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Sarabadani Tafreshi S, Ranjbar M, Taghizade N, Panahi SFKS, Jamaati M, de Leeuw NH. A first-principles study of CO2 hydrogenation on Niobium-terminated NbC (111) surface. Chemphyschem 2022; 23:e202100781. [PMID: 35040247 DOI: 10.1002/cphc.202100781] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 01/15/2022] [Indexed: 11/06/2022]
Abstract
As a promising material for the reduction of Greenhouse gas, Transition metal carbides which are highly active in the hydrogenation of CO2 are mainly considered. In this regard, the reaction mechanism of CO2 hydrogenation to useful products on the Nb-terminated NbC (111) surface is investigated by applying density functional theory calculations. The computational results display that formation of CH4 , CH3OH and CO are more favored than other compounds, where CH4 is the dominant product. In addition, the findings from reaction energies reveal that the preferred mechanism for CO2 hydrogenation is thorough HCOOH * where the largest exothermic reaction energy releases during HCOOH * dissociation reaction (2.004eV). The preferred mechanism of CO2 hydrogenation towards CH 4 production is CO2 *→ t,c-COOH *→ HCOOH *→ HCO *→ CH2O *→ CH2OH *→ CH2 *→ CH3 *→ CH4 * where CO2 * → t,c-COOH * → HCOOH * → HCO * → CH2O * → CH2OH * → CH3OH * and CO2 * → t,c-COOH * → CO * are also found as the favored mechanisms for CH3 OH and CO productions thermodynamically, respectively. During the mentioned mechanisms the hydrogenation of CH2O * to CH2OH * has the largest endothermic reaction energy of 1.344 eV. It is also found from the electronic properties calculations that Nb-terminated NbC (111) is a suitable catalyst for CO2 hydrogenation where adsorption and activation of CO2 and also desorption of final products can be easily done on the surface.
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Affiliation(s)
| | - Mahkameh Ranjbar
- Amirkabir University of Technology, chemistry, IRAN (ISLAMIC REPUBLIC OF)
| | - Narges Taghizade
- Iran University of Science and Technology School of Physics, physics, IRAN (ISLAMIC REPUBLIC OF)
| | - S F K S Panahi
- Iran University of Science and Technology School of Physics, physics, IRAN (ISLAMIC REPUBLIC OF)
| | - Maryam Jamaati
- Iran University of Science and Technology School of Physics, physics, IRAN (ISLAMIC REPUBLIC OF)
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Kobayashi Y, Takahashi J, Kawakami K, Hono K. Determination of the Chemical Compositions of Fine titanium Carbide and Niobium Carbide Precipitates in Isothermally Aged Ferritic Steel by Atom Probe Tomography Analysis. Microsc Microanal 2021; 27:1-11. [PMID: 33280630 DOI: 10.1017/s143192762002471x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The carbon (C) ratios, namely the atomic ratios of C/(C + M), in nano-sized coherent MC precipitates (M = Ti, Nb) with the NaCl-type (B1) structure in ferritic steels, which had been isothermally aged at 580 °C, were investigated using atom probe tomography (APT). Considering the influences of the trajectory aberration, detection loss, and peak overlap, we determined the C ratios to be ~0.40 and ~0.45 for an equivalent volume diameter of 1.5–5 nm and 1–5 nm for the TiC and NbC precipitates, respectively, suggesting that there is a considerable fraction of C vacancies in both nano-sized precipitates. The apparent C ratios show significant scatter with decreasing particle size, while the apparent mean C ratios of very fine TiC particles, smaller than 1.5 nm, decreased with decreasing particle size. With the use of one of the latest APT instruments with a high detection efficiency, the scattering in the apparent C ratios was reduced because the counting statistics were improved; however, the artificial enrichment of C atoms to particular crystallographic directions of ferrite hindered the determination of the C ratio for very fine TiC particles smaller than 1.5 nm.
