Gas Transition Research Articles

Detecting Trace Gases at PPM Levels with Low Temperature Plasma Optical Emission Spectroscopy

Detecting Trace Gases at PPM Levels with Low Temperature Plasma Optical Emission Spectroscopy

The evolution of intra- and inter-molecular isotope equilibria in natural gases with thermal maturation

Naturally occurring hydrocarbon fluids in sedimentary basins have economic, geological and environmental significance. Connecting sedimentary basin temperature-time evolution with petroleum generation and transformation is a long-studied problem. In this study, we investigate the use of a novel tool – multiply substituted isotopologues of methane, for distinguishing between different chemical mechanisms in catagenesis and for characterizing the extent of thermal maturation of thermogenic natural gases. We analyze the stable isotope compositions of a suite of thermogenic gas samples that are globally distributed and cover a wide range in composition and thermal maturation, from dominantly unconventional shale gas formations and a few conventional gas plays. Our data show that methane generated at early thermal maturity has a stable isotope composition governed by chemical kinetics, characterized by a pronounced deficit in Δ12CH2D2; this signature can be explained by its formation chemistry that combines a more D-rich methyl radical pool and more D-poor H radical pool. Methane from higher thermal maturity fluids increases in Δ12CH2D2, reaching equilibrium at vitrinite reflectance maturity (Ro) of approximately 1.5% (equivalent to 170–210 °C peak burial temperature) and higher, which is interpreted to be the result of isotope exchange erasing the disequilibrium signature of catagenetic chemistry, mediated by CH activation during either radical chain reactions or organic-inorganic interactions on mineral surfaces. We further examined hydrogen isotope fractionations among methane, ethane and propane for a compiled global dataset and found that the intermolecular fractionation exhibits a trend similar to that seen for the Δ12CH2D2 value of methane, departing from equilibrium at low thermal maturities and moving towards equilibrium as maturity increases. These findings indicate that the inter- and intra-molecular hydrogen isotope structures of components of thermogenic natural gas transition from chemical-kinetic control at low thermal maturities toward thermodynamic control at higher thermal maturities, mediated by hydrogen exchange reactions. We propose that these systematic relationships could be used to identify the exact thermal maturation stages for natural gases and their associated fluids, especially for oil-associated gas at early maturation.

Graphene Formation through Pulsed Wire Discharge of Graphite Strips in Water: Exfoliation Mechanism.

This study aims to clarify the mechanism of exfoliation of graphene through electrical pulsed wire discharge (PWD) of a graphite strip, made by the compression of inexpensive expanded graphite in water. The explosion of the graphite strip was visualized using a high-speed video camera. During the energized heating of the sample, explosions, accompanied by shock waves due to expansion of gas inside the sample, occurred at various locations of the sample, and the sample started to expand rapidly. The exfoliated graphene was observed as a region with low light transmittance. The PWD phenomenon of graphite strips, a type of porous material, is reasonably explained by the change in electrical resistivity of the sample during discharge and the light emission due to energy transition of the excited gas.

Quantitative Analysis of Pharmaceutical Drugs Using a Combination of Acoustic Levitation and High Resolution Mass Spectrometry.

A combination of acoustic levitation, laser vaporization, and atmospheric pressure chemical ionization mass spectrometry (APCI-MS) is presented in this study that enabled sensitive analysis of pharmaceutical drugs from an aqueous sample matrix. An unfocused pulsed infrared laser provided contactless sample desorption from the droplets trapped inside an acoustic levitator by activation of the OH stretching band of aqueous and alcoholic solvents. Subsequent atmospheric pressure chemical ionization was used between the levitated droplet and the mass spectrometer for postionization. In this setup, the unfocused laser gently desorbed the analytes by applying very mild repulsive forces. Detailed plume formation studies by temporally resolved schlieren experiments were used to characterize the liquid gas transition in this process. In addition, the role of different additives and solvent composition was examined during the ionization process. The analytical application of the technique and the proof-of-concept for quantitative analysis were demonstrated by the determination of selected pharmaceutical drugs in aqueous matrix with limits of quantification at the lower nanomolar level and a linear dynamic range of 3-4 orders of magnitude.

