study to reveal the evolutionary relationship between the pore solution, product formation, and compressive strength. The results indicate that the modulus and dosage of the alkali activator can substantially change the relative content of reactive elements in the pore solution and affect the product type and content. Among these, [Si] and [Al] in the pore solution and gel production are key factors affecting the compressive strength of geopolymers. Understanding these composition–performance relationships is critical for offering essential guidance for performance-based, on-demand material design and optimisation.

A Catalyst Tube-Equipped Dual-Stage Tube Furnace System for Accurate Hg Isotopic Determination of Ore Samples Using Neptune Plus Multicollector Inductively Coupled Plasma Mass Spectrometry.

Mercury (Hg) isotopes, which display mass-dependent fractionation and mass-independent fractionation, provide a multidimensional tracer to decipher the source of metals in mineral deposits. However, mineral ore samples usually contain abundant interfering elements (e.g., Te) that can cause inaccurate Hg isotopic analysis. Available acid digestion and combustion methods failed to remove these interfering elements, hindering the application of Hg isotopes for metallogenetic tracing. Here, we developed a new dual-stage tube furnace system employing a Mn-containing catalyst tube to pretreat mineral ore samples. This method yielded good Hg recoveries (100.5 ± 3.8%, 1SD, n = 15) and low levels of interfering elements in sample solutions, allowing for accurate analysis of a series of ore standard reference materials (GBW-11108v: coal; GSO-3: Cu-Ag sulfide ore; GBW 07859: Au-Te sulfide ore). The new method was also successfully applied to measure the Hg isotopic composition of magmatic and hydrothermal ore deposits, which yielded a large range in Δ199Hg value (-0.19 to 0.22‰) for ore deposits formed in different geological settings, highlighting the future applications of this method for metallogenic tracing, especially tracing the source of metals in mineral ore deposits.

Theoretical investigation on crash performance of bamboo-inspired energy absorption systems based on systematic experimental and numerical analysis

The need for energy-absorbing devices with adaptable crashworthiness is increasingly urgent in various engineering fields with diverse load environments. For this aim, bamboo-inspired modular energy absorption systems have recently been proposed to integrate mechanical efficiency, tunability, and robustness. However, their mechanical responses under varying load velocities have not been systematically studied, which limits the effective prediction and optimization of their crashworthiness. In this study, quasi-static and dynamic experiments were performed on bamboo-inspired systems, discretely assembled using 3D printed steel tube specimens. Matched finite element simulations were conducted using ABAQUS/Explicit. Specific energy absorption and efficiency of these systems respectively exceeded 12.9 J/g and 47 %, surpassing existing discretely assembled systems and rivaling typical cellular materials. Efficient deformation mode with self-locking capability was observed, and sharp impact peak was avoided when the crash velocity was less than 50 m/s. Building upon these findings, a modified spherical shell theory under crashing was developed to predict energy absorption performance of bamboo-inspired system based on the traveling plastic hinge model. The average relative error between the analytical solution and finite element results was found less than 6.5 %. The mean effective stress of the system could exceed 35 MPa under thickness-to-diameter ratio of 5 %. This work presents an efficient and effective approach for optimizing and estimating the crash performance of modular protective devices.

Separation of hafnium from zircon leach solution using anion-exchange resin and production of high-purity zirconia for nuclear applications

The ion exchange process using an anion exchange resin (Bio-Rex 5) was employed with batch and column techniques to isolate nuclear-grade zirconium/hafnium from a leach solution of zircon ore. Batch studies were conducted to optimize the conditions for sorption and desorption of Zr(IV) and Hf(IV). The highest separation factor of 10.3 was achieved under equilibrium conditions of 11.0 mol/L HCl, contact time of 30.0 min, solution volume-to-mass of resin ratio of 0.10, and 15 °C. The sorption process for both metals obeyed a pseudo-second-order model and the experimental sorption data was well-described by both Langmuir and Freundlich models. The maximum sorption capacities were determined to be 46.2 mg/g for Zr(IV) and 37.8 mg/g for Hf(IV). The Zr(IV) and Hf(IV) ions were effectively desorbed by 0.1 mol/L nitric and 2.0 mol/L hydrochloric acid solutions, respectively, with total yields of 89.7 % Zr(IV) and 85.8 % Hf(IV) via multistage desorption processes. In both batch and column techniques, the resin exhibited sorption selectivity for Zr and Hf over interfering elements in the hydrochloric acid leach solution of zircon sand. The loaded resin from real leach solution was subjected to desorption, zirconium sulfate precipitation, and calcination at 650 °C, resulting in a pure zirconia powder suitable for nuclear applications. This technique presents a promising effective method for the selective separation and recovery of high-purity zirconium and hafnium from their natural sources.

