The field of steelmaking has seen an increased demand in reducing and controlling the amounts of dissolved gases in steel. Hydrogen and nitrogen are two of the most important gases which, when dissolved in liquid steel, affect its properties significantly. Both of these gases can enter the liquid steel either through steelmaking additions or by reaction of the liquid metal with the atmospheric elements. At United States Steel Corporation (U. S. Steel), empirical evidence has shown that hydrated scrap, lime and coke additions are major contributors to hydrogen pickup in liquid steel. Similarly, nitrogen impurities in ferroalloys, coke and scrap are identified sources of nitrogen. In addition, the presence of measurable traces of nitrogen in oxygen gas used at the BOP and Q-BOP has also resulted in elevated levels of nitrogen pickup. There is also an increased likelihood of higher hydrogen and nitrogen in liquid steel from overblow and reblow situations. This additional pickup of hydrogen and nitrogen gases in steel will not only affect the properties of steel; there is also significant potential for hydrogen-induced sticker breakouts to occur at the continuous caster, which could result in significant maintenance costs and productivity losses. Therefore, it is imperative to accurately quantify the amounts of hydrogen and nitrogen in liquid steel. Online hydrogen measurement uses measured hydrogen partial pressure in collaboration with equilibrium constants and interaction coefficients relevant for the hydrogen dissolution reaction. To ensure accurate hydrogen readings from the instrument, those thermodynamic values were reviewed, considering the changes in chemistry and temperature in the steelmaking processes. Similarly, precautions dealing with sample preparation to ensure accurate and reproducible nitrogen measurements using optical spectrometric techniques are identified. Discussions on the potential hydrogen-induced breakouts, when uncontrolled and significantly high levels of hydrogen are present in the liquid steel, are also provided in this paper.
Research Article| October 10, 2017 Late Cretaceous–Cenozoic basin evolution and topographic growth of the Hoh Xil Basin, central Tibetan Plateau Lin Li; Lin Li 1Department of Earth and Environmental Sciences, University of Rochester, Rochester, New York 14627, USA Search for other works by this author on: GSW Google Scholar Carmala N. Garzione; Carmala N. Garzione 1Department of Earth and Environmental Sciences, University of Rochester, Rochester, New York 14627, USA Search for other works by this author on: GSW Google Scholar Alex Pullen; Alex Pullen 1Department of Earth and Environmental Sciences, University of Rochester, Rochester, New York 14627, USA2Department of Geosciences, University of Arizona, Tucson, Arizona 85721, USA Search for other works by this author on: GSW Google Scholar Peng Zhang; Peng Zhang 3Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, China Search for other works by this author on: GSW Google Scholar Yun Li Yun Li 3Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, China Search for other works by this author on: GSW Google Scholar GSA Bulletin (2018) 130 (3-4): 499–521. https://doi.org/10.1130/B31769.1 Article history received: 10 Feb 2017 rev-recd: 26 Jun 2017 accepted: 22 Aug 2017 first online: 10 Oct 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Tools Icon Tools Get Permissions Search Site Citation Lin Li, Carmala N. Garzione, Alex Pullen, Peng Zhang, Yun Li; Late Cretaceous–Cenozoic basin evolution and topographic growth of the Hoh Xil Basin, central Tibetan Plateau. GSA Bulletin 2017;; 130 (3-4): 499–521. doi: https://doi.org/10.1130/B31769.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search nav search search input Search input auto suggest search filter All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract The Hoh Xil Basin in the central Tibetan Plateau was the locus of thick accumulation of terrestrial sediments from the Late Cretaceous to Neogene, providing an archive of regional tectonic activity both before and after initiation of the early Paleogene India-Asia collision. This work focuses on the stratigraphy and provenance of the poorly studied western part of the Hoh Xil Basin. Lithostratigraphy, carbonate oxygen isotopic composition, and deformation features suggest that the braided river and alluvial-fan that dominated the Kangtuo Formation in the southern West Hoh Xil subbasin can be correlated with the Late Cretaceous–early Eocene Fenghuoshan Group deposits of the East Hoh Xil subbasin, whereas deltaic, shallow lacustrine, and evaporite strata of the Suonahu Formation in the central-northern West Hoh Xil subbasin can be correlated to the middle Eocene–early Oligocene Yaxicuo Formation of the East Hoh Xil subbasin. These observations suggest that the eastern and western parts of Hoh Xil Basin evolved as a unified basin during Late Cretaceous–Oligocene time. Detrital zircon U-Pb ages indicate that the Kangtuo Formation and Fenghuoshan Group mainly received detritus from the Qiangtang terrane to the south, whereas the age probability distributions of the Suonahu Formation and Yaxicuo Formation sandstones are more similar to zircon ages reported for the northern Qiangtang terrane and within the Hoh Xil terrane. We favor a tectonic model with Late Cretaceous–early Eocene contractional deformation and topographic growth of the south-central Qiangtang terrane that caused flexural subsidence of the south-central Hoh Xil region within a retroarc foreland basin, relative to the Tanggula thrusts in central Qiangtang. Following the onset of India-Asia collision, the locus of contractional deformation moved northward, marked by activity of the Fenghuoshan and Hoh Xil thrust systems within the Hoh Xil region, and resulting in transformation of the Hoh Xil foreland basin to a hinterland basin. We suggest that both middle Eocene to late Oligocene upper-crustal shortening and associated thickening of the lower crust and mantle lithosphere as well as late Oligocene to Miocene loss of dense mantle lithosphere contributed to the topographic growth of the Hoh Xil Basin. You do not currently have access to this article.
