Journal articles: 'Gas standard generation'

1

Xiong, Guohua, and Janusz Pawliszyn. "Microwave-Assisted Generation of Standard Gas Mixtures." Analytical Chemistry 74, no. 10 (May 2002): 2446–49. http://dx.doi.org/10.1021/ac015671+.

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Rodinkov, O. V., I. N. Rachkovskii, and L. N. Moskvin. "Chromatomembrane gas extraction generation of standard gas mixtures using composite carbon-fluoroplastic matrices." Journal of Analytical Chemistry 63, no. 9 (August 20, 2008): 857–62. http://dx.doi.org/10.1134/s1061934808090104.

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Kryukov, R. E., V. F. Goryushkin, Yu V. Bendre, L. P. Bashchenko, and N. A. Kozyrev. "Thermodynamic aspects of Cr₂O₃ reduction by carbon." Izvestiya. Ferrous Metallurgy 62, no. 12 (January 15, 2020): 950–56. http://dx.doi.org/10.17073/0368-0797-2019-12-950-956.

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In order to save resources of chromium, technology of flux-cored wire surfacing is of great practical interest. In this case Cr2O3 chromium oxide and carbon as a reducing agent are used as fillers. Thermodynamic assessment of probability of 16 reactions between them under standard conditions and for certain reactions under conditions different from standard was carried out using tabulated thermodynamic data of reactants in temperature range of 1500 – 3500 K. The following states were considered as standard states for reactants: Cr(ref) (reference state, melting point 2130 K, boiling point 2952 K), Cr(liq), Cr(gas), Cr2O3 (cr, liq), Cr2O3 (gas), C(ref), and as possible reaction products and standard states for them CO(gas), CO2 (gas), Cr23C6 (сr), Cr7C3 (cr), Cr3C2 (cr). Probability of reactions was estimated using standard Gibbs energy and the Gibbs energy calculated using the Van Goff isotherm equation. Dissolution of chromium in metal of surfacing bath or probable partial pressures of CO and CO2 in gas phase was taken into account and was calculated from equilibrium of carbon gasification reaction. Presence of carbon in flux-cored wire with chromium oxide Cr2O3 as a reducing agent will necessarily lead to occurrence of reduction reactions with generation of chromium carbides, and possibly chromium itself. Generation of Cr7C3 (сr) carbide is likely. With longer life time of chromium oxide and carbon at a temperature above 2500 K, generation of chromium as a component of the surfacing bath is more thermodynamically probable than generation of its carbides. Chromium oxide has the highest reactivity in Cr2O3 (liq) state. Direct reduction is preferential. Generation of CO(gas) as a product of carbon oxidation is more probable. Dissolution of chromium in metal increases thermodynamic probability of reactions with its generation and further reduces probability of reactions in which chromium is the starting material.

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Prokopowicz, M., P. Konieczka, and J. Namiesnik. "A New Approach to Generation of Standard Gas Mixtures used in the Calibration of Gas Analysers." Environmental Technology 20, no. 10 (October 1999): 1065–73. http://dx.doi.org/10.1080/09593332008616903.

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Aoyagi, Reiji, Yoshika Sekine, Yuichiro Kaifuku, and Kunitoshi Matsunobu. "Development of Continuous Gas Generation Method for Hydrogen Chloride Using Azeotropic Hydrochloric Acid System." ChemEngineering 6, no. 1 (February 1, 2022): 12. http://dx.doi.org/10.3390/chemengineering6010012.

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Standard gases are often prepared using high-pressure gas cylinders. However, it is difficult to accurately prepare a known concentration of hydrogen chloride (HCl) gas using this method because HCl is highly corrosive and adsorptive. In this study, a simple method for the continuous generation of HCl gas was developed using a diffusion tube containing hydrochloric acid and a nitrogen carrier gas. The concentration of HCl produced from this system was almost unstable, but constant gas generation was realized for several hours when azeotropic hydrochloric acid (20.6% HCl in water) and a temperature near the azeotropic point (108.5 °C) were used, resulting in the generation of 103.6 ppm (mean, n = 5) of HCl gas with a relative standard deviation (RSD) of 2.34%. In this case, the percentage of HCl present in the entire gas mixture of HCl and water vapor was 22.5%, which is almost equivalent to the HCl content in the azeotropic hydrochloric acid (20.6%). The HCl concentration could also be controlled by changing the flow rate of the carrier gas. This work demonstrates a simple technique based on the diffusion theory that allows for the constant, controllable generation of a known concentration of HCl gas using an azeotropic hydrochloric acid system.

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Nieto, Rafael, Celina Gonzalez, Ignacio Lopez, and Angel Jimenez. "Efficiency of a standard gas-turbine power generation cycle running on different fuels." International Journal of Exergy 9, no. 1 (2011): 112. http://dx.doi.org/10.1504/ijex.2011.041433.

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Veres, P., J. B. Gilman, J. M. Roberts, W. C. Kuster, C. Warneke, I. R. Burling, and J. de Gouw. "Development and validation of a portable gas phase standard generation and calibration system for volatile organic compounds." Atmospheric Measurement Techniques Discussions 3, no. 1 (January 29, 2010): 333–57. http://dx.doi.org/10.5194/amtd-3-333-2010.

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Abstract. We report on the development of an accurate, portable, dynamic calibration system for volatile organic compounds (VOCs). The Mobile Organic Carbon Calibration System (MOCCS) combines the production of gas-phase VOC standards using permeation or diffusion sources with quantitative total organic carbon (TOC) conversion on a palladium surface to CO2 in the presence of oxygen, and the subsequent CO2 measurement. MOCCS was validated using three different comparisons: (1) TOC of high accuracy methane standards compared well to expected concentrations (3% relative error), (2) a gas-phase benzene standard was generated using a permeation source and measured by TOC and gas chromatography mass spectrometry (GC-MS) with excellent agreement (<4% relative difference), and (3) total carbon measurement of 4 known gas phase mixtures were performed and compared to a calculated carbon content to agreement within the stated uncertainties of the standards. Measurements from laboratory biomass burning experiments of formic acid by negative-ion proton-transfer chemical-ionization mass spectrometry (NI-PT-CIMS) and formaldehyde by proton transfer reaction-mass spectrometry (PTR-MS), both calibrated using MOCCS, were compared to open path Fourier transform infrared spectroscopy (OP-FTIR) to validate the MOCCS calibration and were found to compare well (R2 of 0.91 and 0.99 respectively).

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Veres, P., J. B. Gilman, J. M. Roberts, W. C. Kuster, C. Warneke, I. R. Burling, and J. de Gouw. "Development and validation of a portable gas phase standard generation and calibration system for volatile organic compounds." Atmospheric Measurement Techniques 3, no. 3 (June 16, 2010): 683–91. http://dx.doi.org/10.5194/amt-3-683-2010.

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Abstract. We report on the development of an accurate, portable, dynamic calibration system for volatile organic compounds (VOCs). The Mobile Organic Carbon Calibration System (MOCCS) combines the production of gas-phase VOC standards using permeation or diffusion sources with quantitative total organic carbon (TOC) conversion on a palladium surface to CO2 in the presence of oxygen, and the subsequent CO2 measurement. MOCCS was validated using three different comparisons: (1) TOC of high accuracy methane standards compared well to expected concentrations (3% relative error), (2) a gas-phase benzene standard was generated using a permeation source and measured by TOC and gas chromatography mass spectrometry (GC-MS) with excellent agreement (<4% relative difference), and (3) total carbon measurement of 4 known gas phase mixtures were performed and compared to a calculated carbon content to agreement within the stated uncertainties of the standards. Measurements from laboratory biomass burning experiments of formic acid by negative-ion proton-transfer chemical-ionization mass spectrometry (NI-PT-CIMS) and formaldehyde by proton transfer reaction-mass spectrometry (PTR-MS), both calibrated using MOCCS, were compared to open path Fourier transform infrared spectroscopy (OP-FTIR) to validate the MOCCS calibration and were found to compare well (R2 of 0.91 and 0.99, respectively).