Rapid quantitative analysis of three elements (Al, Mg and Fe) in molten zinc based on laser-induced breakdown spectroscopy combined with machine learning algorithm

Hot-dip galvanizing represents one of the most cost-effective methods for the prevention of metal corrosion, and is therefore employed extensively across a range of fields. Carrying out the research and development of technology and devices for quantitative analysis of chemical elements in hot-dip galvanising process can provide theoretical basis and technical support for the efficiency of hot-dip galvanising process and reduction of energy consumption. A machine learning-assisted LIBS combined with a programmable logic controller (PLC) for simultaneous on-line/in-site monitoring of multiple elements in hot-dip galvanising solution (molten zinc) was developed in the current study. The LIBS spectral data of the on-site hot-dip galvanising solution was collected under optimised experimental conditions. In order to further reduce the influence of experimental noise on the analysis performance, the on-site LIBS spectral data were preprocessed and anomalous spectral data were screened based on normalisation and principal component analysis-Mahalanobis distance (PCA-MD). On the basis of the optimised data, component prediction models for three key elements of on-site hot-dip galvanising solution were constructed. The storage and re-call of the model was achieved based on Python combined with LabVIEW, thus real-time prediction of the on-site component content of hot-dip galvanising solution was achieved. The results show that the random forest model presents the best prediction results, in which the R2 is 0.9978 and the RMSE is 0.0013% for Al, the R2 is 0.9984 and the RMSE is 0.0011% for Mg, and the R2 is 0.9932 and the RMSE is 0.0001% for Fe. From the on-site analysis results of the constructed model, its MRE of Al, Mg and Fe is 0.0098, 0.0236, and 0.2102, respectively. In summary, the in-situ/on-line analysis system of hot-dip galvanising solution combined with machine learning constructed in this study shows excellent performance, which can satisfy the needs of hot-dip galvanising solution production site. This study is expected to provide theoretical basis and technical reference for quality control and process optimisation in other production sites in the metallurgical field.

Element release from lead crystal ware and metallic hip flasks

The release of 21 elemental ions from lead crystal ware and metallic hip flasks into different food simulants as well as alcoholic beverages was investigated in this study. For this purpose, an ICP-MS method including a sample pre-treatment based on microwave-assisted digestion was developed and validated. Elemental ion release from lead crystal glasses into artificial tap water, 0.5% citric acid solution and white wine, respectively, was only analysed for Pb. Within 24 h, Pb release from crystal glass was shown to increase with time. To account for repeated use, at least three consecutive release experiments were performed, which showed – with one remarkable exception – constant or decreasing levels of element ion release. However, after four months resting period, Pb release from crystal glass was higher than before. In contrast, all 21 elemental ions were detected to be released from the hip flasks into 0.5% citric acid solution, apple liqueur and herb liqueur, respectively. Release of Cd, Cr, Ni, As, TI, Sn and most prominently Pb from hip flasks was in the range of and above the respective release limit (SRL) as set by the Council of Europe (CoE). When focussing on the third repetition, only one out of six hip flasks met the suggested SRL for all determined elements in all test solutions. This demonstrates both, that the SRLs of the CoE can be met and that producers of hip flasks may have to review their manufacturing processes.