Gas Transit Development in Europe and Beyond: In an Era of Geopolitical Influence and Climate Change Pressures

With the background of the political and geopolitical factors that determine where energy players can operate plus the complications that the pandemic has brought to operations and the change in energy demand, the article considers how to tackle gas transit development. In addition, it looks the development in light of the impact of the climate change challenge that conventional energy companies and investors are faced with and the resulting diversification needs. Lender reluctance to finance ‘dirty’ energy projects is changing the dynamics for investment. Gas is still promoted by significant industry players and lenders but as governments move towards their clean energy goals, access to funding for any non-renewable projects is looking to become more limited. Many industry players are still of the view that a renewable track cannot be built without a parallel track of gas supply to add to the energy mix. And indeed, the European Green Deal published in December 2019 introduces new ideas for the usage of existing gas infrastructure and there are still largescale cross-border natural gas pipelines under development and construction. The article addresses the steps that are needed to get a pipeline project from drawing board stage to implementation and operations. This is considered from a legal perspective, including looking at the ways in which to raise finance – through debt, equity and other funding sources. A focus of the article is the European Union Funding available to energy projects and how the policy is shaping the energy landscape. The upcoming regulatory changes relating to European Union financing instruments such as the Trans-European Networks for Energy Regulation (the “TEN-E”) which steers investment away from oil and gas pipelines and will offer financing opportunities for other types of smart grids and hydrogen and CO2 pipelines. It has been indicated that oil pipelines and electricity highways are to be removed as infrastructure categories and thematic areas and will no longer be suitable to be financed by the Connecting Europe Facility (“CEF”). Gas transit geopolitical climate change EU-funding

Observation of a non-Hermitian phase transition in an optical quantum gas.

Quantum gases of light, such as photon or polariton condensates in optical microcavities, are collective quantum systems enabling a tailoring of dissipation from, for example, cavity loss. This characteristic makes them a tool to study dissipative phases, an emerging subject in quantum many-body physics. We experimentally demonstrate a non-Hermitian phase transition of a photon Bose-Einstein condensate to a dissipative phase characterized by a biexponential decay of the condensate's second-order coherence. The phase transition occurs because of the emergence of an exceptional point in the quantum gas. Although Bose-Einstein condensation is usually connected to lasing by a smooth crossover, the observed phase transition separates the biexponential phase from both lasing and an intermediate, oscillatory condensate regime. Our approach can be used to study a wide class of dissipative quantum phases in topological or lattice systems.

Adsorption of Carbon Dioxide, Water Vapor, Nitrogen, and Sulfur Dioxide on Activated Carbon for Capture from Flue Gases: Competitive Adsorption and Selectivity Aspects

There is extensive interest in postcombustion flue gas treatment for mitigating CO2 emissions and removal of acid gases. In this study we investigate the adsorption of the main flue gas components (CO2, N2, SO2, and water vapor) on Filtrasorb 400 activated carbon to understand adsorption characteristics of the main components and competitive adsorption effects. The adsorption isotherms of the pure components of flue gas, CO2 (273.15–318.15 K and 0–50 bar), N2 (298.15–313.15 K and 0–150 bar), SO2 (273.15–303.15 K and 0–3.6 bar), and water vapor (293.15–303.15 K and 0–41 mbar), were investigated. The isosteric enthalpies of adsorption were determined to be a function of surface excess. The enthalpies at zero surface coverage have the order SO2 > H2O > CO2 > N2. However, the SO2 isosteric enthalpy decreases with increasing surface excess and is lower than that of water vapor at high surface excess uptake values. The temperature range for CO2 adsorption covers the subcritical to supercritical gas transition. There was no evidence for isosteric enthalpy differences over this temperature range. The adsorption kinetics for SO2 (290.65–303.15 K) and H2O (293.15–303.15 K) adsorption were measured for each isotherm pressure increment. In both cases the adsorption kinetics followed the linear driving force model. The adsorption mechanisms for both SO2 and H2O kinetic trends are discussed in terms of the adsorption mechanisms. The water vapor adsorption kinetics showed a minimum in the region where water molecules form clusters around functional groups, which merge in the pores. The SO2 adsorption kinetics also show a minimum with increasing surface coverage, and this is attributed to dipole–dipole interactions. The activation energies for diffusion of both SO2 and H2O into F400 were very low. Both the N2 and CO2 adsorption kinetics were too fast to be measured accurately by the gravimetric method used in this study. Ideal adsorbed solution theory (IAST) was used to calculate competitive adsorption of SO2/CO2 and CO2/N2 from the isotherms of the pure components. The competitive adsorption of CO2/N2 was investigated by using the integral mass balance (IMB) experimental method, and this was used for validation of the IAST. The results provide an insight into the role of competitive adsorption in the capture of CO2 and SO2 from flue gases by adsorption from both thermodynamic and kinetic perspectives.