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Grandy, Jonathan J., Khaled Murtada, João Raul Belinato, Paola Alejandra Ortiz Suárez, and Janusz Pawliszyn. "Development and validation of an improved, thin film solid phase microextraction based, standard gas generating vial for the repeatable generation of gaseous standards." Journal of Chromatography A 1632 (November 2020): 461541. http://dx.doi.org/10.1016/j.chroma.2020.461541.

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Gorbacheva, Aleksandra, and Oleg Rodinkov. "Chromate membrane generation of volatile organic compounds standard gas mixtures at the ppm level." Аналитика и контроль 22, no. 1 (2018): 75–82. http://dx.doi.org/10.15826/analitika.2018.22.1.002.

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Yiming, Abilimit, Xiujian Ding, Liangrong Qian, Hailei Liu, Maoguo Hou, and Zhongfa Jiang. "Gas Generation Potential of Permian Oil-Prone Source Rocks and Natural Gas Exploration Potential in the Junggar Basin, NW China." Applied Sciences 12, no. 22 (November 8, 2022): 11327. http://dx.doi.org/10.3390/app122211327.

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The Junggar Basin, where twenty-seven oil fields and five gas fields have been discovered, is a typical “oil basin” with proven ratio of natural gas of 5.3%. The amount of natural gas from Permian source rocks has been found in the western margin of the basin, but no large-scale natural gas reservoir has been discovered. The key to natural gas exploration is whether Permian oil-prone source rocks have large gas generation potential. Based on the comprehensive analysis of geochemical features and hydrocarbon generation simulation experiments, it is proved that the gas generation intensity could meet the standard of medium to large gas-fields (20 × 108 m3/km2) at a depth of more than 6500 m. In the Penyijing and Shawan Sags, the burial depth of the Fengcheng Formation source rocks is between 8500 m and 10,000 m, respectively. It could be concluded that the Permian source rocks in the Penyijingxi and Shawan Sags have relative higher gas generation potential. In addition to high natural gas generation potential, two sets of effective reservoirs (wreathing volcanic rocks and secondary dissolution of sandy conglomerates) and thick caprocks with overpressure are developed in the most areas of Junggar Basin. Recently, natural gas reservoirs have been discovered and industrial natural gas had been obtained around the Penyijingxi Sag, Shawan Sags, and the Southern margin of the Junggar Basin. Our research results and natural gas exploration practice show that the Junggar Basin have relatively large natural gas exploration potential.

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Kvach, I., and S. Kvach. "Interconnection of FSES HE on 21.03.01 “Oil and Gas Business” and Professional Standard “Specialist in Production of Oil, Gas and Gas Condensate” on the Example of Implementation Disciplines." Bulletin of Science and Practice 6, no. 9 (September 15, 2020): 401–7. http://dx.doi.org/10.33619/2414-2948/58/40.

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The article makes an attempt to analyze the situation in the labor market in modern Russian society in connection with new conditions, rapidly changing technologies, digitalization of all production and management processes, and what awaits a university graduate in a new labor reality. The article deals with the issue of conjugation of federal educational standards of higher education of generation 3++ and professional standards in the implementation of bachelor’s programs. The study is based on the example of interfacing FSES HE 21.03.01 “Oil and Gas Business” and the professional standard “Specialist in oil, gas and gas condensate production” in the context of the implementation of disciplines Technological equipment of the oil and gas industry and Maintenance and repair of oilfield equipment and the formation of professional competence: able to carry out work for diagnostics, maintenance, repair and operation of technological equipment in accordance with the chosen field of professional activity at the Yugra State University. The positive aspects of the interface between PS and FSES of HE in the implementation of educational programs of higher education, the difficulties arising on the way of this process and possible solutions are noted.

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Yan, Guanxi, Zhixin Cheng, Ye Ma, Alexander Scheuermann, and Ling Li. "Applying Imaging Technique to Investigate Effects of Solute Concentrations and Gas Injection Rates on Gas Bubble Generation." Geofluids 2022 (October 11, 2022): 1–26. http://dx.doi.org/10.1155/2022/2046267.

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This work investigated the bubble size variation under various aqueous conditions, including saline and surfactant solutions, with different gas injection rates using a commercial bubble analyzer. The results show that salt and surfactant can minimize bubble size with increasing solute concentration, and the surfactant outperforms salt. In addition, the critical coalescence concentrations (CCC) of salt and surfactant could be determined at 20 g/l and 20 mg/l, respectively, over which bubble mean size cannot be further reduced. On the other hand, the gas injection rate, compared to the solute concentration, has minor effects on bubble size variation. Nonetheless, there is a critical coalescence injection rate (CCIR) of 30 ml/min for surfactant solution, over which the standard deviation of the bubble size distribution (BSD) cannot be further increased. In principle, this work improves the accuracy and efficiency of the bubble analyzer. It also presents a sound understanding of two influential factors rather than a single-factor controlling bubble size. Most importantly, it is the first time to observe and propose the concept of CCIR to describe how the gas injection rate influences the standard deviation of BSD. Based on those results and findings, it is able to conclude that bubble size control, whose mechanism has been previously identified as the bubble collision and coalescence rather than the surface tension of water solutions, is actually dominated by not only the solute concentration but also the gas injection rate when a porous air sparger is used to generate bubbles. It is expected that this work could contribute to laboratory modeling bubbly flow in a porous medium in order to bring more insights into the mechanism of soil gas leaking through soil strata.

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Grützke, Martin, Waldemar Weber, Martin Winter, and Sascha Nowak. "Structure determination of organic aging products in lithium-ion battery electrolytes with gas chromatography chemical ionization mass spectrometry (GC-CI-MS)." RSC Advances 6, no. 62 (2016): 57253–60. http://dx.doi.org/10.1039/c6ra09323j.

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For Gas Chromatography Chemical Ionization Mass Spectrometry (GC-CI-MS) method development, a standard lithium-ion battery (LIB) electrolyte was thermally aged at 95 °C for a faster generation of decomposition products.

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Tirtosoekotjo, Soedjoko, and Bambang Suwondo Rahardjo. "RANCANGAN DASAR GASIFIER BATUBARA SIRKULASI UNGGUN MENGAMBANG UNTUK MEMBANGKITKAN LISTRIK 1 MW." Jurnal Energi dan Lingkungan (Enerlink) 7, no. 1 (June 15, 2011): 16. http://dx.doi.org/10.29122/elk.v7i1.2730.

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There are 3 choices in accommodating power station facility which have beeninstalled to fulfill standard regulation of environmental quality which progressivelytighten. Firstly, facility modification of pulverized–coal fired power plant byapplying a flue–gas desulfurisation technology throw away to cost moneyinstallation of tired which can 20% of total cost development of it. Secondly,modification system of coal fired power generation become natural gas combinedcycle (NGCC) can reach low emission, but fuel cost relatively high, so willinfluence the electricity generating cost. Third, modification system of electricgeneration which have been installed by utilizing a mechanism of coalgasification is most efficient and best alternative to yield an environmentalfriendly of electric generation combined cycle. In this paper, writer try to make abasic design of circulating fluidized–bed coal gasifier using clay catalist relatedon third choice which expected applicable in the next future to come replacepower station system which have ended a period as well as newly even if.Kata Kunci: gasifier batubara unggun mengambang, katalis tanah liat,pembangkit listrik

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Susaya, Janice, Ki-Hyun Kim, Jinwoo Cho, and David Parker. "The controlling effect of temperature in the application of permeation tube devices in standard gas generation." Journal of Chromatography A 1225 (February 2012): 8–16. http://dx.doi.org/10.1016/j.chroma.2011.12.066.