The effect of impurity in vanadium-rich solution on vanadium precipitation of VO2(B) by hydrothermal method

The effect of iron, aluminum, silicon and phosphorus in the vanadium-rich solution on the vanadium precipitation of VO2(B) by hydrothermal method were studied. Through the analysis of vanadium conversation efficiency, the content of V and impurity elements in precipitates and their existing form, product crystal structure and micromorphology, it is concluded that the effect following the order of P > Fe > Si > Al. As the impurity concentration increased, V content of the precipitates decreased to varying degrees, while impurity content increased. The exist of Al, Si, Fe and P could alter the diffraction peaks intensity of some crystal faces and the micromorphology of VO2(B). The high concentrations of Fe and P transformed the VO2(B) to Fe2.5V7.1O16 and Na0.45VOPO4·1.58 H2O, respectively. V and P are easily combined by covalent bonds, affecting the precipitation of VO2(B). Silicon is adsorbed on the surface of the precipitate as silica gel, thereby reducing the purity of the precipitate. The influence of impurity elements in vanadium-rich solution on the precipitation of VO2(B) by hydrothermal method is studied, which will provide a theoretical basis for the application of the new process of vanadium precipitation by hydrothermal method.

Research on the Two-Pillar Solution and Its Implication

With the rapid development of economic globalization and digitalization, new business models are activating the world economy while exacerbating the remaining problems of base erosion and profit shifting (BEPS). In the face of intensifying international tax avoidance, The Organisation for Economic Co-operation and Development (OECD) has announced its Two-pillar solution to the international community, proposing a global minimum tax regime, which is effectively a coordination of global anti-tax avoidance measures. At present, Pillar 2 has come into effect, and Pillar 1 has also been opened for signature, marking the implementation stage of the two-pillar solution. In this paper, the two-pillar solution is the main research object. Firstly, from the perspective of large-scale tax avoidance by multinational corporations, this paper systematically analyzes the historical background of the introduction of the two-pillar solution of the OECD. After a detailed analysis of the provisions of the two-pillar solution, the existing institutional deficiencies and obstacles to its implementation are proposed. Finally, in response to the issues raised, practical recommendations are made that the elements of the two-pillar solution should aim to achieve general equity, balance the interests of developing countries and be in harmony with existing international tax policies. The governments should also optimize the structure of tax incentives.

Effects of solute alloying elements on solid solubility of TiC in austenite

Solute elements in microalloying steel affect the solid solubility of microalloying elements, and thus affect the second phase precipitation in steels. In this work, the influences of solid solution elements, especially Si and Al, on the solubility product of TiC in austenite were studied using the two-sublattice model. The results show that both Al and Si additions reduced the solubility product of TiC in the austenite region, and the reduction degree of TiC solubility product with Al addition was increased with increasing temperature, while it was decreased with Si addition. In addition, Mn, Mo and Cr additions all increased the solubility product of TiC in the austenite region, and the increment degree of TiC solubility product with Mo addition was decreased with increasing temperature, while it changed slightly with Mn or Cr addition with temperature. The model of solubility product of TiC without alloying additions in austenite was modified, and the calculating result was highly consistent with findings of literatures. Finally, a calculation model of TiC solubility product considering the influence of alloying elements was established.

Diffusion of radioactive waste elements from underground water and leachates of phosphate waste forms in pore solution of clay materials

Using through diffusion method at room temperature, migration of RW element simulators (P, Se, Br, Mo, Cs, U) in compacted samples of clay materials of various mineral compositions was studied during porous diffusion from model solutions: underground water and leachates of phosphate waste forms having a total salt content of up to 500 mg/L. Based on the results of experiments, effective diffusion coefficients and sorption distribution coefficients of elements in barrier materials were determined. Numerical models are proposed to describe diffusion transfer of selenium, cesium and uranium depending on porosity, mineral composition of materials, and concentration of elements in pore solution. Patterns of diffusion of elements from solutions of different salt composition were revealed.

