RESUMEN
China is the most important steel producer in the world, and its steel industry is one of the most carbon-intensive industries in China. Consequently, research on carbon emissions from the steel industry is crucial for China to achieve carbon neutrality and meet its sustainable global development goals. We constructed a carbon dioxide (CO2) emission model for China's iron and steel industry from a life cycle perspective, conducted an empirical analysis based on data from 2019, and calculated the CO2 emissions of the industry throughout its life cycle. Key emission reduction factors were identified using sensitivity analysis. The results demonstrated that the CO2 emission intensity of the steel industry was 2.33 ton CO2/ton, and the production and manufacturing stages were the main sources of CO2 emissions, accounting for 89.84% of the total steel life-cycle emissions. Notably, fossil fuel combustion had the highest sensitivity to steel CO2 emissions, with a sensitivity coefficient of 0.68, reducing the amount of fossil fuel combustion by 20% and carbon emissions by 13.60%. The sensitivities of power structure optimization and scrap consumption were similar, while that of the transportation structure adjustment was the lowest, with a sensitivity coefficient of less than 0.1. Given the current strategic goals of peak carbon and carbon neutrality, it is in the best interest of the Chinese government to actively promote energy-saving and low-carbon technologies, increase the ratio of scrap steel to steelmaking, and build a new power system.
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Dióxido de Carbono , Huella de Carbono , Acero , China , Dióxido de Carbono/análisis , Contaminantes Atmosféricos/análisis , Metalurgia , Monitoreo del Ambiente , Industrias , Contaminación del Aire/estadística & datos numéricos , Contaminación del Aire/prevención & controlRESUMEN
The mechanical performance of curved bridges under the action of an earthquake is complex. To obtain the influence of seismic parameters on the seismic response of curved girder bridges, this paper relies on a large slope small-radius curved steel box girder bridge (LSCGB) and selects seismic wave incidence angle, vertical component of ground motion, and site category as seismic parameters to carry out nonlinear time history analysis. Based on the analysis results of the case bridge, it is shown that the torsional vibration of the first 10 modes of LSCGB is significant, the modes are dispersed, and the contribution of high-order modes of vibration cannot be ignored. The most unfavorable seismic wave incidence angle is in the direction of 45°â¼60° counterclockwise Angle from the central connection line of Pier No. 1 and Pier No. 4 of the bridge. The seismic response of the curved bridge components increases with the vertical seismic intensity, and the influence on displacement responses is more significant. The basic vibration period of curved girder bridges built on soft soil sites is extended by approximately 18.23%, and the seismic response of key components increases with the softening of the site soil. Therefore, when analyzing the seismic response of LSCGBs, the influence of vertical component of ground motion and site category should not be ignored.
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Terremotos , Vibración , Movimiento (Física) , Modelos Teóricos , AceroRESUMEN
The corrosion behavior of carbon steel under the coexistence of carbon dioxide and SRB was studied by means of corrosion weight loss, SEM, EDS, in situ pH test, and other methods. The results showed that Chloride ions, temperature, pH, and oxygen coexist with iron bacteria will affect the corrosion under the coexistence of CO2 and SRB, and SRB tends to grow in a favorable environment for itself, and the corrosion rate of X52N at 42 days is slightly higher than that at 21 days. However, the pitting depth increased sharply from 21.20 µm in 21 days to 39.79 µm in 42 days. So that the corrosion can be divided into two stages. First, SRB catalyze the dissolution of FeCO3, leading to local uniform corrosion. Second, SRB directly obtain electrons from the metal surface, resulting in local pitting. In addition, the environment under the stable mineralized biofilm was found to be slightly alkaline.