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Zhang, Zhiyu, Rongrong Zhai, Xinwei Wang, and Yongping Yang. "Sensitivity Analysis and Optimization of Operating Parameters of an Oxyfuel Combustion Power Generation System Based on Single-Factor and Orthogonal Design Methods." Energies 13, no. 4 (February 23, 2020): 998. http://dx.doi.org/10.3390/en13040998.

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The main purpose of this paper is to quantitatively analyze the sensitivity of operating parameters of the system to the thermodynamic performance of an oxyfuel combustion (OC) power generation system. Therefore, the thermodynamic model of a 600 MW subcritical OC power generation system with semi-dry flue gas recirculation was established. Two energy consumption indexes of the system were selected, process simulation was adopted, and orthogonal design, range analysis, and variance analysis were used for the first time on the basis of single-factor analysis to conduct a comprehensive sensitivity analysis and optimization research on the changes of four operating parameters. The results show that with increasing oxygen purity, the net standard coal consumption rate first decreases and then increases. With decreasing oxygen concentration, the recirculation rate of dry flue gas in boiler flue gas ( χ 1 ) and an increasing excess oxygen coefficient, the net standard coal consumption rate increases. The net electrical efficiency was just the opposite. The sensitivity order of two factors for four indexes is obtained: the excess oxygen coefficient was the main factor that affects the net standard coal consumption rate and the net electrical efficiency. The influence of oxygen concentration and oxygen purity was lower than that of excess oxygen coefficient, and χ 1 has almost no effect.

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., Ohwofadjeke, and Paul Ogheneochuko. "TECHNO-ECONOMIC STUDY OF ELECTRICITY GENERATING POTENTIALS OF FLARED GASES IN KOKORI TOWN OF DELTA STATE, NIGERIA." International Journal of Engineering Applied Sciences and Technology 7, no. 4 (August 1, 2022): 233–38. http://dx.doi.org/10.33564/ijeast.2022.v07i04.037.

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According to the Department of Petroleum resource (DPR) in its 2018 annual report, 11% of total gas production in Nigeria was flared that year, which translate into about 88.06 BSCF (billions standard cubic feet) of gases that could have been delivered to power plants. This work aims to study the economic benefits of utilizing flared gases for power generation in Nigeria using Kokori Island in Delta State as a case study. Data such as flare volumes and gas turbines fuel consumption were obtained from July to December 2018. The research work was carried out using a five steps methodology which include; Intensive literature review, Site visits, Data collection, Data classification and analysis using payback period. Primary data used were collected through direct measurement of related parameters, The following findings were made; (1)That about 86 % ($5, 002, 391.844) of the total annual operating and maintenance cost goes into purchasing of natural gas for fuelling the turbines to generate electricity, (2) That the average daily gas flaring volume is about 7.2 mmscf/d (Million Standard Cubic Feet per Day) which translates into about 2,625 million mmscf per year, (3) Hitachi H25 gas turbine generator requires about 3.5657 mmscf of natural gas per day to generate 22.9 Mega Watts of electricity which translates into about 1,301 mmscf per year. The following are the recommendations;(1) That the federal government through its Department of Petroleum resource (DPR) should enforce a total ban on gas flaring in Nigeria, (2) That the federal government of Nigeria should decentralize electricity generation and distribution to encourage more investors through a competitive market system, (3) That more indigenous engineers and scientists should undertake researches in electricity generation, transmission and distribution so as to make the commodity available and affordable to Nigerian citizens in the nearest future.

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Stoyanov, Stoyan Nedelchev, Veselin Mihaylov, Zdravko Ivanov, and Radostin Radev. "System for studying the parameters of gas solenoid valves." ANNUAL JOURNAL OF TECHNICAL UNIVERSITY OF VARNA, BULGARIA 5, no. 2 (December 30, 2021): 112–21. http://dx.doi.org/10.29114/ajtuv.vol5.iss2.259.

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The aim of the present work is to construct a test stand for determining the characteristics of different fourth generation gas injectors working under various conditions as close as possible to the actual operating ones. For this purpose, the standard fourth generation gas system and liquefied petroleum gas (LPG) as a working fluid were used for the stand. A system has been developed to maintain the gas leakage pressure equal in value to the pressure in the intake manifold of a Spark Ignition (SI) engine. Used LPG is compressed and liquefied for reuse. Additionally, safety measures are taken. The stand provides the right conditions for determining the influence of the nozzle diameter, the length of the connecting pipe between the injector and the intake manifold, the differential pressure upstream and downstream of the injector and other factors that affect these characteristics, which may be different when installing LPG system to an internal combustion engine.

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Stefanizzi, Michele, Tommaso Capurso, Giovanni Filomeno, Marco Torresi, and Giuseppe Pascazio. "Recent Combustion Strategies in Gas Turbines for Propulsion and Power Generation toward a Zero-Emissions Future: Fuels, Burners, and Combustion Techniques." Energies 14, no. 20 (October 15, 2021): 6694. http://dx.doi.org/10.3390/en14206694.

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The effects of climate change and global warming are arising a new awareness on the impact of our daily life. Power generation for transportation and mobility as well as in industry is the main responsible for the greenhouse gas emissions. Indeed, currently, 80% of the energy is still produced by combustion of fossil fuels; thus, great efforts need to be spent to make combustion greener and safer than in the past. For this reason, a review of the most recent gas turbines combustion strategy with a focus on fuels, combustion techniques, and burners is presented here. A new generation of fuels for gas turbines are currently under investigation by the academic community, with a specific concern about production and storage. Among them, biofuels represent a trustworthy and valuable solution in the next decades during the transition to zero carbon fuels (e.g., hydrogen and ammonia). Promising combustion techniques explored in the past, and then abandoned due to their technological complexity, are now receiving renewed attention (e.g., MILD, PVC), thanks to their effectiveness in improving the efficiency and reducing emissions of standard gas turbine cycles. Finally, many advances are illustrated in terms of new burners, developed for both aviation and power generation. This overview points out promising solutions for the next generation combustion and opens the way to a fast transition toward zero emissions power generation.

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Mehrpanahi, Abdollah, Mohammadreza Arbabtafti, and Gholamhassan Payganeh. "Robust controller design for a three-shaft industrial gas turbine in the infinite grid power generation." Transactions of the Institute of Measurement and Control 42, no. 1 (October 21, 2019): 131–56. http://dx.doi.org/10.1177/0142331219876757.

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Due to the sensitivity of gas turbines’ power generation in Iran, robustness is considered as a crucial matter and the controllers play an essential role in this objective. The common controllers used in gas turbines are usually based on standard performance. Whereas, robust controllers demonstrate acceptable performance in the presence of adverse factors such as uncertainties, disturbances, and input step changes. In this study, dynamic structures and various robust control design scenarios for an MGT-30 three-shaft gas turbine have proposed. Input-output matrices have been presented based on the dynamic model structures, and a standard robust controller structure has been used to design and present transfer matrices. Four scenarios have been considered in the robust control design according to the number of control variables, uncertainties, and disturbance effects, evolutionally, respectively. [Formula: see text] and [Formula: see text] methods were used in the controller design when presenting the results of using the existing PID controller. The results show that with the increase and develop in parameters influencing the production of the actual system behavior and the controller responses improve noticeably. Finally, the fourth scenario was proposed as a scenario with more desirable robustness features than other scenarios, which provide a complete array of robust controllers.

