Local Hydrogen Research Articles

Multiplexed Conformationally Selective, Localized Gas-Phase Hydrogen Deuterium Exchange of Protein Ions Enabled by Transmission-Mode Electron Capture Dissociation.

In this article, we present an approach for conformationally multiplexed, localized hydrogen deuterium exchange (HDX) of gas-phase protein ions facilitated by ion mobility (IM) followed by electron capture dissociation (ECD). A quadrupole-IM-time of flight instrument previously modified to enable ECD in transmission mode (without ion trapping) immediately following a mobility separation was further modified to allow for deuterated ammonia (ND3) to be leaked in after m/z selection. Collisional activation was minimized to prevent deuterium scrambling from giving structurally irrelevant results. Gas-phase HDX with ECD fragmentation for exchange site localization was demonstrated with the extensively studied protein folding models ubiquitin and cytochrome c. Ubiquitin was ionized from conditions that stabilize the native state and conditions that stabilize the partially folded A-state. IM of deuterated ubiquitin 6+ ions allowed the separation of more compact conformers from more extended conformers. ECD of the separated subpopulations revealed that the more extended (later arriving) conformers had significant, localized differences in the amount of HDX observed. The 5+ charge state showed many regions with protection from HDX, and the 11+ charge state, ionized from conditions that stabilize the A-state, showed high levels of deuterium incorporation throughout most of the protein sequence. The 7+ ions of cytochrome c ionized from aqueous conditions showed greater HDX with unstructured regions of the protein relative to interior, structured regions, especially those involved in heme binding. With careful tuning and attention to deuterium scrambling, our approach holds promise for determining region-specific information on a conformer-selected basis for gas-phase protein structures, including localized characterizations of ligand, epitope, and protein-protein binding.

Hydrogen bonding structure and dynamics of cis- and trans- conformers of N-methylformamide in water, DMSO and water-DMSO mixtures at varying compositions

The local hydrogen bonding structure and dynamics of cis- and trans- N-methylformamide (NMF) in water, DMSO and in water–DMSO mixture is investigated by classical molecular dynamics simulations. We have considered five different concentrations of NMF in water as well as in DMSO at 298 K. In the case of NMF (XNMF = 0.20) in water–DMSO mixtures, we have considered six different concentrations, varying from NMF in pure water to DMSO. It is observed that the donating ability of amide–hydrogen of NMF to the oxygen of DMSO is higher compared to the oxygen of water. The variation of DMSO shows negligible effects on the HNMF…ODMSO radial distribution function (RDF), whereas the HNMF…OWAT decreases with the addition of water to the solution. In the case of NMF in water–DMSO mixtures, the addition of DMSO strengthens the HNMF…ODMSO as well as HNMF…OWAT correlation, but it differently affects for cis- and trans- NMF in the solution. DMSO prefers cis- conformer, whereas water prefers trans- NMF. In NMF–water–DMSO mixtures, the addition of DMSO strengthens HWAT…ONMF up to intermediate DMSO concentration, but at very high DMSO concentration, it decreases due to preferable HNMF…ODMSO interaction. The probability of hydrogen bonding between NMF–NMF is higher in NMF–DMSO solution compared to NMF–water. The dynamical slowdown is observed for all the species in water–NMF mixtures at intermediate concentration, whereas in the case of NMF–DMSO solution, faster dynamics are observed with the addition of DMSO. For NMF in water–DMSO mixtures, the dynamical slowdown is observed as DMSO is added to the NMF–water solution. Our calculated hydrogen-bond lifetime suggested that the DMSO forms a stronger hydrogen bond with cis-NMF whereas water generally prefers trans-NMF.

Current Status and Outlook of Temporary Implants (Magnesium/Zinc) in Cardiovascular Applications

Medical application materials must meet multiple requirements, and the designed material must mimic the structure, shape. and support the formation of the replacing tissue. Magnesium (Mg) and Zinc alloys (Zn), as a “smart” biodegradable material and as “the green engineering material in the 21st century”, have become an outstanding implant material due to their natural degradability, smart biocompatibility, and desirable mechanical properties. Magnesium and Zinc are recognized as the next generation of cardiovascular stents and bioresorbable scaffolds. At the same time, improving the properties and corrosion resistance of these alloys is an urgent challenge. particularly to promote the application of magnesium alloys. A relatively fast deterioration rate of magnesium-based materials generally results in premature mechanical integrity compromise and local hydrogen build-up, resulting in restricted applicability. This review article aims to give a comprehensive comparison between Zn-based alloys and Mg-based alloys, focusing primarily on degradation and biocompatibility for cardiovascular applications. The recent clinical trials using these biodegradable metals have also been addressed.