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Dióxido de Carbono , Acero , Corrosión , Acero/química , Dióxido de Carbono/química , Biopelículas , Carbono/químicaRESUMEN
In the present work, Verbena Officinalis (VO) leaf extract was used as potential corrosion inhibitor for the corrosion of carbon steel (CS) in 0.5 M H2SO4 medium. Further, the corrosion inhibiting nature of VO leaf extract towards the CS was evaluated using mass loss (ML), potentiodynamic polarization (PDP), electrical impedance spectroscopy (EIS) and surface morphological analyses using atomic force microscope (AFM) and X-ray photoelectron spectroscopy (XPS) techniques. Calculation of activation energy E a ∗ using Arrhenius equation shows the increase in activation energy when adding the VO leaf extract in 0.5 M H2SO4 medium and the maximum activation energy ( E a ∗ = 49.9 kJ mol-1) was observed for 1000 mg L-1 VO leaf extract in acid medium. The negative free energy values suggested the spontaneous and the stability of the adsorbed layer of VO leaf extract on the CS surface. Using EIS measurements, high percent inhibitory effectiveness of 91.1% for 1000 ppm solutions was achieved. With an increase in VO leaf extract dose, the double layer capacitance (Cdl) values fall while the values of charge transfer (Rct) increase. This showed that a protective layer of VO leaf extract on CS surface was formed. The polarization curves showed that the VO leaf extract acts as a mixed-type inhibitor. It is discovered that the adsorption of VO leaf extract molecules adhering to the CS surface followed the Langmuir isotherm. The anti-corrosion action of VO leaf extract is fully demonstrated by some surface techniques.
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Extractos Vegetales , Hojas de la Planta , Acero , Verbena , Extractos Vegetales/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Acero/química , Corrosión , Verbena/química , Microscopía de Fuerza Atómica , Espectroscopía de Fotoelectrones , Carbono/química , Concentración de Iones de Hidrógeno , Propiedades de Superficie , Espectroscopía DieléctricaRESUMEN
Anaerobic digestion for flexible biogas production can lead to digestion inhibition under high shock loads. While steel slag addition has shown promise in enhancing system buffering, its limitations necessitate innovation. This study synthesized the nitrogen-doped activated carbon composite from steel slag to mitigate intermediate product accumulation during flexible biogas production. Material characterization preceded experiments introducing the composite into anaerobic digestion systems, evaluating its impact on methane production efficiency under hydraulic and concentration sudden shocks. Mechanistic insights were derived from microbial community and metagenomic analyses, facilitating the construction of the modified Anaerobic Digestion Model No. 1 (ADM1) to quantitatively assess the material's effects. Results indicate superior resistance to concentration shocks with substantial increment of methane production rate up to 33.45% compared with control group, which is mediated by direct interspecies electron transfer, though diminishing with increasing shock intensity. This study contributes theoretical foundations for stable flexible biogas production and offers an effective predictive tool for conductor material reinforcement processes.
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Biocombustibles , Metano , Nitrógeno , Acero , Acero/química , Nitrógeno/química , Metano/química , Anaerobiosis , Carbón Orgánico/química , Carbono/químicaRESUMEN
Sensor array methods have received much attention in recent years. In this study, a colorimetric sensor array consisting of three kinds of steel slag-based composites (including porphyrin-functionalized non-magnetic steel slag (NMSS-Por), alkali-excited steel slag (A-SS), and platinum modified steel slag (ALANH-Pt)) was developed for the detection and recognition of tetracycline antibiotics (TCs) such as tetracycline (TC), oxytetracycline (OTC) and doxycycline (DOX). Linear discriminant analysis (LDA) and hierarchical cluster analysis (HCA) showed that the colorimetric sensor array has excellent recognition ability for TCs. The detection limits of this sensor array for TC, OTC, and DOX were 0.059 µM, 0.111 µM and 0.118 µM, respectively, which provided higher sensitivity compared to the colorimetric sensors composed of a single steel slag-based composite material. At the same time, the array sensor has anti-interference ability, and this study provides a new application route for steel slag.