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Crego, Aurora, Julio San Roman, and Enrique Conejero Jarque. "Visible short-pulses generation by nonlinear propagation of necklace beams in capillaries." EPJ Web of Conferences 238 (2020): 11005. http://dx.doi.org/10.1051/epjconf/202023811005.

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We study numerically the propagation of necklace beams through a gas-filled capillary. Ultra-short pulses in the visible (VIS) region can be obtained due to the spectral broadening of these necklace beams. This new source of few-cycle VIS pulses can be generated carrying tens of microjoules of energy using these special beams, being a valuable tool for the improvement of the standard post-compression schemes in terms of spatial stability and output energy.

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Alonso, Maria Luz, Ane Espinazo, Rosa Maria Alonso, Jose Ignacio Lombraña, Jesús Izcara, and Josu Izaguirre. "New Generation of SF6-Free Medium-Voltage Switchgear for the Electrical Network: Stability and Toxicity Studies of Trans-1,1,1,4,4,4-Hexafluorobut-2-ene with N2 Gas Mixture." Processes 11, no. 1 (January 3, 2023): 136. http://dx.doi.org/10.3390/pr11010136.

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Binary gas mixture of N2 and trans-1,1,1,4,4,4-hexafluorobut-2-ene (HFO4E) is presented as an alternative to SF6 in medium-voltage electrical equipment. Its stability was tested under different conditions. No change was observed in the gas mixture after a permanent AC voltage of 30 kV applied for two years or during the making operations with a standard load-break switch. The same behavior was obtained under dielectric tests, electrical arcs and temperature rise tests according to the IEC 62271-1:2011 standard. For all of these conditions, the concentration of HFO4E remains practically unchanged; there is no impact on the insulation properties of the system and the degradation products formed would not affect the health and the environment if there were leaks. In these studies, gas mixtures samples were analyzed by a validated methodology based on gas chromatography coupled to mass spectrometry and thermal conductivity detectors. Finally, an OECD TG 403 acute inhalation toxicity test was also carried out with the gas mixture aged after the mentioned making operations. None of the mice used in the toxicity test were affected after 4 h of exposition to an ambient air with 30,000 ppmv of the gas mixture.

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Rosini, Alessandro, Alessandro Palmieri, Damiano Lanzarotto, Renato Procopio, and Andrea Bonfiglio. "A Model Predictive Control Design for Power Generation Heavy-Duty Gas Turbines." Energies 12, no. 11 (June 7, 2019): 2182. http://dx.doi.org/10.3390/en12112182.

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The new electric power generation scenario, characterized by growing variability due to the greater presence of renewable energy sources (RES), requires more restrictive dynamic requirements for conventional power generators. Among traditional power generators, gas turbines (GTs) can regulate the output electric power faster than any other type of plant; therefore, they are of considerable interest in this context. In particular, the dynamic performance of a GT, being a highly nonlinear and complex system, strongly depends on the applied control system. Proportional–integral–derivative (PID) controllers are the current standard for GT control. However, since such controllers have limitations for various reasons, a model predictive control (MPC) was designed in this study to enhance GT performance in terms of dynamic behavior and robustness to model uncertainties. A comparison with traditional PID-based controllers and alternative model-based control approaches (feedback linearization control) found in the literature demonstrated the effectiveness of the proposed approach.

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Marks, Stanislaw, Jacek Dach, Jose Luis Garcia-Morales, and Francisco Jesus Fernandez-Morales. "Bio-Energy Generation from Synthetic Winery Wastewaters." Applied Sciences 10, no. 23 (November 25, 2020): 8360. http://dx.doi.org/10.3390/app10238360.

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In Spain, the winery industry exerts a great influence on the national economy. Proportional to the scale of production, a significant volume of waste is generated, estimated at 2 million tons per year. In this work, a laboratory-scale reactor was used to study the feasibility of the energetic valorization of winery effluents into hydrogen by means of dark fermentation and its subsequent conversion into electrical energy using fuel cells. First, winery wastewater was characterized, identifying and determining the concentration of the main organic substrates contained within it. To achieve this, a synthetic winery effluent was prepared according to the composition of the winery wastewater studied. This effluent was fermented anaerobically at 26 °C and pH = 5.0 to produce hydrogen. The acidogenic fermentation generated a gas effluent composed of CO2 and H2, with the percentage of hydrogen being about 55% and the hydrogen yield being about 1.5 L of hydrogen at standard conditions per liter of wastewater fermented. A gas effluent with the same composition was fed into a fuel cell and the electrical current generated was monitored, obtaining a power generation of 1 W·h L−1 of winery wastewater. These results indicate that it is feasible to transform winery wastewater into electricity by means of acidogenic fermentation and the subsequent oxidation of the bio-hydrogen generated in a fuel cell.

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J. P. Spinhirne and J. A. Koziel. "GENERATION AND CALIBRATION OF STANDARD GAS MIXTURES OR VOLATILE FATTY ACIDS USING PERMEATION TUBES AND SOLID-PHASE MICROEXTRACTION." Transactions of the ASAE 46, no. 6 (2003): 1639–46. http://dx.doi.org/10.13031/2013.15634.

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Chen, Hui Yong, Qiang Zhang, Qin Zhou, and Yong Hui Xie. "Study of a Hybrid Wind and Solar Energy Power System." Applied Mechanics and Materials 316-317 (April 2013): 28–31. http://dx.doi.org/10.4028/www.scientific.net/amm.316-317.28.

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A new kind of hybrid wind and solar energy power system was proposed in this paper. In the hybrid system, the technologies of compressed air energy storage (CAES), solar heat storage and gas-steam combined cycle power generation were combined together. At same oil consumption of 19.48 t/h, the output power of the hybrid system in the paper was 194.69 MW, while that of the conventional gas-steam combined cycle was 103.15 MW. The difference between the two cycles was 91.54 MW, which was equivalent to the amount of wind and solar energy power generation. When annual effective operating time of the hybrid system was 2600 h, the power output of wind and solar energy power generation reached 238 million kW•h. If coal-fired power plants were taken as the reference standard, about 113,050 tons of coal was saved per year. An overall benefit of Ұ604.28~626.01 million was obtained per year. As a result, a good economic, environmental and social benefit was achieved.

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Tsukahara, Yusuke, Osamu Hirayama, Nobuo Takeda, Toru Oizumi, Hideyuki Fukushi, Nagisa Sato, Toshihiro Tsuji, Kazushi Yamanaka, and Shingo Akao. "A Novel Method and an Equipment for Generating the Standard Moisture in Gas Flowing through a Pipe." Sensors 18, no. 10 (October 13, 2018): 3438. http://dx.doi.org/10.3390/s18103438.

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When inert gas containing water molecules flows into a metal pipe, the water molecules cannot exit instantaneously from the outlet of the pipe but are captured at adsorption sites on the inner surface of the pipe until most of the sites are occupied. A theoretical model and a subsequent experiment in this article show that the delay time depends on the amount of moisture level; the higher the moisture-level, the shorter the delay time. Based on the result, we propose a new method and its implementation to the validation of a standard moisture generation to be used in the field measurement such as in factories and pipe lines.