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Affiliation(s)
- Yukiko Kobayashi
- Advanced Technology Research Labs., Nippon Steel Corporation, 20-1 Shintomi, Futtsu, Chiba293-8511, Japan
- Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba305-8577, Japan
| | - Jun Takahashi
- Advanced Technology Research Labs., Nippon Steel Corporation, 20-1 Shintomi, Futtsu, Chiba293-8511, Japan
| | - Kazuto Kawakami
- Nippon Steel Technology Co., Ltd., 20-1 Shintomi, Futtsu, Chiba293-0011, Japan
| | - Kazuhiro Hono
- Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba305-8577, Japan
- National Institute for Materials Science, 1-2-1 Sengen, Tsukuba305-0047, Japan
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Shi B, Huang S, Zhu P, Xu C, Zhang T. Microstructure and Wear Behavior of In-Situ NbC Reinforced Composite Coatings. Materials (Basel) 2020; 13:E3459. [PMID: 32764507 PMCID: PMC7475928 DOI: 10.3390/ma13163459] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 08/02/2020] [Accepted: 08/04/2020] [Indexed: 11/17/2022]
Abstract
In the present study, plasma spray welding was used to prepare an in-situ niobium carbide (NbC) reinforced Ni-based composite coating on the low carbon steel, and the phase composition and the microstructure of the composite coatings were studied. The wear resistance and the wear mechanism of the composite coatings were also researched by the wear tests. The results showed that the main phases of the composite coating were NbC, γ-Ni, Cr23C6, Ni3Si, CrB, Cr5B3, Cr7C3 and FeNi3. A number of fine in-situ NbC particles and numerous chromium carbide particles were distributed in the γ-Ni matrix. The increase in the mass fraction of Nb and NiCr-Cr3C2 could lead to the increase in NbC particles in the composite coatings. Due to the high hardness of NbC and chromium carbides, the micro-hardness and the wear resistance of the composite coatings were advanced. The composite coating with the powder mixtures of 20% (Nb + NiCr-Cr3C2) and 80% NiCrBSi had the highest micro-hardness and the best wear resistance in this study. The average micro-hardness reached the maximum value 1025HV0.5. The volume loss was 39.2 mm3, which was merely 37% of that of the NiCrBSi coating and 6% of that of the substrate under the identical conditions.
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Affiliation(s)
| | - Shiming Huang
- School of Materials Science and Engineering, Dalian Jiaotong University, Dalian 116028, China; (B.S.); (P.Z.); (C.X.); (T.Z.)
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Królicka A, Szczepański Ł, Konat Ł, Stawicki T, Kostencki P. The Influence of Microstructure on Abrasive Wear Micro-Mechanisms of the Claddings Produced by Welding Used in Agricultural Soil. Materials (Basel) 2020; 13:ma13081920. [PMID: 32325859 PMCID: PMC7215780 DOI: 10.3390/ma13081920] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 04/14/2020] [Accepted: 04/16/2020] [Indexed: 11/16/2022]
Abstract
Claddings produced by welding are commonly used to increase the durability of the working elements of agricultural tools. The working conditions that occur during the cultivation of agricultural soil determine the wear intensity (different soil fractions, biological, and chemical environment). It was found that the tested claddings (Fe-Cr-C-Nb system) is characterized by three different layers: hypereutectic (layer I), near eutectic (layer II), and hypoeutectic (layer III). In layer I, micro-cracking and spalling of hard and brittle primary M7C3 carbides resulted in micro-delamination under the impact of larger soil fractions, which increased the wear intensity. Due to the lower fraction of primary M7C3 carbides in layer II, the share of micro-delamination was less significant in comparison to layer I. It was found that niobium carbides are firmly embedded in the matrix and effectively inhibit wear intensity in layer I and layer II. Layer III contained austenite dendrites, a refined eutectic mixture, and also NbC. In this layer, cracks (caused the unfavorable eutectic mixture morphology) were found in the interdendritic spaces at the worn surface. After the penetration of the cladding, there was a "wash-out effect", which resulted in a significant reduction in the durability of the working elements due to abrasive wear.
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Affiliation(s)
- Aleksandra Królicka
- Faculty of Mechanical Engineering, Wroclaw University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wroclaw, Poland; (Ł.S.); (Ł.K.)
- Correspondence:
| | - Łukasz Szczepański
- Faculty of Mechanical Engineering, Wroclaw University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wroclaw, Poland; (Ł.S.); (Ł.K.)
| | - Łukasz Konat
- Faculty of Mechanical Engineering, Wroclaw University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wroclaw, Poland; (Ł.S.); (Ł.K.)
| | - Tomasz Stawicki
- Department of Engineering of Renewable Energy Sources, Faculty of Environmental Management and Agriculture, West Pomeranian University of Technology in Szczecin, Papieza Pawla VI Street 1, 71-459 Szczecin, Poland; (T.S.); (P.K.)
| | - Piotr Kostencki
- Department of Engineering of Renewable Energy Sources, Faculty of Environmental Management and Agriculture, West Pomeranian University of Technology in Szczecin, Papieza Pawla VI Street 1, 71-459 Szczecin, Poland; (T.S.); (P.K.)