Does ‘more’ equal ‘better’? – Analyzing the impact of diversification strategies on infrastructure in the European gas market

The paper investigates investments in gas infrastructure considering uncertainties in European gas markets. Furthermore, the study addresses the question of whether (more) diversification provides a (better) security of supply improvement. Thus, a stochastic optimization approach is introduced. The uncertainties focus on 2030 and 2045 in three dimensions, namely the Ukraine gas transit, future LNG prices, and the expected gas demand. Considering three diversification strategies, the model GAMAMOD-EU.sto optimizes investments in pipelines, LNG import terminals and gas storages as well as the gas dispatch. Results illustrate trade-offs between optimal gas supply and diversification strategies. Investments in pipelines to North African suppliers are made across all strategies, while the building of the Nord Stream 2 pipeline depend on the respective diversification strategy. Diversification through LNG quota changes the dispatch results significantly. Investments in storages are almost not necessary over all strategies, however, storages provide flexibility to prevent supply shortages, when diversification strategies are applied. Conclusion for policy makers regarding what is needed for preventing malinvestments and high costs in the European gas market are: an enhanced relationship between Russia and the EU and a clear vision on the role of gas in the future European energy system that reduces demand uncertainty.

Perturbative RG Analysis of the Condensate Dependence of the Axial Anomaly in the Three-Flavor Linear Sigma Model

Coupling of ‘t Hooft’s determinant term is investigated in the framework of the three-flavor linear sigma model as a function of the chiral condensate. Using perturbation theory around the minimum point of the effective action, we calculate the renormalization group flow of the first field-dependent correction to the coupling of the conventional UA(1) breaking determinant term. It is found that, at low temperatures, mesonic fluctuations make the anomaly increase when the chiral condensate decreases. As an application, we analyze the effect at the zero temperature nuclear liquid–gas transition.

Analysis of the AlN phase transition on a sapphire surface within a universal 2D lattice gas model in MBE

The AlN phase transition on the (0001) Al2O3 surface was investigated. It was experimentally estimated that the AlN formation rate as a function of temperature has a different character in two temperature regions. In the region of relatively low temperatures (T < 1210 K), the AlN formation rate is limited by chemical reactions. At higher temperatures (T > 1210 K), the formation of an ordered AlN phase is determined by a continuous two-dimensional phase transition within the filled AlN-lattice-gas cells formed on the sapphire surface. A three-parameter isotherm is proposed to describe the process. The observed phase transition in the AlN lattice gas is a continuous phase transition or a second-order transition.

Presidential Progress on Climate Change: Will the Courts Interfere With What Needs to Be Done to Save Our Planeet?

The Biden Administration is undertaking numerous actions to reduce greenhouse gas emissions and transition away from fossil fuels as part of the fight against climate change. Many of these actions are likely to be challenged in court. This paper describes the various legal theories that are likely to be used in these challenges, assesses their prospects of success given the current composition of the Supreme Court, and suggests ways to minimize the risks.

Beyond-mean-field description of a trapped unitary Fermi gas with mass and population imbalance

A detailed description is given of the phase diagram for a two-component unitary Fermi gas with mass and population imbalance, for both homogeneous and trapped systems. This aims at providing quantitative benchmarks for the normal-to-superfluid phase transition of a mass-imbalanced Fermi gas in the temperature-polarization parameter space. A self-consistent t-matrix approach is adopted, which has already proven to accurately describe the thermodynamic properties of the mass and population balanced unitary Fermi gas. Our results provide a guideline for the ongoing experiments on heteronuclear Fermi mixtures.