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Neudeck, Philip G., David J. Spry, Andrew J. Trunek, Laura J. Evans, Liang Yu Chen, Gary W. Hunter, and D. Androjna. "Hydrogen Gas Sensors Fabricated on Atomically Flat 4H-SiC Webbed Cantilevers." Materials Science Forum 600-603 (September 2008): 1199–202. http://dx.doi.org/10.4028/www.scientific.net/msf.600-603.1199.

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This paper reports on initial results from the first device tested of a “second generation” Pt-SiC Schottky diode hydrogen gas sensor that: 1) resides on the top of atomically flat 4H-SiC webbed cantilevers, 2) has integrated heater resistor, and 3) is bonded and packaged. With proper selection of heater resistor and sensor diode biases, rapid detection of H2 down to concentrations of 20 ppm was achieved. A stable sensor current gain of 125 ± 11 standard deviation was demonstrated during 250 hours of cyclic test exposures to 0.5% H2 and N2/air.

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Song, Yong Woo, Min Young Kim, Min Hee Chung, Young Kwon Yang, and Jin Chul Park. "NOx-Reduction Performance Test for TiO2 Paint." Molecules 25, no. 18 (September 7, 2020): 4087. http://dx.doi.org/10.3390/molecules25184087.

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In South Korea, the gradual increase in particulate matter generation has received significant attention from central and local governments. Exhaust gas, which contains nitrogen oxides (NOx), is one of the main sources of particulate matter. In this study, the reduction of NOx using a coating material mixed with a titanium dioxide (TiO2) photocatalyst was demonstrated. The NOx reduction performance of the TiO2 photocatalyst-infused coating was evaluated by applying the ISO 22197-1: 2007 standard. Subsequently, the performance was evaluated by changing the NO gas concentration and ultraviolet (UV)-A irradiance under standard experimental conditions. It was determined that NOx reduction can be achieved even if the NO gas concentration and UV-A irradiance are lower than those under the standard conditions when the TiO2 photocatalyst-infused coating was used. This study revealed that NOx reduction can be realized through TiO2 photocatalyst-infused coating in winter or cloudy days with a low solar altitude. It was also confirmed that compared with the UV-A irradiance, the NO gas concentration has a greater effect on the NOx reduction performance of the TiO2 photocatalyst-infused coating. These findings can be used to evaluate a variety of construction materials with TiO2 photocatalysts in the future.

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Kharoua, Nabil, Lyes Khezzar, and Zoubir Nemouchi. "Study of the Pressure Drop and Flow Field in Standard Gas Cyclone Models Using the Granular Model." International Journal of Chemical Engineering 2011 (2011): 1–11. http://dx.doi.org/10.1155/2011/791218.

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A particle-laden flow inside solid gas cyclones has been studied using computational fluid dynamics (CFD). The effects of high temperatures and different particle loadings have been investigated. The Reynolds stress (RSM) model-predicted results, in the case of pure gas, are within engineering accuracy even at high temperatures. Using the granular mixture model for the cases of particle-laden flow, discrepancies occurred at relatively high loadings (up to 0.5 kg/m3). Since the pressure drop is strongly related to the friction inside the cyclone body, the concept of entropy generation has been employed to detect regions of high frictional effects. Friction has been observed to be important at the vortex finder wall, the bottom of the conical-part wall, and the interface separating the outer and the core streams. The discrepancies between the present numerical simulation and the experimental results taken from the existing literature, which are caused by the mixture and turbulence models simplifying assumptions, are discussed in this paper.

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Spitkovsky, Dimitry, Karen Lemke, Tobias Förster, Robert Römer, Stefan Wiedemeier, Jürgen Hescheler, Agapios Sachinidis, and Gunter Gastrock. "Generation of Cardiomyocytes in Pipe-Based Microbioreactor Under Segmented Flow." Cellular Physiology and Biochemistry 38, no. 5 (2016): 1883–96. http://dx.doi.org/10.1159/000445550.

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Background/Aims: Embryonic stem (ES) cells have got a broad range differentiation potential. The differentiation is initiated via aggregation of non-differentiated ES cells into embryoid body (EB) capable of multi-lineage development. However experimental variables present in standard differentiation techniques lead to high EB heterogeneity, affecting development into the cells of desired lineage, and do not support the process automatization and scalability. Methods: Here we present a novel pipe based microbioreactor (PBM) setup based on segmented flow, designed for spatial maintenance of temperature, nutrition supply, gas supply and sterility. Results: We verified PBM feasibility for continuous process generating cardiac cells starting from single ES cell suspension followed by EB formation for up to 10 days. The ES cells used in the study were genetically modified for cardiac-specific EGFP expression allowing optical monitoring of cardiomyocytes while EBs remained within PBM for up to 10 days. Efficiency of cardiac cells formation within PBM was similar compared to a standard hanging drop based protocol. Conclusion: Our findings ensure further development of microfluidic bioreactor technology to enable robust cardiomyocytes production for needs of drug screening, tissue engineering and other applications.

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Chung, Woojin, Sukyoung Jung, and Soonwoong Chang. "The Influence of Waste Composition on Landfill Gas Generation in a Pilot-Scale Lysimeter." Applied Sciences 9, no. 21 (November 2, 2019): 4677. http://dx.doi.org/10.3390/app9214677.

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The Sudokwon landfill site in Korea, is one of the largest landfill sites in the world, and consists of a first landfill site and second landfill site. The second landfill site generates 3–30 times more H2S than that of the first landfill site. However, the cause of the increase in H2S has not been identified. In this study, the main causes of H2S concentration increase were investigated in the second landfill site in the Sudokwon landfill site. We classified wastes at the Sudokwon landfill site into seven types including Construction and demolition (C&D) debris waste. A lysimeter reactor was designed as a similar environment to the Sudokwon landfill site for simulation. In addition, the experiment was conducted under the same conditions. Three components and elements were analyzed to identify the composition of waste in the landfill site. Leachate was analyzed through a chemical oxygen demand and SO42− standard method. For landfill gas, a gas analyzer was used. The trend in the generation of leachate and landfill gas depending on waste composition at the landfill site was observed and the cause of the increase in H2S was examined. As a result, landfilling of C&D debris waste is recommended as a single landfill.

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Hall, Lawrence O., and Petter Lande. "Generation of Fuzzy Rules from Decision Trees." Journal of Advanced Computational Intelligence and Intelligent Informatics 2, no. 4 (August 20, 1998): 128–33. http://dx.doi.org/10.20965/jaciii.1998.p0128.

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The paper introduces two ways to develop fuzzy rules, using decision trees, from data with continuous valued inputs and outputs. A key problem is dealing with continuous outputs. Output classes are created, then a crisp decision tree is created using a set of fuzzy output classes and letting each training example to partially belong to classes. Alternatively, a discrete set of fuzzy outputs classes is created that includes a selected group of overlaps, such as class A.75/class B.25. Training examples are then provided to a standard decision tree learning program, such as C4.5. In both cases, fuzzy rules are extracted from the resulting decision tree. Output classes must be created for a case in which examples belong to discrete but overlapping classes. We discuss tradeoffs of the two approaches to output class creation. An example of system performance uses a discrete set of overlapping classes on the Box-Jenkins gas furnace prediction problem and a function approximation problem. The learned rules provide effective control and function approximation.

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Koksharev, Oleg M., and Andrey V. Gil. "Study of in-furnace gas-dynamic processes with different design of vortex burners." MATEC Web of Conferences 194 (2018): 01027. http://dx.doi.org/10.1051/matecconf/201819401027.