Concurrent 21. Presentation for: Conceptual model of the Lower Permian Kingia Sandstone (northern Perth Basin, Western Australia) as an alternative energy resource

Presented on Thursday 19 May: Session 21 The geothermal potential of the Kingia aquifer in the northern Perth Basin has been identified. In order to further assess resource potential, the occurrence, conditions, and properties of the Kingia Sandstone have been considered further. A new regional correlation supports the Kingia Sandstone being a regionally extensive unit deposited along the northern margin of the syn-depositional Dandaragan Trough. The unit is part of a falling-stage to lowstand system containing lower and upper shoreface, coastal, beach, and estuarine sands. Gross Kingia Sandstone thickness varies from 16 m on flanking terraces to at least 71 m in the basin depocenter. At depth, reservoir properties are preserved where iron-rich clay grain coatings inhibit cementation and preserve primary porosity. In such cases, net reservoir ranges from 3 to 58 m thick (18 m mean) and net porosity range is 12–19 p.u. (15 p.u. mean). The prevailing geothermal gradient is ~37°C/km with heat flow in excess of 90 mW/m2. Resultant Kingia aquifer temperatures exceed 115°C. Given the presence of hot, porous Kingia aquifer, the potential for geothermal power generation is strong. Production of Kingia brine to surface facilities allows for power conversion via established binary Organic Rankine Cycle (ORC) technology. A scalable Kingia opportunity could help to meet Western Australia’s decarbonisation aspirations by contributing to the replacement of coal-fired and gas-fired power plants, plus supply of low-carbon power to local urea, hydrogen, and gas projects. An enhanced understanding of Kingia porosity distribution, reservoir compartmentalisation, flow performance, and ultimate energy delivery remain key uncertainties subject to future de-risking activities. To access the presentation click the link on the right. To read the full paper click here

Concurrent 2. Presentation for: Zero emissions LNG – a credible opportunity for the industry

Presented on Tuesday 17 May: Session 2 Australia is vying with Qatar to be the top global liquefied natural gas (LNG) exporter, with the Australian LNG industry earning around A$17 billion annually and employing over 50 000 people. But where is the LNG industry headed as we move towards a zero emissions global energy economy? This paper presents a credible road map for the industry to transition to a zero emissions industry across the whole value chain. It addresses the steps being taken to reduce fugitive emissions, beneficially use the CO2 extracted from natural gas streams, electrify the operation of liquefaction facilities, use zero emissions fuels for LNG shipping whilst recovering boil-off gas, capture and beneficially use solid inert carbon from the methane at the LNG destination country then distribute, and burn hydrogen making the whole process zero emissions. One of the main benefits of this pathway is that most of the infrastructure required already exists reducing the capital investment required, hence improving the economics. This paper examines the viability and technical maturity of each stage of this road map against other potential zero emissions technologies. Japan is one of Australia’s largest LNG customers and has committed to building a local hydrogen economy so has been used as the basis for the economic comparisons studied. To access the presentation click the link on the right. To read the full paper click here

Numerical Simulation and Modeling of Hydrogen Gas Evolution on Planar and Microwire Array Electrodes

The impact of gas evolution on the electrochemical characteristics of planar electrodes and microwire array electrodes has been analyzed using modeling and simulation. The impacts can mainly be broken into three phenomena: a) a shift in the local reversible hydrogen electrode potential; b) hyperpolarization; and c) an increase in the solution resistance of the electrolyte. The local reversible hydrogen electrode potential shift was found to play the most important role, constituting >40% of the total potential drop between the cathode and reference electrode, following correction for cell resistance. Compared to planar electrodes, a microwire array structure reduces the impact of bubbles on the solution conductance, but the shift in the local reversible hydrogen electrode potential varies with distance from the actual electrode surface.