The nitrogen deficiency influence on the growth and development of spring two-nuclear barley varieties grown under photoculture conditions

The purpose of the research is to study, the effect of N deficiency in irrigation solutions on the structural and functional characteristics of spring barley (Hordeum vulgare L.), the Oplot variety under controlled environmental conditions, in comparison with the structural and functional characteristics of Takmak barley, which has been the standard in all variety testing sites of the Krasnoyarsk Territory since 2022. The plants were grown under light culture conditions using hydroponics on expanded clay with constant environmental conditions at a photoperiod day/night of 17h / 7h, respectively. The basis for the preparation of irrigation solutions was Knop solution (control) and a solution in which, in order to reduce the concentration of N-NO3, the salt content was changed 2 times so as not to change the concentration of other macronutrients. A comparison of the rate of absorption of macronutrients by barley plants of the Oplot and Takmak varieties, depending on the composition of the irrigation solution, shows a higher demand of the barley of the Oplot variety for the presence of mineral nutrition elements in the irrigation solution in comparison with the barley of the Takmak variety. The deficiency of N in the irrigation solution led to a decrease in total tillering by about 2.5 times, but productive tillering in the barley of the Oplot variety decreased to a greater extent than in the barley of the Takmak variety. When growing on Knop solution the barley of the Oplot variety showed higher productivity than the barley of the Takmak variety. When grown on solutions with a deficiency of N, the grain yield of the barley of the Oplot variety decreased by 2.8 times, and in the barley of the Takmak variety, the differences between the control and experimental variants were unreliable. The barley of the Takmak variety showed higher resistance to N deficiency in the irrigation solution, thereby showing higher plasticity compared to the barley of the Oplot variety.

Adsorption of natural dye phycocyanin by means of Laponite®: Synthesis and characterization of the hybrid obtained

This work addresses the use of Laponite® clay in various applications, focusing on its adsorption capacity and improvement of properties in water-based products. It describes the synthesis of Laponite® hybrids with the pigmented cyanobacterium phycocyanin (PC) to evaluate the adsorption capacity of the dye. This research addresses the importance of Laponite® clay in improving rheological properties of water-based products due to its ability to interact with components in aqueous solutions. Laponite® can be effectively dispersed in water, enhancing the dispersion of other elements in solution and preventing aggregation of solids. The structure and properties of synthetic Laponite® are described, highlighting its use in the textile industry as an additive for pigments and the formation of gels. Experimentally, Laponite® is used to adsorb phycocyanin, a cyanobacterial pigment, with the aim of achieving maximum adsorption. A design of experiments with different experimental conditions, including pH, addition of silane and surfactant, is used. A detailed analysis of the characterization of the resulting hybrids is presented, including colour, total solar reflectance (TSR), thermal analysis (TGA), EDS, FTIR and X-ray diffraction (XRD) measurements. The results show successful adsorption of the pigment in all experiments, with adsorption percentages above 97%. The colour of the hybrids is evaluated and the total solar reflectance is analyzed, highlighting their importance in applications such as coatings and printed textiles. Infrared spectroscopy and X-ray diffraction are used to study the structural properties of the hybrids. For future work, it is intended to be able to apply the hybrids obtained on an industrial scale in the colouring of textiles and plastic polymers.

A non-uniform compound strip method for effective buckling analysis of stiffened structures

In this paper, a versatile compound strip method (CSM) with non-uniform spline functions is developed for buckling analysis of stiffened structures. The proposed method further extends the existing CSM by permitting the flexible modification of local knots to place the stiffeners along the strip arbitrarily. In addition, a reasonable knot arrangement can achieve an accurate solving procedure with improved convergence. The displacements of stiffeners are expressed compatibly by the fundamental parameters of skin according to the beam-plate model. Consequently, the reinforcement of stiffeners is naturally incorporated by adding the beam stiffness matrix to the corresponding strips. Based on the first-order shear deformation plate theory and non-uniform spline functions, the semi-analytical formulations of stiffened structures are established. The present method provides the possibility to achieve the local mesh refinement in the finite strip methods. The convergence and validation study is demonstrated through the comparisons with the results of the existing literature solution and finite element method. In conclusion, a more efficient and applicable CSM is proposed to analyze the buckling behaviors of stiffened structures.