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Antibacterianos , Colorimetría , Acero , Colorimetría/métodos , Colorimetría/instrumentación , Acero/química , Antibacterianos/análisis , Límite de Detección , Tetraciclina/análisis , Tetraciclina/química , Tetraciclinas/análisis , Doxiciclina/análisis , Doxiciclina/química , Análisis DiscriminanteRESUMEN
Desiccation-induced cracks in a compacted clay liner significantly deteriorate the hydraulic barrier performance of landfill covers. The present study explores the effects of polypropylene (PP) fiber reinforcement on the hydrological response and crack resistance of compacted steel slag (SS; 90 wt%) - bentonite (10 wt%) mixtures under drying and wetting cycles. Comprehensive tests were conducted to explore the impact of different fiber lengths (6-12 mm) and contents (0-0.4 % wt.%), including hydraulic conductivity tests for measuring the saturated hydraulic conductivity (ks), unconfined-penetration tests for measuring the tensile strength, small-sized plate tests for quantifying crack development, and large-sized bucket tests for studying the hydrological response and crack characteristics. Higher fiber contents and longer fiber lengths increased the ks-value of the specimens. For a 0.3 % fiber content, the tensile strength peaked for the 9-mm fiber. Consistently, the specimen reinforced with the 9-mm fibers exhibited significantly fewer cracks than those reinforced with the 6-mm and 12-mm fibers. It was because the 6-mm fibers had a shorter anchorage length, while the 12-mm fibers tended to agglomerate. The large-sized bucket tests showed that fiber reinforcement limited crack development significantly under wetting and drying cycles, reducing the rainfall infiltration by 40 % and enhancing the soil water retention capacity. Finally, a 0.3 wt% of 9-mm PP was recommended to reinforce the compacted SS-bentonite mixtures.
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Bentonita , Polipropilenos , Acero , Polipropilenos/química , Bentonita/química , Acero/química , Resistencia a la Tracción , Hidrología , Desecación/métodos , Eliminación de Residuos/métodosRESUMEN
This study evaluated Aloe vera extract as a green inhibitor to prevent corrosion in seawater environments. A. vera extract was produced by maceration with methanol-water at room temperature. Electrochemical techniques were used to evaluate the corrosion inhibitor effectiveness of the A. vera extract. The morphology of the corrosion products was analyzed by FE-SEM equipped with EDS and AFM. FT-IR and LCMS characterized the functional and structural groups in this extract. The electrochemical measurements show that A. vera extract could effectively reduce the corrosion of API 5L steel in seawater environments. Inhibition efficiency (IE) increases with increasing concentration. Optimal corrosion inhibition efficiency of around 83.75% (PDP) and 88.60% (EIS) was obtained by adding 300 mg L-1 of extract at 310 K. Furthermore, the higher the concentration of A. vera extract, the greater the activation energy (Ea), with the highest activation energy being 48.24 kJ mol-1 for the concentration of 300 mg L-1. Conversely, increasing the temperature and exposure duration reduces the corrosion inhibition efficiency (IE) values; the best exposure period was 30 min with 88.34% IE by a concentration of 300 mg L-1 at 300 K. This corrosion inhibition is achieved by the adsorption process of A. vera bioactive on metal surfaces with a mixed inhibitor through a physisorption-chemisorption mechanism. This finding was confirmed by the smoother surface morphology of the steel treated with A. vera extract than without. This unveiling investigation found that A. vera extract has the potential to be an environmentally friendly corrosion inhibitor in the seawater environment.
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Aloe , Extractos Vegetales , Agua de Mar , Acero , Corrosión , Agua de Mar/química , Acero/química , Aloe/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
Partially encased concrete (PEC) has better mechanical properties as a structure where steel and concrete work together. Due to the increasing amount of construction waste, recycled aggregate concrete (RAC) is being considered by more people. However, although RAC has more points, the performance is inferior to natural aggregate concrete (NAC). To narrow or address this gap, lightweight, high-strength and corrosion-resistant CFRP can be used, also protecting the steel flange of the PEC structure. Therefore, carbon fiber reinforced polymer (CFRP) confined partially encased recycled coarse aggregate concrete columns were studied in this paper. With respect to different slenderness ratios, recycled coarse aggregate(RCA) replacement ratios, and number of CFRP layers, the performance of the proposed CFRP restrained columns are reported. The RCA replacement ratio is analyzed to be limited negative impact on the bearing capacity, generally within 6%. As for the slenderness ratio, the bearing capacity increased with it. However, wrapping CFRP significantly increased the bearing capacity. Considering the arch factor, a simple formula for calculating the ultimate strength of CFRP-confined partially encased RAC columns is developed based on EC4 and GB50017-2017. By comparison with the experimental values, the error is within 10%.
