AbstractThis review paper provides a critical examination of underground hydrogen storage (UHS) as a viable solution for large-scale energy storage, surpassing 10 GWh capacities, and contrasts it with aboveground methods. It exploes into the challenges posed by hydrogen injection, such as the potential for hydrogen loss and alterations in the petrophysical and petrographic characteristics of rock structures, which could compromise the efficiency of UHS systems. Central to our analysis is a detailed overview of hydrogen solubility across various solvents, an extensive database of potential mineralogical reactions within underground storage environments, and their implications for hydrogen retention. We particularly focus on the effects of these reactions on the porosity of reservoir and cap rocks, the role of diffusion in hydrogen loss, and the consequences of multiphase flow induced by hydrogen injection. Our findings highlight the critical mineralogical reactions—specifically, goethite reduction and calcite dissolution—and their pronounced impact on increasing cap rock porosity. We underscore a notable discovery: hydrogen's solubility in non-aqueous phases is significantly higher than in aqueous phases, nearly an order of magnitude greater. The paper not only presents quantitative insights into the mechanisms of hydrogen loss but also pinpoints areas in need of further research to deepen our understanding of UHS dynamics. By identifying these research gaps, we aim to guide future studies towards enhancing the operational efficiency and safety of UHS facilities, thereby supporting the transition towards sustainable energy systems. This work is pivotal for industry stakeholders seeking to optimize UHS practices, ensuring both the effective utilization of hydrogen as a clean energy carrier and the advancement of global sustainable energy goals.
Combined analyses of the Higgs boson production and decay rates as well as its coupling strengths to vector bosons and fermions are presented. The combinations include the results of the analyses of the H → γγ, ZZ∗, WW∗, Zγ, bb, ττ and μμ decay modes, and the constraints on the associated production with a pair of top quarks and on the off-shell coupling strengths of the Higgs boson. The results are based on the LHC proton-proton collision datasets, with integrated luminosities of up to 4.7 fb-1 at √S =7 TeV and 20.3 fb-1 at √S = 8 TeV, recorded by the ATLAS detector in 2011 and 2012. Combining all production modes and decay channels, the measured signal yield, normalised to the Standard Model expectation, is 1.18+0.15 -0.14. The observed Higgs boson production and decay rates are interpreted in a leading-order coupling framework, exploring a wide range of benchmark coupling models both with and without assumptions on the Higgs boson width and on the Standard Model particle content in loop processes. The data are found to be compatible with the Standard Model expectations for a Higgs boson at a mass of 125.36 GeV for all models considered.
We have used pH-, Na-, and Cl-sensitive microelectrodes to study basolateral HCO3- transport in isolated, perfused proximal tubules of the tiger salamander Ambystoma tigrinum. In one series of experiments, we lowered basolateral pH (pHb) from 7.5 to 6.8 by reducing [HCO3-]b from 10 to 2 mM at a constant pCO2. This reduction of pHb and [HCO3-]b causes a large (approximately 0.35), rapid fall in pHi as well as a transient depolarization of the basolateral membrane. Returning pHb and [HCO3-]b to normal has the opposite effects. Similar reductions of luminal pH (pHl) and [HCO3-]l have only minor effects. The reduction of [HCO3-]b and pHb also produces a reversible fall in aiNa. In a second series of experiments, we reduced [Na+]b at constant [HCO3-]b and pHb, and also observed a rapid fall in pHi and a transient basolateral depolarization. These changes are reversed by returning [Na+]b to normal. The effects of altering [Na+]l in the presence of HCO3-, or of altering [Na+]b in the nominal absence of HCO3-, are substantially less. Although the effects on pHi and basolateral membrane potential of altering either [HCO3-]b or [Na+]b are largely blocked by 4-acetamido-4-isothiocyanostilbene-2,2'-disulfonate (SITS), they are not affected by removal of Cl-, nor are there accompanying changes in aiCl consistent with a tight linkage between Cl- fluxes and those of Na+ and HCO3-. The aforementioned changes are apparently mediated by a single transport system, not involving Cl-. We conclude that HCO3- transport is restricted to the basolateral membrane, and that HCO3- fluxes are linked to those of Na+. The data are compatible with an electrogenic Na/HCO3 transporter that carries Na+, HCO3-, and net negative charge in the same direction.