Mn-controlled martensitic variant selection significantly affects the strength and toughness of 2.3 GPa ultra-high strength spring steel

In this study, the microstructure and mechanical properties of 55SiCrVNb ultra-high strength spring steel with 0.7 and 1.5 wt.% Mn were systematically investigated. The results show that 0.7Mn steel exhibited higher strength and toughness. The morphology and content of retained austenite, content of element in solid solution and the type and quantity of precipitates were basically the same in 0.7Mn and 1.5Mn steels. Hence, the variant reconstruction, as a unique perspective, was used to unravel the strengthening and toughening mechanisms governing the evolution of variants across varying Mn contents. Compared with the 1.5Mn steel, the decrease in Mn content deteriorated the variant selectivity (decreased variant frequency over 50 %), which led to a more uniform distribution of close-packed plane (CP) and Bain groups in 0.7Mn steel, thus refining the block size and improving the grain refinement strengthening (σp). The 0.7Mn steel with a higher density of high angle grain boundaries (HAGBs) effectively constrained dislocation slip, thereby enhancing dislocation strengthening (σd). As the Mn content decreased, the block size decreased from 0.24 to 0.14 μm, and the contribution of σp and σd increased by about 107 and 96 MPa, thus improving the yield strength. In addition, the increased HAGBs, which were dominated by the highly selective V1/V2, V1/V3(V5) and V1/V6 variant pairs, and the uniform CP and Bain group also contributed to inhibiting crack deflection and enhancing the impact toughness. Moreover, the higher Schmid factor with high geometrically necessary dislocation of 0.7Mn steel improved the deformation resistance of variants and strength. This work provided a new mechanism of strengthening and toughening dominated by variants.

(Invited) Degradation and Poisoning of Proton-Exchange Membrane Water Electrolyzer Anode Catalysts

Hydrogen production through water electrolysis is a crucial technology to enable the transition to a carbon neutral, hydrogen-based economy. One of the primary types of electrolyzers is the low-temperature proton-exchange membrane water electrolyzer (PEMWE). As with the analogous proton-exchange membrane fuel cells, platinum group metal electrocatalysts are utilized due to their activity and stability in acidic environment. Electrocatalysis R&D efforts for PEMWEs primarily focus on the oxygen evolution reaction (OER) since it is several orders of magnitude kinetically slower than the hydrogen evolution reaction (HER).1 Iridium-based metal oxides (IrOx) are regarded as the best PEM electrolyzer electrocatalysts as they balance activity and stability.2 However, improvements are needed in both areas to enable minimization of Ir loading to meet system cost targets while also meeting challenging performance and lifetime targets.3 An understanding of the factors affecting both the activity and stability of Ir-based OER catalysts is needed to develop strategies to enable both high OER activity and long-term stability of the PEMWE anode catalyst.This presentation will describe our studies of the effects of perfluorosulfonic acid (PFSA) binder on the OER kinetics and the factors influencing the stability of two commercial Ir-based OER catalysts, one comprised of IrOx only and the other also containing TiOx. Measurements of OER kinetics as a function of ionomer to catalyst ratio utilizing rotating disc electrode and cavity microelectrode methods in an acidic aqueous electrochemical environment will be described. Dissolution and loss of Ir under the operating conditions of the PEMWE anode is considered to be one of the main PEMWE anode degradation mechanisms.4 To understand the factors affecting this phenomenon, the potential and time-dependence of Ir (and Ti) were determined using an electrochemical flow cell system connected to an inductively-coupled plasma-mass spectrometer (ICP-MS) capable of detecting trace concentrations (<ppb) of dissolved elements in solution. The electrochemical data combined with the ICP-MS data have been used to evaluate the influence of various factors such as potential, potentiodynamic profile parameters (e.g., scan rate, upper and lower potential limits) on the dissolution processes in acidic aqueous electrolyte at room temperature.AcknowledgementsThis research is supported by the U.S. Department of Energy, Energy Efficiency and Renewable Energy, Hydrogen and Fuel Cell Technologies Office under the auspices of the H2NEW Consortium. Argonne National Laboratory is managed for the U.S Department of Energy by the University of Chicago Argonne, LLC, also under contract DE-AC-02-06CH11357.References A. Raveendran, M. Chandran, and R. Dhanusuraman, RSC Adv., 13 (2023) 3843.J. Ouimet, J.R. Glenn, D.D. Porcellinis, A.R. Motz, M. Carmo, K.E. Ayers, ACS Catalysis, 12 (2022) 6159."Technical Targets for Proton Exchange Membrane Electrolysis", U.S. Department of Energy, Energy Efficiency and Renewable Energy, Hydrogen and Fuel Cell Technologies Office, March, 2023.Zeng, R. Ouimet, L. Bonville, A. Niedzwiecki, C. Capuano, K. Ayers, A.P. Soleymani, J. Jankovic, H. Yu, R. Maric, et al., J. Electrochem. Soc., 169(5) (2022) 054536.