The Earth’s Outer Exospheric Density Distributions Derived From PROCYON/LAICA UV Observations

AbstractCurrent three‐dimensional, data‐based models for the terrestrial exosphere have been derived from measurements of optically thin Lyman‐alpha (Ly‐α) emissions scattered by neutral hydrogen atoms. Such models are only valid for the middle exospheric region (3–8 Earth radii geocentric distances) since the orbital paths of the space‐based platforms used to acquire Ly‐α radiance were located within the exosphere, thus precluding the proper detection of the faint outer exospheric emission. Notwithstanding, accurate specifications of density distributions beyond 8 RE are needed to support comprehensive studies of the solar‐terrestrial interactions. Two upcoming missions, the Solar wind Magnetosphere‐Ionosphere Link Explorer and the Lunar Environment Heliospheric X‐ray Imager, will image the Earth’s magnetosheath in soft X‐rays, and neutral densities are crucial to extract ion distributions through inversion of the acquired images. This work develops a technique to estimate the Earth’s outer exospheric density distributions using far‐ultraviolet wide‐field data acquired by the Lyman‐Alpha Imaging Camera (LAICA) onboard the Proximate Object Close Flyby with Optical Navigation mission. Our approach formulates an inverse problem based on the linearity between measurements of scattered Ly‐α flux and the local atomic hydrogen density, which is solved using the Bayesian approach known as Maximum a posteriori estimation. We use the LAICA image to derive global, 3‐D hydrogen density distributions at 6–20 RE geocentric distances. We find that the spatial structure of the outer exosphere agrees well with the predictions of radiation pressure theory. Further, we find that the hydrogen density at the 10 RE subsolar point is 26.51 atoms/cm3.

Parametric study highlighting cooler and spray activation on the transient mixing of a three-gas composition in the PANDA facility

In postulated accident scenarios with the release of steam and hydrogen in the containment, for some nuclear power plant designs it is foreseen that sprays and coolers are activated to condense steam and mitigate the containment pressure build-up. The operation of the sprays and the coolers induce flow with the effect of mixing a stratified atmosphere which reduces local hydrogen concentration. However, steam condensation could lead to the formation of combustible air-hydrogen mixtures. Therefore, for the management of a severe accident, it is crucial to know the overall effect of spray and cooler activation on the containment pressure history and gas-mixture concentration evolution. In this article, the results of a series of five experiments, identified as HP4 (HYMERES PANDA series 4) series, are presented. The HP4 series was part of the OECD/NEA HYMERES project, and the main objective was to investigate the combined effect of a cooler and a spray in the containment atmosphere. The HP4 series was performed in the large-scale thermal-hydraulic facility PANDA facility (PSI, Switzerland). In the HP4 test matrix, the cooler design (with cooling tube partially or fully enclosed in a cooler case) and the spray design (full cone or hollow cone nozzle) were varied. Moreover, the spray water temperature was an additional parameter. The HP4 series revealed that the containment pressure history and the gas mixture composition during the postulated scenarios are strongly affected by spray and cooler safety systems whereas the details of the spray and cooler design are of minor importance.The containment pressure during the experiments increased from atmospheric up to 2.5 bar and maximum power removed by the cooler was about 100 KW. The spray activation induced steam condensation and the highest de-pressurization induced by the combined spray and cooler operation was about 0.7 bar, i.e. from 2.5 bar to 1.8 bar.

Conceptual model of the Lower Permian Kingia Sandstone (northern Perth Basin, Western Australia) as an alternative energy resource

The geothermal potential of the Kingia aquifer in the northern Perth Basin has been identified. In order to further assess resource potential, the occurrence, conditions, and properties of the Kingia Sandstone have been considered further. A new regional correlation supports the Kingia Sandstone being a regionally extensive unit deposited along the northern margin of the syn-depositional Dandaragan Trough. The unit is part of a falling-stage to lowstand system containing lower and upper shoreface, coastal, beach, and estuarine sands. Gross Kingia Sandstone thickness varies from 16 m on flanking terraces to at least 71 m in the basin depocenter. At depth, reservoir properties are preserved where iron-rich clay grain coatings inhibit cementation and preserve primary porosity. In such cases, net reservoir ranges from 3 to 58 m thick (18 m mean) and net porosity range is 12–19 p.u. (15 p.u. mean). The prevailing geothermal gradient is ~37°C/km with heat flow in excess of 90 mW/m2. Resultant Kingia aquifer temperatures exceed 115°C. Given the presence of hot, porous Kingia aquifer, the potential for geothermal power generation is strong. Production of Kingia brine to surface facilities allows for power conversion via established binary Organic Rankine Cycle (ORC) technology. A scalable Kingia opportunity could help to meet Western Australia’s decarbonisation aspirations by contributing to the replacement of coal-fired and gas-fired power plants, plus supply of low-carbon power to local urea, hydrogen, and gas projects. An enhanced understanding of Kingia porosity distribution, reservoir compartmentalisation, flow performance, and ultimate energy delivery remain key uncertainties subject to future de-risking activities.