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Fibra de Carbono , Fuerza Compresiva , Materiales de Construcción , Polímeros , Reciclaje , Fibra de Carbono/química , Materiales de Construcción/análisis , Polímeros/química , Ensayo de Materiales , Acero/químicaRESUMEN
The purpose of this study is to evaluate the corrosion resistance in natural seawater (Navodari area) of two types of low-alloy carbon steels BVDH36 and LRAH36 by electrochemical methods. The electrochemical methods used were the evolution of the free potential (OCP), electrochemical impedance spectroscopy (EIS), polarization resistance (Rp) and corrosion rate (Vcorr), potentiodynamic polarization (PD), and cyclic voltammetry (CV). The studies were completed by ex situ characterization analyzes of the studied surfaces before and after corrosion such as: optical microscopy, scanning electron microscopy and X-ray diffraction analysis. The results of the study show us that the polarization resistance of the low-alloy carbon steel BVDH36 is higher compared to the polarization resistance of the low-alloy carbon steel LRAH36. It is also observed that with the increase in the immersion time of the samples in natural seawater, the polarization resistance of the BVDH36 alloy increases over time and finally decreases, and for the carbon steel LRAH36 the polarization resistance increases.
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Aleaciones , Agua de Mar , Acero , Corrosión , Acero/química , Aleaciones/química , Difracción de Rayos X , Espectroscopía Dieléctrica , Técnicas Electroquímicas , Microscopía Electrónica de Rastreo , Carbono/químicaRESUMEN
Ladle slag, a by-product of steelmaking, presents a valuable strategy for waste reduction and valorization in wastewater treatment. This work demonstrates the successful simultaneous removal of Al(III), B(III), Ba(II), Cr(III), Mg(II), Sr(II), Pb(II), and Zn(II), from electroplating wastewater by ladle slag. First, Cr(III) and Pb(II) removals were evaluated in single synthetic systems by analyzing the influence of pH, temperature, and ladle slag dosage. Competitive removal was observed in binary batch experiments of Cr(III) - Pb(II), achieving 88% and 96% removal, respectively, with fast kinetics following a pseudo-second-order model. The findings of XRD, SEM, EDX, and FTIR of the slag after removal helped to elucidate the synergic removal mechanism involving ladle slag dissolution, precipitation, ion exchange, and adsorption in a tight relationship with the solution pH. Lastly, ladle slag was tested in real electroplating wastewater with the aforementioned ions at concentrations ranging from <1 to 1700 mg/L. The removal was performed in two steps, the first attained the following efficiencies: 73% for Al(III), 88% for B(III), 98% for Ba(II), 80% for Cr(III), 82% for Mg(II), 99% for Pb(II), 88% for Sr(II), and 88% for Zn(II). Visual MINTEQ simulation was utilized to identify the different species of ions present during the removal process. Furthermore, the leaching tests indicated a minimal environmental risk of secondary pollution in its application. The results promote an effective and sustainable approach to wastewater treatment within the circular economy.
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Galvanoplastia , Metales Pesados , Eliminación de Residuos Líquidos , Aguas Residuales , Contaminantes Químicos del Agua , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/química , Metales Pesados/aislamiento & purificación , Metales Pesados/análisis , Metales Pesados/química , Eliminación de Residuos Líquidos/métodos , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Residuos Industriales/análisis , Acero/químicaRESUMEN
INTRODUCTION: Metallic and elastomeric ligatures are widely used in orthodontics to secure the archwire within the bracket slots, but elastomeric ligatures have traditionally been associated with increased microbial colonization, which could adversely affect periodontal health. AIM: This systematic review compares the periodontal effects of elastomeric and steel ligatures used for orthodontic fixed appliances. METHODS: Unrestricted literature search of 7 databases (MEDLINE, Scopus, Web of Science, Embase, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, and Virtual Health Library) up to July 2023 were performed for randomized / non-randomized clinical studies on humans comparing the two ligation methods during fixed-appliance therapy. After duplicate study selection, data extraction, and risk-of-bias assessment with the Risk of Bias (RoB) 2 or the Risk Of Bias In Non-randomized Studies - of Interventions (ROBINS-I) tool, random-effects meta-analyses of Mean Differences (MD) or Standardized Mean Differences (SMD) and their 95% confidence intervals (CIs) were carried out, followed by assessment of certainty of existing evidence with the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) approach. RESULTS: A total of 11 studies (3 randomized / 8 non-randomized) with 354 patients (mean age 14.7 years and 42% male) were included. No statistically significant differences were seen for plaque index (5 studies; SMD = 0.48; 95% CI = -0.03 to 1.00; P = 0.07), gingival index (2 studies; MD = 0.01; 95% CI = -0.14 to 0.16; P = 0.89), probing pocket depth (2 studies; MD = 0; 95% CI = -0.17 to 0.16; P = 0.97), or Streptococcus mutans counts (4 studies; SMD = 0.40; 95% CI=-0.41 to 1.20; P = 0.21). Elastomeric ligatures were associated with moderately increased total bacterial load (3 studies; SMD = 0.43; 95% CI = 0.10 to 0.76; P = 0.03). Confidence in these estimates was low in all instances due to the inclusion of non-randomized studies with high risk of bias. CONCLUSIONS: Existing low quality evidence indicates that ligature method does not seem to influence the periodontal health during fixed treatment, even if elastomeric ligatures are associated with a moderate increase of bacterial load. REGISTRATION: PROSPERO (CRD42023444383).