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The paper considers the combustion chamber of the boiler unit designed for burning Ekibastuz coal by vortex burners with opposed wall firing. Since Ekibastuz coal is not highly reactive, and also has a high content of the mineral part, then vortex burners are used for its combustion. The use of standard two-channel burners leads to increased generation of nitrogen oxides, therefore, in this article the combustion processes of burning Ekibastuz coal using multi-channel burners are considered. The studies were carried out using numerical methods.

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Moore, Richard, and Ian Long. "A low-cost deepwater gas development solution using subsea dehydration." APPEA Journal 56, no. 2 (2016): 604. http://dx.doi.org/10.1071/aj15110.

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Existing solutions for deepwater gas are being challenged in the present economic environment. Surface solutions result in large facilities that are heavy and costly to build. Additionally, subsea solutions are also challenged when confronted with long distance tie-backs. A new approach has emerged—a hybrid sales gas subsea process using subsea dehydration. Existing subsea gas developments rely on either adding chemicals or heat and insulation to avoid hydrate formation. This has been very successful across short to medium tie-back distances and relatively shallow waters. Across longer distances and deeper waters, however, it can prove far less efficient and more costly—this is not the standard method to process gas either onshore or on platforms. The main way to avoid hydrates is to remove the water. Gas dehydration is a standard process operation in surface facilities. This technology now exists in the subsea environment. Active cooling is used to remove the bulk of the water above the hydrate formation temperature. A Sales Gas Subsea process is then used to produce a dry single-phase gas. Power generation and condensate export (if needed) is provided by a simple low-pressure floating production storage and offloading (FPSO) or equivalent surface facility. This process, together with an innovative hybrid development concept, is described in this extended abstract. For many gas fields, this concept can deliver a 20–40% cost reduction at an acceptable project risk.

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Zhang, Zhi Gang. "Study on an Analytical Solution of Gas Seepage Equation Considering the Adsorption Effect." Applied Mechanics and Materials 744-746 (March 2015): 1654–61. http://dx.doi.org/10.4028/www.scientific.net/amm.744-746.1654.

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The functional relationship between rock and coal permeability and gas adsorption quantity has been determined, based on earlier experimental results. Then, by method of mathematical physics, the authors derived an analytical solution for a gas seepage equation in which the adsorption effect has been considered. This analytical solution could be used for developing the theory of Seepage Mechanics and Computational Fluid Dynamics, and for checking and correcting various numerical solutions as a standard solution, and for inspiring various calculating techniques such as difference schemes, grid generation, and others as well. The analytical solution derived in this paper has extremely important practical significance in conducting the arrangement of gas extraction operation in coal mine and the CBM (coal bed methane) development planning.

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Hitchen, Peter, Robert Hutton, and Christopher Tye. "The applications of a commercial gas/liquid separator coupled with an inductively coupled plasma mass spectrometer." Journal of Automatic Chemistry 14, no. 1 (1992): 17–23. http://dx.doi.org/10.1155/s146392469200004x.

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A commercially available hydride generator, with a novel membrane gas-liquid separator, has been coupled to a new ICPMS instrument which itself features many unique design considerations. Little or no optimization of the mass spectrometer or ionization source was required to obtain excellent analytical data; and a variety of matrices have been analysed.The elements As and Se are usually used to demonstrate the effectiveness of a hydride generation system, and these are of particular importance, bearing in mind potential Ar molecular overlaps with isotopes of interest. The flexibility of the hydride generation ICP-MS system is highlighted, with the inclusion of analytical figures of merit for the elements Sn, Sb, Ge and Hg, as well as As and Se. Data obtained by ‘standard’ pneumatic nebulization on the ICP-MS is compared with that obtained with the hydride generator for all of the elements.Improvements of between 50 and 100 times were gained in measurements of three sigma detection limits for all elements in the determinations, including Hg. Measurements were made on several isotopes for particular elements, and the data is included for the purposes of comparison. Stabilities of between 1 and 2.5% were obtained for 0.5 ppb solutions over 10 min measurement periods, all data is presented without using an internal standard.Finally, analytical data from seawater standards, spiked with low levels of As and Se and calibrated against aqueous standards, demonstrate excellent recoveries. This is of particular interest bearing in mind the well-documented molecular interferences from high chloride matrices on As and Se analysis.

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Birchall, Jonathan R., Md Raduanul H. Chowdhury, Panayiotis Nikolaou, Yuri A. Chekmenev, Anton Shcherbakov, Michael J. Barlow, Boyd M. Goodson, and Eduard Y. Chekmenev. "Pilot Quality-Assurance Study of a Third-Generation Batch-Mode Clinical-Scale Automated Xenon-129 Hyperpolarizer." Molecules 27, no. 4 (February 16, 2022): 1327. http://dx.doi.org/10.3390/molecules27041327.

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We present a pilot quality assurance (QA) study of a clinical-scale, automated, third-generation (GEN-3) 129Xe hyperpolarizer employing batch-mode spin-exchange optical pumping (SEOP) with high-Xe densities (50% natural abundance Xe and 50% N2 in ~2.6 atm total pressure sourced from Nova Gas Technologies) and rapid temperature ramping enabled by an aluminum heating jacket surrounding the 0.5 L SEOP cell. 129Xe hyperpolarization was performed over the course of 700 gas loading cycles of the SEOP cell, simulating long-term hyperpolarized contrast agent production in a clinical lung imaging setting. High levels of 129Xe polarization (avg. %PXe = 51.0% with standard deviation σPXe = 3.0%) were recorded with fast 129Xe polarization build-up time constants (avg. Tb = 25.1 min with standard deviation σTb = 3.1 min) across the first 500 SEOP cell refills, using moderate temperatures of 75 °C. These results demonstrate a more than 2-fold increase in build-up rate relative to previously demonstrated results in a comparable QA study on a second-generation (GEN-2) 129Xe hyperpolarizer device, with only a minor reduction in maximum achievable %PXe and with greater consistency over a larger number of SEOP cell refill processes at a similar polarization lifetime duration (avg. T1 = 82.4 min, standard deviation σT1 = 10.8 min). Additionally, the effects of varying SEOP jacket temperatures, distribution of Rb metal, and preparation and operation of the fluid path are quantified in the context of device installation, performance optimization and maintenance to consistently produce high 129Xe polarization values, build-up rates (Tb as low as 6 min) and lifetimes over the course of a typical high-throughput 129Xe polarization SEOP cell life cycle. The results presented further demonstrate the significant potential for hyperpolarized 129Xe contrast agent in imaging and bio-sensing applications on a clinical scale.

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Banihabib, Reyhaneh, and Mohsen Assadi. "A Hydrogen-Fueled Micro Gas Turbine Unit for Carbon-Free Heat and Power Generation." Sustainability 14, no. 20 (October 16, 2022): 13305. http://dx.doi.org/10.3390/su142013305.