Zero emissions LNG – a credible opportunity for the industry

Australia is vying with Qatar to be the top global liquefied natural gas (LNG) exporter, with the Australian LNG industry earning around A$17 billion annually and employing over 50 000 people. But where is the LNG industry headed as we move towards a zero emissions global energy economy? This paper presents a credible road map for the industry to transition to a zero emissions industry across the whole value chain. It addresses the steps being taken to reduce fugitive emissions, beneficially use the CO2 extracted from natural gas streams, electrify the operation of liquefaction facilities, use zero emissions fuels for LNG shipping whilst recovering boil-off gas, capture and beneficially use solid inert carbon from the methane at the LNG destination country then distribute, and burn hydrogen making the whole process zero emissions. One of the main benefits of this pathway is that most of the infrastructure required already exists reducing the capital investment required, hence improving the economics. This paper examines the viability and technical maturity of each stage of this road map against other potential zero emissions technologies. Japan is one of Australia’s largest LNG customers and has committed to building a local hydrogen economy so has been used as the basis for the economic comparisons studied.

Numerical study on effect of inclusions on hydrogen segregation in steel under stress conditions

It is generally believed that hydrogen embrittlement (HE) of metallic material is closely related to the presence of hydrogen traps such as inclusions inside. Therefore, the study of hydrogen segregation in the inclusions is essential for the further understanding of the mechanism of HE phenomena. In this study, a numerical model for exploring the hydrogen transport and hydrogen segregation in inclusions under stress conditions was developed, and the effect of inclusion's shape and orientation, micro-cracks and stress magnitude on hydrogen segregation was investigated. Results showed that, inclusion's shape made a great effect on the hydrogen concentration at the inclusions/matrix interface, which became higher as inclusion closed to a globular shape. The hydrogen concentration inside the inclusions was affected by both the shape of inclusions and the angle between the orientation of inclusions and the hydrogen diffusion direction. The hydrogen segregation in inclusions with micro-cracks was much greater than that without micro-cracks, which caused 3–4 times local hydrogen concentration increase in inclusions, leading to the enhancement of HE susceptibility of the steel. The magnitude of stress did not change the regions of hydrogen segregation, but the hydrogen concentration at each region increased with the increasing stress.

Local fracture criterion for quasi-cleavage hydrogen-assisted cracking of tempered martensitic steels

Electrochemical permeation cell built on a Instron tensile testing machine allows fracturing notched specimens under hydrogen flux while monitoring simultaneously the flow stress and the permeation anodic current. Analysis of the fracture surfaces reveals that cracking initiates at the hydrogen-entry surfaces as quasi-cleavage regions followed by ductile propagation. Quasi-cleavage zones were fully developed at the maximum engineering stress and often initiate around inclusions for unnotched specimens. The observation of multiple cracks at the hydrogen-entry surfaces and correlations between quasi-cleavage features and martensitic boundaries suggest that cracking is related to decohesion of cropping out and inner boundaries. The local mechanical states and diffusible hydrogen concentration and flux at quasi-cleavage failure were calculated by finite element method (FEM). The results predict local failure criteria in terms of decrease of local maximum principal stress and equivalent plastic strain with local diffusible hydrogen concentration, revealing that the inclusion of hydrogen-mechanical-structural interactions at the charging surfaces is necessary to complete fracture analysis.