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Elastómeros , Aparatos Ortodóncicos Fijos , Humanos , Acero , Índice Periodontal , Soportes Ortodóncicos , LigaduraRESUMEN
The present study focuses on an environmental approach based on the use of an eco-friendly corrosion inhibitor from the Citrullus colocynthis fruit extract for enhancement corrosion resistance of carbon steel (C-S) in acid medium as an alternative to various organic and non-organic chemical inhibitors. The evaluation of the inhibition properties of the fruit methanolic extract of Citrullus colocynthis (CCE) were performed in molar hydrochloric acid (1 M HCl) medium using gravimetric and electrochemical (potentiodynamic polarization and AC impedance) techniques as well as surface analyses. CCE is rich in amino acids, mainly citrulline and ß-(pyrazo-1-yl)-L-analine molecules. Based on the weight loss evaluation, the results demonstrated that this plant extract acts as an effective corrosion inhibitor and a protection level of 93.6% was attained at 500 ppm of CCE after 6 h of metal exposure at 303 K. According to polarization curves, CCE functions as a mixed-type inhibitor. In addition, AC impedance analyses have shown that the incorporation of CCE into the corrosive solution leads to a decrease in load capacity, while improving the charge/discharge function at the interface. This suggests the possibility of the formation of an adsorbed layer on the C-S surface. In addition, scanning electron microscope (SEM) observation, contact angle measurements, and Fourier-transform infrared spectroscopy (FTIR) analyses supported the development of a protective film over CS substrate surface afterwards addition of CCE. Langmuir and/or Temkin isotherms can be used to characterize the adsorption of this organic inhibitor on the C-S surface. X-ray photoelectron spectroscopy (XPS) has revealed that the inhibiting effect of CCE on the corrosion of C-S in 1 M HCl solution is mainly controlled by a chemisorption process and the inhibitive layer is composed of an iron oxide/hydroxide mixture where CCE molecules are incorporated. In order to understand the relationship between the molecular structure and anti-corrosion effectiveness of these inhibitor molecules, quantum chemical studies were carried out using density functional theory (DFT) and molecular dynamics (MD) simulation.
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Citrullus colocynthis , Frutas , Ácido Clorhídrico , Extractos Vegetales , Acero , Corrosión , Acero/química , Ácido Clorhídrico/química , Frutas/química , Extractos Vegetales/química , Citrullus colocynthis/química , Carbono/químicaRESUMEN
The iron and steel-making industries have garnered significant attention in research related to low-carbon transitions and the reuse of steel slag. This industry is known for its high carbon emissions and the substantial amount of steel slag it generates. To address these challenges, a waste heat recovery process route has been developed for molten steel slag, which integrates CO2 capture and fixation as well as efficient utilization of steel slag. This process involves the use of lime kiln flue gas from the steel plant as the gas quenching agent, thereby mitigating carbon emissions and facilitating carbonation conversion of steel slag while simultaneously recovering waste heat. The established carbonation model of steel slag reveals that the insufficient diffusion of CO2 gas molecules within the product layer is the underlying mechanism hindering the carbonation performance of steel slag. This finding forms the basis for enhancing the carbonation performance of steel slag. The results of Aspen Plus simulation indicate that 1 t of steel slag (with a carbonation conversion rate of 15.169 %) can fix 55.19 kg of CO2, process 6.08 kmol of flue gas (with a carbon capture rate of 92.733 %), and recover 2.04 GJ of heat, 0.43 GJ of exergy, and 0.68 MWh of operating cost. These findings contribute to the development of sustainable and efficient solutions for steel slag management, with potential applications in the steel production industry and other relevant fields.