Tan\u2019s two-body contact across the superfluid transition of a planar Bose gas

Tan’s contact is a quantity that unifies many different properties of a low-temperature gas with short-range interactions, from its momentum distribution to its spatial two-body correlation function. Here, we use a Ramsey interferometric method to realize experimentally the thermodynamic definition of the two-body contact, i.e., the change of the internal energy in a small modification of the scattering length. Our measurements are performed on a uniform two-dimensional Bose gas of 87Rb atoms across the Berezinskii–Kosterlitz–Thouless superfluid transition. They connect well to the theoretical predictions in the limiting cases of a strongly degenerate fluid and of a normal gas. They also provide the variation of this key quantity in the critical region, where further theoretical efforts are needed to account for our findings.

Structural superfluid–Mott-insulator transition for a Bose gas in multirods

We report on a structural superfluid--Mott-insulator (SF-MI) quantum phase transition for an interacting one-dimensional Bose gas within permeable multirod lattices, where the rod lengths are varied from zero to the lattice period length. We use the ab initio diffusion Monte Carlo method to calculate the static structure factor, the insulation gap, and the Luttinger parameter, which we use to determine if the gas is a superfluid or a Mott insulator. For the Bose gas within a square Kronig-Penney (KP) potential, where barrier and well widths are equal, the SF-MI coexistence curve shows the same qualitative and quantitative behavior as that of a typical optical lattice with equal periodicity but slightly larger height. When we vary the width of the barriers from zero to the length of the potential period, keeping the height of the KP barriers, we observe a way to induce the SF-MI phase transition. Our results are of significant interest, given the recent progress on the realization of optical lattices with a subwavelength structure that would facilitate their experimental observation.

Борьба Украины за газовый транзит

Kiev's hopes for stopping the construction of the Nord Stream 2 gas pipeline were not achieved. As a result of the compromise reached between Berlin and Washington the construction was completed. The launch of the Nord Stream 2 can result in great losses for the Ukrainian state. Therefore, Ukraine continues to fight against the new northern route, hoping to prevent its launch or make its operation as difficult as possible. At the same time, the Kiev authorities are trying to secure guarantees for the preservation of Russian gas transit for another 15 years with the help of Western allies and to get compensation for the damage that will be caused to Ukraine in the event of a termination or a sharp reduction in gas transit.

Sustainable plastic waste management strategy: Optimization of plastic manufacturing plant waste (gas and product transition)

Production waste management has become the key to a sustainable manufacturing operation strategy. This study aims to analyse the waste gas and production waste from the polymerization process, especially the residual exhaust gas from the degassing unit and the final product from the product transition process that does not meet the requirements. Research using qualitative and quantitative methods. The analysis is done by calculating the amount of gas removed from the sweeping or degassing process and calculating the material balance of the production process to analyse the process loss. The results show that the largest contributor to the waste gas is from the degassing process and the pellets from the transition products. In addition, an optimization process is needed to recover exhaust gas with a recovery system and perform a trimming process or a mixing process to reduce the transition product to become prime product.

Украина: основные политические итоги года

In 2021 in Ukraine as a result of several objective reasons prerequisites were formed for a serious internal political crisis. Problems related to the shortage of energy resources may become a catalyst for negative processes in the economy and politics which will most likely lead to early parliamentary elections. In the south-east of the country, the Ukrainian leadership is deliberately escalating the conflict, which may lead to the resumption of active hostilities in the region. On the outer contour, Kiev’s Western partners continued a military development of Ukrainian territory, although they are still in no hurry to grant Ukraine the status of a full member of NATO. There have also been no changes in the country's relations with the European Union. Fearing the undesirable consequences of the launch of the Nord Stream 2, Kiev continued to actively fight for the preservation of gas transit through its GTS.