Fiber optic localized surface plasmon resonance hydrogen sensor based on gold nanoparticles capped with palladium

We propose an optical fiber-based localized surface plasmon resonance sensor to overcome limitations with hydrogen gas explosions in various types of hydrogen sensors and minimize human damage caused by exposure to hazardous environments. For selective detection of hydrogen, a simple palladium-capping process was applied on a fiber-optic localized surface plasmon resonance. After the palladium-capping, the sensor was exposed to various refractive index solutions to confirm the linearity of the response. Hydrogen gas reactivity was measured at concentrations from 0.8% to 4%; the reaction time at each concentration was observed as 116 s until the signal stabilized. The coefficient of variation (CV) and limit of detection (LOD) were calculated based on the results obtained through repeated measurements. The reproducibility was verified with an average CV of 11%. In addition, the developed sensor showed a low LOD of 0.086%. The hysteresis characteristic was observed within 1% in the output change, which was similar to the fluctuation range allowed by the light source per time. The proposed sensor based on the optical principle is expected to reduce the risk of explosions and has advantages in a simple configuration and low-cost production based on optical fiber.

A Conservative Approach for the Fast Deflagration Analysis in the Containment With GASFLOW-MPI

The nuclear regulation authorities of many countries require that the containment remains its integrity for a local hydrogen risk during any possible accident conditions. Therefore, the combustion consequence should be analyzed to demonstrate that the containment integrity is not being challenged for the hydrogen risk when the flame acceleration risk cannot be safely ruled out. Considering the uncertainties of both the combustion model and severe accident analysis, the criteria and experimentally based combustion (CREBCOM) model is adopted to provide a conservative result for pressure and the thermal load for combustion analyses in this study. Firstly, the CREBCOM is developed in the GASFLOW-MPI code and validated with the RUT experiment. The result shows that the CREBCOM model can provide a reliable overpressure for the choking regime combustion. Then, this model is adopted for the hydrogen safety analysis for the Advanced Pressurized Water Reactor (PWR) 1000. The hydrogen distribution is calculated with the mass and energy release obtained from severe accident analysis, from which, the most unfavorable ignition time and location is selected. The result of the CREBCOM model is compared with that of the turbulent flame closure model, which is a commonly used model for combustion analysis in containment safety. The results show that the CREBCOM model can provide a conservative prediction for the pressure and thermal load of combustion. Therefore, the CREBCOM model with the sonic flame assumption is applicable for the FA risk analysis in a local compartment for nuclear containments where a sonic deflagration cannot be safely excluded and manages to obtain a conservative pressure and thermal load for further evaluation on the containment integrity.

Selectively Altering the Reactivity of Transient Organic Radical Ions via Their Solvation Environment.

Photoexcitation of the charge transfer band of electron donor-acceptor complexes composed of toluene and 1,2,4,5-tetracyanobenzene yields organic radical ion pairs whose ultrafast reactive dynamics are determined by equilibrium solvent properties. A comparative study of ultrafast reaction rates in a series of alkane alcohols identified their dependence on the local polarizability and hydrogen bond donating/accepting character of the solvent. Because of the rapid and efficient equilibration of these radical ion pairs into solvent-separated species, simple modifications to bulk conditions can be used as a means to selectively alter their decay rates. Selectively altering distinct stages in this photochemical cycle via cosolutes or additives is a valuable step toward understanding and controlling the reactivity of organic radical ions in complex environments.

Implementation of an experimental setup to qualitatively detect hydrogen permeation along grain boundaries in nickel using Scanning Kelvin Probe Force Microscopy under varying atmospheres

The full understanding of the mechanisms of hydrogen embrittlement requires the knowledge of the local hydrogen distribution. One of the microstructural features where hydrogen segregates are grain boundaries, which is then responsible for the transition from transgranular to intergranular fracture. Furthermore, the type of grain boundary influences the segregated hydrogen and its diffusion rates. A tool to measure local hydrogen contents qualitatively, and maybe quantitatively in the future, is Scanning Kelvin Probe Force Microscopy (SKPFM). In this work, we use SKPFM to detect hydrogen at grain boundaries in situ in a permeation setup. The influence of the operation mode as well as the atmosphere on the Contact Potential Difference VCPD is investigated in an in house atmosphere chamber. The atmosphere has a strong influence on VCPD, especially the relative humidity, which is important if the method is to be used quantitatively in the future. We propose to use low oxygen contents and high relative humidities for these SKPFM measurements.