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The energy transition with transformation into predominantly renewable sources requires technology development to secure power production at all times, despite the intermittent nature of the renewables. Micro gas turbines (MGTs) are small heat and power generation units with fast startup and load-following capability and are thereby suitable backup for the future’s decentralized power generation systems. Due to MGTs’ fuel flexibility, a range of fuels from high-heat to low-heat content could be utilized, with different greenhouse gas generation. Developing micro gas turbines that can operate with carbon-free fuels will guarantee carbon-free power production with zero CO2 emission and will contribute to the alleviation of the global warming problem. In this paper, the redevelopment of a standard 100-kW micro gas turbine to run with methane/hydrogen blended fuel is presented. Enabling micro gas turbines to run with hydrogen blended fuels has been pursued by researchers for decades. The first micro gas turbine running with pure hydrogen was developed in Stavanger, Norway, and launched in May 2022. This was achieved through a collaboration between the University of Stavanger (UiS) and the German Aerospace Centre (DLR). This paper provides an overview of the project and reports the experimental results from the engine operating with methane/hydrogen blended fuel, with various hydrogen content up to 100%. During the development process, the MGT’s original combustor was replaced with an innovative design to deal with the challenges of burning hydrogen. The fuel train was replaced with a mixing unit, new fuel valves, and an additional controller that enables the required energy input to maintain the maximum power output, independent of the fuel blend specification. This paper presents the test rig setup and the preliminary results of the test campaign, which verifies the capability of the MGT unit to support intermittent renewable generation with minimum greenhouse gas production. Results from the MGT operating with blended methane/hydrogen fuel are provided in the paper. The hydrogen content varied from 50% to 100% (volume-based) and power outputs between 35kW to 100kW were tested. The modifications of the engine, mainly the new combustor, fuel train, valve settings, and controller, resulted in a stable operation of the MGT with NOx emissions below the allowed limits. Running the engine with pure hydrogen at full load has resulted in less than 25 ppm of NOx emissions, with zero carbon-based greenhouse gas production.

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Chen, Q., M. G. G. Gerritsen, and A. R. R. Kovscek. "Modeling Foam Displacement with the Local-Equilibrium Approximation: Theory and Experimental Verification." SPE Journal 15, no. 01 (March 2, 2010): 171–83. http://dx.doi.org/10.2118/116735-pa.

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Summary The gas-mobility-control aspects of foamed gas make it highly applicable for improved oil recovery. Gas-bubble size, often referred to as foam texture, determines gas-flow behavior in porous media. A population-balance model has been developed previously for modeling foam texture and flow in porous media. The model incorporates pore-level mechanisms of foam-bubble generation, coalescence, and transport. Here, we propose a simplified foam model to reduce computational costs. The formulation is based on the assumption of local equilibrium of foam generation and coalescence and is applicable to high- and low-quality foams. The proposed foam model is compatible with a standard reservoir simulator. It provides a potentially useful, efficient tool to predict foam flows accurately at the field scale for designing and managing foamed-gas applications. There are three main contributions of this paper. First, foam-displacement experiments in a linear sandstone core are conducted. A visualization cell is employed to measure the effluent foam-bubble sizes for a transient flow as well as to estimate the in-situ foam-bubble sizes along the length of the core during steady-state flow. These appear to be the first measurements of foam-bubble texture in the entrance region of a core. Additionally, the evolution of aqueous-phase saturation is monitored using X-ray computed tomography (CT), and the pressure profile is measured by a series of pressure taps. Second, the population-balance representation of foam generation by gas-bubble snap-off is modified to extend the capability of the population-balance approach to predict foam-flow behaviors in both the so-called high-quality and low-quality regimes. Third, a simplified population-balance model is developed and implemented with the local-equilibrium approximation. Good agreement is found between the experimental results and the predictions of the simplified model, with a minor mismatch in the entrance region.

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Li, Chaoyue, Shiyu Feng, Lei Shao, Jun Pan, and Weihua Liu. "Experimental study of the solubility and diffusivity of CO2 and O2 in RP-3 jet fuel." Aircraft Engineering and Aerospace Technology 91, no. 2 (February 4, 2019): 216–24. http://dx.doi.org/10.1108/aeat-05-2017-0133.

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Purpose This study aims to get the essential data of the solubility and diffusion coefficient of gas in jet fuel for appropriately designing a kind of on-board inert gas generation system. Design/methodology/approach A test apparatus based on pressure–decay method was constructed to measure solubility and diffusion coefficient of gas in liquid. The test apparatus and method were verified via measurement of solubility and diffusion of CO2 in the pure water. Findings The solubility of CO2 and O2 in RP-3 jet fuel with the temperature from 253 to 313 K under three various pressures were measured and compared with theoretical value calculated by a relative density method provided in the standard of ASTM D2780-92, and the deviation is within 10 per cent. The diffusion coefficients of CO2 and O2 in RP-3 jet fuel are determined by monitoring the gas pressure in a hermetic cell versus time with the temperature from 253 to 333 K. The measured diffusivity-temperature relation can be well fitted through the Arrhenius equation for engineering applications. The obtained correlation can be used to predict the diffusion coefficient of CO2 and O2 in RP-3 jet fuel under a wide temperature range. Practical implications The semi-empirical correlation of solubility and diffusion coefficient in RP-3 jet fuel obtained from the experimental data could be used to support the design of an inert gas generation system. Originality/value There are no essential data of solubility and diffusion of CO2 and O2 in RP-3 jet fuel; therefore, it is fatal if the quantity and rate of mass transfer of CO2 and O2 in RP-3 jet fuel must be assessed, e.g. during the design of green on-board inert gas generation system.

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Galbán, Javier, Jesus Vela, Maria T. Martínez Soria, Maria Aured, and Juan R. Castillo. "Simultaneous Determination of Arsenic(III) and Antimony(III) by Ozone-Induced Gas-Phase Chemiluminescence." Applied Spectroscopy 49, no. 6 (June 1995): 785–90. http://dx.doi.org/10.1366/0003702953964543.

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A combined hydride-generation/gas-phase chemiluminescence (HG-GPCL) method for the determination of arsenic(III) and antimony(III) by using a conventional luminometer is proposed. The method was optimized in terms of the type of reaction chamber, the instrumental settings, and the hydride generation and reaction conditions used. It provides a linear response to As(III) and Sb(III) above a concentration of 0.05 and 0.50 mg L−1, respectively, with a relative standard deviation of ∼3% for both species. Arsenic and antimony can thus be determined simultaneously by (1) their differential effect on the signal obtained with an optical filter placed between the reaction chamber and detector, or (2) the difference between the peak height/peak area ratio of the transient signal for their hydrides. Both procedures were applied to the determination of arsenic and antimony in various synthetic aqueous samples with good accuracy and precision. The effect of potential interferences including anionic and hydride-forming inorganic species was investigated.

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Galaz, Gaspar, Paulo Cortes, Leonardo Bronfman, and Monica Rubio. "12CO(J=3→2) detections in bulges of low surface brightness galaxies with APEX." Proceedings of the International Astronomical Union 3, S245 (July 2007): 191–92. http://dx.doi.org/10.1017/s1743921308017626.

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AbstractUsing the APEX sub-millimeter telescope we have detected for the first time the CO rotational transition 12CO(J=3→2) in two of five low surface brightness galaxies. For galaxies with positive detection, the emission is detected in their bulges, with measured gas velocity dispersion of about 80 km/s and observed main-beam brightness temperature TM B ~ 10 mK. Using a standard CO to H2 conversion factor, we are able to estimate molecular gas masses for LSBs with positive detections, and upper limits for those LSBs with negative detections. Assuming a higher gas temperature for the generation of the 12CO(J=3→2) line compared to that for the 12CO(J=1→0) one, results suggest that a warm molecular gas component is present in bulges, indicating a radiation field preventing the formation of large cooler amounts of molecular gas, compared to high surface brightness galaxies with higher metallicity and likely more dust.