LIMITS OF TURKEY’S CAPABILITIES AS A TRANSIT GAS CORRIDOR

The paper examines the role of the Republic of Turkey as a transit corridor for the natural gas supply to the European Union. Turkey's interests in increasing its transit potential based on its favorable geographic location near gas producers and consumers are studied. The results achieved in this direction of the energy policy of the Republic of Turkey are brought out. The limitations for the increase of the volume of gas transit through the territory of Turkey are examined. The documents of the Ministry of Energy and Natural Resources of Turkey, the ongoing projects on the transit of pipeline gas through the Turkish territory are analyzed. It is shown that Turkey's interest in the expansion of the geography of gas imports and transit coincides with the interests of the European Union as a gas consumer as well as with the interest of gas suppliers in full (in the case of Azerbaijan) or partially (in the case of Russia) to transit gas through Turkey. Turkey's role as a transit gas corridor is limited by small volumes of gas in comparison with the other directions of supply and an increase in the share of LNG in the European gas market.

Multiphase feedback processes in the Sy2 galaxy NGC 5643

We study the multiphase feedback processes in the central ∼3 kpc of the barred Seyfert 2 galaxy NGC 5643. We used observations of the cold molecular gas (ALMA CO(2−1) transition) and ionized gas (MUSE IFU optical emission lines). We studied different regions along the outflow zone, which extends out to ∼2.3 kpc in the same direction (east-west) as the radio jet, as well as nuclear and circumnuclear regions in the host galaxy disk. The CO(2−1) line profiles of regions in the outflow and spiral arms show two or more different velocity components: one associated with the host galaxy rotation, and the others with out- or inflowing material. In the outflow region, the [O III]λ5007 Å emission lines have two or more components: the narrow component traces rotation of the gas in the disk, and the others are related to the ionized outflow. The deprojected outflowing velocities of the cold molecular gas (median Vcentral ∼ 189 km s−1) are generally lower than those of the outflowing ionized gas, which reach deprojected velocities of up to 750 km s−1 close to the active galactic nucleus (AGN), and their spatial profiles follow those of the ionized phase. This suggests that the outflowing molecular gas in the galaxy disk is being entrained by the AGN wind. We derive molecular and ionized outflow masses of ∼5.2 × 107 M⊙ (αCOGalactic) and 8.5 × 104 M⊙ and molecular and ionized outflow mass rates of ∼51 M⊙ yr−1 (αCOGalactic) and 0.14 M⊙ yr−1, respectively. This means that the molecular phase dominates the outflow mass and outflow mass rate, while the kinetic power and momentum of the outflow are similar in both phases. However, the wind momentum loads (Ṗout/ṖAGN) for the molecular and ionized outflow phases are ∼27−5 (αCOGalactic and αCOULIRGs) and &lt; 1, which suggests that the molecular phase is not momentum conserving, but the ionized phase most certainly is. The molecular gas content (Meast ∼ 1.5 × 107 M⊙; αCOGalactic) of the eastern spiral arm is approximately 50−70% of the content of the western one. We interpret this as destruction or clearing of the molecular gas produced by the AGN wind impacting in the eastern side of the host galaxy (negative feedback process). The increase in molecular phase momentum implies that part of the kinetic energy from the AGN wind is transmitted to the molecular outflow. This suggests that in Seyfert-like AGN such as NGC 5643, the radiative or quasar and the kinetic or radio AGN feedback modes coexist and may shape the host galaxies even at kiloparsec scales through both positive and (mild) negative feedback.

Cooperation and Security: Examining the Political Discourse on Natural Gas Transit in Ukraine and Slovakia

The COVID-19 pandemic appeared in the midst of developing the European Green Deal, the most ambitious project to decarbonise the EU’s economy to date. Among other issues, the project highlighted the challenges connected to the long-term role of natural gas as a fossil fuel in the European economy. Moreover, the changes to the gas architecture caused by the development of new import infrastructure (especially Nord Stream and its extension, which is currently under construction) put additional pressure on the transit countries, mainly of which are linked to the Brotherhood pipeline. These have been strong supporters of natural gas utilisation and harsh critics of new pipelines that circumvent their territories, as they consider energy transit to be an important part of their energy sectors. This research examines the political discourse on gas transit in Slovakia and Ukraine in order to identify the main arguments connected to these positions. The paper examines a total of 233 textual units from both countries for the period 2014–2018. It concludes that, while Ukraine sees transit predominantly through the lens of cooperation with the EU and other actors, the Slovak political discourse considers gas transit in terms of energy security and the availability of gas for the national economy.