Investigating the adsorption and diffusion processes of shale gas within the nanopores of kerogen is essential for comprehending the presence of shale gas in organic matter of shale. In this study, an organic nanoporous structure was constructed based on the unit structure of Longmaxi shale kerogen. Grand canonical Monte Carlo and molecular dynamics simulation methods were employed to explore the adsorption and diffusion mechanisms of pure CH4, CO2, and N2, as well as their binary mixtures with varying mole fractions. The results revealed that the physical adsorption characteristics of CH4, CO2, and N2 gases on kerogen adhered to the Langmuir adsorption law. The quantity of adsorbed gas molecules increased with rising pressure but decreased with increasing temperature. The variation in the heat of adsorption was also analyzed. Under identical temperature and pressure conditions, the adsorption of CH4 increased with higher mole fractions of CH4, whereas it decreased with greater mole fractions of CO2 and N2. Notably, CO2 molecules exhibited a robust interaction with kerogen molecules compared to the adsorption properties of CH4 and N2. Furthermore, the self-diffusion coefficient of gas within kerogen nanopores gradually decreased with increasing pressure or decreasing temperature. The diffusion capacity of gas molecules followed the descending order N2 > CH4 > CO2 under the same pressure and temperature conditions.
Abstract Mesoporous bimetallic Fe/Co was prepared as a Fenton-like catalyst to degrade the tetracycline hydrochlorides (TC). The nanocasting strategy with KIT-6 as a hard template was carried out to synthesize the mesoporous bimetallic catalyst. The mesoporous bimetallic Fe/Co catalyst was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), nitrogen adsorption-desorption isotherms, and Brunauer-Emmett-Teller (BET) method. The results showed that the catalyst has significant nanofeatures; the surface area, pore size, and particle size were 113.8 m 2 g −1 , 4 nm, and 10 nm, respectively. In addition, the effects of the operating parameters, such as the iron-to-cobalt ratio, pH, H 2 O 2 , and initial TC concentrations on its catalytic performance were investigated. The best operating parameters were as follows: iron-to-cobalt ratio = 2:1 to 1:1, pH = 5–9, H 2 O 2 : 30 mmol, initial TC less than 30 mg/L. Furthermore, the mesoporous bimetallic Fe/Co showed a good performance for degrading TC, achieving a removal rate of 86% of TC after 3 h under the reaction conditions of H 2 O 2 = 30 mmol, mesoporous bimetallic Fe/Co = 0.6 g/L, TC = 30 mg/L, pH = 7.0, and temperature = 25.5 °C. The mesoporous bimetallic Fe/Co catalyst shows good stability and reusability. This work demonstrated that mesoporous bimetallic Fe/Co has excellent catalytic efficiency, smaller amounts of leached ions, and wider pH range, which enhance its potential applications.
A column experiment was conducted to investigate the release of colloids in water-saturated porous media, and the mechanism for the permeability of the water-bearing media changed by release of colloids are discussed. The research results showed that the accumulative amount of colloid particles release in effluent from water-bearing media increased with increasing pH. The accumulative amount of colloid particles in effluent with pore volumes showed a curve of "S" type. Colloid release was restrained under strong acidic condition, while was favorable under the neutral and alkaline conditions, and the critical pH of colloid release was 7. The release of colloids had great influence on the permeability of the water-bearing media, and the permeability of water-bearing media decreased by 98.2 % in the process of the experiment. The migration and interception of the released colloids resulted in the permeability loss of the porous media.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
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