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Calor , Residuos Industriales , Acero , Acero/química , Residuos Industriales/análisis , Dióxido de Carbono/análisis , Dióxido de Carbono/química , Carbono/química , Administración de Residuos/métodos , Metalurgia/métodos , Óxidos/química , Reciclaje/métodos , GasesRESUMEN
Iron and steel slags have a long history of both disposal and beneficial use in the coastal zone. Despite the large volumes of slag deposited, comprehensive assessments of potential risks associated with metal(loid) leaching from iron and steel by-products are rare for coastal systems. This study provides a national-scale overview of the 14 known slag deposits in the coastal environment of Great Britain (those within 100 m of the mean high-water mark), comprising geochemical characterisation and leaching test data (using both low and high ionic strength waters) to assess potential leaching risks. The seaward facing length of slag deposits totalled at least 76 km, and are predominantly composed of blast furnace (iron-making) slags from the early to mid-20th Century. Some of these form tidal barriers and formal coastal defence structures, but larger deposits are associated with historical coastal disposal in many former areas of iron and steel production, notably the Cumbrian coast of England. Slag deposits are dominated by melilite phases (e.g. gehlenite), with evidence of secondary mineral formation (e.g. gypsum, calcite) indicative of weathering. Leaching tests typically show lower element (e.g. Ba, V, Cr, Fe) release under seawater leaching scenarios compared to deionised water, largely ascribable to the pH buffering provided by the former. Only Mn and Mo showed elevated leaching concentrations in seawater treatments, though at modest levels (<3 mg/L and 0.01 mg/L, respectively). No significant leaching of potentially ecotoxic elements such as Cr and V (mean leachate concentrations <0.006 mg/L for both) were apparent in seawater, which micro-X-Ray Absorption Near Edge Structure (µXANES) analysis show are both present in slags in low valence (and low toxicity) forms. Although there may be physical hazards posed by extensive erosion of deposits in high-energy coastlines, the data suggest seawater leaching of coastal iron and steel slags in the UK is likely to pose minimal environmental risk.
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Monitoreo del Ambiente , Hierro , Acero , Hierro/química , Hierro/análisis , Contaminantes Químicos del Agua/análisis , Agua de Mar/químicaRESUMEN
Steel slag (SS) is a byproduct that comes from the production of crude steel in alkaline oxidation furnaces. Resource utilization of steel slag, a calcium-silicon solid waste, is an urgent problem. This paper investigates a solid waste disposal method that applies different steel slag contents to modify dispersive soil. The engineering properties and modification mechanisms of dispersive soil specimens are studied and revealed by performing microstructure, mineral evolution, unconfined compressive strength (UCS), and tensile strength analysis. The pinhole test, mud ball crumb test (BCT), and mud cube crumb test (CCT) were carried out to determine the dispersivity of the soil specimens. Results show that when the steel slag content increases from 1% to 10%, the unconfined compressive strength and tensile strength increase by 176.05% and 75.40%, respectively. For soil specimens without curing time under 50 mm water head, the weight loss of the specimen with 10% steel slag content decreases by 72.03% compared to specimens with 1% steel slag content. Microstructural and mineralogical analyses indicate that the hydration reaction of steel slag changes the ionic composition of the soil and generates reaction products with effects such as filling and connection. To sum up, steel slag effectively improves water stability and mechanical properties of dispersive soil.