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Ren X, Huo M, Wang M, Lin H, Zhang X, Yin J, Chen Y, Chen H. Highly Catalytic Niobium Carbide (MXene) Promotes Hematopoietic Recovery after Radiation by Free Radical Scavenging. ACS Nano 2019; 13:6438-6454. [PMID: 31180624 DOI: 10.1021/acsnano.8b09327] [Citation(s) in RCA: 103] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Ionizing radiation (IR) has been extensively used in industry and radiotherapy, but IR exposure from nuclear or radiological accidents often causes serious health effects in an exposed individual, and its application in radiotherapy inevitably brings undesirable damage to normal tissues. In this work, we have developed ultrathin two-dimensional (2D) niobium carbide (Nb2C) MXene as a radioprotectant and explored its application in scavenging free radicals against IR. The 2D Nb2C MXene features intriguing antioxidant properties in effectively eliminating hydrogen peroxide (H2O2), hydroxyl radicals (•OH), and superoxide radicals (O2•-). Pretreatment with biocompatible polyvinylpyrrolidone (PVP)-functionalized Nb2C nanosheets (Nb2C-PVP NSs) significantly reduces IR-induced production of reactive oxygen species (ROS), resulting in enhanced cell viability in vitro. A single intravenous injection of Nb2C-PVP significantly enhances the survival rate of 5 and 6.5 Gy irradiated mice to 100% and 81.25%, respectively, and significantly increases bone marrow mononuclear cells after IR. Critically, Nb2C-PVP reverses the damage of the hematopoietic system in irradiated mice. Single administration of Nb2C-PVP significantly increases superoxide dismutase (SOD) activities, decreases malondialdehyde levels, and thereby reduces IR-induced pathological damage in the testis, small intestine, lung, and liver of 5 Gy irradiated mice. Importantly, Nb2C-PVP is almost completely eliminated from the mouse body on day 14 post treatment, and no obvious toxicities are observed during the 30-day post treatment period. Our study pioneers the application of 2D MXenes with intrinsic radioprotective nature in vivo.
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Affiliation(s)
- Xiangyi Ren
- Department of Radiation Biology, Institute of Radiation Medicine , Fudan University , Shanghai , 200032 , People's Republic of China
| | - Minfeng Huo
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure , Shanghai Institute of Ceramics, Chinese Academy of Sciences , Shanghai , 200050 , People's Republic of China
- University of Chinese Academy of Science , Beijing , 100049 , People's Republic of China
| | - Mengmeng Wang
- Department of Radiation Biology, Institute of Radiation Medicine , Fudan University , Shanghai , 200032 , People's Republic of China
| | - Han Lin
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure , Shanghai Institute of Ceramics, Chinese Academy of Sciences , Shanghai , 200050 , People's Republic of China
- University of Chinese Academy of Science , Beijing , 100049 , People's Republic of China
| | - Xuxia Zhang
- Department of Radiation Biology, Institute of Radiation Medicine , Fudan University , Shanghai , 200032 , People's Republic of China
| | - Jun Yin
- Department of Radiation Biology, Institute of Radiation Medicine , Fudan University , Shanghai , 200032 , People's Republic of China
| | - Yu Chen
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure , Shanghai Institute of Ceramics, Chinese Academy of Sciences , Shanghai , 200050 , People's Republic of China
| | - Honghong Chen
- Department of Radiation Biology, Institute of Radiation Medicine , Fudan University , Shanghai , 200032 , People's Republic of China
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Cofiño-Villar A, Alvarez-Antolin F, Asensio-Lozano J. Enhancement of the Quality of the Shell-Core Bond Interface in Duplex Work Rolls Manufactured by Centrifugal Casting Used in Hot Strip Mills. Materials (Basel) 2019; 12:ma12081304. [PMID: 31010045 PMCID: PMC6514822 DOI: 10.3390/ma12081304] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 04/16/2019] [Accepted: 04/18/2019] [Indexed: 11/16/2022]
Abstract
To ensure the formation of a sound shell-core bond interface free of defects between the shell and the core in work rolls used in the finishing stands of hot strip mills, a complete fusion of this interface must be achieved, avoiding excessive mixing of the two components and the formation of hard, fragile microstructures. The shell is made of white cast iron, alloyed with Ni and Cr, and the core is manufactured of grey cast iron spheroidal graphite in a pearlitic matrix. It is thus advisable to inoculate the shell with 0.6 kg/T SiCaMn, as this promotes discontinuity in the carbide network and leads to an increase in the impact toughness of the bond interface. Furthermore, inoculation of the shell with FeSi-La should be avoided, as this inoculant leads to an increase in graphite counts, promoting it with a lamellar morphology at the edge of the bond and hence reducing the impact toughness in this interface. Addition of Mg to the shell has been found to produce an increase in hardness in the regions adjacent to the bond interface.
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Affiliation(s)
- Alberto Cofiño-Villar
- Materials Pro Group, Departamento de Ciencia de los Materiales e IngenieríaMetalúrgica, Universidad de Oviedo; Independencia 13, 33004 Oviedo, Spain.
| | - Florentino Alvarez-Antolin
- Materials Pro Group, Departamento de Ciencia de los Materiales e IngenieríaMetalúrgica, Universidad de Oviedo; Independencia 13, 33004 Oviedo, Spain.
| | - Juan Asensio-Lozano
- Materials Pro Group, Departamento de Ciencia de los Materiales e IngenieríaMetalúrgica, Universidad de Oviedo; Independencia 13, 33004 Oviedo, Spain.
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