Numerical analysis on in-core ignition and subsequent flame propagation to containment in OPR1000 under loss of coolant accident

Since Fukushima nuclear power plant (NPP) accident in 2011, the importance of research on various severe accident phenomena has been emphasized. Particularly, detailed analysis of combustion risk is necessary following the containment damage caused by combustion in the Fukushima accident. Many studies have been conducted to evaluate the risk of local hydrogen concentration increases and flame propagation using computational code. In particular, the potential for combustion by local hydrogen concentration in specific areas within the containment has been emphasized. In this study, the process of flame propagation generated inside a reactor core to containment during a loss of coolant accident (LOCA) was analyzed using MELCOR 2.1 code. Later in the LOCA scenario, it was expected that hydrogen combustion occurred inside the reactor core owing to oxygen inflow through the cold leg break area. The main driving force of the oxygen intrusion is the elevated containment pressure due to the molten corium–concrete interaction. The thermal and mechanical loads caused by the flame threaten the integrity of the containment. Additionally, the containment spray system effectiveness in this situation was evaluated because changes in pressure gradient and concentrations of flammable gases greatly affect the overall behavior of ignition and subsequent containment integrity.

Pore-scale dynamics for underground porous media hydrogen storage

Underground hydrogen storage (UHS) has been launched as a catalyst to the low-carbon energy transitions. The limited understanding of the subsurface processes is a major obstacle for rapid and widespread UHS implementation. We use microfluidics to experimentally describe pore-scale multiphase hydrogen flow in an aquifer storage scenario. In a series of drainage-imbibition experiments we report the effect of capillary number on hydrogen saturations, displacement/trapping mechanisms, dissolution kinetics and contact angle hysteresis. We find that the hydrogen saturation after injection (drainage) increases with increasing capillary number. During hydrogen withdrawal (imbibition) two distinct mechanisms control the displacement and residual trapping – I1 and I2 imbibition mechanisms, respectively. Local hydrogen dissolution kinetics show dependency on injection rate and hydrogen cluster size. Dissolved global hydrogen concentration corresponds up to 28% of reported hydrogen solubility, indicating pore-scale non-equilibrium dissolution. Contact angles show hysteresis and vary between 17 and 56° Our results provide key UHS experimental data to improve understanding of hydrogen multiphase flow behaviour.

Policy analysis of local hydrogen energy and fuel cell vehicles based on CA

ABSTRACT Based on content analysis (CA), this paper, starting from industrial chain and value chain, constructs a two-dimensional analysis model of the policy tool-industrial chain and policy tool-value chain, respectively. A text analysis of policy documents related to hydrogen energy and fuel cell automobile industry in major areas made before December 2020 shows that environmental policy tools are mostly employed, followed by the demand side and the supply side. Specifically, local policy tools mainly act on the infrastructure links of the industrial chain and the use links of the value chain, accounting for 42.30% and 42.89%, respectively, aiming to demonstrate and promote hydrogen energy and fuel cell vehicles. The policy focus shows a shift from the environment to the demand side. It is necessary to implement supply-oriented policies, optimise the internal structure of policy types, and strengthen the coordination between policy tools, industrial chain and value chain.

Model description of hydrogen-induced damage evolution in high-strength steel weld metal based on results of a novel test method

In this paper, the development of a novel method for testing welded tensile specimens under two-stage external tensile loading is presented. The test method is intended to investigate the susceptibility of submerged arc welded high-strength steel specimens of type S690QL-S3Ni2.5CrMo to hydrogen-induced damage. Multiple cracking events within one specimen prove that the locally prevailing boundary conditions decisively determine the hydrogen-induced damage sequences.By means of SEM and EBSD analyses on specimens after test completion, interrelationships about the microstructural damage behavior are being examined. The crack tip environments are of particular importance here, since complex stress and strain conditions tend to cause hydrogen accumulation and further propagation of inter- and transgranular cracks here. In the vicinity of crack tips, retained austenite is of special importance. This metastable phase might undergo a deformation-induced transformation into crack-sensitive martensite and simultaneously release high local hydrogen contents as a former hydrogen trap. Finally, a model description including various sections of the stress- and hydrogen-induced damage evolution is derived from the empirical-analytical results.