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Compuestos de Calcio , Silicatos , Suelo , Acero , Suelo/química , Silicatos/química , Compuestos de Calcio/química , Resistencia a la Tracción , Fuerza CompresivaRESUMEN
The steel industry, crucial to the global economy, grapples with critical sustainable challenges, including high energy consumption, greenhouse gas emissions, and non-renewable resource utilization, making sustainability imperative for upholding its economic role without compromising the planet or societal well-being. This study proposes a framework aimed at advancing sustainability in the steel industry through the articulation of the triple helix sectors (university, industry, and government). Based on the integrative review scientific method, systematic selection, interpretation, and synthesis of information from various sources were carried out to map a technical-scientific scenario of sustainability in the steel industry. This scenario informed benchmarking which, in light of the scientific theory and the authors' expertise, enabled the proposition of customized actions aimed at the triple helix actors. The main theoretical-scientific contribution lies in deepening and expanding the knowledge that connects sustainability to the steel industry, thus reinforcing the basis for future research and empirical studies. As for the managerial-applied contribution, this work can guide universities in developing sustainable projects and establishing industrial partnerships; steel companies benefit from the best practices and technologies, while also achieving regulatory compliance; and governments can promote public policies that boost sustainability in the steel sector.
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Acero , Industrias , MetalurgiaRESUMEN
Steel cord materials were found to have internal porous microstructures and complex fluid flow properties. However, current studies have rarely reported the transport behavior of steel cord materials from a microscopic viewpoint. The computed tomography (CT) scanning technology and lattice Boltzmann method (LBM) were used in this study to reconstruct and compare the real three-dimensional (3D) pore structures and fluid flow in the original and tensile (by loading 800 N force) steel cord samples. The pore-scale LBM results showed that fluid velocities increased as displacement differential pressure increased in both the original and tensile steel cord samples, but with two different critical values of 3.3273 Pa and 2.6122 Pa, respectively. The original steel cord sample had higher maximal and average seepage velocities at the 1/2 sections of 3D construction images than the tensile steel cord sample. These phenomena should be attributed to the fact that when the original steel cord sample was stretched, its porosity decreased, pore radius increased, flow channel connectivity improved, and thus flow velocity increased. Moreover, when the internal porosity of tensile steel cord sample was increased by 1 time, lead the maximum velocity to increase by 1.52 times, and the average velocity was increased by 1.66 times. Furthermore, when the density range was determined to be 0-38, the pore phase showed the best consistency with the segmentation area. Depending on the Zou-He Boundary and Regularized Boundary, the relative error of simulated average velocities was only 0.2602 percent.
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Acero , Acero/química , Porosidad , Resistencia a la Tracción , Hidrodinámica , Tomografía Computarizada por Rayos XRESUMEN
Lifting-correction is a technique to restore buildings experiencing uneven settlement, while ensuring the safety and integrity of the main structural system. This study was based on a real light-steel building structure and provided a detailed description of scenarios involving uneven settlement and the process of lifting and correction. Additionally, a sophisticated finite element (FE) model was established using the generic FE software ABAQUS, with refined material constitutive models to ensure the accuracy of simulation results. Firstly, the impact of uneven settlement on the structure was examined, including modal and stress field analyses. Different methods of breaking column (BC) and lifting column (LC) were compared and scrutinized to identify optimal approaches and minimize damage and disturbance to the building. Four methods have been proposed and compared, including simultaneously breaking columns, breaking columns with chessboard style, simultaneously lifting columns and lifting columns in multiple stages. The four methods were comprehensively evaluated from the perspectives of stress fields, displacement responses, damage and energy dissipation. The results indicated that after uneven settlement, the eigenvalues and frequencies of the structure decrease, the structure tended to be unstable. Simultaneously, as stress increases, some joints' materials enter the yielding stage, affecting the overall structural stability and safety. When damage occurs in some joints, the structural safety was compromised. The comparison between the two BC methods, including the chessboard style and simultaneously BC methods, it was revealed that the former causes less disturbance to structural initial stress field. The comparison between the two LC methods, including, simultaneously and LC in multiple stages, it was revealed that the latter performs slightly better in terms of stress fields, displacement fields, damage, energy dissipation and internal forces. Therefore, the methods of BC in chessboard style and LC in multiple stages were recommended to use in engineering practice to ensure less structural disturbance. The findings obtained from this study can provide guidance for structural engineers to solve the uneven settlement of buildings.