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Taylor, Dennis, Aleksai E. Kontorovich, Andrei I. Larichev, and Miryam Glikson. "PETROLEUM SOURCE ROCKS IN THE ROPER GROUP OF THE MCARTHUR BASIN: SOURCE CHARACTERISATION AND MATURITY DETERMINATIONS USING PHYSICAL AND CHEMICAL METHODS." APPEA Journal 34, no. 1 (1994): 279. http://dx.doi.org/10.1071/aj93026.

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Organic rich shale units ranging up to 350 m in thickness with total organic carbon (TOC) values generally between one and ten per cent are present at several stratigraphic levels in the upper part of the Carpentarian Roper Group. Considerable variation in depositional environment is suggested by large differences in carbon:sulphur ratios and trace metal contents at different stratigraphic levels, but all of the preserved organic matter appears to be algal-sourced and hydrogen-rich. Conventional Rock-Eval pyrolysis indicates that a type I-II kerogen is present throughout.The elemental chemistry of this kerogen, shows a unique chemical evolution pathway on the ternary C:H:ONS diagram which differs from standard pathways followed by younger kerogens, suggesting that the maturation histories of Proterozoic basins may differ significantly from those of younger oil and gas producing basins. Extractable organic matter (EOM) from Roper Group source rocks shows a chemical evolution from polar rich to saturate rich with increasing maturity. Alginite reflectance increases in stepwise fashion through the zone of oil and gas generation, and then increases rapidly at higher levels of maturation. The increase in alginite reflectance with depth or proximity to sill contacts is lognormal.The area explored by Pacific Oil and Gas includes a northern area where the Velkerri Formation is within the zone of peak oil generation and the Kyalla Member is immature, and a southern area, the Beetaloo sub-basin, where the zone of peak oil generation is within the Kyalla Member. Most oil generation within the basin followed significant folding and faulting of the Roper Group.

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Patel, Manish, and H. Raheman. "An Approach for Power Generation with Reduced Fuel Consumption using PTO Driven Generator." Current World Environment 11, no. 2 (August 25, 2016): 544–53. http://dx.doi.org/10.12944/cwe.11.2.24.

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Using the gear up throttle down concept, suitable power take off (PTO) speed required to run a PTO powered generator was decided. For this PTO test was carried out using an eddy current dynamometer. The tractor engine was loaded to different torque values at different engine speeds for obtaining constant PTO power corresponding to the full load of the generator. Fuel consumption, smoke level, exhaust gas temperature and coolant temperature were measured during PTO test. Engine speed fluctuation and engine overloading were also observed to judge whether the engine was running smoothly, or it was overloaded. The specific fuel consumption was reduced from 268.9 g/kW h at 1579 rpm to 242.9 g/kW h at 1000 rpm. Considering the engine speed fluctuation, overloading of the engine, rapid rise of smoke level, exhaust gas temperature and coolant temperature, an engine speed of 1215 rpm was recommended instead of 1579 rpm (corresponding to standard PTO speed of 540 rpm). A suitable power transmission system comprising belt and pulley drive was designed to run the generator at rated speed of 1500 rpm. When the generator was operated at reduced PTO speed of 415 rpm (corresponding to engine speed of 1215 rpm) in comparison to standard PTO speed of 540 rpm, fuel saving of 0.35 l/h to 0.55 l/h and 0.43 l/h to 0.48 l/h was achieved at different alternating current (AC) and direct current (DC) loads on the generator, respectively. Following this approach, a considerable amount of fuel energy could be saved while generating electric power using tractor. Efficient use of fuel will reduce the overall production cost of agricultural products as well as help in protecting our environment.

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Okabe, Shigemitsu, Sadayuki Yuasa, and Shuhei Kaneko. "Evaluation of breakdown characteristics of gas insulated switchgears for non-standard lightning impulse waveforms - analysis and generation circuit of non-standard lightning impulse waveforms in actual field." IEEE Transactions on Dielectrics and Electrical Insulation 14, no. 2 (April 2007): 312–20. http://dx.doi.org/10.1109/tdei.2007.344609.

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Testa, Bridget Mintz. "Wind in a Bottle." Mechanical Engineering 130, no. 05 (May 1, 2008): 22–25. http://dx.doi.org/10.1115/1.2008-may-1.

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This article highlights that like everything else wind power is biggest in Texas. But plans to erect thousands of large turbines have utilities scrambling to build a new energy infrastructure. To take advantage of its wind potential, address the state’s fuel diversity problem, and demonstrate sensitivity to regional environmental issues, the 1999 Texas legislature established a “renewable portfolio standard.” This standard sets a goal of 2000 MW of new renewable electricity generation by 2009. Compressed air energy storage (CAES) uses off-peak electricity from the grid to compress air that is stored at high pressures in natural underground repositories. When needed, the compressed air is raised to the surface, expanded in two phases, and then mixed with natural gas. The combination is ignited, turning a gas turbine and producing electricity. Naturally arched salt domes of the type used in the Huntorf and McIntosh plants are not common in West Texas, so the Shell-Luminant CAES plant will use salt beds instead.

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Mulyavin, S. F., E. A. Mulyavina, A. V. Strekalov, Zh M. Kolev, A. I. Filippov, G. Steshenko, and O. A. Bazhenova. "COGNITIVE TECHNOLOGIES IN TEACHING OF BACHELORS AND MASTERS ON DIRECTION «OIL AND GAS BUSINESS»." Oil and Gas Studies, no. 5 (October 30, 2018): 134–41. http://dx.doi.org/10.31660/0445-0108-2018-5-134-141.

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The article describes the experience of usage cognitive technologies in the process of implementing the Federal State Educational Standard of the Third Generation. This experience is based on the development and application in the educational cognitive information system as a kind of program for computers. It contains the algorithms and techniques, which are used in the production when creating project documents for oil and gas fields in Russia. This computer program is part of the electronic educational environment of the university and can be used both for educational purposes, for forming professional competencies of students and in the actual production.

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Widiyanto, Anugerah, Seizo Kato, Naoki Maruyama, and Yoshimasa Kojima. "Environmental Impact of Fossil Fuel Fired Co-Generation Plants Using a Numerically Standardized LCA Scheme." Journal of Energy Resources Technology 125, no. 1 (March 1, 2003): 9–16. http://dx.doi.org/10.1115/1.1510521.

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This paper describes the LCA environmental impacts resulting from fuel fired co-generation systems using our NETS (Numerical Eco-load Total Standard, [1]) scheme having GUI (Graphic User Interface). Following a brief introduction of the NETS evaluation method, firstly the total eco-load from commercial electricity power plants in Japan is numerically calculated in the NETS unit. We take here almost all factors into account including fuel mining, transportation and processing, plant manufacturing, assembling and its building construction, fuel consumption and maintenance during twenty durable years, plant dismantling and waste processing, thermal efficiency and delivery loss, etc. This evaluation greatly helps in the eco-load estimation of co-generation plants when electricity purchase is needed during the plant operation with a minimum eco-load. Next, co-generation systems are paid attention to their ecological effectiveness. Here, we select different fuel fired co-generation plants of natural gas, heavy oil, and coal. Environmental impacts resulting from the respective plants include fossil fuel depletion and natural resources depletion, global warming due to green house gases, ozone layer depletion due to CFC type gas emission, various water and air pollution, rain acidification due to NOx and SOx, waste processing, recycling etc. Each item can be successfully calculated from the inventory database accumulated by authors. Hourly energy demands of electricity and heat (steam, hot water and cold water) are set to a typical model for eight office buildings and two hotels. The NETS method is applied to the co-generation model, resulting in the best cost-operating scheme of co-generation plants with a minimum environmental impact.

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Journal articles on the topic 'Gas standard generation'

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