Investigating Corrosion Degradation of Porous Transport Layers for PEM Water Electrolyzers Using on-Line ICP-MS

The degradation of polymer electrolyte membrane water electrolyzer (PEMWE) is the net result of degradation phenomena across each component, which includes structural changes to the catalyst layer, deactivation of the electrolyte, loss of performance due to impurities in the feed water, and the corrosion and passivation of titanium-based bipolar plates (BPPs) and porous transport layers (PTLs).1, 2 This presentation will focus on PTL degradation, which has received relatively little attention compared to loss of performance related to catalyst and electrode degradation mechanisms. Generally, PTL degradation can be categorized into chemical/corrosion degradation and mechanical degradation. 3 In this work, we focus on corrosion degradation of the anode PTL. Titanium (Ti) is the state-of-the-art material for PTLs due to its stability and intrinsic electrical conductivity. Ti can however, develop an oxide layer in the harsh oxidizing conditions of the anode, thus reducing the effective electrical conductivity and cell performance. Coating the Ti parts with platinum group metals (Pt or Ir) is often used to protect against oxidation.4 An electrochemical flow cell system connected to an inductively-coupled plasma-mass spectrometer (ICP-MS) capable of detecting trace concentrations (<ppb) of dissolved elements in solution has been used to investigate the corrosion rates of the Ti-PTLs with and without coatings toward understanding factors influencing degradation mechanisms. The influence of various parameters such as potential, potentiodynamic profile parameters (e.g., scan rate, upper and lower potential limits), electrolyte type, and pH on the corrosion processes has been investigated. References Feng, X. Yuan, G. Liu, B. Wei, Z. Zhang, H. Li, H. Wang, J. Power Sources 2017, 366, 33.Babic, M. Suermann, F. N. Büchi, L. Gubler, T. J. Schmidt, J. Electrochem. Soc. 2017, 164, F387.Park, H. Oh, T. Ha, Y.I. Lee, K. Min, Appl. Energy 155 (2015) 866-880.Rakousky, U. Reimer, K. Wippermann, M. Carmo, W. Lueke, D. Stolten, J. Power Sources 326 (2016) 120–128. Acknowledgements This research is supported by the U.S. Department of Energy, Energy Efficiency and Renewable Energy, Hydrogen and Fuel Cell Technologies Office under the auspices of the H2NEW consortium. Argonne National Laboratory is managed for the U.S Department of Energy by the University of Chicago Argonne, LLC under contract DE-AC-02-06CH11357.

Electrical conductivity of binary magnesium alloys: Integrating first-principles and machine learning studies

The electrical conductivity is the fundamental physical property of Mg alloys and the basic information for the design of comprehensive high-performance Mg alloys. In this work, the electrical conductivity of 29 Mg-based binary alloys has been calculated using the first-principles methods and the main factors have been analyzed by machine learning. It is found that the electrical conductivity values of the binary alloys containing elements located in the s region and p region of the periodic table are bigger than others of alloys contain alloying elements in the f region and d region. The results of machine learning show that the difference ratio of volume (∆V/VMg), extra-nuclear electron configuration and difference of valence () play the main controlling role, followed by solid solubility and electronegativity of the alloying element. For solid solution elements in Mg-based binary alloys, the impact weight on the electrical conductivity is: difference ratio of volume > number of extra-nuclear electron vacancy > difference of valence.